qemu-storage-daemon-qmp-ref - Man Page

• QEMU Storage Daemon QMP Reference Manual

  • Common data types

    • IoOperationType (Enum)
    • OnOffAuto (Enum)
    • OnOffSplit (Enum)
    • 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)
    • FdSocketAddress (Object)
    • InetSocketAddressWrapper (Object)
    • UnixSocketAddressWrapper (Object)
    • VsockSocketAddressWrapper (Object)
    • FdSocketAddressWrapper (Object)
    • SocketAddressLegacy (Object)
    • SocketAddressType (Enum)
    • SocketAddress (Object)

  • Cryptography

    • QCryptoTLSCredsEndpoint (Enum)
    • QCryptoSecretFormat (Enum)
    • QCryptoHashAlgo (Enum)
    • QCryptoCipherAlgo (Enum)
    • QCryptoCipherMode (Enum)
    • QCryptoIVGenAlgo (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)
    • QCryptoAkCipherAlgo (Enum)
    • QCryptoAkCipherKeyType (Enum)
    • QCryptoRSAPaddingAlgo (Enum)
    • QCryptoAkCipherOptionsRSA (Object)
    • QCryptoAkCipherOptions (Object)

  • Background jobs

    • JobType (Enum)
    • JobStatus (Enum)
    • JobVerb (Enum)
    • JOB_STATUS_CHANGE (Event)
    • job-pause (Command)
    • job-resume (Command)
    • job-cancel (Command)
    • job-complete (Command)
    • job-dismiss (Command)
    • job-finalize (Command)
    • JobInfo (Object)
    • query-jobs (Command)

  • Block devices

    • Block core (VM unrelated)
    • 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)
    • ChardevPty (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)
    • ChardevPtyWrapper (Object)
    • ChardevBackend (Object)
    • ChardevReturn (Object)
    • chardev-add (Command)
    • chardev-change (Command)
    • chardev-remove (Command)
    • chardev-send-break (Command)
    • VSERPORT_CHANGE (Event)

  • User authorization

    • QAuthZListPolicy (Enum)
    • QAuthZListFormat (Enum)
    • QAuthZListRule (Object)
    • AuthZListProperties (Object)
    • AuthZListFileProperties (Object)
    • AuthZPAMProperties (Object)
    • AuthZSimpleProperties (Object)

  • 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)

  • 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)
    • MemoryBackendShmProperties (Object)
    • MemoryBackendEpcProperties (Object)
    • PrManagerHelperProperties (Object)
    • QtestProperties (Object)
    • RemoteObjectProperties (Object)
    • VfioUserServerProperties (Object)
    • IOMMUFDProperties (Object)
    • AcpiGenericInitiatorProperties (Object)
    • AcpiGenericPortProperties (Object)
    • RngProperties (Object)
    • RngEgdProperties (Object)
    • RngRandomProperties (Object)
    • SevCommonProperties (Object)
    • SevGuestProperties (Object)
    • SevSnpGuestProperties (Object)
    • ThreadContextProperties (Object)
    • ObjectType (Enum)
    • ObjectOptions (Object)
    • object-add (Command)
    • object-del (Command)

An enumeration of the I/O operation types

read

read operation

write

write operation

2.1

An enumeration of three options: on, off, and auto

auto

QEMU selects the value between on and off

on

Enabled

off

Disabled

2.2

An enumeration of three values: on, off, and split

on

Enabled

off

Disabled

split

Mixed

2.6

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 different meaning.

s: string

the string value

n: null

no string value

2.10

An enumeration of options for specifying a PCI BAR

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

2.12

An enumeration of PCIe link speeds in units of GT/s

2_5

2.5GT/s

5

5.0GT/s

8

8.0GT/s

16

16.0GT/s

32

32.0GT/s (since 9.0)

64

64.0GT/s (since 9.0)

4.0

An enumeration of PCIe link width

1

x1

2

x2

4

x4

8

x8

12

x12

16

x16

32

x32

4.0

Host memory policy types

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

2.1

Indicates whether a netfilter is attached to a netdev's transmit queue or receive queue or both.

