QEMU-QMP-REF(7) QEMU QEMU-QMP-REF(7)
NAME
qemu-qmp-ref - QEMU QMP Reference Manual
Contents
• QEMU QMP Reference Manual
• Introduction
• This document describes all commands currently supported by QMP.
• Stability Considerations
• The current QMP command set (described in this file) may be use-
ful for a number of use cases, however it's limited and several
commands have bad defined semantics, specially with regard to
command completion.
• QMP errors
• QapiErrorClass (Enum)
• Common data types
• IoOperationType (Enum)
• OnOffAuto (Enum)
• OnOffSplit (Enum)
• String (Object)
• StrOrNull (Alternate)
• OffAutoPCIBAR (Enum)
• PCIELinkSpeed (Enum)
• PCIELinkWidth (Enum)
• HostMemPolicy (Enum)
• NetFilterDirection (Enum)
• GrabToggleKeys (Enum)
• HumanReadableText (Object)
• Socket data types
• NetworkAddressFamily (Enum)
• InetSocketAddressBase (Object)
• InetSocketAddress (Object)
• UnixSocketAddress (Object)
• VsockSocketAddress (Object)
• InetSocketAddressWrapper (Object)
• UnixSocketAddressWrapper (Object)
• VsockSocketAddressWrapper (Object)
• StringWrapper (Object)
• SocketAddressLegacy (Object)
• SocketAddressType (Enum)
• SocketAddress (Object)
• VM run state
• RunState (Enum)
• ShutdownCause (Enum)
• StatusInfo (Object)
• query-status (Command)
• SHUTDOWN (Event)
• POWERDOWN (Event)
• RESET (Event)
• STOP (Event)
• RESUME (Event)
• SUSPEND (Event)
• SUSPEND_DISK (Event)
• WAKEUP (Event)
• WATCHDOG (Event)
• WatchdogAction (Enum)
• RebootAction (Enum)
• ShutdownAction (Enum)
• PanicAction (Enum)
• watchdog-set-action (Command)
• set-action (Command)
• GUEST_PANICKED (Event)
• GUEST_CRASHLOADED (Event)
• GuestPanicAction (Enum)
• GuestPanicInformationType (Enum)
• GuestPanicInformation (Object)
• GuestPanicInformationHyperV (Object)
• S390CrashReason (Enum)
• GuestPanicInformationS390 (Object)
• MEMORY_FAILURE (Event)
• MemoryFailureRecipient (Enum)
• MemoryFailureAction (Enum)
• MemoryFailureFlags (Object)
• NotifyVmexitOption (Enum)
• Cryptography
• QCryptoTLSCredsEndpoint (Enum)
• QCryptoSecretFormat (Enum)
• QCryptoHashAlgorithm (Enum)
• QCryptoCipherAlgorithm (Enum)
• QCryptoCipherMode (Enum)
• QCryptoIVGenAlgorithm (Enum)
• QCryptoBlockFormat (Enum)
• QCryptoBlockOptionsBase (Object)
• QCryptoBlockOptionsQCow (Object)
• QCryptoBlockOptionsLUKS (Object)
• QCryptoBlockCreateOptionsLUKS (Object)
• QCryptoBlockOpenOptions (Object)
• QCryptoBlockCreateOptions (Object)
• QCryptoBlockInfoBase (Object)
• QCryptoBlockInfoLUKSSlot (Object)
• QCryptoBlockInfoLUKS (Object)
• QCryptoBlockInfo (Object)
• QCryptoBlockLUKSKeyslotState (Enum)
• QCryptoBlockAmendOptionsLUKS (Object)
• QCryptoBlockAmendOptions (Object)
• SecretCommonProperties (Object)
• SecretProperties (Object)
• SecretKeyringProperties (Object)
• TlsCredsProperties (Object)
• TlsCredsAnonProperties (Object)
• TlsCredsPskProperties (Object)
• TlsCredsX509Properties (Object)
• QCryptoAkCipherAlgorithm (Enum)
• QCryptoAkCipherKeyType (Enum)
• QCryptoRSAPaddingAlgorithm (Enum)
• QCryptoAkCipherOptionsRSA (Object)
• QCryptoAkCipherOptions (Object)
• Block devices
• Block core (VM unrelated)
• Background jobs
• Additional block stuff (VM related)
• Block device exports
• Character devices
• ChardevInfo (Object)
• query-chardev (Command)
• ChardevBackendInfo (Object)
• query-chardev-backends (Command)
• DataFormat (Enum)
• ringbuf-write (Command)
• ringbuf-read (Command)
• ChardevCommon (Object)
• ChardevFile (Object)
• ChardevHostdev (Object)
• ChardevSocket (Object)
• ChardevUdp (Object)
• ChardevMux (Object)
• ChardevStdio (Object)
• ChardevSpiceChannel (Object)
• ChardevSpicePort (Object)
• ChardevDBus (Object)
• ChardevVC (Object)
• ChardevRingbuf (Object)
• ChardevQemuVDAgent (Object)
• ChardevBackendKind (Enum)
• ChardevFileWrapper (Object)
• ChardevHostdevWrapper (Object)
• ChardevSocketWrapper (Object)
• ChardevUdpWrapper (Object)
• ChardevCommonWrapper (Object)
• ChardevMuxWrapper (Object)
• ChardevStdioWrapper (Object)
• ChardevSpiceChannelWrapper (Object)
• ChardevSpicePortWrapper (Object)
• ChardevQemuVDAgentWrapper (Object)
• ChardevDBusWrapper (Object)
• ChardevVCWrapper (Object)
• ChardevRingbufWrapper (Object)
• ChardevBackend (Object)
• ChardevReturn (Object)
• chardev-add (Command)
• chardev-change (Command)
• chardev-remove (Command)
• chardev-send-break (Command)
• VSERPORT_CHANGE (Event)
• Dump guest memory
• DumpGuestMemoryFormat (Enum)
• dump-guest-memory (Command)
• DumpStatus (Enum)
• DumpQueryResult (Object)
• query-dump (Command)
• DUMP_COMPLETED (Event)
• DumpGuestMemoryCapability (Object)
• query-dump-guest-memory-capability (Command)
• Net devices
• set_link (Command)
• netdev_add (Command)
• netdev_del (Command)
• NetLegacyNicOptions (Object)
• NetdevUserOptions (Object)
• NetdevTapOptions (Object)
• NetdevSocketOptions (Object)
• NetdevL2TPv3Options (Object)
• NetdevVdeOptions (Object)
• NetdevBridgeOptions (Object)
• NetdevHubPortOptions (Object)
• NetdevNetmapOptions (Object)
• NetdevVhostUserOptions (Object)
• NetdevVhostVDPAOptions (Object)
• NetdevVmnetHostOptions (Object)
• NetdevVmnetSharedOptions (Object)
• NetdevVmnetBridgedOptions (Object)
• NetdevStreamOptions (Object)
• NetdevDgramOptions (Object)
• NetClientDriver (Enum)
• Netdev (Object)
• RxState (Enum)
• RxFilterInfo (Object)
• query-rx-filter (Command)
• NIC_RX_FILTER_CHANGED (Event)
• AnnounceParameters (Object)
• announce-self (Command)
• FAILOVER_NEGOTIATED (Event)
• NETDEV_STREAM_CONNECTED (Event)
• NETDEV_STREAM_DISCONNECTED (Event)
• RDMA device
• RDMA_GID_STATUS_CHANGED (Event)
• Rocker switch device
• RockerSwitch (Object)
• query-rocker (Command)
• RockerPortDuplex (Enum)
• RockerPortAutoneg (Enum)
• RockerPort (Object)
• query-rocker-ports (Command)
• RockerOfDpaFlowKey (Object)
• RockerOfDpaFlowMask (Object)
• RockerOfDpaFlowAction (Object)
• RockerOfDpaFlow (Object)
• query-rocker-of-dpa-flows (Command)
• RockerOfDpaGroup (Object)
• query-rocker-of-dpa-groups (Command)
• TPM (trusted platform module) devices
• TpmModel (Enum)
• query-tpm-models (Command)
• TpmType (Enum)
• query-tpm-types (Command)
• TPMPassthroughOptions (Object)
• TPMEmulatorOptions (Object)
• TPMPassthroughOptionsWrapper (Object)
• TPMEmulatorOptionsWrapper (Object)
• TpmTypeOptions (Object)
• TPMInfo (Object)
• query-tpm (Command)
• Remote desktop
• DisplayProtocol (Enum)
• SetPasswordAction (Enum)
• SetPasswordOptions (Object)
• SetPasswordOptionsVnc (Object)
• set_password (Command)
• ExpirePasswordOptions (Object)
• ExpirePasswordOptionsVnc (Object)
• expire_password (Command)
• ImageFormat (Enum)
• screendump (Command)
• Spice
• VNC
• Input
• MouseInfo (Object)
• query-mice (Command)
• QKeyCode (Enum)
• KeyValueKind (Enum)
• IntWrapper (Object)
• QKeyCodeWrapper (Object)
• KeyValue (Object)
• send-key (Command)
• InputButton (Enum)
• InputAxis (Enum)
• InputKeyEvent (Object)
• InputBtnEvent (Object)
• InputMoveEvent (Object)
• InputEventKind (Enum)
• InputKeyEventWrapper (Object)
• InputBtnEventWrapper (Object)
• InputMoveEventWrapper (Object)
• InputEvent (Object)
• input-send-event (Command)
• DisplayGTK (Object)
• DisplayEGLHeadless (Object)
• DisplayDBus (Object)
• DisplayGLMode (Enum)
• DisplayCurses (Object)
• DisplayCocoa (Object)
• HotKeyMod (Enum)
• DisplaySDL (Object)
• DisplayType (Enum)
• DisplayOptions (Object)
• query-display-options (Command)
• DisplayReloadType (Enum)
• DisplayReloadOptionsVNC (Object)
• DisplayReloadOptions (Object)
• display-reload (Command)
• DisplayUpdateType (Enum)
• DisplayUpdateOptionsVNC (Object)
• DisplayUpdateOptions (Object)
• display-update (Command)
• User authorization
• QAuthZListPolicy (Enum)
• QAuthZListFormat (Enum)
• QAuthZListRule (Object)
• AuthZListProperties (Object)
• AuthZListFileProperties (Object)
• AuthZPAMProperties (Object)
• AuthZSimpleProperties (Object)
• Migration
• MigrationStats (Object)
• XBZRLECacheStats (Object)
• CompressionStats (Object)
• MigrationStatus (Enum)
• VfioStats (Object)
• MigrationInfo (Object)
• query-migrate (Command)
• MigrationCapability (Enum)
• MigrationCapabilityStatus (Object)
• migrate-set-capabilities (Command)
• query-migrate-capabilities (Command)
• MultiFDCompression (Enum)
• BitmapMigrationBitmapAliasTransform (Object)
• BitmapMigrationBitmapAlias (Object)
• BitmapMigrationNodeAlias (Object)
• MigrationParameter (Enum)
• MigrateSetParameters (Object)
• migrate-set-parameters (Command)
• MigrationParameters (Object)
• query-migrate-parameters (Command)
• client_migrate_info (Command)
• migrate-start-postcopy (Command)
• MIGRATION (Event)
• MIGRATION_PASS (Event)
• COLOMessage (Enum)
• COLOMode (Enum)
• FailoverStatus (Enum)
• COLO_EXIT (Event)
• COLOExitReason (Enum)
• x-colo-lost-heartbeat (Command)
• migrate_cancel (Command)
• migrate-continue (Command)
• migrate (Command)
• migrate-incoming (Command)
• xen-save-devices-state (Command)
• xen-set-global-dirty-log (Command)
• xen-load-devices-state (Command)
• xen-set-replication (Command)
• ReplicationStatus (Object)
• query-xen-replication-status (Command)
• xen-colo-do-checkpoint (Command)
• COLOStatus (Object)
• query-colo-status (Command)
• migrate-recover (Command)
• migrate-pause (Command)
• UNPLUG_PRIMARY (Event)
• DirtyRateVcpu (Object)
• DirtyRateStatus (Enum)
• DirtyRateMeasureMode (Enum)
• DirtyRateInfo (Object)
• calc-dirty-rate (Command)
• query-dirty-rate (Command)
• DirtyLimitInfo (Object)
• set-vcpu-dirty-limit (Command)
• cancel-vcpu-dirty-limit (Command)
• query-vcpu-dirty-limit (Command)
• snapshot-save (Command)
• snapshot-load (Command)
• snapshot-delete (Command)
• Transactions
• Abort (Object)
• ActionCompletionMode (Enum)
• TransactionActionKind (Enum)
• AbortWrapper (Object)
• BlockDirtyBitmapAddWrapper (Object)
• BlockDirtyBitmapWrapper (Object)
• BlockDirtyBitmapMergeWrapper (Object)
• BlockdevBackupWrapper (Object)
• BlockdevSnapshotWrapper (Object)
• BlockdevSnapshotInternalWrapper (Object)
• BlockdevSnapshotSyncWrapper (Object)
• DriveBackupWrapper (Object)
• TransactionAction (Object)
• TransactionProperties (Object)
• transaction (Command)
• Tracing
• TraceEventState (Enum)
• TraceEventInfo (Object)
• trace-event-get-state (Command)
• trace-event-set-state (Command)
• Compatibility policy
• CompatPolicyInput (Enum)
• CompatPolicyOutput (Enum)
• CompatPolicy (Object)
• QMP monitor control
• qmp_capabilities (Command)
• QMPCapability (Enum)
• VersionTriple (Object)
• VersionInfo (Object)
• query-version (Command)
• CommandInfo (Object)
• query-commands (Command)
• quit (Command)
• MonitorMode (Enum)
• MonitorOptions (Object)
• QMP introspection
• query-qmp-schema (Command)
• SchemaMetaType (Enum)
• SchemaInfo (Object)
• SchemaInfoBuiltin (Object)
• JSONType (Enum)
• SchemaInfoEnum (Object)
• SchemaInfoEnumMember (Object)
• SchemaInfoArray (Object)
• SchemaInfoObject (Object)
• SchemaInfoObjectMember (Object)
• SchemaInfoObjectVariant (Object)
• SchemaInfoAlternate (Object)
• SchemaInfoAlternateMember (Object)
• SchemaInfoCommand (Object)
• SchemaInfoEvent (Object)
• QEMU Object Model (QOM)
• ObjectPropertyInfo (Object)
• qom-list (Command)
• qom-get (Command)
• qom-set (Command)
• ObjectTypeInfo (Object)
• qom-list-types (Command)
• qom-list-properties (Command)
• CanHostSocketcanProperties (Object)
• ColoCompareProperties (Object)
• CryptodevBackendProperties (Object)
• CryptodevVhostUserProperties (Object)
• DBusVMStateProperties (Object)
• NetfilterInsert (Enum)
• NetfilterProperties (Object)
• FilterBufferProperties (Object)
• FilterDumpProperties (Object)
• FilterMirrorProperties (Object)
• FilterRedirectorProperties (Object)
• FilterRewriterProperties (Object)
• InputBarrierProperties (Object)
• InputLinuxProperties (Object)
• EventLoopBaseProperties (Object)
• IothreadProperties (Object)
• MainLoopProperties (Object)
• MemoryBackendProperties (Object)
• MemoryBackendFileProperties (Object)
• MemoryBackendMemfdProperties (Object)
• MemoryBackendEpcProperties (Object)
• PrManagerHelperProperties (Object)
• QtestProperties (Object)
• RemoteObjectProperties (Object)
• VfioUserServerProperties (Object)
• RngProperties (Object)
• RngEgdProperties (Object)
• RngRandomProperties (Object)
• SevGuestProperties (Object)
• ThreadContextProperties (Object)
• ObjectType (Enum)
• ObjectOptions (Object)
• object-add (Command)
• object-del (Command)
• Device infrastructure (qdev)
• device-list-properties (Command)
• device_add (Command)
• device_del (Command)
• DEVICE_DELETED (Event)
• DEVICE_UNPLUG_GUEST_ERROR (Event)
• Machines
• SysEmuTarget (Enum)
• CpuS390State (Enum)
• CpuInfoS390 (Object)
• CpuInfoFast (Object)
• query-cpus-fast (Command)
• MachineInfo (Object)
• query-machines (Command)
• CurrentMachineParams (Object)
• query-current-machine (Command)
• TargetInfo (Object)
• query-target (Command)
• UuidInfo (Object)
• query-uuid (Command)
• GuidInfo (Object)
• query-vm-generation-id (Command)
• system_reset (Command)
• system_powerdown (Command)
• system_wakeup (Command)
• LostTickPolicy (Enum)
• inject-nmi (Command)
• KvmInfo (Object)
• query-kvm (Command)
• NumaOptionsType (Enum)
• NumaOptions (Object)
• NumaNodeOptions (Object)
• NumaDistOptions (Object)
• CXLFixedMemoryWindowOptions (Object)
• CXLFMWProperties (Object)
• X86CPURegister32 (Enum)
• X86CPUFeatureWordInfo (Object)
• DummyForceArrays (Object)
• NumaCpuOptions (Object)
• HmatLBMemoryHierarchy (Enum)
• HmatLBDataType (Enum)
• NumaHmatLBOptions (Object)
• HmatCacheAssociativity (Enum)
• HmatCacheWritePolicy (Enum)
• NumaHmatCacheOptions (Object)
• memsave (Command)
• pmemsave (Command)
• Memdev (Object)
• query-memdev (Command)
• CpuInstanceProperties (Object)
• HotpluggableCPU (Object)
• query-hotpluggable-cpus (Command)
• set-numa-node (Command)
• balloon (Command)
• BalloonInfo (Object)
• query-balloon (Command)
• BALLOON_CHANGE (Event)
• MemoryInfo (Object)
• query-memory-size-summary (Command)
• PCDIMMDeviceInfo (Object)
• VirtioPMEMDeviceInfo (Object)
• VirtioMEMDeviceInfo (Object)
• SgxEPCDeviceInfo (Object)
• MemoryDeviceInfoKind (Enum)
• PCDIMMDeviceInfoWrapper (Object)
• VirtioPMEMDeviceInfoWrapper (Object)
• VirtioMEMDeviceInfoWrapper (Object)
• SgxEPCDeviceInfoWrapper (Object)
• MemoryDeviceInfo (Object)
• SgxEPC (Object)
• SgxEPCProperties (Object)
• query-memory-devices (Command)
• MEMORY_DEVICE_SIZE_CHANGE (Event)
• MEM_UNPLUG_ERROR (Event)
• BootConfiguration (Object)
• SMPConfiguration (Object)
• x-query-irq (Command)
• x-query-jit (Command)
• x-query-numa (Command)
• x-query-opcount (Command)
• x-query-profile (Command)
• x-query-ramblock (Command)
• x-query-rdma (Command)
• x-query-roms (Command)
• x-query-usb (Command)
• SmbiosEntryPointType (Enum)
• MemorySizeConfiguration (Object)
• dumpdtb (Command)
• CpuModelInfo (Object)
• CpuModelExpansionType (Enum)
• CpuModelCompareResult (Enum)
• CpuModelBaselineInfo (Object)
• CpuModelCompareInfo (Object)
• query-cpu-model-comparison (Command)
• query-cpu-model-baseline (Command)
• CpuModelExpansionInfo (Object)
• query-cpu-model-expansion (Command)
• CpuDefinitionInfo (Object)
• query-cpu-definitions (Command)
• Record/replay
• ReplayMode (Enum)
• ReplayInfo (Object)
• query-replay (Command)
• replay-break (Command)
• replay-delete-break (Command)
• replay-seek (Command)
• Yank feature
• YankInstanceType (Enum)
• YankInstanceBlockNode (Object)
• YankInstanceChardev (Object)
• YankInstance (Object)
• yank (Command)
• query-yank (Command)
• Miscellanea
• add_client (Command)
• NameInfo (Object)
• query-name (Command)
• IOThreadInfo (Object)
• query-iothreads (Command)
• stop (Command)
• cont (Command)
• x-exit-preconfig (Command)
• human-monitor-command (Command)
• getfd (Command)
• closefd (Command)
• AddfdInfo (Object)
• add-fd (Command)
• remove-fd (Command)
• FdsetFdInfo (Object)
• FdsetInfo (Object)
• query-fdsets (Command)
• CommandLineParameterType (Enum)
• CommandLineParameterInfo (Object)
• CommandLineOptionInfo (Object)
• query-command-line-options (Command)
• RTC_CHANGE (Event)
• VFU_CLIENT_HANGUP (Event)
• rtc-reset-reinjection (Command)
• SevState (Enum)
• SevInfo (Object)
• query-sev (Command)
• SevLaunchMeasureInfo (Object)
• query-sev-launch-measure (Command)
• SevCapability (Object)
• query-sev-capabilities (Command)
• sev-inject-launch-secret (Command)
• SevAttestationReport (Object)
• query-sev-attestation-report (Command)
• dump-skeys (Command)
• GICCapability (Object)
• query-gic-capabilities (Command)
• SGXEPCSection (Object)
• SGXInfo (Object)
• query-sgx (Command)
• query-sgx-capabilities (Command)
• Audio
• AudiodevPerDirectionOptions (Object)
• AudiodevGenericOptions (Object)
• AudiodevAlsaPerDirectionOptions (Object)
• AudiodevAlsaOptions (Object)
• AudiodevSndioOptions (Object)
• AudiodevCoreaudioPerDirectionOptions (Object)
• AudiodevCoreaudioOptions (Object)
• AudiodevDsoundOptions (Object)
• AudiodevJackPerDirectionOptions (Object)
• AudiodevJackOptions (Object)
• AudiodevOssPerDirectionOptions (Object)
• AudiodevOssOptions (Object)
• AudiodevPaPerDirectionOptions (Object)
• AudiodevPaOptions (Object)
• AudiodevSdlPerDirectionOptions (Object)
• AudiodevSdlOptions (Object)
• AudiodevWavOptions (Object)
• AudioFormat (Enum)
• AudiodevDriver (Enum)
• Audiodev (Object)
• ACPI
• AcpiTableOptions (Object)
• ACPISlotType (Enum)
• ACPIOSTInfo (Object)
• query-acpi-ospm-status (Command)
• ACPI_DEVICE_OST (Event)
• PCI
• PciMemoryRange (Object)
• PciMemoryRegion (Object)
• PciBusInfo (Object)
• PciBridgeInfo (Object)
• PciDeviceClass (Object)
• PciDeviceId (Object)
• PciDeviceInfo (Object)
• PciInfo (Object)
• query-pci (Command)
• Statistics
• StatsType (Enum)
• StatsUnit (Enum)
• StatsProvider (Enum)
• StatsTarget (Enum)
• StatsRequest (Object)
• StatsVCPUFilter (Object)
• StatsFilter (Object)
• StatsValue (Alternate)
• Stats (Object)
• StatsResult (Object)
• query-stats (Command)
• StatsSchemaValue (Object)
• StatsSchema (Object)
• query-stats-schemas (Command)
• Virtio devices
• VirtioInfo (Object)
• x-query-virtio (Command)
• VhostStatus (Object)
• VirtioStatus (Object)
• x-query-virtio-status (Command)
• VirtioDeviceStatus (Object)
• VhostDeviceProtocols (Object)
• VirtioDeviceFeatures (Object)
• VirtQueueStatus (Object)
• x-query-virtio-queue-status (Command)
• VirtVhostQueueStatus (Object)
• x-query-virtio-vhost-queue-status (Command)
• VirtioRingDesc (Object)
• VirtioRingAvail (Object)
• VirtioRingUsed (Object)
• VirtioQueueElement (Object)
• x-query-virtio-queue-element (Command)
INTRODUCTION
This document describes all commands currently supported by QMP.
Most of the time their usage is exactly the same as in the user Moni-
tor, this means that any other document which also describe commands
(the manpage, QEMU's manual, etc) can and should be consulted.
QMP has two types of commands: regular and query commands. Regular com-
mands usually change the Virtual Machine's state someway, while query
commands just return information. The sections below are divided ac-
cordingly.
It's important to observe that all communication examples are formatted
in a reader-friendly way, so that they're easier to understand. How-
ever, in real protocol usage, they're emitted as a single line.
Also, the following notation is used to denote data flow:
Example:
-> data issued by the Client
<- Server data response
Please, refer to the QMP specification (docs/interop/qmp-spec.txt) for
detailed information on the Server command and response formats.
STABILITY CONSIDERATIONS
The current QMP command set (described in this file) may be useful for
a number of use cases, however it's limited and several commands have
bad defined semantics, specially with regard to command completion.
These problems are going to be solved incrementally in the next QEMU
releases and we're going to establish a deprecation policy for badly
defined commands.
If you're planning to adopt QMP, please observe the following:
1. The deprecation policy will take effect and be documented soon,
please check the documentation of each used command as soon as a
new release of QEMU is available
2. DO NOT rely on anything which is not explicit documented
3. Errors, in special, are not documented. Applications should NOT
check for specific errors classes or data (it's strongly recom-
mended to only check for the "error" key)
QMP ERRORS
QapiErrorClass (Enum)
QEMU error classes
Values
GenericError
this is used for errors that don't require a specific error
class. This should be the default case for most errors
CommandNotFound
the requested command has not been found
DeviceNotActive
a device has failed to be become active
DeviceNotFound
the requested device has not been found
KVMMissingCap
the requested operation can't be fulfilled because a required
KVM capability is missing
Since
1.2
COMMON DATA TYPES
IoOperationType (Enum)
An enumeration of the I/O operation types
Values
read read operation
write write operation
Since
2.1
OnOffAuto (Enum)
An enumeration of three options: on, off, and auto
Values
auto QEMU selects the value between on and off
on Enabled
off Disabled
Since
2.2
OnOffSplit (Enum)
An enumeration of three values: on, off, and split
Values
on Enabled
off Disabled
split Mixed
Since
2.6
String (Object)
A fat type wrapping 'str', to be embedded in lists.
Members
str: string
Not documented
Since
1.2
StrOrNull (Alternate)
This is a string value or the explicit lack of a string (null pointer
in C). Intended for cases when 'optional absent' already has a differ-
ent meaning.
Members
s: string
the string value
n: null
no string value
Since
2.10
OffAutoPCIBAR (Enum)
An enumeration of options for specifying a PCI BAR
Values
off The specified feature is disabled
auto The PCI BAR for the feature is automatically selected
bar0 PCI BAR0 is used for the feature
bar1 PCI BAR1 is used for the feature
bar2 PCI BAR2 is used for the feature
bar3 PCI BAR3 is used for the feature
bar4 PCI BAR4 is used for the feature
bar5 PCI BAR5 is used for the feature
Since
2.12
PCIELinkSpeed (Enum)
An enumeration of PCIe link speeds in units of GT/s
Values
2_5 2.5GT/s
5 5.0GT/s
8 8.0GT/s
16 16.0GT/s
Since
4.0
PCIELinkWidth (Enum)
An enumeration of PCIe link width
Values
1 x1
2 x2
4 x4
8 x8
12 x12
16 x16
32 x32
Since
4.0
HostMemPolicy (Enum)
Host memory policy types
Values
default
restore default policy, remove any nondefault policy
preferred
set the preferred host nodes for allocation
bind a strict policy that restricts memory allocation to the host
nodes specified
interleave
memory allocations are interleaved across the set of host nodes
specified
Since
2.1
NetFilterDirection (Enum)
Indicates whether a netfilter is attached to a netdev's transmit queue
or receive queue or both.
Values
all the filter is attached both to the receive and the transmit
queue of the netdev (default).
rx the filter is attached to the receive queue of the netdev, where
it will receive packets sent to the netdev.
tx the filter is attached to the transmit queue of the netdev,
where it will receive packets sent by the netdev.
Since
2.5
GrabToggleKeys (Enum)
Keys to toggle input-linux between host and guest.
Values
ctrl-ctrl
Not documented
alt-alt
Not documented
shift-shift
Not documented
meta-meta
Not documented
scrolllock
Not documented
ctrl-scrolllock
Not documented
Since
4.0
HumanReadableText (Object)
Members
human-readable-text: string
Formatted output intended for humans.
Since
6.2
SOCKET DATA TYPES
NetworkAddressFamily (Enum)
The network address family
Values
ipv4 IPV4 family
ipv6 IPV6 family
unix unix socket
vsock vsock family (since 2.8)
unknown
otherwise
Since
2.1
InetSocketAddressBase (Object)
Members
host: string
host part of the address
port: string
port part of the address
InetSocketAddress (Object)
Captures a socket address or address range in the Internet namespace.
Members
numeric: boolean (optional)
true if the host/port are guaranteed to be numeric, false if
name resolution should be attempted. Defaults to false. (Since
2.9)
to: int (optional)
If present, this is range of possible addresses, with port be-
tween port and to.
ipv4: boolean (optional)
whether to accept IPv4 addresses, default try both IPv4 and IPv6
ipv6: boolean (optional)
whether to accept IPv6 addresses, default try both IPv4 and IPv6
keep-alive: boolean (optional)
enable keep-alive when connecting to this socket. Not supported
for passive sockets. (Since 4.2)
mptcp: boolean (optional) (If: HAVE_IPPROTO_MPTCP)
enable multi-path TCP. (Since 6.1)
The members of InetSocketAddressBase
Since
1.3
UnixSocketAddress (Object)
Captures a socket address in the local ("Unix socket") namespace.
Members
path: string
filesystem path to use
abstract: boolean (optional) (If: CONFIG_LINUX)
if true, this is a Linux abstract socket address. path will be
prefixed by a null byte, and optionally padded with null bytes.
Defaults to false. (Since 5.1)
tight: boolean (optional) (If: CONFIG_LINUX)
if false, pad an abstract socket address with enough null bytes
to make it fill struct sockaddr_un member sun_path. Defaults to
true. (Since 5.1)
Since
1.3
VsockSocketAddress (Object)
Captures a socket address in the vsock namespace.
Members
cid: string
unique host identifier
port: string
port
Note
string types are used to allow for possible future hostname or service
resolution support.
Since
2.8
InetSocketAddressWrapper (Object)
Members
data: InetSocketAddress
Not documented
Since
1.3
UnixSocketAddressWrapper (Object)
Members
data: UnixSocketAddress
Not documented
Since
1.3
VsockSocketAddressWrapper (Object)
Members
data: VsockSocketAddress
Not documented
Since
2.8
StringWrapper (Object)
Members
data: String
Not documented
Since
1.3
SocketAddressLegacy (Object)
Captures the address of a socket, which could also be a named file de-
scriptor
Members
type: SocketAddressType
Not documented
The members of InetSocketAddressWrapper when type is "inet"
The members of UnixSocketAddressWrapper when type is "unix"
The members of VsockSocketAddressWrapper when type is "vsock"
The members of StringWrapper when type is "fd"
Note
This type is deprecated in favor of SocketAddress. The difference be-
tween SocketAddressLegacy and SocketAddress is that the latter has
fewer {} on the wire.
Since
1.3
SocketAddressType (Enum)
Available SocketAddress types
Values
inet Internet address
unix Unix domain socket
vsock VMCI address
fd decimal is for file descriptor number, otherwise a file descrip-
tor name. Named file descriptors are permitted in monitor com-
mands, in combination with the 'getfd' command. Decimal file de-
scriptors are permitted at startup or other contexts where no
monitor context is active.
Since
2.9
SocketAddress (Object)
Captures the address of a socket, which could also be a named file de-
scriptor
Members
type: SocketAddressType
Transport type
The members of InetSocketAddress when type is "inet"
The members of UnixSocketAddress when type is "unix"
The members of VsockSocketAddress when type is "vsock"
The members of String when type is "fd"
Since
2.9
VM RUN STATE
RunState (Enum)
An enumeration of VM run states.
Values
debug QEMU is running on a debugger
finish-migrate
guest is paused to finish the migration process
inmigrate
guest is paused waiting for an incoming migration. Note that
this state does not tell whether the machine will start at the
end of the migration. This depends on the command-line -S op-
tion and any invocation of 'stop' or 'cont' that has happened
since QEMU was started.
internal-error
An internal error that prevents further guest execution has oc-
curred
io-error
the last IOP has failed and the device is configured to pause on
I/O errors
paused guest has been paused via the 'stop' command
postmigrate
guest is paused following a successful 'migrate'
prelaunch
QEMU was started with -S and guest has not started
restore-vm
guest is paused to restore VM state
running
guest is actively running
save-vm
guest is paused to save the VM state
shutdown
guest is shut down (and -no-shutdown is in use)
suspended
guest is suspended (ACPI S3)
watchdog
the watchdog action is configured to pause and has been trig-
gered
guest-panicked
guest has been panicked as a result of guest OS panic
colo guest is paused to save/restore VM state under colo checkpoint,
VM can not get into this state unless colo capability is enabled
for migration. (since 2.8)
ShutdownCause (Enum)
An enumeration of reasons for a Shutdown.
Values
none No shutdown request pending
host-error
An error prevents further use of guest
host-qmp-quit
Reaction to the QMP command 'quit'
host-qmp-system-reset
Reaction to the QMP command 'system_reset'
host-signal
Reaction to a signal, such as SIGINT
host-ui
Reaction to a UI event, like window close
guest-shutdown
Guest shutdown/suspend request, via ACPI or other hardware-spe-
cific means
guest-reset
Guest reset request, and command line turns that into a shutdown
guest-panic
Guest panicked, and command line turns that into a shutdown
subsystem-reset
Partial guest reset that does not trigger QMP events and ignores
--no-reboot. This is useful for sanitizing hypercalls on s390
that are used during kexec/kdump/boot
snapshot-load
A snapshot is being loaded by the record & replay subsystem.
This value is used only within QEMU. It doesn't occur in QMP.
(since 7.2)
StatusInfo (Object)
Information about VCPU run state
Members
running: boolean
true if all VCPUs are runnable, false if not runnable
singlestep: boolean
true if VCPUs are in single-step mode
status: RunState
the virtual machine RunState
Since
0.14
Notes
singlestep is enabled through the GDB stub
query-status (Command)
Query the run status of all VCPUs
Returns
StatusInfo reflecting all VCPUs
Since
0.14
Example
-> { "execute": "query-status" }
<- { "return": { "running": true,
"singlestep": false,
"status": "running" } }
SHUTDOWN (Event)
Emitted when the virtual machine has shut down, indicating that qemu is
about to exit.
Arguments
guest: boolean
If true, the shutdown was triggered by a guest request (such as
a guest-initiated ACPI shutdown request or other hardware-spe-
cific action) rather than a host request (such as sending qemu a
SIGINT). (since 2.10)
reason: ShutdownCause
The ShutdownCause which resulted in the SHUTDOWN. (since 4.0)
Note
If the command-line option "-no-shutdown" has been specified, qemu will
not exit, and a STOP event will eventually follow the SHUTDOWN event
Since
0.12
Example
<- { "event": "SHUTDOWN",
"data": { "guest": true, "reason": "guest-shutdown" },
"timestamp": { "seconds": 1267040730, "microseconds": 682951 } }
POWERDOWN (Event)
Emitted when the virtual machine is powered down through the power con-
trol system, such as via ACPI.
Since
0.12
Example
<- { "event": "POWERDOWN",
"timestamp": { "seconds": 1267040730, "microseconds": 682951 } }
RESET (Event)
Emitted when the virtual machine is reset
Arguments
guest: boolean
If true, the reset was triggered by a guest request (such as a
guest-initiated ACPI reboot request or other hardware-specific
action) rather than a host request (such as the QMP command sys-
tem_reset). (since 2.10)
reason: ShutdownCause
The ShutdownCause of the RESET. (since 4.0)
Since
0.12
Example
<- { "event": "RESET",
"data": { "guest": false, "reason": "guest-reset" },
"timestamp": { "seconds": 1267041653, "microseconds": 9518 } }
STOP (Event)
Emitted when the virtual machine is stopped
Since
0.12
Example
<- { "event": "STOP",
"timestamp": { "seconds": 1267041730, "microseconds": 281295 } }
RESUME (Event)
Emitted when the virtual machine resumes execution
Since
0.12
Example
<- { "event": "RESUME",
"timestamp": { "seconds": 1271770767, "microseconds": 582542 } }
SUSPEND (Event)
Emitted when guest enters a hardware suspension state, for example, S3
state, which is sometimes called standby state
Since
1.1
Example
<- { "event": "SUSPEND",
"timestamp": { "seconds": 1344456160, "microseconds": 309119 } }
SUSPEND_DISK (Event)
Emitted when guest enters a hardware suspension state with data saved
on disk, for example, S4 state, which is sometimes called hibernate
state
Note
QEMU shuts down (similar to event SHUTDOWN) when entering this state
Since
1.2
Example
<- { "event": "SUSPEND_DISK",
"timestamp": { "seconds": 1344456160, "microseconds": 309119 } }
WAKEUP (Event)
Emitted when the guest has woken up from suspend state and is running
Since
1.1
Example
<- { "event": "WAKEUP",
"timestamp": { "seconds": 1344522075, "microseconds": 745528 } }
WATCHDOG (Event)
Emitted when the watchdog device's timer is expired
Arguments
action: WatchdogAction
action that has been taken
Note
If action is "reset", "shutdown", or "pause" the WATCHDOG event is fol-
lowed respectively by the RESET, SHUTDOWN, or STOP events
Note
This event is rate-limited.
Since
0.13
Example
<- { "event": "WATCHDOG",
"data": { "action": "reset" },
"timestamp": { "seconds": 1267061043, "microseconds": 959568 } }
WatchdogAction (Enum)
An enumeration of the actions taken when the watchdog device's timer is
expired
Values
reset system resets
shutdown
system shutdown, note that it is similar to powerdown, which
tries to set to system status and notify guest
poweroff
system poweroff, the emulator program exits
pause system pauses, similar to stop
debug system enters debug state
none nothing is done
inject-nmi
a non-maskable interrupt is injected into the first VCPU (all
VCPUS on x86) (since 2.4)
Since
2.1
RebootAction (Enum)
Possible QEMU actions upon guest reboot
Values
reset Reset the VM
shutdown
Shutdown the VM and exit, according to the shutdown action
Since
6.0
ShutdownAction (Enum)
Possible QEMU actions upon guest shutdown
Values
poweroff
Shutdown the VM and exit
pause pause the VM
Since
6.0
PanicAction (Enum)
Values
none Continue VM execution
pause Pause the VM
shutdown
Shutdown the VM and exit, according to the shutdown action
exit-failure
Shutdown the VM and exit with nonzero status (since 7.1)
Since
6.0
watchdog-set-action (Command)
Set watchdog action
Arguments
action: WatchdogAction
Not documented
Since
2.11
set-action (Command)
Set the actions that will be taken by the emulator in response to guest
events.
Arguments
reboot: RebootAction (optional)
RebootAction action taken on guest reboot.
shutdown: ShutdownAction (optional)
ShutdownAction action taken on guest shutdown.
panic: PanicAction (optional)
PanicAction action taken on guest panic.
watchdog: WatchdogAction (optional)
WatchdogAction action taken when watchdog timer expires .
Returns
Nothing on success.
Since
6.0
Example
-> { "execute": "set-action",
"arguments": { "reboot": "shutdown",
"shutdown" : "pause",
"panic": "pause",
"watchdog": "inject-nmi" } }
<- { "return": {} }
GUEST_PANICKED (Event)
Emitted when guest OS panic is detected
Arguments
action: GuestPanicAction
action that has been taken, currently always "pause"
info: GuestPanicInformation (optional)
information about a panic (since 2.9)
Since
1.5
Example
<- { "event": "GUEST_PANICKED",
"data": { "action": "pause" },
"timestamp": { "seconds": 1648245231, "microseconds": 900001 } }
GUEST_CRASHLOADED (Event)
Emitted when guest OS crash loaded is detected
Arguments
action: GuestPanicAction
action that has been taken, currently always "run"
info: GuestPanicInformation (optional)
information about a panic
Since
5.0
Example
<- { "event": "GUEST_CRASHLOADED",
"data": { "action": "run" },
"timestamp": { "seconds": 1648245259, "microseconds": 893771 } }
GuestPanicAction (Enum)
An enumeration of the actions taken when guest OS panic is detected
Values
pause system pauses
poweroff
Not documented
run Not documented
Since
2.1 (poweroff since 2.8, run since 5.0)
GuestPanicInformationType (Enum)
An enumeration of the guest panic information types
Values
hyper-v
hyper-v guest panic information type
s390 s390 guest panic information type (Since: 2.12)
Since
2.9
GuestPanicInformation (Object)
Information about a guest panic
Members
type: GuestPanicInformationType
Crash type that defines the hypervisor specific information
The members of GuestPanicInformationHyperV when type is "hyper-v"
The members of GuestPanicInformationS390 when type is "s390"
Since
2.9
GuestPanicInformationHyperV (Object)
Hyper-V specific guest panic information (HV crash MSRs)
Members
arg1: int
Not documented
arg2: int
Not documented
arg3: int
Not documented
arg4: int
Not documented
arg5: int
Not documented
Since
2.9
S390CrashReason (Enum)
Reason why the CPU is in a crashed state.
Values
unknown
no crash reason was set
disabled-wait
the CPU has entered a disabled wait state
extint-loop
clock comparator or cpu timer interrupt with new PSW enabled for
external interrupts
pgmint-loop
program interrupt with BAD new PSW
opint-loop
operation exception interrupt with invalid code at the program
interrupt new PSW
Since
2.12
GuestPanicInformationS390 (Object)
S390 specific guest panic information (PSW)
Members
core: int
core id of the CPU that crashed
psw-mask: int
control fields of guest PSW
psw-addr: int
guest instruction address
reason: S390CrashReason
guest crash reason
Since
2.12
MEMORY_FAILURE (Event)
Emitted when a memory failure occurs on host side.
Arguments
recipient: MemoryFailureRecipient
recipient is defined as MemoryFailureRecipient.
action: MemoryFailureAction
action that has been taken. action is defined as MemoryFailure-
Action.
flags: MemoryFailureFlags
flags for MemoryFailureAction. action is defined as MemoryFail-
ureFlags.
Since
5.2
Example
<- { "event": "MEMORY_FAILURE",
"data": { "recipient": "hypervisor",
"action": "fatal",
"flags": { "action-required": false,
"recursive": false } },
"timestamp": { "seconds": 1267061043, "microseconds": 959568 } }
MemoryFailureRecipient (Enum)
Hardware memory failure occurs, handled by recipient.
Values
hypervisor
memory failure at QEMU process address space. (none guest mem-
ory, but used by QEMU itself).
guest memory failure at guest memory,
Since
5.2
MemoryFailureAction (Enum)
Actions taken by QEMU in response to a hardware memory failure.
Values
ignore the memory failure could be ignored. This will only be the case
for action-optional failures.
inject memory failure occurred in guest memory, the guest enabled MCE
handling mechanism, and QEMU could inject the MCE into the guest
successfully.
fatal the failure is unrecoverable. This occurs for action-required
failures if the recipient is the hypervisor; QEMU will exit.
reset the failure is unrecoverable but confined to the guest. This
occurs if the recipient is a guest guest which is not ready to
handle memory failures.
Since
5.2
MemoryFailureFlags (Object)
Additional information on memory failures.
Members
action-required: boolean
whether a memory failure event is action-required or action-op-
tional (e.g. a failure during memory scrub).
recursive: boolean
whether the failure occurred while the previous failure was
still in progress.
Since
5.2
NotifyVmexitOption (Enum)
An enumeration of the options specified when enabling notify VM exit
Values
run enable the feature, do nothing and continue if the notify VM
exit happens.
internal-error
enable the feature, raise a internal error if the notify VM exit
happens.
disable
disable the feature.
Since
7.2
CRYPTOGRAPHY
QCryptoTLSCredsEndpoint (Enum)
The type of network endpoint that will be using the credentials. Most
types of credential require different setup / structures depending on
whether they will be used in a server versus a client.
Values
client the network endpoint is acting as the client
server the network endpoint is acting as the server
Since
2.5
QCryptoSecretFormat (Enum)
The data format that the secret is provided in
Values
raw raw bytes. When encoded in JSON only valid UTF-8 sequences can
be used
base64 arbitrary base64 encoded binary data
Since
2.6
QCryptoHashAlgorithm (Enum)
The supported algorithms for computing content digests
Values
md5 MD5. Should not be used in any new code, legacy compat only
sha1 SHA-1. Should not be used in any new code, legacy compat only
sha224 SHA-224. (since 2.7)
sha256 SHA-256. Current recommended strong hash.
sha384 SHA-384. (since 2.7)
sha512 SHA-512. (since 2.7)
ripemd160
RIPEMD-160. (since 2.7)
Since
2.6
QCryptoCipherAlgorithm (Enum)
The supported algorithms for content encryption ciphers
Values
aes-128
AES with 128 bit / 16 byte keys
aes-192
AES with 192 bit / 24 byte keys
aes-256
AES with 256 bit / 32 byte keys
des DES with 56 bit / 8 byte keys. Do not use except in VNC. (since
6.1)
3des 3DES(EDE) with 192 bit / 24 byte keys (since 2.9)
cast5-128
Cast5 with 128 bit / 16 byte keys
serpent-128
Serpent with 128 bit / 16 byte keys
serpent-192
Serpent with 192 bit / 24 byte keys
serpent-256
Serpent with 256 bit / 32 byte keys
twofish-128
Twofish with 128 bit / 16 byte keys
twofish-192
Twofish with 192 bit / 24 byte keys
twofish-256
Twofish with 256 bit / 32 byte keys
Since
2.6
QCryptoCipherMode (Enum)
The supported modes for content encryption ciphers
Values
ecb Electronic Code Book
cbc Cipher Block Chaining
xts XEX with tweaked code book and ciphertext stealing
ctr Counter (Since 2.8)
Since
2.6
QCryptoIVGenAlgorithm (Enum)
The supported algorithms for generating initialization vectors for full
disk encryption. The 'plain' generator should not be used for disks
with sector numbers larger than 2^32, except where compatibility with
pre-existing Linux dm-crypt volumes is required.
Values
plain 64-bit sector number truncated to 32-bits
plain64
64-bit sector number
essiv 64-bit sector number encrypted with a hash of the encryption key
Since
2.6
QCryptoBlockFormat (Enum)
The supported full disk encryption formats
Values
qcow QCow/QCow2 built-in AES-CBC encryption. Use only for liberating
data from old images.
luks LUKS encryption format. Recommended for new images
Since
2.6
QCryptoBlockOptionsBase (Object)
The common options that apply to all full disk encryption formats
Members
format: QCryptoBlockFormat
the encryption format
Since
2.6
QCryptoBlockOptionsQCow (Object)
The options that apply to QCow/QCow2 AES-CBC encryption format
Members
key-secret: string (optional)
the ID of a QCryptoSecret object providing the decryption key.
Mandatory except when probing image for metadata only.
Since
2.6
QCryptoBlockOptionsLUKS (Object)
The options that apply to LUKS encryption format
Members
key-secret: string (optional)
the ID of a QCryptoSecret object providing the decryption key.
Mandatory except when probing image for metadata only.
Since
2.6
QCryptoBlockCreateOptionsLUKS (Object)
The options that apply to LUKS encryption format initialization
Members
cipher-alg: QCryptoCipherAlgorithm (optional)
the cipher algorithm for data encryption Currently defaults to
'aes-256'.
cipher-mode: QCryptoCipherMode (optional)
the cipher mode for data encryption Currently defaults to 'xts'
ivgen-alg: QCryptoIVGenAlgorithm (optional)
the initialization vector generator Currently defaults to
'plain64'
ivgen-hash-alg: QCryptoHashAlgorithm (optional)
the initialization vector generator hash Currently defaults to
'sha256'
hash-alg: QCryptoHashAlgorithm (optional)
the master key hash algorithm Currently defaults to 'sha256'
iter-time: int (optional)
number of milliseconds to spend in PBKDF passphrase processing.
Currently defaults to 2000. (since 2.8)
The members of QCryptoBlockOptionsLUKS
Since
2.6
QCryptoBlockOpenOptions (Object)
The options that are available for all encryption formats when opening
an existing volume
Members
The members of QCryptoBlockOptionsBase
The members of QCryptoBlockOptionsQCow when format is "qcow"
The members of QCryptoBlockOptionsLUKS when format is "luks"
Since
2.6
QCryptoBlockCreateOptions (Object)
The options that are available for all encryption formats when initial-
izing a new volume
Members
The members of QCryptoBlockOptionsBase
The members of QCryptoBlockOptionsQCow when format is "qcow"
The members of QCryptoBlockCreateOptionsLUKS when format is "luks"
Since
2.6
QCryptoBlockInfoBase (Object)
The common information that applies to all full disk encryption formats
Members
format: QCryptoBlockFormat
the encryption format
Since
2.7
QCryptoBlockInfoLUKSSlot (Object)
Information about the LUKS block encryption key slot options
Members
active: boolean
whether the key slot is currently in use
key-offset: int
offset to the key material in bytes
iters: int (optional)
number of PBKDF2 iterations for key material
stripes: int (optional)
number of stripes for splitting key material
Since
2.7
QCryptoBlockInfoLUKS (Object)
Information about the LUKS block encryption options
Members
cipher-alg: QCryptoCipherAlgorithm
the cipher algorithm for data encryption
cipher-mode: QCryptoCipherMode
the cipher mode for data encryption
ivgen-alg: QCryptoIVGenAlgorithm
the initialization vector generator
ivgen-hash-alg: QCryptoHashAlgorithm (optional)
the initialization vector generator hash
hash-alg: QCryptoHashAlgorithm
the master key hash algorithm
payload-offset: int
offset to the payload data in bytes
master-key-iters: int
number of PBKDF2 iterations for key material
uuid: string
unique identifier for the volume
slots: array of QCryptoBlockInfoLUKSSlot
information about each key slot
Since
2.7
QCryptoBlockInfo (Object)
Information about the block encryption options
Members
The members of QCryptoBlockInfoBase
The members of QCryptoBlockInfoLUKS when format is "luks"
Since
2.7
QCryptoBlockLUKSKeyslotState (Enum)
Defines state of keyslots that are affected by the update
Values
active The slots contain the given password and marked as active
inactive
The slots are erased (contain garbage) and marked as inactive
Since
5.1
QCryptoBlockAmendOptionsLUKS (Object)
This struct defines the update parameters that activate/de-activate set
of keyslots
Members
state: QCryptoBlockLUKSKeyslotState
the desired state of the keyslots
new-secret: string (optional)
The ID of a QCryptoSecret object providing the password to be
written into added active keyslots
old-secret: string (optional)
Optional (for deactivation only) If given will deactivate all
keyslots that match password located in QCryptoSecret with this
ID
iter-time: int (optional)
Optional (for activation only) Number of milliseconds to spend
in PBKDF passphrase processing for the newly activated keyslot.
Currently defaults to 2000.
keyslot: int (optional)
Optional. ID of the keyslot to activate/deactivate. For keyslot
activation, keyslot should not be active already (this is unsafe
to update an active keyslot), but possible if 'force' parameter
is given. If keyslot is not given, first free keyslot will be
written.
For keyslot deactivation, this parameter specifies the exact
keyslot to deactivate
secret: string (optional)
Optional. The ID of a QCryptoSecret object providing the pass-
word to use to retrieve current master key. Defaults to the
same secret that was used to open the image
Since
5.1
QCryptoBlockAmendOptions (Object)
The options that are available for all encryption formats when amending
encryption settings
Members
The members of QCryptoBlockOptionsBase
The members of QCryptoBlockAmendOptionsLUKS when format is "luks"
Since
5.1
SecretCommonProperties (Object)
Properties for objects of classes derived from secret-common.
Members
loaded: boolean (optional)
if true, the secret is loaded immediately when applying this op-
tion and will probably fail when processing the next option.
Don't use; only provided for compatibility. (default: false)
format: QCryptoSecretFormat (optional)
the data format that the secret is provided in (default: raw)
keyid: string (optional)
the name of another secret that should be used to decrypt the
provided data. If not present, the data is assumed to be unen-
crypted.
iv: string (optional)
the random initialization vector used for encryption of this
particular secret. Should be a base64 encrypted string of the
16-byte IV. Mandatory if keyid is given. Ignored if keyid is ab-
sent.
Features
deprecated
Member loaded is deprecated. Setting true doesn't make sense,
and false is already the default.
Since
2.6
SecretProperties (Object)
Properties for secret objects.
Either data or file must be provided, but not both.
Members
data: string (optional)
the associated with the secret from
file: string (optional)
the filename to load the data associated with the secret from
The members of SecretCommonProperties
Since
2.6
SecretKeyringProperties (Object)
Properties for secret_keyring objects.
Members
serial: int
serial number that identifies a key to get from the kernel
The members of SecretCommonProperties
Since
5.1
TlsCredsProperties (Object)
Properties for objects of classes derived from tls-creds.
Members
verify-peer: boolean (optional)
if true the peer credentials will be verified once the handshake
is completed. This is a no-op for anonymous credentials. (de-
fault: true)
dir: string (optional)
the path of the directory that contains the credential files
endpoint: QCryptoTLSCredsEndpoint (optional)
whether the QEMU network backend that uses the credentials will
be acting as a client or as a server (default: client)
priority: string (optional)
a gnutls priority string as described at
https://gnutls.org/manual/html_node/Priority-Strings.html
Since
2.5
TlsCredsAnonProperties (Object)
Properties for tls-creds-anon objects.
Members
loaded: boolean (optional)
if true, the credentials are loaded immediately when applying
this option and will ignore options that are processed later.
Don't use; only provided for compatibility. (default: false)
The members of TlsCredsProperties
Features
deprecated
Member loaded is deprecated. Setting true doesn't make sense,
and false is already the default.
Since
2.5
TlsCredsPskProperties (Object)
Properties for tls-creds-psk objects.
Members
loaded: boolean (optional)
if true, the credentials are loaded immediately when applying
this option and will ignore options that are processed later.
Don't use; only provided for compatibility. (default: false)
username: string (optional)
the username which will be sent to the server. For clients
only. If absent, "qemu" is sent and the property will read back
as an empty string.
The members of TlsCredsProperties
Features
deprecated
Member loaded is deprecated. Setting true doesn't make sense,
and false is already the default.
Since
3.0
TlsCredsX509Properties (Object)
Properties for tls-creds-x509 objects.
Members
loaded: boolean (optional)
if true, the credentials are loaded immediately when applying
this option and will ignore options that are processed later.
Don't use; only provided for compatibility. (default: false)
sanity-check: boolean (optional)
if true, perform some sanity checks before using the credentials
(default: true)
passwordid: string (optional)
For the server-key.pem and client-key.pem files which contain
sensitive private keys, it is possible to use an encrypted ver-
sion by providing the passwordid parameter. This provides the
ID of a previously created secret object containing the password
for decryption.
The members of TlsCredsProperties
Features
deprecated
Member loaded is deprecated. Setting true doesn't make sense,
and false is already the default.
Since
2.5
QCryptoAkCipherAlgorithm (Enum)
The supported algorithms for asymmetric encryption ciphers
Values
rsa RSA algorithm
Since
7.1
QCryptoAkCipherKeyType (Enum)
The type of asymmetric keys.
Values
public Not documented
private
Not documented
Since
7.1
QCryptoRSAPaddingAlgorithm (Enum)
The padding algorithm for RSA.
Values
raw no padding used
pkcs1 pkcs1#v1.5
Since
7.1
QCryptoAkCipherOptionsRSA (Object)
Specific parameters for RSA algorithm.
Members
hash-alg: QCryptoHashAlgorithm
QCryptoHashAlgorithm
padding-alg: QCryptoRSAPaddingAlgorithm
QCryptoRSAPaddingAlgorithm
Since
7.1
QCryptoAkCipherOptions (Object)
The options that are available for all asymmetric key algorithms when
creating a new QCryptoAkCipher.
Members
alg: QCryptoAkCipherAlgorithm
Not documented
The members of QCryptoAkCipherOptionsRSA when alg is "rsa"
Since
7.1
BLOCK DEVICES
Block core (VM unrelated)
Background jobs
JobType (Enum)
Type of a background job.
Values
commit block commit job type, see "block-commit"
stream block stream job type, see "block-stream"
mirror drive mirror job type, see "drive-mirror"
backup drive backup job type, see "drive-backup"
create image creation job type, see "blockdev-create" (since 3.0)
amend image options amend job type, see "x-blockdev-amend" (since 5.1)
snapshot-load
snapshot load job type, see "snapshot-load" (since 6.0)
snapshot-save
snapshot save job type, see "snapshot-save" (since 6.0)
snapshot-delete
snapshot delete job type, see "snapshot-delete" (since 6.0)
Since
1.7
JobStatus (Enum)
Indicates the present state of a given job in its lifetime.
Values
undefined
Erroneous, default state. Should not ever be visible.
created
The job has been created, but not yet started.
running
The job is currently running.
paused The job is running, but paused. The pause may be requested by
either the QMP user or by internal processes.
ready The job is running, but is ready for the user to signal comple-
tion. This is used for long-running jobs like mirror that are
designed to run indefinitely.
standby
The job is ready, but paused. This is nearly identical to
paused. The job may return to ready or otherwise be canceled.
waiting
The job is waiting for other jobs in the transaction to converge
to the waiting state. This status will likely not be visible for
the last job in a transaction.
pending
The job has finished its work, but has finalization steps that
it needs to make prior to completing. These changes will require
manual intervention via job-finalize if auto-finalize was set to
false. These pending changes may still fail.
aborting
The job is in the process of being aborted, and will finish with
an error. The job will afterwards report that it is concluded.
This status may not be visible to the management process.
concluded
The job has finished all work. If auto-dismiss was set to false,
the job will remain in the query list until it is dismissed via
job-dismiss.
null The job is in the process of being dismantled. This state should
not ever be visible externally.
Since
2.12
JobVerb (Enum)
Represents command verbs that can be applied to a job.
Values
cancel see job-cancel
pause see job-pause
resume see job-resume
set-speed
see block-job-set-speed
complete
see job-complete
dismiss
see job-dismiss
finalize
see job-finalize
Since
2.12
JOB_STATUS_CHANGE (Event)
Emitted when a job transitions to a different status.
Arguments
id: string
The job identifier
status: JobStatus
The new job status
Since
3.0
job-pause (Command)
Pause an active job.
This command returns immediately after marking the active job for paus-
ing. Pausing an already paused job is an error.
The job will pause as soon as possible, which means transitioning into
the PAUSED state if it was RUNNING, or into STANDBY if it was READY.
The corresponding JOB_STATUS_CHANGE event will be emitted.
Cancelling a paused job automatically resumes it.
Arguments
id: string
The job identifier.
Since
3.0
job-resume (Command)
Resume a paused job.
This command returns immediately after resuming a paused job. Resuming
an already running job is an error.
id : The job identifier.
Arguments
id: string
Not documented
Since
3.0
job-cancel (Command)
Instruct an active background job to cancel at the next opportunity.
This command returns immediately after marking the active job for can-
cellation.
The job will cancel as soon as possible and then emit a JOB_STA-
TUS_CHANGE event. Usually, the status will change to ABORTING, but it
is possible that a job successfully completes (e.g. because it was al-
most done and there was no opportunity to cancel earlier than complet-
ing the job) and transitions to PENDING instead.
Arguments
id: string
The job identifier.
Since
3.0
job-complete (Command)
Manually trigger completion of an active job in the READY state.
Arguments
id: string
The job identifier.
Since
3.0
job-dismiss (Command)
Deletes a job that is in the CONCLUDED state. This command only needs
to be run explicitly for jobs that don't have automatic dismiss en-
abled.
This command will refuse to operate on any job that has not yet reached
its terminal state, JOB_STATUS_CONCLUDED. For jobs that make use of
JOB_READY event, job-cancel or job-complete will still need to be used
as appropriate.
Arguments
id: string
The job identifier.
Since
3.0
job-finalize (Command)
Instructs all jobs in a transaction (or a single job if it is not part
of any transaction) to finalize any graph changes and do any necessary
cleanup. This command requires that all involved jobs are in the PEND-
ING state.
For jobs in a transaction, instructing one job to finalize will force
ALL jobs in the transaction to finalize, so it is only necessary to in-
struct a single member job to finalize.
Arguments
id: string
The identifier of any job in the transaction, or of a job that
is not part of any transaction.
Since
3.0
JobInfo (Object)
Information about a job.
Members
id: string
The job identifier
type: JobType
The kind of job that is being performed
status: JobStatus
Current job state/status
current-progress: int
Progress made until now. The unit is arbitrary and the value can
only meaningfully be used for the ratio of current-progress to
total-progress. The value is monotonically increasing.
total-progress: int
Estimated current-progress value at the completion of the job.
This value can arbitrarily change while the job is running, in
both directions.
error: string (optional)
If this field is present, the job failed; if it is still missing
in the CONCLUDED state, this indicates successful completion.
The value is a human-readable error message to describe the rea-
son for the job failure. It should not be parsed by applica-
tions.
Since
3.0
query-jobs (Command)
Return information about jobs.
Returns
a list with a JobInfo for each active job
Since
3.0
SnapshotInfo (Object)
Members
id: string
unique snapshot id
name: string
user chosen name
vm-state-size: int
size of the VM state
date-sec: int
UTC date of the snapshot in seconds
date-nsec: int
fractional part in nano seconds to be used with date-sec
vm-clock-sec: int
VM clock relative to boot in seconds
vm-clock-nsec: int
fractional part in nano seconds to be used with vm-clock-sec
icount: int (optional)
Current instruction count. Appears when execution record/replay
is enabled. Used for "time-traveling" to match the moment in the
recorded execution with the snapshots. This counter may be ob-
tained through query-replay command (since 5.2)
Since
1.3
ImageInfoSpecificQCow2EncryptionBase (Object)
Members
format: BlockdevQcow2EncryptionFormat
The encryption format
Since
2.10
ImageInfoSpecificQCow2Encryption (Object)
Members
The members of ImageInfoSpecificQCow2EncryptionBase
The members of QCryptoBlockInfoLUKS when format is "luks"
Since
2.10
ImageInfoSpecificQCow2 (Object)
Members
compat: string
compatibility level
data-file: string (optional)
the filename of the external data file that is stored in the im-
age and used as a default for opening the image (since: 4.0)
data-file-raw: boolean (optional)
True if the external data file must stay valid as a standalone
(read-only) raw image without looking at qcow2 metadata (since:
4.0)
extended-l2: boolean (optional)
true if the image has extended L2 entries; only valid for compat
>= 1.1 (since 5.2)
lazy-refcounts: boolean (optional)
on or off; only valid for compat >= 1.1
corrupt: boolean (optional)
true if the image has been marked corrupt; only valid for compat
>= 1.1 (since 2.2)
refcount-bits: int
width of a refcount entry in bits (since 2.3)
encrypt: ImageInfoSpecificQCow2Encryption (optional)
details about encryption parameters; only set if image is en-
crypted (since 2.10)
bitmaps: array of Qcow2BitmapInfo (optional)
A list of qcow2 bitmap details (since 4.0)
compression-type: Qcow2CompressionType
the image cluster compression method (since 5.1)
Since
1.7
ImageInfoSpecificVmdk (Object)
Members
create-type: string
The create type of VMDK image
cid: int
Content id of image
parent-cid: int
Parent VMDK image's cid
extents: array of ImageInfo
List of extent files
Since
1.7
ImageInfoSpecificRbd (Object)
Members
encryption-format: RbdImageEncryptionFormat (optional)
Image encryption format
Since
6.1
ImageInfoSpecificKind (Enum)
Values
luks Since 2.7
rbd Since 6.1
qcow2 Not documented
vmdk Not documented
Since
1.7
ImageInfoSpecificQCow2Wrapper (Object)
Members
data: ImageInfoSpecificQCow2
Not documented
Since
1.7
ImageInfoSpecificVmdkWrapper (Object)
Members
data: ImageInfoSpecificVmdk
Not documented
Since
6.1
ImageInfoSpecificLUKSWrapper (Object)
Members
data: QCryptoBlockInfoLUKS
Not documented
Since
2.7
ImageInfoSpecificRbdWrapper (Object)
Members
data: ImageInfoSpecificRbd
Not documented
Since
6.1
ImageInfoSpecific (Object)
A discriminated record of image format specific information structures.
Members
type: ImageInfoSpecificKind
Not documented
The members of ImageInfoSpecificQCow2Wrapper when type is "qcow2"
The members of ImageInfoSpecificVmdkWrapper when type is "vmdk"
The members of ImageInfoSpecificLUKSWrapper when type is "luks"
The members of ImageInfoSpecificRbdWrapper when type is "rbd"
Since
1.7
ImageInfo (Object)
Information about a QEMU image file
Members
filename: string
name of the image file
format: string
format of the image file
virtual-size: int
maximum capacity in bytes of the image
actual-size: int (optional)
actual size on disk in bytes of the image
dirty-flag: boolean (optional)
true if image is not cleanly closed
cluster-size: int (optional)
size of a cluster in bytes
encrypted: boolean (optional)
true if the image is encrypted
compressed: boolean (optional)
true if the image is compressed (Since 1.7)
backing-filename: string (optional)
name of the backing file
full-backing-filename: string (optional)
full path of the backing file
backing-filename-format: string (optional)
the format of the backing file
snapshots: array of SnapshotInfo (optional)
list of VM snapshots
backing-image: ImageInfo (optional)
info of the backing image (since 1.6)
format-specific: ImageInfoSpecific (optional)
structure supplying additional format-specific information
(since 1.7)
Since
1.3
ImageCheck (Object)
Information about a QEMU image file check
Members
filename: string
name of the image file checked
format: string
format of the image file checked
check-errors: int
number of unexpected errors occurred during check
image-end-offset: int (optional)
offset (in bytes) where the image ends, this field is present if
the driver for the image format supports it
corruptions: int (optional)
number of corruptions found during the check if any
leaks: int (optional)
number of leaks found during the check if any
corruptions-fixed: int (optional)
number of corruptions fixed during the check if any
leaks-fixed: int (optional)
number of leaks fixed during the check if any
total-clusters: int (optional)
total number of clusters, this field is present if the driver
for the image format supports it
allocated-clusters: int (optional)
total number of allocated clusters, this field is present if the
driver for the image format supports it
fragmented-clusters: int (optional)
total number of fragmented clusters, this field is present if
the driver for the image format supports it
compressed-clusters: int (optional)
total number of compressed clusters, this field is present if
the driver for the image format supports it
Since
1.4
MapEntry (Object)
Mapping information from a virtual block range to a host file range
Members
start: int
virtual (guest) offset of the first byte described by this entry
length: int
the number of bytes of the mapped virtual range
data: boolean
reading the image will actually read data from a file (in par-
ticular, if offset is present this means that the sectors are
not simply preallocated, but contain actual data in raw format)
zero: boolean
whether the virtual blocks read as zeroes
depth: int
number of layers (0 = top image, 1 = top image's backing file,
..., n - 1 = bottom image (where n is the number of images in
the chain)) before reaching one for which the range is allocated
present: boolean
true if this layer provides the data, false if adding a backing
layer could impact this region (since 6.1)
offset: int (optional)
if present, the image file stores the data for this range in raw
format at the given (host) offset
filename: string (optional)
filename that is referred to by offset
Since
2.6
BlockdevCacheInfo (Object)
Cache mode information for a block device
Members
writeback: boolean
true if writeback mode is enabled
direct: boolean
true if the host page cache is bypassed (O_DIRECT)
no-flush: boolean
true if flush requests are ignored for the device
Since
2.3
BlockDeviceInfo (Object)
Information about the backing device for a block device.
Members
file: string
the filename of the backing device
node-name: string (optional)
the name of the block driver node (Since 2.0)
ro: boolean
true if the backing device was open read-only
drv: string
the name of the block format used to open the backing device. As
of 0.14 this can be: 'blkdebug', 'bochs', 'cloop', 'cow', 'dmg',
'file', 'file', 'ftp', 'ftps', 'host_cdrom', 'host_device',
'http', 'https', 'luks', 'nbd', 'parallels', 'qcow', 'qcow2',
'raw', 'vdi', 'vmdk', 'vpc', 'vvfat' 2.2: 'archipelago' added,
'cow' dropped 2.3: 'host_floppy' deprecated 2.5: 'host_floppy'
dropped 2.6: 'luks' added 2.8: 'replication' added, 'tftp'
dropped 2.9: 'archipelago' dropped
backing_file: string (optional)
the name of the backing file (for copy-on-write)
backing_file_depth: int
number of files in the backing file chain (since: 1.2)
encrypted: boolean
true if the backing device is encrypted
detect_zeroes: BlockdevDetectZeroesOptions
detect and optimize zero writes (Since 2.1)
bps: int
total throughput limit in bytes per second is specified
bps_rd: int
read throughput limit in bytes per second is specified
bps_wr: int
write throughput limit in bytes per second is specified
iops: int
total I/O operations per second is specified
iops_rd: int
read I/O operations per second is specified
iops_wr: int
write I/O operations per second is specified
image: ImageInfo
the info of image used (since: 1.6)
bps_max: int (optional)
total throughput limit during bursts,
in bytes (Since 1.7)
bps_rd_max: int (optional)
read throughput limit during bursts,
in bytes (Since 1.7)
bps_wr_max: int (optional)
write throughput limit during bursts,
in bytes (Since 1.7)
iops_max: int (optional)
total I/O operations per second during bursts,
in bytes (Since 1.7)
iops_rd_max: int (optional)
read I/O operations per second during bursts,
in bytes (Since 1.7)
iops_wr_max: int (optional)
write I/O operations per second during bursts,
in bytes (Since 1.7)
bps_max_length: int (optional)
maximum length of the bps_max burst
period, in seconds. (Since 2.6)
bps_rd_max_length: int (optional)
maximum length of the bps_rd_max
burst period, in seconds. (Since 2.6)
bps_wr_max_length: int (optional)
maximum length of the bps_wr_max
burst period, in seconds. (Since 2.6)
iops_max_length: int (optional)
maximum length of the iops burst
period, in seconds. (Since 2.6)
iops_rd_max_length: int (optional)
maximum length of the iops_rd_max
burst period, in seconds. (Since 2.6)
iops_wr_max_length: int (optional)
maximum length of the iops_wr_max
burst period, in seconds. (Since 2.6)
iops_size: int (optional)
an I/O size in bytes (Since 1.7)
group: string (optional)
throttle group name (Since 2.4)
cache: BlockdevCacheInfo
the cache mode used for the block device (since: 2.3)
write_threshold: int
configured write threshold for the device. 0 if disabled.
(Since 2.3)
dirty-bitmaps: array of BlockDirtyInfo (optional)
dirty bitmaps information (only present if node has one or more
dirty bitmaps) (Since 4.2)
Since
0.14
BlockDeviceIoStatus (Enum)
An enumeration of block device I/O status.
Values
ok The last I/O operation has succeeded
failed The last I/O operation has failed
nospace
The last I/O operation has failed due to a no-space condition
Since
1.0
BlockDirtyInfo (Object)
Block dirty bitmap information.
Members
name: string (optional)
the name of the dirty bitmap (Since 2.4)
count: int
number of dirty bytes according to the dirty bitmap
granularity: int
granularity of the dirty bitmap in bytes (since 1.4)
recording: boolean
true if the bitmap is recording new writes from the guest. Re-
places active and disabled statuses. (since 4.0)
busy: boolean
true if the bitmap is in-use by some operation (NBD or jobs) and
cannot be modified via QMP or used by another operation. Re-
places locked and frozen statuses. (since 4.0)
persistent: boolean
true if the bitmap was stored on disk, is scheduled to be stored
on disk, or both. (since 4.0)
inconsistent: boolean (optional)
true if this is a persistent bitmap that was improperly stored.
Implies persistent to be true; recording and busy to be false.
This bitmap cannot be used. To remove it, use block-dirty-bit-
map-remove. (Since 4.0)
Since
1.3
Qcow2BitmapInfoFlags (Enum)
An enumeration of flags that a bitmap can report to the user.
Values
in-use This flag is set by any process actively modifying the qcow2
file, and cleared when the updated bitmap is flushed to the
qcow2 image. The presence of this flag in an offline image
means that the bitmap was not saved correctly after its last us-
age, and may contain inconsistent data.
auto The bitmap must reflect all changes of the virtual disk by any
application that would write to this qcow2 file.
Since
4.0
Qcow2BitmapInfo (Object)
Qcow2 bitmap information.
Members
name: string
the name of the bitmap
granularity: int
granularity of the bitmap in bytes
flags: array of Qcow2BitmapInfoFlags
flags of the bitmap
Since
4.0
BlockLatencyHistogramInfo (Object)
Block latency histogram.
Members
boundaries: array of int
list of interval boundary values in nanoseconds, all greater
than zero and in ascending order. For example, the list [10,
50, 100] produces the following histogram intervals: [0, 10),
[10, 50), [50, 100), [100, +inf).
bins: array of int
list of io request counts corresponding to histogram intervals.
len(bins) = len(boundaries) + 1 For the example above, bins may
be something like [3, 1, 5, 2], and corresponding histogram
looks like:
5| *
4| *
3| * *
2| * * *
1| * * * *
+------------------
10 50 100
Since
4.0
BlockInfo (Object)
Block device information. This structure describes a virtual device
and the backing device associated with it.
Members
device: string
The device name associated with the virtual device.
qdev: string (optional)
The qdev ID, or if no ID is assigned, the QOM path of the block
device. (since 2.10)
type: string
This field is returned only for compatibility reasons, it should
not be used (always returns 'unknown')
removable: boolean
True if the device supports removable media.
locked: boolean
True if the guest has locked this device from having its media
removed
tray_open: boolean (optional)
True if the device's tray is open (only present if it has a
tray)
io-status: BlockDeviceIoStatus (optional)
BlockDeviceIoStatus. Only present if the device supports it and
the VM is configured to stop on errors (supported device models:
virtio-blk, IDE, SCSI except scsi-generic)
inserted: BlockDeviceInfo (optional)
BlockDeviceInfo describing the device if media is present
Since
0.14
BlockMeasureInfo (Object)
Image file size calculation information. This structure describes the
size requirements for creating a new image file.
The size requirements depend on the new image file format. File size
always equals virtual disk size for the 'raw' format, even for sparse
POSIX files. Compact formats such as 'qcow2' represent unallocated and
zero regions efficiently so file size may be smaller than virtual disk
size.
The values are upper bounds that are guaranteed to fit the new image
file. Subsequent modification, such as internal snapshot or further
bitmap creation, may require additional space and is not covered here.
Members
required: int
Size required for a new image file, in bytes, when copying just
allocated guest-visible contents.
fully-allocated: int
Image file size, in bytes, once data has been written to all
sectors, when copying just guest-visible contents.
bitmaps: int (optional)
Additional size required if all the top-level bitmap metadata in
the source image were to be copied to the destination, present
only when source and destination both support persistent bit-
maps. (since 5.1)
Since
2.10
query-block (Command)
Get a list of BlockInfo for all virtual block devices.
Returns
a list of BlockInfo describing each virtual block device. Filter nodes
that were created implicitly are skipped over.
Since
0.14
Example
-> { "execute": "query-block" }
<- {
"return":[
{
"io-status": "ok",
"device":"ide0-hd0",
"locked":false,
"removable":false,
"inserted":{
"ro":false,
"drv":"qcow2",
"encrypted":false,
"file":"disks/test.qcow2",
"backing_file_depth":1,
"bps":1000000,
"bps_rd":0,
"bps_wr":0,
"iops":1000000,
"iops_rd":0,
"iops_wr":0,
"bps_max": 8000000,
"bps_rd_max": 0,
"bps_wr_max": 0,
"iops_max": 0,
"iops_rd_max": 0,
"iops_wr_max": 0,
"iops_size": 0,
"detect_zeroes": "on",
"write_threshold": 0,
"image":{
"filename":"disks/test.qcow2",
"format":"qcow2",
"virtual-size":2048000,
"backing_file":"base.qcow2",
"full-backing-filename":"disks/base.qcow2",
"backing-filename-format":"qcow2",
"snapshots":[
{
"id": "1",
"name": "snapshot1",
"vm-state-size": 0,
"date-sec": 10000200,
"date-nsec": 12,
"vm-clock-sec": 206,
"vm-clock-nsec": 30
}
],
"backing-image":{
"filename":"disks/base.qcow2",
"format":"qcow2",
"virtual-size":2048000
}
}
},
"qdev": "ide_disk",
"type":"unknown"
},
{
"io-status": "ok",
"device":"ide1-cd0",
"locked":false,
"removable":true,
"qdev": "/machine/unattached/device[23]",
"tray_open": false,
"type":"unknown"
},
{
"device":"floppy0",
"locked":false,
"removable":true,
"qdev": "/machine/unattached/device[20]",
"type":"unknown"
},
{
"device":"sd0",
"locked":false,
"removable":true,
"type":"unknown"
}
]
}
BlockDeviceTimedStats (Object)
Statistics of a block device during a given interval of time.
Members
interval_length: int
Interval used for calculating the statistics, in seconds.
min_rd_latency_ns: int
Minimum latency of read operations in the defined interval, in
nanoseconds.
min_wr_latency_ns: int
Minimum latency of write operations in the defined interval, in
nanoseconds.
min_flush_latency_ns: int
Minimum latency of flush operations in the defined interval, in
nanoseconds.
max_rd_latency_ns: int
Maximum latency of read operations in the defined interval, in
nanoseconds.
max_wr_latency_ns: int
Maximum latency of write operations in the defined interval, in
nanoseconds.
max_flush_latency_ns: int
Maximum latency of flush operations in the defined interval, in
nanoseconds.
avg_rd_latency_ns: int
Average latency of read operations in the defined interval, in
nanoseconds.
avg_wr_latency_ns: int
Average latency of write operations in the defined interval, in
nanoseconds.
avg_flush_latency_ns: int
Average latency of flush operations in the defined interval, in
nanoseconds.
avg_rd_queue_depth: number
Average number of pending read operations in the defined inter-
val.
avg_wr_queue_depth: number
Average number of pending write operations in the defined inter-
val.
Since
2.5
BlockDeviceStats (Object)
Statistics of a virtual block device or a block backing device.
Members
rd_bytes: int
The number of bytes read by the device.
wr_bytes: int
The number of bytes written by the device.
unmap_bytes: int
The number of bytes unmapped by the device (Since 4.2)
rd_operations: int
The number of read operations performed by the device.
wr_operations: int
The number of write operations performed by the device.
flush_operations: int
The number of cache flush operations performed by the device
(since 0.15)
unmap_operations: int
The number of unmap operations performed by the device (Since
4.2)
rd_total_time_ns: int
Total time spent on reads in nanoseconds (since 0.15).
wr_total_time_ns: int
Total time spent on writes in nanoseconds (since 0.15).
flush_total_time_ns: int
Total time spent on cache flushes in nanoseconds (since 0.15).
unmap_total_time_ns: int
Total time spent on unmap operations in nanoseconds (Since 4.2)
wr_highest_offset: int
The offset after the greatest byte written to the device. The
intended use of this information is for growable sparse files
(like qcow2) that are used on top of a physical device.
rd_merged: int
Number of read requests that have been merged into another re-
quest (Since 2.3).
wr_merged: int
Number of write requests that have been merged into another re-
quest (Since 2.3).
unmap_merged: int
Number of unmap requests that have been merged into another re-
quest (Since 4.2)
idle_time_ns: int (optional)
Time since the last I/O operation, in nanoseconds. If the field
is absent it means that there haven't been any operations yet
(Since 2.5).
failed_rd_operations: int
The number of failed read operations performed by the device
(Since 2.5)
failed_wr_operations: int
The number of failed write operations performed by the device
(Since 2.5)
failed_flush_operations: int
The number of failed flush operations performed by the device
(Since 2.5)
failed_unmap_operations: int
The number of failed unmap operations performed by the device
(Since 4.2)
invalid_rd_operations: int
The number of invalid read operations
performed by the device (Since 2.5)
invalid_wr_operations: int
The number of invalid write operations performed by the device
(Since 2.5)
invalid_flush_operations: int
The number of invalid flush operations performed by the device
(Since 2.5)
invalid_unmap_operations: int
The number of invalid unmap operations performed by the device
(Since 4.2)
account_invalid: boolean
Whether invalid operations are included in the last access sta-
tistics (Since 2.5)
account_failed: boolean
Whether failed operations are included in the latency and last
access statistics (Since 2.5)
timed_stats: array of BlockDeviceTimedStats
Statistics specific to the set of previously defined intervals
of time (Since 2.5)
rd_latency_histogram: BlockLatencyHistogramInfo (optional)
BlockLatencyHistogramInfo. (Since 4.0)
wr_latency_histogram: BlockLatencyHistogramInfo (optional)
BlockLatencyHistogramInfo. (Since 4.0)
flush_latency_histogram: BlockLatencyHistogramInfo (optional)
BlockLatencyHistogramInfo. (Since 4.0)
Since
0.14
BlockStatsSpecificFile (Object)
File driver statistics
Members
discard-nb-ok: int
The number of successful discard operations performed by the
driver.
discard-nb-failed: int
The number of failed discard operations performed by the driver.
discard-bytes-ok: int
The number of bytes discarded by the driver.
Since
4.2
BlockStatsSpecificNvme (Object)
NVMe driver statistics
Members
completion-errors: int
The number of completion errors.
aligned-accesses: int
The number of aligned accesses performed by the driver.
unaligned-accesses: int
The number of unaligned accesses performed by the driver.
Since
5.2
BlockStatsSpecific (Object)
Block driver specific statistics
Members
driver: BlockdevDriver
Not documented
The members of BlockStatsSpecificFile when driver is "file"
The members of BlockStatsSpecificFile when driver is "host_device" (If:
HAVE_HOST_BLOCK_DEVICE)
The members of BlockStatsSpecificNvme when driver is "nvme"
Since
4.2
BlockStats (Object)
Statistics of a virtual block device or a block backing device.
Members
device: string (optional)
If the stats are for a virtual block device, the name corre-
sponding to the virtual block device.
node-name: string (optional)
The node name of the device. (Since 2.3)
qdev: string (optional)
The qdev ID, or if no ID is assigned, the QOM path of the block
device. (since 3.0)
stats: BlockDeviceStats
A BlockDeviceStats for the device.
driver-specific: BlockStatsSpecific (optional)
Optional driver-specific stats. (Since 4.2)
parent: BlockStats (optional)
This describes the file block device if it has one. Contains
recursively the statistics of the underlying protocol (e.g. the
host file for a qcow2 image). If there is no underlying proto-
col, this field is omitted
backing: BlockStats (optional)
This describes the backing block device if it has one. (Since
2.0)
Since
0.14
query-blockstats (Command)
Query the BlockStats for all virtual block devices.
Arguments
query-nodes: boolean (optional)
If true, the command will query all the block nodes that have a
node name, in a list which will include "parent" information,
but not "backing". If false or omitted, the behavior is as be-
fore - query all the device backends, recursively including
their "parent" and "backing". Filter nodes that were created im-
plicitly are skipped over in this mode. (Since 2.3)
Returns
A list of BlockStats for each virtual block devices.
Since
0.14
Example
-> { "execute": "query-blockstats" }
<- {
"return":[
{
"device":"ide0-hd0",
"parent":{
"stats":{
"wr_highest_offset":3686448128,
"wr_bytes":9786368,
"wr_operations":751,
"rd_bytes":122567168,
"rd_operations":36772
"wr_total_times_ns":313253456
"rd_total_times_ns":3465673657
"flush_total_times_ns":49653
"flush_operations":61,
"rd_merged":0,
"wr_merged":0,
"idle_time_ns":2953431879,
"account_invalid":true,
"account_failed":false
}
},
"stats":{
"wr_highest_offset":2821110784,
"wr_bytes":9786368,
"wr_operations":692,
"rd_bytes":122739200,
"rd_operations":36604
"flush_operations":51,
"wr_total_times_ns":313253456
"rd_total_times_ns":3465673657
"flush_total_times_ns":49653,
"rd_merged":0,
"wr_merged":0,
"idle_time_ns":2953431879,
"account_invalid":true,
"account_failed":false
},
"qdev": "/machine/unattached/device[23]"
},
{
"device":"ide1-cd0",
"stats":{
"wr_highest_offset":0,
"wr_bytes":0,
"wr_operations":0,
"rd_bytes":0,
"rd_operations":0
"flush_operations":0,
"wr_total_times_ns":0
"rd_total_times_ns":0
"flush_total_times_ns":0,
"rd_merged":0,
"wr_merged":0,
"account_invalid":false,
"account_failed":false
},
"qdev": "/machine/unattached/device[24]"
},
{
"device":"floppy0",
"stats":{
"wr_highest_offset":0,
"wr_bytes":0,
"wr_operations":0,
"rd_bytes":0,
"rd_operations":0
"flush_operations":0,
"wr_total_times_ns":0
"rd_total_times_ns":0
"flush_total_times_ns":0,
"rd_merged":0,
"wr_merged":0,
"account_invalid":false,
"account_failed":false
},
"qdev": "/machine/unattached/device[16]"
},
{
"device":"sd0",
"stats":{
"wr_highest_offset":0,
"wr_bytes":0,
"wr_operations":0,
"rd_bytes":0,
"rd_operations":0
"flush_operations":0,
"wr_total_times_ns":0
"rd_total_times_ns":0
"flush_total_times_ns":0,
"rd_merged":0,
"wr_merged":0,
"account_invalid":false,
"account_failed":false
}
}
]
}
BlockdevOnError (Enum)
An enumeration of possible behaviors for errors on I/O operations. The
exact meaning depends on whether the I/O was initiated by a guest or by
a block job
Values
report for guest operations, report the error to the guest; for jobs,
cancel the job
ignore ignore the error, only report a QMP event (BLOCK_IO_ERROR or
BLOCK_JOB_ERROR). The backup, mirror and commit block jobs retry
the failing request later and may still complete successfully.
The stream block job continues to stream and will complete with
an error.
enospc same as stop on ENOSPC, same as report otherwise.
stop for guest operations, stop the virtual machine; for jobs, pause
the job
auto inherit the error handling policy of the backend (since: 2.7)
Since
1.3
MirrorSyncMode (Enum)
An enumeration of possible behaviors for the initial synchronization
phase of storage mirroring.
Values
top copies data in the topmost image to the destination
full copies data from all images to the destination
none only copy data written from now on
incremental
only copy data described by the dirty bitmap. (since: 2.4)
bitmap only copy data described by the dirty bitmap. (since: 4.2) Be-
havior on completion is determined by the BitmapSyncMode.
Since
1.3
BitmapSyncMode (Enum)
An enumeration of possible behaviors for the synchronization of a bit-
map when used for data copy operations.
Values
on-success
The bitmap is only synced when the operation is successful.
This is the behavior always used for 'INCREMENTAL' backups.
never The bitmap is never synchronized with the operation, and is
treated solely as a read-only manifest of blocks to copy.
always The bitmap is always synchronized with the operation, regardless
of whether or not the operation was successful.
Since
4.2
MirrorCopyMode (Enum)
An enumeration whose values tell the mirror block job when to trigger
writes to the target.
Values
background
copy data in background only.
write-blocking
when data is written to the source, write it (synchronously) to
the target as well. In addition, data is copied in background
just like in background mode.
Since
3.0
BlockJobInfo (Object)
Information about a long-running block device operation.
Members
type: string
the job type ('stream' for image streaming)
device: string
The job identifier. Originally the device name but other values
are allowed since QEMU 2.7
len: int
Estimated offset value at the completion of the job. This value
can arbitrarily change while the job is running, in both direc-
tions.
offset: int
Progress made until now. The unit is arbitrary and the value can
only meaningfully be used for the ratio of offset to len. The
value is monotonically increasing.
busy: boolean
false if the job is known to be in a quiescent state, with no
pending I/O. Since 1.3.
paused: boolean
whether the job is paused or, if busy is true, will pause itself
as soon as possible. Since 1.3.
speed: int
the rate limit, bytes per second
io-status: BlockDeviceIoStatus
the status of the job (since 1.3)
ready: boolean
true if the job may be completed (since 2.2)
status: JobStatus
Current job state/status (since 2.12)
auto-finalize: boolean
Job will finalize itself when PENDING, moving to the CONCLUDED
state. (since 2.12)
auto-dismiss: boolean
Job will dismiss itself when CONCLUDED, moving to the NULL state
and disappearing from the query list. (since 2.12)
error: string (optional)
Error information if the job did not complete successfully. Not
set if the job completed successfully. (since 2.12.1)
Since
1.1
query-block-jobs (Command)
Return information about long-running block device operations.
Returns
a list of BlockJobInfo for each active block job
Since
1.1
block_resize (Command)
Resize a block image while a guest is running.
Either device or node-name must be set but not both.
Arguments
device: string (optional)
the name of the device to get the image resized
node-name: string (optional)
graph node name to get the image resized (Since 2.0)
size: int
new image size in bytes
Returns
• nothing on success
• If device is not a valid block device, DeviceNotFound
Since
0.14
Example
-> { "execute": "block_resize",
"arguments": { "device": "scratch", "size": 1073741824 } }
<- { "return": {} }
NewImageMode (Enum)
An enumeration that tells QEMU how to set the backing file path in a
new image file.
Values
existing
QEMU should look for an existing image file.
absolute-paths
QEMU should create a new image with absolute paths for the back-
ing file. If there is no backing file available, the new image
will not be backed either.
Since
1.1
BlockdevSnapshotSync (Object)
Either device or node-name must be set but not both.
Members
device: string (optional)
the name of the device to take a snapshot of.
node-name: string (optional)
graph node name to generate the snapshot from (Since 2.0)
snapshot-file: string
the target of the new overlay image. If the file exists, or if
it is a device, the overlay will be created in the existing
file/device. Otherwise, a new file will be created.
snapshot-node-name: string (optional)
the graph node name of the new image (Since 2.0)
format: string (optional)
the format of the overlay image, default is 'qcow2'.
mode: NewImageMode (optional)
whether and how QEMU should create a new image, default is 'ab-
solute-paths'.
BlockdevSnapshot (Object)
Members
node: string
device or node name that will have a snapshot taken.
overlay: string
reference to the existing block device that will become the
overlay of node, as part of taking the snapshot. It must not
have a current backing file (this can be achieved by passing
"backing": null to blockdev-add).
Since
2.5
BackupPerf (Object)
Optional parameters for backup. These parameters don't affect function-
ality, but may significantly affect performance.
Members
use-copy-range: boolean (optional)
Use copy offloading. Default false.
max-workers: int (optional)
Maximum number of parallel requests for the sustained background
copying process. Doesn't influence copy-before-write operations.
Default 64.
max-chunk: int (optional)
Maximum request length for the sustained background copying
process. Doesn't influence copy-before-write operations. 0
means unlimited. If max-chunk is non-zero then it should not be
less than job cluster size which is calculated as maximum of
target image cluster size and 64k. Default 0.
Since
6.0
BackupCommon (Object)
Members
job-id: string (optional)
identifier for the newly-created block job. If omitted, the de-
vice name will be used. (Since 2.7)
device: string
the device name or node-name of a root node which should be
copied.
sync: MirrorSyncMode
what parts of the disk image should be copied to the destination
(all the disk, only the sectors allocated in the topmost image,
from a dirty bitmap, or only new I/O).
speed: int (optional)
the maximum speed, in bytes per second. The default is 0, for
unlimited.
bitmap: string (optional)
The name of a dirty bitmap to use. Must be present if sync is
"bitmap" or "incremental". Can be present if sync is "full" or
"top". Must not be present otherwise. (Since 2.4
(drive-backup), 3.1 (blockdev-backup))
bitmap-mode: BitmapSyncMode (optional)
Specifies the type of data the bitmap should contain after the
operation concludes. Must be present if a bitmap was provided,
Must NOT be present otherwise. (Since 4.2)
compress: boolean (optional)
true to compress data, if the target format supports it. (de-
fault: false) (since 2.8)
on-source-error: BlockdevOnError (optional)
the action to take on an error on the source, default 'report'.
'stop' and 'enospc' can only be used if the block device sup-
ports io-status (see BlockInfo).
on-target-error: BlockdevOnError (optional)
the action to take on an error on the target, default 'report'
(no limitations, since this applies to a different block device
than device).
auto-finalize: boolean (optional)
When false, this job will wait in a PENDING state after it has
finished its work, waiting for block-job-finalize before making
any block graph changes. When true, this job will automatically
perform its abort or commit actions. Defaults to true. (Since
2.12)
auto-dismiss: boolean (optional)
When false, this job will wait in a CONCLUDED state after it has
completely ceased all work, and awaits block-job-dismiss. When
true, this job will automatically disappear from the query list
without user intervention. Defaults to true. (Since 2.12)
filter-node-name: string (optional)
the node name that should be assigned to the filter driver that
the backup job inserts into the graph above node specified by
drive. If this option is not given, a node name is autogener-
ated. (Since: 4.2)
x-perf: BackupPerf (optional)
Performance options. (Since 6.0)
Features
unstable
Member x-perf is experimental.
Note
on-source-error and on-target-error only affect background I/O. If an
error occurs during a guest write request, the device's rerror/werror
actions will be used.
Since
4.2
DriveBackup (Object)
Members
target: string
the target of the new image. If the file exists, or if it is a
device, the existing file/device will be used as the new desti-
nation. If it does not exist, a new file will be created.
format: string (optional)
the format of the new destination, default is to probe if mode
is 'existing', else the format of the source
mode: NewImageMode (optional)
whether and how QEMU should create a new image, default is 'ab-
solute-paths'.
The members of BackupCommon
Since
1.6
BlockdevBackup (Object)
Members
target: string
the device name or node-name of the backup target node.
The members of BackupCommon
Since
2.3
blockdev-snapshot-sync (Command)
Takes a synchronous snapshot of a block device.
For the arguments, see the documentation of BlockdevSnapshotSync.
Returns
• nothing on success
• If device is not a valid block device, DeviceNotFound
Since
0.14
Example
-> { "execute": "blockdev-snapshot-sync",
"arguments": { "device": "ide-hd0",
"snapshot-file":
"/some/place/my-image",
"format": "qcow2" } }
<- { "return": {} }
blockdev-snapshot (Command)
Takes a snapshot of a block device.
Take a snapshot, by installing 'node' as the backing image of 'over-
lay'. Additionally, if 'node' is associated with a block device, the
block device changes to using 'overlay' as its new active image.
For the arguments, see the documentation of BlockdevSnapshot.
Features
allow-write-only-overlay
If present, the check whether this operation is safe was relaxed
so that it can be used to change backing file of a destination
of a blockdev-mirror. (since 5.0)
Since
2.5
Example
-> { "execute": "blockdev-add",
"arguments": { "driver": "qcow2",
"node-name": "node1534",
"file": { "driver": "file",
"filename": "hd1.qcow2" },
"backing": null } }
<- { "return": {} }
-> { "execute": "blockdev-snapshot",
"arguments": { "node": "ide-hd0",
"overlay": "node1534" } }
<- { "return": {} }
change-backing-file (Command)
Change the backing file in the image file metadata. This does not
cause QEMU to reopen the image file to reparse the backing filename (it
may, however, perform a reopen to change permissions from r/o -> r/w ->
r/o, if needed). The new backing file string is written into the image
file metadata, and the QEMU internal strings are updated.
Arguments
image-node-name: string
The name of the block driver state node of the image to modify.
The "device" argument is used to verify "image-node-name" is in
the chain described by "device".
device: string
The device name or node-name of the root node that owns im-
age-node-name.
backing-file: string
The string to write as the backing file. This string is not
validated, so care should be taken when specifying the string or
the image chain may not be able to be reopened again.
Returns
• Nothing on success
• If "device" does not exist or cannot be determined, DeviceNotFound
Since
2.1
block-commit (Command)
Live commit of data from overlay image nodes into backing nodes - i.e.,
writes data between 'top' and 'base' into 'base'.
If top == base, that is an error. If top has no overlays on top of it,
or if it is in use by a writer, the job will not be completed by it-
self. The user needs to complete the job with the block-job-complete
command after getting the ready event. (Since 2.0)
If the base image is smaller than top, then the base image will be re-
sized to be the same size as top. If top is smaller than the base im-
age, the base will not be truncated. If you want the base image size
to match the size of the smaller top, you can safely truncate it your-
self once the commit operation successfully completes.
Arguments
job-id: string (optional)
identifier for the newly-created block job. If omitted, the de-
vice name will be used. (Since 2.7)
device: string
the device name or node-name of a root node
base-node: string (optional)
The node name of the backing image to write data into. If not
specified, this is the deepest backing image. (since: 3.1)
base: string (optional)
Same as base-node, except that it is a file name rather than a
node name. This must be the exact filename string that was used
to open the node; other strings, even if addressing the same
file, are not accepted
top-node: string (optional)
The node name of the backing image within the image chain which
contains the topmost data to be committed down. If not speci-
fied, this is the active layer. (since: 3.1)
top: string (optional)
Same as top-node, except that it is a file name rather than a
node name. This must be the exact filename string that was used
to open the node; other strings, even if addressing the same
file, are not accepted
backing-file: string (optional)
The backing file string to write into the overlay image of
'top'. If 'top' does not have an overlay image, or if 'top' is
in use by a writer, specifying a backing file string is an er-
ror.
This filename is not validated. If a pathname string is such
that it cannot be resolved by QEMU, that means that subsequent
QMP or HMP commands must use node-names for the image in ques-
tion, as filename lookup methods will fail.
If not specified, QEMU will automatically determine the backing
file string to use, or error out if there is no obvious choice.
Care should be taken when specifying the string, to specify a
valid filename or protocol. (Since 2.1)
speed: int (optional)
the maximum speed, in bytes per second
on-error: BlockdevOnError (optional)
the action to take on an error. 'ignore' means that the request
should be retried. (default: report; Since: 5.0)
filter-node-name: string (optional)
the node name that should be assigned to the filter driver that
the commit job inserts into the graph above top. If this option
is not given, a node name is autogenerated. (Since: 2.9)
auto-finalize: boolean (optional)
When false, this job will wait in a PENDING state after it has
finished its work, waiting for block-job-finalize before making
any block graph changes. When true, this job will automatically
perform its abort or commit actions. Defaults to true. (Since
3.1)
auto-dismiss: boolean (optional)
When false, this job will wait in a CONCLUDED state after it has
completely ceased all work, and awaits block-job-dismiss. When
true, this job will automatically disappear from the query list
without user intervention. Defaults to true. (Since 3.1)
Features
deprecated
Members base and top are deprecated. Use base-node and top-node
instead.
Returns
• Nothing on success
• If device does not exist, DeviceNotFound
• Any other error returns a GenericError.
Since
1.3
Example
-> { "execute": "block-commit",
"arguments": { "device": "virtio0",
"top": "/tmp/snap1.qcow2" } }
<- { "return": {} }
drive-backup (Command)
Start a point-in-time copy of a block device to a new destination. The
status of ongoing drive-backup operations can be checked with
query-block-jobs where the BlockJobInfo.type field has the value
'backup'. The operation can be stopped before it has completed using
the block-job-cancel command.
Arguments
The members of DriveBackup
Features
deprecated
This command is deprecated. Use blockdev-backup instead.
Returns
• nothing on success
• If device is not a valid block device, GenericError
Since
1.6
Example
-> { "execute": "drive-backup",
"arguments": { "device": "drive0",
"sync": "full",
"target": "backup.img" } }
<- { "return": {} }
blockdev-backup (Command)
Start a point-in-time copy of a block device to a new destination. The
status of ongoing blockdev-backup operations can be checked with
query-block-jobs where the BlockJobInfo.type field has the value
'backup'. The operation can be stopped before it has completed using
the block-job-cancel command.
Arguments
The members of BlockdevBackup
Returns
• nothing on success
• If device is not a valid block device, DeviceNotFound
Since
2.3
Example
-> { "execute": "blockdev-backup",
"arguments": { "device": "src-id",
"sync": "full",
"target": "tgt-id" } }
<- { "return": {} }
query-named-block-nodes (Command)
Get the named block driver list
Arguments
flat: boolean (optional)
Omit the nested data about backing image ("backing-image" key)
if true. Default is false (Since 5.0)
Returns
the list of BlockDeviceInfo
Since
2.0
Example
-> { "execute": "query-named-block-nodes" }
<- { "return": [ { "ro":false,
"drv":"qcow2",
"encrypted":false,
"file":"disks/test.qcow2",
"node-name": "my-node",
"backing_file_depth":1,
"detect_zeroes":"off",
"bps":1000000,
"bps_rd":0,
"bps_wr":0,
"iops":1000000,
"iops_rd":0,
"iops_wr":0,
"bps_max": 8000000,
"bps_rd_max": 0,
"bps_wr_max": 0,
"iops_max": 0,
"iops_rd_max": 0,
"iops_wr_max": 0,
"iops_size": 0,
"write_threshold": 0,
"image":{
"filename":"disks/test.qcow2",
"format":"qcow2",
"virtual-size":2048000,
"backing_file":"base.qcow2",
"full-backing-filename":"disks/base.qcow2",
"backing-filename-format":"qcow2",
"snapshots":[
{
"id": "1",
"name": "snapshot1",
"vm-state-size": 0,
"date-sec": 10000200,
"date-nsec": 12,
"vm-clock-sec": 206,
"vm-clock-nsec": 30
}
],
"backing-image":{
"filename":"disks/base.qcow2",
"format":"qcow2",
"virtual-size":2048000
}
} } ] }
XDbgBlockGraphNodeType (Enum)
Values
block-backend
corresponds to BlockBackend
block-job
corresponds to BlockJob
block-driver
corresponds to BlockDriverState
Since
4.0
XDbgBlockGraphNode (Object)
Members
id: int
Block graph node identifier. This id is generated only for x-de-
bug-query-block-graph and does not relate to any other identi-
fiers in Qemu.
type: XDbgBlockGraphNodeType
Type of graph node. Can be one of block-backend, block-job or
block-driver-state.
name: string
Human readable name of the node. Corresponds to node-name for
block-driver-state nodes; is not guaranteed to be unique in the
whole graph (with block-jobs and block-backends).
Since
4.0
BlockPermission (Enum)
Enum of base block permissions.
Values
consistent-read
A user that has the "permission" of consistent reads is guaran-
teed that their view of the contents of the block device is com-
plete and self-consistent, representing the contents of a disk
at a specific point. For most block devices (including their
backing files) this is true, but the property cannot be main-
tained in a few situations like for intermediate nodes of a com-
mit block job.
write This permission is required to change the visible disk contents.
write-unchanged
This permission (which is weaker than BLK_PERM_WRITE) is both
enough and required for writes to the block node when the caller
promises that the visible disk content doesn't change. As the
BLK_PERM_WRITE permission is strictly stronger, either is suffi-
cient to perform an unchanging write.
resize This permission is required to change the size of a block node.
Since
4.0
XDbgBlockGraphEdge (Object)
Block Graph edge description for x-debug-query-block-graph.
Members
parent: int
parent id
child: int
child id
name: string
name of the relation (examples are 'file' and 'backing')
perm: array of BlockPermission
granted permissions for the parent operating on the child
shared-perm: array of BlockPermission
permissions that can still be granted to other users of the
child while it is still attached to this parent
Since
4.0
XDbgBlockGraph (Object)
Block Graph - list of nodes and list of edges.
Members
nodes: array of XDbgBlockGraphNode
Not documented
edges: array of XDbgBlockGraphEdge
Not documented
Since
4.0
x-debug-query-block-graph (Command)
Get the block graph.
Features
unstable
This command is meant for debugging.
Since
4.0
drive-mirror (Command)
Start mirroring a block device's writes to a new destination. target
specifies the target of the new image. If the file exists, or if it is
a device, it will be used as the new destination for writes. If it does
not exist, a new file will be created. format specifies the format of
the mirror image, default is to probe if mode='existing', else the for-
mat of the source.
Arguments
The members of DriveMirror
Returns
• nothing on success
• If device is not a valid block device, GenericError
Since
1.3
Example
-> { "execute": "drive-mirror",
"arguments": { "device": "ide-hd0",
"target": "/some/place/my-image",
"sync": "full",
"format": "qcow2" } }
<- { "return": {} }
DriveMirror (Object)
A set of parameters describing drive mirror setup.
Members
job-id: string (optional)
identifier for the newly-created block job. If omitted, the de-
vice name will be used. (Since 2.7)
device: string
the device name or node-name of a root node whose writes should
be mirrored.
target: string
the target of the new image. If the file exists, or if it is a
device, the existing file/device will be used as the new desti-
nation. If it does not exist, a new file will be created.
format: string (optional)
the format of the new destination, default is to probe if mode
is 'existing', else the format of the source
node-name: string (optional)
the new block driver state node name in the graph (Since 2.1)
replaces: string (optional)
with sync=full graph node name to be replaced by the new image
when a whole image copy is done. This can be used to repair bro-
ken Quorum files. By default, device is replaced, although im-
plicitly created filters on it are kept. (Since 2.1)
mode: NewImageMode (optional)
whether and how QEMU should create a new image, default is 'ab-
solute-paths'.
speed: int (optional)
the maximum speed, in bytes per second
sync: MirrorSyncMode
what parts of the disk image should be copied to the destination
(all the disk, only the sectors allocated in the topmost image,
or only new I/O).
granularity: int (optional)
granularity of the dirty bitmap, default is 64K if the image
format doesn't have clusters, 4K if the clusters are smaller
than that, else the cluster size. Must be a power of 2 between
512 and 64M (since 1.4).
buf-size: int (optional)
maximum amount of data in flight from source to target (since
1.4).
on-source-error: BlockdevOnError (optional)
the action to take on an error on the source, default 'report'.
'stop' and 'enospc' can only be used if the block device sup-
ports io-status (see BlockInfo).
on-target-error: BlockdevOnError (optional)
the action to take on an error on the target, default 'report'
(no limitations, since this applies to a different block device
than device).
unmap: boolean (optional)
Whether to try to unmap target sectors where source has only
zero. If true, and target unallocated sectors will read as zero,
target image sectors will be unmapped; otherwise, zeroes will be
written. Both will result in identical contents. Default is
true. (Since 2.4)
copy-mode: MirrorCopyMode (optional)
when to copy data to the destination; defaults to 'background'
(Since: 3.0)
auto-finalize: boolean (optional)
When false, this job will wait in a PENDING state after it has
finished its work, waiting for block-job-finalize before making
any block graph changes. When true, this job will automatically
perform its abort or commit actions. Defaults to true. (Since
3.1)
auto-dismiss: boolean (optional)
When false, this job will wait in a CONCLUDED state after it has
completely ceased all work, and awaits block-job-dismiss. When
true, this job will automatically disappear from the query list
without user intervention. Defaults to true. (Since 3.1)
Since
1.3
BlockDirtyBitmap (Object)
Members
node: string
name of device/node which the bitmap is tracking
name: string
name of the dirty bitmap
Since
2.4
BlockDirtyBitmapAdd (Object)
Members
node: string
name of device/node which the bitmap is tracking
name: string
name of the dirty bitmap (must be less than 1024 bytes)
granularity: int (optional)
the bitmap granularity, default is 64k for block-dirty-bit-
map-add
persistent: boolean (optional)
the bitmap is persistent, i.e. it will be saved to the corre-
sponding block device image file on its close. For now only
Qcow2 disks support persistent bitmaps. Default is false for
block-dirty-bitmap-add. (Since: 2.10)
disabled: boolean (optional)
the bitmap is created in the disabled state, which means that it
will not track drive changes. The bitmap may be enabled with
block-dirty-bitmap-enable. Default is false. (Since: 4.0)
Since
2.4
BlockDirtyBitmapOrStr (Alternate)
Members
local: string
name of the bitmap, attached to the same node as target bitmap.
external: BlockDirtyBitmap
bitmap with specified node
Since
4.1
BlockDirtyBitmapMerge (Object)
Members
node: string
name of device/node which the target bitmap is tracking
target: string
name of the destination dirty bitmap
bitmaps: array of BlockDirtyBitmapOrStr
name(s) of the source dirty bitmap(s) at node and/or fully spec-
ified BlockDirtyBitmap elements. The latter are supported since
4.1.
Since
4.0
block-dirty-bitmap-add (Command)
Create a dirty bitmap with a name on the node, and start tracking the
writes.
Returns
• nothing on success
• If node is not a valid block device or node, DeviceNotFound
• If name is already taken, GenericError with an explanation
Since
2.4
Example
-> { "execute": "block-dirty-bitmap-add",
"arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }
block-dirty-bitmap-remove (Command)
Stop write tracking and remove the dirty bitmap that was created with
block-dirty-bitmap-add. If the bitmap is persistent, remove it from its
storage too.
Returns
• nothing on success
• If node is not a valid block device or node, DeviceNotFound
• If name is not found, GenericError with an explanation
• if name is frozen by an operation, GenericError
Since
2.4
Example
-> { "execute": "block-dirty-bitmap-remove",
"arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }
block-dirty-bitmap-clear (Command)
Clear (reset) a dirty bitmap on the device, so that an incremental
backup from this point in time forward will only backup clusters modi-
fied after this clear operation.
Returns
• nothing on success
• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError with an explanation
Since
2.4
Example
-> { "execute": "block-dirty-bitmap-clear",
"arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }
block-dirty-bitmap-enable (Command)
Enables a dirty bitmap so that it will begin tracking disk changes.
Returns
• nothing on success
• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError with an explanation
Since
4.0
Example
-> { "execute": "block-dirty-bitmap-enable",
"arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }
block-dirty-bitmap-disable (Command)
Disables a dirty bitmap so that it will stop tracking disk changes.
Returns
• nothing on success
• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError with an explanation
Since
4.0
Example
-> { "execute": "block-dirty-bitmap-disable",
"arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }
block-dirty-bitmap-merge (Command)
Merge dirty bitmaps listed in bitmaps to the target dirty bitmap.
Dirty bitmaps in bitmaps will be unchanged, except if it also appears
as the target bitmap. Any bits already set in target will still be set
after the merge, i.e., this operation does not clear the target. On
error, target is unchanged.
The resulting bitmap will count as dirty any clusters that were dirty
in any of the source bitmaps. This can be used to achieve backup check-
points, or in simpler usages, to copy bitmaps.
Returns
• nothing on success
• If node is not a valid block device, DeviceNotFound
• If any bitmap in bitmaps or target is not found, GenericError
• If any of the bitmaps have different sizes or granularities, Gener-
icError
Since
4.0
Example
-> { "execute": "block-dirty-bitmap-merge",
"arguments": { "node": "drive0", "target": "bitmap0",
"bitmaps": ["bitmap1"] } }
<- { "return": {} }
BlockDirtyBitmapSha256 (Object)
SHA256 hash of dirty bitmap data
Members
sha256: string
ASCII representation of SHA256 bitmap hash
Since
2.10
x-debug-block-dirty-bitmap-sha256 (Command)
Get bitmap SHA256.
Features
unstable
This command is meant for debugging.
Returns
• BlockDirtyBitmapSha256 on success
• If node is not a valid block device, DeviceNotFound
• If name is not found or if hashing has failed, GenericError with an
explanation
Since
2.10
blockdev-mirror (Command)
Start mirroring a block device's writes to a new destination.
Arguments
job-id: string (optional)
identifier for the newly-created block job. If omitted, the de-
vice name will be used. (Since 2.7)
device: string
The device name or node-name of a root node whose writes should
be mirrored.
target: string
the id or node-name of the block device to mirror to. This
mustn't be attached to guest.
replaces: string (optional)
with sync=full graph node name to be replaced by the new image
when a whole image copy is done. This can be used to repair bro-
ken Quorum files. By default, device is replaced, although im-
plicitly created filters on it are kept.
speed: int (optional)
the maximum speed, in bytes per second
sync: MirrorSyncMode
what parts of the disk image should be copied to the destination
(all the disk, only the sectors allocated in the topmost image,
or only new I/O).
granularity: int (optional)
granularity of the dirty bitmap, default is 64K if the image
format doesn't have clusters, 4K if the clusters are smaller
than that, else the cluster size. Must be a power of 2 between
512 and 64M
buf-size: int (optional)
maximum amount of data in flight from source to target
on-source-error: BlockdevOnError (optional)
the action to take on an error on the source, default 'report'.
'stop' and 'enospc' can only be used if the block device sup-
ports io-status (see BlockInfo).
on-target-error: BlockdevOnError (optional)
the action to take on an error on the target, default 'report'
(no limitations, since this applies to a different block device
than device).
filter-node-name: string (optional)
the node name that should be assigned to the filter driver that
the mirror job inserts into the graph above device. If this op-
tion is not given, a node name is autogenerated. (Since: 2.9)
copy-mode: MirrorCopyMode (optional)
when to copy data to the destination; defaults to 'background'
(Since: 3.0)
auto-finalize: boolean (optional)
When false, this job will wait in a PENDING state after it has
finished its work, waiting for block-job-finalize before making
any block graph changes. When true, this job will automatically
perform its abort or commit actions. Defaults to true. (Since
3.1)
auto-dismiss: boolean (optional)
When false, this job will wait in a CONCLUDED state after it has
completely ceased all work, and awaits block-job-dismiss. When
true, this job will automatically disappear from the query list
without user intervention. Defaults to true. (Since 3.1)
Returns
nothing on success.
Since
2.6
Example
-> { "execute": "blockdev-mirror",
"arguments": { "device": "ide-hd0",
"target": "target0",
"sync": "full" } }
<- { "return": {} }
BlockIOThrottle (Object)
A set of parameters describing block throttling.
Members
device: string (optional)
Block device name
id: string (optional)
The name or QOM path of the guest device (since: 2.8)
bps: int
total throughput limit in bytes per second
bps_rd: int
read throughput limit in bytes per second
bps_wr: int
write throughput limit in bytes per second
iops: int
total I/O operations per second
iops_rd: int
read I/O operations per second
iops_wr: int
write I/O operations per second
bps_max: int (optional)
total throughput limit during bursts, in bytes (Since 1.7)
bps_rd_max: int (optional)
read throughput limit during bursts, in bytes (Since 1.7)
bps_wr_max: int (optional)
write throughput limit during bursts, in bytes (Since 1.7)
iops_max: int (optional)
total I/O operations per second during bursts, in bytes (Since
1.7)
iops_rd_max: int (optional)
read I/O operations per second during bursts, in bytes (Since
1.7)
iops_wr_max: int (optional)
write I/O operations per second during bursts, in bytes (Since
1.7)
bps_max_length: int (optional)
maximum length of the bps_max burst period, in seconds. It must
only be set if bps_max is set as well. Defaults to 1. (Since
2.6)
bps_rd_max_length: int (optional)
maximum length of the bps_rd_max burst period, in seconds. It
must only be set if bps_rd_max is set as well. Defaults to 1.
(Since 2.6)
bps_wr_max_length: int (optional)
maximum length of the bps_wr_max burst period, in seconds. It
must only be set if bps_wr_max is set as well. Defaults to 1.
(Since 2.6)
iops_max_length: int (optional)
maximum length of the iops burst period, in seconds. It must
only be set if iops_max is set as well. Defaults to 1. (Since
2.6)
iops_rd_max_length: int (optional)
maximum length of the iops_rd_max burst period, in seconds. It
must only be set if iops_rd_max is set as well. Defaults to 1.
(Since 2.6)
iops_wr_max_length: int (optional)
maximum length of the iops_wr_max burst period, in seconds. It
must only be set if iops_wr_max is set as well. Defaults to 1.
(Since 2.6)
iops_size: int (optional)
an I/O size in bytes (Since 1.7)
group: string (optional)
throttle group name (Since 2.4)
Features
deprecated
Member device is deprecated. Use id instead.
Since
1.1
ThrottleLimits (Object)
Limit parameters for throttling. Since some limit combinations are il-
legal, limits should always be set in one transaction. All fields are
optional. When setting limits, if a field is missing the current value
is not changed.
Members
iops-total: int (optional)
limit total I/O operations per second
iops-total-max: int (optional)
I/O operations burst
iops-total-max-length: int (optional)
length of the iops-total-max burst period, in seconds It must
only be set if iops-total-max is set as well.
iops-read: int (optional)
limit read operations per second
iops-read-max: int (optional)
I/O operations read burst
iops-read-max-length: int (optional)
length of the iops-read-max burst period, in seconds It must
only be set if iops-read-max is set as well.
iops-write: int (optional)
limit write operations per second
iops-write-max: int (optional)
I/O operations write burst
iops-write-max-length: int (optional)
length of the iops-write-max burst period, in seconds It must
only be set if iops-write-max is set as well.
bps-total: int (optional)
limit total bytes per second
bps-total-max: int (optional)
total bytes burst
bps-total-max-length: int (optional)
length of the bps-total-max burst period, in seconds. It must
only be set if bps-total-max is set as well.
bps-read: int (optional)
limit read bytes per second
bps-read-max: int (optional)
total bytes read burst
bps-read-max-length: int (optional)
length of the bps-read-max burst period, in seconds It must only
be set if bps-read-max is set as well.
bps-write: int (optional)
limit write bytes per second
bps-write-max: int (optional)
total bytes write burst
bps-write-max-length: int (optional)
length of the bps-write-max burst period, in seconds It must
only be set if bps-write-max is set as well.
iops-size: int (optional)
when limiting by iops max size of an I/O in bytes
Since
2.11
ThrottleGroupProperties (Object)
Properties for throttle-group objects.
Members
limits: ThrottleLimits (optional)
limits to apply for this throttle group
x-iops-total: int (optional)
Not documented
x-iops-total-max: int (optional)
Not documented
x-iops-total-max-length: int (optional)
Not documented
x-iops-read: int (optional)
Not documented
x-iops-read-max: int (optional)
Not documented
x-iops-read-max-length: int (optional)
Not documented
x-iops-write: int (optional)
Not documented
x-iops-write-max: int (optional)
Not documented
x-iops-write-max-length: int (optional)
Not documented
x-bps-total: int (optional)
Not documented
x-bps-total-max: int (optional)
Not documented
x-bps-total-max-length: int (optional)
Not documented
x-bps-read: int (optional)
Not documented
x-bps-read-max: int (optional)
Not documented
x-bps-read-max-length: int (optional)
Not documented
x-bps-write: int (optional)
Not documented
x-bps-write-max: int (optional)
Not documented
x-bps-write-max-length: int (optional)
Not documented
x-iops-size: int (optional)
Not documented
Features
unstable
All members starting with x- are aliases for the same key with-
out x- in the limits object. This is not a stable interface and
may be removed or changed incompatibly in the future. Use lim-
its for a supported stable interface.
Since
2.11
block-stream (Command)
Copy data from a backing file into a block device.
The block streaming operation is performed in the background until the
entire backing file has been copied. This command returns immediately
once streaming has started. The status of ongoing block streaming op-
erations can be checked with query-block-jobs. The operation can be
stopped before it has completed using the block-job-cancel command.
The node that receives the data is called the top image, can be located
in any part of the chain (but always above the base image; see below)
and can be specified using its device or node name. Earlier qemu ver-
sions only allowed 'device' to name the top level node; presence of the
'base-node' parameter during introspection can be used as a witness of
the enhanced semantics of 'device'.
If a base file is specified then sectors are not copied from that base
file and its backing chain. This can be used to stream a subset of the
backing file chain instead of flattening the entire image. When
streaming completes the image file will have the base file as its back-
ing file, unless that node was changed while the job was running. In
that case, base's parent's backing (or filtered, whichever exists)
child (i.e., base at the beginning of the job) will be the new backing
file.
On successful completion the image file is updated to drop the backing
file and the BLOCK_JOB_COMPLETED event is emitted.
In case device is a filter node, block-stream modifies the first
non-filter overlay node below it to point to the new backing node in-
stead of modifying device itself.
Arguments
job-id: string (optional)
identifier for the newly-created block job. If omitted, the de-
vice name will be used. (Since 2.7)
device: string
the device or node name of the top image
base: string (optional)
the common backing file name. It cannot be set if base-node or
bottom is also set.
base-node: string (optional)
the node name of the backing file. It cannot be set if base or
bottom is also set. (Since 2.8)
bottom: string (optional)
the last node in the chain that should be streamed into top. It
cannot be set if base or base-node is also set. It cannot be
filter node. (Since 6.0)
backing-file: string (optional)
The backing file string to write into the top image. This file-
name is not validated.
If a pathname string is such that it cannot be resolved by QEMU,
that means that subsequent QMP or HMP commands must use
node-names for the image in question, as filename lookup methods
will fail.
If not specified, QEMU will automatically determine the backing
file string to use, or error out if there is no obvious choice.
Care should be taken when specifying the string, to specify a
valid filename or protocol. (Since 2.1)
speed: int (optional)
the maximum speed, in bytes per second
on-error: BlockdevOnError (optional)
the action to take on an error (default report). 'stop' and
'enospc' can only be used if the block device supports io-status
(see BlockInfo). Since 1.3.
filter-node-name: string (optional)
the node name that should be assigned to the filter driver that
the stream job inserts into the graph above device. If this op-
tion is not given, a node name is autogenerated. (Since: 6.0)
auto-finalize: boolean (optional)
When false, this job will wait in a PENDING state after it has
finished its work, waiting for block-job-finalize before making
any block graph changes. When true, this job will automatically
perform its abort or commit actions. Defaults to true. (Since
3.1)
auto-dismiss: boolean (optional)
When false, this job will wait in a CONCLUDED state after it has
completely ceased all work, and awaits block-job-dismiss. When
true, this job will automatically disappear from the query list
without user intervention. Defaults to true. (Since 3.1)
Returns
• Nothing on success.