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.

2.5

Key combinations to toggle input-linux between host and guest.

ctrl-ctrl

left and right control key

alt-alt

left and right alt key

shift-shift

left and right shift key

meta-meta

left and right meta key

scrolllock

scroll lock key

ctrl-scrolllock

either control key and scroll lock key

4.0

human-readable-text: string

Formatted output intended for humans.

6.2

The network address family

ipv4

IPV4 family

ipv6

IPV6 family

unix

unix socket

vsock

vsock family (since 2.8)

unknown

otherwise

2.1

host: string

host part of the address

port: string

port part of the address

Captures a socket address or address range in the Internet namespace.

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 between 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

1.3

Captures a socket address in the local ("Unix socket") namespace.

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)

1.3

Captures a socket address in the vsock namespace.

cid: string

unique host identifier

port: string

port

NOTE:

String types are used to allow for possible future hostname or service resolution support.

2.8

A file descriptor name or number.

str: string

decimal is for file descriptor number, otherwise it's a file descriptor name.  Named file descriptors are permitted in monitor commands, in combination with the 'getfd' command. Decimal file descriptors are permitted at startup or other contexts where no monitor context is active.

1.2

data: InetSocketAddress

internet domain socket address

1.3

data: UnixSocketAddress

UNIX domain socket address

1.3

data: VsockSocketAddress

VSOCK domain socket address

2.8

data: FdSocketAddress

file descriptor name or number

1.3

Captures the address of a socket, which could also be a named file descriptor

type: SocketAddressType

Transport type

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 FdSocketAddressWrapper when type is "fd"

1.3

Available SocketAddress types

inet

Internet address

unix

Unix domain socket

vsock

VMCI address

fd

Socket file descriptor

2.9

Captures the address of a socket, which could also be a socket file descriptor

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 FdSocketAddress when type is "fd"

2.9

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.

client

the network endpoint is acting as the client

server

the network endpoint is acting as the server

2.5

The data format that the secret is provided in

raw

raw bytes.  When encoded in JSON only valid UTF-8 sequences can be used

base64

arbitrary base64 encoded binary data

2.6

The supported algorithms for computing content digests

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)

sm3

SM3. (since 9.2.0)

2.6

The supported algorithms for content encryption ciphers

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

sm4

SM4 with 128 bit / 16 byte keys (since 9.0)

2.6

The supported modes for content encryption ciphers

ecb

Electronic Code Book

cbc

Cipher Block Chaining

xts

XEX with tweaked code book and ciphertext stealing

ctr

Counter (Since 2.8)

2.6

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.

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

2.6

The supported full disk encryption formats

qcow

QCow/QCow2 built-in AES-CBC encryption.  Use only for liberating data from old images.

luks

LUKS encryption format.  Recommended for new images

2.6

The common options that apply to all full disk encryption formats

format: QCryptoBlockFormat

the encryption format

2.6

The options that apply to QCow/QCow2 AES-CBC encryption format

key-secret: string (optional)

the ID of a QCryptoSecret object providing the decryption key.  Mandatory except when probing image for metadata only.

2.6

The options that apply to LUKS encryption format

key-secret: string (optional)

the ID of a QCryptoSecret object providing the decryption key.  Mandatory except when probing image for metadata only.