• If device does not exist, DeviceNotFound.
Since
1.1
Example
-> { "execute": "block-stream",
"arguments": { "device": "virtio0",
"base": "/tmp/master.qcow2" } }
<- { "return": {} }
block-job-set-speed (Command)
Set maximum speed for a background block operation.
This command can only be issued when there is an active block job.
Throttling can be disabled by setting the speed to 0.
Arguments
device: string
The job identifier. This used to be a device name (hence the
name of the parameter), but since QEMU 2.7 it can have other
values.
speed: int
the maximum speed, in bytes per second, or 0 for unlimited. De-
faults to 0.
Returns
• Nothing on success
• If no background operation is active on this device, DeviceNotActive
Since
1.1
block-job-cancel (Command)
Stop an active background block operation.
This command returns immediately after marking the active background
block operation for cancellation. It is an error to call this command
if no operation is in progress.
The operation will cancel as soon as possible and then emit the
BLOCK_JOB_CANCELLED event. Before that happens the job is still visi-
ble when enumerated using query-block-jobs.
Note that if you issue 'block-job-cancel' after 'drive-mirror' has in-
dicated (via the event BLOCK_JOB_READY) that the source and destination
are synchronized, then the event triggered by this command changes to
BLOCK_JOB_COMPLETED, to indicate that the mirroring has ended and the
destination now has a point-in-time copy tied to the time of the can-
cellation.
For streaming, the image file retains its backing file unless the
streaming operation happens to complete just as it is being cancelled.
A new streaming operation can be started at a later time to finish
copying all data from the backing file.
Arguments
device: string
The job identifier. This used to be a device name (hence the
name of the parameter), but since QEMU 2.7 it can have other
values.
force: boolean (optional)
If true, and the job has already emitted the event
BLOCK_JOB_READY, abandon the job immediately (even if it is
paused) instead of waiting for the destination to complete its
final synchronization (since 1.3)
Returns
• Nothing on success
• If no background operation is active on this device, DeviceNotActive
Since
1.1
block-job-pause (Command)
Pause an active background block operation.
This command returns immediately after marking the active background
block operation for pausing. It is an error to call this command if no
operation is in progress or if the job is already paused.
The operation will pause as soon as possible. No event is emitted when
the operation is actually paused. Cancelling a paused job automati-
cally resumes it.
Arguments
device: string
The job identifier. This used to be a device name (hence the
name of the parameter), but since QEMU 2.7 it can have other
values.
Returns
• Nothing on success
• If no background operation is active on this device, DeviceNotActive
Since
1.3
block-job-resume (Command)
Resume an active background block operation.
This command returns immediately after resuming a paused background
block operation. It is an error to call this command if no operation
is in progress or if the job is not paused.
This command also clears the error status of the job.
Arguments
device: string
The job identifier. This used to be a device name (hence the
name of the parameter), but since QEMU 2.7 it can have other
values.
Returns
• Nothing on success
• If no background operation is active on this device, DeviceNotActive
Since
1.3
block-job-complete (Command)
Manually trigger completion of an active background block operation.
This is supported for drive mirroring, where it also switches the de-
vice to write to the target path only. The ability to complete is sig-
naled with a BLOCK_JOB_READY event.
This command completes an active background block operation syn-
chronously. The ordering of this command's return with the
BLOCK_JOB_COMPLETED event is not defined. Note that if an I/O error
occurs during the processing of this command: 1) the command itself
will fail; 2) the error will be processed according to the rerror/wer-
ror arguments that were specified when starting the operation.
A cancelled or paused job cannot be completed.
Arguments
device: string
The job identifier. This used to be a device name (hence the
name of the parameter), but since QEMU 2.7 it can have other
values.
Returns
• Nothing on success
• If no background operation is active on this device, DeviceNotActive
Since
1.3
block-job-dismiss (Command)
For jobs that have already concluded, remove them from the
block-job-query list. This command only needs to be run for jobs which
were started with QEMU 2.12+ job lifetime management semantics.
This command will refuse to operate on any job that has not yet reached
its terminal state, JOB_STATUS_CONCLUDED. For jobs that make use of the
BLOCK_JOB_READY event, block-job-cancel or block-job-complete will
still need to be used as appropriate.
Arguments
id: string
The job identifier.
Returns
Nothing on success
Since
2.12
block-job-finalize (Command)
Once a job that has manual=true reaches the pending state, it can be
instructed to finalize any graph changes and do any necessary cleanup
via this command. For jobs in a transaction, instructing one job to
finalize will force ALL jobs in the transaction to finalize, so it is
only necessary to instruct a single member job to finalize.
Arguments
id: string
The job identifier.
Returns
Nothing on success
Since
2.12
BlockdevDiscardOptions (Enum)
Determines how to handle discard requests.
Values
ignore Ignore the request
unmap Forward as an unmap request
Since
2.9
BlockdevDetectZeroesOptions (Enum)
Describes the operation mode for the automatic conversion of plain zero
writes by the OS to driver specific optimized zero write commands.
Values
off Disabled (default)
on Enabled
unmap Enabled and even try to unmap blocks if possible. This requires
also that BlockdevDiscardOptions is set to unmap for this de-
vice.
Since
2.1
BlockdevAioOptions (Enum)
Selects the AIO backend to handle I/O requests
Values
threads
Use qemu's thread pool
native Use native AIO backend (only Linux and Windows)
io_uring (If: CONFIG_LINUX_IO_URING)
Use linux io_uring (since 5.0)
Since
2.9
BlockdevCacheOptions (Object)
Includes cache-related options for block devices
Members
direct: boolean (optional)
enables use of O_DIRECT (bypass the host page cache; default:
false)
no-flush: boolean (optional)
ignore any flush requests for the device (default: false)
Since
2.9
BlockdevDriver (Enum)
Drivers that are supported in block device operations.
Values
throttle
Since 2.11
nvme Since 2.12
copy-on-read
Since 3.0
blklogwrites
Since 3.0
blkreplay
Since 4.2
compress
Since 5.0
copy-before-write
Since 6.2
snapshot-access
Since 7.0
blkdebug
Not documented
blkverify
Not documented
bochs Not documented
cloop Not documented
dmg Not documented
file Not documented
ftp Not documented
ftps Not documented
gluster
Not documented
host_cdrom (If: HAVE_HOST_BLOCK_DEVICE)
Not documented
host_device (If: HAVE_HOST_BLOCK_DEVICE)
Not documented
http Not documented
https Not documented
io_uring (If: CONFIG_BLKIO)
Not documented
iscsi Not documented
luks Not documented
nbd Not documented
nfs Not documented
null-aio
Not documented
null-co
Not documented
nvme-io_uring (If: CONFIG_BLKIO)
Not documented
parallels
Not documented
preallocate
Not documented
qcow Not documented
qcow2 Not documented
qed Not documented
quorum Not documented
raw Not documented
rbd Not documented
replication (If: CONFIG_REPLICATION)
Not documented
ssh Not documented
vdi Not documented
vhdx Not documented
virtio-blk-vfio-pci (If: CONFIG_BLKIO)
Not documented
virtio-blk-vhost-user (If: CONFIG_BLKIO)
Not documented
virtio-blk-vhost-vdpa (If: CONFIG_BLKIO)
Not documented
vmdk Not documented
vpc Not documented
vvfat Not documented
Since
2.9
BlockdevOptionsFile (Object)
Driver specific block device options for the file backend.
Members
filename: string
path to the image file
pr-manager: string (optional)
the id for the object that will handle persistent reservations
for this device (default: none, forward the commands via SG_IO;
since 2.11)
aio: BlockdevAioOptions (optional)
AIO backend (default: threads) (since: 2.8)
aio-max-batch: int (optional)
maximum number of requests to batch together into a single sub-
mission in the AIO backend. The smallest value between this and
the aio-max-batch value of the IOThread object is chosen. 0
means that the AIO backend will handle it automatically. (de-
fault: 0, since 6.2)
locking: OnOffAuto (optional)
whether to enable file locking. If set to 'auto', only enable
when Open File Descriptor (OFD) locking API is available (de-
fault: auto, since 2.10)
drop-cache: boolean (optional) (If: CONFIG_LINUX)
invalidate page cache during live migration. This prevents
stale data on the migration destination with cache.direct=off.
Currently only supported on Linux hosts. (default: on, since:
4.0)
x-check-cache-dropped: boolean (optional)
whether to check that page cache was dropped on live migration.
May cause noticeable delays if the image file is large, do not
use in production. (default: off) (since: 3.0)
Features
dynamic-auto-read-only
If present, enabled auto-read-only means that the driver will
open the image read-only at first, dynamically reopen the image
file read-write when the first writer is attached to the node
and reopen read-only when the last writer is detached. This al-
lows giving QEMU write permissions only on demand when an opera-
tion actually needs write access.
unstable
Member x-check-cache-dropped is meant for debugging.
Since
2.9
BlockdevOptionsNull (Object)
Driver specific block device options for the null backend.
Members
size: int (optional)
size of the device in bytes.
latency-ns: int (optional)
emulated latency (in nanoseconds) in processing requests. De-
fault to zero which completes requests immediately. (Since 2.4)
read-zeroes: boolean (optional)
if true, reads from the device produce zeroes; if false, the
buffer is left unchanged. (default: false; since: 4.1)
Since
2.9
BlockdevOptionsNVMe (Object)
Driver specific block device options for the NVMe backend.
Members
device: string
PCI controller address of the NVMe device in format hhhh:bb:ss.f
(host:bus:slot.function)
namespace: int
namespace number of the device, starting from 1.
Note that the PCI device must have been unbound from any host kernel
driver before instructing QEMU to add the blockdev.
Since
2.12
BlockdevOptionsVVFAT (Object)
Driver specific block device options for the vvfat protocol.
Members
dir: string
directory to be exported as FAT image
fat-type: int (optional)
FAT type: 12, 16 or 32
floppy: boolean (optional)
whether to export a floppy image (true) or partitioned hard disk
(false; default)
label: string (optional)
set the volume label, limited to 11 bytes. FAT16 and FAT32 tra-
ditionally have some restrictions on labels, which are ignored
by most operating systems. Defaults to "QEMU VVFAT". (since
2.4)
rw: boolean (optional)
whether to allow write operations (default: false)
Since
2.9
BlockdevOptionsGenericFormat (Object)
Driver specific block device options for image format that have no op-
tion besides their data source.
Members
file: BlockdevRef
reference to or definition of the data source block device
Since
2.9
BlockdevOptionsLUKS (Object)
Driver specific block device options for LUKS.
Members
key-secret: string (optional)
the ID of a QCryptoSecret object providing the decryption key
(since 2.6). Mandatory except when doing a metadata-only probe
of the image.
The members of BlockdevOptionsGenericFormat
Since
2.9
BlockdevOptionsGenericCOWFormat (Object)
Driver specific block device options for image format that have no op-
tion besides their data source and an optional backing file.
Members
backing: BlockdevRefOrNull (optional)
reference to or definition of the backing file block device,
null disables the backing file entirely. Defaults to the back-
ing file stored the image file.
The members of BlockdevOptionsGenericFormat
Since
2.9
Qcow2OverlapCheckMode (Enum)
General overlap check modes.
Values
none Do not perform any checks
constant
Perform only checks which can be done in constant time and with-
out reading anything from disk
cached Perform only checks which can be done without reading anything
from disk
all Perform all available overlap checks
Since
2.9
Qcow2OverlapCheckFlags (Object)
Structure of flags for each metadata structure. Setting a field to
'true' makes qemu guard that structure against unintended overwriting.
The default value is chosen according to the template given.
Members
template: Qcow2OverlapCheckMode (optional)
Specifies a template mode which can be adjusted using the other
flags, defaults to 'cached'
bitmap-directory: boolean (optional)
since 3.0
main-header: boolean (optional)
Not documented
active-l1: boolean (optional)
Not documented
active-l2: boolean (optional)
Not documented
refcount-table: boolean (optional)
Not documented
refcount-block: boolean (optional)
Not documented
snapshot-table: boolean (optional)
Not documented
inactive-l1: boolean (optional)
Not documented
inactive-l2: boolean (optional)
Not documented
Since
2.9
Qcow2OverlapChecks (Alternate)
Specifies which metadata structures should be guarded against unin-
tended overwriting.
Members
flags: Qcow2OverlapCheckFlags
set of flags for separate specification of each metadata struc-
ture type
mode: Qcow2OverlapCheckMode
named mode which chooses a specific set of flags
Since
2.9
BlockdevQcowEncryptionFormat (Enum)
Values
aes AES-CBC with plain64 initialization vectors
Since
2.10
BlockdevQcowEncryption (Object)
Members
format: BlockdevQcowEncryptionFormat
Not documented
The members of QCryptoBlockOptionsQCow when format is "aes"
Since
2.10
BlockdevOptionsQcow (Object)
Driver specific block device options for qcow.
Members
encrypt: BlockdevQcowEncryption (optional)
Image decryption options. Mandatory for encrypted images, except
when doing a metadata-only probe of the image.
The members of BlockdevOptionsGenericCOWFormat
Since
2.10
BlockdevQcow2EncryptionFormat (Enum)
Values
aes AES-CBC with plain64 initialization vectors
luks Not documented
Since
2.10
BlockdevQcow2Encryption (Object)
Members
format: BlockdevQcow2EncryptionFormat
Not documented
The members of QCryptoBlockOptionsQCow when format is "aes"
The members of QCryptoBlockOptionsLUKS when format is "luks"
Since
2.10
BlockdevOptionsPreallocate (Object)
Filter driver intended to be inserted between format and protocol node
and do preallocation in protocol node on write.
Members
prealloc-align: int (optional)
on preallocation, align file length to this number, default
1048576 (1M)
prealloc-size: int (optional)
how much to preallocate, default 134217728 (128M)
The members of BlockdevOptionsGenericFormat
Since
6.0
BlockdevOptionsQcow2 (Object)
Driver specific block device options for qcow2.
Members
lazy-refcounts: boolean (optional)
whether to enable the lazy refcounts feature (default is taken
from the image file)
pass-discard-request: boolean (optional)
whether discard requests to the qcow2 device should be forwarded
to the data source
pass-discard-snapshot: boolean (optional)
whether discard requests for the data source should be issued
when a snapshot operation (e.g. deleting a snapshot) frees
clusters in the qcow2 file
pass-discard-other: boolean (optional)
whether discard requests for the data source should be issued on
other occasions where a cluster gets freed
overlap-check: Qcow2OverlapChecks (optional)
which overlap checks to perform for writes to the image, de-
faults to 'cached' (since 2.2)
cache-size: int (optional)
the maximum total size of the L2 table and refcount block caches
in bytes (since 2.2)
l2-cache-size: int (optional)
the maximum size of the L2 table cache in bytes (since 2.2)
l2-cache-entry-size: int (optional)
the size of each entry in the L2 cache in bytes. It must be a
power of two between 512 and the cluster size. The default value
is the cluster size (since 2.12)
refcount-cache-size: int (optional)
the maximum size of the refcount block cache in bytes (since
2.2)
cache-clean-interval: int (optional)
clean unused entries in the L2 and refcount caches. The interval
is in seconds. The default value is 600 on supporting platforms,
and 0 on other platforms. 0 disables this feature. (since 2.5)
encrypt: BlockdevQcow2Encryption (optional)
Image decryption options. Mandatory for encrypted images, except
when doing a metadata-only probe of the image. (since 2.10)
data-file: BlockdevRef (optional)
reference to or definition of the external data file. This may
only be specified for images that require an external data file.
If it is not specified for such an image, the data file name is
loaded from the image file. (since 4.0)
The members of BlockdevOptionsGenericCOWFormat
Since
2.9
SshHostKeyCheckMode (Enum)
Values
none Don't check the host key at all
hash Compare the host key with a given hash
known_hosts
Check the host key against the known_hosts file
Since
2.12
SshHostKeyCheckHashType (Enum)
Values
md5 The given hash is an md5 hash
sha1 The given hash is an sha1 hash
sha256 The given hash is an sha256 hash
Since
2.12
SshHostKeyHash (Object)
Members
type: SshHostKeyCheckHashType
The hash algorithm used for the hash
hash: string
The expected hash value
Since
2.12
SshHostKeyCheck (Object)
Members
mode: SshHostKeyCheckMode
Not documented
The members of SshHostKeyHash when mode is "hash"
Since
2.12
BlockdevOptionsSsh (Object)
Members
server: InetSocketAddress
host address
path: string
path to the image on the host
user: string (optional)
user as which to connect, defaults to current local user name
host-key-check: SshHostKeyCheck (optional)
Defines how and what to check the host key against (default:
known_hosts)
Since
2.9
BlkdebugEvent (Enum)
Trigger events supported by blkdebug.
Values
l1_shrink_write_table
write zeros to the l1 table to shrink image. (since 2.11)
l1_shrink_free_l2_clusters
discard the l2 tables. (since 2.11)
cor_write
a write due to copy-on-read (since 2.11)
cluster_alloc_space
an allocation of file space for a cluster (since 4.1)
none triggers once at creation of the blkdebug node (since 4.1)
l1_update
Not documented
l1_grow_alloc_table
Not documented
l1_grow_write_table
Not documented
l1_grow_activate_table
Not documented
l2_load
Not documented
l2_update
Not documented
l2_update_compressed
Not documented
l2_alloc_cow_read
Not documented
l2_alloc_write
Not documented
read_aio
Not documented
read_backing_aio
Not documented
read_compressed
Not documented
write_aio
Not documented
write_compressed
Not documented
vmstate_load
Not documented
vmstate_save
Not documented
cow_read
Not documented
cow_write
Not documented
reftable_load
Not documented
reftable_grow
Not documented
reftable_update
Not documented
refblock_load
Not documented
refblock_update
Not documented
refblock_update_part
Not documented
refblock_alloc
Not documented
refblock_alloc_hookup
Not documented
refblock_alloc_write
Not documented
refblock_alloc_write_blocks
Not documented
refblock_alloc_write_table
Not documented
refblock_alloc_switch_table
Not documented
cluster_alloc
Not documented
cluster_alloc_bytes
Not documented
cluster_free
Not documented
flush_to_os
Not documented
flush_to_disk
Not documented
pwritev_rmw_head
Not documented
pwritev_rmw_after_head
Not documented
pwritev_rmw_tail
Not documented
pwritev_rmw_after_tail
Not documented
pwritev
Not documented
pwritev_zero
Not documented
pwritev_done
Not documented
empty_image_prepare
Not documented
Since
2.9
BlkdebugIOType (Enum)
Kinds of I/O that blkdebug can inject errors in.
Values
read .bdrv_co_preadv()
write .bdrv_co_pwritev()
write-zeroes
.bdrv_co_pwrite_zeroes()
discard
.bdrv_co_pdiscard()
flush .bdrv_co_flush_to_disk()
block-status
.bdrv_co_block_status()
Since
4.1
BlkdebugInjectErrorOptions (Object)
Describes a single error injection for blkdebug.
Members
event: BlkdebugEvent
trigger event
state: int (optional)
the state identifier blkdebug needs to be in to actually trigger
the event; defaults to "any"
iotype: BlkdebugIOType (optional)
the type of I/O operations on which this error should be in-
jected; defaults to "all read, write, write-zeroes, discard, and
flush operations" (since: 4.1)
errno: int (optional)
error identifier (errno) to be returned; defaults to EIO
sector: int (optional)
specifies the sector index which has to be affected in order to
actually trigger the event; defaults to "any sector"
once: boolean (optional)
disables further events after this one has been triggered; de-
faults to false
immediately: boolean (optional)
fail immediately; defaults to false
Since
2.9
BlkdebugSetStateOptions (Object)
Describes a single state-change event for blkdebug.
Members
event: BlkdebugEvent
trigger event
state: int (optional)
the current state identifier blkdebug needs to be in; defaults
to "any"
new_state: int
the state identifier blkdebug is supposed to assume if this
event is triggered
Since
2.9
BlockdevOptionsBlkdebug (Object)
Driver specific block device options for blkdebug.
Members
image: BlockdevRef
underlying raw block device (or image file)
config: string (optional)
filename of the configuration file
align: int (optional)
required alignment for requests in bytes, must be positive power
of 2, or 0 for default
max-transfer: int (optional)
maximum size for I/O transfers in bytes, must be positive multi-
ple of align and of the underlying file's request alignment (but
need not be a power of 2), or 0 for default (since 2.10)
opt-write-zero: int (optional)
preferred alignment for write zero requests in bytes, must be
positive multiple of align and of the underlying file's request
alignment (but need not be a power of 2), or 0 for default
(since 2.10)
max-write-zero: int (optional)
maximum size for write zero requests in bytes, must be positive
multiple of align, of opt-write-zero, and of the underlying
file's request alignment (but need not be a power of 2), or 0
for default (since 2.10)
opt-discard: int (optional)
preferred alignment for discard requests in bytes, must be posi-
tive multiple of align and of the underlying file's request
alignment (but need not be a power of 2), or 0 for default
(since 2.10)
max-discard: int (optional)
maximum size for discard requests in bytes, must be positive
multiple of align, of opt-discard, and of the underlying file's
request alignment (but need not be a power of 2), or 0 for de-
fault (since 2.10)
inject-error: array of BlkdebugInjectErrorOptions (optional)
array of error injection descriptions
set-state: array of BlkdebugSetStateOptions (optional)
array of state-change descriptions
take-child-perms: array of BlockPermission (optional)
Permissions to take on image in addition to what is necessary
anyway (which depends on how the blkdebug node is used). De-
faults to none. (since 5.0)
unshare-child-perms: array of BlockPermission (optional)
Permissions not to share on image in addition to what cannot be
shared anyway (which depends on how the blkdebug node is used).
Defaults to none. (since 5.0)
Since
2.9
BlockdevOptionsBlklogwrites (Object)
Driver specific block device options for blklogwrites.
Members
file: BlockdevRef
block device
log: BlockdevRef
block device used to log writes to file
log-sector-size: int (optional)
sector size used in logging writes to file, determines granular-
ity of offsets and sizes of writes (default: 512)
log-append: boolean (optional)
append to an existing log (default: false)
log-super-update-interval: int (optional)
interval of write requests after which the log super block is
updated to disk (default: 4096)
Since
3.0
BlockdevOptionsBlkverify (Object)
Driver specific block device options for blkverify.
Members
test: BlockdevRef
block device to be tested
raw: BlockdevRef
raw image used for verification
Since
2.9
BlockdevOptionsBlkreplay (Object)
Driver specific block device options for blkreplay.
Members
image: BlockdevRef
disk image which should be controlled with blkreplay
Since
4.2
QuorumReadPattern (Enum)
An enumeration of quorum read patterns.
Values
quorum read all the children and do a quorum vote on reads
fifo read only from the first child that has not failed
Since
2.9
BlockdevOptionsQuorum (Object)
Driver specific block device options for Quorum
Members
blkverify: boolean (optional)
true if the driver must print content mismatch
set to false by default
children: array of BlockdevRef
the children block devices to use
vote-threshold: int
the vote limit under which a read will fail
rewrite-corrupted: boolean (optional)
rewrite corrupted data when quorum is reached (Since 2.1)
read-pattern: QuorumReadPattern (optional)
choose read pattern and set to quorum by default (Since 2.2)
Since
2.9
BlockdevOptionsGluster (Object)
Driver specific block device options for Gluster
Members
volume: string
name of gluster volume where VM image resides
path: string
absolute path to image file in gluster volume
server: array of SocketAddress
gluster servers description
debug: int (optional)
libgfapi log level (default '4' which is Error) (Since 2.8)
logfile: string (optional)
libgfapi log file (default /dev/stderr) (Since 2.8)
Since
2.9
BlockdevOptionsIoUring (Object)
Driver specific block device options for the io_uring backend.
Members
filename: string
path to the image file
Since
7.2
If
CONFIG_BLKIO
BlockdevOptionsNvmeIoUring (Object)
Driver specific block device options for the nvme-io_uring backend.
Members
path: string
path to the NVMe namespace's character device (e.g. /dev/ng0n1).
Since
7.2
If
CONFIG_BLKIO
BlockdevOptionsVirtioBlkVfioPci (Object)
Driver specific block device options for the virtio-blk-vfio-pci back-
end.
Members
path: string
path to the PCI device's sysfs directory (e.g. /sys/bus/pci/de-
vices/0000:00:01.0).
Since
7.2
If
CONFIG_BLKIO
BlockdevOptionsVirtioBlkVhostUser (Object)
Driver specific block device options for the virtio-blk-vhost-user
backend.
Members
path: string
path to the vhost-user UNIX domain socket.
Since
7.2
If
CONFIG_BLKIO
BlockdevOptionsVirtioBlkVhostVdpa (Object)
Driver specific block device options for the virtio-blk-vhost-vdpa
backend.
Members
path: string
path to the vhost-vdpa character device.
Since
7.2
If
CONFIG_BLKIO
IscsiTransport (Enum)
An enumeration of libiscsi transport types
Values
tcp Not documented
iser Not documented
Since
2.9
IscsiHeaderDigest (Enum)
An enumeration of header digests supported by libiscsi
Values
crc32c Not documented
none Not documented
crc32c-none
Not documented
none-crc32c
Not documented
Since
2.9
BlockdevOptionsIscsi (Object)
Members
transport: IscsiTransport
The iscsi transport type
portal: string
The address of the iscsi portal
target: string
The target iqn name
lun: int (optional)
LUN to connect to. Defaults to 0.
user: string (optional)
User name to log in with. If omitted, no CHAP authentication is
performed.
password-secret: string (optional)
The ID of a QCryptoSecret object providing the password for the
login. This option is required if user is specified.
initiator-name: string (optional)
The iqn name we want to identify to the target as. If this op-
tion is not specified, an initiator name is generated automati-
cally.
header-digest: IscsiHeaderDigest (optional)
The desired header digest. Defaults to none-crc32c.
timeout: int (optional)
Timeout in seconds after which a request will timeout. 0 means
no timeout and is the default.
Driver specific block device options for iscsi
Since
2.9
RbdAuthMode (Enum)
Values
cephx Not documented
none Not documented
Since
3.0
RbdImageEncryptionFormat (Enum)
Values
luks Not documented
luks2 Not documented
Since
6.1
RbdEncryptionOptionsLUKSBase (Object)
Members
key-secret: string
ID of a QCryptoSecret object providing a passphrase for unlock-
ing the encryption
Since
6.1
RbdEncryptionCreateOptionsLUKSBase (Object)
Members
cipher-alg: QCryptoCipherAlgorithm (optional)
The encryption algorithm
The members of RbdEncryptionOptionsLUKSBase
Since
6.1
RbdEncryptionOptionsLUKS (Object)
Members
The members of RbdEncryptionOptionsLUKSBase
Since
6.1
RbdEncryptionOptionsLUKS2 (Object)
Members
The members of RbdEncryptionOptionsLUKSBase
Since
6.1
RbdEncryptionCreateOptionsLUKS (Object)
Members
The members of RbdEncryptionCreateOptionsLUKSBase
Since
6.1
RbdEncryptionCreateOptionsLUKS2 (Object)
Members
The members of RbdEncryptionCreateOptionsLUKSBase
Since
6.1
RbdEncryptionOptions (Object)
Members
format: RbdImageEncryptionFormat
Not documented
The members of RbdEncryptionOptionsLUKS when format is "luks"
The members of RbdEncryptionOptionsLUKS2 when format is "luks2"
Since
6.1
RbdEncryptionCreateOptions (Object)
Members
format: RbdImageEncryptionFormat
Not documented
The members of RbdEncryptionCreateOptionsLUKS when format is "luks"
The members of RbdEncryptionCreateOptionsLUKS2 when format is "luks2"
Since
6.1
BlockdevOptionsRbd (Object)
Members
pool: string
Ceph pool name.
namespace: string (optional)
Rados namespace name in the Ceph pool. (Since 5.0)
image: string
Image name in the Ceph pool.
conf: string (optional)
path to Ceph configuration file. Values in the configuration
file will be overridden by options specified via QAPI.
snapshot: string (optional)
Ceph snapshot name.
encrypt: RbdEncryptionOptions (optional)
Image encryption options. (Since 6.1)
user: string (optional)
Ceph id name.
auth-client-required: array of RbdAuthMode (optional)
Acceptable authentication modes. This maps to Ceph configura-
tion option "auth_client_required". (Since 3.0)
key-secret: string (optional)
ID of a QCryptoSecret object providing a key for cephx authenti-
cation. This maps to Ceph configuration option "key". (Since
3.0)
server: array of InetSocketAddressBase (optional)
Monitor host address and port. This maps to the "mon_host" Ceph
option.
Since
2.9
ReplicationMode (Enum)
An enumeration of replication modes.
Values
primary
Primary mode, the vm's state will be sent to secondary QEMU.
secondary
Secondary mode, receive the vm's state from primary QEMU.
Since
2.9
If
CONFIG_REPLICATION
BlockdevOptionsReplication (Object)
Driver specific block device options for replication
Members
mode: ReplicationMode
the replication mode
top-id: string (optional)
In secondary mode, node name or device ID of the root node who
owns the replication node chain. Must not be given in primary
mode.
The members of BlockdevOptionsGenericFormat
Since
2.9
If
CONFIG_REPLICATION
NFSTransport (Enum)
An enumeration of NFS transport types
Values
inet TCP transport
Since
2.9
NFSServer (Object)
Captures the address of the socket
Members
type: NFSTransport
transport type used for NFS (only TCP supported)
host: string
host address for NFS server
Since
2.9
BlockdevOptionsNfs (Object)
Driver specific block device option for NFS
Members
server: NFSServer
host address
path: string
path of the image on the host
user: int (optional)
UID value to use when talking to the server (defaults to 65534
on Windows and getuid() on unix)
group: int (optional)
GID value to use when talking to the server (defaults to 65534
on Windows and getgid() in unix)
tcp-syn-count: int (optional)
number of SYNs during the session establishment (defaults to
libnfs default)
readahead-size: int (optional)
set the readahead size in bytes (defaults to libnfs default)
page-cache-size: int (optional)
set the pagecache size in bytes (defaults to libnfs default)
debug: int (optional)
set the NFS debug level (max 2) (defaults to libnfs default)
Since
2.9
BlockdevOptionsCurlBase (Object)
Driver specific block device options shared by all protocols supported
by the curl backend.
Members
url: string
URL of the image file
readahead: int (optional)
Size of the read-ahead cache; must be a multiple of 512 (de-
faults to 256 kB)
timeout: int (optional)
Timeout for connections, in seconds (defaults to 5)
username: string (optional)
Username for authentication (defaults to none)
password-secret: string (optional)
ID of a QCryptoSecret object providing a password for authenti-
cation (defaults to no password)
proxy-username: string (optional)
Username for proxy authentication (defaults to none)
proxy-password-secret: string (optional)
ID of a QCryptoSecret object providing a password for proxy au-
thentication (defaults to no password)
Since
2.9
BlockdevOptionsCurlHttp (Object)
Driver specific block device options for HTTP connections over the curl
backend. URLs must start with "http://".
Members
cookie: string (optional)
List of cookies to set; format is "name1=content1; name2=con-
tent2;" as explained by CURLOPT_COOKIE(3). Defaults to no cook-
ies.
cookie-secret: string (optional)
ID of a QCryptoSecret object providing the cookie data in a se-
cure way. See cookie for the format. (since 2.10)
The members of BlockdevOptionsCurlBase
Since
2.9
BlockdevOptionsCurlHttps (Object)
Driver specific block device options for HTTPS connections over the
curl backend. URLs must start with "https://".
Members
cookie: string (optional)
List of cookies to set; format is "name1=content1; name2=con-
tent2;" as explained by CURLOPT_COOKIE(3). Defaults to no cook-
ies.
sslverify: boolean (optional)
Whether to verify the SSL certificate's validity (defaults to
true)
cookie-secret: string (optional)
ID of a QCryptoSecret object providing the cookie data in a se-
cure way. See cookie for the format. (since 2.10)
The members of BlockdevOptionsCurlBase
Since
2.9
BlockdevOptionsCurlFtp (Object)
Driver specific block device options for FTP connections over the curl
backend. URLs must start with "ftp://".
Members
The members of BlockdevOptionsCurlBase
Since
2.9
BlockdevOptionsCurlFtps (Object)
Driver specific block device options for FTPS connections over the curl
backend. URLs must start with "ftps://".
Members
sslverify: boolean (optional)
Whether to verify the SSL certificate's validity (defaults to
true)
The members of BlockdevOptionsCurlBase
Since
2.9
BlockdevOptionsNbd (Object)
Driver specific block device options for NBD.
Members
server: SocketAddress
NBD server address
export: string (optional)
export name
tls-creds: string (optional)
TLS credentials ID
tls-hostname: string (optional)
TLS hostname override for certificate validation (Since 7.0)
x-dirty-bitmap: string (optional)
A metadata context name such as "qemu:dirty-bitmap:NAME" or
"qemu:allocation-depth" to query in place of the traditional
"base:allocation" block status (see NBD_OPT_LIST_META_CONTEXT in
the NBD protocol; and yes, naming this option x-context would
have made more sense) (since 3.0)
reconnect-delay: int (optional)
On an unexpected disconnect, the nbd client tries to connect
again until succeeding or encountering a serious error. During
the first reconnect-delay seconds, all requests are paused and
will be rerun on a successful reconnect. After that time, any
delayed requests and all future requests before a successful re-
connect will immediately fail. Default 0 (Since 4.2)
open-timeout: int (optional)
In seconds. If zero, the nbd driver tries the connection only
once, and fails to open if the connection fails. If non-zero,
the nbd driver will repeat connection attempts until successful
or until open-timeout seconds have elapsed. Default 0 (Since
7.0)
Features
unstable
Member x-dirty-bitmap is experimental.
Since
2.9
BlockdevOptionsRaw (Object)
Driver specific block device options for the raw driver.
Members
offset: int (optional)
position where the block device starts
size: int (optional)
the assumed size of the device
The members of BlockdevOptionsGenericFormat
Since
2.9
BlockdevOptionsThrottle (Object)
Driver specific block device options for the throttle driver
Members
throttle-group: string
the name of the throttle-group object to use. It must already
exist.
file: BlockdevRef
reference to or definition of the data source block device
Since
2.11
BlockdevOptionsCor (Object)
Driver specific block device options for the copy-on-read driver.
Members
bottom: string (optional)
The name of a non-filter node (allocation-bearing layer) that
limits the COR operations in the backing chain (inclusive), so
that no data below this node will be copied by this filter. If
option is absent, the limit is not applied, so that data from
all backing layers may be copied.
The members of BlockdevOptionsGenericFormat
Since
6.0
OnCbwError (Enum)
An enumeration of possible behaviors for copy-before-write operation
failures.
Values
break-guest-write
report the error to the guest. This way, the guest will not be
able to overwrite areas that cannot be backed up, so the backup
process remains valid.
break-snapshot
continue guest write. Doing so will make the provided snapshot
state invalid and any backup or export process based on it will
finally fail.
Since
7.1
BlockdevOptionsCbw (Object)
Driver specific block device options for the copy-before-write driver,
which does so called copy-before-write operations: when data is written
to the filter, the filter first reads corresponding blocks from its
file child and copies them to target child. After successfully copying,
the write request is propagated to file child. If copying fails, the
original write request is failed too and no data is written to file
child.
Members
target: BlockdevRef
The target for copy-before-write operations.
bitmap: BlockDirtyBitmap (optional)
If specified, copy-before-write filter will do copy-before-write
operations only for dirty regions of the bitmap. Bitmap size
must be equal to length of file and target child of the filter.
Note also, that bitmap is used only to initialize internal bit-
map of the process, so further modifications (or removing) of
specified bitmap doesn't influence the filter. (Since 7.0)
on-cbw-error: OnCbwError (optional)
Behavior on failure of copy-before-write operation. Default is
break-guest-write. (Since 7.1)
cbw-timeout: int (optional)
Zero means no limit. Non-zero sets the timeout in seconds for
copy-before-write operation. When a timeout occurs, the respec-
tive copy-before-write operation will fail, and the on-cbw-error
parameter will decide how this failure is handled. Default 0.
(Since 7.1)
The members of BlockdevOptionsGenericFormat
Since
6.2
BlockdevOptions (Object)
Options for creating a block device. Many options are available for
all block devices, independent of the block driver:
Members
driver: BlockdevDriver
block driver name
node-name: string (optional)
the node name of the new node (Since 2.0). This option is re-
quired on the top level of blockdev-add. Valid node names start
with an alphabetic character and may contain only alphanumeric
characters, '-', '.' and '_'. Their maximum length is 31 charac-
ters.
discard: BlockdevDiscardOptions (optional)
discard-related options (default: ignore)
cache: BlockdevCacheOptions (optional)
cache-related options
read-only: boolean (optional)
whether the block device should be read-only (default: false).
Note that some block drivers support only read-only access, ei-
ther generally or in certain configurations. In this case, the
default value does not work and the option must be specified ex-
plicitly.
auto-read-only: boolean (optional)
if true and read-only is false, QEMU may automatically decide
not to open the image read-write as requested, but fall back to
read-only instead (and switch between the modes later), e.g. de-
pending on whether the image file is writable or whether a writ-
ing user is attached to the node (default: false, since 3.1)
detect-zeroes: BlockdevDetectZeroesOptions (optional)
detect and optimize zero writes (Since 2.1) (default: off)
force-share: boolean (optional)
force share all permission on added nodes. Requires
read-only=true. (Since 2.10)
The members of BlockdevOptionsBlkdebug when driver is "blkdebug"
The members of BlockdevOptionsBlklogwrites when driver is "blklog-
writes"
The members of BlockdevOptionsBlkverify when driver is "blkverify"
The members of BlockdevOptionsBlkreplay when driver is "blkreplay"
The members of BlockdevOptionsGenericFormat when driver is "bochs"
The members of BlockdevOptionsGenericFormat when driver is "cloop"
The members of BlockdevOptionsGenericFormat when driver is "compress"
The members of BlockdevOptionsCbw when driver is "copy-before-write"
The members of BlockdevOptionsCor when driver is "copy-on-read"
The members of BlockdevOptionsGenericFormat when driver is "dmg"
The members of BlockdevOptionsFile when driver is "file"
The members of BlockdevOptionsCurlFtp when driver is "ftp"
The members of BlockdevOptionsCurlFtps when driver is "ftps"
The members of BlockdevOptionsGluster when driver is "gluster"
The members of BlockdevOptionsFile when driver is "host_cdrom" (If:
HAVE_HOST_BLOCK_DEVICE)
The members of BlockdevOptionsFile when driver is "host_device" (If:
HAVE_HOST_BLOCK_DEVICE)
The members of BlockdevOptionsCurlHttp when driver is "http"
The members of BlockdevOptionsCurlHttps when driver is "https"
The members of BlockdevOptionsIoUring when driver is "io_uring" (If:
CONFIG_BLKIO)
The members of BlockdevOptionsIscsi when driver is "iscsi"
The members of BlockdevOptionsLUKS when driver is "luks"
The members of BlockdevOptionsNbd when driver is "nbd"
The members of BlockdevOptionsNfs when driver is "nfs"
The members of BlockdevOptionsNull when driver is "null-aio"
The members of BlockdevOptionsNull when driver is "null-co"
The members of BlockdevOptionsNVMe when driver is "nvme"
The members of BlockdevOptionsNvmeIoUring when driver is "nvme-io_ur-
ing" (If: CONFIG_BLKIO)
The members of BlockdevOptionsGenericFormat when driver is "parallels"
The members of BlockdevOptionsPreallocate when driver is "preallocate"
The members of BlockdevOptionsQcow2 when driver is "qcow2"
The members of BlockdevOptionsQcow when driver is "qcow"
The members of BlockdevOptionsGenericCOWFormat when driver is "qed"
The members of BlockdevOptionsQuorum when driver is "quorum"
The members of BlockdevOptionsRaw when driver is "raw"
The members of BlockdevOptionsRbd when driver is "rbd"
The members of BlockdevOptionsReplication when driver is "replication"
(If: CONFIG_REPLICATION)
The members of BlockdevOptionsGenericFormat when driver is "snap-
shot-access"
The members of BlockdevOptionsSsh when driver is "ssh"
The members of BlockdevOptionsThrottle when driver is "throttle"
The members of BlockdevOptionsGenericFormat when driver is "vdi"
The members of BlockdevOptionsGenericFormat when driver is "vhdx"
The members of BlockdevOptionsVirtioBlkVfioPci when driver is "vir-
tio-blk-vfio-pci" (If: CONFIG_BLKIO)
The members of BlockdevOptionsVirtioBlkVhostUser when driver is "vir-
tio-blk-vhost-user" (If: CONFIG_BLKIO)
The members of BlockdevOptionsVirtioBlkVhostVdpa when driver is "vir-
tio-blk-vhost-vdpa" (If: CONFIG_BLKIO)
The members of BlockdevOptionsGenericCOWFormat when driver is "vmdk"
The members of BlockdevOptionsGenericFormat when driver is "vpc"
The members of BlockdevOptionsVVFAT when driver is "vvfat"
Remaining options are determined by the block driver.
Since
2.9
BlockdevRef (Alternate)
Reference to a block device.
Members
definition: BlockdevOptions
defines a new block device inline
reference: string
references the ID of an existing block device
Since
2.9
BlockdevRefOrNull (Alternate)
Reference to a block device.
Members
definition: BlockdevOptions
defines a new block device inline
reference: string
references the ID of an existing block device. An empty string
means that no block device should be referenced. Deprecated;
use null instead.
null: null
No block device should be referenced (since 2.10)
Since
2.9
blockdev-add (Command)
Creates a new block device.
Arguments
The members of BlockdevOptions
Since
2.9
Example
1.
-> { "execute": "blockdev-add",
"arguments": {
"driver": "qcow2",
"node-name": "test1",
"file": {
"driver": "file",
"filename": "test.qcow2"
}
}
}
<- { "return": {} }
2.
-> { "execute": "blockdev-add",
"arguments": {
"driver": "qcow2",
"node-name": "node0",
"discard": "unmap",
"cache": {
"direct": true
},
"file": {
"driver": "file",
"filename": "/tmp/test.qcow2"
},
"backing": {
"driver": "raw",
"file": {
"driver": "file",
"filename": "/dev/fdset/4"
}
}
}
}
<- { "return": {} }
blockdev-reopen (Command)
Reopens one or more block devices using the given set of options. Any
option not specified will be reset to its default value regardless of
its previous status. If an option cannot be changed or a particular
driver does not support reopening then the command will return an er-
ror. All devices in the list are reopened in one transaction, so if one
of them fails then the whole transaction is cancelled.
The command receives a list of block devices to reopen. For each one of
them, the top-level node-name option (from BlockdevOptions) must be
specified and is used to select the block device to be reopened. Other
node-name options must be either omitted or set to the current name of
the appropriate node. This command won't change any node name and any
attempt to do it will result in an error.
In the case of options that refer to child nodes, the behavior of this
command depends on the value:
1. A set of options (BlockdevOptions): the child is reopened with
the specified set of options.
2. A reference to the current child: the child is reopened using its
existing set of options.
3. A reference to a different node: the current child is replaced
with the specified one.
4. NULL: the current child (if any) is detached.
Options (1) and (2) are supported in all cases. Option (3) is supported
for file and backing, and option (4) for backing only.
Unlike with blockdev-add, the backing option must always be present un-
less the node being reopened does not have a backing file and its image
does not have a default backing file name as part of its metadata.
Arguments
options: array of BlockdevOptions
Not documented
Since
6.1
blockdev-del (Command)
Deletes a block device that has been added using blockdev-add. The
command will fail if the node is attached to a device or is otherwise
being used.
Arguments
node-name: string
Name of the graph node to delete.
Since
2.9
Example
-> { "execute": "blockdev-add",
"arguments": {
"driver": "qcow2",
"node-name": "node0",
"file": {
"driver": "file",
"filename": "test.qcow2"
}
}
}
<- { "return": {} }
-> { "execute": "blockdev-del",
"arguments": { "node-name": "node0" }
}
<- { "return": {} }
BlockdevCreateOptionsFile (Object)
Driver specific image creation options for file.
Members
filename: string
Filename for the new image file
size: int
Size of the virtual disk in bytes
preallocation: PreallocMode (optional)
Preallocation mode for the new image (default: off; allowed val-
ues: off, falloc (if CONFIG_POSIX_FALLOCATE), full (if CON-
FIG_POSIX))
nocow: boolean (optional)
Turn off copy-on-write (valid only on btrfs; default: off)
extent-size-hint: int (optional)
Extent size hint to add to the image file; 0 for not adding an
extent size hint (default: 1 MB, since 5.1)
Since
2.12
BlockdevCreateOptionsGluster (Object)
Driver specific image creation options for gluster.
Members
location: BlockdevOptionsGluster
Where to store the new image file
size: int
Size of the virtual disk in bytes
preallocation: PreallocMode (optional)
Preallocation mode for the new image (default: off; allowed val-
ues: off, falloc (if CONFIG_GLUSTERFS_FALLOCATE), full (if CON-
FIG_GLUSTERFS_ZEROFILL))
Since
2.12
BlockdevCreateOptionsLUKS (Object)
Driver specific image creation options for LUKS.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
preallocation: PreallocMode (optional)
Preallocation mode for the new image (since: 4.2) (default: off;
allowed values: off, metadata, falloc, full)
The members of QCryptoBlockCreateOptionsLUKS
Since
2.12
BlockdevCreateOptionsNfs (Object)
Driver specific image creation options for NFS.
Members
location: BlockdevOptionsNfs
Where to store the new image file
size: int
Size of the virtual disk in bytes
Since
2.12
BlockdevCreateOptionsParallels (Object)
Driver specific image creation options for parallels.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
cluster-size: int (optional)
Cluster size in bytes (default: 1 MB)
Since
2.12
BlockdevCreateOptionsQcow (Object)
Driver specific image creation options for qcow.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
backing-file: string (optional)
File name of the backing file if a backing file should be used
encrypt: QCryptoBlockCreateOptions (optional)
Encryption options if the image should be encrypted
Since
2.12
BlockdevQcow2Version (Enum)
Values
v2 The original QCOW2 format as introduced in qemu 0.10 (version 2)
v3 The extended QCOW2 format as introduced in qemu 1.1 (version 3)
Since
2.12
Qcow2CompressionType (Enum)
Compression type used in qcow2 image file
Values
zlib zlib compression, see <http://zlib.net/>
zstd (If: CONFIG_ZSTD)
zstd compression, see <http://github.com/facebook/zstd>
Since
5.1
BlockdevCreateOptionsQcow2 (Object)
Driver specific image creation options for qcow2.
Members
file: BlockdevRef
Node to create the image format on
data-file: BlockdevRef (optional)
Node to use as an external data file in which all guest data is
stored so that only metadata remains in the qcow2 file (since:
4.0)
data-file-raw: boolean (optional)
True if the external data file must stay valid as a standalone
(read-only) raw image without looking at qcow2 metadata (de-
fault: false; since: 4.0)
extended-l2: boolean (optional)
True to make the image have extended L2 entries (default: false;
since 5.2)
size: int
Size of the virtual disk in bytes
version: BlockdevQcow2Version (optional)
Compatibility level (default: v3)
backing-file: string (optional)
File name of the backing file if a backing file should be used
backing-fmt: BlockdevDriver (optional)
Name of the block driver to use for the backing file
encrypt: QCryptoBlockCreateOptions (optional)
Encryption options if the image should be encrypted
cluster-size: int (optional)
qcow2 cluster size in bytes (default: 65536)
preallocation: PreallocMode (optional)
Preallocation mode for the new image (default: off; allowed val-
ues: off, falloc, full, metadata)
lazy-refcounts: boolean (optional)
True if refcounts may be updated lazily (default: off)
refcount-bits: int (optional)
Width of reference counts in bits (default: 16)
compression-type: Qcow2CompressionType (optional)
The image cluster compression method (default: zlib, since 5.1)
Since
2.12
BlockdevCreateOptionsQed (Object)
Driver specific image creation options for qed.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
backing-file: string (optional)
File name of the backing file if a backing file should be used
backing-fmt: BlockdevDriver (optional)
Name of the block driver to use for the backing file
cluster-size: int (optional)
Cluster size in bytes (default: 65536)
table-size: int (optional)
L1/L2 table size (in clusters)
Since
2.12
BlockdevCreateOptionsRbd (Object)
Driver specific image creation options for rbd/Ceph.
Members
location: BlockdevOptionsRbd
Where to store the new image file. This location cannot point to
a snapshot.
size: int
Size of the virtual disk in bytes
cluster-size: int (optional)
RBD object size
encrypt: RbdEncryptionCreateOptions (optional)
Image encryption options. (Since 6.1)
Since
2.12
BlockdevVmdkSubformat (Enum)
Subformat options for VMDK images
Values
monolithicSparse
Single file image with sparse cluster allocation
monolithicFlat
Single flat data image and a descriptor file
twoGbMaxExtentSparse
Data is split into 2GB (per virtual LBA) sparse extent files, in
addition to a descriptor file
twoGbMaxExtentFlat
Data is split into 2GB (per virtual LBA) flat extent files, in
addition to a descriptor file
streamOptimized
Single file image sparse cluster allocation, optimized for
streaming over network.
Since
4.0
BlockdevVmdkAdapterType (Enum)
Adapter type info for VMDK images
Values
ide Not documented
buslogic
Not documented
lsilogic
Not documented
legacyESX
Not documented
Since
4.0
BlockdevCreateOptionsVmdk (Object)
Driver specific image creation options for VMDK.
Members
file: BlockdevRef
Where to store the new image file. This refers to the image file
for monolithcSparse and streamOptimized format, or the descrip-
tor file for other formats.
size: int
Size of the virtual disk in bytes
extents: array of BlockdevRef (optional)
Where to store the data extents. Required for monolithcFlat,
twoGbMaxExtentSparse and twoGbMaxExtentFlat formats. For mono-
lithicFlat, only one entry is required; for twoGbMaxExtent* for-
mats, the number of entries required is calculated as ex-
tent_number = virtual_size / 2GB. Providing more extents than
will be used is an error.
subformat: BlockdevVmdkSubformat (optional)
The subformat of the VMDK image. Default: "monolithicSparse".
backing-file: string (optional)
The path of backing file. Default: no backing file is used.
adapter-type: BlockdevVmdkAdapterType (optional)
The adapter type used to fill in the descriptor. Default: ide.
hwversion: string (optional)
Hardware version. The meaningful options are "4" or "6". De-
fault: "4".
toolsversion: string (optional)
VMware guest tools version. Default: "2147483647" (Since 6.2)
zeroed-grain: boolean (optional)
Whether to enable zeroed-grain feature for sparse subformats.
Default: false.
Since
4.0
BlockdevCreateOptionsSsh (Object)
Driver specific image creation options for SSH.
Members
location: BlockdevOptionsSsh
Where to store the new image file
size: int
Size of the virtual disk in bytes
Since
2.12
BlockdevCreateOptionsVdi (Object)
Driver specific image creation options for VDI.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
preallocation: PreallocMode (optional)
Preallocation mode for the new image (default: off; allowed val-
ues: off, metadata)
Since
2.12
BlockdevVhdxSubformat (Enum)
Values
dynamic
Growing image file
fixed Preallocated fixed-size image file
Since
2.12
BlockdevCreateOptionsVhdx (Object)
Driver specific image creation options for vhdx.
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
log-size: int (optional)
Log size in bytes, must be a multiple of 1 MB (default: 1 MB)
block-size: int (optional)
Block size in bytes, must be a multiple of 1 MB and not larger
than 256 MB (default: automatically choose a block size depend-
ing on the image size)
subformat: BlockdevVhdxSubformat (optional)
vhdx subformat (default: dynamic)
block-state-zero: boolean (optional)
Force use of payload blocks of type 'ZERO'. Non-standard, but
default. Do not set to 'off' when using 'qemu-img convert' with
subformat=dynamic.
Since
2.12
BlockdevVpcSubformat (Enum)
Values
dynamic
Growing image file
fixed Preallocated fixed-size image file
Since
2.12
BlockdevCreateOptionsVpc (Object)
Driver specific image creation options for vpc (VHD).
Members
file: BlockdevRef
Node to create the image format on
size: int
Size of the virtual disk in bytes
subformat: BlockdevVpcSubformat (optional)
vhdx subformat (default: dynamic)
force-size: boolean (optional)
Force use of the exact byte size instead of rounding to the next
size that can be represented in CHS geometry (default: false)
Since
2.12
BlockdevCreateOptions (Object)
Options for creating an image format on a given node.
Members
driver: BlockdevDriver
block driver to create the image format
The members of BlockdevCreateOptionsFile when driver is "file"
The members of BlockdevCreateOptionsGluster when driver is "gluster"
The members of BlockdevCreateOptionsLUKS when driver is "luks"
The members of BlockdevCreateOptionsNfs when driver is "nfs"
The members of BlockdevCreateOptionsParallels when driver is "paral-
lels"
The members of BlockdevCreateOptionsQcow when driver is "qcow"
The members of BlockdevCreateOptionsQcow2 when driver is "qcow2"
The members of BlockdevCreateOptionsQed when driver is "qed"
The members of BlockdevCreateOptionsRbd when driver is "rbd"
The members of BlockdevCreateOptionsSsh when driver is "ssh"
The members of BlockdevCreateOptionsVdi when driver is "vdi"
The members of BlockdevCreateOptionsVhdx when driver is "vhdx"
The members of BlockdevCreateOptionsVmdk when driver is "vmdk"
The members of BlockdevCreateOptionsVpc when driver is "vpc"
Since
2.12
blockdev-create (Command)
Starts a job to create an image format on a given node. The job is au-
tomatically finalized, but a manual job-dismiss is required.
Arguments
job-id: string
Identifier for the newly created job.
options: BlockdevCreateOptions
Options for the image creation.
Since
3.0
BlockdevAmendOptionsLUKS (Object)
Driver specific image amend options for LUKS.
Members
The members of QCryptoBlockAmendOptionsLUKS
Since
5.1
BlockdevAmendOptionsQcow2 (Object)
Driver specific image amend options for qcow2. For now, only encryp-
tion options can be amended
encrypt Encryption options to be amended
Members
encrypt: QCryptoBlockAmendOptions (optional)
Not documented
Since
5.1
BlockdevAmendOptions (Object)
Options for amending an image format
Members
driver: BlockdevDriver
Block driver of the node to amend.
The members of BlockdevAmendOptionsLUKS when driver is "luks"
The members of BlockdevAmendOptionsQcow2 when driver is "qcow2"
Since
5.1
x-blockdev-amend (Command)
Starts a job to amend format specific options of an existing open block
device The job is automatically finalized, but a manual job-dismiss is
required.
Arguments
job-id: string
Identifier for the newly created job.
node-name: string
Name of the block node to work on
options: BlockdevAmendOptions
Options (driver specific)
force: boolean (optional)
Allow unsafe operations, format specific For luks that allows
erase of the last active keyslot (permanent loss of data), and
replacement of an active keyslot (possible loss of data if IO
error happens)
Features
unstable
This command is experimental.
Since
5.1
BlockErrorAction (Enum)
An enumeration of action that has been taken when a DISK I/O occurs
Values
ignore error has been ignored
report error has been reported to the device
stop error caused VM to be stopped
Since
2.1
BLOCK_IMAGE_CORRUPTED (Event)
Emitted when a disk image is being marked corrupt. The image can be
identified by its device or node name. The 'device' field is always
present for compatibility reasons, but it can be empty ("") if the im-
age does not have a device name associated.
Arguments
device: string
device name. This is always present for compatibility reasons,
but it can be empty ("") if the image does not have a device
name associated.
node-name: string (optional)
node name (Since: 2.4)
msg: string
informative message for human consumption, such as the kind of
corruption being detected. It should not be parsed by machine as
it is not guaranteed to be stable
offset: int (optional)
if the corruption resulted from an image access, this is the
host's access offset into the image
size: int (optional)
if the corruption resulted from an image access, this is the ac-
cess size
fatal: boolean
if set, the image is marked corrupt and therefore unusable after
this event and must be repaired (Since 2.2; before, every
BLOCK_IMAGE_CORRUPTED event was fatal)
Note
If action is "stop", a STOP event will eventually follow the
BLOCK_IO_ERROR event.
Example
<- { "event": "BLOCK_IMAGE_CORRUPTED",
"data": { "device": "", "node-name": "drive", "fatal": false,
"msg": "L2 table offset 0x2a2a2a00 unaligned (L1 index: 0)" },
"timestamp": { "seconds": 1648243240, "microseconds": 906060 } }
Since
1.7
BLOCK_IO_ERROR (Event)
Emitted when a disk I/O error occurs
Arguments
device: string
device name. This is always present for compatibility reasons,
but it can be empty ("") if the image does not have a device
name associated.
node-name: string (optional)
node name. Note that errors may be reported for the root node
that is directly attached to a guest device rather than for the
node where the error occurred. The node name is not present if
the drive is empty. (Since: 2.8)
operation: IoOperationType
I/O operation
action: BlockErrorAction
action that has been taken
nospace: boolean (optional)
true if I/O error was caused due to a no-space condition. This
key is only present if query-block's io-status is present,
please see query-block documentation for more information
(since: 2.2)
reason: string
human readable string describing the error cause. (This field
is a debugging aid for humans, it should not be parsed by appli-
cations) (since: 2.2)
Note
If action is "stop", a STOP event will eventually follow the
BLOCK_IO_ERROR event
Since
0.13
Example
<- { "event": "BLOCK_IO_ERROR",
"data": { "device": "ide0-hd1",
"node-name": "#block212",
"operation": "write",
"action": "stop",
"reason": "No space left on device" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
BLOCK_JOB_COMPLETED (Event)
Emitted when a block job has completed
Arguments
type: JobType
job type
device: string
The job identifier. Originally the device name but other values
are allowed since QEMU 2.7
len: int
maximum progress value
offset: int
current progress value. On success this is equal to len. On
failure this is less than len
speed: int
rate limit, bytes per second
error: string (optional)
error message. Only present on failure. This field contains a
human-readable error message. There are no semantics other than
that streaming has failed and clients should not try to inter-
pret the error string
Since
1.1
Example
<- { "event": "BLOCK_JOB_COMPLETED",
"data": { "type": "stream", "device": "virtio-disk0",
"len": 10737418240, "offset": 10737418240,
"speed": 0 },
"timestamp": { "seconds": 1267061043, "microseconds": 959568 } }
BLOCK_JOB_CANCELLED (Event)
Emitted when a block job has been cancelled
Arguments
type: JobType
job type
device: string
The job identifier. Originally the device name but other values
are allowed since QEMU 2.7
len: int
maximum progress value
offset: int
current progress value. On success this is equal to len. On
failure this is less than len
speed: int
rate limit, bytes per second
Since
1.1
Example
<- { "event": "BLOCK_JOB_CANCELLED",
"data": { "type": "stream", "device": "virtio-disk0",
"len": 10737418240, "offset": 134217728,
"speed": 0 },
"timestamp": { "seconds": 1267061043, "microseconds": 959568 } }
BLOCK_JOB_ERROR (Event)
Emitted when a block job encounters an error
Arguments
device: string
The job identifier. Originally the device name but other values
are allowed since QEMU 2.7
operation: IoOperationType
I/O operation
action: BlockErrorAction
action that has been taken
Since
1.3
Example
<- { "event": "BLOCK_JOB_ERROR",
"data": { "device": "ide0-hd1",
"operation": "write",
"action": "stop" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
BLOCK_JOB_READY (Event)
Emitted when a block job is ready to complete
Arguments
type: JobType
job type
device: string
The job identifier. Originally the device name but other values
are allowed since QEMU 2.7
len: int
maximum progress value
offset: int
current progress value. On success this is equal to len. On
failure this is less than len
speed: int
rate limit, bytes per second
Note
The "ready to complete" status is always reset by a BLOCK_JOB_ERROR
event
Since
1.3
Example
<- { "event": "BLOCK_JOB_READY",
"data": { "device": "drive0", "type": "mirror", "speed": 0,
"len": 2097152, "offset": 2097152 },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
BLOCK_JOB_PENDING (Event)
Emitted when a block job is awaiting explicit authorization to finalize
graph changes via block-job-finalize. If this job is part of a transac-
tion, it will not emit this event until the transaction has converged
first.
Arguments
type: JobType
job type
id: string
The job identifier.