2.6

The options that apply to LUKS encryption format initialization

cipher-alg: QCryptoCipherAlgo (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: QCryptoIVGenAlgo (optional)

the initialization vector generator Currently defaults to 'plain64'

ivgen-hash-alg: QCryptoHashAlgo (optional)

the initialization vector generator hash Currently defaults to 'sha256'

hash-alg: QCryptoHashAlgo (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

2.6

The options that are available for all encryption formats when opening an existing volume

The members of QCryptoBlockOptionsBase

The members of QCryptoBlockOptionsQCow when format is "qcow"

The members of QCryptoBlockOptionsLUKS when format is "luks"

2.6

The options that are available for all encryption formats when initializing a new volume

The members of QCryptoBlockOptionsBase

The members of QCryptoBlockOptionsQCow when format is "qcow"

The members of QCryptoBlockCreateOptionsLUKS when format is "luks"

2.6

The common information that applies to all full disk encryption formats

format: QCryptoBlockFormat

the encryption format

2.7

Information about the LUKS block encryption key slot options

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

2.7

Information about the LUKS block encryption options

cipher-alg: QCryptoCipherAlgo

the cipher algorithm for data encryption

cipher-mode: QCryptoCipherMode

the cipher mode for data encryption

ivgen-alg: QCryptoIVGenAlgo

the initialization vector generator

ivgen-hash-alg: QCryptoHashAlgo (optional)

the initialization vector generator hash

hash-alg: QCryptoHashAlgo

the master key hash algorithm

detached-header: boolean

whether the LUKS header is detached (Since 9.0)

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

2.7

Information about the block encryption options

The members of QCryptoBlockInfoBase

The members of QCryptoBlockInfoLUKS when format is "luks"

2.7

Defines state of keyslots that are affected by the update

active

The slots contain the given password and marked as active

inactive

The slots are erased (contain garbage) and marked as inactive

5.1

This struct defines the update parameters that activate/de-activate set of keyslots

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 password to use to retrieve current master key.  Defaults to the same secret that was used to open the image

5.1

The options that are available for all encryption formats when amending encryption settings

The members of QCryptoBlockOptionsBase

The members of QCryptoBlockAmendOptionsLUKS when format is "luks"

5.1

Properties for objects of classes derived from secret-common.

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 unencrypted.

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 absent.

2.6

Properties for secret objects.

Either data or file must be provided, but not both.

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

2.6

Properties for secret_keyring objects.

serial: int

serial number that identifies a key to get from the kernel

The members of SecretCommonProperties

5.1

CONFIG_SECRET_KEYRING

Properties for objects of classes derived from tls-creds.

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.  (default: 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

2.5

Properties for tls-creds-anon objects.

The members of TlsCredsProperties

2.5

Properties for tls-creds-psk objects.

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

3.0

Properties for tls-creds-x509 objects.

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 version by providing the passwordid parameter.  This provides the ID of a previously created secret object containing the password for decryption.

The members of TlsCredsProperties

2.5

The supported algorithms for asymmetric encryption ciphers

rsa

RSA algorithm

7.1

The type of asymmetric keys.

public

public key

private

private key

7.1

The padding algorithm for RSA.

raw

no padding used

pkcs1

pkcs1#v1.5

7.1

Specific parameters for RSA algorithm.

hash-alg: QCryptoHashAlgo

QCryptoHashAlgo

padding-alg: QCryptoRSAPaddingAlgo

QCryptoRSAPaddingAlgo

7.1

The options that are available for all asymmetric key algorithms when creating a new QCryptoAkCipher.

alg: QCryptoAkCipherAlgo

encryption cipher algorithm

The members of QCryptoAkCipherOptionsRSA when alg is "rsa"

7.1

Type of a background job.

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)

1.7

Indicates the present state of a given job in its lifetime.

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 completion.  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.

2.12

Represents command verbs that can be applied to a job.

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

change

see block-job-change (since 8.2)

2.12

Emitted when a job transitions to a different status.

id: string

The job identifier

status: JobStatus

The new job status

3.0

Pause an active job.

This command returns immediately after marking the active job for pausing.  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.

id: string

The job identifier.

3.0

Resume a paused job.

This command returns immediately after resuming a paused job. Resuming an already running job is an error.

id: string

The job identifier.

3.0

Instruct an active background job to cancel at the next opportunity. This command returns immediately after marking the active job for cancellation.