Since
2.12
Example
<- { "event": "BLOCK_JOB_PENDING",
"data": { "type": "mirror", "id": "backup_1" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
PreallocMode (Enum)
Preallocation mode of QEMU image file
Values
off no preallocation
metadata
preallocate only for metadata
falloc like full preallocation but allocate disk space by posix_fallo-
cate() rather than writing data.
full preallocate all data by writing it to the device to ensure disk
space is really available. This data may or may not be zero, de-
pending on the image format and storage. full preallocation
also sets up metadata correctly.
Since
2.2
BLOCK_WRITE_THRESHOLD (Event)
Emitted when writes on block device reaches or exceeds the configured
write threshold. For thin-provisioned devices, this means the device
should be extended to avoid pausing for disk exhaustion. The event is
one shot. Once triggered, it needs to be re-registered with another
block-set-write-threshold command.
Arguments
node-name: string
graph node name on which the threshold was exceeded.
amount-exceeded: int
amount of data which exceeded the threshold, in bytes.
write-threshold: int
last configured threshold, in bytes.
Since
2.3
block-set-write-threshold (Command)
Change the write threshold for a block drive. An event will be deliv-
ered if a write to this block drive crosses the configured threshold.
The threshold is an offset, thus must be non-negative. Default is no
write threshold. Setting the threshold to zero disables it.
This is useful to transparently resize thin-provisioned drives without
the guest OS noticing.
Arguments
node-name: string
graph node name on which the threshold must be set.
write-threshold: int
configured threshold for the block device, bytes. Use 0 to dis-
able the threshold.
Since
2.3
Example
-> { "execute": "block-set-write-threshold",
"arguments": { "node-name": "mydev",
"write-threshold": 17179869184 } }
<- { "return": {} }
x-blockdev-change (Command)
Dynamically reconfigure the block driver state graph. It can be used to
add, remove, insert or replace a graph node. Currently only the Quorum
driver implements this feature to add or remove its child. This is use-
ful to fix a broken quorum child.
If node is specified, it will be inserted under parent. child may not
be specified in this case. If both parent and child are specified but
node is not, child will be detached from parent.
Arguments
parent: string
the id or name of the parent node.
child: string (optional)
the name of a child under the given parent node.
node: string (optional)
the name of the node that will be added.
Features
unstable
This command is experimental, and its API is not stable. It
does not support all kinds of operations, all kinds of children,
nor all block drivers.
FIXME Removing children from a quorum node means introducing
gaps in the child indices. This cannot be represented in the
'children' list of BlockdevOptionsQuorum, as returned by
.bdrv_refresh_filename().
Warning: The data in a new quorum child MUST be consistent with
that of the rest of the array.
Since
2.7
Example
1. Add a new node to a quorum
-> { "execute": "blockdev-add",
"arguments": {
"driver": "raw",
"node-name": "new_node",
"file": { "driver": "file",
"filename": "test.raw" } } }
<- { "return": {} }
-> { "execute": "x-blockdev-change",
"arguments": { "parent": "disk1",
"node": "new_node" } }
<- { "return": {} }
2. Delete a quorum's node
-> { "execute": "x-blockdev-change",
"arguments": { "parent": "disk1",
"child": "children.1" } }
<- { "return": {} }
x-blockdev-set-iothread (Command)
Move node and its children into the iothread. If iothread is null then
move node and its children into the main loop.
The node must not be attached to a BlockBackend.
Arguments
node-name: string
the name of the block driver node
iothread: StrOrNull
the name of the IOThread object or null for the main loop
force: boolean (optional)
true if the node and its children should be moved when a Block-
Backend is already attached
Features
unstable
This command is experimental and intended for test cases that
need control over IOThreads only.
Since
2.12
Example
1. Move a node into an IOThread
-> { "execute": "x-blockdev-set-iothread",
"arguments": { "node-name": "disk1",
"iothread": "iothread0" } }
<- { "return": {} }
2. Move a node into the main loop
-> { "execute": "x-blockdev-set-iothread",
"arguments": { "node-name": "disk1",
"iothread": null } }
<- { "return": {} }
QuorumOpType (Enum)
An enumeration of the quorum operation types
Values
read read operation
write write operation
flush flush operation
Since
2.6
QUORUM_FAILURE (Event)
Emitted by the Quorum block driver if it fails to establish a quorum
Arguments
reference: string
device name if defined else node name
sector-num: int
number of the first sector of the failed read operation
sectors-count: int
failed read operation sector count
Note
This event is rate-limited.
Since
2.0
Example
<- { "event": "QUORUM_FAILURE",
"data": { "reference": "usr1", "sector-num": 345435, "sectors-count": 5 },
"timestamp": { "seconds": 1344522075, "microseconds": 745528 } }
QUORUM_REPORT_BAD (Event)
Emitted to report a corruption of a Quorum file
Arguments
type: QuorumOpType
quorum operation type (Since 2.6)
error: string (optional)
error message. Only present on failure. This field contains a
human-readable error message. There are no semantics other than
that the block layer reported an error and clients should not
try to interpret the error string.
node-name: string
the graph node name of the block driver state
sector-num: int
number of the first sector of the failed read operation
sectors-count: int
failed read operation sector count
Note
This event is rate-limited.
Since
2.0
Example
1. Read operation
{ "event": "QUORUM_REPORT_BAD",
"data": { "node-name": "node0", "sector-num": 345435, "sectors-count": 5,
"type": "read" },
"timestamp": { "seconds": 1344522075, "microseconds": 745528 } }
2. Flush operation
{ "event": "QUORUM_REPORT_BAD",
"data": { "node-name": "node0", "sector-num": 0, "sectors-count": 2097120,
"type": "flush", "error": "Broken pipe" },
"timestamp": { "seconds": 1456406829, "microseconds": 291763 } }
BlockdevSnapshotInternal (Object)
Members
device: string
the device name or node-name of a root node to generate the
snapshot from
name: string
the name of the internal snapshot to be created
Notes
In transaction, if name is empty, or any snapshot matching name exists,
the operation will fail. Only some image formats support it, for exam-
ple, qcow2, and rbd.
Since
1.7
blockdev-snapshot-internal-sync (Command)
Synchronously take an internal snapshot of a block device, when the
format of the image used supports it. If the name is an empty string,
or a snapshot with name already exists, the operation will fail.
For the arguments, see the documentation of BlockdevSnapshotInternal.
Returns
• nothing on success
• If device is not a valid block device, GenericError
• If any snapshot matching name exists, or name is empty, GenericError
• If the format of the image used does not support it, BlockFormatFea-
tureNotSupported
Since
1.7
Example
-> { "execute": "blockdev-snapshot-internal-sync",
"arguments": { "device": "ide-hd0",
"name": "snapshot0" }
}
<- { "return": {} }
blockdev-snapshot-delete-internal-sync (Command)
Synchronously delete an internal snapshot of a block device, when the
format of the image used support it. The snapshot is identified by name
or id or both. One of the name or id is required. Return SnapshotInfo
for the successfully deleted snapshot.
Arguments
device: string
the device name or node-name of a root node to delete the snap-
shot from
id: string (optional)
optional the snapshot's ID to be deleted
name: string (optional)
optional the snapshot's name to be deleted
Returns
• SnapshotInfo on success
• If device is not a valid block device, GenericError
• If snapshot not found, GenericError
• If the format of the image used does not support it, BlockFormatFea-
tureNotSupported
• If id and name are both not specified, GenericError
Since
1.7
Example
-> { "execute": "blockdev-snapshot-delete-internal-sync",
"arguments": { "device": "ide-hd0",
"name": "snapshot0" }
}
<- { "return": {
"id": "1",
"name": "snapshot0",
"vm-state-size": 0,
"date-sec": 1000012,
"date-nsec": 10,
"vm-clock-sec": 100,
"vm-clock-nsec": 20,
"icount": 220414
}
}
Additional block stuff (VM related)
BiosAtaTranslation (Enum)
Policy that BIOS should use to interpret cylinder/head/sector ad-
dresses. Note that Bochs BIOS and SeaBIOS will not actually translate
logical CHS to physical; instead, they will use logical block address-
ing.
Values
auto If cylinder/heads/sizes are passed, choose between none and LBA
depending on the size of the disk. If they are not passed,
choose none if QEMU can guess that the disk had 16 or fewer
heads, large if QEMU can guess that the disk had 131072 or fewer
tracks across all heads (i.e. cylinders*heads<131072), otherwise
LBA.
none The physical disk geometry is equal to the logical geometry.
lba Assume 63 sectors per track and one of 16, 32, 64, 128 or 255
heads (if fewer than 255 are enough to cover the whole disk with
1024 cylinders/head). The number of cylinders/head is then com-
puted based on the number of sectors and heads.
large The number of cylinders per head is scaled down to 1024 by cor-
respondingly scaling up the number of heads.
rechs Same as large, but first convert a 16-head geometry to 15-head,
by proportionally scaling up the number of cylinders/head.
Since
2.0
FloppyDriveType (Enum)
Type of Floppy drive to be emulated by the Floppy Disk Controller.
Values
144 1.44MB 3.5" drive
288 2.88MB 3.5" drive
120 1.2MB 5.25" drive
none No drive connected
auto Automatically determined by inserted media at boot
Since
2.6
PRManagerInfo (Object)
Information about a persistent reservation manager
Members
id: string
the identifier of the persistent reservation manager
connected: boolean
true if the persistent reservation manager is connected to the
underlying storage or helper
Since
3.0
query-pr-managers (Command)
Returns a list of information about each persistent reservation man-
ager.
Returns
a list of PRManagerInfo for each persistent reservation manager
Since
3.0
eject (Command)
Ejects the medium from a removable drive.
Arguments
device: string (optional)
Block device name
id: string (optional)
The name or QOM path of the guest device (since: 2.8)
force: boolean (optional)
If true, eject regardless of whether the drive is locked. If
not specified, the default value is false.
Features
deprecated
Member device is deprecated. Use id instead.
Returns
• Nothing on success
• If device is not a valid block device, DeviceNotFound
Notes
Ejecting a device with no media results in success
Since
0.14
Example
-> { "execute": "eject", "arguments": { "id": "ide1-0-1" } }
<- { "return": {} }
blockdev-open-tray (Command)
Opens a block device's tray. If there is a block driver state tree in-
serted as a medium, it will become inaccessible to the guest (but it
will remain associated to the block device, so closing the tray will
make it accessible again).
If the tray was already open before, this will be a no-op.
Once the tray opens, a DEVICE_TRAY_MOVED event is emitted. There are
cases in which no such event will be generated, these include:
• if the guest has locked the tray, force is false and the guest does
not respond to the eject request
• if the BlockBackend denoted by device does not have a guest device
attached to it
• if the guest device does not have an actual tray
Arguments
device: string (optional)
Block device name
id: string (optional)
The name or QOM path of the guest device (since: 2.8)
force: boolean (optional)
if false (the default), an eject request will be sent to the
guest if it has locked the tray (and the tray will not be opened
immediately); if true, the tray will be opened regardless of
whether it is locked
Features
deprecated
Member device is deprecated. Use id instead.
Since
2.5
Example
-> { "execute": "blockdev-open-tray",
"arguments": { "id": "ide0-1-0" } }
<- { "timestamp": { "seconds": 1418751016,
"microseconds": 716996 },
"event": "DEVICE_TRAY_MOVED",
"data": { "device": "ide1-cd0",
"id": "ide0-1-0",
"tray-open": true } }
<- { "return": {} }
blockdev-close-tray (Command)
Closes a block device's tray. If there is a block driver state tree as-
sociated with the block device (which is currently ejected), that tree
will be loaded as the medium.
If the tray was already closed before, this will be a no-op.
Arguments
device: string (optional)
Block device name
id: string (optional)
The name or QOM path of the guest device (since: 2.8)
Features
deprecated
Member device is deprecated. Use id instead.
Since
2.5
Example
-> { "execute": "blockdev-close-tray",
"arguments": { "id": "ide0-1-0" } }
<- { "timestamp": { "seconds": 1418751345,
"microseconds": 272147 },
"event": "DEVICE_TRAY_MOVED",
"data": { "device": "ide1-cd0",
"id": "ide0-1-0",
"tray-open": false } }
<- { "return": {} }
blockdev-remove-medium (Command)
Removes a medium (a block driver state tree) from a block device. That
block device's tray must currently be open (unless there is no attached
guest device).
If the tray is open and there is no medium inserted, this will be a
no-op.
Arguments
id: string
The name or QOM path of the guest device
Since
2.12
Example
-> { "execute": "blockdev-remove-medium",
"arguments": { "id": "ide0-1-0" } }
<- { "error": { "class": "GenericError",
"desc": "Tray of device 'ide0-1-0' is not open" } }
-> { "execute": "blockdev-open-tray",
"arguments": { "id": "ide0-1-0" } }
<- { "timestamp": { "seconds": 1418751627,
"microseconds": 549958 },
"event": "DEVICE_TRAY_MOVED",
"data": { "device": "ide1-cd0",
"id": "ide0-1-0",
"tray-open": true } }
<- { "return": {} }
-> { "execute": "blockdev-remove-medium",
"arguments": { "id": "ide0-1-0" } }
<- { "return": {} }
blockdev-insert-medium (Command)
Inserts a medium (a block driver state tree) into a block device. That
block device's tray must currently be open (unless there is no attached
guest device) and there must be no medium inserted already.
Arguments
id: string
The name or QOM path of the guest device
node-name: string
name of a node in the block driver state graph
Since
2.12
Example
-> { "execute": "blockdev-add",
"arguments": {
"node-name": "node0",
"driver": "raw",
"file": { "driver": "file",
"filename": "fedora.iso" } } }
<- { "return": {} }
-> { "execute": "blockdev-insert-medium",
"arguments": { "id": "ide0-1-0",
"node-name": "node0" } }
<- { "return": {} }
BlockdevChangeReadOnlyMode (Enum)
Specifies the new read-only mode of a block device subject to the
blockdev-change-medium command.
Values
retain Retains the current read-only mode
read-only
Makes the device read-only
read-write
Makes the device writable
Since
2.3
blockdev-change-medium (Command)
Changes the medium inserted into a block device by ejecting the current
medium and loading a new image file which is inserted as the new medium
(this command combines blockdev-open-tray, blockdev-remove-medium,
blockdev-insert-medium and blockdev-close-tray).
Arguments
device: string (optional)
Block device name
id: string (optional)
The name or QOM path of the guest device (since: 2.8)
filename: string
filename of the new image to be loaded
format: string (optional)
format to open the new image with (defaults to the probed for-
mat)
read-only-mode: BlockdevChangeReadOnlyMode (optional)
change the read-only mode of the device; defaults to 'retain'
force: boolean (optional)
if false (the default), an eject request through block-
dev-open-tray will be sent to the guest if it has locked the
tray (and the tray will not be opened immediately); if true, the
tray will be opened regardless of whether it is locked. (since
7.1)
Features
deprecated
Member device is deprecated. Use id instead.
Since
2.5
Examples
1. Change a removable medium
-> { "execute": "blockdev-change-medium",
"arguments": { "id": "ide0-1-0",
"filename": "/srv/images/Fedora-12-x86_64-DVD.iso",
"format": "raw" } }
<- { "return": {} }
2. Load a read-only medium into a writable drive
-> { "execute": "blockdev-change-medium",
"arguments": { "id": "floppyA",
"filename": "/srv/images/ro.img",
"format": "raw",
"read-only-mode": "retain" } }
<- { "error":
{ "class": "GenericError",
"desc": "Could not open '/srv/images/ro.img': Permission denied" } }
-> { "execute": "blockdev-change-medium",
"arguments": { "id": "floppyA",
"filename": "/srv/images/ro.img",
"format": "raw",
"read-only-mode": "read-only" } }
<- { "return": {} }
DEVICE_TRAY_MOVED (Event)
Emitted whenever the tray of a removable device is moved by the guest
or by HMP/QMP commands
Arguments
device: string
Block device name. This is always present for compatibility rea-
sons, but it can be empty ("") if the image does not have a de-
vice name associated.
id: string
The name or QOM path of the guest device (since 2.8)
tray-open: boolean
true if the tray has been opened or false if it has been closed
Since
1.1
Example
<- { "event": "DEVICE_TRAY_MOVED",
"data": { "device": "ide1-cd0",
"id": "/machine/unattached/device[22]",
"tray-open": true
},
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
PR_MANAGER_STATUS_CHANGED (Event)
Emitted whenever the connected status of a persistent reservation man-
ager changes.
Arguments
id: string
The id of the PR manager object
connected: boolean
true if the PR manager is connected to a backend
Since
3.0
Example
<- { "event": "PR_MANAGER_STATUS_CHANGED",
"data": { "id": "pr-helper0",
"connected": true
},
"timestamp": { "seconds": 1519840375, "microseconds": 450486 } }
block_set_io_throttle (Command)
Change I/O throttle limits for a block drive.
Since QEMU 2.4, each device with I/O limits is member of a throttle
group.
If two or more devices are members of the same group, the limits will
apply to the combined I/O of the whole group in a round-robin fashion.
Therefore, setting new I/O limits to a device will affect the whole
group.
The name of the group can be specified using the 'group' parameter. If
the parameter is unset, it is assumed to be the current group of that
device. If it's not in any group yet, the name of the device will be
used as the name for its group.
The 'group' parameter can also be used to move a device to a different
group. In this case the limits specified in the parameters will be ap-
plied to the new group only.
I/O limits can be disabled by setting all of them to 0. In this case
the device will be removed from its group and the rest of its members
will not be affected. The 'group' parameter is ignored.
Arguments
The members of BlockIOThrottle
Returns
• Nothing on success
• If device is not a valid block device, DeviceNotFound
Since
1.1
Example
-> { "execute": "block_set_io_throttle",
"arguments": { "id": "virtio-blk-pci0/virtio-backend",
"bps": 0,
"bps_rd": 0,
"bps_wr": 0,
"iops": 512,
"iops_rd": 0,
"iops_wr": 0,
"bps_max": 0,
"bps_rd_max": 0,
"bps_wr_max": 0,
"iops_max": 0,
"iops_rd_max": 0,
"iops_wr_max": 0,
"bps_max_length": 0,
"iops_size": 0 } }
<- { "return": {} }
-> { "execute": "block_set_io_throttle",
"arguments": { "id": "ide0-1-0",
"bps": 1000000,
"bps_rd": 0,
"bps_wr": 0,
"iops": 0,
"iops_rd": 0,
"iops_wr": 0,
"bps_max": 8000000,
"bps_rd_max": 0,
"bps_wr_max": 0,
"iops_max": 0,
"iops_rd_max": 0,
"iops_wr_max": 0,
"bps_max_length": 60,
"iops_size": 0 } }
<- { "return": {} }
block-latency-histogram-set (Command)
Manage read, write and flush latency histograms for the device.
If only id parameter is specified, remove all present latency his-
tograms for the device. Otherwise, add/reset some of (or all) latency
histograms.
Arguments
id: string
The name or QOM path of the guest device.
boundaries: array of int (optional)
list of interval boundary values (see description in BlockLaten-
cyHistogramInfo definition). If specified, all latency his-
tograms are removed, and empty ones created for all io types
with intervals corresponding to boundaries (except for io types,
for which specific boundaries are set through the following pa-
rameters).
boundaries-read: array of int (optional)
list of interval boundary values for read latency histogram. If
specified, old read latency histogram is removed, and empty one
created with intervals corresponding to boundaries-read. The pa-
rameter has higher priority then boundaries.
boundaries-write: array of int (optional)
list of interval boundary values for write latency histogram.
boundaries-flush: array of int (optional)
list of interval boundary values for flush latency histogram.
Returns
error if device is not found or any boundary arrays are invalid.
Since
4.0
Example
set new histograms for all io types with intervals
[0, 10), [10, 50), [50, 100), [100, +inf):
-> { "execute": "block-latency-histogram-set",
"arguments": { "id": "drive0",
"boundaries": [10, 50, 100] } }
<- { "return": {} }
Example
set new histogram only for write, other histograms will remain
not changed (or not created):
-> { "execute": "block-latency-histogram-set",
"arguments": { "id": "drive0",
"boundaries-write": [10, 50, 100] } }
<- { "return": {} }
Example
set new histograms with the following intervals:
read, flush: [0, 10), [10, 50), [50, 100), [100, +inf)
write: [0, 1000), [1000, 5000), [5000, +inf)
-> { "execute": "block-latency-histogram-set",
"arguments": { "id": "drive0",
"boundaries": [10, 50, 100],
"boundaries-write": [1000, 5000] } }
<- { "return": {} }
Example
remove all latency histograms:
-> { "execute": "block-latency-histogram-set",
"arguments": { "id": "drive0" } }
<- { "return": {} }
Block device exports
NbdServerOptions (Object)
Keep this type consistent with the nbd-server-start arguments. The only
intended difference is using SocketAddress instead of SocketAddressLe-
gacy.
Members
addr: SocketAddress
Address on which to listen.
tls-creds: string (optional)
ID of the TLS credentials object (since 2.6).
tls-authz: string (optional)
ID of the QAuthZ authorization object used to validate the
client's x509 distinguished name. This object is is only re-
solved at time of use, so can be deleted and recreated on the
fly while the NBD server is active. If missing, it will default
to denying access (since 4.0).
max-connections: int (optional)
The maximum number of connections to allow at the same time, 0
for unlimited. Setting this to 1 also stops the server from ad-
vertising multiple client support (since 5.2; default: 0)
Since
4.2
nbd-server-start (Command)
Start an NBD server listening on the given host and port. Block de-
vices can then be exported using nbd-server-add. The NBD server will
present them as named exports; for example, another QEMU instance could
refer to them as "nbd:HOST:PORT:exportname=NAME".
Keep this type consistent with the NbdServerOptions type. The only in-
tended difference is using SocketAddressLegacy instead of SocketAd-
dress.
Arguments
addr: SocketAddressLegacy
Address on which to listen.
tls-creds: string (optional)
ID of the TLS credentials object (since 2.6).
tls-authz: string (optional)
ID of the QAuthZ authorization object used to validate the
client's x509 distinguished name. This object is is only re-
solved at time of use, so can be deleted and recreated on the
fly while the NBD server is active. If missing, it will default
to denying access (since 4.0).
max-connections: int (optional)
The maximum number of connections to allow at the same time, 0
for unlimited. Setting this to 1 also stops the server from ad-
vertising multiple client support (since 5.2; default: 0).
Returns
error if the server is already running.
Since
1.3
BlockExportOptionsNbdBase (Object)
An NBD block export (common options shared between nbd-server-add and
the NBD branch of block-export-add).
Members
name: string (optional)
Export name. If unspecified, the device parameter is used as the
export name. (Since 2.12)
description: string (optional)
Free-form description of the export, up to 4096 bytes. (Since
5.0)
Since
5.0
BlockExportOptionsNbd (Object)
An NBD block export (distinct options used in the NBD branch of
block-export-add).
Members
bitmaps: array of BlockDirtyBitmapOrStr (optional)
Also export each of the named dirty bitmaps reachable from de-
vice, so the NBD client can use NBD_OPT_SET_META_CONTEXT with
the metadata context name "qemu:dirty-bitmap:BITMAP" to inspect
each bitmap. Since 7.1 bitmap may be specified by node/name
pair.
allocation-depth: boolean (optional)
Also export the allocation depth map for device, so the NBD
client can use NBD_OPT_SET_META_CONTEXT with the metadata con-
text name "qemu:allocation-depth" to inspect allocation details.
(since 5.2)
The members of BlockExportOptionsNbdBase
Since
5.2
BlockExportOptionsVhostUserBlk (Object)
A vhost-user-blk block export.
Members
addr: SocketAddress
The vhost-user socket on which to listen. Both 'unix' and 'fd'
SocketAddress types are supported. Passed fds must be UNIX do-
main sockets.
logical-block-size: int (optional)
Logical block size in bytes. Defaults to 512 bytes.
num-queues: int (optional)
Number of request virtqueues. Must be greater than 0. Defaults
to 1.
Since
5.2
FuseExportAllowOther (Enum)
Possible allow_other modes for FUSE exports.
Values
off Do not pass allow_other as a mount option.
on Pass allow_other as a mount option.
auto Try mounting with allow_other first, and if that fails, retry
without allow_other.
Since
6.1
BlockExportOptionsFuse (Object)
Options for exporting a block graph node on some (file) mountpoint as a
raw image.
Members
mountpoint: string
Path on which to export the block device via FUSE. This must
point to an existing regular file.
growable: boolean (optional)
Whether writes beyond the EOF should grow the block node accord-
ingly. (default: false)
allow-other: FuseExportAllowOther (optional)
If this is off, only qemu's user is allowed access to this ex-
port. That cannot be changed even with chmod or chown. En-
abling this option will allow other users access to the export
with the FUSE mount option "allow_other". Note that using al-
low_other as a non-root user requires user_allow_other to be en-
abled in the global fuse.conf configuration file. In auto mode
(the default), the FUSE export driver will first attempt to
mount the export with allow_other, and if that fails, try again
without. (since 6.1; default: auto)
Since
6.0
If
CONFIG_FUSE
BlockExportOptionsVduseBlk (Object)
A vduse-blk block export.
Members
name: string
the name of VDUSE device (must be unique across the host).
num-queues: int (optional)
the number of virtqueues. Defaults to 1.
queue-size: int (optional)
the size of virtqueue. Defaults to 256.
logical-block-size: int (optional)
Logical block size in bytes. Range [512, PAGE_SIZE] and must be
power of 2. Defaults to 512 bytes.
serial: string (optional)
the serial number of virtio block device. Defaults to empty
string.
Since
7.1
NbdServerAddOptions (Object)
An NBD block export, per legacy nbd-server-add command.
Members
device: string
The device name or node name of the node to be exported
writable: boolean (optional)
Whether clients should be able to write to the device via the
NBD connection (default false).
bitmap: string (optional)
Also export a single dirty bitmap reachable from device, so the
NBD client can use NBD_OPT_SET_META_CONTEXT with the metadata
context name "qemu:dirty-bitmap:BITMAP" to inspect the bitmap
(since 4.0).
The members of BlockExportOptionsNbdBase
Since
5.0
nbd-server-add (Command)
Export a block node to QEMU's embedded NBD server.
The export name will be used as the id for the resulting block export.
Arguments
The members of NbdServerAddOptions
Features
deprecated
This command is deprecated. Use block-export-add instead.
Returns
error if the server is not running, or export with the same name al-
ready exists.
Since
1.3
BlockExportRemoveMode (Enum)
Mode for removing a block export.
Values
safe Remove export if there are no existing connections, fail other-
wise.
hard Drop all connections immediately and remove export.
TODO
Potential additional modes to be added in the future:
hide: Just hide export from new clients, leave existing connections as
is. Remove export after all clients are disconnected.
soft: Hide export from new clients, answer with ESHUTDOWN for all fur-
ther requests from existing clients.
Since
2.12
nbd-server-remove (Command)
Remove NBD export by name.
Arguments
name: string
Block export id.
mode: BlockExportRemoveMode (optional)
Mode of command operation. See BlockExportRemoveMode descrip-
tion. Default is 'safe'.
Features
deprecated
This command is deprecated. Use block-export-del instead.
Returns
error if
• the server is not running
• export is not found
• mode is 'safe' and there are existing connections
Since
2.12
nbd-server-stop (Command)
Stop QEMU's embedded NBD server, and unregister all devices previously
added via nbd-server-add.
Since
1.3
BlockExportType (Enum)
An enumeration of block export types
Values
nbd NBD export
vhost-user-blk (If: CONFIG_VHOST_USER_BLK_SERVER)
vhost-user-blk export (since 5.2)
fuse (If: CONFIG_FUSE)
FUSE export (since: 6.0)
vduse-blk (If: CONFIG_VDUSE_BLK_EXPORT)
vduse-blk export (since 7.1)
Since
4.2
BlockExportOptions (Object)
Describes a block export, i.e. how single node should be exported on an
external interface.
Members
id: string
A unique identifier for the block export (across all export
types)
node-name: string
The node name of the block node to be exported (since: 5.2)
writable: boolean (optional)
True if clients should be able to write to the export (default
false)
writethrough: boolean (optional)
If true, caches are flushed after every write request to the ex-
port before completion is signalled. (since: 5.2; default:
false)
iothread: string (optional)
The name of the iothread object where the export will run. The
default is to use the thread currently associated with the block
node. (since: 5.2)
fixed-iothread: boolean (optional)
True prevents the block node from being moved to another thread
while the export is active. If true and iothread is given, ex-
port creation fails if the block node cannot be moved to the io-
thread. The default is false. (since: 5.2)
type: BlockExportType
Not documented
The members of BlockExportOptionsNbd when type is "nbd"
The members of BlockExportOptionsVhostUserBlk when type is
"vhost-user-blk" (If: CONFIG_VHOST_USER_BLK_SERVER)
The members of BlockExportOptionsFuse when type is "fuse" (If: CON-
FIG_FUSE)
The members of BlockExportOptionsVduseBlk when type is "vduse-blk" (If:
CONFIG_VDUSE_BLK_EXPORT)
Since
4.2
block-export-add (Command)
Creates a new block export.
Arguments
The members of BlockExportOptions
Since
5.2
block-export-del (Command)
Request to remove a block export. This drops the user's reference to
the export, but the export may still stay around after this command re-
turns until the shutdown of the export has completed.
Arguments
id: string
Block export id.
mode: BlockExportRemoveMode (optional)
Mode of command operation. See BlockExportRemoveMode descrip-
tion. Default is 'safe'.
Returns
Error if the export is not found or mode is 'safe' and the export is
still in use (e.g. by existing client connections)
Since
5.2
BLOCK_EXPORT_DELETED (Event)
Emitted when a block export is removed and its id can be reused.
Arguments
id: string
Block export id.
Since
5.2
BlockExportInfo (Object)
Information about a single block export.
Members
id: string
The unique identifier for the block export
type: BlockExportType
The block export type
node-name: string
The node name of the block node that is exported
shutting-down: boolean
True if the export is shutting down (e.g. after a block-ex-
port-del command, but before the shutdown has completed)
Since
5.2
query-block-exports (Command)
Returns
A list of BlockExportInfo describing all block exports
Since
5.2
CHARACTER DEVICES
ChardevInfo (Object)
Information about a character device.
Members
label: string
the label of the character device
filename: string
the filename of the character device
frontend-open: boolean
shows whether the frontend device attached to this backend (eg.
with the chardev=... option) is in open or closed state (since
2.1)
Notes
filename is encoded using the QEMU command line character device encod-
ing. See the QEMU man page for details.
Since
0.14
query-chardev (Command)
Returns information about current character devices.
Returns
a list of ChardevInfo
Since
0.14
Example
-> { "execute": "query-chardev" }
<- {
"return": [
{
"label": "charchannel0",
"filename": "unix:/var/lib/libvirt/qemu/seabios.rhel6.agent,server=on",
"frontend-open": false
},
{
"label": "charmonitor",
"filename": "unix:/var/lib/libvirt/qemu/seabios.rhel6.monitor,server=on",
"frontend-open": true
},
{
"label": "charserial0",
"filename": "pty:/dev/pts/2",
"frontend-open": true
}
]
}
ChardevBackendInfo (Object)
Information about a character device backend
Members
name: string
The backend name
Since
2.0
query-chardev-backends (Command)
Returns information about character device backends.
Returns
a list of ChardevBackendInfo
Since
2.0
Example
-> { "execute": "query-chardev-backends" }
<- {
"return":[
{
"name":"udp"
},
{
"name":"tcp"
},
{
"name":"unix"
},
{
"name":"spiceport"
}
]
}
DataFormat (Enum)
An enumeration of data format.
Values
utf8 Data is a UTF-8 string (RFC 3629)
base64 Data is Base64 encoded binary (RFC 3548)
Since
1.4
ringbuf-write (Command)
Write to a ring buffer character device.
Arguments
device: string
the ring buffer character device name
data: string
data to write
format: DataFormat (optional)
data encoding (default 'utf8').
• base64: data must be base64 encoded text. Its binary decoding
gets written.
• utf8: data's UTF-8 encoding is written
• data itself is always Unicode regardless of format, like any
other string.
Returns
Nothing on success
Since
1.4
Example
-> { "execute": "ringbuf-write",
"arguments": { "device": "foo",
"data": "abcdefgh",
"format": "utf8" } }
<- { "return": {} }
ringbuf-read (Command)
Read from a ring buffer character device.
Arguments
device: string
the ring buffer character device name
size: int
how many bytes to read at most
format: DataFormat (optional)
data encoding (default 'utf8').
• base64: the data read is returned in base64 encoding.
• utf8: the data read is interpreted as UTF-8. Bug: can screw
up when the buffer contains invalid UTF-8 sequences, NUL char-
acters, after the ring buffer lost data, and when reading
stops because the size limit is reached.
• The return value is always Unicode regardless of format, like
any other string.
Returns
data read from the device
Since
1.4
Example
-> { "execute": "ringbuf-read",
"arguments": { "device": "foo",
"size": 1000,
"format": "utf8" } }
<- { "return": "abcdefgh" }
ChardevCommon (Object)
Configuration shared across all chardev backends
Members
logfile: string (optional)
The name of a logfile to save output
logappend: boolean (optional)
true to append instead of truncate (default to false to trun-
cate)
Since
2.6
ChardevFile (Object)
Configuration info for file chardevs.
Members
in: string (optional)
The name of the input file
out: string
The name of the output file
append: boolean (optional)
Open the file in append mode (default false to truncate) (Since
2.6)
The members of ChardevCommon
Since
1.4
ChardevHostdev (Object)
Configuration info for device and pipe chardevs.
Members
device: string
The name of the special file for the device, i.e. /dev/ttyS0 on
Unix or COM1: on Windows
The members of ChardevCommon
Since
1.4
ChardevSocket (Object)
Configuration info for (stream) socket chardevs.
Members
addr: SocketAddressLegacy
socket address to listen on (server=true) or connect to
(server=false)
tls-creds: string (optional)
the ID of the TLS credentials object (since 2.6)
tls-authz: string (optional)
the ID of the QAuthZ authorization object against which the
client's x509 distinguished name will be validated. This object
is only resolved at time of use, so can be deleted and recreated
on the fly while the chardev server is active. If missing, it
will default to denying access (since 4.0)
server: boolean (optional)
create server socket (default: true)
wait: boolean (optional)
wait for incoming connection on server sockets (default: false).
Silently ignored with server: false. This use is deprecated.
nodelay: boolean (optional)
set TCP_NODELAY socket option (default: false)
telnet: boolean (optional)
enable telnet protocol on server sockets (default: false)
tn3270: boolean (optional)
enable tn3270 protocol on server sockets (default: false)
(Since: 2.10)
websocket: boolean (optional)
enable websocket protocol on server sockets (default: false)
(Since: 3.1)
reconnect: int (optional)
For a client socket, if a socket is disconnected, then attempt a
reconnect after the given number of seconds. Setting this to
zero disables this function. (default: 0) (Since: 2.2)
The members of ChardevCommon
Since
1.4
ChardevUdp (Object)
Configuration info for datagram socket chardevs.
Members
remote: SocketAddressLegacy
remote address
local: SocketAddressLegacy (optional)
local address
The members of ChardevCommon
Since
1.5
ChardevMux (Object)
Configuration info for mux chardevs.
Members
chardev: string
name of the base chardev.
The members of ChardevCommon
Since
1.5
ChardevStdio (Object)
Configuration info for stdio chardevs.
Members
signal: boolean (optional)
Allow signals (such as SIGINT triggered by ^C) be delivered to
qemu. Default: true.
The members of ChardevCommon
Since
1.5
ChardevSpiceChannel (Object)
Configuration info for spice vm channel chardevs.
Members
type: string
kind of channel (for example vdagent).
The members of ChardevCommon
Since
1.5
If
CONFIG_SPICE
ChardevSpicePort (Object)
Configuration info for spice port chardevs.
Members
fqdn: string
name of the channel (see docs/spice-port-fqdn.txt)
The members of ChardevCommon
Since
1.5
If
CONFIG_SPICE
ChardevDBus (Object)
Configuration info for DBus chardevs.
Members
name: string
name of the channel (following docs/spice-port-fqdn.txt)
The members of ChardevCommon
Since
7.0
If
CONFIG_DBUS_DISPLAY
ChardevVC (Object)
Configuration info for virtual console chardevs.
Members
width: int (optional)
console width, in pixels
height: int (optional)
console height, in pixels
cols: int (optional)
console width, in chars
rows: int (optional)
console height, in chars
The members of ChardevCommon
Since
1.5
ChardevRingbuf (Object)
Configuration info for ring buffer chardevs.
Members
size: int (optional)
ring buffer size, must be power of two, default is 65536
The members of ChardevCommon
Since
1.5
ChardevQemuVDAgent (Object)
Configuration info for qemu vdagent implementation.
Members
mouse: boolean (optional)
enable/disable mouse, default is enabled.
clipboard: boolean (optional)
enable/disable clipboard, default is disabled.
The members of ChardevCommon
Since
6.1
If
CONFIG_SPICE_PROTOCOL
ChardevBackendKind (Enum)
Values
pipe Since 1.5
udp Since 1.5
mux Since 1.5
msmouse
Since 1.5
wctablet
Since 2.9
braille
Since 1.5
testdev
Since 2.2
stdio Since 1.5
console
Since 1.5
spicevmc (If: CONFIG_SPICE)
Since 1.5
spiceport (If: CONFIG_SPICE)
Since 1.5
qemu-vdagent (If: CONFIG_SPICE_PROTOCOL)
Since 6.1
dbus (If: CONFIG_DBUS_DISPLAY)
Since 7.0
vc v1.5
ringbuf
Since 1.6
memory Since 1.5
file Not documented
serial Not documented
parallel
Not documented
socket Not documented
pty Not documented
null Not documented
Since
1.4
ChardevFileWrapper (Object)
Members
data: ChardevFile
Not documented
Since
1.4
ChardevHostdevWrapper (Object)
Members
data: ChardevHostdev
Not documented
Since
1.4
ChardevSocketWrapper (Object)
Members
data: ChardevSocket
Not documented
Since
1.4
ChardevUdpWrapper (Object)
Members
data: ChardevUdp
Not documented
Since
1.5
ChardevCommonWrapper (Object)
Members
data: ChardevCommon
Not documented
Since
2.6
ChardevMuxWrapper (Object)
Members
data: ChardevMux
Not documented
Since
1.5
ChardevStdioWrapper (Object)
Members
data: ChardevStdio
Not documented
Since
1.5
ChardevSpiceChannelWrapper (Object)
Members
data: ChardevSpiceChannel
Not documented
Since
1.5
If
CONFIG_SPICE
ChardevSpicePortWrapper (Object)
Members
data: ChardevSpicePort
Not documented
Since
1.5
If
CONFIG_SPICE
ChardevQemuVDAgentWrapper (Object)
Members
data: ChardevQemuVDAgent
Not documented
Since
6.1
If
CONFIG_SPICE_PROTOCOL
ChardevDBusWrapper (Object)
Members
data: ChardevDBus
Not documented
Since
7.0
If
CONFIG_DBUS_DISPLAY
ChardevVCWrapper (Object)
Members
data: ChardevVC
Not documented
Since
1.5
ChardevRingbufWrapper (Object)
Members
data: ChardevRingbuf
Not documented
Since
1.5
ChardevBackend (Object)
Configuration info for the new chardev backend.
Members
type: ChardevBackendKind
Not documented
The members of ChardevFileWrapper when type is "file"
The members of ChardevHostdevWrapper when type is "serial"
The members of ChardevHostdevWrapper when type is "parallel"
The members of ChardevHostdevWrapper when type is "pipe"
The members of ChardevSocketWrapper when type is "socket"
The members of ChardevUdpWrapper when type is "udp"
The members of ChardevCommonWrapper when type is "pty"
The members of ChardevCommonWrapper when type is "null"
The members of ChardevMuxWrapper when type is "mux"
The members of ChardevCommonWrapper when type is "msmouse"
The members of ChardevCommonWrapper when type is "wctablet"
The members of ChardevCommonWrapper when type is "braille"
The members of ChardevCommonWrapper when type is "testdev"
The members of ChardevStdioWrapper when type is "stdio"
The members of ChardevCommonWrapper when type is "console"
The members of ChardevSpiceChannelWrapper when type is "spicevmc" (If:
CONFIG_SPICE)
The members of ChardevSpicePortWrapper when type is "spiceport" (If:
CONFIG_SPICE)
The members of ChardevQemuVDAgentWrapper when type is "qemu-vdagent"
(If: CONFIG_SPICE_PROTOCOL)
The members of ChardevDBusWrapper when type is "dbus" (If: CON-
FIG_DBUS_DISPLAY)
The members of ChardevVCWrapper when type is "vc"
The members of ChardevRingbufWrapper when type is "ringbuf"
The members of ChardevRingbufWrapper when type is "memory"
Since
1.4
ChardevReturn (Object)
Return info about the chardev backend just created.
Members
pty: string (optional)
name of the slave pseudoterminal device, present if and only if
a chardev of type 'pty' was created
Since
1.4
chardev-add (Command)
Add a character device backend
Arguments
id: string
the chardev's ID, must be unique
backend: ChardevBackend
backend type and parameters
Returns
ChardevReturn.
Since
1.4
Example
-> { "execute" : "chardev-add",
"arguments" : { "id" : "foo",
"backend" : { "type" : "null", "data" : {} } } }
<- { "return": {} }
-> { "execute" : "chardev-add",
"arguments" : { "id" : "bar",
"backend" : { "type" : "file",
"data" : { "out" : "/tmp/bar.log" } } } }
<- { "return": {} }
-> { "execute" : "chardev-add",
"arguments" : { "id" : "baz",
"backend" : { "type" : "pty", "data" : {} } } }
<- { "return": { "pty" : "/dev/pty/42" } }
chardev-change (Command)
Change a character device backend
Arguments
id: string
the chardev's ID, must exist
backend: ChardevBackend
new backend type and parameters
Returns
ChardevReturn.
Since
2.10
Example
-> { "execute" : "chardev-change",
"arguments" : { "id" : "baz",
"backend" : { "type" : "pty", "data" : {} } } }
<- { "return": { "pty" : "/dev/pty/42" } }
-> {"execute" : "chardev-change",
"arguments" : {
"id" : "charchannel2",
"backend" : {
"type" : "socket",
"data" : {
"addr" : {
"type" : "unix" ,
"data" : {
"path" : "/tmp/charchannel2.socket"
}
},
"server" : true,
"wait" : false }}}}
<- {"return": {}}
chardev-remove (Command)
Remove a character device backend
Arguments
id: string
the chardev's ID, must exist and not be in use
Returns
Nothing on success
Since
1.4
Example
-> { "execute": "chardev-remove", "arguments": { "id" : "foo" } }
<- { "return": {} }
chardev-send-break (Command)
Send a break to a character device
Arguments
id: string
the chardev's ID, must exist
Returns
Nothing on success
Since
2.10
Example
-> { "execute": "chardev-send-break", "arguments": { "id" : "foo" } }
<- { "return": {} }
VSERPORT_CHANGE (Event)
Emitted when the guest opens or closes a virtio-serial port.
Arguments
id: string
device identifier of the virtio-serial port
open: boolean
true if the guest has opened the virtio-serial port
Note
This event is rate-limited.
Since
2.1
Example
<- { "event": "VSERPORT_CHANGE",
"data": { "id": "channel0", "open": true },
"timestamp": { "seconds": 1401385907, "microseconds": 422329 } }
DUMP GUEST MEMORY
DumpGuestMemoryFormat (Enum)
An enumeration of guest-memory-dump's format.
Values
elf elf format
kdump-zlib
kdump-compressed format with zlib-compressed
kdump-lzo
kdump-compressed format with lzo-compressed
kdump-snappy
kdump-compressed format with snappy-compressed
win-dmp
Windows full crashdump format, can be used instead of ELF con-
verting (since 2.13)
Since
2.0
dump-guest-memory (Command)
Dump guest's memory to vmcore. It is a synchronous operation that can
take very long depending on the amount of guest memory.
Arguments
paging: boolean
if true, do paging to get guest's memory mapping. This allows
using gdb to process the core file.
IMPORTANT: this option can make QEMU allocate several gigabytes
of RAM. This can happen for a large guest, or a malicious guest
pretending to be large.
Also, paging=true has the following limitations:
1. The guest may be in a catastrophic state or can have cor-
rupted memory, which cannot be trusted
2. The guest can be in real-mode even if paging is enabled.
For example, the guest uses ACPI to sleep, and ACPI sleep
state goes in real-mode
3. Currently only supported on i386 and x86_64.
protocol: string
the filename or file descriptor of the vmcore. The supported
protocols are:
1. file: the protocol starts with "file:", and the following
string is the file's path.
2. fd: the protocol starts with "fd:", and the following string
is the fd's name.
detach: boolean (optional)
if true, QMP will return immediately rather than waiting for the
dump to finish. The user can track progress using "query-dump".
(since 2.6).
begin: int (optional)
if specified, the starting physical address.
length: int (optional)
if specified, the memory size, in bytes. If you don't want to
dump all guest's memory, please specify the start begin and
length
format: DumpGuestMemoryFormat (optional)
if specified, the format of guest memory dump. But non-elf for-
mat is conflict with paging and filter, ie. paging, begin and
length is not allowed to be specified with non-elf format at the
same time (since 2.0)
Note
All boolean arguments default to false
Returns
nothing on success
Since
1.2
Example
-> { "execute": "dump-guest-memory",
"arguments": { "paging": false, "protocol": "fd:dump" } }
<- { "return": {} }
DumpStatus (Enum)
Describe the status of a long-running background guest memory dump.
Values
none no dump-guest-memory has started yet.
active there is one dump running in background.
completed
the last dump has finished successfully.
failed the last dump has failed.
Since
2.6
DumpQueryResult (Object)
The result format for 'query-dump'.
Members
status: DumpStatus
enum of DumpStatus, which shows current dump status
completed: int
bytes written in latest dump (uncompressed)
total: int
total bytes to be written in latest dump (uncompressed)
Since
2.6
query-dump (Command)
Query latest dump status.
Returns
A DumpStatus object showing the dump status.
Since
2.6
Example
-> { "execute": "query-dump" }
<- { "return": { "status": "active", "completed": 1024000,
"total": 2048000 } }
DUMP_COMPLETED (Event)
Emitted when background dump has completed
Arguments
result: DumpQueryResult
final dump status
error: string (optional)
human-readable error string that provides hint on why dump
failed. Only presents on failure. The user should not try to in-
terpret the error string.
Since
2.6
Example
<- { "event": "DUMP_COMPLETED",
"data": { "result": { "total": 1090650112, "status": "completed",
"completed": 1090650112 } },
"timestamp": { "seconds": 1648244171, "microseconds": 950316 } }
DumpGuestMemoryCapability (Object)
A list of the available formats for dump-guest-memory
Members
formats: array of DumpGuestMemoryFormat
Not documented
Since
2.0
query-dump-guest-memory-capability (Command)
Returns the available formats for dump-guest-memory
Returns
A DumpGuestMemoryCapability object listing available formats for
dump-guest-memory
Since
2.0
Example
-> { "execute": "query-dump-guest-memory-capability" }
<- { "return": { "formats":
["elf", "kdump-zlib", "kdump-lzo", "kdump-snappy"] } }
NET DEVICES
set_link (Command)
Sets the link status of a virtual network adapter.
Arguments
name: string
the device name of the virtual network adapter
up: boolean
true to set the link status to be up
Returns
Nothing on success If name is not a valid network device, DeviceNot-
Found
Since
0.14
Notes
Not all network adapters support setting link status. This command
will succeed even if the network adapter does not support link status
notification.
Example
-> { "execute": "set_link",
"arguments": { "name": "e1000.0", "up": false } }
<- { "return": {} }
netdev_add (Command)
Add a network backend.
Additional arguments depend on the type.
Arguments
The members of Netdev
Since
0.14
Returns
Nothing on success If type is not a valid network backend, DeviceNot-
Found
Example
-> { "execute": "netdev_add",
"arguments": { "type": "user", "id": "netdev1",
"dnssearch": [ { "str": "example.org" } ] } }
<- { "return": {} }
netdev_del (Command)
Remove a network backend.
Arguments
id: string
the name of the network backend to remove
Returns
Nothing on success If id is not a valid network backend, DeviceNotFound
Since
0.14
Example
-> { "execute": "netdev_del", "arguments": { "id": "netdev1" } }
<- { "return": {} }
NetLegacyNicOptions (Object)
Create a new Network Interface Card.
Members
netdev: string (optional)
id of -netdev to connect to
macaddr: string (optional)
MAC address
model: string (optional)
device model (e1000, rtl8139, virtio etc.)
addr: string (optional)
PCI device address
vectors: int (optional)
number of MSI-x vectors, 0 to disable MSI-X
Since
1.2
NetdevUserOptions (Object)
Use the user mode network stack which requires no administrator privi-
lege to run.
Members
hostname: string (optional)
client hostname reported by the builtin DHCP server
restrict: boolean (optional)
isolate the guest from the host
ipv4: boolean (optional)
whether to support IPv4, default true for enabled (since 2.6)
ipv6: boolean (optional)
whether to support IPv6, default true for enabled (since 2.6)
ip: string (optional)
legacy parameter, use net= instead
net: string (optional)
IP network address that the guest will see, in the form
addr[/netmask] The netmask is optional, and can be either in the
form a.b.c.d or as a number of valid top-most bits. Default is
10.0.2.0/24.
host: string (optional)
guest-visible address of the host
tftp: string (optional)
root directory of the built-in TFTP server
bootfile: string (optional)
BOOTP filename, for use with tftp=
dhcpstart: string (optional)
the first of the 16 IPs the built-in DHCP server can assign
dns: string (optional)
guest-visible address of the virtual nameserver
dnssearch: array of String (optional)
list of DNS suffixes to search, passed as DHCP option to the
guest
domainname: string (optional)
guest-visible domain name of the virtual nameserver (since 3.0)
ipv6-prefix: string (optional)
IPv6 network prefix (default is fec0::) (since 2.6). The network
prefix is given in the usual hexadecimal IPv6 address notation.
ipv6-prefixlen: int (optional)
IPv6 network prefix length (default is 64) (since 2.6)
ipv6-host: string (optional)
guest-visible IPv6 address of the host (since 2.6)
ipv6-dns: string (optional)
guest-visible IPv6 address of the virtual nameserver (since 2.6)
smb: string (optional)
root directory of the built-in SMB server
smbserver: string (optional)
IP address of the built-in SMB server
hostfwd: array of String (optional)
redirect incoming TCP or UDP host connections to guest endpoints
guestfwd: array of String (optional)
forward guest TCP connections
tftp-server-name: string (optional)
RFC2132 "TFTP server name" string (Since 3.1)
Since
1.2
NetdevTapOptions (Object)
Used to configure a host TAP network interface backend.
Members
ifname: string (optional)
interface name
fd: string (optional)
file descriptor of an already opened tap
fds: string (optional)
multiple file descriptors of already opened multiqueue capable
tap
script: string (optional)
script to initialize the interface
downscript: string (optional)
script to shut down the interface
br: string (optional)
bridge name (since 2.8)
helper: string (optional)
command to execute to configure bridge
sndbuf: int (optional)
send buffer limit. Understands [TGMKkb] suffixes.
vnet_hdr: boolean (optional)
enable the IFF_VNET_HDR flag on the tap interface
vhost: boolean (optional)
enable vhost-net network accelerator
vhostfd: string (optional)
file descriptor of an already opened vhost net device
vhostfds: string (optional)
file descriptors of multiple already opened vhost net devices
vhostforce: boolean (optional)
vhost on for non-MSIX virtio guests
queues: int (optional)
number of queues to be created for multiqueue capable tap
poll-us: int (optional)
maximum number of microseconds that could be spent on busy
polling for tap (since 2.7)
Since
1.2
NetdevSocketOptions (Object)
Socket netdevs are used to establish a network connection to another
QEMU virtual machine via a TCP socket.
Members
fd: string (optional)
file descriptor of an already opened socket
listen: string (optional)
port number, and optional hostname, to listen on
connect: string (optional)
port number, and optional hostname, to connect to
mcast: string (optional)
UDP multicast address and port number
localaddr: string (optional)
source address and port for multicast and udp packets
udp: string (optional)
UDP unicast address and port number
Since
1.2
NetdevL2TPv3Options (Object)
Configure an Ethernet over L2TPv3 tunnel.
Members
src: string
source address
dst: string
destination address
srcport: string (optional)
source port - mandatory for udp, optional for ip
dstport: string (optional)
destination port - mandatory for udp, optional for ip
ipv6: boolean (optional)
force the use of ipv6
udp: boolean (optional)
use the udp version of l2tpv3 encapsulation
cookie64: boolean (optional)
use 64 bit cookies
counter: boolean (optional)
have sequence counter
pincounter: boolean (optional)
pin sequence counter to zero - workaround for buggy implementa-
tions or networks with packet reorder
txcookie: int (optional)
32 or 64 bit transmit cookie
rxcookie: int (optional)
32 or 64 bit receive cookie
txsession: int
32 bit transmit session
rxsession: int (optional)
32 bit receive session - if not specified set to the same value
as transmit
offset: int (optional)
additional offset - allows the insertion of additional applica-
tion-specific data before the packet payload
Since
2.1
NetdevVdeOptions (Object)
Connect to a vde switch running on the host.
Members
sock: string (optional)
socket path
port: int (optional)
port number
group: string (optional)
group owner of socket
mode: int (optional)
permissions for socket
Since
1.2
NetdevBridgeOptions (Object)
Connect a host TAP network interface to a host bridge device.
Members
br: string (optional)
bridge name
helper: string (optional)
command to execute to configure bridge
Since
1.2
NetdevHubPortOptions (Object)
Connect two or more net clients through a software hub.
Members
hubid: int
hub identifier number
netdev: string (optional)
used to connect hub to a netdev instead of a device (since 2.12)
Since
1.2
NetdevNetmapOptions (Object)
Connect a client to a netmap-enabled NIC or to a VALE switch port
Members
ifname: string
Either the name of an existing network interface supported by
netmap, or the name of a VALE port (created on the fly). A VALE
port name is in the form 'valeXXX:YYY', where XXX and YYY are
non-negative integers. XXX identifies a switch and YYY identi-
fies a port of the switch. VALE ports having the same XXX are
therefore connected to the same switch.
devname: string (optional)
path of the netmap device (default: '/dev/netmap').
Since
2.0
NetdevVhostUserOptions (Object)
Vhost-user network backend
Members
chardev: string
name of a unix socket chardev
vhostforce: boolean (optional)
vhost on for non-MSIX virtio guests (default: false).
queues: int (optional)
number of queues to be created for multiqueue vhost-user (de-
fault: 1) (Since 2.5)
Since
2.1
NetdevVhostVDPAOptions (Object)
Vhost-vdpa network backend
vDPA device is a device that uses a datapath which complies with the
virtio specifications with a vendor specific control path.
Members
vhostdev: string (optional)
path of vhost-vdpa device (default:'/dev/vhost-vdpa-0')
vhostfd: string (optional)
file descriptor of an already opened vhost vdpa device
queues: int (optional)
number of queues to be created for multiqueue vhost-vdpa (de-
fault: 1)
x-svq: boolean (optional)
Start device with (experimental) shadow virtqueue. (Since 7.1)
(default: false)
Features
unstable
Member x-svq is experimental.
Since
5.1
NetdevVmnetHostOptions (Object)
vmnet (host mode) network backend.
Allows the vmnet interface to communicate with other vmnet interfaces
that are in host mode and also with the host.
Members
start-address: string (optional)
The starting IPv4 address to use for the interface. Must be in
the private IP range (RFC 1918). Must be specified along with
end-address and subnet-mask. This address is used as the gate-
way address. The subsequent address up to and including end-ad-
dress are placed in the DHCP pool.
end-address: string (optional)
The DHCP IPv4 range end address to use for the interface. Must
be in the private IP range (RFC 1918). Must be specified along
with start-address and subnet-mask.
subnet-mask: string (optional)
The IPv4 subnet mask to use on the interface. Must be specified
along with start-address and subnet-mask.
isolated: boolean (optional)
Enable isolation for this interface. Interface isolation ensures
that vmnet interface is not able to communicate with any other
vmnet interfaces. Only communication with host is allowed. Re-
quires at least macOS Big Sur 11.0.
net-uuid: string (optional)
The identifier (UUID) to uniquely identify the isolated network
vmnet interface should be added to. If set, no DHCP service is
provided for this interface and network communication is allowed
only with other interfaces added to this network identified by
the UUID. Requires at least macOS Big Sur 11.0.
Since
7.1
If
CONFIG_VMNET
NetdevVmnetSharedOptions (Object)
vmnet (shared mode) network backend.
Allows traffic originating from the vmnet interface to reach the Inter-
net through a network address translator (NAT). The vmnet interface
can communicate with the host and with other shared mode interfaces on
the same subnet. If no DHCP settings, subnet mask and IPv6 prefix spec-
ified, the interface can communicate with any of other interfaces in
shared mode.
Members
start-address: string (optional)
The starting IPv4 address to use for the interface. Must be in
the private IP range (RFC 1918). Must be specified along with
end-address and subnet-mask. This address is used as the gate-
way address. The subsequent address up to and including end-ad-
dress are placed in the DHCP pool.
end-address: string (optional)
The DHCP IPv4 range end address to use for the interface. Must
be in the private IP range (RFC 1918). Must be specified along
with start-address and subnet-mask.
subnet-mask: string (optional)
The IPv4 subnet mask to use on the interface. Must
be specified along with start-address and subnet-mask.
isolated: boolean (optional)
Enable isolation for this interface. Interface isolation ensures
that vmnet interface is not able to communicate with any other
vmnet interfaces. Only communication with host is allowed. Re-
quires at least macOS Big Sur 11.0.
nat66-prefix: string (optional)
The IPv6 prefix to use into guest network. Must be a unique lo-
cal address i.e. start with fd00::/8 and have length of 64.
Since
7.1
If
CONFIG_VMNET
NetdevVmnetBridgedOptions (Object)
vmnet (bridged mode) network backend.
Bridges the vmnet interface with a physical network interface.
Members
ifname: string
The name of the physical interface to be bridged.
isolated: boolean (optional)
Enable isolation for this interface. Interface isolation ensures
that vmnet interface is not able to communicate with any other
vmnet interfaces. Only communication with host is allowed. Re-
quires at least macOS Big Sur 11.0.
Since
7.1
If
CONFIG_VMNET
NetdevStreamOptions (Object)
Configuration info for stream socket netdev
Members
addr: SocketAddress
socket address to listen on (server=true) or connect to
(server=false)
server: boolean (optional)
create server socket (default: false)
Only SocketAddress types 'unix', 'inet' and 'fd' are supported.
Since
7.2
NetdevDgramOptions (Object)
Configuration info for datagram socket netdev.
Members
remote: SocketAddress (optional)
remote address
local: SocketAddress (optional)
local address
Only SocketAddress types 'unix', 'inet' and 'fd' are supported.
If remote address is present and it's a multicast address, local ad-
dress is optional. Otherwise local address is required and remote ad-
dress is optional.
Valid parameters combination table
┌──────────────┬─────────┬───────┐
│remote │ local │ okay? │
├──────────────┼─────────┼───────┤
│absent │ absent │ no │
├──────────────┼─────────┼───────┤
│absent │ not fd │ no │
├──────────────┼─────────┼───────┤
│absent │ fd │ yes │
├──────────────┼─────────┼───────┤
│multicast │ absent │ yes │
├──────────────┼─────────┼───────┤
│multicast │ present │ yes │
├──────────────┼─────────┼───────┤
│not multicast │ absent │ no │
├──────────────┼─────────┼───────┤
│not multicast │ present │ yes │
└──────────────┴─────────┴───────┘
Since
7.2
NetClientDriver (Enum)
Available netdev drivers.
Values
none Not documented
nic Not documented
user Not documented
tap Not documented
l2tpv3 Not documented
socket Not documented
stream Not documented
dgram Not documented
vde Not documented
bridge Not documented
hubport
Not documented
netmap Not documented
vhost-user
Not documented
vhost-vdpa
Not documented
vmnet-host (If: CONFIG_VMNET)
Not documented
vmnet-shared (If: CONFIG_VMNET)
Not documented
vmnet-bridged (If: CONFIG_VMNET)
Not documented
Since
2.7
vhost-vdpa since 5.1 vmnet-host since 7.1 vmnet-shared since 7.1 vm-
net-bridged since 7.1 stream since 7.2 dgram since 7.2
Netdev (Object)
Captures the configuration of a network device.
Members
id: string
identifier for monitor commands.
type: NetClientDriver
Specify the driver used for interpreting remaining arguments.