The job will cancel as soon as possible and then emit a JOB_STATUS_CHANGE event.  Usually, the status will change to ABORTING, but it is possible that a job successfully completes (e.g. because it was almost done and there was no opportunity to cancel earlier than completing the job) and transitions to PENDING instead.

id: string

The job identifier.

3.0

Manually trigger completion of an active job in the READY state.

id: string

The job identifier.

3.0

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 enabled.

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.

id: string

The job identifier.

3.0

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 PENDING 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 instruct a single member job to finalize.

id: string

The identifier of any job in the transaction, or of a job that is not part of any transaction.

3.0

Information about a job.

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 reason for the job failure.  It should not be parsed by applications.

3.0

Return information about jobs.

a list with a JobInfo for each active job

3.0

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 obtained through query-replay command (since 5.2)

1.3

format: BlockdevQcow2EncryptionFormat

The encryption format

2.10

The members of ImageInfoSpecificQCow2EncryptionBase

The members of QCryptoBlockInfoLUKS when format is "luks"

2.10

compat: string

compatibility level

data-file: string (optional)

the filename of the external data file that is stored in the image 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 encrypted (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)

1.7

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 VmdkExtentInfo

List of extent files

1.7

Information about a VMDK extent file

filename: string

Name of the extent file

format: string

Extent type (e.g. FLAT or SPARSE)

virtual-size: int

Number of bytes covered by this extent

cluster-size: int (optional)

Cluster size in bytes (for non-flat extents)

compressed: boolean (optional)

Whether this extent contains compressed data

8.0

encryption-format: RbdImageEncryptionFormat (optional)

Image encryption format

6.1

extent-size-hint: int (optional)

Extent size hint (if available)

8.0

luks

Since 2.7

rbd

Since 6.1

file

Since 8.0

qcow2

Not documented

vmdk

Not documented

1.7

data: ImageInfoSpecificQCow2

image information specific to QCOW2

1.7

data: ImageInfoSpecificVmdk

image information specific to VMDK

6.1

data: QCryptoBlockInfoLUKS

image information specific to LUKS

2.7

data: ImageInfoSpecificRbd

image information specific to RBD

6.1

data: ImageInfoSpecificFile

image information specific to files

8.0

A discriminated record of image format specific information structures.

type: ImageInfoSpecificKind

block driver name

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"

The members of ImageInfoSpecificFileWrapper when type is "file"

1.7

Information about a QEMU image file

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

format-specific: ImageInfoSpecific (optional)

structure supplying additional format-specific information (since 1.7)

8.0

Information about a QEMU image file, and potentially its backing image

backing-image: ImageInfo (optional)

info of the backing image

The members of BlockNodeInfo

1.3

Information about all nodes in the block graph starting at some node, annotated with information about that node in relation to its parent.

name: string

Child name of the root node in the BlockGraphInfo struct, in its role as the child of some undescribed parent node

info: BlockGraphInfo

Block graph information starting at this node

8.0

Information about all nodes in a block (sub)graph in the form of BlockNodeInfo data.  The base BlockNodeInfo struct contains the information for the (sub)graph's root node.

children: array of BlockChildInfo

Array of links to this node's child nodes' information

The members of BlockNodeInfo

8.0

Information about a QEMU image file check

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

1.4

Mapping information from a virtual block range to a host file range

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 particular, 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

compressed: boolean

true if the data is stored compressed (since 8.2)

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

2.6

Cache mode information for a block device

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

2.3

Information about the backing device for a block device.

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)

0.14

An enumeration of block device I/O status.

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

1.0

Block dirty bitmap information.

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.  (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. (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-bitmap-remove.  (Since 4.0)

1.3

An enumeration of flags that a bitmap can report to the user.

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 usage, 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.

4.0

Qcow2 bitmap information.

name: string

the name of the bitmap

granularity: int

granularity of the bitmap in bytes

flags: array of Qcow2BitmapInfoFlags

flags of the bitmap

4.0

Block latency histogram.