The members of NetLegacyNicOptions when type is "nic"
The members of NetdevUserOptions when type is "user"
The members of NetdevTapOptions when type is "tap"
The members of NetdevL2TPv3Options when type is "l2tpv3"
The members of NetdevSocketOptions when type is "socket"
The members of NetdevStreamOptions when type is "stream"
The members of NetdevDgramOptions when type is "dgram"
The members of NetdevVdeOptions when type is "vde"
The members of NetdevBridgeOptions when type is "bridge"
The members of NetdevHubPortOptions when type is "hubport"
The members of NetdevNetmapOptions when type is "netmap"
The members of NetdevVhostUserOptions when type is "vhost-user"
The members of NetdevVhostVDPAOptions when type is "vhost-vdpa"
The members of NetdevVmnetHostOptions when type is "vmnet-host" (If:
CONFIG_VMNET)
The members of NetdevVmnetSharedOptions when type is "vmnet-shared"
(If: CONFIG_VMNET)
The members of NetdevVmnetBridgedOptions when type is "vmnet-bridged"
(If: CONFIG_VMNET)
Since
1.2
'l2tpv3' - since 2.1 'vmnet-host' - since 7.1 'vmnet-shared' - since
7.1 'vmnet-bridged' - since 7.1 'stream' since 7.2 'dgram' since 7.2
RxState (Enum)
Packets receiving state
Values
normal filter assigned packets according to the mac-table
none don't receive any assigned packet
all receive all assigned packets
Since
1.6
RxFilterInfo (Object)
Rx-filter information for a NIC.
Members
name: string
net client name
promiscuous: boolean
whether promiscuous mode is enabled
multicast: RxState
multicast receive state
unicast: RxState
unicast receive state
vlan: RxState
vlan receive state (Since 2.0)
broadcast-allowed: boolean
whether to receive broadcast
multicast-overflow: boolean
multicast table is overflowed or not
unicast-overflow: boolean
unicast table is overflowed or not
main-mac: string
the main macaddr string
vlan-table: array of int
a list of active vlan id
unicast-table: array of string
a list of unicast macaddr string
multicast-table: array of string
a list of multicast macaddr string
Since
1.6
query-rx-filter (Command)
Return rx-filter information for all NICs (or for the given NIC).
Arguments
name: string (optional)
net client name
Returns
list of RxFilterInfo for all NICs (or for the given NIC). Returns an
error if the given name doesn't exist, or given NIC doesn't support
rx-filter querying, or given net client isn't a NIC.
Since
1.6
Example
-> { "execute": "query-rx-filter", "arguments": { "name": "vnet0" } }
<- { "return": [
{
"promiscuous": true,
"name": "vnet0",
"main-mac": "52:54:00:12:34:56",
"unicast": "normal",
"vlan": "normal",
"vlan-table": [
4,
0
],
"unicast-table": [
],
"multicast": "normal",
"multicast-overflow": false,
"unicast-overflow": false,
"multicast-table": [
"01:00:5e:00:00:01",
"33:33:00:00:00:01",
"33:33:ff:12:34:56"
],
"broadcast-allowed": false
}
]
}
NIC_RX_FILTER_CHANGED (Event)
Emitted once until the 'query-rx-filter' command is executed, the first
event will always be emitted
Arguments
name: string (optional)
net client name
path: string
device path
Since
1.6
Example
<- { "event": "NIC_RX_FILTER_CHANGED",
"data": { "name": "vnet0",
"path": "/machine/peripheral/vnet0/virtio-backend" },
"timestamp": { "seconds": 1368697518, "microseconds": 326866 } }
AnnounceParameters (Object)
Parameters for self-announce timers
Members
initial: int
Initial delay (in ms) before sending the first GARP/RARP an-
nouncement
max: int
Maximum delay (in ms) between GARP/RARP announcement packets
rounds: int
Number of self-announcement attempts
step: int
Delay increase (in ms) after each self-announcement attempt
interfaces: array of string (optional)
An optional list of interface names, which restricts the an-
nouncement to the listed interfaces. (Since 4.1)
id: string (optional)
A name to be used to identify an instance of announce-timers and
to allow it to modified later. Not for use as part of the mi-
gration parameters. (Since 4.1)
Since
4.0
announce-self (Command)
Trigger generation of broadcast RARP frames to update network switches.
This can be useful when network bonds fail-over the active slave.
Arguments
The members of AnnounceParameters
Example
-> { "execute": "announce-self",
"arguments": {
"initial": 50, "max": 550, "rounds": 10, "step": 50,
"interfaces": ["vn2", "vn3"], "id": "bob" } }
<- { "return": {} }
Since
4.0
FAILOVER_NEGOTIATED (Event)
Emitted when VIRTIO_NET_F_STANDBY was enabled during feature negotia-
tion. Failover primary devices which were hidden (not hotplugged when
requested) before will now be hotplugged by the virtio-net standby de-
vice.
Arguments
device-id: string
QEMU device id of the unplugged device
Since
4.2
Example
<- { "event": "FAILOVER_NEGOTIATED",
"data": { "device-id": "net1" },
"timestamp": { "seconds": 1368697518, "microseconds": 326866 } }
NETDEV_STREAM_CONNECTED (Event)
Emitted when the netdev stream backend is connected
Arguments
netdev-id: string
QEMU netdev id that is connected
addr: SocketAddress
The destination address
Since
7.2
Example
<- { "event": "NETDEV_STREAM_CONNECTED",
"data": { "netdev-id": "netdev0",
"addr": { "port": "47666", "ipv6": true,
"host": "::1", "type": "inet" } },
"timestamp": { "seconds": 1666269863, "microseconds": 311222 } }
or
<- { "event": "NETDEV_STREAM_CONNECTED",
"data": { "netdev-id": "netdev0",
"addr": { "path": "/tmp/qemu0", "type": "unix" } },
"timestamp": { "seconds": 1666269706, "microseconds": 413651 } }
NETDEV_STREAM_DISCONNECTED (Event)
Emitted when the netdev stream backend is disconnected
Arguments
netdev-id: string
QEMU netdev id that is disconnected
Since
7.2
Example
<- { 'event': 'NETDEV_STREAM_DISCONNECTED',
'data': {'netdev-id': 'netdev0'},
'timestamp': {'seconds': 1663330937, 'microseconds': 526695} }
RDMA DEVICE
RDMA_GID_STATUS_CHANGED (Event)
Emitted when guest driver adds/deletes GID to/from device
Arguments
netdev: string
RoCE Network Device name
gid-status: boolean
Add or delete indication
subnet-prefix: int
Subnet Prefix
interface-id: int
Not documented
interface-id : Interface ID
Since
4.0
Example
<- {"timestamp": {"seconds": 1541579657, "microseconds": 986760},
"event": "RDMA_GID_STATUS_CHANGED",
"data":
{"netdev": "bridge0",
"interface-id": 15880512517475447892,
"gid-status": true,
"subnet-prefix": 33022}}
ROCKER SWITCH DEVICE
RockerSwitch (Object)
Rocker switch information.
Members
name: string
switch name
id: int
switch ID
ports: int
number of front-panel ports
Since
2.4
query-rocker (Command)
Return rocker switch information.
Arguments
name: string
Not documented
Returns
Rocker information
Since
2.4
Example
-> { "execute": "query-rocker", "arguments": { "name": "sw1" } }
<- { "return": {"name": "sw1", "ports": 2, "id": 1327446905938}}
RockerPortDuplex (Enum)
An eumeration of port duplex states.
Values
half half duplex
full full duplex
Since
2.4
RockerPortAutoneg (Enum)
An eumeration of port autoneg states.
Values
off autoneg is off
on autoneg is on
Since
2.4
RockerPort (Object)
Rocker switch port information.
Members
name: string
port name
enabled: boolean
port is enabled for I/O
link-up: boolean
physical link is UP on port
speed: int
port link speed in Mbps
duplex: RockerPortDuplex
port link duplex
autoneg: RockerPortAutoneg
port link autoneg
Since
2.4
query-rocker-ports (Command)
Return rocker switch port information.
Arguments
name: string
Not documented
Returns
a list of RockerPort information
Since
2.4
Example
-> { "execute": "query-rocker-ports", "arguments": { "name": "sw1" } }
<- { "return": [ {"duplex": "full", "enabled": true, "name": "sw1.1",
"autoneg": "off", "link-up": true, "speed": 10000},
{"duplex": "full", "enabled": true, "name": "sw1.2",
"autoneg": "off", "link-up": true, "speed": 10000}
]}
RockerOfDpaFlowKey (Object)
Rocker switch OF-DPA flow key
Members
priority: int
key priority, 0 being lowest priority
tbl-id: int
flow table ID
in-pport: int (optional)
physical input port
tunnel-id: int (optional)
tunnel ID
vlan-id: int (optional)
VLAN ID
eth-type: int (optional)
Ethernet header type
eth-src: string (optional)
Ethernet header source MAC address
eth-dst: string (optional)
Ethernet header destination MAC address
ip-proto: int (optional)
IP Header protocol field
ip-tos: int (optional)
IP header TOS field
ip-dst: string (optional)
IP header destination address
Note
optional members may or may not appear in the flow key depending if
they're relevant to the flow key.
Since
2.4
RockerOfDpaFlowMask (Object)
Rocker switch OF-DPA flow mask
Members
in-pport: int (optional)
physical input port
tunnel-id: int (optional)
tunnel ID
vlan-id: int (optional)
VLAN ID
eth-src: string (optional)
Ethernet header source MAC address
eth-dst: string (optional)
Ethernet header destination MAC address
ip-proto: int (optional)
IP Header protocol field
ip-tos: int (optional)
IP header TOS field
Note
optional members may or may not appear in the flow mask depending if
they're relevant to the flow mask.
Since
2.4
RockerOfDpaFlowAction (Object)
Rocker switch OF-DPA flow action
Members
goto-tbl: int (optional)
next table ID
group-id: int (optional)
group ID
tunnel-lport: int (optional)
tunnel logical port ID
vlan-id: int (optional)
VLAN ID
new-vlan-id: int (optional)
new VLAN ID
out-pport: int (optional)
physical output port
Note
optional members may or may not appear in the flow action depending if
they're relevant to the flow action.
Since
2.4
RockerOfDpaFlow (Object)
Rocker switch OF-DPA flow
Members
cookie: int
flow unique cookie ID
hits: int
count of matches (hits) on flow
key: RockerOfDpaFlowKey
flow key
mask: RockerOfDpaFlowMask
flow mask
action: RockerOfDpaFlowAction
flow action
Since
2.4
query-rocker-of-dpa-flows (Command)
Return rocker OF-DPA flow information.
Arguments
name: string
switch name
tbl-id: int (optional)
flow table ID. If tbl-id is not specified, returns flow infor-
mation for all tables.
Returns
rocker OF-DPA flow information
Since
2.4
Example
-> { "execute": "query-rocker-of-dpa-flows",
"arguments": { "name": "sw1" } }
<- { "return": [ {"key": {"in-pport": 0, "priority": 1, "tbl-id": 0},
"hits": 138,
"cookie": 0,
"action": {"goto-tbl": 10},
"mask": {"in-pport": 4294901760}
},
{...more...},
]}
RockerOfDpaGroup (Object)
Rocker switch OF-DPA group
Members
id: int
group unique ID
type: int
group type
vlan-id: int (optional)
VLAN ID
pport: int (optional)
physical port number
index: int (optional)
group index, unique with group type
out-pport: int (optional)
output physical port number
group-id: int (optional)
next group ID
set-vlan-id: int (optional)
VLAN ID to set
pop-vlan: int (optional)
pop VLAN headr from packet
group-ids: array of int (optional)
list of next group IDs
set-eth-src: string (optional)
set source MAC address in Ethernet header
set-eth-dst: string (optional)
set destination MAC address in Ethernet header
ttl-check: int (optional)
perform TTL check
Note
optional members may or may not appear in the group depending if
they're relevant to the group type.
Since
2.4
query-rocker-of-dpa-groups (Command)
Return rocker OF-DPA group information.
Arguments
name: string
switch name
type: int (optional)
group type. If type is not specified, returns group information
for all group types.
Returns
rocker OF-DPA group information
Since
2.4
Example
-> { "execute": "query-rocker-of-dpa-groups",
"arguments": { "name": "sw1" } }
<- { "return": [ {"type": 0, "out-pport": 2,
"pport": 2, "vlan-id": 3841,
"pop-vlan": 1, "id": 251723778},
{"type": 0, "out-pport": 0,
"pport": 0, "vlan-id": 3841,
"pop-vlan": 1, "id": 251723776},
{"type": 0, "out-pport": 1,
"pport": 1, "vlan-id": 3840,
"pop-vlan": 1, "id": 251658241},
{"type": 0, "out-pport": 0,
"pport": 0, "vlan-id": 3840,
"pop-vlan": 1, "id": 251658240}
]}
TPM (TRUSTED PLATFORM MODULE) DEVICES
TpmModel (Enum)
An enumeration of TPM models
Values
tpm-tis
TPM TIS model
tpm-crb
TPM CRB model (since 2.12)
tpm-spapr
TPM SPAPR model (since 5.0)
Since
1.5
If
CONFIG_TPM
query-tpm-models (Command)
Return a list of supported TPM models
Returns
a list of TpmModel
Since
1.5
Example
-> { "execute": "query-tpm-models" }
<- { "return": [ "tpm-tis", "tpm-crb", "tpm-spapr" ] }
If
CONFIG_TPM
TpmType (Enum)
An enumeration of TPM types
Values
passthrough
TPM passthrough type
emulator
Software Emulator TPM type Since: 2.11
Since
1.5
If
CONFIG_TPM
query-tpm-types (Command)
Return a list of supported TPM types
Returns
a list of TpmType
Since
1.5
Example
-> { "execute": "query-tpm-types" }
<- { "return": [ "passthrough", "emulator" ] }
If
CONFIG_TPM
TPMPassthroughOptions (Object)
Information about the TPM passthrough type
Members
path: string (optional)
string describing the path used for accessing the TPM device
cancel-path: string (optional)
string showing the TPM's sysfs cancel file for cancellation of
TPM commands while they are executing
Since
1.5
If
CONFIG_TPM
TPMEmulatorOptions (Object)
Information about the TPM emulator type
Members
chardev: string
Name of a unix socket chardev
Since
2.11
If
CONFIG_TPM
TPMPassthroughOptionsWrapper (Object)
Members
data: TPMPassthroughOptions
Not documented
Since
1.5
If
CONFIG_TPM
TPMEmulatorOptionsWrapper (Object)
Members
data: TPMEmulatorOptions
Not documented
Since
2.11
If
CONFIG_TPM
TpmTypeOptions (Object)
A union referencing different TPM backend types' configuration options
Members
type: TpmType
• 'passthrough' The configuration options for the TPM
passthrough type
• 'emulator' The configuration options for TPM emulator backend
type
The members of TPMPassthroughOptionsWrapper when type is "passthrough"
The members of TPMEmulatorOptionsWrapper when type is "emulator"
Since
1.5
If
CONFIG_TPM
TPMInfo (Object)
Information about the TPM
Members
id: string
The Id of the TPM
model: TpmModel
The TPM frontend model
options: TpmTypeOptions
The TPM (backend) type configuration options
Since
1.5
If
CONFIG_TPM
query-tpm (Command)
Return information about the TPM device
Returns
TPMInfo on success
Since
1.5
Example
-> { "execute": "query-tpm" }
<- { "return":
[
{ "model": "tpm-tis",
"options":
{ "type": "passthrough",
"data":
{ "cancel-path": "/sys/class/misc/tpm0/device/cancel",
"path": "/dev/tpm0"
}
},
"id": "tpm0"
}
]
}
If
CONFIG_TPM
REMOTE DESKTOP
DisplayProtocol (Enum)
Display protocols which support changing password options.
Values
vnc Not documented
spice Not documented
Since
7.0
SetPasswordAction (Enum)
An action to take on changing a password on a connection with active
clients.
Values
keep maintain existing clients
fail fail the command if clients are connected
disconnect
disconnect existing clients
Since
7.0
SetPasswordOptions (Object)
Options for set_password.
Members
protocol: DisplayProtocol
• 'vnc' to modify the VNC server password
• 'spice' to modify the Spice server password
password: string
the new password
connected: SetPasswordAction (optional)
How to handle existing clients when changing the password. If
nothing is specified, defaults to 'keep'. For VNC, only 'keep'
is currently implemented.
The members of SetPasswordOptionsVnc when protocol is "vnc"
Since
7.0
SetPasswordOptionsVnc (Object)
Options for set_password specific to the VNC procotol.
Members
display: string (optional)
The id of the display where the password should be changed. De-
faults to the first.
Since
7.0
set_password (Command)
Set the password of a remote display server.
Arguments
The members of SetPasswordOptions
Returns
• Nothing on success
• If Spice is not enabled, DeviceNotFound
Since
0.14
Example
-> { "execute": "set_password", "arguments": { "protocol": "vnc",
"password": "secret" } }
<- { "return": {} }
ExpirePasswordOptions (Object)
General options for expire_password.
Members
protocol: DisplayProtocol
• 'vnc' to modify the VNC server expiration
• 'spice' to modify the Spice server expiration
time: string
when to expire the password.
• 'now' to expire the password immediately
• 'never' to cancel password expiration
• '+INT' where INT is the number of seconds from now (integer)
• 'INT' where INT is the absolute time in seconds
The members of ExpirePasswordOptionsVnc when protocol is "vnc"
Notes
Time is relative to the server and currently there is no way to coordi-
nate server time with client time. It is not recommended to use the
absolute time version of the time parameter unless you're sure you are
on the same machine as the QEMU instance.
Since
7.0
ExpirePasswordOptionsVnc (Object)
Options for expire_password specific to the VNC procotol.
Members
display: string (optional)
The id of the display where the expiration should be changed.
Defaults to the first.
Since
7.0
expire_password (Command)
Expire the password of a remote display server.
Arguments
The members of ExpirePasswordOptions
Returns
• Nothing on success
• If protocol is 'spice' and Spice is not active, DeviceNotFound
Since
0.14
Example
-> { "execute": "expire_password", "arguments": { "protocol": "vnc",
"time": "+60" } }
<- { "return": {} }
ImageFormat (Enum)
Supported image format types.
Values
png PNG format
ppm PPM format
Since
7.1
screendump (Command)
Capture the contents of a screen and write it to a file.
Arguments
filename: string
the path of a new file to store the image
device: string (optional)
ID of the display device that should be dumped. If this parame-
ter is missing, the primary display will be used. (Since 2.12)
head: int (optional)
head to use in case the device supports multiple heads. If this
parameter is missing, head #0 will be used. Also note that the
head can only be specified in conjunction with the device ID.
(Since 2.12)
format: ImageFormat (optional)
image format for screendump. (default: ppm) (Since 7.1)
Returns
Nothing on success
Since
0.14
Example
-> { "execute": "screendump",
"arguments": { "filename": "/tmp/image" } }
<- { "return": {} }
Spice
SpiceBasicInfo (Object)
The basic information for SPICE network connection
Members
host: string
IP address
port: string
port number
family: NetworkAddressFamily
address family
Since
2.1
If
CONFIG_SPICE
SpiceServerInfo (Object)
Information about a SPICE server
Members
auth: string (optional)
authentication method
The members of SpiceBasicInfo
Since
2.1
If
CONFIG_SPICE
SpiceChannel (Object)
Information about a SPICE client channel.
Members
connection-id: int
SPICE connection id number. All channels with the same id be-
long to the same SPICE session.
channel-type: int
SPICE channel type number. "1" is the main control channel,
filter for this one if you want to track spice sessions only
channel-id: int
SPICE channel ID number. Usually "0", might be different when
multiple channels of the same type exist, such as multiple dis-
play channels in a multihead setup
tls: boolean
true if the channel is encrypted, false otherwise.
The members of SpiceBasicInfo
Since
0.14
If
CONFIG_SPICE
SpiceQueryMouseMode (Enum)
An enumeration of Spice mouse states.
Values
client Mouse cursor position is determined by the client.
server Mouse cursor position is determined by the server.
unknown
No information is available about mouse mode used by the spice
server.
Note
spice/enums.h has a SpiceMouseMode already, hence the name.
Since
1.1
If
CONFIG_SPICE
SpiceInfo (Object)
Information about the SPICE session.
Members
enabled: boolean
true if the SPICE server is enabled, false otherwise
migrated: boolean
true if the last guest migration completed and spice migration
had completed as well. false otherwise. (since 1.4)
host: string (optional)
The hostname the SPICE server is bound to. This depends on the
name resolution on the host and may be an IP address.
port: int (optional)
The SPICE server's port number.
compiled-version: string (optional)
SPICE server version.
tls-port: int (optional)
The SPICE server's TLS port number.
auth: string (optional)
the current authentication type used by the server
• 'none' if no authentication is being used
• 'spice' uses SASL or direct TLS authentication, depending on
command line options
mouse-mode: SpiceQueryMouseMode
The mode in which the mouse cursor is displayed currently. Can
be determined by the client or the server, or unknown if spice
server doesn't provide this information. (since: 1.1)
channels: array of SpiceChannel (optional)
a list of SpiceChannel for each active spice channel
Since
0.14
If
CONFIG_SPICE
query-spice (Command)
Returns information about the current SPICE server
Returns
SpiceInfo
Since
0.14
Example
-> { "execute": "query-spice" }
<- { "return": {
"enabled": true,
"auth": "spice",
"port": 5920,
"migrated":false,
"tls-port": 5921,
"host": "0.0.0.0",
"mouse-mode":"client",
"channels": [
{
"port": "54924",
"family": "ipv4",
"channel-type": 1,
"connection-id": 1804289383,
"host": "127.0.0.1",
"channel-id": 0,
"tls": true
},
{
"port": "36710",
"family": "ipv4",
"channel-type": 4,
"connection-id": 1804289383,
"host": "127.0.0.1",
"channel-id": 0,
"tls": false
},
[ ... more channels follow ... ]
]
}
}
If
CONFIG_SPICE
SPICE_CONNECTED (Event)
Emitted when a SPICE client establishes a connection
Arguments
server: SpiceBasicInfo
server information
client: SpiceBasicInfo
client information
Since
0.14
Example
<- { "timestamp": {"seconds": 1290688046, "microseconds": 388707},
"event": "SPICE_CONNECTED",
"data": {
"server": { "port": "5920", "family": "ipv4", "host": "127.0.0.1"},
"client": {"port": "52873", "family": "ipv4", "host": "127.0.0.1"}
}}
If
CONFIG_SPICE
SPICE_INITIALIZED (Event)
Emitted after initial handshake and authentication takes place (if any)
and the SPICE channel is up and running
Arguments
server: SpiceServerInfo
server information
client: SpiceChannel
client information
Since
0.14
Example
<- { "timestamp": {"seconds": 1290688046, "microseconds": 417172},
"event": "SPICE_INITIALIZED",
"data": {"server": {"auth": "spice", "port": "5921",
"family": "ipv4", "host": "127.0.0.1"},
"client": {"port": "49004", "family": "ipv4", "channel-type": 3,
"connection-id": 1804289383, "host": "127.0.0.1",
"channel-id": 0, "tls": true}
}}
If
CONFIG_SPICE
SPICE_DISCONNECTED (Event)
Emitted when the SPICE connection is closed
Arguments
server: SpiceBasicInfo
server information
client: SpiceBasicInfo
client information
Since
0.14
Example
<- { "timestamp": {"seconds": 1290688046, "microseconds": 388707},
"event": "SPICE_DISCONNECTED",
"data": {
"server": { "port": "5920", "family": "ipv4", "host": "127.0.0.1"},
"client": {"port": "52873", "family": "ipv4", "host": "127.0.0.1"}
}}
If
CONFIG_SPICE
SPICE_MIGRATE_COMPLETED (Event)
Emitted when SPICE migration has completed
Since
1.3
Example
<- { "timestamp": {"seconds": 1290688046, "microseconds": 417172},
"event": "SPICE_MIGRATE_COMPLETED" }
If
CONFIG_SPICE
VNC
VncBasicInfo (Object)
The basic information for vnc network connection
Members
host: string
IP address
service: string
The service name of the vnc port. This may depend on the host
system's service database so symbolic names should not be relied
on.
family: NetworkAddressFamily
address family
websocket: boolean
true in case the socket is a websocket (since 2.3).
Since
2.1
If
CONFIG_VNC
VncServerInfo (Object)
The network connection information for server
Members
auth: string (optional)
authentication method used for the plain (non-websocket) VNC
server
The members of VncBasicInfo
Since
2.1
If
CONFIG_VNC
VncClientInfo (Object)
Information about a connected VNC client.
Members
x509_dname: string (optional)
If x509 authentication is in use, the Distinguished Name of the
client.
sasl_username: string (optional)
If SASL authentication is in use, the SASL username used for au-
thentication.
The members of VncBasicInfo
Since
0.14
If
CONFIG_VNC
VncInfo (Object)
Information about the VNC session.
Members
enabled: boolean
true if the VNC server is enabled, false otherwise
host: string (optional)
The hostname the VNC server is bound to. This depends on the
name resolution on the host and may be an IP address.
family: NetworkAddressFamily (optional)
• 'ipv6' if the host is listening for IPv6 connections
• 'ipv4' if the host is listening for IPv4 connections
• 'unix' if the host is listening on a unix domain socket
• 'unknown' otherwise
service: string (optional)
The service name of the server's port. This may depends on the
host system's service database so symbolic names should not be
relied on.
auth: string (optional)
the current authentication type used by the server
• 'none' if no authentication is being used
• 'vnc' if VNC authentication is being used
• 'vencrypt+plain' if VEncrypt is used with plain text authenti-
cation
• 'vencrypt+tls+none' if VEncrypt is used with TLS and no au-
thentication
• 'vencrypt+tls+vnc' if VEncrypt is used with TLS and VNC au-
thentication
• 'vencrypt+tls+plain' if VEncrypt is used with TLS and plain
text auth
• 'vencrypt+x509+none' if VEncrypt is used with x509 and no auth
• 'vencrypt+x509+vnc' if VEncrypt is used with x509 and VNC auth
• 'vencrypt+x509+plain' if VEncrypt is used with x509 and plain
text auth
• 'vencrypt+tls+sasl' if VEncrypt is used with TLS and SASL auth
• 'vencrypt+x509+sasl' if VEncrypt is used with x509 and SASL
auth
clients: array of VncClientInfo (optional)
a list of VncClientInfo of all currently connected clients
Since
0.14
If
CONFIG_VNC
VncPrimaryAuth (Enum)
vnc primary authentication method.
Values
none Not documented
vnc Not documented
ra2 Not documented
ra2ne Not documented
tight Not documented
ultra Not documented
tls Not documented
vencrypt
Not documented
sasl Not documented
Since
2.3
If
CONFIG_VNC
VncVencryptSubAuth (Enum)
vnc sub authentication method with vencrypt.
Values
plain Not documented
tls-none
Not documented
x509-none
Not documented
tls-vnc
Not documented
x509-vnc
Not documented
tls-plain
Not documented
x509-plain
Not documented
tls-sasl
Not documented
x509-sasl
Not documented
Since
2.3
If
CONFIG_VNC
VncServerInfo2 (Object)
The network connection information for server
Members
auth: VncPrimaryAuth
The current authentication type used by the servers
vencrypt: VncVencryptSubAuth (optional)
The vencrypt sub authentication type used by the servers, only
specified in case auth == vencrypt.
The members of VncBasicInfo
Since
2.9
If
CONFIG_VNC
VncInfo2 (Object)
Information about a vnc server
Members
id: string
vnc server name.
server: array of VncServerInfo2
A list of VncBasincInfo describing all listening sockets. The
list can be empty (in case the vnc server is disabled). It also
may have multiple entries: normal + websocket, possibly also
ipv4 + ipv6 in the future.
clients: array of VncClientInfo
A list of VncClientInfo of all currently connected clients. The
list can be empty, for obvious reasons.
auth: VncPrimaryAuth
The current authentication type used by the non-websockets
servers
vencrypt: VncVencryptSubAuth (optional)
The vencrypt authentication type used by the servers, only spec-
ified in case auth == vencrypt.
display: string (optional)
The display device the vnc server is linked to.
Since
2.3
If
CONFIG_VNC
query-vnc (Command)
Returns information about the current VNC server
Returns
VncInfo
Since
0.14
Example
-> { "execute": "query-vnc" }
<- { "return": {
"enabled":true,
"host":"0.0.0.0",
"service":"50402",
"auth":"vnc",
"family":"ipv4",
"clients":[
{
"host":"127.0.0.1",
"service":"50401",
"family":"ipv4",
"websocket":false
}
]
}
}
If
CONFIG_VNC
query-vnc-servers (Command)
Returns a list of vnc servers. The list can be empty.
Returns
a list of VncInfo2
Since
2.3
If
CONFIG_VNC
change-vnc-password (Command)
Change the VNC server password.
Arguments
password: string
the new password to use with VNC authentication
Since
1.1
Notes
An empty password in this command will set the password to the empty
string. Existing clients are unaffected by executing this command.
If
CONFIG_VNC
VNC_CONNECTED (Event)
Emitted when a VNC client establishes a connection
Arguments
server: VncServerInfo
server information
client: VncBasicInfo
client information
Note
This event is emitted before any authentication takes place, thus the
authentication ID is not provided
Since
0.13
Example
<- { "event": "VNC_CONNECTED",
"data": {
"server": { "auth": "sasl", "family": "ipv4", "websocket": false,
"service": "5901", "host": "0.0.0.0" },
"client": { "family": "ipv4", "service": "58425",
"host": "127.0.0.1", "websocket": false } },
"timestamp": { "seconds": 1262976601, "microseconds": 975795 } }
If
CONFIG_VNC
VNC_INITIALIZED (Event)
Emitted after authentication takes place (if any) and the VNC session
is made active
Arguments
server: VncServerInfo
server information
client: VncClientInfo
client information
Since
0.13
Example
<- { "event": "VNC_INITIALIZED",
"data": {
"server": { "auth": "sasl", "family": "ipv4", "websocket": false,
"service": "5901", "host": "0.0.0.0"},
"client": { "family": "ipv4", "service": "46089", "websocket": false,
"host": "127.0.0.1", "sasl_username": "luiz" } },
"timestamp": { "seconds": 1263475302, "microseconds": 150772 } }
If
CONFIG_VNC
VNC_DISCONNECTED (Event)
Emitted when the connection is closed
Arguments
server: VncServerInfo
server information
client: VncClientInfo
client information
Since
0.13
Example
<- { "event": "VNC_DISCONNECTED",
"data": {
"server": { "auth": "sasl", "family": "ipv4", "websocket": false,
"service": "5901", "host": "0.0.0.0" },
"client": { "family": "ipv4", "service": "58425", "websocket": false,
"host": "127.0.0.1", "sasl_username": "luiz" } },
"timestamp": { "seconds": 1262976601, "microseconds": 975795 } }
If
CONFIG_VNC
INPUT
MouseInfo (Object)
Information about a mouse device.
Members
name: string
the name of the mouse device
index: int
the index of the mouse device
current: boolean
true if this device is currently receiving mouse events
absolute: boolean
true if this device supports absolute coordinates as input
Since
0.14
query-mice (Command)
Returns information about each active mouse device
Returns
a list of MouseInfo for each device
Since
0.14
Example
-> { "execute": "query-mice" }
<- { "return": [
{
"name":"QEMU Microsoft Mouse",
"index":0,
"current":false,
"absolute":false
},
{
"name":"QEMU PS/2 Mouse",
"index":1,
"current":true,
"absolute":true
}
]
}
QKeyCode (Enum)
An enumeration of key name.
This is used by the send-key command.
Values
unmapped
since 2.0
pause since 2.0
ro since 2.4
kp_comma
since 2.4
kp_equals
since 2.6
power since 2.6
hiragana
since 2.9
henkan since 2.9
yen since 2.9
sleep since 2.10
wake since 2.10
audionext
since 2.10
audioprev
since 2.10
audiostop
since 2.10
audioplay
since 2.10
audiomute
since 2.10
volumeup
since 2.10
volumedown
since 2.10
mediaselect
since 2.10
mail since 2.10
calculator
since 2.10
computer
since 2.10
ac_home
since 2.10
ac_back
since 2.10
ac_forward
since 2.10
ac_refresh
since 2.10
ac_bookmarks
since 2.10
muhenkan
since 2.12
katakanahiragana
since 2.12
lang1 since 6.1
lang2 since 6.1
shift Not documented
shift_r
Not documented
alt Not documented
alt_r Not documented
ctrl Not documented
ctrl_r Not documented
menu Not documented
esc Not documented
1 Not documented
2 Not documented
3 Not documented
4 Not documented
5 Not documented
6 Not documented
7 Not documented
8 Not documented
9 Not documented
0 Not documented
minus Not documented
equal Not documented
backspace
Not documented
tab Not documented
q Not documented
w Not documented
e Not documented
r Not documented
t Not documented
y Not documented
u Not documented
i Not documented
o Not documented
p Not documented
bracket_left
Not documented
bracket_right
Not documented
ret Not documented
a Not documented
s Not documented
d Not documented
f Not documented
g Not documented
h Not documented
j Not documented
k Not documented
l Not documented
semicolon
Not documented
apostrophe
Not documented
grave_accent
Not documented
backslash
Not documented
z Not documented
x Not documented
c Not documented
v Not documented
b Not documented
n Not documented
m Not documented
comma Not documented
dot Not documented
slash Not documented
asterisk
Not documented
spc Not documented
caps_lock
Not documented
f1 Not documented
f2 Not documented
f3 Not documented
f4 Not documented
f5 Not documented
f6 Not documented
f7 Not documented
f8 Not documented
f9 Not documented
f10 Not documented
num_lock
Not documented
scroll_lock
Not documented
kp_divide
Not documented
kp_multiply
Not documented
kp_subtract
Not documented
kp_add Not documented
kp_enter
Not documented
kp_decimal
Not documented
sysrq Not documented
kp_0 Not documented
kp_1 Not documented
kp_2 Not documented
kp_3 Not documented
kp_4 Not documented
kp_5 Not documented
kp_6 Not documented
kp_7 Not documented
kp_8 Not documented
kp_9 Not documented
less Not documented
f11 Not documented
f12 Not documented
print Not documented
home Not documented
pgup Not documented
pgdn Not documented
end Not documented
left Not documented
up Not documented
down Not documented
right Not documented
insert Not documented
delete Not documented
stop Not documented
again Not documented
props Not documented
undo Not documented
front Not documented
copy Not documented
open Not documented
paste Not documented
find Not documented
cut Not documented
lf Not documented
help Not documented
meta_l Not documented
meta_r Not documented
compose
Not documented
'sysrq' was mistakenly added to hack around the fact that the ps2
driver was not generating correct scancodes sequences when 'alt+print'
was pressed. This flaw is now fixed and the 'sysrq' key serves no fur-
ther purpose. Any further use of 'sysrq' will be transparently changed
to 'print', so they are effectively synonyms.
Since
1.3
KeyValueKind (Enum)
Values
number Not documented
qcode Not documented
Since
1.3
IntWrapper (Object)
Members
data: int
Not documented
Since
1.3
QKeyCodeWrapper (Object)
Members
data: QKeyCode
Not documented
Since
1.3
KeyValue (Object)
Represents a keyboard key.
Members
type: KeyValueKind
Not documented
The members of IntWrapper when type is "number"
The members of QKeyCodeWrapper when type is "qcode"
Since
1.3
send-key (Command)
Send keys to guest.
Arguments
keys: array of KeyValue
An array of KeyValue elements. All KeyValues in this array are
simultaneously sent to the guest. A KeyValue.number value is
sent directly to the guest, while KeyValue.qcode must be a valid
QKeyCode value
hold-time: int (optional)
time to delay key up events, milliseconds. Defaults to 100
Returns
• Nothing on success
• If key is unknown or redundant, InvalidParameter
Since
1.3
Example
-> { "execute": "send-key",
"arguments": { "keys": [ { "type": "qcode", "data": "ctrl" },
{ "type": "qcode", "data": "alt" },
{ "type": "qcode", "data": "delete" } ] } }
<- { "return": {} }
InputButton (Enum)
Button of a pointer input device (mouse, tablet).
Values
side front side button of a 5-button mouse (since 2.9)
extra rear side button of a 5-button mouse (since 2.9)
left Not documented
middle Not documented
right Not documented
wheel-up
Not documented
wheel-down
Not documented
wheel-left
Not documented
wheel-right
Not documented
Since
2.0
InputAxis (Enum)
Position axis of a pointer input device (mouse, tablet).
Values
x Not documented
y Not documented
Since
2.0
InputKeyEvent (Object)
Keyboard input event.
Members
key: KeyValue
Which key this event is for.
down: boolean
True for key-down and false for key-up events.
Since
2.0
InputBtnEvent (Object)
Pointer button input event.
Members
button: InputButton
Which button this event is for.
down: boolean
True for key-down and false for key-up events.
Since
2.0
InputMoveEvent (Object)
Pointer motion input event.
Members
axis: InputAxis
Which axis is referenced by value.
value: int
Pointer position. For absolute coordinates the valid range is 0
-> 0x7ffff
Since
2.0
InputEventKind (Enum)
Values
key Not documented
btn Not documented
rel Not documented
abs Not documented
Since
2.0
InputKeyEventWrapper (Object)
Members
data: InputKeyEvent
Not documented
Since
2.0
InputBtnEventWrapper (Object)
Members
data: InputBtnEvent
Not documented
Since
2.0
InputMoveEventWrapper (Object)
Members
data: InputMoveEvent
Not documented
Since
2.0
InputEvent (Object)
Input event union.
Members
type: InputEventKind
the input type, one of:
• 'key': Input event of Keyboard
• 'btn': Input event of pointer buttons
• 'rel': Input event of relative pointer motion
• 'abs': Input event of absolute pointer motion
The members of InputKeyEventWrapper when type is "key"
The members of InputBtnEventWrapper when type is "btn"
The members of InputMoveEventWrapper when type is "rel"
The members of InputMoveEventWrapper when type is "abs"
Since
2.0
input-send-event (Command)
Send input event(s) to guest.
The device and head parameters can be used to send the input event to
specific input devices in case (a) multiple input devices of the same
kind are added to the virtual machine and (b) you have configured input
routing (see docs/multiseat.txt) for those input devices. The parame-
ters work exactly like the device and head properties of input devices.
If device is missing, only devices that have no input routing config
are admissible. If device is specified, both input devices with and
without input routing config are admissible, but devices with input
routing config take precedence.
Arguments
device: string (optional)
display device to send event(s) to.
head: int (optional)
head to send event(s) to, in case the display device supports
multiple scanouts.
events: array of InputEvent
List of InputEvent union.
Returns
Nothing on success.
Since
2.6
Note
The consoles are visible in the qom tree, under /backend/console[$in-
dex]. They have a device link and head property, so it is possible to
map which console belongs to which device and display.
Example
1. Press left mouse button.
-> { "execute": "input-send-event",
"arguments": { "device": "video0",
"events": [ { "type": "btn",
"data" : { "down": true, "button": "left" } } ] } }
<- { "return": {} }
-> { "execute": "input-send-event",
"arguments": { "device": "video0",
"events": [ { "type": "btn",
"data" : { "down": false, "button": "left" } } ] } }
<- { "return": {} }
2. Press ctrl-alt-del.
-> { "execute": "input-send-event",
"arguments": { "events": [
{ "type": "key", "data" : { "down": true,
"key": {"type": "qcode", "data": "ctrl" } } },
{ "type": "key", "data" : { "down": true,
"key": {"type": "qcode", "data": "alt" } } },
{ "type": "key", "data" : { "down": true,
"key": {"type": "qcode", "data": "delete" } } } ] } }
<- { "return": {} }
3. Move mouse pointer to absolute coordinates (20000, 400).
-> { "execute": "input-send-event" ,
"arguments": { "events": [
{ "type": "abs", "data" : { "axis": "x", "value" : 20000 } },
{ "type": "abs", "data" : { "axis": "y", "value" : 400 } } ] } }
<- { "return": {} }
DisplayGTK (Object)
GTK display options.
Members
grab-on-hover: boolean (optional)
Grab keyboard input on mouse hover.
zoom-to-fit: boolean (optional)
Zoom guest display to fit into the host window. When turned off
the host window will be resized instead. In case the display
device can notify the guest on window resizes (virtio-gpu) this
will default to "on", assuming the guest will resize the display
to match the window size then. Otherwise it defaults to "off".
Since 3.1
show-tabs: boolean (optional)
Display the tab bar for switching between the various graphical
interfaces (e.g. VGA and virtual console character devices) by
default. Since 7.1
show-menubar: boolean (optional)
Display the main window menubar. Defaults to "on". Since 8.0
Since
2.12
DisplayEGLHeadless (Object)
EGL headless display options.
Members
rendernode: string (optional)
Which DRM render node should be used. Default is the first
available node on the host.
Since
3.1
DisplayDBus (Object)
DBus display options.
Members
addr: string (optional)
The D-Bus bus address (default to the session bus).
rendernode: string (optional)
Which DRM render node should be used. Default is the first
available node on the host.
p2p: boolean (optional)
Whether to use peer-to-peer connections (accepted through
add_client).
audiodev: string (optional)
Use the specified DBus audiodev to export audio.
Since
7.0
DisplayGLMode (Enum)
Display OpenGL mode.
Values
off Disable OpenGL (default).
on Use OpenGL, pick context type automatically. Would better be
named 'auto' but is called 'on' for backward compatibility with
bool type.
core Use OpenGL with Core (desktop) Context.
es Use OpenGL with ES (embedded systems) Context.
Since
3.0
DisplayCurses (Object)
Curses display options.
Members
charset: string (optional)
Font charset used by guest (default: CP437).
Since
4.0
DisplayCocoa (Object)
Cocoa display options.
Members
left-command-key: boolean (optional)
Enable/disable forwarding of left command key to guest. Allows
command-tab window switching on the host without sending this
key to the guest when "off". Defaults to "on"
full-grab: boolean (optional)
Capture all key presses, including system combos. This requires
accessibility permissions, since it performs a global grab on
key events. (default: off) See
https://support.apple.com/en-in/guide/mac-help/mh32356/mac
swap-opt-cmd: boolean (optional)
Swap the Option and Command keys so that their key codes match
their position on non-Mac keyboards and you can use Meta/Super
and Alt where you expect them. (default: off)
Since
7.0
HotKeyMod (Enum)
Set of modifier keys that need to be held for shortcut key actions.
Values
lctrl-lalt
Not documented
lshift-lctrl-lalt
Not documented
rctrl Not documented
Since
7.1
DisplaySDL (Object)
SDL2 display options.
Members
grab-mod: HotKeyMod (optional)
Modifier keys that should be pressed together with the "G" key
to release the mouse grab.
Since
7.1
DisplayType (Enum)
Display (user interface) type.
Values
default
The default user interface, selecting from the first available
of gtk, sdl, cocoa, and vnc.
none No user interface or video output display. The guest will still
see an emulated graphics card, but its output will not be dis-
played to the QEMU user.
gtk (If: CONFIG_GTK)
The GTK user interface.
sdl (If: CONFIG_SDL)
The SDL user interface.
egl-headless (If: CONFIG_OPENGL and CONFIG_GBM)
No user interface, offload GL operations to a local DRI device.
Graphical display need to be paired with VNC or Spice. (Since
3.1)
curses (If: CONFIG_CURSES)
Display video output via curses. For graphics device models
which support a text mode, QEMU can display this output using a
curses/ncurses interface. Nothing is displayed when the graphics
device is in graphical mode or if the graphics device does not
support a text mode. Generally only the VGA device models sup-
port text mode.
cocoa (If: CONFIG_COCOA)
The Cocoa user interface.
spice-app (If: CONFIG_SPICE)
Set up a Spice server and run the default associated application
to connect to it. The server will redirect the serial console
and QEMU monitors. (Since 4.0)
dbus (If: CONFIG_DBUS_DISPLAY)
Start a D-Bus service for the display. (Since 7.0)
Since
2.12
DisplayOptions (Object)
Display (user interface) options.
Members
type: DisplayType
Which DisplayType qemu should use.
full-screen: boolean (optional)
Start user interface in fullscreen mode (default: off).
window-close: boolean (optional)
Allow to quit qemu with window close button (default: on).
show-cursor: boolean (optional)
Force showing the mouse cursor (default: off). (since: 5.0)
gl: DisplayGLMode (optional)
Enable OpenGL support (default: off).
The members of DisplayGTK when type is "gtk" (If: CONFIG_GTK)
The members of DisplayCocoa when type is "cocoa" (If: CONFIG_COCOA)
The members of DisplayCurses when type is "curses" (If: CONFIG_CURSES)
The members of DisplayEGLHeadless when type is "egl-headless" (If: CON-
FIG_OPENGL and CONFIG_GBM)
The members of DisplayDBus when type is "dbus" (If: CONFIG_DBUS_DIS-
PLAY)
The members of DisplaySDL when type is "sdl" (If: CONFIG_SDL)
Since
2.12
query-display-options (Command)
Returns information about display configuration
Returns
DisplayOptions
Since
3.1
DisplayReloadType (Enum)
Available DisplayReload types.
Values
vnc VNC display
Since
6.0
DisplayReloadOptionsVNC (Object)
Specify the VNC reload options.
Members
tls-certs: boolean (optional)
reload tls certs or not.
Since
6.0
DisplayReloadOptions (Object)
Options of the display configuration reload.
Members
type: DisplayReloadType
Specify the display type.
The members of DisplayReloadOptionsVNC when type is "vnc"
Since
6.0
display-reload (Command)
Reload display configuration.
Arguments
The members of DisplayReloadOptions
Returns
Nothing on success.
Since
6.0
Example
-> { "execute": "display-reload",
"arguments": { "type": "vnc", "tls-certs": true } }
<- { "return": {} }
DisplayUpdateType (Enum)
Available DisplayUpdate types.
Values
vnc VNC display
Since
7.1
DisplayUpdateOptionsVNC (Object)
Specify the VNC reload options.
Members
addresses: array of SocketAddress (optional)
If specified, change set of addresses to listen for connections.
Addresses configured for websockets are not touched.
Since
7.1
DisplayUpdateOptions (Object)
Options of the display configuration reload.
Members
type: DisplayUpdateType
Specify the display type.
The members of DisplayUpdateOptionsVNC when type is "vnc"
Since
7.1
display-update (Command)
Update display configuration.
Arguments
The members of DisplayUpdateOptions
Returns
Nothing on success.
Since
7.1
Example
-> { "execute": "display-update",
"arguments": { "type": "vnc", "addresses":
[ { "type": "inet", "host": "0.0.0.0",
"port": "5901" } ] } }
<- { "return": {} }
USER AUTHORIZATION
QAuthZListPolicy (Enum)
The authorization policy result
Values
deny deny access
allow allow access
Since
4.0
QAuthZListFormat (Enum)
The authorization policy match format
Values
exact an exact string match
glob string with ? and * shell wildcard support
Since
4.0
QAuthZListRule (Object)
A single authorization rule.
Members
match: string
a string or glob to match against a user identity
policy: QAuthZListPolicy
the result to return if match evaluates to true
format: QAuthZListFormat (optional)
the format of the match rule (default 'exact')
Since
4.0
AuthZListProperties (Object)
Properties for authz-list objects.
Members
policy: QAuthZListPolicy (optional)
Default policy to apply when no rule matches (default: deny)
rules: array of QAuthZListRule (optional)
Authorization rules based on matching user
Since
4.0
AuthZListFileProperties (Object)
Properties for authz-listfile objects.
Members
filename: string
File name to load the configuration from. The file must contain
valid JSON for AuthZListProperties.
refresh: boolean (optional)
If true, inotify is used to monitor the file, automatically
reloading changes. If an error occurs during reloading, all au-
thorizations will fail until the file is next successfully
loaded. (default: true if the binary was built with CONFIG_INO-
TIFY1, false otherwise)
Since
4.0
AuthZPAMProperties (Object)
Properties for authz-pam objects.
Members
service: string
PAM service name to use for authorization
Since
4.0
AuthZSimpleProperties (Object)
Properties for authz-simple objects.
Members
identity: string
Identifies the allowed user. Its format depends on the network
service that authorization object is associated with. For autho-
rizing based on TLS x509 certificates, the identity must be the
x509 distinguished name.
Since
4.0
MIGRATION
MigrationStats (Object)
Detailed migration status.
Members
transferred: int
amount of bytes already transferred to the target VM
remaining: int
amount of bytes remaining to be transferred to the target VM
total: int
total amount of bytes involved in the migration process
duplicate: int
number of duplicate (zero) pages (since 1.2)
skipped: int
number of skipped zero pages (since 1.5)
normal: int
number of normal pages (since 1.2)
normal-bytes: int
number of normal bytes sent (since 1.2)
dirty-pages-rate: int
number of pages dirtied by second by the guest (since 1.3)
mbps: number
throughput in megabits/sec. (since 1.6)
dirty-sync-count: int
number of times that dirty ram was synchronized (since 2.1)
postcopy-requests: int
The number of page requests received from the destination (since
2.7)
page-size: int
The number of bytes per page for the various page-based statis-
tics (since 2.10)
multifd-bytes: int
The number of bytes sent through multifd (since 3.0)
pages-per-second: int
the number of memory pages transferred per second (Since 4.0)
precopy-bytes: int
The number of bytes sent in the pre-copy phase (since 7.0).
downtime-bytes: int
The number of bytes sent while the guest is paused (since 7.0).
postcopy-bytes: int
The number of bytes sent during the post-copy phase (since 7.0).
dirty-sync-missed-zero-copy: int
Number of times dirty RAM synchronization could not avoid copy-
ing dirty pages. This is between 0 and dirty-sync-count * mul-
tifd-channels. (since 7.1)
Since
0.14
XBZRLECacheStats (Object)
Detailed XBZRLE migration cache statistics
Members
cache-size: int
XBZRLE cache size
bytes: int
amount of bytes already transferred to the target VM
pages: int
amount of pages transferred to the target VM
cache-miss: int
number of cache miss
cache-miss-rate: number
rate of cache miss (since 2.1)
encoding-rate: number
rate of encoded bytes (since 5.1)
overflow: int
number of overflows
Since
1.2
CompressionStats (Object)
Detailed migration compression statistics
Members
pages: int
amount of pages compressed and transferred to the target VM
busy: int
count of times that no free thread was available to compress
data
busy-rate: number
rate of thread busy
compressed-size: int
amount of bytes after compression
compression-rate: number
rate of compressed size
Since
3.1
MigrationStatus (Enum)
An enumeration of migration status.
Values
none no migration has ever happened.
setup migration process has been initiated.
cancelling
in the process of cancelling migration.
cancelled
cancelling migration is finished.
active in the process of doing migration.
postcopy-active
like active, but now in postcopy mode. (since 2.5)
postcopy-paused
during postcopy but paused. (since 3.0)
postcopy-recover
trying to recover from a paused postcopy. (since 3.0)
completed
migration is finished.
failed some error occurred during migration process.
colo VM is in the process of fault tolerance, VM can not get into
this state unless colo capability is enabled for migration.
(since 2.8)
pre-switchover
Paused before device serialisation. (since 2.11)
device During device serialisation when pause-before-switchover is en-
abled (since 2.11)
wait-unplug
wait for device unplug request by guest OS to be completed.
(since 4.2)
Since
2.3
VfioStats (Object)
Detailed VFIO devices migration statistics
Members
transferred: int
amount of bytes transferred to the target VM by VFIO devices
Since
5.2
MigrationInfo (Object)
Information about current migration process.
Members
status: MigrationStatus (optional)
MigrationStatus describing the current migration status. If
this field is not returned, no migration process has been initi-
ated
ram: MigrationStats (optional)
MigrationStats containing detailed migration status, only re-
turned if status is 'active' or 'completed'(since 1.2)
disk: MigrationStats (optional)
MigrationStats containing detailed disk migration status, only
returned if status is 'active' and it is a block migration
xbzrle-cache: XBZRLECacheStats (optional)
XBZRLECacheStats containing detailed XBZRLE migration statis-
tics, only returned if XBZRLE feature is on and status is 'ac-
tive' or 'completed' (since 1.2)
total-time: int (optional)
total amount of milliseconds since migration started. If migra-
tion has ended, it returns the total migration time. (since 1.2)
downtime: int (optional)
only present when migration finishes correctly total downtime in
milliseconds for the guest. (since 1.3)
expected-downtime: int (optional)
only present while migration is active expected downtime in mil-
liseconds for the guest in last walk of the dirty bitmap. (since
1.3)
setup-time: int (optional)
amount of setup time in milliseconds before the iterations begin
but after the QMP command is issued. This is designed to provide
an accounting of any activities (such as RDMA pinning) which may
be expensive, but do not actually occur during the iterative mi-
gration rounds themselves. (since 1.6)
cpu-throttle-percentage: int (optional)
percentage of time guest cpus are being throttled during
auto-converge. This is only present when auto-converge has
started throttling guest cpus. (Since 2.7)
error-desc: string (optional)
the human readable error description string, when status is
'failed'. Clients should not attempt to parse the error strings.
(Since 2.7)
postcopy-blocktime: int (optional)
total time when all vCPU were blocked during postcopy live mi-
gration. This is only present when the postcopy-blocktime migra-
tion capability is enabled. (Since 3.0)
postcopy-vcpu-blocktime: array of int (optional)
list of the postcopy blocktime per vCPU. This is only present
when the postcopy-blocktime migration capability is enabled.
(Since 3.0)
compression: CompressionStats (optional)
migration compression statistics, only returned if compression
feature is on and status is 'active' or 'completed' (Since 3.1)
socket-address: array of SocketAddress (optional)
Only used for tcp, to know what the real port is (Since 4.0)
vfio: VfioStats (optional)
VfioStats containing detailed VFIO devices migration statistics,
only returned if VFIO device is present, migration is supported
by all VFIO devices and status is 'active' or 'completed' (since
5.2)
blocked-reasons: array of string (optional)
A list of reasons an outgoing migration is blocked. Present and
non-empty when migration is blocked. (since 6.0)
Since
0.14
query-migrate (Command)
Returns information about current migration process. If migration is
active there will be another json-object with RAM migration status and
if block migration is active another one with block migration status.
Returns
MigrationInfo
Since
0.14
Example
1. Before the first migration
-> { "execute": "query-migrate" }
<- { "return": {} }
2. Migration is done and has succeeded
-> { "execute": "query-migrate" }
<- { "return": {
"status": "completed",
"total-time":12345,
"setup-time":12345,
"downtime":12345,
"ram":{
"transferred":123,
"remaining":123,
"total":246,
"duplicate":123,
"normal":123,
"normal-bytes":123456,
"dirty-sync-count":15
}
}
}
3. Migration is done and has failed
-> { "execute": "query-migrate" }
<- { "return": { "status": "failed" } }
4. Migration is being performed and is not a block migration:
-> { "execute": "query-migrate" }
<- {
"return":{
"status":"active",
"total-time":12345,
"setup-time":12345,
"expected-downtime":12345,
"ram":{
"transferred":123,
"remaining":123,
"total":246,
"duplicate":123,
"normal":123,
"normal-bytes":123456,
"dirty-sync-count":15
}
}
}
5. Migration is being performed and is a block migration:
-> { "execute": "query-migrate" }
<- {
"return":{
"status":"active",
"total-time":12345,
"setup-time":12345,
"expected-downtime":12345,
"ram":{
"total":1057024,
"remaining":1053304,
"transferred":3720,
"duplicate":123,
"normal":123,
"normal-bytes":123456,
"dirty-sync-count":15
},
"disk":{
"total":20971520,
"remaining":20880384,
"transferred":91136
}
}
}
6. Migration is being performed and XBZRLE is active:
-> { "execute": "query-migrate" }
<- {
"return":{
"status":"active",
"total-time":12345,
"setup-time":12345,
"expected-downtime":12345,
"ram":{
"total":1057024,
"remaining":1053304,
"transferred":3720,
"duplicate":10,
"normal":3333,
"normal-bytes":3412992,
"dirty-sync-count":15
},
"xbzrle-cache":{
"cache-size":67108864,
"bytes":20971520,
"pages":2444343,
"cache-miss":2244,
"cache-miss-rate":0.123,
"encoding-rate":80.1,
"overflow":34434
}
}
}
MigrationCapability (Enum)
Migration capabilities enumeration
Values
xbzrle Migration supports xbzrle (Xor Based Zero Run Length Encoding).
This feature allows us to minimize migration traffic for certain
work loads, by sending compressed difference of the pages
rdma-pin-all
Controls whether or not the entire VM memory footprint is
mlock()'d on demand or all at once. Refer to docs/rdma.txt for
usage. Disabled by default. (since 2.0)
zero-blocks
During storage migration encode blocks of zeroes efficiently.
This essentially saves 1MB of zeroes per block on the wire. En-
abling requires source and target VM to support this feature. To
enable it is sufficient to enable the capability on the source
VM. The feature is disabled by default. (since 1.6)
compress
Use multiple compression threads to accelerate live migration.
This feature can help to reduce the migration traffic, by send-
ing compressed pages. Please note that if compress and xbzrle
are both on, compress only takes effect in the ram bulk stage,
after that, it will be disabled and only xbzrle takes effect,
this can help to minimize migration traffic. The feature is dis-
abled by default. (since 2.4 )
events generate events for each migration state change (since 2.4 )
auto-converge
If enabled, QEMU will automatically throttle down the guest to
speed up convergence of RAM migration. (since 1.6)
postcopy-ram
Start executing on the migration target before all of RAM has
been migrated, pulling the remaining pages along as needed. The
capacity must have the same setting on both source and target or
migration will not even start. NOTE: If the migration fails dur-
ing postcopy the VM will fail. (since 2.6)
x-colo If enabled, migration will never end, and the state of the VM on
the primary side will be migrated continuously to the VM on sec-
ondary side, this process is called COarse-Grain LOck Stepping
(COLO) for Non-stop Service. (since 2.8)
release-ram
if enabled, qemu will free the migrated ram pages on the source
during postcopy-ram migration. (since 2.9)
block If enabled, QEMU will also migrate the contents of all block de-
vices. Default is disabled. A possible alternative uses mirror
jobs to a builtin NBD server on the destination, which offers
more flexibility. (Since 2.10)
return-path
If enabled, migration will use the return path even for precopy.
(since 2.10)
pause-before-switchover
Pause outgoing migration before serialising device state and be-
fore disabling block IO (since 2.11)
multifd
Use more than one fd for migration (since 4.0)
dirty-bitmaps
If enabled, QEMU will migrate named dirty bitmaps. (since 2.12)
postcopy-blocktime
Calculate downtime for postcopy live migration (since 3.0)
late-block-activate
If enabled, the destination will not activate block devices (and
thus take locks) immediately at the end of migration. (since
3.0)
x-ignore-shared
If enabled, QEMU will not migrate shared memory (since 4.0)
validate-uuid
Send the UUID of the source to allow the destination to ensure
it is the same. (since 4.2)
background-snapshot
If enabled, the migration stream will be a snapshot of the VM
exactly at the point when the migration procedure starts. The VM
RAM is saved with running VM. (since 6.0)
zero-copy-send
Controls behavior on sending memory pages on migration. When
true, enables a zero-copy mechanism for sending memory pages, if
host supports it. Requires that QEMU be permitted to use locked
memory for guest RAM pages. (since 7.1)
postcopy-preempt
If enabled, the migration process will allow postcopy requests
to preempt precopy stream, so postcopy requests will be handled
faster. This is a performance feature and should not affect the
correctness of postcopy migration. (since 7.1)
Features
unstable
Members x-colo and x-ignore-shared are experimental.
Since
1.2
MigrationCapabilityStatus (Object)
Migration capability information
Members
capability: MigrationCapability
capability enum
state: boolean
capability state bool
Since
1.2
migrate-set-capabilities (Command)
Enable/Disable the following migration capabilities (like xbzrle)
Arguments
capabilities: array of MigrationCapabilityStatus
json array of capability modifications to make
Since
1.2
Example
-> { "execute": "migrate-set-capabilities" , "arguments":
{ "capabilities": [ { "capability": "xbzrle", "state": true } ] } }
query-migrate-capabilities (Command)
Returns information about the current migration capabilities status
Returns
MigrationCapabilitiesStatus
Since
1.2
Example
-> { "execute": "query-migrate-capabilities" }
<- { "return": [
{"state": false, "capability": "xbzrle"},
{"state": false, "capability": "rdma-pin-all"},
{"state": false, "capability": "auto-converge"},
{"state": false, "capability": "zero-blocks"},
{"state": false, "capability": "compress"},
{"state": true, "capability": "events"},
{"state": false, "capability": "postcopy-ram"},
{"state": false, "capability": "x-colo"}
]}
MultiFDCompression (Enum)
An enumeration of multifd compression methods.