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, one more element than boundaries has.  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

4.0

Block device information.  This structure describes a virtual device and the backing device associated with it.

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

0.14

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.

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 bitmaps.  (since 5.1)

2.10

Get a list of BlockInfo for all virtual block devices.

a list of BlockInfo describing each virtual block device. Filter nodes that were created implicitly are skipped over.

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"
         }
      ]
   }

Statistics of a block device during a given interval of time.

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_zone_append_latency_ns: int

Minimum latency of zone append operations in the defined interval, in nanoseconds (since 8.1)

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_zone_append_latency_ns: int

Maximum latency of zone append operations in the defined interval, in nanoseconds (since 8.1)

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_zone_append_latency_ns: int

Average latency of zone append operations in the defined interval, in nanoseconds (since 8.1)

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 interval.

avg_wr_queue_depth: number

Average number of pending write operations in the defined interval.

avg_zone_append_queue_depth: number

Average number of pending zone append operations in the defined interval (since 8.1).

2.5

Statistics of a virtual block device or a block backing device.

rd_bytes: int

The number of bytes read by the device.

wr_bytes: int

The number of bytes written by the device.

zone_append_bytes: int

The number of bytes appended by the zoned devices (since 8.1)

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.

zone_append_operations: int

The number of zone append operations performed by the zoned devices (since 8.1)

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).

zone_append_total_time_ns: int

Total time spent on zone append writes in nanoseconds (since 8.1)

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 request (Since 2.3).

wr_merged: int

Number of write requests that have been merged into another request (Since 2.3).

zone_append_merged: int

Number of zone append requests that have been merged into another request (since 8.1)

unmap_merged: int

Number of unmap requests that have been merged into another request (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_zone_append_operations: int

The number of failed zone append write operations performed by the zoned devices (since 8.1)

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_zone_append_operations: int

The number of invalid zone append operations performed by the zoned device (since 8.1)

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 statistics (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)

zone_append_latency_histogram: BlockLatencyHistogramInfo (optional)

BlockLatencyHistogramInfo. (since 8.1)

flush_latency_histogram: BlockLatencyHistogramInfo (optional)

BlockLatencyHistogramInfo.  (Since 4.0)

0.14

File driver statistics

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.

4.2

NVMe driver statistics

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.

5.2

Block driver specific statistics

driver: BlockdevDriver

block driver name

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"

4.2

Statistics of a virtual block device or a block backing device.

device: string (optional)

If the stats are for a virtual block device, the name corresponding 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 protocol, this field is omitted

backing: BlockStats (optional)

This describes the backing block device if it has one. (Since 2.0)

0.14

Query the BlockStats for all virtual block devices.

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 before - query all the device backends, recursively including their "parent" and "backing".  Filter nodes that were created implicitly are skipped over in this mode.  (Since 2.3)

A list of BlockStats for each virtual block devices.

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
            }
         }
      ]
   }

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

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)

1.3

An enumeration of possible behaviors for the initial synchronization phase of storage mirroring.

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) Behavior on completion is determined by the BitmapSyncMode.

1.3

An enumeration of possible behaviors for the synchronization of a bitmap when used for data copy operations.

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.

4.2

An enumeration whose values tell the mirror block job when to trigger writes to the target.

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.

3.0

Information specific to mirror block jobs.

actively-synced: boolean

Whether the source is actively synced to the target, i.e. same data and new writes are done synchronously to both.

8.2

Information about a long-running block device operation.

type: JobType

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 directions.

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)

The members of BlockJobInfoMirror when type is "mirror"

1.1

Return information about long-running block device operations.

a list of BlockJobInfo for each active block job

1.1

Resize a block image while a guest is running.

Either device or node-name must be set but not both.