Values
none no compression.
zlib use zlib compression method.
zstd (If: CONFIG_ZSTD)
use zstd compression method.
Since
5.0
BitmapMigrationBitmapAliasTransform (Object)
Members
persistent: boolean (optional)
If present, the bitmap will be made persistent or transient de-
pending on this parameter.
Since
6.0
BitmapMigrationBitmapAlias (Object)
Members
name: string
The name of the bitmap.
alias: string
An alias name for migration (for example the bitmap name on the
opposite site).
transform: BitmapMigrationBitmapAliasTransform (optional)
Allows the modification of the migrated bitmap. (since 6.0)
Since
5.2
BitmapMigrationNodeAlias (Object)
Maps a block node name and the bitmaps it has to aliases for dirty bit-
map migration.
Members
node-name: string
A block node name.
alias: string
An alias block node name for migration (for example the node
name on the opposite site).
bitmaps: array of BitmapMigrationBitmapAlias
Mappings for the bitmaps on this node.
Since
5.2
MigrationParameter (Enum)
Migration parameters enumeration
Values
announce-initial
Initial delay (in milliseconds) before sending the first an-
nounce (Since 4.0)
announce-max
Maximum delay (in milliseconds) between packets in the announce-
ment (Since 4.0)
announce-rounds
Number of self-announce packets sent after migration (Since 4.0)
announce-step
Increase in delay (in milliseconds) between subsequent packets
in the announcement (Since 4.0)
compress-level
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 9, where 0 means no
compression, 1 means the best compression speed, and 9 means
best compression ratio which will consume more CPU.
compress-threads
Set compression thread count to be used in live migration, the
compression thread count is an integer between 1 and 255.
compress-wait-thread
Controls behavior when all compression threads are currently
busy. If true (default), wait for a free compression thread to
become available; otherwise, send the page uncompressed. (Since
3.1)
decompress-threads
Set decompression thread count to be used in live migration, the
decompression thread count is an integer between 1 and 255. Usu-
ally, decompression is at least 4 times as fast as compression,
so set the decompress-threads to the number about 1/4 of com-
press-threads is adequate.
throttle-trigger-threshold
The ratio of bytes_dirty_period and bytes_xfer_period to trigger
throttling. It is expressed as percentage. The default value is
50. (Since 5.0)
cpu-throttle-initial
Initial percentage of time guest cpus are throttled when migra-
tion auto-converge is activated. The default value is 20. (Since
2.7)
cpu-throttle-increment
throttle percentage increase each time auto-converge detects
that migration is not making progress. The default value is 10.
(Since 2.7)
cpu-throttle-tailslow
Make CPU throttling slower at tail stage At the tail stage of
throttling, the Guest is very sensitive to CPU percentage while
the cpu-throttle -increment is excessive usually at tail stage.
If this parameter is true, we will compute the ideal CPU per-
centage used by the Guest, which may exactly make the dirty rate
match the dirty rate threshold. Then we will choose a smaller
throttle increment between the one specified by cpu-throttle-in-
crement and the one generated by ideal CPU percentage. There-
fore, it is compatible to traditional throttling, meanwhile the
throttle increment won't be excessive at tail stage. The de-
fault value is false. (Since 5.1)
tls-creds
ID of the 'tls-creds' object that provides credentials for es-
tablishing a TLS connection over the migration data channel. On
the outgoing side of the migration, the credentials must be for
a 'client' endpoint, while for the incoming side the credentials
must be for a 'server' endpoint. Setting this will enable TLS
for all migrations. The default is unset, resulting in unsecured
migration at the QEMU level. (Since 2.7)
tls-hostname
hostname of the target host for the migration. This is required
when using x509 based TLS credentials and the migration URI does
not already include a hostname. For example if using fd: or
exec: based migration, the hostname must be provided so that the
server's x509 certificate identity can be validated. (Since 2.7)
tls-authz
ID of the 'authz' object subclass that provides access control
checking of the TLS x509 certificate distinguished name. This
object is only resolved at time of use, so can be deleted and
recreated on the fly while the migration server is active. If
missing, it will default to denying access (Since 4.0)
max-bandwidth
to set maximum speed for migration. maximum speed in bytes per
second. (Since 2.8)
downtime-limit
set maximum tolerated downtime for migration. maximum downtime
in milliseconds (Since 2.8)
x-checkpoint-delay
The delay time (in ms) between two COLO checkpoints in periodic
mode. (Since 2.8)
block-incremental
Affects how much storage is migrated when the block migration
capability is enabled. When false, the entire storage backing
chain is migrated into a flattened image at the destination;
when true, only the active qcow2 layer is migrated and the des-
tination must already have access to the same backing chain as
was used on the source. (since 2.10)
multifd-channels
Number of channels used to migrate data in parallel. This is the
same number that the number of sockets used for migration. The
default value is 2 (since 4.0)
xbzrle-cache-size
cache size to be used by XBZRLE migration. It needs to be a
multiple of the target page size and a power of 2 (Since 2.11)
max-postcopy-bandwidth
Background transfer bandwidth during postcopy. Defaults to 0
(unlimited). In bytes per second. (Since 3.0)
max-cpu-throttle
maximum cpu throttle percentage. Defaults to 99. (Since 3.1)
multifd-compression
Which compression method to use. Defaults to none. (Since 5.0)
multifd-zlib-level
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 9, where 0 means no
compression, 1 means the best compression speed, and 9 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
multifd-zstd-level
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 20, where 0 means no
compression, 1 means the best compression speed, and 20 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
block-bitmap-mapping
Maps block nodes and bitmaps on them to aliases for the purpose
of dirty bitmap migration. Such aliases may for example be the
corresponding names on the opposite site. The mapping must be
one-to-one, but not necessarily complete: On the source, un-
mapped bitmaps and all bitmaps on unmapped nodes will be ig-
nored. On the destination, encountering an unmapped alias in
the incoming migration stream will result in a report, and all
further bitmap migration data will then be discarded. Note that
the destination does not know about bitmaps it does not receive,
so there is no limitation or requirement regarding the number of
bitmaps received, or how they are named, or on which nodes they
are placed. By default (when this parameter has never been
set), bitmap names are mapped to themselves. Nodes are mapped
to their block device name if there is one, and to their node
name otherwise. (Since 5.2)
Features
unstable
Member x-checkpoint-delay is experimental.
Since
2.4
MigrateSetParameters (Object)
Members
announce-initial: int (optional)
Initial delay (in milliseconds) before sending the first an-
nounce (Since 4.0)
announce-max: int (optional)
Maximum delay (in milliseconds) between packets in the announce-
ment (Since 4.0)
announce-rounds: int (optional)
Number of self-announce packets sent after migration (Since 4.0)
announce-step: int (optional)
Increase in delay (in milliseconds) between subsequent packets
in the announcement (Since 4.0)
compress-level: int (optional)
compression level
compress-threads: int (optional)
compression thread count
compress-wait-thread: boolean (optional)
Controls behavior when all compression threads are currently
busy. If true (default), wait for a free compression thread to
become available; otherwise, send the page uncompressed. (Since
3.1)
decompress-threads: int (optional)
decompression thread count
throttle-trigger-threshold: int (optional)
The ratio of bytes_dirty_period and bytes_xfer_period to trigger
throttling. It is expressed as percentage. The default value is
50. (Since 5.0)
cpu-throttle-initial: int (optional)
Initial percentage of time guest cpus are throttled when migra-
tion auto-converge is activated. The default value is 20.
(Since 2.7)
cpu-throttle-increment: int (optional)
throttle percentage increase each time auto-converge detects
that migration is not making progress. The default value is 10.
(Since 2.7)
cpu-throttle-tailslow: boolean (optional)
Make CPU throttling slower at tail stage At the tail stage of
throttling, the Guest is very sensitive to CPU percentage while
the cpu-throttle -increment is excessive usually at tail stage.
If this parameter is true, we will compute the ideal CPU per-
centage used by the Guest, which may exactly make the dirty rate
match the dirty rate threshold. Then we will choose a smaller
throttle increment between the one specified by cpu-throttle-in-
crement and the one generated by ideal CPU percentage. There-
fore, it is compatible to traditional throttling, meanwhile the
throttle increment won't be excessive at tail stage. The de-
fault value is false. (Since 5.1)
tls-creds: StrOrNull (optional)
ID of the 'tls-creds' object that provides credentials for es-
tablishing a TLS connection over the migration data channel. On
the outgoing side of the migration, the credentials must be for
a 'client' endpoint, while for the incoming side the credentials
must be for a 'server' endpoint. Setting this to a non-empty
string enables TLS for all migrations. An empty string means
that QEMU will use plain text mode for migration, rather than
TLS (Since 2.9) Previously (since 2.7), this was reported by
omitting tls-creds instead.
tls-hostname: StrOrNull (optional)
hostname of the target host for the migration. This is required
when using x509 based TLS credentials and the migration URI does
not already include a hostname. For example if using fd: or
exec: based migration, the hostname must be provided so that the
server's x509 certificate identity can be validated. (Since 2.7)
An empty string means that QEMU will use the hostname associated
with the migration URI, if any. (Since 2.9) Previously (since
2.7), this was reported by omitting tls-hostname instead.
max-bandwidth: int (optional)
to set maximum speed for migration. maximum speed in bytes per
second. (Since 2.8)
downtime-limit: int (optional)
set maximum tolerated downtime for migration. maximum downtime
in milliseconds (Since 2.8)
x-checkpoint-delay: int (optional)
the delay time between two COLO checkpoints. (Since 2.8)
block-incremental: boolean (optional)
Affects how much storage is migrated when the block migration
capability is enabled. When false, the entire storage backing
chain is migrated into a flattened image at the destination;
when true, only the active qcow2 layer is migrated and the des-
tination must already have access to the same backing chain as
was used on the source. (since 2.10)
multifd-channels: int (optional)
Number of channels used to migrate data in parallel. This is the
same number that the number of sockets used for migration. The
default value is 2 (since 4.0)
xbzrle-cache-size: int (optional)
cache size to be used by XBZRLE migration. It needs to be a
multiple of the target page size and a power of 2 (Since 2.11)
max-postcopy-bandwidth: int (optional)
Background transfer bandwidth during postcopy. Defaults to 0
(unlimited). In bytes per second. (Since 3.0)
max-cpu-throttle: int (optional)
maximum cpu throttle percentage. The default value is 99.
(Since 3.1)
multifd-compression: MultiFDCompression (optional)
Which compression method to use. Defaults to none. (Since 5.0)
multifd-zlib-level: int (optional)
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 9, where 0 means no
compression, 1 means the best compression speed, and 9 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
multifd-zstd-level: int (optional)
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 20, where 0 means no
compression, 1 means the best compression speed, and 20 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
block-bitmap-mapping: array of BitmapMigrationNodeAlias (optional)
Maps block nodes and bitmaps on them to aliases for the purpose
of dirty bitmap migration. Such aliases may for example be the
corresponding names on the opposite site. The mapping must be
one-to-one, but not necessarily complete: On the source, un-
mapped bitmaps and all bitmaps on unmapped nodes will be ig-
nored. On the destination, encountering an unmapped alias in
the incoming migration stream will result in a report, and all
further bitmap migration data will then be discarded. Note that
the destination does not know about bitmaps it does not receive,
so there is no limitation or requirement regarding the number of
bitmaps received, or how they are named, or on which nodes they
are placed. By default (when this parameter has never been
set), bitmap names are mapped to themselves. Nodes are mapped
to their block device name if there is one, and to their node
name otherwise. (Since 5.2)
tls-authz: StrOrNull (optional)
Not documented
Features
unstable
Member x-checkpoint-delay is experimental.
Since
2.4
migrate-set-parameters (Command)
Set various migration parameters.
Arguments
The members of MigrateSetParameters
Since
2.4
Example
-> { "execute": "migrate-set-parameters" ,
"arguments": { "compress-level": 1 } }
MigrationParameters (Object)
The optional members aren't actually optional.
Members
announce-initial: int (optional)
Initial delay (in milliseconds) before sending the first an-
nounce (Since 4.0)
announce-max: int (optional)
Maximum delay (in milliseconds) between packets in the announce-
ment (Since 4.0)
announce-rounds: int (optional)
Number of self-announce packets sent after migration (Since 4.0)
announce-step: int (optional)
Increase in delay (in milliseconds) between subsequent packets
in the announcement (Since 4.0)
compress-level: int (optional)
compression level
compress-threads: int (optional)
compression thread count
compress-wait-thread: boolean (optional)
Controls behavior when all compression threads are currently
busy. If true (default), wait for a free compression thread to
become available; otherwise, send the page uncompressed. (Since
3.1)
decompress-threads: int (optional)
decompression thread count
throttle-trigger-threshold: int (optional)
The ratio of bytes_dirty_period and bytes_xfer_period to trigger
throttling. It is expressed as percentage. The default value is
50. (Since 5.0)
cpu-throttle-initial: int (optional)
Initial percentage of time guest cpus are throttled when migra-
tion auto-converge is activated. (Since 2.7)
cpu-throttle-increment: int (optional)
throttle percentage increase each time auto-converge detects
that migration is not making progress. (Since 2.7)
cpu-throttle-tailslow: boolean (optional)
Make CPU throttling slower at tail stage At the tail stage of
throttling, the Guest is very sensitive to CPU percentage while
the cpu-throttle -increment is excessive usually at tail stage.
If this parameter is true, we will compute the ideal CPU per-
centage used by the Guest, which may exactly make the dirty rate
match the dirty rate threshold. Then we will choose a smaller
throttle increment between the one specified by cpu-throttle-in-
crement and the one generated by ideal CPU percentage. There-
fore, it is compatible to traditional throttling, meanwhile the
throttle increment won't be excessive at tail stage. The de-
fault value is false. (Since 5.1)
tls-creds: string (optional)
ID of the 'tls-creds' object that provides credentials for es-
tablishing a TLS connection over the migration data channel. On
the outgoing side of the migration, the credentials must be for
a 'client' endpoint, while for the incoming side the credentials
must be for a 'server' endpoint. An empty string means that
QEMU will use plain text mode for migration, rather than TLS
(Since 2.7) Note: 2.8 reports this by omitting tls-creds in-
stead.
tls-hostname: string (optional)
hostname of the target host for the migration. This is required
when using x509 based TLS credentials and the migration URI does
not already include a hostname. For example if using fd: or
exec: based migration, the hostname must be provided so that the
server's x509 certificate identity can be validated. (Since 2.7)
An empty string means that QEMU will use the hostname associated
with the migration URI, if any. (Since 2.9) Note: 2.8 reports
this by omitting tls-hostname instead.
tls-authz: string (optional)
ID of the 'authz' object subclass that provides access control
checking of the TLS x509 certificate distinguished name. (Since
4.0)
max-bandwidth: int (optional)
to set maximum speed for migration. maximum speed in bytes per
second. (Since 2.8)
downtime-limit: int (optional)
set maximum tolerated downtime for migration. maximum downtime
in milliseconds (Since 2.8)
x-checkpoint-delay: int (optional)
the delay time between two COLO checkpoints. (Since 2.8)
block-incremental: boolean (optional)
Affects how much storage is migrated when the block migration
capability is enabled. When false, the entire storage backing
chain is migrated into a flattened image at the destination;
when true, only the active qcow2 layer is migrated and the des-
tination must already have access to the same backing chain as
was used on the source. (since 2.10)
multifd-channels: int (optional)
Number of channels used to migrate data in parallel. This is the
same number that the number of sockets used for migration. The
default value is 2 (since 4.0)
xbzrle-cache-size: int (optional)
cache size to be used by XBZRLE migration. It needs to be a
multiple of the target page size and a power of 2 (Since 2.11)
max-postcopy-bandwidth: int (optional)
Background transfer bandwidth during postcopy. Defaults to 0
(unlimited). In bytes per second. (Since 3.0)
max-cpu-throttle: int (optional)
maximum cpu throttle percentage. Defaults to 99. (Since 3.1)
multifd-compression: MultiFDCompression (optional)
Which compression method to use. Defaults to none. (Since 5.0)
multifd-zlib-level: int (optional)
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 9, where 0 means no
compression, 1 means the best compression speed, and 9 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
multifd-zstd-level: int (optional)
Set the compression level to be used in live migration, the com-
pression level is an integer between 0 and 20, where 0 means no
compression, 1 means the best compression speed, and 20 means
best compression ratio which will consume more CPU. Defaults to
1. (Since 5.0)
block-bitmap-mapping: array of BitmapMigrationNodeAlias (optional)
Maps block nodes and bitmaps on them to aliases for the purpose
of dirty bitmap migration. Such aliases may for example be the
corresponding names on the opposite site. The mapping must be
one-to-one, but not necessarily complete: On the source, un-
mapped bitmaps and all bitmaps on unmapped nodes will be ig-
nored. On the destination, encountering an unmapped alias in
the incoming migration stream will result in a report, and all
further bitmap migration data will then be discarded. Note that
the destination does not know about bitmaps it does not receive,
so there is no limitation or requirement regarding the number of
bitmaps received, or how they are named, or on which nodes they
are placed. By default (when this parameter has never been
set), bitmap names are mapped to themselves. Nodes are mapped
to their block device name if there is one, and to their node
name otherwise. (Since 5.2)
Features
unstable
Member x-checkpoint-delay is experimental.
Since
2.4
query-migrate-parameters (Command)
Returns information about the current migration parameters
Returns
MigrationParameters
Since
2.4
Example
-> { "execute": "query-migrate-parameters" }
<- { "return": {
"decompress-threads": 2,
"cpu-throttle-increment": 10,
"compress-threads": 8,
"compress-level": 1,
"cpu-throttle-initial": 20,
"max-bandwidth": 33554432,
"downtime-limit": 300
}
}
client_migrate_info (Command)
Set migration information for remote display. This makes the server
ask the client to automatically reconnect using the new parameters once
migration finished successfully. Only implemented for SPICE.
Arguments
protocol: string
must be "spice"
hostname: string
migration target hostname
port: int (optional)
spice tcp port for plaintext channels
tls-port: int (optional)
spice tcp port for tls-secured channels
cert-subject: string (optional)
server certificate subject
Since
0.14
Example
-> { "execute": "client_migrate_info",
"arguments": { "protocol": "spice",
"hostname": "virt42.lab.kraxel.org",
"port": 1234 } }
<- { "return": {} }
migrate-start-postcopy (Command)
Followup to a migration command to switch the migration to postcopy
mode. The postcopy-ram capability must be set on both source and des-
tination before the original migration command.
Since
2.5
Example
-> { "execute": "migrate-start-postcopy" }
<- { "return": {} }
MIGRATION (Event)
Emitted when a migration event happens
Arguments
status: MigrationStatus
MigrationStatus describing the current migration status.
Since
2.4
Example
<- {"timestamp": {"seconds": 1432121972, "microseconds": 744001},
"event": "MIGRATION",
"data": {"status": "completed"} }
MIGRATION_PASS (Event)
Emitted from the source side of a migration at the start of each pass
(when it syncs the dirty bitmap)
Arguments
pass: int
An incrementing count (starting at 1 on the first pass)
Since
2.6
Example
{ "timestamp": {"seconds": 1449669631, "microseconds": 239225},
"event": "MIGRATION_PASS", "data": {"pass": 2} }
COLOMessage (Enum)
The message transmission between Primary side and Secondary side.
Values
checkpoint-ready
Secondary VM (SVM) is ready for checkpointing
checkpoint-request
Primary VM (PVM) tells SVM to prepare for checkpointing
checkpoint-reply
SVM gets PVM's checkpoint request
vmstate-send
VM's state will be sent by PVM.
vmstate-size
The total size of VMstate.
vmstate-received
VM's state has been received by SVM.
vmstate-loaded
VM's state has been loaded by SVM.
Since
2.8
COLOMode (Enum)
The COLO current mode.
Values
none COLO is disabled.
primary
COLO node in primary side.
secondary
COLO node in slave side.
Since
2.8
FailoverStatus (Enum)
An enumeration of COLO failover status
Values
none no failover has ever happened
require
got failover requirement but not handled
active in the process of doing failover
completed
finish the process of failover
relaunch
restart the failover process, from 'none' -> 'completed' (Since
2.9)
Since
2.8
COLO_EXIT (Event)
Emitted when VM finishes COLO mode due to some errors happening or at
the request of users.
Arguments
mode: COLOMode
report COLO mode when COLO exited.
reason: COLOExitReason
describes the reason for the COLO exit.
Since
3.1
Example
<- { "timestamp": {"seconds": 2032141960, "microseconds": 417172},
"event": "COLO_EXIT", "data": {"mode": "primary", "reason": "request" } }
COLOExitReason (Enum)
The reason for a COLO exit.
Values
none failover has never happened. This state does not occur in the
COLO_EXIT event, and is only visible in the result of
query-colo-status.
request
COLO exit is due to an external request.
error COLO exit is due to an internal error.
processing
COLO is currently handling a failover (since 4.0).
Since
3.1
x-colo-lost-heartbeat (Command)
Tell qemu that heartbeat is lost, request it to do takeover procedures.
If this command is sent to the PVM, the Primary side will exit COLO
mode. If sent to the Secondary, the Secondary side will run failover
work, then takes over server operation to become the service VM.
Features
unstable
This command is experimental.
Since
2.8
Example
-> { "execute": "x-colo-lost-heartbeat" }
<- { "return": {} }
migrate_cancel (Command)
Cancel the current executing migration process.
Returns
nothing on success
Notes
This command succeeds even if there is no migration process running.
Since
0.14
Example
-> { "execute": "migrate_cancel" }
<- { "return": {} }
migrate-continue (Command)
Continue migration when it's in a paused state.
Arguments
state: MigrationStatus
The state the migration is currently expected to be in
Returns
nothing on success
Since
2.11
Example
-> { "execute": "migrate-continue" , "arguments":
{ "state": "pre-switchover" } }
<- { "return": {} }
migrate (Command)
Migrates the current running guest to another Virtual Machine.
Arguments
uri: string
the Uniform Resource Identifier of the destination VM
blk: boolean (optional)
do block migration (full disk copy)
inc: boolean (optional)
incremental disk copy migration
detach: boolean (optional)
this argument exists only for compatibility reasons and is ig-
nored by QEMU
resume: boolean (optional)
resume one paused migration, default "off". (since 3.0)
Returns
nothing on success
Since
0.14
Notes
1. The 'query-migrate' command should be used to check migration's
progress and final result (this information is provided by the 'sta-
tus' member)
2. All boolean arguments default to false
3. The user Monitor's "detach" argument is invalid in QMP and should
not be used
Example
-> { "execute": "migrate", "arguments": { "uri": "tcp:0:4446" } }
<- { "return": {} }
migrate-incoming (Command)
Start an incoming migration, the qemu must have been started with -in-
coming defer
Arguments
uri: string
The Uniform Resource Identifier identifying the source or ad-
dress to listen on
Returns
nothing on success
Since
2.3
Notes
1. It's a bad idea to use a string for the uri, but it needs to stay
compatible with -incoming and the format of the uri is already ex-
posed above libvirt.
2. QEMU must be started with -incoming defer to allow migrate-incoming
to be used.
3. The uri format is the same as for -incoming
Example
-> { "execute": "migrate-incoming",
"arguments": { "uri": "tcp::4446" } }
<- { "return": {} }
xen-save-devices-state (Command)
Save the state of all devices to file. The RAM and the block devices of
the VM are not saved by this command.
Arguments
filename: string
the file to save the state of the devices to as binary data. See
xen-save-devices-state.txt for a description of the binary for-
mat.
live: boolean (optional)
Optional argument to ask QEMU to treat this command as part of a
live migration. Default to true. (since 2.11)
Returns
Nothing on success
Since
1.1
Example
-> { "execute": "xen-save-devices-state",
"arguments": { "filename": "/tmp/save" } }
<- { "return": {} }
xen-set-global-dirty-log (Command)
Enable or disable the global dirty log mode.
Arguments
enable: boolean
true to enable, false to disable.
Returns
nothing
Since
1.3
Example
-> { "execute": "xen-set-global-dirty-log",
"arguments": { "enable": true } }
<- { "return": {} }
xen-load-devices-state (Command)
Load the state of all devices from file. The RAM and the block devices
of the VM are not loaded by this command.
Arguments
filename: string
the file to load the state of the devices from as binary data.
See xen-save-devices-state.txt for a description of the binary
format.
Since
2.7
Example
-> { "execute": "xen-load-devices-state",
"arguments": { "filename": "/tmp/resume" } }
<- { "return": {} }
xen-set-replication (Command)
Enable or disable replication.
Arguments
enable: boolean
true to enable, false to disable.
primary: boolean
true for primary or false for secondary.
failover: boolean (optional)
true to do failover, false to stop. but cannot be specified if
'enable' is true. default value is false.
Returns
nothing.
Example
-> { "execute": "xen-set-replication",
"arguments": {"enable": true, "primary": false} }
<- { "return": {} }
Since
2.9
If
CONFIG_REPLICATION
ReplicationStatus (Object)
The result format for 'query-xen-replication-status'.
Members
error: boolean
true if an error happened, false if replication is normal.
desc: string (optional)
the human readable error description string, when error is
'true'.
Since
2.9
If
CONFIG_REPLICATION
query-xen-replication-status (Command)
Query replication status while the vm is running.
Returns
A ReplicationStatus object showing the status.
Example
-> { "execute": "query-xen-replication-status" }
<- { "return": { "error": false } }
Since
2.9
If
CONFIG_REPLICATION
xen-colo-do-checkpoint (Command)
Xen uses this command to notify replication to trigger a checkpoint.
Returns
nothing.
Example
-> { "execute": "xen-colo-do-checkpoint" }
<- { "return": {} }
Since
2.9
If
CONFIG_REPLICATION
COLOStatus (Object)
The result format for 'query-colo-status'.
Members
mode: COLOMode
COLO running mode. If COLO is running, this field will return
'primary' or 'secondary'.
last-mode: COLOMode
COLO last running mode. If COLO is running, this field will re-
turn same like mode field, after failover we can use this field
to get last colo mode. (since 4.0)
reason: COLOExitReason
describes the reason for the COLO exit.
Since
3.1
query-colo-status (Command)
Query COLO status while the vm is running.
Returns
A COLOStatus object showing the status.
Example
-> { "execute": "query-colo-status" }
<- { "return": { "mode": "primary", "last-mode": "none", "reason": "request" } }
Since
3.1
migrate-recover (Command)
Provide a recovery migration stream URI.
Arguments
uri: string
the URI to be used for the recovery of migration stream.
Returns
nothing.
Example
-> { "execute": "migrate-recover",
"arguments": { "uri": "tcp:192.168.1.200:12345" } }
<- { "return": {} }
Since
3.0
migrate-pause (Command)
Pause a migration. Currently it only supports postcopy.
Returns
nothing.
Example
-> { "execute": "migrate-pause" }
<- { "return": {} }
Since
3.0
UNPLUG_PRIMARY (Event)
Emitted from source side of a migration when migration state is
WAIT_UNPLUG. Device was unplugged by guest operating system. Device
resources in QEMU are kept on standby to be able to re-plug it in case
of migration failure.
Arguments
device-id: string
QEMU device id of the unplugged device
Since
4.2
Example
<- { "event": "UNPLUG_PRIMARY",
"data": { "device-id": "hostdev0" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
DirtyRateVcpu (Object)
Dirty rate of vcpu.
Members
id: int
vcpu index.
dirty-rate: int
dirty rate.
Since
6.2
DirtyRateStatus (Enum)
An enumeration of dirtyrate status.
Values
unstarted
the dirtyrate thread has not been started.
measuring
the dirtyrate thread is measuring.
measured
the dirtyrate thread has measured and results are available.
Since
5.2
DirtyRateMeasureMode (Enum)
An enumeration of mode of measuring dirtyrate.
Values
page-sampling
calculate dirtyrate by sampling pages.
dirty-ring
calculate dirtyrate by dirty ring.
dirty-bitmap
calculate dirtyrate by dirty bitmap.
Since
6.2
DirtyRateInfo (Object)
Information about current dirty page rate of vm.
Members
dirty-rate: int (optional)
an estimate of the dirty page rate of the VM in units of MB/s,
present only when estimating the rate has completed.
status: DirtyRateStatus
status containing dirtyrate query status includes 'unstarted' or
'measuring' or 'measured'
start-time: int
start time in units of second for calculation
calc-time: int
time in units of second for sample dirty pages
sample-pages: int
page count per GB for sample dirty pages the default value is
512 (since 6.1)
mode: DirtyRateMeasureMode
mode containing method of calculate dirtyrate includes
'page-sampling' and 'dirty-ring' (Since 6.2)
vcpu-dirty-rate: array of DirtyRateVcpu (optional)
dirtyrate for each vcpu if dirty-ring mode specified (Since 6.2)
Since
5.2
calc-dirty-rate (Command)
start calculating dirty page rate for vm
Arguments
calc-time: int
time in units of second for sample dirty pages
sample-pages: int (optional)
page count per GB for sample dirty pages the default value is
512 (since 6.1)
mode: DirtyRateMeasureMode (optional)
mechanism of calculating dirtyrate includes 'page-sampling' and
'dirty-ring' (Since 6.1)
Since
5.2
Example
{"execute": "calc-dirty-rate", "arguments": {"calc-time": 1,
'sample-pages': 512} }
query-dirty-rate (Command)
query dirty page rate in units of MB/s for vm
Since
5.2
DirtyLimitInfo (Object)
Dirty page rate limit information of a virtual CPU.
Members
cpu-index: int
index of a virtual CPU.
limit-rate: int
upper limit of dirty page rate (MB/s) for a virtual CPU, 0 means
unlimited.
current-rate: int
current dirty page rate (MB/s) for a virtual CPU.
Since
7.1
set-vcpu-dirty-limit (Command)
Set the upper limit of dirty page rate for virtual CPUs.
Requires KVM with accelerator property "dirty-ring-size" set. A vir-
tual CPU's dirty page rate is a measure of its memory load. To observe
dirty page rates, use calc-dirty-rate.
Arguments
cpu-index: int (optional)
index of a virtual CPU, default is all.
dirty-rate: int
upper limit of dirty page rate (MB/s) for virtual CPUs.
Since
7.1
Example
{"execute": "set-vcpu-dirty-limit"}
"arguments": { "dirty-rate": 200,
"cpu-index": 1 } }
cancel-vcpu-dirty-limit (Command)
Cancel the upper limit of dirty page rate for virtual CPUs.
Cancel the dirty page limit for the vCPU which has been set with
set-vcpu-dirty-limit command. Note that this command requires support
from dirty ring, same as the "set-vcpu-dirty-limit".
Arguments
cpu-index: int (optional)
index of a virtual CPU, default is all.
Since
7.1
Example
{"execute": "cancel-vcpu-dirty-limit"}
"arguments": { "cpu-index": 1 } }
query-vcpu-dirty-limit (Command)
Returns information about virtual CPU dirty page rate limits, if any.
Since
7.1
Example
{"execute": "query-vcpu-dirty-limit"}
snapshot-save (Command)
Save a VM snapshot
Arguments
job-id: string
identifier for the newly created job
tag: string
name of the snapshot to create
vmstate: string
block device node name to save vmstate to
devices: array of string
list of block device node names to save a snapshot to
Applications should not assume that the snapshot save is complete when
this command returns. The job commands / events must be used to deter-
mine completion and to fetch details of any errors that arise.
Note that execution of the guest CPUs may be stopped during the time it
takes to save the snapshot. A future version of QEMU may ensure CPUs
are executing continuously.
It is strongly recommended that devices contain all writable block de-
vice nodes if a consistent snapshot is required.
If tag already exists, an error will be reported
Returns
nothing
Example
-> { "execute": "snapshot-save",
"arguments": {
"job-id": "snapsave0",
"tag": "my-snap",
"vmstate": "disk0",
"devices": ["disk0", "disk1"]
}
}
<- { "return": { } }
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1432121972, "microseconds": 744001},
"data": {"status": "created", "id": "snapsave0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1432122172, "microseconds": 744001},
"data": {"status": "running", "id": "snapsave0"}}
<- {"event": "STOP",
"timestamp": {"seconds": 1432122372, "microseconds": 744001} }
<- {"event": "RESUME",
"timestamp": {"seconds": 1432122572, "microseconds": 744001} }
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1432122772, "microseconds": 744001},
"data": {"status": "waiting", "id": "snapsave0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1432122972, "microseconds": 744001},
"data": {"status": "pending", "id": "snapsave0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1432123172, "microseconds": 744001},
"data": {"status": "concluded", "id": "snapsave0"}}
-> {"execute": "query-jobs"}
<- {"return": [{"current-progress": 1,
"status": "concluded",
"total-progress": 1,
"type": "snapshot-save",
"id": "snapsave0"}]}
Since
6.0
snapshot-load (Command)
Load a VM snapshot
Arguments
job-id: string
identifier for the newly created job
tag: string
name of the snapshot to load.
vmstate: string
block device node name to load vmstate from
devices: array of string
list of block device node names to load a snapshot from
Applications should not assume that the snapshot load is complete when
this command returns. The job commands / events must be used to deter-
mine completion and to fetch details of any errors that arise.
Note that execution of the guest CPUs will be stopped during the time
it takes to load the snapshot.
It is strongly recommended that devices contain all writable block de-
vice nodes that can have changed since the original snapshot-save com-
mand execution.
Returns
nothing
Example
-> { "execute": "snapshot-load",
"arguments": {
"job-id": "snapload0",
"tag": "my-snap",
"vmstate": "disk0",
"devices": ["disk0", "disk1"]
}
}
<- { "return": { } }
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1472124172, "microseconds": 744001},
"data": {"status": "created", "id": "snapload0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1472125172, "microseconds": 744001},
"data": {"status": "running", "id": "snapload0"}}
<- {"event": "STOP",
"timestamp": {"seconds": 1472125472, "microseconds": 744001} }
<- {"event": "RESUME",
"timestamp": {"seconds": 1472125872, "microseconds": 744001} }
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1472126172, "microseconds": 744001},
"data": {"status": "waiting", "id": "snapload0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1472127172, "microseconds": 744001},
"data": {"status": "pending", "id": "snapload0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1472128172, "microseconds": 744001},
"data": {"status": "concluded", "id": "snapload0"}}
-> {"execute": "query-jobs"}
<- {"return": [{"current-progress": 1,
"status": "concluded",
"total-progress": 1,
"type": "snapshot-load",
"id": "snapload0"}]}
Since
6.0
snapshot-delete (Command)
Delete a VM snapshot
Arguments
job-id: string
identifier for the newly created job
tag: string
name of the snapshot to delete.
devices: array of string
list of block device node names to delete a snapshot from
Applications should not assume that the snapshot delete is complete
when this command returns. The job commands / events must be used to
determine completion and to fetch details of any errors that arise.
Returns
nothing
Example
-> { "execute": "snapshot-delete",
"arguments": {
"job-id": "snapdelete0",
"tag": "my-snap",
"devices": ["disk0", "disk1"]
}
}
<- { "return": { } }
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1442124172, "microseconds": 744001},
"data": {"status": "created", "id": "snapdelete0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1442125172, "microseconds": 744001},
"data": {"status": "running", "id": "snapdelete0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1442126172, "microseconds": 744001},
"data": {"status": "waiting", "id": "snapdelete0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1442127172, "microseconds": 744001},
"data": {"status": "pending", "id": "snapdelete0"}}
<- {"event": "JOB_STATUS_CHANGE",
"timestamp": {"seconds": 1442128172, "microseconds": 744001},
"data": {"status": "concluded", "id": "snapdelete0"}}
-> {"execute": "query-jobs"}
<- {"return": [{"current-progress": 1,
"status": "concluded",
"total-progress": 1,
"type": "snapshot-delete",
"id": "snapdelete0"}]}
Since
6.0
TRANSACTIONS
Abort (Object)
This action can be used to test transaction failure.
Since
1.6
ActionCompletionMode (Enum)
An enumeration of Transactional completion modes.
Values
individual
Do not attempt to cancel any other Actions if any Actions fail
after the Transaction request succeeds. All Actions that can
complete successfully will do so without waiting on others.
This is the default.
grouped
If any Action fails after the Transaction succeeds, cancel all
Actions. Actions do not complete until all Actions are ready to
complete. May be rejected by Actions that do not support this
completion mode.
Since
2.5
TransactionActionKind (Enum)
Values
abort Since 1.6
block-dirty-bitmap-add
Since 2.5
block-dirty-bitmap-remove
Since 4.2
block-dirty-bitmap-clear
Since 2.5
block-dirty-bitmap-enable
Since 4.0
block-dirty-bitmap-disable
Since 4.0
block-dirty-bitmap-merge
Since 4.0
blockdev-backup
Since 2.3
blockdev-snapshot
Since 2.5
blockdev-snapshot-internal-sync
Since 1.7
blockdev-snapshot-sync
since 1.1
drive-backup
Since 1.6
Features
deprecated
Member drive-backup is deprecated. Use member blockdev-backup
instead.
Since
1.1
AbortWrapper (Object)
Members
data: Abort
Not documented
Since
1.6
BlockDirtyBitmapAddWrapper (Object)
Members
data: BlockDirtyBitmapAdd
Not documented
Since
2.5
BlockDirtyBitmapWrapper (Object)
Members
data: BlockDirtyBitmap
Not documented
Since
2.5
BlockDirtyBitmapMergeWrapper (Object)
Members
data: BlockDirtyBitmapMerge
Not documented
Since
4.0
BlockdevBackupWrapper (Object)
Members
data: BlockdevBackup
Not documented
Since
2.3
BlockdevSnapshotWrapper (Object)
Members
data: BlockdevSnapshot
Not documented
Since
2.5
BlockdevSnapshotInternalWrapper (Object)
Members
data: BlockdevSnapshotInternal
Not documented
Since
1.7
BlockdevSnapshotSyncWrapper (Object)
Members
data: BlockdevSnapshotSync
Not documented
Since
1.1
DriveBackupWrapper (Object)
Members
data: DriveBackup
Not documented
Since
1.6
TransactionAction (Object)
A discriminated record of operations that can be performed with trans-
action.
Members
type: TransactionActionKind
Not documented
The members of AbortWrapper when type is "abort"
The members of BlockDirtyBitmapAddWrapper when type is
"block-dirty-bitmap-add"
The members of BlockDirtyBitmapWrapper when type is "block-dirty-bit-
map-remove"
The members of BlockDirtyBitmapWrapper when type is "block-dirty-bit-
map-clear"
The members of BlockDirtyBitmapWrapper when type is "block-dirty-bit-
map-enable"
The members of BlockDirtyBitmapWrapper when type is "block-dirty-bit-
map-disable"
The members of BlockDirtyBitmapMergeWrapper when type is
"block-dirty-bitmap-merge"
The members of BlockdevBackupWrapper when type is "blockdev-backup"
The members of BlockdevSnapshotWrapper when type is "blockdev-snapshot"
The members of BlockdevSnapshotInternalWrapper when type is "block-
dev-snapshot-internal-sync"
The members of BlockdevSnapshotSyncWrapper when type is "blockdev-snap-
shot-sync"
The members of DriveBackupWrapper when type is "drive-backup"
Since
1.1
TransactionProperties (Object)
Optional arguments to modify the behavior of a Transaction.
Members
completion-mode: ActionCompletionMode (optional)
Controls how jobs launched asynchronously by Actions will com-
plete or fail as a group. See ActionCompletionMode for details.
Since
2.5
transaction (Command)
Executes a number of transactionable QMP commands atomically. If any
operation fails, then the entire set of actions will be abandoned and
the appropriate error returned.
For external snapshots, the dictionary contains the device, the file to
use for the new snapshot, and the format. The default format, if not
specified, is qcow2.
Each new snapshot defaults to being created by QEMU (wiping any con-
tents if the file already exists), but it is also possible to reuse an
externally-created file. In the latter case, you should ensure that
the new image file has the same contents as the current one; QEMU can-
not perform any meaningful check. Typically this is achieved by using
the current image file as the backing file for the new image.
On failure, the original disks pre-snapshot attempt will be used.
For internal snapshots, the dictionary contains the device and the
snapshot's name. If an internal snapshot matching name already exists,
the request will be rejected. Only some image formats support it, for
example, qcow2, and rbd,
On failure, qemu will try delete the newly created internal snapshot in
the transaction. When an I/O error occurs during deletion, the user
needs to fix it later with qemu-img or other command.
Arguments
actions: array of TransactionAction
List of TransactionAction; information needed for the respective
operations.
properties: TransactionProperties (optional)
structure of additional options to control the execution of the
transaction. See TransactionProperties for additional detail.
Returns
nothing on success
Errors depend on the operations of the transaction
Note
The transaction aborts on the first failure. Therefore, there will be
information on only one failed operation returned in an error condi-
tion, and subsequent actions will not have been attempted.
Since
1.1
Example
-> { "execute": "transaction",
"arguments": { "actions": [
{ "type": "blockdev-snapshot-sync", "data" : { "device": "ide-hd0",
"snapshot-file": "/some/place/my-image",
"format": "qcow2" } },
{ "type": "blockdev-snapshot-sync", "data" : { "node-name": "myfile",
"snapshot-file": "/some/place/my-image2",
"snapshot-node-name": "node3432",
"mode": "existing",
"format": "qcow2" } },
{ "type": "blockdev-snapshot-sync", "data" : { "device": "ide-hd1",
"snapshot-file": "/some/place/my-image2",
"mode": "existing",
"format": "qcow2" } },
{ "type": "blockdev-snapshot-internal-sync", "data" : {
"device": "ide-hd2",
"name": "snapshot0" } } ] } }
<- { "return": {} }
TRACING
TraceEventState (Enum)
State of a tracing event.
Values
unavailable
The event is statically disabled.
disabled
The event is dynamically disabled.
enabled
The event is dynamically enabled.
Since
2.2
TraceEventInfo (Object)
Information of a tracing event.
Members
name: string
Event name.
state: TraceEventState
Tracing state.
vcpu: boolean
Whether this is a per-vCPU event (since 2.7).
An event is per-vCPU if it has the "vcpu" property in the
"trace-events" files.
Since
2.2
trace-event-get-state (Command)
Query the state of events.
Arguments
name: string
Event name pattern (case-sensitive glob).
vcpu: int (optional)
The vCPU to query (any by default; since 2.7).
Returns
a list of TraceEventInfo for the matching events
An event is returned if:
• its name matches the name pattern, and
• if vcpu is given, the event has the "vcpu" property.
Therefore, if vcpu is given, the operation will only match per-vCPU
events, returning their state on the specified vCPU. Special case: if
name is an exact match, vcpu is given and the event does not have the
"vcpu" property, an error is returned.
Since
2.2
Example
-> { "execute": "trace-event-get-state",
"arguments": { "name": "qemu_memalign" } }
<- { "return": [ { "name": "qemu_memalign", "state": "disabled", "vcpu": false } ] }
trace-event-set-state (Command)
Set the dynamic tracing state of events.
Arguments
name: string
Event name pattern (case-sensitive glob).
enable: boolean
Whether to enable tracing.
ignore-unavailable: boolean (optional)
Do not match unavailable events with name.
vcpu: int (optional)
The vCPU to act upon (all by default; since 2.7).
An event's state is modified if: - its name matches the name pattern,
and - if vcpu is given, the event has the "vcpu" property.
Therefore, if vcpu is given, the operation will only match per-vCPU
events, setting their state on the specified vCPU. Special case: if
name is an exact match, vcpu is given and the event does not have the
"vcpu" property, an error is returned.
Since
2.2
Example
-> { "execute": "trace-event-set-state",
"arguments": { "name": "qemu_memalign", "enable": true } }
<- { "return": {} }
COMPATIBILITY POLICY
CompatPolicyInput (Enum)
Policy for handling "funny" input.
Values
accept Accept silently
reject Reject with an error
crash abort() the process
Since
6.0
CompatPolicyOutput (Enum)
Policy for handling "funny" output.
Values
accept Pass on unchanged
hide Filter out
Since
6.0
CompatPolicy (Object)
Policy for handling deprecated management interfaces.
This is intended for testing users of the management interfaces.
Limitation: covers only syntactic aspects of QMP, i.e. stuff tagged
with feature 'deprecated'. We may want to extend it to cover semantic
aspects and CLI.
Limitation: deprecated-output policy hide is not implemented for enu-
meration values. They behave the same as with policy accept.
Members
deprecated-input: CompatPolicyInput (optional)
how to handle deprecated input (default 'accept')
deprecated-output: CompatPolicyOutput (optional)
how to handle deprecated output (default 'accept')
unstable-input: CompatPolicyInput (optional)
how to handle unstable input (default 'accept') (since 6.2)
unstable-output: CompatPolicyOutput (optional)
how to handle unstable output (default 'accept') (since 6.2)
Since
6.0
QMP MONITOR CONTROL
qmp_capabilities (Command)
Enable QMP capabilities.
Arguments:
Arguments
enable: array of QMPCapability (optional)
An optional list of QMPCapability values to enable. The client
must not enable any capability that is not mentioned in the QMP
greeting message. If the field is not provided, it means no QMP
capabilities will be enabled. (since 2.12)
Example
-> { "execute": "qmp_capabilities",
"arguments": { "enable": [ "oob" ] } }
<- { "return": {} }
Notes
This command is valid exactly when first connecting: it must be issued
before any other command will be accepted, and will fail once the moni-
tor is accepting other commands. (see qemu docs/interop/qmp-spec.txt)
The QMP client needs to explicitly enable QMP capabilities, otherwise
all the QMP capabilities will be turned off by default.
Since
0.13
QMPCapability (Enum)
Enumeration of capabilities to be advertised during initial client con-
nection, used for agreeing on particular QMP extension behaviors.
Values
oob QMP ability to support out-of-band requests. (Please refer to
qmp-spec.txt for more information on OOB)
Since
2.12
VersionTriple (Object)
A three-part version number.
Members
major: int
The major version number.
minor: int
The minor version number.
micro: int
The micro version number.
Since
2.4
VersionInfo (Object)
A description of QEMU's version.
Members
qemu: VersionTriple
The version of QEMU. By current convention, a micro version of
50 signifies a development branch. A micro version greater than
or equal to 90 signifies a release candidate for the next minor
version. A micro version of less than 50 signifies a stable re-
lease.
package: string
QEMU will always set this field to an empty string. Downstream
versions of QEMU should set this to a non-empty string. The ex-
act format depends on the downstream however it highly recom-
mended that a unique name is used.
Since
0.14
query-version (Command)
Returns the current version of QEMU.
Returns
A VersionInfo object describing the current version of QEMU.
Since
0.14
Example
-> { "execute": "query-version" }
<- {
"return":{
"qemu":{
"major":0,
"minor":11,
"micro":5
},
"package":""
}
}
CommandInfo (Object)
Information about a QMP command
Members
name: string
The command name
Since
0.14
query-commands (Command)
Return a list of supported QMP commands by this server
Returns
A list of CommandInfo for all supported commands
Since
0.14
Example
-> { "execute": "query-commands" }
<- {
"return":[
{
"name":"query-balloon"
},
{
"name":"system_powerdown"
}
]
}
Note
This example has been shortened as the real response is too long.
quit (Command)
This command will cause the QEMU process to exit gracefully. While ev-
ery attempt is made to send the QMP response before terminating, this
is not guaranteed. When using this interface, a premature EOF would
not be unexpected.
Since
0.14
Example
-> { "execute": "quit" }
<- { "return": {} }
MonitorMode (Enum)
An enumeration of monitor modes.
Values
readline
HMP monitor (human-oriented command line interface)
control
QMP monitor (JSON-based machine interface)
Since
5.0
MonitorOptions (Object)
Options to be used for adding a new monitor.
Members
id: string (optional)
Name of the monitor
mode: MonitorMode (optional)
Selects the monitor mode (default: readline in the system
emulator, control in qemu-storage-daemon)
pretty: boolean (optional)
Enables pretty printing (QMP only)
chardev: string
Name of a character device to expose the monitor on
Since
5.0
QMP INTROSPECTION
query-qmp-schema (Command)
Command query-qmp-schema exposes the QMP wire ABI as an array of
SchemaInfo. This lets QMP clients figure out what commands and events
are available in this QEMU, and their parameters and results.
However, the SchemaInfo can't reflect all the rules and restrictions
that apply to QMP. It's interface introspection (figuring out what's
there), not interface specification. The specification is in the QAPI
schema.
Furthermore, while we strive to keep the QMP wire format backwards-com-
patible across qemu versions, the introspection output is not guaran-
teed to have the same stability. For example, one version of qemu may
list an object member as an optional non-variant, while another lists
the same member only through the object's variants; or the type of a
member may change from a generic string into a specific enum or from
one specific type into an alternate that includes the original type
alongside something else.
Returns
array of SchemaInfo, where each element describes an entity in the ABI:
command, event, type, ...
The order of the various SchemaInfo is unspecified; however, all names
are guaranteed to be unique (no name will be duplicated with different
meta-types).
Note
the QAPI schema is also used to help define internal interfaces, by
defining QAPI types. These are not part of the QMP wire ABI, and
therefore not returned by this command.
Since
2.5
SchemaMetaType (Enum)
This is a SchemaInfo's meta type, i.e. the kind of entity it describes.
Values
builtin
a predefined type such as 'int' or 'bool'.
enum an enumeration type
array an array type
object an object type (struct or union)
alternate
an alternate type
command
a QMP command
event a QMP event
Since
2.5
SchemaInfo (Object)
Members
name: string
the entity's name, inherited from base. The SchemaInfo is al-
ways referenced by this name. Commands and events have the name
defined in the QAPI schema. Unlike command and event names,
type names are not part of the wire ABI. Consequently, type
names are meaningless strings here, although they are still
guaranteed unique regardless of meta-type.
meta-type: SchemaMetaType
the entity's meta type, inherited from base.
features: array of string (optional)
names of features associated with the entity, in no particular
order. (since 4.1 for object types, 4.2 for commands, 5.0 for
the rest)
The members of SchemaInfoBuiltin when meta-type is "builtin"
The members of SchemaInfoEnum when meta-type is "enum"
The members of SchemaInfoArray when meta-type is "array"
The members of SchemaInfoObject when meta-type is "object"
The members of SchemaInfoAlternate when meta-type is "alternate"
The members of SchemaInfoCommand when meta-type is "command"
The members of SchemaInfoEvent when meta-type is "event"
Additional members depend on the value of meta-type.
Since
2.5
SchemaInfoBuiltin (Object)
Additional SchemaInfo members for meta-type 'builtin'.
Members
json-type: JSONType
the JSON type used for this type on the wire.
Since
2.5
JSONType (Enum)
The four primitive and two structured types according to RFC 8259 sec-
tion 1, plus 'int' (split off 'number'), plus the obvious top type
'value'.
Values
string Not documented
number Not documented
int Not documented
boolean
Not documented
null Not documented
object Not documented
array Not documented
value Not documented
Since
2.5
SchemaInfoEnum (Object)
Additional SchemaInfo members for meta-type 'enum'.
Members
members: array of SchemaInfoEnumMember
the enum type's members, in no particular order (since 6.2).
values: array of string
the enumeration type's member names, in no particular order.
Redundant with members. Just for backward compatibility.
Features
deprecated
Member values is deprecated. Use members instead.
Values of this type are JSON string on the wire.
Since
2.5
SchemaInfoEnumMember (Object)
An object member.
Members
name: string
the member's name, as defined in the QAPI schema.
features: array of string (optional)
names of features associated with the member, in no particular
order.
Since
6.2
SchemaInfoArray (Object)
Additional SchemaInfo members for meta-type 'array'.
Members
element-type: string
the array type's element type.
Values of this type are JSON array on the wire.
Since
2.5
SchemaInfoObject (Object)
Additional SchemaInfo members for meta-type 'object'.
Members
members: array of SchemaInfoObjectMember
the object type's (non-variant) members, in no particular order.
tag: string (optional)
the name of the member serving as type tag. An element of mem-
bers with this name must exist.
variants: array of SchemaInfoObjectVariant (optional)
variant members, i.e. additional members that depend on the type
tag's value. Present exactly when tag is present. The variants
are in no particular order, and may even differ from the order
of the values of the enum type of the tag.
Values of this type are JSON object on the wire.
Since
2.5
SchemaInfoObjectMember (Object)
An object member.
Members
name: string
the member's name, as defined in the QAPI schema.
type: string
the name of the member's type.
default: value (optional)
default when used as command parameter. If absent, the parame-
ter is mandatory. If present, the value must be null. The pa-
rameter is optional, and behavior when it's missing is not spec-
ified here. Future extension: if present and non-null, the pa-
rameter is optional, and defaults to this value.
features: array of string (optional)
names of features associated with the member, in no particular
order. (since 5.0)
Since
2.5
SchemaInfoObjectVariant (Object)
The variant members for a value of the type tag.
Members
case: string
a value of the type tag.
type: string
the name of the object type that provides the variant members
when the type tag has value case.
Since
2.5
SchemaInfoAlternate (Object)
Additional SchemaInfo members for meta-type 'alternate'.
Members
members: array of SchemaInfoAlternateMember
the alternate type's members, in no particular order. The mem-
bers' wire encoding is distinct, see docs/de-
vel/qapi-code-gen.txt section Alternate types.
On the wire, this can be any of the members.
Since
2.5
SchemaInfoAlternateMember (Object)
An alternate member.
Members
type: string
the name of the member's type.
Since
2.5
SchemaInfoCommand (Object)
Additional SchemaInfo members for meta-type 'command'.
Members
arg-type: string
the name of the object type that provides the command's parame-
ters.
ret-type: string
the name of the command's result type.
allow-oob: boolean (optional)
whether the command allows out-of-band execution, defaults to
false (Since: 2.12)
TODO
success-response (currently irrelevant, because it's QGA, not QMP)
Since
2.5
SchemaInfoEvent (Object)
Additional SchemaInfo members for meta-type 'event'.
Members
arg-type: string
the name of the object type that provides the event's parame-
ters.
Since
2.5
QEMU OBJECT MODEL (QOM)
ObjectPropertyInfo (Object)
Members
name: string
the name of the property
type: string
the type of the property. This will typically come in one of
four forms:
1. A primitive type such as 'u8', 'u16', 'bool', 'str', or 'dou-
ble'. These types are mapped to the appropriate JSON type.
2. A child type in the form 'child<subtype>' where subtype is a
qdev device type name. Child properties create the composi-
tion tree.
3. A link type in the form 'link<subtype>' where subtype is a
qdev device type name. Link properties form the device model
graph.
description: string (optional)
if specified, the description of the property.
default-value: value (optional)
the default value, if any (since 5.0)
Since
1.2
qom-list (Command)
This command will list any properties of a object given a path in the
object model.
Arguments
path: string
the path within the object model. See qom-get for a description
of this parameter.
Returns
a list of ObjectPropertyInfo that describe the properties of the ob-
ject.
Since
1.2
Example
-> { "execute": "qom-list",
"arguments": { "path": "/chardevs" } }
<- { "return": [ { "name": "type", "type": "string" },
{ "name": "parallel0", "type": "child<chardev-vc>" },
{ "name": "serial0", "type": "child<chardev-vc>" },
{ "name": "mon0", "type": "child<chardev-stdio>" } ] }
qom-get (Command)
This command will get a property from a object model path and return
the value.
Arguments
path: string
The path within the object model. There are two forms of sup-
ported paths--absolute and partial paths.
Absolute paths are derived from the root object and can follow
child<> or link<> properties. Since they can follow link<>
properties, they can be arbitrarily long. Absolute paths look
like absolute filenames and are prefixed with a leading slash.
Partial paths look like relative filenames. They do not begin
with a prefix. The matching rules for partial paths are subtle
but designed to make specifying objects easy. At each level of
the composition tree, the partial path is matched as an absolute
path. The first match is not returned. At least two matches
are searched for. A successful result is only returned if only
one match is found. If more than one match is found, a flag is
return to indicate that the match was ambiguous.
property: string
The property name to read
Returns
The property value. The type depends on the property type. child<> and
link<> properties are returned as #str pathnames. All integer property
types (u8, u16, etc) are returned as #int.
Since
1.2
Example
1. Use absolute path
-> { "execute": "qom-get",
"arguments": { "path": "/machine/unattached/device[0]",
"property": "hotplugged" } }
<- { "return": false }
2. Use partial path
-> { "execute": "qom-get",
"arguments": { "path": "unattached/sysbus",
"property": "type" } }
<- { "return": "System" }
qom-set (Command)
This command will set a property from a object model path.
Arguments
path: string
see qom-get for a description of this parameter
property: string
the property name to set
value: value
a value who's type is appropriate for the property type. See
qom-get for a description of type mapping.
Since
1.2
Example
-> { "execute": "qom-set",
"arguments": { "path": "/machine",
"property": "graphics",
"value": false } }
<- { "return": {} }
ObjectTypeInfo (Object)
This structure describes a search result from qom-list-types
Members
name: string
the type name found in the search
abstract: boolean (optional)
the type is abstract and can't be directly instantiated. Omit-
ted if false. (since 2.10)
parent: string (optional)
Name of parent type, if any (since 2.10)
Since
1.1
qom-list-types (Command)
This command will return a list of types given search parameters
Arguments
implements: string (optional)
if specified, only return types that implement this type name
abstract: boolean (optional)
if true, include abstract types in the results
Returns
a list of ObjectTypeInfo or an empty list if no results are found
Since
1.1
qom-list-properties (Command)
List properties associated with a QOM object.
Arguments
typename: string
the type name of an object
Note
objects can create properties at runtime, for example to describe links
between different devices and/or objects. These properties are not in-
cluded in the output of this command.
Returns
a list of ObjectPropertyInfo describing object properties
Since
2.12
CanHostSocketcanProperties (Object)
Properties for can-host-socketcan objects.
Members
if: string
interface name of the host system CAN bus to connect to
canbus: string
object ID of the can-bus object to connect to the host interface
Since
2.12
ColoCompareProperties (Object)
Properties for colo-compare objects.
Members
primary_in: string
name of the character device backend to use for the primary in-
put (incoming packets are redirected to outdev)
secondary_in: string
name of the character device backend to use for secondary input
(incoming packets are only compared to the input on primary_in
and then dropped)
outdev: string
name of the character device backend to use for output
iothread: string
name of the iothread to run in
notify_dev: string (optional)
name of the character device backend to be used to communicate
with the remote colo-frame (only for Xen COLO)
compare_timeout: int (optional)
the maximum time to hold a packet from primary_in for comparison
with an incoming packet on secondary_in in milliseconds (de-
fault: 3000)
expired_scan_cycle: int (optional)
the interval at which colo-compare checks whether packets from
primary have timed out, in milliseconds (default: 3000)
max_queue_size: int (optional)
the maximum number of packets to keep in the queue for comparing
with incoming packets from secondary_in. If the queue is full
and additional packets are received, the additional packets are
dropped. (default: 1024)
vnet_hdr_support: boolean (optional)
if true, vnet header support is enabled (default: false)
Since
2.8
CryptodevBackendProperties (Object)
Properties for cryptodev-backend and cryptodev-backend-builtin objects.
Members
queues: int (optional)
the number of queues for the cryptodev backend. Ignored for
cryptodev-backend and must be 1 for cryptodev-backend-builtin.
(default: 1)
Since
2.8
CryptodevVhostUserProperties (Object)
Properties for cryptodev-vhost-user objects.
Members
chardev: string
the name of a Unix domain socket character device that connects
to the vhost-user server
The members of CryptodevBackendProperties
Since
2.12
DBusVMStateProperties (Object)
Properties for dbus-vmstate objects.
Members
addr: string
the name of the DBus bus to connect to
id-list: string (optional)
a comma separated list of DBus IDs of helpers whose data should
be included in the VM state on migration
Since
5.0
NetfilterInsert (Enum)
Indicates where to insert a netfilter relative to a given other filter.
Values
before insert before the specified filter
behind insert behind the specified filter
Since
5.0
NetfilterProperties (Object)
Properties for objects of classes derived from netfilter.
Members
netdev: string
id of the network device backend to filter
queue: NetFilterDirection (optional)
indicates which queue(s) to filter (default: all)
status: string (optional)
indicates whether the filter is enabled ("on") or disabled
("off") (default: "on")
position: string (optional)
specifies where the filter should be inserted in the filter
list. "head" means the filter is inserted at the head of the
filter list, before any existing filters. "tail" means the fil-
ter is inserted at the tail of the filter list, behind any ex-
isting filters (default). "id=<id>" means the filter is in-
serted before or behind the filter specified by <id>, depending
on the insert property. (default: "tail")
insert: NetfilterInsert (optional)
where to insert the filter relative to the filter given in posi-
tion. Ignored if position is "head" or "tail". (default: be-
hind)
Since
2.5
FilterBufferProperties (Object)
Properties for filter-buffer objects.
Members
interval: int
a non-zero interval in microseconds. All packets arriving in
the given interval are delayed until the end of the interval.
The members of NetfilterProperties
Since
2.5
FilterDumpProperties (Object)
Properties for filter-dump objects.
Members
file: string
the filename where the dumped packets should be stored
maxlen: int (optional)
maximum number of bytes in a packet that are stored (default:
65536)
The members of NetfilterProperties
Since
2.5
FilterMirrorProperties (Object)
Properties for filter-mirror objects.
Members
outdev: string
the name of a character device backend to which all incoming
packets are mirrored
vnet_hdr_support: boolean (optional)
if true, vnet header support is enabled (default: false)
The members of NetfilterProperties
Since
2.6
FilterRedirectorProperties (Object)
Properties for filter-redirector objects.
At least one of indev or outdev must be present. If both are present,
they must not refer to the same character device backend.
Members
indev: string (optional)
the name of a character device backend from which packets are
received and redirected to the filtered network device
outdev: string (optional)
the name of a character device backend to which all incoming
packets are redirected
vnet_hdr_support: boolean (optional)
if true, vnet header support is enabled (default: false)
The members of NetfilterProperties
Since
2.6
FilterRewriterProperties (Object)
Properties for filter-rewriter objects.
Members
vnet_hdr_support: boolean (optional)
if true, vnet header support is enabled (default: false)
The members of NetfilterProperties
Since
2.8
InputBarrierProperties (Object)
Properties for input-barrier objects.
Members
name: string
the screen name as declared in the screens section of bar-
rier.conf
server: string (optional)
hostname of the Barrier server (default: "localhost")
port: string (optional)
TCP port of the Barrier server (default: "24800")
x-origin: string (optional)
x coordinate of the leftmost pixel on the guest screen (default:
"0")
y-origin: string (optional)
y coordinate of the topmost pixel on the guest screen (default:
"0")
width: string (optional)
the width of secondary screen in pixels (default: "1920")
height: string (optional)
the height of secondary screen in pixels (default: "1080")
Since
4.2
InputLinuxProperties (Object)
Properties for input-linux objects.
Members
evdev: string
the path of the host evdev device to use
grab_all: boolean (optional)
if true, grab is toggled for all devices (e.g. both keyboard and
mouse) instead of just one device (default: false)
repeat: boolean (optional)
enables auto-repeat events (default: false)
grab-toggle: GrabToggleKeys (optional)
the key or key combination that toggles device grab (default:
ctrl-ctrl)
Since
2.6
EventLoopBaseProperties (Object)
Common properties for event loops
Members
aio-max-batch: int (optional)
maximum number of requests in a batch for the AIO engine, 0
means that the engine will use its default. (default: 0)
thread-pool-min: int (optional)
minimum number of threads reserved in the thread pool (de-
fault:0)
thread-pool-max: int (optional)
maximum number of threads the thread pool can contain (de-
fault:64)
Since
7.1
IothreadProperties (Object)
Properties for iothread objects.
Members
poll-max-ns: int (optional)
the maximum number of nanoseconds to busy wait for events. 0
means polling is disabled (default: 32768 on POSIX hosts, 0 oth-
erwise)
poll-grow: int (optional)
the multiplier used to increase the polling time when the algo-
rithm detects it is missing events due to not polling long
enough. 0 selects a default behaviour (default: 0)
poll-shrink: int (optional)
the divisor used to decrease the polling time when the algorithm
detects it is spending too long polling without encountering
events. 0 selects a default behaviour (default: 0)
The members of EventLoopBaseProperties
The aio-max-batch option is available since 6.1.
Since
2.0
MainLoopProperties (Object)
Properties for the main-loop object.
Members
The members of EventLoopBaseProperties
Since
7.1
MemoryBackendProperties (Object)
Properties for objects of classes derived from memory-backend.
Members
merge: boolean (optional)
if true, mark the memory as mergeable (default depends on the
machine type)
dump: boolean (optional)
if true, include the memory in core dumps (default depends on
the machine type)
host-nodes: array of int (optional)
the list of NUMA host nodes to bind the memory to
policy: HostMemPolicy (optional)
the NUMA policy (default: 'default')
prealloc: boolean (optional)
if true, preallocate memory (default: false)
prealloc-threads: int (optional)
number of CPU threads to use for prealloc (default: 1)
prealloc-context: string (optional)
thread context to use for creation of preallocation threads (de-
fault: none) (since 7.2)
share: boolean (optional)
if false, the memory is private to QEMU; if true, it is shared
(default: false)
reserve: boolean (optional)
if true, reserve swap space (or huge pages) if applicable (de-
fault: true) (since 6.1)
size: int
size of the memory region in bytes
x-use-canonical-path-for-ramblock-id: boolean (optional)
if true, the canonical path is used for ramblock-id. Disable
this for 4.0 machine types or older to allow migration with
newer QEMU versions. (default: false generally, but true for
machine types <= 4.0)
Note
prealloc=true and reserve=false cannot be set at the same time. With
reserve=true, the behavior depends on the operating system: for exam-
ple, Linux will not reserve swap space for shared file mappings -- "not
applicable". In contrast, reserve=false will bail out if it cannot be
configured accordingly.
Since
2.1
MemoryBackendFileProperties (Object)
Properties for memory-backend-file objects.
Members
align: int (optional)
the base address alignment when QEMU mmap(2)s mem-path. Some
backend stores specified by mem-path require an alignment dif-
ferent than the default one used by QEMU, e.g. the device DAX
/dev/dax0.0 requires 2M alignment rather than 4K. In such cases,
users can specify the required alignment via this option. 0 se-
lects a default alignment (currently the page size). (default:
0)
discard-data: boolean (optional)
if true, the file contents can be destroyed when QEMU exits, to
avoid unnecessarily flushing data to the backing file. Note that
discard-data is only an optimization, and QEMU might not discard
file contents if it aborts unexpectedly or is terminated using
SIGKILL. (default: false)
mem-path: string
the path to either a shared memory or huge page filesystem mount
pmem: boolean (optional) (If: CONFIG_LIBPMEM)
specifies whether the backing file specified by mem-path is in
host persistent memory that can be accessed using the SNIA NVM
programming model (e.g. Intel NVDIMM).
readonly: boolean (optional)
if true, the backing file is opened read-only; if false, it is
opened read-write. (default: false)
The members of MemoryBackendProperties
Since
2.1
MemoryBackendMemfdProperties (Object)
Properties for memory-backend-memfd objects.
The share boolean option is true by default with memfd.
Members
hugetlb: boolean (optional)
if true, the file to be created resides in the hugetlbfs
filesystem (default: false)
hugetlbsize: int (optional)
the hugetlb page size on systems that support multiple hugetlb
page sizes (it must be a power of 2 value supported by the sys-
tem). 0 selects a default page size. This option is ignored if
hugetlb is false. (default: 0)
seal: boolean (optional)
if true, create a sealed-file, which will block further resizing
of the memory (default: true)
The members of MemoryBackendProperties
Since
2.12
MemoryBackendEpcProperties (Object)
Properties for memory-backend-epc objects.
The share boolean option is true by default with epc
The merge boolean option is false by default with epc
The dump boolean option is false by default with epc
Members
The members of MemoryBackendProperties
Since
6.2
PrManagerHelperProperties (Object)
Properties for pr-manager-helper objects.
Members
path: string
the path to a Unix domain socket for connecting to the external
helper
Since
2.11
QtestProperties (Object)
Properties for qtest objects.
Members
chardev: string
the chardev to be used to receive qtest commands on.
log: string (optional)
the path to a log file
Since
6.0
RemoteObjectProperties (Object)
Properties for x-remote-object objects.
Members
fd: string
file descriptor name previously passed via 'getfd' command
devid: string
the id of the device to be associated with the file descriptor
Since
6.0
VfioUserServerProperties (Object)
Properties for x-vfio-user-server objects.
Members
socket: SocketAddress
socket to be used by the libvfio-user library
device: string
the ID of the device to be emulated at the server
Since
7.1
RngProperties (Object)
Properties for objects of classes derived from rng.
Members
opened: boolean (optional)
if true, the device is opened immediately when applying this op-
tion and will probably fail when processing the next option.
Don't use; only provided for compatibility. (default: false)
Features
deprecated
Member opened is deprecated. Setting true doesn't make sense,
and false is already the default.
Since
1.3
RngEgdProperties (Object)
Properties for rng-egd objects.
Members
chardev: string
the name of a character device backend that provides the connec-
tion to the RNG daemon
The members of RngProperties
Since
1.3
RngRandomProperties (Object)
Properties for rng-random objects.
Members
filename: string (optional)
the filename of the device on the host to obtain entropy from
(default: "/dev/urandom")
The members of RngProperties
Since
1.3
SevGuestProperties (Object)
Properties for sev-guest objects.
Members
sev-device: string (optional)
SEV device to use (default: "/dev/sev")
dh-cert-file: string (optional)
guest owners DH certificate (encoded with base64)
session-file: string (optional)
guest owners session parameters (encoded with base64)
policy: int (optional)
SEV policy value (default: 0x1)
handle: int (optional)
SEV firmware handle (default: 0)
cbitpos: int (optional)
C-bit location in page table entry (default: 0)
reduced-phys-bits: int
number of bits in physical addresses that become unavailable
when SEV is enabled
kernel-hashes: boolean (optional)
if true, add hashes of kernel/initrd/cmdline to a designated
guest firmware page for measured boot with -kernel (default:
false) (since 6.2)
Since
2.12
ThreadContextProperties (Object)
Properties for thread context objects.
Members
cpu-affinity: array of int (optional)
the list of host CPU numbers used as CPU affinity for all
threads created in the thread context (default: QEMU main thread
CPU affinity)
node-affinity: array of int (optional)
the list of host node numbers that will be resolved to a list of
host CPU numbers used as CPU affinity. This is a shortcut for
specifying the list of host CPU numbers belonging to the host
nodes manually by setting cpu-affinity. (default: QEMU main
thread affinity)
Since
7.2
ObjectType (Enum)
Values
authz-list
Not documented
authz-listfile
Not documented
authz-pam
Not documented
authz-simple
Not documented
can-bus
Not documented
can-host-socketcan (If: CONFIG_LINUX)
Not documented
colo-compare
Not documented
cryptodev-backend
Not documented
cryptodev-backend-builtin
Not documented
cryptodev-backend-lkcf
Not documented
cryptodev-vhost-user (If: CONFIG_VHOST_CRYPTO)
Not documented
dbus-vmstate
Not documented
filter-buffer
Not documented
filter-dump
Not documented
filter-mirror
Not documented
filter-redirector
Not documented
filter-replay
Not documented
filter-rewriter
Not documented
input-barrier
Not documented
input-linux (If: CONFIG_LINUX)
Not documented
iothread
Not documented
main-loop
Not documented
memory-backend-epc (If: CONFIG_LINUX)
Not documented
memory-backend-file
Not documented
memory-backend-memfd (If: CONFIG_LINUX)
Not documented
memory-backend-ram
Not documented
pef-guest
Not documented
pr-manager-helper (If: CONFIG_LINUX)
Not documented
qtest Not documented
rng-builtin
Not documented
rng-egd
Not documented
rng-random (If: CONFIG_POSIX)
Not documented
secret Not documented
secret_keyring (If: CONFIG_SECRET_KEYRING)
Not documented
sev-guest
Not documented
thread-context
Not documented
s390-pv-guest
Not documented
throttle-group
Not documented
tls-creds-anon
Not documented
tls-creds-psk
Not documented
tls-creds-x509
Not documented
tls-cipher-suites
Not documented
x-remote-object
Not documented
x-vfio-user-server
Not documented
Features
unstable
Member x-remote-object is experimental.
Since
6.0
ObjectOptions (Object)
Describes the options of a user creatable QOM object.
Members
qom-type: ObjectType
the class name for the object to be created
id: string
the name of the new object
The members of AuthZListProperties when qom-type is "authz-list"
The members of AuthZListFileProperties when qom-type is "authz-list-
file"
The members of AuthZPAMProperties when qom-type is "authz-pam"
The members of AuthZSimpleProperties when qom-type is "authz-simple"
The members of CanHostSocketcanProperties when qom-type is
"can-host-socketcan" (If: CONFIG_LINUX)
The members of ColoCompareProperties when qom-type is "colo-compare"
The members of CryptodevBackendProperties when qom-type is "cryp-
todev-backend"
The members of CryptodevBackendProperties when qom-type is "cryp-
todev-backend-builtin"
The members of CryptodevBackendProperties when qom-type is "cryp-
todev-backend-lkcf"
The members of CryptodevVhostUserProperties when qom-type is "cryp-
todev-vhost-user" (If: CONFIG_VHOST_CRYPTO)
The members of DBusVMStateProperties when qom-type is "dbus-vmstate"
The members of FilterBufferProperties when qom-type is "filter-buffer"
The members of FilterDumpProperties when qom-type is "filter-dump"
The members of FilterMirrorProperties when qom-type is "filter-mirror"
The members of FilterRedirectorProperties when qom-type is "fil-
ter-redirector"
The members of NetfilterProperties when qom-type is "filter-replay"
The members of FilterRewriterProperties when qom-type is "fil-
ter-rewriter"
The members of InputBarrierProperties when qom-type is "input-barrier"
The members of InputLinuxProperties when qom-type is "input-linux" (If:
CONFIG_LINUX)
The members of IothreadProperties when qom-type is "iothread"
The members of MainLoopProperties when qom-type is "main-loop"
The members of MemoryBackendEpcProperties when qom-type is "mem-
ory-backend-epc" (If: CONFIG_LINUX)
The members of MemoryBackendFileProperties when qom-type is "mem-
ory-backend-file"
The members of MemoryBackendMemfdProperties when qom-type is "mem-
ory-backend-memfd" (If: CONFIG_LINUX)
The members of MemoryBackendProperties when qom-type is "memory-back-
end-ram"
The members of PrManagerHelperProperties when qom-type is "pr-man-
ager-helper" (If: CONFIG_LINUX)
The members of QtestProperties when qom-type is "qtest"
The members of RngProperties when qom-type is "rng-builtin"
The members of RngEgdProperties when qom-type is "rng-egd"
The members of RngRandomProperties when qom-type is "rng-random" (If:
CONFIG_POSIX)
The members of SecretProperties when qom-type is "secret"
The members of SecretKeyringProperties when qom-type is "se-
cret_keyring" (If: CONFIG_SECRET_KEYRING)
The members of SevGuestProperties when qom-type is "sev-guest"
The members of ThreadContextProperties when qom-type is "thread-con-
text"
The members of ThrottleGroupProperties when qom-type is "throt-
tle-group"
The members of TlsCredsAnonProperties when qom-type is "tls-creds-anon"
The members of TlsCredsPskProperties when qom-type is "tls-creds-psk"
The members of TlsCredsX509Properties when qom-type is "tls-creds-x509"
The members of TlsCredsProperties when qom-type is "tls-cipher-suites"
The members of RemoteObjectProperties when qom-type is "x-remote-ob-
ject"
The members of VfioUserServerProperties when qom-type is
"x-vfio-user-server"
Since
6.0
object-add (Command)
Create a QOM object.
Arguments
The members of ObjectOptions
Returns
Nothing on success Error if qom-type is not a valid class name
Since
2.0
Example
-> { "execute": "object-add",
"arguments": { "qom-type": "rng-random", "id": "rng1",
"filename": "/dev/hwrng" } }
<- { "return": {} }
object-del (Command)
Remove a QOM object.
Arguments
id: string
the name of the QOM object to remove
Returns
Nothing on success Error if id is not a valid id for a QOM object
Since
2.0
Example
-> { "execute": "object-del", "arguments": { "id": "rng1" } }
<- { "return": {} }
DEVICE INFRASTRUCTURE (QDEV)
device-list-properties (Command)
List properties associated with a device.
Arguments
typename: string
the type name of a device
Returns
a list of ObjectPropertyInfo describing a devices properties
Note
objects can create properties at runtime, for example to describe links
between different devices and/or objects. These properties are not in-
cluded in the output of this command.
Since
1.2
device_add (Command)
Add a device.
Arguments
driver: string
the name of the new device's driver
bus: string (optional)
the device's parent bus (device tree path)
id: string (optional)
the device's ID, must be unique
Features
json-cli
If present, the "-device" command line option supports JSON syn-
tax with a structure identical to the arguments of this command.
json-cli-hotplug
If present, the "-device" command line option supports JSON syn-
tax without the reference counting leak that broke hot-unplug
Notes
Additional arguments depend on the type.
1. For detailed information about this command, please refer to the
'docs/qdev-device-use.txt' file.
2. It's possible to list device properties by running QEMU with the
"-device DEVICE,help" command-line argument, where DEVICE is the de-
vice's name
Example
-> { "execute": "device_add",
"arguments": { "driver": "e1000", "id": "net1",
"bus": "pci.0",
"mac": "52:54:00:12:34:56" } }
<- { "return": {} }
TODO
This command effectively bypasses QAPI completely due to its "addi-
tional arguments" business. It shouldn't have been added to the schema
in this form. It should be qapified properly, or replaced by a prop-
erly qapified command.
Since
0.13
device_del (Command)
Remove a device from a guest
Arguments
id: string
the device's ID or QOM path
Returns
Nothing on success If id is not a valid device, DeviceNotFound
Notes
When this command completes, the device may not be removed from the
guest. Hot removal is an operation that requires guest cooperation.
This command merely requests that the guest begin the hot removal
process. Completion of the device removal process is signaled with a
DEVICE_DELETED event. Guest reset will automatically complete removal
for all devices. If a guest-side error in the hot removal process is
detected, the device will not be removed and a DEVICE_UNPLUG_GUEST_ER-
ROR event is sent. Some errors cannot be detected.
Since
0.14
Example
-> { "execute": "device_del",
"arguments": { "id": "net1" } }
<- { "return": {} }
-> { "execute": "device_del",
"arguments": { "id": "/machine/peripheral-anon/device[0]" } }
<- { "return": {} }
DEVICE_DELETED (Event)
Emitted whenever the device removal completion is acknowledged by the
guest. At this point, it's safe to reuse the specified device ID. De-
vice removal can be initiated by the guest or by HMP/QMP commands.
Arguments
device: string (optional)
the device's ID if it has one
path: string
the device's QOM path
Since
1.5
Example
<- { "event": "DEVICE_DELETED",
"data": { "device": "virtio-net-pci-0",
"path": "/machine/peripheral/virtio-net-pci-0" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
DEVICE_UNPLUG_GUEST_ERROR (Event)
Emitted when a device hot unplug fails due to a guest reported error.
Arguments
device: string (optional)
the device's ID if it has one
path: string
the device's QOM path
Since
6.2
Example
<- { "event": "DEVICE_UNPLUG_GUEST_ERROR",
"data": { "device": "core1",
"path": "/machine/peripheral/core1" },
"timestamp": { "seconds": 1615570772, "microseconds": 202844 } }
MACHINES
SysEmuTarget (Enum)
The comprehensive enumeration of QEMU system emulation ("softmmu") tar-
gets. Run "./configure --help" in the project root directory, and look
for the *-softmmu targets near the "--target-list" option. The individ-
ual target constants are not documented here, for the time being.
Values
rx since 5.0
avr since 5.1
aarch64
Not documented
alpha Not documented
arm Not documented
cris Not documented
hppa Not documented
i386 Not documented
loongarch64
Not documented
m68k Not documented
microblaze
Not documented
microblazeel
Not documented
mips Not documented
mips64 Not documented
mips64el
Not documented
mipsel Not documented
nios2 Not documented
or1k Not documented
ppc Not documented
ppc64 Not documented
riscv32
Not documented
riscv64
Not documented
s390x Not documented
sh4 Not documented
sh4eb Not documented
sparc Not documented
sparc64
Not documented
tricore
Not documented
x86_64 Not documented
xtensa Not documented
xtensaeb
Not documented
Notes
The resulting QMP strings can be appended to the "qemu-system-" prefix
to produce the corresponding QEMU executable name. This is true even
for "qemu-system-x86_64".
Since
3.0
CpuS390State (Enum)
An enumeration of cpu states that can be assumed by a virtual S390 CPU
Values
uninitialized
Not documented
stopped
Not documented
check-stop
Not documented
operating
Not documented
load Not documented
Since
2.12
CpuInfoS390 (Object)
Additional information about a virtual S390 CPU
Members
cpu-state: CpuS390State
the virtual CPU's state
Since
2.12
CpuInfoFast (Object)
Information about a virtual CPU
Members
cpu-index: int
index of the virtual CPU
qom-path: string
path to the CPU object in the QOM tree
thread-id: int
ID of the underlying host thread
props: CpuInstanceProperties (optional)
properties describing to which node/socket/core/thread virtual
CPU belongs to, provided if supported by board
target: SysEmuTarget
the QEMU system emulation target, which determines which addi-
tional fields will be listed (since 3.0)
The members of CpuInfoS390 when target is "s390x"
Since
2.12
query-cpus-fast (Command)
Returns information about all virtual CPUs.
Returns
list of CpuInfoFast
Since
2.12
Example
-> { "execute": "query-cpus-fast" }
<- { "return": [
{
"thread-id": 25627,
"props": {
"core-id": 0,
"thread-id": 0,
"socket-id": 0
},
"qom-path": "/machine/unattached/device[0]",
"target":"x86_64",
"cpu-index": 0
},
{
"thread-id": 25628,
"props": {
"core-id": 0,
"thread-id": 0,
"socket-id": 1
},
"qom-path": "/machine/unattached/device[2]",
"target":"x86_64",
"cpu-index": 1
}
]
}
MachineInfo (Object)
Information describing a machine.
Members
name: string
the name of the machine
alias: string (optional)
an alias for the machine name
is-default: boolean (optional)
whether the machine is default
cpu-max: int
maximum number of CPUs supported by the machine type (since 1.5)
hotpluggable-cpus: boolean
cpu hotplug via -device is supported (since 2.7)
numa-mem-supported: boolean
true if '-numa node,mem' option is supported by the machine type
and false otherwise (since 4.1)
deprecated: boolean
if true, the machine type is deprecated and may be removed in
future versions of QEMU according to the QEMU deprecation policy
(since 4.1)
default-cpu-type: string (optional)
default CPU model typename if none is requested via the -cpu ar-
gument. (since 4.2)
default-ram-id: string (optional)
the default ID of initial RAM memory backend (since 5.2)
Since
1.2
query-machines (Command)
Return a list of supported machines
Returns
a list of MachineInfo
Since
1.2
CurrentMachineParams (Object)
Information describing the running machine parameters.
Members
wakeup-suspend-support: boolean
true if the machine supports wake up from suspend
Since
4.0
query-current-machine (Command)
Return information on the current virtual machine.
Returns
CurrentMachineParams
Since
4.0
TargetInfo (Object)
Information describing the QEMU target.
Members
arch: SysEmuTarget
the target architecture
Since
1.2
query-target (Command)
Return information about the target for this QEMU
Returns
TargetInfo
Since
1.2
UuidInfo (Object)
Guest UUID information (Universally Unique Identifier).
Members
UUID: string
the UUID of the guest
Since
0.14
Notes
If no UUID was specified for the guest, a null UUID is returned.
query-uuid (Command)
Query the guest UUID information.
Returns
The UuidInfo for the guest
Since
0.14
Example
-> { "execute": "query-uuid" }
<- { "return": { "UUID": "550e8400-e29b-41d4-a716-446655440000" } }
GuidInfo (Object)
GUID information.
Members
guid: string
the globally unique identifier
Since
2.9
query-vm-generation-id (Command)
Show Virtual Machine Generation ID
Since
2.9
system_reset (Command)
Performs a hard reset of a guest.
Since
0.14
Example
-> { "execute": "system_reset" }
<- { "return": {} }
system_powerdown (Command)
Requests that a guest perform a powerdown operation.
Since
0.14
Notes
A guest may or may not respond to this command. This command returning
does not indicate that a guest has accepted the request or that it has
shut down. Many guests will respond to this command by prompting the
user in some way.
Example
-> { "execute": "system_powerdown" }
<- { "return": {} }
system_wakeup (Command)
Wake up guest from suspend. If the guest has wake-up from suspend sup-
port enabled (wakeup-suspend-support flag from query-current-machine),
wake-up guest from suspend if the guest is in SUSPENDED state. Return
an error otherwise.
Since
1.1
Returns
nothing.
Note
prior to 4.0, this command does nothing in case the guest isn't sus-
pended.
Example
-> { "execute": "system_wakeup" }
<- { "return": {} }
LostTickPolicy (Enum)
Policy for handling lost ticks in timer devices. Ticks end up getting
lost when, for example, the guest is paused.
Values
discard
throw away the missed ticks and continue with future injection
normally. The guest OS will see the timer jump ahead by a po-
tentially quite significant amount all at once, as if the inter-
vening chunk of time had simply not existed; needless to say,
such a sudden jump can easily confuse a guest OS which is not
specifically prepared to deal with it. Assuming the guest OS
can deal correctly with the time jump, the time in the guest and
in the host should now match.
delay continue to deliver ticks at the normal rate. The guest OS will
not notice anything is amiss, as from its point of view time
will have continued to flow normally. The time in the guest
should now be behind the time in the host by exactly the amount
of time during which ticks have been missed.
slew deliver ticks at a higher rate to catch up with the missed
ticks. The guest OS will not notice anything is amiss, as from
its point of view time will have continued to flow normally.
Once the timer has managed to catch up with all the missing
ticks, the time in the guest and in the host should match.
Since
2.0
inject-nmi (Command)
Injects a Non-Maskable Interrupt into the default CPU (x86/s390) or all
CPUs (ppc64). The command fails when the guest doesn't support inject-
ing.
Returns
If successful, nothing
Since
0.14
Note
prior to 2.1, this command was only supported for x86 and s390 VMs
Example
-> { "execute": "inject-nmi" }
<- { "return": {} }
KvmInfo (Object)
Information about support for KVM acceleration
Members
enabled: boolean
true if KVM acceleration is active
present: boolean
true if KVM acceleration is built into this executable
Since
0.14
query-kvm (Command)
Returns information about KVM acceleration
Returns
KvmInfo
Since
0.14
Example
-> { "execute": "query-kvm" }
<- { "return": { "enabled": true, "present": true } }
NumaOptionsType (Enum)
Values
node NUMA nodes configuration
dist NUMA distance configuration (since 2.10)
cpu property based CPU(s) to node mapping (Since: 2.10)
hmat-lb
memory latency and bandwidth information (Since: 5.0)
hmat-cache
memory side cache information (Since: 5.0)
Since
2.1
NumaOptions (Object)
A discriminated record of NUMA options. (for OptsVisitor)
Members
type: NumaOptionsType
Not documented
The members of NumaNodeOptions when type is "node"
The members of NumaDistOptions when type is "dist"
The members of NumaCpuOptions when type is "cpu"
The members of NumaHmatLBOptions when type is "hmat-lb"
The members of NumaHmatCacheOptions when type is "hmat-cache"
Since
2.1
NumaNodeOptions (Object)
Create a guest NUMA node. (for OptsVisitor)
Members
nodeid: int (optional)
NUMA node ID (increase by 1 from 0 if omitted)
cpus: array of int (optional)
VCPUs belonging to this node (assign VCPUS round-robin
if omitted)
mem: int (optional)
memory size of this node; mutually exclusive with memdev.
Equally divide total memory among nodes if both mem and memdev
are omitted.
memdev: string (optional)
memory backend object. If specified for one node, it must be
specified for all nodes.
initiator: int (optional)
defined in ACPI 6.3 Chapter 5.2.27.3 Table 5-145, points to the
nodeid which has the memory controller responsible for this NUMA
node. This field provides additional information as to the ini-
tiator node that is closest (as in directly attached) to this
node, and therefore has the best performance (since 5.0)
Since
2.1
NumaDistOptions (Object)
Set the distance between 2 NUMA nodes.
Members
src: int
source NUMA node.
dst: int
destination NUMA node.
val: int
NUMA distance from source node to destination node. When a node
is unreachable from another node, set the distance between them
to 255.
Since
2.10
CXLFixedMemoryWindowOptions (Object)
Create a CXL Fixed Memory Window
Members
size: int
Size of the Fixed Memory Window in bytes. Must be a multiple of
256MiB.
interleave-granularity: int (optional)
Number of contiguous bytes for which accesses will go to a given
interleave target. Accepted values [256, 512, 1k, 2k, 4k, 8k,
16k]
targets: array of string
Target root bridge IDs from -device ...,id=<ID> for each root
bridge.
Since 7.1
CXLFMWProperties (Object)
List of CXL Fixed Memory Windows.
Members
cxl-fmw: array of CXLFixedMemoryWindowOptions
List of CXLFixedMemoryWindowOptions
Since 7.1
X86CPURegister32 (Enum)
A X86 32-bit register
Values
EAX Not documented
EBX Not documented
ECX Not documented
EDX Not documented
ESP Not documented
EBP Not documented
ESI Not documented
EDI Not documented
Since
1.5
X86CPUFeatureWordInfo (Object)
Information about a X86 CPU feature word
Members
cpuid-input-eax: int
Input EAX value for CPUID instruction for that feature word
cpuid-input-ecx: int (optional)
Input ECX value for CPUID instruction for that feature word
cpuid-register: X86CPURegister32
Output register containing the feature bits
features: int
value of output register, containing the feature bits
Since
1.5
DummyForceArrays (Object)
Not used by QMP; hack to let us use X86CPUFeatureWordInfoList inter-
nally
Members
unused: array of X86CPUFeatureWordInfo
Not documented
Since
2.5
NumaCpuOptions (Object)
Option "-numa cpu" overrides default cpu to node mapping. It accepts
the same set of cpu properties as returned by query-hotplug-
gable-cpus[].props, where node-id could be used to override default
node mapping.
Members
The members of CpuInstanceProperties
Since
2.10
HmatLBMemoryHierarchy (Enum)
The memory hierarchy in the System Locality Latency and Bandwidth In-
formation Structure of HMAT (Heterogeneous Memory Attribute Table)
For more information about HmatLBMemoryHierarchy, see chapter 5.2.27.4:
Table 5-146: Field "Flags" of ACPI 6.3 spec.
Values
memory the structure represents the memory performance
first-level
first level of memory side cache
second-level
second level of memory side cache
third-level
third level of memory side cache
Since
5.0
HmatLBDataType (Enum)
Data type in the System Locality Latency and Bandwidth Information
Structure of HMAT (Heterogeneous Memory Attribute Table)
For more information about HmatLBDataType, see chapter 5.2.27.4: Table
5-146: Field "Data Type" of ACPI 6.3 spec.
Values
access-latency
access latency (nanoseconds)
read-latency
read latency (nanoseconds)
write-latency
write latency (nanoseconds)
access-bandwidth
access bandwidth (Bytes per second)
read-bandwidth
read bandwidth (Bytes per second)
write-bandwidth
write bandwidth (Bytes per second)
Since
5.0
NumaHmatLBOptions (Object)
Set the system locality latency and bandwidth information between Ini-
tiator and Target proximity Domains.
For more information about NumaHmatLBOptions, see chapter 5.2.27.4: Ta-
ble 5-146 of ACPI 6.3 spec.
Members
initiator: int
the Initiator Proximity Domain.
target: int
the Target Proximity Domain.
hierarchy: HmatLBMemoryHierarchy
the Memory Hierarchy. Indicates the performance of memory or
side cache.
data-type: HmatLBDataType
presents the type of data, access/read/write latency or hit la-
tency.
latency: int (optional)
the value of latency from initiator to target proximity domain,
the latency unit is "ns(nanosecond)".
bandwidth: int (optional)
the value of bandwidth between initiator and target proximity
domain, the bandwidth unit is "Bytes per second".
Since
5.0
HmatCacheAssociativity (Enum)
Cache associativity in the Memory Side Cache Information Structure of
HMAT
For more information of HmatCacheAssociativity, see chapter 5.2.27.5:
Table 5-147 of ACPI 6.3 spec.
Values
none
None (no memory side cache in this proximity domain,
or cache associativity unknown)
direct Direct Mapped
complex
Complex Cache Indexing (implementation specific)
Since
5.0
HmatCacheWritePolicy (Enum)
Cache write policy in the Memory Side Cache Information Structure of
HMAT
For more information of HmatCacheWritePolicy, see chapter 5.2.27.5: Ta-
ble 5-147: Field "Cache Attributes" of ACPI 6.3 spec.
Values
none None (no memory side cache in this proximity domain, or cache
write policy unknown)
write-back
Write Back (WB)
write-through
Write Through (WT)
Since
5.0
NumaHmatCacheOptions (Object)
Set the memory side cache information for a given memory domain.
For more information of NumaHmatCacheOptions, see chapter 5.2.27.5: Ta-
ble 5-147: Field "Cache Attributes" of ACPI 6.3 spec.
Members
node-id: int
the memory proximity domain to which the memory belongs.
size: int
the size of memory side cache in bytes.
level: int
the cache level described in this structure.
associativity: HmatCacheAssociativity
the cache associativity, none/direct-mapped/complex(complex
cache indexing).
policy: HmatCacheWritePolicy
the write policy, none/write-back/write-through.
line: int
the cache Line size in bytes.
Since
5.0
memsave (Command)
Save a portion of guest memory to a file.
Arguments
val: int
the virtual address of the guest to start from
size: int
the size of memory region to save
filename: string
the file to save the memory to as binary data
cpu-index: int (optional)
the index of the virtual CPU to use for translating the virtual
address (defaults to CPU 0)
Returns
Nothing on success
Since
0.14
Notes
Errors were not reliably returned until 1.1
Example
-> { "execute": "memsave",
"arguments": { "val": 10,
"size": 100,
"filename": "/tmp/virtual-mem-dump" } }
<- { "return": {} }
pmemsave (Command)
Save a portion of guest physical memory to a file.
Arguments
val: int
the physical address of the guest to start from
size: int
the size of memory region to save
filename: string
the file to save the memory to as binary data
Returns
Nothing on success
Since
0.14
Notes
Errors were not reliably returned until 1.1
Example
-> { "execute": "pmemsave",
"arguments": { "val": 10,
"size": 100,
"filename": "/tmp/physical-mem-dump" } }
<- { "return": {} }
Memdev (Object)
Information about memory backend
Members
id: string (optional)
backend's ID if backend has 'id' property (since 2.9)
size: int
memory backend size
merge: boolean
whether memory merge support is enabled
dump: boolean
whether memory backend's memory is included in a core dump
prealloc: boolean
whether memory was preallocated
share: boolean
whether memory is private to QEMU or shared (since 6.1)
reserve: boolean (optional)
whether swap space (or huge pages) was reserved if applicable.
This corresponds to the user configuration and not the actual
behavior implemented in the OS to perform the reservation. For
example, Linux will never reserve swap space for shared file
mappings. (since 6.1)
host-nodes: array of int
host nodes for its memory policy
policy: HostMemPolicy
memory policy of memory backend
Since
2.1
query-memdev (Command)
Returns information for all memory backends.
Returns
a list of Memdev.
Since
2.1
Example
-> { "execute": "query-memdev" }
<- { "return": [
{
"id": "mem1",
"size": 536870912,
"merge": false,
"dump": true,
"prealloc": false,
"share": false,
"host-nodes": [0, 1],
"policy": "bind"
},
{
"size": 536870912,
"merge": false,
"dump": true,
"prealloc": true,
"share": false,
"host-nodes": [2, 3],
"policy": "preferred"
}
]
}
CpuInstanceProperties (Object)
List of properties to be used for hotplugging a CPU instance, it should
be passed by management with device_add command when a CPU is being
hotplugged.
Members
node-id: int (optional)
NUMA node ID the CPU belongs to
socket-id: int (optional)
socket number within node/board the CPU belongs to
die-id: int (optional)
die number within socket the CPU belongs to (since 4.1)
cluster-id: int (optional)
cluster number within die the CPU belongs to (since 7.1)
core-id: int (optional)
core number within cluster the CPU belongs to
thread-id: int (optional)
thread number within core the CPU belongs to
Note
currently there are 6 properties that could be present but management
should be prepared to pass through other properties with device_add
command to allow for future interface extension. This also requires the
filed names to be kept in sync with the properties passed to -de-
vice/device_add.
Since
2.7
HotpluggableCPU (Object)
Members
type: string
CPU object type for usage with device_add command
props: CpuInstanceProperties
list of properties to be used for hotplugging CPU
vcpus-count: int
number of logical VCPU threads HotpluggableCPU provides
qom-path: string (optional)
link to existing CPU object if CPU is present or omitted if CPU
is not present.
Since
2.7
query-hotpluggable-cpus (Command)
TODO
Better documentation; currently there is none.
Returns
a list of HotpluggableCPU objects.
Since
2.7
Example
For pseries machine type started with -smp 2,cores=2,maxcpus=4 -cpu POWER8:
-> { "execute": "query-hotpluggable-cpus" }
<- {"return": [
{ "props": { "core-id": 8 }, "type": "POWER8-spapr-cpu-core",
"vcpus-count": 1 },
{ "props": { "core-id": 0 }, "type": "POWER8-spapr-cpu-core",
"vcpus-count": 1, "qom-path": "/machine/unattached/device[0]"}
]}'
For pc machine type started with -smp 1,maxcpus=2:
-> { "execute": "query-hotpluggable-cpus" }
<- {"return": [
{
"type": "qemu64-x86_64-cpu", "vcpus-count": 1,
"props": {"core-id": 0, "socket-id": 1, "thread-id": 0}
},
{
"qom-path": "/machine/unattached/device[0]",
"type": "qemu64-x86_64-cpu", "vcpus-count": 1,
"props": {"core-id": 0, "socket-id": 0, "thread-id": 0}
}
]}
For s390x-virtio-ccw machine type started with -smp 1,maxcpus=2 -cpu qemu
(Since: 2.11):
-> { "execute": "query-hotpluggable-cpus" }
<- {"return": [
{
"type": "qemu-s390x-cpu", "vcpus-count": 1,
"props": { "core-id": 1 }
},
{
"qom-path": "/machine/unattached/device[0]",
"type": "qemu-s390x-cpu", "vcpus-count": 1,
"props": { "core-id": 0 }
}
]}
set-numa-node (Command)
Runtime equivalent of '-numa' CLI option, available at preconfigure
stage to configure numa mapping before initializing machine.
Arguments
The members of NumaOptions
Since
3.0
balloon (Command)
Request the balloon driver to change its balloon size.
Arguments
value: int
the target logical size of the VM in bytes. We can deduce the
size of the balloon using this formula:
logical_vm_size = vm_ram_size - balloon_size
From it we have: balloon_size = vm_ram_size - value
Returns
• Nothing on success
• If the balloon driver is enabled but not functional because the KVM
kernel module cannot support it, KvmMissingCap
• If no balloon device is present, DeviceNotActive
Notes
This command just issues a request to the guest. When it returns, the
balloon size may not have changed. A guest can change the balloon size
independent of this command.
Since
0.14
Example
-> { "execute": "balloon", "arguments": { "value": 536870912 } }
<- { "return": {} }
With a 2.5GiB guest this command inflated the ballon to 3GiB.
BalloonInfo (Object)
Information about the guest balloon device.
Members
actual: int
the logical size of the VM in bytes Formula used: logi-
cal_vm_size = vm_ram_size - balloon_size
Since
0.14
query-balloon (Command)
Return information about the balloon device.
Returns
• BalloonInfo on success
• If the balloon driver is enabled but not functional because the KVM
kernel module cannot support it, KvmMissingCap
• If no balloon device is present, DeviceNotActive
Since
0.14
Example
-> { "execute": "query-balloon" }
<- { "return": {
"actual": 1073741824
}
}
BALLOON_CHANGE (Event)
Emitted when the guest changes the actual BALLOON level. This value is
equivalent to the actual field return by the 'query-balloon' command
Arguments
actual: int
the logical size of the VM in bytes Formula used: logi-
cal_vm_size = vm_ram_size - balloon_size
Note
this event is rate-limited.
Since
1.2
Example
<- { "event": "BALLOON_CHANGE",
"data": { "actual": 944766976 },
"timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
MemoryInfo (Object)
Actual memory information in bytes.
Members
base-memory: int
size of "base" memory specified with command line option -m.
plugged-memory: int (optional)
size of memory that can be hot-unplugged. This field is omitted
if target doesn't support memory hotplug (i.e. CONFIG_MEM_DEVICE
not defined at build time).
Since
2.11
query-memory-size-summary (Command)
Return the amount of initially allocated and present hotpluggable (if
enabled) memory in bytes.
Example
-> { "execute": "query-memory-size-summary" }
<- { "return": { "base-memory": 4294967296, "plugged-memory": 0 } }
Since
2.11
PCDIMMDeviceInfo (Object)
PCDIMMDevice state information
Members
id: string (optional)
device's ID
addr: int
physical address, where device is mapped
size: int
size of memory that the device provides
slot: int
slot number at which device is plugged in
node: int
NUMA node number where device is plugged in
memdev: string
memory backend linked with device
hotplugged: boolean
true if device was hotplugged
hotpluggable: boolean
true if device if could be added/removed while machine is run-
ning
Since
2.1
VirtioPMEMDeviceInfo (Object)
VirtioPMEM state information
Members
id: string (optional)
device's ID
memaddr: int
physical address in memory, where device is mapped
size: int
size of memory that the device provides
memdev: string
memory backend linked with device
Since
4.1
VirtioMEMDeviceInfo (Object)
VirtioMEMDevice state information
Members
id: string (optional)
device's ID
memaddr: int
physical address in memory, where device is mapped
requested-size: int
the user requested size of the device
size: int
the (current) size of memory that the device provides
max-size: int
the maximum size of memory that the device can provide
block-size: int
the block size of memory that the device provides
node: int
NUMA node number where device is assigned to
memdev: string
memory backend linked with the region
Since
5.1
SgxEPCDeviceInfo (Object)
Sgx EPC state information
Members
id: string (optional)
device's ID
memaddr: int
physical address in memory, where device is mapped
size: int
size of memory that the device provides
memdev: string
memory backend linked with device
node: int
the numa node (Since: 7.0)
Since
6.2
MemoryDeviceInfoKind (Enum)
Values
dimm Not documented
nvdimm Not documented
virtio-pmem
Not documented
virtio-mem
Not documented
sgx-epc
Not documented
Since
2.1
PCDIMMDeviceInfoWrapper (Object)
Members
data: PCDIMMDeviceInfo
Not documented
Since
2.1
VirtioPMEMDeviceInfoWrapper (Object)
Members
data: VirtioPMEMDeviceInfo
Not documented
Since
2.1
VirtioMEMDeviceInfoWrapper (Object)
Members
data: VirtioMEMDeviceInfo
Not documented
Since
2.1
SgxEPCDeviceInfoWrapper (Object)
Members
data: SgxEPCDeviceInfo
Not documented
Since
6.2
MemoryDeviceInfo (Object)
Union containing information about a memory device
nvdimm is included since 2.12. virtio-pmem is included since 4.1. vir-
tio-mem is included since 5.1. sgx-epc is included since 6.2.
Members
type: MemoryDeviceInfoKind
Not documented
The members of PCDIMMDeviceInfoWrapper when type is "dimm"
The members of PCDIMMDeviceInfoWrapper when type is "nvdimm"
The members of VirtioPMEMDeviceInfoWrapper when type is "virtio-pmem"
The members of VirtioMEMDeviceInfoWrapper when type is "virtio-mem"
The members of SgxEPCDeviceInfoWrapper when type is "sgx-epc"
Since
2.1
SgxEPC (Object)
Sgx EPC cmdline information
Members
memdev: string
memory backend linked with device
node: int
the numa node (Since: 7.0)
Since
6.2
SgxEPCProperties (Object)
SGX properties of machine types.
Members
sgx-epc: array of SgxEPC
list of ids of memory-backend-epc objects.
Since
6.2
query-memory-devices (Command)
Lists available memory devices and their state
Since
2.1
Example
-> { "execute": "query-memory-devices" }
<- { "return": [ { "data":
{ "addr": 5368709120,
"hotpluggable": true,
"hotplugged": true,
"id": "d1",
"memdev": "/objects/memX",
"node": 0,
"size": 1073741824,
"slot": 0},
"type": "dimm"
} ] }
MEMORY_DEVICE_SIZE_CHANGE (Event)
Emitted when the size of a memory device changes. Only emitted for mem-
ory devices that can actually change the size (e.g., virtio-mem due to
guest action).
Arguments
id: string (optional)
device's ID
size: int
the new size of memory that the device provides
qom-path: string
path to the device object in the QOM tree (since 6.2)
Note
this event is rate-limited.
Since
5.1
Example
<- { "event": "MEMORY_DEVICE_SIZE_CHANGE",
"data": { "id": "vm0", "size": 1073741824,
"qom-path": "/machine/unattached/device[2]" },
"timestamp": { "seconds": 1588168529, "microseconds": 201316 } }
MEM_UNPLUG_ERROR (Event)
Emitted when memory hot unplug error occurs.
Arguments
device: string
device name
msg: string
Informative message
Features
deprecated
This event is deprecated. Use DEVICE_UNPLUG_GUEST_ERROR instead.
Since
2.4
Example
<- { "event": "MEM_UNPLUG_ERROR",
"data": { "device": "dimm1",
"msg": "acpi: device unplug for unsupported device"
},
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
BootConfiguration (Object)
Schema for virtual machine boot configuration.
Members
order: string (optional)
Boot order (a=floppy, c=hard disk, d=CD-ROM, n=network)
once: string (optional)
Boot order to apply on first boot
menu: boolean (optional)
Whether to show a boot menu
splash: string (optional)
The name of the file to be passed to the firmware as logo pic-
ture, if menu is true.
splash-time: int (optional)
How long to show the logo picture, in milliseconds
reboot-timeout: int (optional)
Timeout before guest reboots after boot fails
strict: boolean (optional)
Whether to attempt booting from devices not included in the boot
order
Since
7.1
SMPConfiguration (Object)
Schema for CPU topology configuration. A missing value lets QEMU fig-
ure out a suitable value based on the ones that are provided.
Members
cpus: int (optional)
number of virtual CPUs in the virtual machine
sockets: int (optional)
number of sockets in the CPU topology
dies: int (optional)
number of dies per socket in the CPU topology
clusters: int (optional)
number of clusters per die in the CPU topology (since 7.0)
cores: int (optional)
number of cores per cluster in the CPU topology
threads: int (optional)
number of threads per core in the CPU topology
maxcpus: int (optional)
maximum number of hotpluggable virtual CPUs in the virtual ma-
chine
Since
6.1
x-query-irq (Command)
Query interrupt statistics
Features
unstable
This command is meant for debugging.
Returns
interrupt statistics
Since
6.2
x-query-jit (Command)
Query TCG compiler statistics
Features
unstable
This command is meant for debugging.
Returns
TCG compiler statistics
Since
6.2
If
CONFIG_TCG
x-query-numa (Command)
Query NUMA topology information
Features
unstable
This command is meant for debugging.
Returns
topology information
Since
6.2
x-query-opcount (Command)
Query TCG opcode counters
Features
unstable
This command is meant for debugging.
Returns
TCG opcode counters
Since
6.2
If
CONFIG_TCG
x-query-profile (Command)
Query TCG profiling information
Features
unstable
This command is meant for debugging.
Returns
profile information
Since
6.2
If
CONFIG_TCG
x-query-ramblock (Command)
Query system ramblock information
Features
unstable
This command is meant for debugging.
Returns
system ramblock information
Since
6.2
x-query-rdma (Command)
Query RDMA state
Features
unstable
This command is meant for debugging.
Returns
RDMA state
Since
6.2
x-query-roms (Command)
Query information on the registered ROMS
Features
unstable
This command is meant for debugging.
Returns
registered ROMs
Since
6.2
x-query-usb (Command)
Query information on the USB devices
Features
unstable
This command is meant for debugging.
Returns
USB device information
Since
6.2
SmbiosEntryPointType (Enum)
Values
32 SMBIOS version 2.1 (32-bit) Entry Point
64 SMBIOS version 3.0 (64-bit) Entry Point
Since
7.0
MemorySizeConfiguration (Object)
Schema for memory size configuration.
Members
size: int (optional)
memory size in bytes
max-size: int (optional)
maximum hotpluggable memory size in bytes
slots: int (optional)
number of available memory slots for hotplug
Since
7.1
dumpdtb (Command)
Save the FDT in dtb format.
Arguments
filename: string
name of the dtb file to be created
Since
7.2
Example
{"execute": "dumpdtb"}
"arguments": { "filename": "fdt.dtb" } }
If
CONFIG_FDT
CpuModelInfo (Object)
Virtual CPU model.
A CPU model consists of the name of a CPU definition, to which delta
changes are applied (e.g. features added/removed). Most magic values
that an architecture might require should be hidden behind the name.
However, if required, architectures can expose relevant properties.
Members
name: string
the name of the CPU definition the model is based on
props: value (optional)
a dictionary of QOM properties to be applied
Since
2.8
CpuModelExpansionType (Enum)
An enumeration of CPU model expansion types.
Values
static Expand to a static CPU model, a combination of a static base
model name and property delta changes. As the static base model
will never change, the expanded CPU model will be the same, in-
dependent of QEMU version, machine type, machine options, and
accelerator options. Therefore, the resulting model can be used
by tooling without having to specify a compatibility machine -
e.g. when displaying the "host" model. The static CPU models are
migration-safe.
full Expand all properties. The produced model is not guaranteed to
be migration-safe, but allows tooling to get an insight and work
with model details.
Note
When a non-migration-safe CPU model is expanded in static mode, some
features enabled by the CPU model may be omitted, because they can't be
implemented by a static CPU model definition (e.g. cache info
passthrough and PMU passthrough in x86). If you need an accurate repre-
sentation of the features enabled by a non-migration-safe CPU model,
use full. If you need a static representation that will keep ABI com-
patibility even when changing QEMU version or machine-type, use static
(but keep in mind that some features may be omitted).
Since
2.8
CpuModelCompareResult (Enum)
An enumeration of CPU model comparison results. The result is usually
calculated using e.g. CPU features or CPU generations.
Values
incompatible
If model A is incompatible to model B, model A is not guaranteed
to run where model B runs and the other way around.
identical
If model A is identical to model B, model A is guaranteed to run
where model B runs and the other way around.
superset
If model A is a superset of model B, model B is guaranteed to
run where model A runs. There are no guarantees about the other
way.
subset If model A is a subset of model B, model A is guaranteed to run
where model B runs. There are no guarantees about the other way.
Since
2.8
CpuModelBaselineInfo (Object)
The result of a CPU model baseline.
Members
model: CpuModelInfo
the baselined CpuModelInfo.
Since
2.8
If
TARGET_S390X
CpuModelCompareInfo (Object)
The result of a CPU model comparison.
Members
result: CpuModelCompareResult
The result of the compare operation.
responsible-properties: array of string
List of properties that led to the comparison result not being
identical.
responsible-properties is a list of QOM property names that led to both
CPUs not being detected as identical. For identical models, this list
is empty. If a QOM property is read-only, that means there's no known
way to make the CPU models identical. If the special property name
"type" is included, the models are by definition not identical and can-
not be made identical.
Since
2.8
If
TARGET_S390X
query-cpu-model-comparison (Command)
Compares two CPU models, returning how they compare in a specific con-
figuration. The results indicates how both models compare regarding
runnability. This result can be used by tooling to make decisions if a
certain CPU model will run in a certain configuration or if a compati-
ble CPU model has to be created by baselining.
Usually, a CPU model is compared against the maximum possible CPU model
of a certain configuration (e.g. the "host" model for KVM). If that CPU
model is identical or a subset, it will run in that configuration.
The result returned by this command may be affected by:
• QEMU version: CPU models may look different depending on the QEMU
version. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine-type: CPU model may look different depending on the ma-
chine-type. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine options (including accelerator): in some architectures, CPU
models may look different depending on machine and accelerator op-
tions. (Except for CPU models reported as "static" in query-cpu-defi-
nitions.)
• "-cpu" arguments and global properties: arguments to the -cpu option
and global properties may affect expansion of CPU models. Using
query-cpu-model-expansion while using these is not advised.
Some architectures may not support comparing CPU models. s390x supports
comparing CPU models.
Arguments
modela: CpuModelInfo
Not documented
modelb: CpuModelInfo
Not documented
Returns
a CpuModelBaselineInfo. Returns an error if comparing CPU models is not
supported, if a model cannot be used, if a model contains an unknown
cpu definition name, unknown properties or properties with wrong types.
Note
this command isn't specific to s390x, but is only implemented on this
architecture currently.
Since
2.8
If
TARGET_S390X
query-cpu-model-baseline (Command)
Baseline two CPU models, creating a compatible third model. The created
model will always be a static, migration-safe CPU model (see "static"
CPU model expansion for details).
This interface can be used by tooling to create a compatible CPU model
out two CPU models. The created CPU model will be identical to or a
subset of both CPU models when comparing them. Therefore, the created
CPU model is guaranteed to run where the given CPU models run.
The result returned by this command may be affected by:
• QEMU version: CPU models may look different depending on the QEMU
version. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine-type: CPU model may look different depending on the ma-
chine-type. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine options (including accelerator): in some architectures, CPU
models may look different depending on machine and accelerator op-
tions. (Except for CPU models reported as "static" in query-cpu-defi-
nitions.)
• "-cpu" arguments and global properties: arguments to the -cpu option
and global properties may affect expansion of CPU models. Using
query-cpu-model-expansion while using these is not advised.
Some architectures may not support baselining CPU models. s390x sup-
ports baselining CPU models.
Arguments
modela: CpuModelInfo
Not documented
modelb: CpuModelInfo
Not documented
Returns
a CpuModelBaselineInfo. Returns an error if baselining CPU models is
not supported, if a model cannot be used, if a model contains an un-
known cpu definition name, unknown properties or properties with wrong
types.
Note
this command isn't specific to s390x, but is only implemented on this
architecture currently.
Since
2.8
If
TARGET_S390X
CpuModelExpansionInfo (Object)
The result of a cpu model expansion.
Members
model: CpuModelInfo
the expanded CpuModelInfo.
Since
2.8
If
TARGET_S390X or TARGET_I386 or TARGET_ARM
query-cpu-model-expansion (Command)
Expands a given CPU model (or a combination of CPU model + additional
options) to different granularities, allowing tooling to get an under-
standing what a specific CPU model looks like in QEMU under a certain
configuration.
This interface can be used to query the "host" CPU model.
The data returned by this command may be affected by:
• QEMU version: CPU models may look different depending on the QEMU
version. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine-type: CPU model may look different depending on the ma-
chine-type. (Except for CPU models reported as "static" in
query-cpu-definitions.)
• machine options (including accelerator): in some architectures, CPU
models may look different depending on machine and accelerator op-
tions. (Except for CPU models reported as "static" in query-cpu-defi-
nitions.)
• "-cpu" arguments and global properties: arguments to the -cpu option
and global properties may affect expansion of CPU models. Using
query-cpu-model-expansion while using these is not advised.
Some architectures may not support all expansion types. s390x supports
"full" and "static". Arm only supports "full".
Arguments
type: CpuModelExpansionType
Not documented
model: CpuModelInfo
Not documented
Returns
a CpuModelExpansionInfo. Returns an error if expanding CPU models is
not supported, if the model cannot be expanded, if the model contains
an unknown CPU definition name, unknown properties or properties with a
wrong type. Also returns an error if an expansion type is not sup-
ported.
Since
2.8
If
TARGET_S390X or TARGET_I386 or TARGET_ARM
CpuDefinitionInfo (Object)
Virtual CPU definition.
Members
name: string
the name of the CPU definition
migration-safe: boolean (optional)
whether a CPU definition can be safely used for migration in
combination with a QEMU compatibility machine when migrating be-
tween different QEMU versions and between hosts with different
sets of (hardware or software) capabilities. If not provided,
information is not available and callers should not assume the
CPU definition to be migration-safe. (since 2.8)
static: boolean
whether a CPU definition is static and will not change depending
on QEMU version, machine type, machine options and accelerator
options. A static model is always migration-safe. (since 2.8)
unavailable-features: array of string (optional)
List of properties that prevent the CPU model from running in
the current host. (since 2.8)
typename: string
Type name that can be used as argument to device-list-proper-
ties, to introspect properties configurable using -cpu or
-global. (since 2.9)
alias-of: string (optional)
Name of CPU model this model is an alias for. The target of the
CPU model alias may change depending on the machine type. Man-
agement software is supposed to translate CPU model aliases in
the VM configuration, because aliases may stop being migra-
tion-safe in the future (since 4.1)
deprecated: boolean
If true, this CPU model is deprecated and may be removed in in
some future version of QEMU according to the QEMU deprecation
policy. (since 5.2)
unavailable-features is a list of QOM property names that represent CPU
model attributes that prevent the CPU from running. If the QOM prop-
erty is read-only, that means there's no known way to make the CPU
model run in the current host. Implementations that choose not to pro-
vide specific information return the property name "type". If the
property is read-write, it means that it MAY be possible to run the CPU
model in the current host if that property is changed. Management soft-
ware can use it as hints to suggest or choose an alternative for the
user, or just to generate meaningful error messages explaining why the
CPU model can't be used. If unavailable-features is an empty list, the
CPU model is runnable using the current host and machine-type. If un-
available-features is not present, runnability information for the CPU
is not available.
Since
1.2
If
TARGET_PPC or TARGET_ARM or TARGET_I386 or TARGET_S390X or TARGET_MIPS
or TARGET_LOONGARCH64
query-cpu-definitions (Command)
Return a list of supported virtual CPU definitions
Returns
a list of CpuDefInfo
Since
1.2
If
TARGET_PPC or TARGET_ARM or TARGET_I386 or TARGET_S390X or TARGET_MIPS
or TARGET_LOONGARCH64
RECORD/REPLAY
ReplayMode (Enum)
Mode of the replay subsystem.
Values
none normal execution mode. Replay or record are not enabled.
record record mode. All non-deterministic data is written into the re-
play log.
play replay mode. Non-deterministic data required for system execu-
tion is read from the log.
Since
2.5
ReplayInfo (Object)
Record/replay information.
Members
mode: ReplayMode
current mode.
filename: string (optional)
name of the record/replay log file. It is present only in
record or replay modes, when the log is recorded or replayed.
icount: int
current number of executed instructions.
Since
5.2
query-replay (Command)
Retrieve the record/replay information. It includes current instruc-
tion count which may be used for replay-break and replay-seek commands.
Returns
record/replay information.
Since
5.2
Example
-> { "execute": "query-replay" }
<- { "return": { "mode": "play", "filename": "log.rr", "icount": 220414 } }
replay-break (Command)
Set replay breakpoint at instruction count icount. Execution stops
when the specified instruction is reached. There can be at most one
breakpoint. When breakpoint is set, any prior one is removed. The
breakpoint may be set only in replay mode and only "in the future",
i.e. at instruction counts greater than the current one. The current
instruction count can be observed with query-replay.
Arguments
icount: int
instruction count to stop at
Since
5.2
Example
-> { "execute": "replay-break", "arguments": { "icount": 220414 } }
replay-delete-break (Command)
Remove replay breakpoint which was set with replay-break. The command
is ignored when there are no replay breakpoints.
Since
5.2
Example
-> { "execute": "replay-delete-break" }
replay-seek (Command)
Automatically proceed to the instruction count icount, when replaying
the execution. The command automatically loads nearest snapshot and re-
plays the execution to find the desired instruction. When there is no
preceding snapshot or the execution is not replayed, then the command
fails. icount for the reference may be obtained with query-replay com-
mand.
Arguments
icount: int
target instruction count
Since
5.2
Example
-> { "execute": "replay-seek", "arguments": { "icount": 220414 } }
YANK FEATURE
YankInstanceType (Enum)
An enumeration of yank instance types. See YankInstance for more infor-
mation.
Values
block-node
Not documented
chardev
Not documented
migration
Not documented
Since
6.0
YankInstanceBlockNode (Object)
Specifies which block graph node to yank. See YankInstance for more in-
formation.
Members
node-name: string
the name of the block graph node
Since
6.0
YankInstanceChardev (Object)
Specifies which character device to yank. See YankInstance for more in-
formation.
Members
id: string
the chardev's ID
Since
6.0
YankInstance (Object)
A yank instance can be yanked with the yank qmp command to recover from
a hanging QEMU.
Currently implemented yank instances:
• nbd block device: Yanking it will shut down the connection to
the nbd server without attempting to reconnect.
• socket chardev: Yanking it will shut down the connected
socket.
• migration: Yanking it will shut down all migration connec-
tions. Unlike migrate_cancel, it will not notify the migration
process, so migration will go into failed state, instead of
cancelled state. yank should be used to recover from hangs.
Members
type: YankInstanceType
Not documented
The members of YankInstanceBlockNode when type is "block-node"
The members of YankInstanceChardev when type is "chardev"
Since
6.0
yank (Command)
Try to recover from hanging QEMU by yanking the specified instances.
See YankInstance for more information.
Takes a list of YankInstance as argument.
Arguments
instances: array of YankInstance
Not documented
Returns
• Nothing on success
• DeviceNotFound error, if any of the YankInstances doesn't exist
Example
-> { "execute": "yank",
"arguments": {
"instances": [
{ "type": "block-node",
"node-name": "nbd0" }
] } }
<- { "return": {} }
Since
6.0
query-yank (Command)
Query yank instances. See YankInstance for more information.
Returns
list of YankInstance
Example
-> { "execute": "query-yank" }
<- { "return": [
{ "type": "block-node",
"node-name": "nbd0" }
] }
Since
6.0
MISCELLANEA
add_client (Command)
Allow client connections for VNC, Spice and socket based character de-
vices to be passed in to QEMU via SCM_RIGHTS.
Arguments
protocol: string
protocol name. Valid names are "vnc", "spice", "dbus-display" or
the name of a character device (eg. from -chardev id=XXXX)
fdname: string
file descriptor name previously passed via 'getfd' command
skipauth: boolean (optional)
whether to skip authentication. Only applies to "vnc" and
"spice" protocols
tls: boolean (optional)
whether to perform TLS. Only applies to the "spice" protocol
Returns
nothing on success.
Since
0.14
Example
-> { "execute": "add_client", "arguments": { "protocol": "vnc",
"fdname": "myclient" } }
<- { "return": {} }
NameInfo (Object)
Guest name information.
Members
name: string (optional)
The name of the guest
Since
0.14
query-name (Command)
Return the name information of a guest.
Returns
NameInfo of the guest
Since
0.14
Example
-> { "execute": "query-name" }
<- { "return": { "name": "qemu-name" } }
IOThreadInfo (Object)
Information about an iothread
Members
id: string
the identifier of the iothread
thread-id: int
ID of the underlying host thread
poll-max-ns: int
maximum polling time in ns, 0 means polling is disabled (since
2.9)
poll-grow: int
how many ns will be added to polling time, 0 means that it's not
configured (since 2.9)
poll-shrink: int
how many ns will be removed from polling time, 0 means that it's
not configured (since 2.9)
aio-max-batch: int
maximum number of requests in a batch for the AIO engine, 0
means that the engine will use its default (since 6.1)
Since
2.0
query-iothreads (Command)
Returns a list of information about each iothread.
Note
this list excludes the QEMU main loop thread, which is not declared us-
ing the -object iothread command-line option. It is always the main
thread of the process.
Returns
a list of IOThreadInfo for each iothread
Since
2.0
Example
-> { "execute": "query-iothreads" }
<- { "return": [
{
"id":"iothread0",
"thread-id":3134
},
{
"id":"iothread1",
"thread-id":3135
}
]
}
stop (Command)
Stop all guest VCPU execution.
Since
0.14
Notes
This function will succeed even if the guest is already in the stopped
state. In "inmigrate" state, it will ensure that the guest remains
paused once migration finishes, as if the -S option was passed on the
command line.
Example
-> { "execute": "stop" }
<- { "return": {} }
cont (Command)
Resume guest VCPU execution.
Since
0.14
Returns
If successful, nothing
Notes
This command will succeed if the guest is currently running. It will
also succeed if the guest is in the "inmigrate" state; in this case,
the effect of the command is to make sure the guest starts once migra-
tion finishes, removing the effect of the -S command line option if it
was passed.
Example
-> { "execute": "cont" }
<- { "return": {} }
x-exit-preconfig (Command)
Exit from "preconfig" state
This command makes QEMU exit the preconfig state and proceed with VM
initialization using configuration data provided on the command line
and via the QMP monitor during the preconfig state. The command is only
available during the preconfig state (i.e. when the --preconfig command
line option was in use).
Features
unstable
This command is experimental.
Since
3.0
Returns
nothing
Example
-> { "execute": "x-exit-preconfig" }
<- { "return": {} }
human-monitor-command (Command)
Execute a command on the human monitor and return the output.
Arguments
command-line: string
the command to execute in the human monitor
cpu-index: int (optional)
The CPU to use for commands that require an implicit CPU
Features
savevm-monitor-nodes
If present, HMP command savevm only snapshots monitor-owned
nodes if they have no parents. This allows the use of 'savevm'
with -blockdev. (since 4.2)
Returns
the output of the command as a string
Since
0.14
Notes
This command only exists as a stop-gap. Its use is highly discouraged.
The semantics of this command are not guaranteed: this means that com-
mand names, arguments and responses can change or be removed at ANY
time. Applications that rely on long term stability guarantees should
NOT use this command.
Known limitations:
• This command is stateless, this means that commands that depend on
state information (such as getfd) might not work
• Commands that prompt the user for data don't currently work
Example
-> { "execute": "human-monitor-command",
"arguments": { "command-line": "info kvm" } }
<- { "return": "kvm support: enabled\r\n" }
getfd (Command)
Receive a file descriptor via SCM rights and assign it a name
Arguments
fdname: string
file descriptor name
Returns
Nothing on success
Since
0.14
Notes
If fdname already exists, the file descriptor assigned to it will be
closed and replaced by the received file descriptor.
The 'closefd' command can be used to explicitly close the file descrip-
tor when it is no longer needed.
Example
-> { "execute": "getfd", "arguments": { "fdname": "fd1" } }
<- { "return": {} }
closefd (Command)
Close a file descriptor previously passed via SCM rights
Arguments
fdname: string
file descriptor name
Returns
Nothing on success
Since
0.14
Example
-> { "execute": "closefd", "arguments": { "fdname": "fd1" } }
<- { "return": {} }
AddfdInfo (Object)
Information about a file descriptor that was added to an fd set.
Members
fdset-id: int
The ID of the fd set that fd was added to.
fd: int
The file descriptor that was received via SCM rights and added
to the fd set.
Since
1.2
add-fd (Command)
Add a file descriptor, that was passed via SCM rights, to an fd set.
Arguments
fdset-id: int (optional)
The ID of the fd set to add the file descriptor to.
opaque: string (optional)
A free-form string that can be used to describe the fd.
Returns
• AddfdInfo on success
• If file descriptor was not received, FdNotSupplied
• If fdset-id is a negative value, InvalidParameterValue
Notes
The list of fd sets is shared by all monitor connections.
If fdset-id is not specified, a new fd set will be created.
Since
1.2
Example
-> { "execute": "add-fd", "arguments": { "fdset-id": 1 } }
<- { "return": { "fdset-id": 1, "fd": 3 } }
remove-fd (Command)
Remove a file descriptor from an fd set.
Arguments
fdset-id: int
The ID of the fd set that the file descriptor belongs to.
fd: int (optional)
The file descriptor that is to be removed.
Returns
• Nothing on success
• If fdset-id or fd is not found, FdNotFound
Since
1.2
Notes
The list of fd sets is shared by all monitor connections.
If fd is not specified, all file descriptors in fdset-id will be re-
moved.
Example
-> { "execute": "remove-fd", "arguments": { "fdset-id": 1, "fd": 3 } }
<- { "return": {} }
FdsetFdInfo (Object)
Information about a file descriptor that belongs to an fd set.
Members
fd: int
The file descriptor value.
opaque: string (optional)
A free-form string that can be used to describe the fd.
Since
1.2
FdsetInfo (Object)
Information about an fd set.
Members
fdset-id: int
The ID of the fd set.
fds: array of FdsetFdInfo
A list of file descriptors that belong to this fd set.
Since
1.2
query-fdsets (Command)
Return information describing all fd sets.
Returns
A list of FdsetInfo
Since
1.2
Note
The list of fd sets is shared by all monitor connections.
Example
-> { "execute": "query-fdsets" }
<- { "return": [
{
"fds": [
{
"fd": 30,
"opaque": "rdonly:/path/to/file"
},
{
"fd": 24,
"opaque": "rdwr:/path/to/file"
}
],
"fdset-id": 1
},
{
"fds": [
{
"fd": 28
},
{
"fd": 29
}
],
"fdset-id": 0
}
]
}
CommandLineParameterType (Enum)
Possible types for an option parameter.
Values
string accepts a character string
boolean
accepts "on" or "off"
number accepts a number
size accepts a number followed by an optional suffix (K)ilo, (M)ega,
(G)iga, (T)era
Since
1.5
CommandLineParameterInfo (Object)
Details about a single parameter of a command line option.
Members
name: string
parameter name
type: CommandLineParameterType
parameter CommandLineParameterType
help: string (optional)
human readable text string, not suitable for parsing.
default: string (optional)
default value string (since 2.1)
Since
1.5
CommandLineOptionInfo (Object)
Details about a command line option, including its list of parameter
details
Members
option: string
option name
parameters: array of CommandLineParameterInfo
an array of CommandLineParameterInfo
Since
1.5
query-command-line-options (Command)
Query command line option schema.
Arguments
option: string (optional)
option name
Returns
list of CommandLineOptionInfo for all options (or for the given op-
tion). Returns an error if the given option doesn't exist.
Since
1.5
Example
-> { "execute": "query-command-line-options",
"arguments": { "option": "option-rom" } }
<- { "return": [
{
"parameters": [
{
"name": "romfile",
"type": "string"
},
{
"name": "bootindex",
"type": "number"
}
],
"option": "option-rom"
}
]
}
RTC_CHANGE (Event)
Emitted when the guest changes the RTC time.
Arguments
offset: int
offset in seconds between base RTC clock (as specified by -rtc
base), and new RTC clock value
qom-path: string
path to the RTC object in the QOM tree
Note
This event is rate-limited. It is not guaranteed that the RTC in the
system implements this event, or even that the system has an RTC at
all.
Since
0.13
Example
<- { "event": "RTC_CHANGE",
"data": { "offset": 78 },
"timestamp": { "seconds": 1267020223, "microseconds": 435656 } }
VFU_CLIENT_HANGUP (Event)
Emitted when the client of a TYPE_VFIO_USER_SERVER closes the communi-
cation channel
Arguments
vfu-id: string
ID of the TYPE_VFIO_USER_SERVER object. It is the last component
of vfu-qom-path referenced below
vfu-qom-path: string
path to the TYPE_VFIO_USER_SERVER object in the QOM tree
dev-id: string
ID of attached PCI device
dev-qom-path: string
path to attached PCI device in the QOM tree
Since
7.1
Example
<- { "event": "VFU_CLIENT_HANGUP",
"data": { "vfu-id": "vfu1",
"vfu-qom-path": "/objects/vfu1",
"dev-id": "sas1",
"dev-qom-path": "/machine/peripheral/sas1" },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
rtc-reset-reinjection (Command)
This command will reset the RTC interrupt reinjection backlog. Can be
used if another mechanism to synchronize guest time is in effect, for
example QEMU guest agent's guest-set-time command.
Since
2.1
Example
-> { "execute": "rtc-reset-reinjection" }
<- { "return": {} }
If
TARGET_I386
SevState (Enum)
An enumeration of SEV state information used during query-sev.
Values
uninit The guest is uninitialized.
launch-update
The guest is currently being launched; plaintext data and regis-
ter state is being imported.
launch-secret
The guest is currently being launched; ciphertext data is being
imported.
running
The guest is fully launched or migrated in.
send-update
The guest is currently being migrated out to another machine.
receive-update
The guest is currently being migrated from another machine.
Since
2.12
If
TARGET_I386
SevInfo (Object)
Information about Secure Encrypted Virtualization (SEV) support
Members
enabled: boolean
true if SEV is active
api-major: int
SEV API major version
api-minor: int
SEV API minor version
build-id: int
SEV FW build id
policy: int
SEV policy value
state: SevState
SEV guest state
handle: int
SEV firmware handle
Since
2.12
If
TARGET_I386
query-sev (Command)
Returns information about SEV
Returns
SevInfo
Since
2.12
Example
-> { "execute": "query-sev" }
<- { "return": { "enabled": true, "api-major" : 0, "api-minor" : 0,
"build-id" : 0, "policy" : 0, "state" : "running",
"handle" : 1 } }
If
TARGET_I386
SevLaunchMeasureInfo (Object)
SEV Guest Launch measurement information
Members
data: string
the measurement value encoded in base64
Since
2.12
If
TARGET_I386
query-sev-launch-measure (Command)
Query the SEV guest launch information.
Returns
The SevLaunchMeasureInfo for the guest
Since
2.12
Example
-> { "execute": "query-sev-launch-measure" }
<- { "return": { "data": "4l8LXeNlSPUDlXPJG5966/8%YZ" } }
If
TARGET_I386
SevCapability (Object)
The struct describes capability for a Secure Encrypted Virtualization
feature.
Members
pdh: string
Platform Diffie-Hellman key (base64 encoded)
cert-chain: string
PDH certificate chain (base64 encoded)
cpu0-id: string
Unique ID of CPU0 (base64 encoded) (since 7.1)
cbitpos: int
C-bit location in page table entry
reduced-phys-bits: int
Number of physical Address bit reduction when SEV is enabled
Since
2.12
If
TARGET_I386
query-sev-capabilities (Command)
This command is used to get the SEV capabilities, and is supported on
AMD X86 platforms only.
Returns
SevCapability objects.
Since
2.12
Example
-> { "execute": "query-sev-capabilities" }
<- { "return": { "pdh": "8CCDD8DDD", "cert-chain": "888CCCDDDEE",
"cpu0-id": "2lvmGwo+...61iEinw==",
"cbitpos": 47, "reduced-phys-bits": 5}}
If
TARGET_I386
sev-inject-launch-secret (Command)
This command injects a secret blob into memory of SEV guest.
Arguments
packet-header: string
the launch secret packet header encoded in base64
secret: string
the launch secret data to be injected encoded in base64
gpa: int (optional)
the guest physical address where secret will be injected.
Since
6.0
If
TARGET_I386
SevAttestationReport (Object)
The struct describes attestation report for a Secure Encrypted Virtual-
ization feature.
Members
data: string
guest attestation report (base64 encoded)
Since
6.1
If
TARGET_I386
query-sev-attestation-report (Command)
This command is used to get the SEV attestation report, and is sup-
ported on AMD X86 platforms only.
Arguments
mnonce: string
a random 16 bytes value encoded in base64 (it will be included
in report)
Returns
SevAttestationReport objects.
Since
6.1
Example
-> { "execute" : "query-sev-attestation-report",
"arguments": { "mnonce": "aaaaaaa" } }
<- { "return" : { "data": "aaaaaaaabbbddddd"} }
If
TARGET_I386
dump-skeys (Command)
Dump guest's storage keys
Arguments
filename: string
the path to the file to dump to
This command is only supported on s390 architecture.
Since
2.5
Example
-> { "execute": "dump-skeys",
"arguments": { "filename": "/tmp/skeys" } }
<- { "return": {} }
If
TARGET_S390X
GICCapability (Object)
The struct describes capability for a specific GIC (Generic Interrupt
Controller) version. These bits are not only decided by QEMU/KVM soft-
ware version, but also decided by the hardware that the program is run-
ning upon.
Members
version: int
version of GIC to be described. Currently, only 2 and 3 are sup-
ported.
emulated: boolean
whether current QEMU/hardware supports emulated GIC device in
user space.
kernel: boolean
whether current QEMU/hardware supports hardware accelerated GIC
device in kernel.
Since
2.6
If
TARGET_ARM
query-gic-capabilities (Command)
This command is ARM-only. It will return a list of GICCapability ob-
jects that describe its capability bits.
Returns
a list of GICCapability objects.
Since
2.6
Example
-> { "execute": "query-gic-capabilities" }
<- { "return": [{ "version": 2, "emulated": true, "kernel": false },
{ "version": 3, "emulated": false, "kernel": true } ] }
If
TARGET_ARM
SGXEPCSection (Object)
Information about intel SGX EPC section info
Members
node: int
the numa node
size: int
the size of EPC section
Since
7.0
SGXInfo (Object)
Information about intel Safe Guard eXtension (SGX) support
Members
sgx: boolean
true if SGX is supported
sgx1: boolean
true if SGX1 is supported
sgx2: boolean
true if SGX2 is supported
flc: boolean
true if FLC is supported
section-size: int
The EPC section size for guest Redundant with sections. Just
for backward compatibility.
sections: array of SGXEPCSection
The EPC sections info for guest (Since: 7.0)
Features
deprecated
Member section-size is deprecated. Use sections instead.
Since
6.2
If
TARGET_I386
query-sgx (Command)
Returns information about SGX
Returns
SGXInfo
Since
6.2
Example
-> { "execute": "query-sgx" }
<- { "return": { "sgx": true, "sgx1" : true, "sgx2" : true,
"flc": true, "section-size" : 96468992,
"sections": [{"node": 0, "size": 67108864},
{"node": 1, "size": 29360128}]} }
If
TARGET_I386
query-sgx-capabilities (Command)
Returns information from host SGX capabilities
Returns
SGXInfo
Since
6.2
Example
-> { "execute": "query-sgx-capabilities" }
<- { "return": { "sgx": true, "sgx1" : true, "sgx2" : true,
"flc": true, "section-size" : 96468992,
"section" : [{"node": 0, "size": 67108864},
{"node": 1, "size": 29360128}]} }
If
TARGET_I386
AUDIO
AudiodevPerDirectionOptions (Object)
General audio backend options that are used for both playback and
recording.
Members
mixing-engine: boolean (optional)
use QEMU's mixing engine to mix all streams inside QEMU and con-
vert audio formats when not supported by the backend. When set
to off, fixed-settings must be also off (default on, since 4.2)
fixed-settings: boolean (optional)
use fixed settings for host input/output. When off, frequency,
channels and format must not be specified (default true)
frequency: int (optional)
frequency to use when using fixed settings (default 44100)
channels: int (optional)
number of channels when using fixed settings (default 2)
voices: int (optional)
number of voices to use (default 1)
format: AudioFormat (optional)
sample format to use when using fixed settings (default s16)
buffer-length: int (optional)
the buffer length in microseconds
Since
4.0
AudiodevGenericOptions (Object)
Generic driver-specific options.
Members
in: AudiodevPerDirectionOptions (optional)
options of the capture stream
out: AudiodevPerDirectionOptions (optional)
options of the playback stream
Since
4.0
AudiodevAlsaPerDirectionOptions (Object)
Options of the ALSA backend that are used for both playback and record-
ing.
Members
dev: string (optional)
the name of the ALSA device to use (default 'default')
period-length: int (optional)
the period length in microseconds
try-poll: boolean (optional)
attempt to use poll mode, falling back to non-polling access on
failure (default true)
The members of AudiodevPerDirectionOptions
Since
4.0
AudiodevAlsaOptions (Object)
Options of the ALSA audio backend.
Members
in: AudiodevAlsaPerDirectionOptions (optional)
options of the capture stream
out: AudiodevAlsaPerDirectionOptions (optional)
options of the playback stream
threshold: int (optional)
set the threshold (in microseconds) when playback starts
Since
4.0
AudiodevSndioOptions (Object)
Options of the sndio audio backend.
Members
in: AudiodevPerDirectionOptions (optional)
options of the capture stream
out: AudiodevPerDirectionOptions (optional)
options of the playback stream
dev: string (optional)
the name of the sndio device to use (default 'default')
latency: int (optional)
play buffer size (in microseconds)
Since
7.2
AudiodevCoreaudioPerDirectionOptions (Object)
Options of the Core Audio backend that are used for both playback and
recording.
Members
buffer-count: int (optional)
number of buffers
The members of AudiodevPerDirectionOptions
Since
4.0
AudiodevCoreaudioOptions (Object)
Options of the coreaudio audio backend.
Members
in: AudiodevCoreaudioPerDirectionOptions (optional)
options of the capture stream
out: AudiodevCoreaudioPerDirectionOptions (optional)
options of the playback stream
Since
4.0
AudiodevDsoundOptions (Object)
Options of the DirectSound audio backend.
Members
in: AudiodevPerDirectionOptions (optional)
options of the capture stream
out: AudiodevPerDirectionOptions (optional)
options of the playback stream
latency: int (optional)
add extra latency to playback in microseconds (default 10000)
Since
4.0
AudiodevJackPerDirectionOptions (Object)
Options of the JACK backend that are used for both playback and record-
ing.
Members
server-name: string (optional)
select from among several possible concurrent server instances
(default: environment variable $JACK_DEFAULT_SERVER if set, else
"default")
client-name: string (optional)
the client name to use. The server will modify this name to cre-
ate a unique variant, if needed unless exact-name is true (de-
fault: the guest's name)
connect-ports: string (optional)
if set, a regular expression of JACK client port name(s) to mon-
itor for and automatically connect to
start-server: boolean (optional)
start a jack server process if one is not already present (de-
fault: false)
exact-name: boolean (optional)
use the exact name requested otherwise JACK automatically gener-
ates a unique one, if needed (default: false)
The members of AudiodevPerDirectionOptions
Since
5.1
AudiodevJackOptions (Object)
Options of the JACK audio backend.
Members
in: AudiodevJackPerDirectionOptions (optional)
options of the capture stream
out: AudiodevJackPerDirectionOptions (optional)
options of the playback stream
Since
5.1
AudiodevOssPerDirectionOptions (Object)
Options of the OSS backend that are used for both playback and record-
ing.
Members
dev: string (optional)
file name of the OSS device (default '/dev/dsp')
buffer-count: int (optional)
number of buffers
try-poll: boolean (optional)
attempt to use poll mode, falling back to non-polling access on
failure (default true)
The members of AudiodevPerDirectionOptions
Since
4.0
AudiodevOssOptions (Object)
Options of the OSS audio backend.
Members
in: AudiodevOssPerDirectionOptions (optional)
options of the capture stream
out: AudiodevOssPerDirectionOptions (optional)
options of the playback stream
try-mmap: boolean (optional)
try using memory-mapped access, falling back to non-mem-
ory-mapped access on failure (default true)
exclusive: boolean (optional)
open device in exclusive mode (vmix won't work) (default false)
dsp-policy: int (optional)
set the timing policy of the device (between 0 and 10, where
smaller number means smaller latency but higher CPU usage) or -1
to use fragment mode (option ignored on some platforms) (default
5)
Since
4.0
AudiodevPaPerDirectionOptions (Object)
Options of the Pulseaudio backend that are used for both playback and
recording.
Members
name: string (optional)
name of the sink/source to use
stream-name: string (optional)
name of the PulseAudio stream created by qemu. Can be used to
identify the stream in PulseAudio when you create multiple
PulseAudio devices or run multiple qemu instances (default: au-
diodev's id, since 4.2)
latency: int (optional)
latency you want PulseAudio to achieve in microseconds (default
15000)
The members of AudiodevPerDirectionOptions
Since
4.0
AudiodevPaOptions (Object)
Options of the PulseAudio audio backend.
Members
in: AudiodevPaPerDirectionOptions (optional)
options of the capture stream
out: AudiodevPaPerDirectionOptions (optional)
options of the playback stream
server: string (optional)
PulseAudio server address (default: let PulseAudio choose)
Since
4.0
AudiodevSdlPerDirectionOptions (Object)
Options of the SDL audio backend that are used for both playback and
recording.
Members
buffer-count: int (optional)
number of buffers (default 4)
The members of AudiodevPerDirectionOptions
Since
6.0
AudiodevSdlOptions (Object)
Options of the SDL audio backend.
Members
in: AudiodevSdlPerDirectionOptions (optional)
options of the recording stream
out: AudiodevSdlPerDirectionOptions (optional)
options of the playback stream
Since
6.0
AudiodevWavOptions (Object)
Options of the wav audio backend.
Members
in: AudiodevPerDirectionOptions (optional)
options of the capture stream
out: AudiodevPerDirectionOptions (optional)
options of the playback stream
path: string (optional)
name of the wav file to record (default 'qemu.wav')
Since
4.0
AudioFormat (Enum)
An enumeration of possible audio formats.
Values
u8 unsigned 8 bit integer
s8 signed 8 bit integer
u16 unsigned 16 bit integer
s16 signed 16 bit integer
u32 unsigned 32 bit integer
s32 signed 32 bit integer
f32 single precision floating-point (since 5.0)
Since
4.0
AudiodevDriver (Enum)
An enumeration of possible audio backend drivers.
Values
jack JACK audio backend (since 5.1)
none Not documented
alsa Not documented
coreaudio
Not documented
dbus Not documented
dsound Not documented
oss Not documented
pa Not documented
sdl Not documented
sndio Not documented
spice Not documented
wav Not documented
Since
4.0
Audiodev (Object)
Options of an audio backend.
Members
id: string
identifier of the backend
driver: AudiodevDriver
the backend driver to use
timer-period: int (optional)
timer period (in microseconds, 0: use lowest possible)
The members of AudiodevGenericOptions when driver is "none"
The members of AudiodevAlsaOptions when driver is "alsa"
The members of AudiodevCoreaudioOptions when driver is "coreaudio"
The members of AudiodevGenericOptions when driver is "dbus"
The members of AudiodevDsoundOptions when driver is "dsound"
The members of AudiodevJackOptions when driver is "jack"
The members of AudiodevOssOptions when driver is "oss"
The members of AudiodevPaOptions when driver is "pa"
The members of AudiodevSdlOptions when driver is "sdl"
The members of AudiodevSndioOptions when driver is "sndio"
The members of AudiodevGenericOptions when driver is "spice"
The members of AudiodevWavOptions when driver is "wav"
Since
4.0
ACPI
AcpiTableOptions (Object)
Specify an ACPI table on the command line to load.
At most one of file and data can be specified. The list of files speci-
fied by any one of them is loaded and concatenated in order. If both
are omitted, data is implied.
Other fields / optargs can be used to override fields of the generic
ACPI table header; refer to the ACPI specification 5.0, section 5.2.6
System Description Table Header. If a header field is not overridden,
then the corresponding value from the concatenated blob is used (in
case of file), or it is filled in with a hard-coded value (in case of
data).
String fields are copied into the matching ACPI member from lowest ad-
dress upwards, and silently truncated / NUL-padded to length.
Members
sig: string (optional)
table signature / identifier (4 bytes)
rev: int (optional)
table revision number (dependent on signature, 1 byte)
oem_id: string (optional)
OEM identifier (6 bytes)
oem_table_id: string (optional)
OEM table identifier (8 bytes)
oem_rev: int (optional)
OEM-supplied revision number (4 bytes)
asl_compiler_id: string (optional)
identifier of the utility that created the table (4 bytes)
asl_compiler_rev: int (optional)
revision number of the utility that created the table (4 bytes)
file: string (optional)
colon (:) separated list of pathnames to load and concatenate as
table data. The resultant binary blob is expected to have an
ACPI table header. At least one file is required. This field ex-
cludes data.
data: string (optional)
colon (:) separated list of pathnames to load and concatenate as
table data. The resultant binary blob must not have an ACPI ta-
ble header. At least one file is required. This field excludes
file.
Since
1.5
ACPISlotType (Enum)
Values
DIMM memory slot
CPU logical CPU slot (since 2.7)
ACPIOSTInfo (Object)
OSPM Status Indication for a device For description of possible values
of source and status fields see "_OST (OSPM Status Indication)" chapter
of ACPI5.0 spec.
Members
device: string (optional)
device ID associated with slot
slot: string
slot ID, unique per slot of a given slot-type
slot-type: ACPISlotType
type of the slot
source: int
an integer containing the source event
status: int
an integer containing the status code
Since
2.1
query-acpi-ospm-status (Command)
Return a list of ACPIOSTInfo for devices that support status reporting
via ACPI _OST method.
Since
2.1
Example
-> { "execute": "query-acpi-ospm-status" }
<- { "return": [ { "device": "d1", "slot": "0", "slot-type": "DIMM", "source": 1, "status": 0},
{ "slot": "1", "slot-type": "DIMM", "source": 0, "status": 0},
{ "slot": "2", "slot-type": "DIMM", "source": 0, "status": 0},
{ "slot": "3", "slot-type": "DIMM", "source": 0, "status": 0}
]}
ACPI_DEVICE_OST (Event)
Emitted when guest executes ACPI _OST method.
Arguments
info: ACPIOSTInfo
OSPM Status Indication
Since
2.1
Example
<- { "event": "ACPI_DEVICE_OST",
"data": { "info": { "device": "d1", "slot": "0",
"slot-type": "DIMM", "source": 1, "status": 0 } },
"timestamp": { "seconds": 1265044230, "microseconds": 450486 } }
PCI
PciMemoryRange (Object)
A PCI device memory region
Members
base: int
the starting address (guest physical)
limit: int
the ending address (guest physical)
Since
0.14
PciMemoryRegion (Object)
Information about a PCI device I/O region.
Members
bar: int
the index of the Base Address Register for this region
type: string
• 'io' if the region is a PIO region
• 'memory' if the region is a MMIO region
size: int
memory size
prefetch: boolean (optional)
if type is 'memory', true if the memory is prefetchable
mem_type_64: boolean (optional)
if type is 'memory', true if the BAR is 64-bit
address: int
Not documented
Since
0.14
PciBusInfo (Object)
Information about a bus of a PCI Bridge device
Members
number: int
primary bus interface number. This should be the number of the
bus the device resides on.
secondary: int
secondary bus interface number. This is the number of the main
bus for the bridge
subordinate: int
This is the highest number bus that resides below the bridge.
io_range: PciMemoryRange
The PIO range for all devices on this bridge
memory_range: PciMemoryRange
The MMIO range for all devices on this bridge
prefetchable_range: PciMemoryRange
The range of prefetchable MMIO for all devices on this bridge
Since
2.4
PciBridgeInfo (Object)
Information about a PCI Bridge device
Members
bus: PciBusInfo
information about the bus the device resides on
devices: array of PciDeviceInfo (optional)
a list of PciDeviceInfo for each device on this bridge
Since
0.14
PciDeviceClass (Object)
Information about the Class of a PCI device
Members
desc: string (optional)
a string description of the device's class
class: int
the class code of the device
Since
2.4
PciDeviceId (Object)
Information about the Id of a PCI device
Members
device: int
the PCI device id
vendor: int
the PCI vendor id
subsystem: int (optional)
the PCI subsystem id (since 3.1)
subsystem-vendor: int (optional)
the PCI subsystem vendor id (since 3.1)
Since
2.4
PciDeviceInfo (Object)
Information about a PCI device
Members
bus: int
the bus number of the device
slot: int
the slot the device is located in
function: int
the function of the slot used by the device
class_info: PciDeviceClass
the class of the device
id: PciDeviceId
the PCI device id
irq: int (optional)
if an IRQ is assigned to the device, the IRQ number
irq_pin: int
the IRQ pin, zero means no IRQ (since 5.1)
qdev_id: string
the device name of the PCI device
pci_bridge: PciBridgeInfo (optional)
if the device is a PCI bridge, the bridge information
regions: array of PciMemoryRegion
a list of the PCI I/O regions associated with the device
Notes
the contents of class_info.desc are not stable and should only be
treated as informational.
Since
0.14
PciInfo (Object)
Information about a PCI bus
Members
bus: int
the bus index
devices: array of PciDeviceInfo
a list of devices on this bus
Since
0.14
query-pci (Command)
Return information about the PCI bus topology of the guest.
Returns
a list of PciInfo for each PCI bus. Each bus is represented by a
json-object, which has a key with a json-array of all PCI devices at-
tached to it. Each device is represented by a json-object.
Since
0.14
Example
-> { "execute": "query-pci" }
<- { "return": [
{
"bus": 0,
"devices": [
{
"bus": 0,
"qdev_id": "",
"slot": 0,
"class_info": {
"class": 1536,
"desc": "Host bridge"
},
"id": {
"device": 32902,
"vendor": 4663
},
"function": 0,
"regions": [
]
},
{
"bus": 0,
"qdev_id": "",
"slot": 1,
"class_info": {
"class": 1537,
"desc": "ISA bridge"
},
"id": {
"device": 32902,
"vendor": 28672
},
"function": 0,
"regions": [
]
},
{
"bus": 0,
"qdev_id": "",
"slot": 1,
"class_info": {
"class": 257,
"desc": "IDE controller"
},
"id": {
"device": 32902,
"vendor": 28688
},
"function": 1,
"regions": [
{
"bar": 4,
"size": 16,
"address": 49152,
"type": "io"
}
]
},
{
"bus": 0,
"qdev_id": "",
"slot": 2,
"class_info": {
"class": 768,
"desc": "VGA controller"
},
"id": {
"device": 4115,
"vendor": 184
},
"function": 0,
"regions": [
{
"prefetch": true,
"mem_type_64": false,
"bar": 0,
"size": 33554432,
"address": 4026531840,
"type": "memory"
},
{
"prefetch": false,
"mem_type_64": false,
"bar": 1,
"size": 4096,
"address": 4060086272,
"type": "memory"
},
{
"prefetch": false,
"mem_type_64": false,
"bar": 6,
"size": 65536,
"address": -1,
"type": "memory"
}
]
},
{
"bus": 0,
"qdev_id": "",
"irq": 11,
"slot": 4,
"class_info": {
"class": 1280,
"desc": "RAM controller"
},
"id": {
"device": 6900,
"vendor": 4098
},
"function": 0,
"regions": [
{
"bar": 0,
"size": 32,
"address": 49280,
"type": "io"
}
]
}
]
}
]
}
Note
This example has been shortened as the real response is too long.
STATISTICS
StatsType (Enum)
Enumeration of statistics types
Values
cumulative
stat is cumulative; value can only increase.
instant
stat is instantaneous; value can increase or decrease.
peak stat is the peak value; value can only increase.
linear-histogram
stat is a linear histogram.
log2-histogram
stat is a logarithmic histogram, with one bucket for each power
of two.
Since
7.1
StatsUnit (Enum)
Enumeration of unit of measurement for statistics
Values
bytes stat reported in bytes.
seconds
stat reported in seconds.
cycles stat reported in clock cycles.
boolean
stat is a boolean value.
Since
7.1
StatsProvider (Enum)
Enumeration of statistics providers.
Values
kvm Not documented
Since
7.1
StatsTarget (Enum)
The kinds of objects on which one can request statistics.
Values
vm statistics that apply to the entire virtual machine or the en-
tire QEMU process.
vcpu statistics that apply to a single virtual CPU.
Since
7.1
StatsRequest (Object)
Indicates a set of statistics that should be returned by query-stats.
Members
provider: StatsProvider
provider for which to return statistics.
names: array of string (optional)
statistics to be returned (all if omitted).
Since
7.1
StatsVCPUFilter (Object)
Members
vcpus: array of string (optional)
list of QOM paths for the desired vCPU objects.
Since
7.1
StatsFilter (Object)
The arguments to the query-stats command; specifies a target for which
to request statistics and optionally the required subset of information
for that target: - which vCPUs to request statistics for - which
providers to request statistics from - which named values to return
within each provider
Members
target: StatsTarget
Not documented
providers: array of StatsRequest (optional)
Not documented
The members of StatsVCPUFilter when target is "vcpu"
Since
7.1
StatsValue (Alternate)
Members
scalar: int
single unsigned 64-bit integers.
list: array of int
list of unsigned 64-bit integers (used for histograms).
boolean: boolean
Not documented
Since
7.1
Stats (Object)
Members
name: string
name of stat.
value: StatsValue
stat value.
Since
7.1
StatsResult (Object)
Members
provider: StatsProvider
provider for this set of statistics.
qom-path: string (optional)
Path to the object for which the statistics are returned, if the
object is exposed in the QOM tree
stats: array of Stats
list of statistics.
Since
7.1
query-stats (Command)
Return runtime-collected statistics for objects such as the VM or its
vCPUs.
The arguments are a StatsFilter and specify the provider and objects to
return statistics about.
Arguments
The members of StatsFilter
Returns
a list of StatsResult, one for each provider and object (e.g., for each
vCPU).
Since
7.1
StatsSchemaValue (Object)
Schema for a single statistic.
Members
name: string
name of the statistic; each element of the schema is uniquely
identified by a target, a provider (both available in StatsS-
chema) and the name.
type: StatsType
kind of statistic.
unit: StatsUnit (optional)
basic unit of measure for the statistic; if missing, the statis-
tic is a simple number or counter.
base: int (optional)
base for the multiple of unit in which the statistic is mea-
sured. Only present if exponent is non-zero; base and exponent
together form a SI prefix (e.g., _nano-_ for base=10 and expo-
nent=-9) or IEC binary prefix (e.g. _kibi-_ for base=2 and expo-
nent=10)
exponent: int
exponent for the multiple of unit in which the statistic is ex-
pressed, or 0 for the basic unit
bucket-size: int (optional)
Present when type is "linear-histogram", contains the width of
each bucket of the histogram.
Since
7.1
StatsSchema (Object)
Schema for all available statistics for a provider and target.
Members
provider: StatsProvider
provider for this set of statistics.
target: StatsTarget
the kind of object that can be queried through the provider.
stats: array of StatsSchemaValue
list of statistics.
Since
7.1
query-stats-schemas (Command)
Return the schema for all available runtime-collected statistics.
Arguments
provider: StatsProvider (optional)
Not documented
Note
runtime-collected statistics and their names fall outside QEMU's usual
deprecation policies. QEMU will try to keep the set of available data
stable, together with their names, but will not guarantee stability at
all costs; the same is true of providers that source statistics exter-
nally, e.g. from Linux. For example, if the same value is being
tracked with different names on different architectures or by different
providers, one of them might be renamed. A statistic might go away if
an algorithm is changed or some code is removed; changing a default
might cause previously useful statistics to always report 0. Such
changes, however, are expected to be rare.
Since
7.1
VIRTIO DEVICES
VirtioInfo (Object)
Basic information about a given VirtIODevice
Members
path: string
The VirtIODevice's canonical QOM path
name: string
Name of the VirtIODevice
Since
7.2
x-query-virtio (Command)
Returns a list of all realized VirtIODevices
Features
unstable
This command is meant for debugging.
Returns
List of gathered VirtIODevices
Since
7.2
Example
-> { "execute": "x-query-virtio" }
<- { "return": [
{
"name": "virtio-input",
"path": "/machine/peripheral-anon/device[4]/virtio-backend"
},
{
"name": "virtio-crypto",
"path": "/machine/peripheral/crypto0/virtio-backend"
},
{
"name": "virtio-scsi",
"path": "/machine/peripheral-anon/device[2]/virtio-backend"
},
{
"name": "virtio-net",
"path": "/machine/peripheral-anon/device[1]/virtio-backend"
},
{
"name": "virtio-serial",
"path": "/machine/peripheral-anon/device[0]/virtio-backend"
}
]
}
VhostStatus (Object)
Information about a vhost device. This information will only be dis-
played if the vhost device is active.
Members
n-mem-sections: int
vhost_dev n_mem_sections
n-tmp-sections: int
vhost_dev n_tmp_sections
nvqs: int
vhost_dev nvqs (number of virtqueues being used)
vq-index: int
vhost_dev vq_index
features: VirtioDeviceFeatures
vhost_dev features
acked-features: VirtioDeviceFeatures
vhost_dev acked_features
backend-features: VirtioDeviceFeatures
vhost_dev backend_features
protocol-features: VhostDeviceProtocols
vhost_dev protocol_features
max-queues: int
vhost_dev max_queues
backend-cap: int
vhost_dev backend_cap
log-enabled: boolean
vhost_dev log_enabled flag
log-size: int
vhost_dev log_size
Since
7.2
VirtioStatus (Object)
Full status of the virtio device with most VirtIODevice members. Also
includes the full status of the corresponding vhost device if the vhost
device is active.
Members
name: string
VirtIODevice name
device-id: int
VirtIODevice ID
vhost-started: boolean
VirtIODevice vhost_started flag
guest-features: VirtioDeviceFeatures
VirtIODevice guest_features
host-features: VirtioDeviceFeatures
VirtIODevice host_features
backend-features: VirtioDeviceFeatures
VirtIODevice backend_features
device-endian: string
VirtIODevice device_endian
num-vqs: int
VirtIODevice virtqueue count. This is the number of active
virtqueues being used by the VirtIODevice.
status: VirtioDeviceStatus
VirtIODevice configuration status (VirtioDeviceStatus)
isr: int
VirtIODevice ISR
queue-sel: int
VirtIODevice queue_sel
vm-running: boolean
VirtIODevice vm_running flag
broken: boolean
VirtIODevice broken flag
disabled: boolean
VirtIODevice disabled flag
use-started: boolean
VirtIODevice use_started flag
started: boolean
VirtIODevice started flag
start-on-kick: boolean
VirtIODevice start_on_kick flag
disable-legacy-check: boolean
VirtIODevice disabled_legacy_check flag
bus-name: string
VirtIODevice bus_name
use-guest-notifier-mask: boolean
VirtIODevice use_guest_notifier_mask flag
vhost-dev: VhostStatus (optional)
Corresponding vhost device info for a given VirtIODevice.
Present if the given VirtIODevice has an active vhost device.
Since
7.2
x-query-virtio-status (Command)
Poll for a comprehensive status of a given virtio device
Arguments
path: string
Canonical QOM path of the VirtIODevice
Features
unstable
This command is meant for debugging.
Returns
VirtioStatus of the virtio device
Since
7.2
Examples
1. Poll for the status of virtio-crypto (no vhost-crypto active)
-> { "execute": "x-query-virtio-status",
"arguments": { "path": "/machine/peripheral/crypto0/virtio-backend" }
}
<- { "return": {
"device-endian": "little",
"bus-name": "",
"disable-legacy-check": false,
"name": "virtio-crypto",
"started": true,
"device-id": 20,
"backend-features": {
"transports": [],
"dev-features": []
},
"start-on-kick": false,
"isr": 1,
"broken": false,
"status": {
"statuses": [
"VIRTIO_CONFIG_S_ACKNOWLEDGE: Valid virtio device found",
"VIRTIO_CONFIG_S_DRIVER: Guest OS compatible with device",
"VIRTIO_CONFIG_S_FEATURES_OK: Feature negotiation complete",
"VIRTIO_CONFIG_S_DRIVER_OK: Driver setup and ready"
]
},
"num-vqs": 2,
"guest-features": {
"dev-features": [],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)"
]
},
"host-features": {
"unknown-dev-features": 1073741824,
"dev-features": [],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)",
"VIRTIO_F_ANY_LAYOUT: Device accepts arbitrary desc. layouts",
"VIRTIO_F_NOTIFY_ON_EMPTY: Notify when device runs out of avail. descs. on VQ"
]
},
"use-guest-notifier-mask": true,
"vm-running": true,
"queue-sel": 1,
"disabled": false,
"vhost-started": false,
"use-started": true
}
}
2. Poll for the status of virtio-net (vhost-net is active)
-> { "execute": "x-query-virtio-status",
"arguments": { "path": "/machine/peripheral-anon/device[1]/virtio-backend" }
}
<- { "return": {
"device-endian": "little",
"bus-name": "",
"disabled-legacy-check": false,
"name": "virtio-net",
"started": true,
"device-id": 1,
"vhost-dev": {
"n-tmp-sections": 4,
"n-mem-sections": 4,
"max-queues": 1,
"backend-cap": 2,
"log-size": 0,
"backend-features": {
"dev-features": [],
"transports": []
},
"nvqs": 2,
"protocol-features": {
"protocols": []
},
"vq-index": 0,
"log-enabled": false,
"acked-features": {
"dev-features": [
"VIRTIO_NET_F_MRG_RXBUF: Driver can merge receive buffers"
],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)"
]
},
"features": {
"dev-features": [
"VHOST_F_LOG_ALL: Logging write descriptors supported",
"VIRTIO_NET_F_MRG_RXBUF: Driver can merge receive buffers"
],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_IOMMU_PLATFORM: Device can be used on IOMMU platform",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)",
"VIRTIO_F_ANY_LAYOUT: Device accepts arbitrary desc. layouts",
"VIRTIO_F_NOTIFY_ON_EMPTY: Notify when device runs out of avail. descs. on VQ"
]
}
},
"backend-features": {
"dev-features": [
"VHOST_USER_F_PROTOCOL_FEATURES: Vhost-user protocol features negotiation supported",
"VIRTIO_NET_F_GSO: Handling GSO-type packets supported",
"VIRTIO_NET_F_CTRL_MAC_ADDR: MAC address set through control channel",
"VIRTIO_NET_F_GUEST_ANNOUNCE: Driver sending gratuitous packets supported",
"VIRTIO_NET_F_CTRL_RX_EXTRA: Extra RX mode control supported",
"VIRTIO_NET_F_CTRL_VLAN: Control channel VLAN filtering supported",
"VIRTIO_NET_F_CTRL_RX: Control channel RX mode supported",
"VIRTIO_NET_F_CTRL_VQ: Control channel available",
"VIRTIO_NET_F_STATUS: Configuration status field available",
"VIRTIO_NET_F_MRG_RXBUF: Driver can merge receive buffers",
"VIRTIO_NET_F_HOST_UFO: Device can receive UFO",
"VIRTIO_NET_F_HOST_ECN: Device can receive TSO with ECN",
"VIRTIO_NET_F_HOST_TSO6: Device can receive TSOv6",
"VIRTIO_NET_F_HOST_TSO4: Device can receive TSOv4",
"VIRTIO_NET_F_GUEST_UFO: Driver can receive UFO",
"VIRTIO_NET_F_GUEST_ECN: Driver can receive TSO with ECN",
"VIRTIO_NET_F_GUEST_TSO6: Driver can receive TSOv6",
"VIRTIO_NET_F_GUEST_TSO4: Driver can receive TSOv4",
"VIRTIO_NET_F_MAC: Device has given MAC address",
"VIRTIO_NET_F_CTRL_GUEST_OFFLOADS: Control channel offloading reconfig. supported",
"VIRTIO_NET_F_GUEST_CSUM: Driver handling packets with partial checksum supported",
"VIRTIO_NET_F_CSUM: Device handling packets with partial checksum supported"
],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)",
"VIRTIO_F_ANY_LAYOUT: Device accepts arbitrary desc. layouts",
"VIRTIO_F_NOTIFY_ON_EMPTY: Notify when device runs out of avail. descs. on VQ"
]
},
"start-on-kick": false,
"isr": 1,
"broken": false,
"status": {
"statuses": [
"VIRTIO_CONFIG_S_ACKNOWLEDGE: Valid virtio device found",
"VIRTIO_CONFIG_S_DRIVER: Guest OS compatible with device",
"VIRTIO_CONFIG_S_FEATURES_OK: Feature negotiation complete",
"VIRTIO_CONFIG_S_DRIVER_OK: Driver setup and ready"
]
},
"num-vqs": 3,
"guest-features": {
"dev-features": [
"VIRTIO_NET_F_CTRL_MAC_ADDR: MAC address set through control channel",
"VIRTIO_NET_F_GUEST_ANNOUNCE: Driver sending gratuitous packets supported",
"VIRTIO_NET_F_CTRL_VLAN: Control channel VLAN filtering supported",
"VIRTIO_NET_F_CTRL_RX: Control channel RX mode supported",
"VIRTIO_NET_F_CTRL_VQ: Control channel available",
"VIRTIO_NET_F_STATUS: Configuration status field available",
"VIRTIO_NET_F_MRG_RXBUF: Driver can merge receive buffers",
"VIRTIO_NET_F_HOST_UFO: Device can receive UFO",
"VIRTIO_NET_F_HOST_ECN: Device can receive TSO with ECN",
"VIRTIO_NET_F_HOST_TSO6: Device can receive TSOv6",
"VIRTIO_NET_F_HOST_TSO4: Device can receive TSOv4",
"VIRTIO_NET_F_GUEST_UFO: Driver can receive UFO",
"VIRTIO_NET_F_GUEST_ECN: Driver can receive TSO with ECN",
"VIRTIO_NET_F_GUEST_TSO6: Driver can receive TSOv6",
"VIRTIO_NET_F_GUEST_TSO4: Driver can receive TSOv4",
"VIRTIO_NET_F_MAC: Device has given MAC address",
"VIRTIO_NET_F_CTRL_GUEST_OFFLOADS: Control channel offloading reconfig. supported",
"VIRTIO_NET_F_GUEST_CSUM: Driver handling packets with partial checksum supported",
"VIRTIO_NET_F_CSUM: Device handling packets with partial checksum supported"
],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)"
]
},
"host-features": {
"dev-features": [
"VHOST_USER_F_PROTOCOL_FEATURES: Vhost-user protocol features negotiation supported",
"VIRTIO_NET_F_GSO: Handling GSO-type packets supported",
"VIRTIO_NET_F_CTRL_MAC_ADDR: MAC address set through control channel",
"VIRTIO_NET_F_GUEST_ANNOUNCE: Driver sending gratuitous packets supported",
"VIRTIO_NET_F_CTRL_RX_EXTRA: Extra RX mode control supported",
"VIRTIO_NET_F_CTRL_VLAN: Control channel VLAN filtering supported",
"VIRTIO_NET_F_CTRL_RX: Control channel RX mode supported",
"VIRTIO_NET_F_CTRL_VQ: Control channel available",
"VIRTIO_NET_F_STATUS: Configuration status field available",
"VIRTIO_NET_F_MRG_RXBUF: Driver can merge receive buffers",
"VIRTIO_NET_F_HOST_UFO: Device can receive UFO",
"VIRTIO_NET_F_HOST_ECN: Device can receive TSO with ECN",
"VIRTIO_NET_F_HOST_TSO6: Device can receive TSOv6",
"VIRTIO_NET_F_HOST_TSO4: Device can receive TSOv4",
"VIRTIO_NET_F_GUEST_UFO: Driver can receive UFO",
"VIRTIO_NET_F_GUEST_ECN: Driver can receive TSO with ECN",
"VIRTIO_NET_F_GUEST_TSO6: Driver can receive TSOv6",
"VIRTIO_NET_F_GUEST_TSO4: Driver can receive TSOv4",
"VIRTIO_NET_F_MAC: Device has given MAC address",
"VIRTIO_NET_F_CTRL_GUEST_OFFLOADS: Control channel offloading reconfig. supported",
"VIRTIO_NET_F_GUEST_CSUM: Driver handling packets with partial checksum supported",
"VIRTIO_NET_F_CSUM: Device handling packets with partial checksum supported"
],
"transports": [
"VIRTIO_RING_F_EVENT_IDX: Used & avail. event fields enabled",
"VIRTIO_RING_F_INDIRECT_DESC: Indirect descriptors supported",
"VIRTIO_F_VERSION_1: Device compliant for v1 spec (legacy)",
"VIRTIO_F_ANY_LAYOUT: Device accepts arbitrary desc. layouts",
"VIRTIO_F_NOTIFY_ON_EMPTY: Notify when device runs out of avail. descs. on VQ"
]
},
"use-guest-notifier-mask": true,
"vm-running": true,
"queue-sel": 2,
"disabled": false,
"vhost-started": true,
"use-started": true
}
}
VirtioDeviceStatus (Object)
A structure defined to list the configuration statuses of a virtio de-
vice
Members
statuses: array of string
List of decoded configuration statuses of the virtio device
unknown-statuses: int (optional)
Virtio device statuses bitmap that have not been decoded
Since
7.2
VhostDeviceProtocols (Object)
A structure defined to list the vhost user protocol features of a Vhost
User device
Members
protocols: array of string
List of decoded vhost user protocol features of a vhost user de-
vice
unknown-protocols: int (optional)
Vhost user device protocol features bitmap that have not been
decoded
Since
7.2
VirtioDeviceFeatures (Object)
The common fields that apply to most Virtio devices. Some devices may
not have their own device-specific features (e.g. virtio-rng).
Members
transports: array of string
List of transport features of the virtio device
dev-features: array of string (optional)
List of device-specific features (if the device has unique fea-
tures)
unknown-dev-features: int (optional)
Virtio device features bitmap that have not been decoded
Since
7.2
VirtQueueStatus (Object)
Information of a VirtIODevice VirtQueue, including most members of the
VirtQueue data structure.
Members
name: string
Name of the VirtIODevice that uses this VirtQueue
queue-index: int
VirtQueue queue_index
inuse: int
VirtQueue inuse
vring-num: int
VirtQueue vring.num
vring-num-default: int
VirtQueue vring.num_default
vring-align: int
VirtQueue vring.align
vring-desc: int
VirtQueue vring.desc (descriptor area)
vring-avail: int
VirtQueue vring.avail (driver area)
vring-used: int
VirtQueue vring.used (device area)
last-avail-idx: int (optional)
VirtQueue last_avail_idx or return of vhost_dev
vhost_get_vring_base (if vhost active)
shadow-avail-idx: int (optional)
VirtQueue shadow_avail_idx
used-idx: int
VirtQueue used_idx
signalled-used: int
VirtQueue signalled_used
signalled-used-valid: boolean
VirtQueue signalled_used_valid flag
Since
7.2
x-query-virtio-queue-status (Command)
Return the status of a given VirtIODevice's VirtQueue
Arguments
path: string
VirtIODevice canonical QOM path
queue: int
VirtQueue index to examine
Features
unstable
This command is meant for debugging.
Returns
VirtQueueStatus of the VirtQueue
Notes
last_avail_idx will not be displayed in the case where the selected
VirtIODevice has a running vhost device and the VirtIODevice VirtQueue
index (queue) does not exist for the corresponding vhost device
vhost_virtqueue. Also, shadow_avail_idx will not be displayed in the
case where the selected VirtIODevice has a running vhost device.
Since
7.2
Examples
1. Get VirtQueueStatus for virtio-vsock (vhost-vsock running)
-> { "execute": "x-query-virtio-queue-status",
"arguments": { "path": "/machine/peripheral/vsock0/virtio-backend",
"queue": 1 }
}
<- { "return": {
"signalled-used": 0,
"inuse": 0,
"name": "vhost-vsock",
"vring-align": 4096,
"vring-desc": 5217370112,
"signalled-used-valid": false,
"vring-num-default": 128,
"vring-avail": 5217372160,
"queue-index": 1,
"last-avail-idx": 0,
"vring-used": 5217372480,
"used-idx": 0,
"vring-num": 128
}
}
2. Get VirtQueueStatus for virtio-serial (no vhost)
-> { "execute": "x-query-virtio-queue-status",
"arguments": { "path": "/machine/peripheral-anon/device[0]/virtio-backend",
"queue": 20 }
}
<- { "return": {
"signalled-used": 0,
"inuse": 0,
"name": "virtio-serial",
"vring-align": 4096,
"vring-desc": 5182074880,
"signalled-used-valid": false,
"vring-num-default": 128,
"vring-avail": 5182076928,
"queue-index": 20,
"last-avail-idx": 0,
"vring-used": 5182077248,
"used-idx": 0,
"shadow-avail-idx": 0,
"vring-num": 128
}
}
VirtVhostQueueStatus (Object)
Information of a vhost device's vhost_virtqueue, including most members
of the vhost_dev vhost_virtqueue data structure.
Members
name: string
Name of the VirtIODevice that uses this vhost_virtqueue
kick: int
vhost_virtqueue kick
call: int
vhost_virtqueue call
desc: int
vhost_virtqueue desc
avail: int
vhost_virtqueue avail
used: int
vhost_virtqueue used
num: int
vhost_virtqueue num
desc-phys: int
vhost_virtqueue desc_phys (descriptor area phys. addr.)
desc-size: int
vhost_virtqueue desc_size
avail-phys: int
vhost_virtqueue avail_phys (driver area phys. addr.)
avail-size: int
vhost_virtqueue avail_size
used-phys: int
vhost_virtqueue used_phys (device area phys. addr.)
used-size: int
vhost_virtqueue used_size
Since
7.2
x-query-virtio-vhost-queue-status (Command)
Return information of a given vhost device's vhost_virtqueue
Arguments
path: string
VirtIODevice canonical QOM path
queue: int
vhost_virtqueue index to examine
Features
unstable
This command is meant for debugging.
Returns
VirtVhostQueueStatus of the vhost_virtqueue
Since
7.2
Examples
1. Get vhost_virtqueue status for vhost-crypto
-> { "execute": "x-query-virtio-vhost-queue-status",
"arguments": { "path": "/machine/peripheral/crypto0/virtio-backend",
"queue": 0 }
}
<- { "return": {
"avail-phys": 5216124928,
"name": "virtio-crypto",
"used-phys": 5216127040,
"avail-size": 2054,
"desc-size": 16384,
"used-size": 8198,
"desc": 140141447430144,
"num": 1024,
"call": 0,
"avail": 140141447446528,
"desc-phys": 5216108544,
"used": 140141447448640,
"kick": 0
}
}
2. Get vhost_virtqueue status for vhost-vsock
-> { "execute": "x-query-virtio-vhost-queue-status",
"arguments": { "path": "/machine/peripheral/vsock0/virtio-backend",
"queue": 0 }
}
<- { "return": {
"avail-phys": 5182261248,
"name": "vhost-vsock",
"used-phys": 5182261568,
"avail-size": 262,
"desc-size": 2048,
"used-size": 1030,
"desc": 140141413580800,
"num": 128,
"call": 0,
"avail": 140141413582848,
"desc-phys": 5182259200,
"used": 140141413583168,
"kick": 0
}
}
VirtioRingDesc (Object)
Information regarding the vring descriptor area
Members
addr: int
Guest physical address of the descriptor area
len: int
Length of the descriptor area
flags: array of string
List of descriptor flags
Since
7.2
VirtioRingAvail (Object)
Information regarding the avail vring (a.k.a. driver area)
Members
flags: int
VRingAvail flags
idx: int
VRingAvail index
ring: int
VRingAvail ring[] entry at provided index
Since
7.2
VirtioRingUsed (Object)
Information regarding the used vring (a.k.a. device area)
Members
flags: int
VRingUsed flags
idx: int
VRingUsed index
Since
7.2
VirtioQueueElement (Object)
Information regarding a VirtQueue's VirtQueueElement including descrip-
tor, driver, and device areas
Members
name: string
Name of the VirtIODevice that uses this VirtQueue
index: int
Index of the element in the queue
descs: array of VirtioRingDesc
List of descriptors (VirtioRingDesc)
avail: VirtioRingAvail
VRingAvail info
used: VirtioRingUsed
VRingUsed info
Since
7.2
x-query-virtio-queue-element (Command)
Return the information about a VirtQueue's VirtQueueElement
Arguments
path: string
VirtIODevice canonical QOM path
queue: int
VirtQueue index to examine
index: int (optional)
Index of the element in the queue (default: head of the queue)
Features
unstable
This command is meant for debugging.
Returns
VirtioQueueElement information
Since
7.2
Examples
1. Introspect on virtio-net's VirtQueue 0 at index 5
-> { "execute": "x-query-virtio-queue-element",
"arguments": { "path": "/machine/peripheral-anon/device[1]/virtio-backend",
"queue": 0,
"index": 5 }
}
<- { "return": {
"index": 5,
"name": "virtio-net",
"descs": [
{
"flags": ["write"],
"len": 1536,
"addr": 5257305600
}
],
"avail": {
"idx": 256,
"flags": 0,
"ring": 5
},
"used": {
"idx": 13,
"flags": 0
}
}
}
2. Introspect on virtio-crypto's VirtQueue 1 at head
-> { "execute": "x-query-virtio-queue-element",
"arguments": { "path": "/machine/peripheral/crypto0/virtio-backend",
"queue": 1 }
}
<- { "return": {
"index": 0,
"name": "virtio-crypto",
"descs": [
{
"flags": [],
"len": 0,
"addr": 8080268923184214134
}
],
"avail": {
"idx": 280,
"flags": 0,
"ring": 0
},
"used": {
"idx": 280,
"flags": 0
}
}
}
3. Introspect on virtio-scsi's VirtQueue 2 at head
-> { "execute": "x-query-virtio-queue-element",
"arguments": { "path": "/machine/peripheral-anon/device[2]/virtio-backend",
"queue": 2 }
}
<- { "return": {
"index": 19,
"name": "virtio-scsi",
"descs": [
{
"flags": ["used", "indirect", "write"],
"len": 4099327944,
"addr": 12055409292258155293
}
],
"avail": {
"idx": 1147,
"flags": 0,
"ring": 19
},
"used": {
"idx": 280,
"flags": 0
}
}
}
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2024, The QEMU Project Developers
7.2.11 May 09, 2024 QEMU-QMP-REF(7)
Generated by dwww version 1.15 on Thu Jun 27 16:23:13 CEST 2024.