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

• If device is not a valid block device, DeviceNotFound

0.14

Example:

-> { "execute": "block_resize",
     "arguments": { "device": "scratch", "size": 1073741824 } }
<- { "return": {} }

An enumeration that tells QEMU how to set the backing file path in a new image file.

existing

QEMU should look for an existing image file.

absolute-paths

QEMU should create a new image with absolute paths for the backing file.  If there is no backing file available, the new image will not be backed either.

1.1

Either device or node-name must be set but not both.

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 'absolute-paths'.

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).

2.5

Optional parameters for backup.  These parameters don't affect functionality, but may significantly affect performance.

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.

min-cluster-size: int (optional)

Minimum size of blocks used by copy-before-write and background copy operations.  Has to be a power of 2.  No effect if smaller than the maximum of the target's cluster size and 64 KiB.  Default 0.  (Since 9.2)

6.0

job-id: string (optional)

identifier for the newly-created block job.  If omitted, the device 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. (default: 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 supports 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 autogenerated.  (Since: 4.2)

discard-source: boolean (optional)

Discard blocks on source which have already been copied to the target.  (Since 9.1)

x-perf: BackupPerf (optional)

Performance options.  (Since 6.0)

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.

4.2

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 destination.  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 'absolute-paths'.

The members of BackupCommon

1.6

target: string

the device name or node-name of the backup target node.

The members of BackupCommon

2.3

Takes a synchronous snapshot of a block device.

The members of BlockdevSnapshotSync

• If device is not a valid block device, DeviceNotFound

0.14

Example:

-> { "execute": "blockdev-snapshot-sync",
     "arguments": { "device": "ide-hd0",
                    "snapshot-file":
                    "/some/place/my-image",
                    "format": "qcow2" } }
<- { "return": {} }

Takes a snapshot of a block device.

Take a snapshot, by installing 'node' as the backing image of 'overlay'.  Additionally, if 'node' is associated with a block device, the block device changes to using 'overlay' as its new active image.

The members of BlockdevSnapshot

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)

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 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.

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 image-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.

• If "device" does not exist or cannot be determined, DeviceNotFound

2.1

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 itself.  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 resized to be the same size as top.  If top is smaller than the base image, 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 yourself once the commit operation successfully completes.

job-id: string (optional)

identifier for the newly-created block job.  If omitted, the device 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 specified, 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 error.

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 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)

backing-mask-protocol: boolean (optional)

If true, replace any protocol mentioned in the 'backing file format' with 'raw', rather than storing the protocol name as the backing format.  Can be used even when no image header will be updated (default false; since 9.0).

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)

deprecated

Members base and top are deprecated.  Use base-node and top-node instead.

• If device does not exist, DeviceNotFound

1.3

Example:

-> { "execute": "block-commit",
     "arguments": { "device": "virtio0",
                    "top": "/tmp/snap1.qcow2" } }
<- { "return": {} }

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.

The members of DriveBackup

deprecated

This command is deprecated.  Use blockdev-backup instead.

• If device is not a valid block device, GenericError

1.6

Example:

-> { "execute": "drive-backup",
     "arguments": { "device": "drive0",
                    "sync": "full",
                    "target": "backup.img" } }
<- { "return": {} }

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.

The members of BlockdevBackup

• If device is not a valid block device, DeviceNotFound

2.3

Example:

-> { "execute": "blockdev-backup",
     "arguments": { "device": "src-id",
                    "sync": "full",
                    "target": "tgt-id" } }
<- { "return": {} }

Get the named block driver list

flat: boolean (optional)

Omit the nested data about backing image ("backing-image" key) if true.  Default is false (Since 5.0)

the list of BlockDeviceInfo

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
                      }
                   } } ] }

block-backend

corresponds to BlockBackend

block-job

corresponds to BlockJob

block-driver

corresponds to BlockDriverState

4.0

id: int

Block graph node identifier.  This id is generated only for x-debug-query-block-graph and does not relate to any other identifiers 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).

4.0

Enum of base block permissions.

consistent-read

A user that has the "permission" of consistent reads is guaranteed that their view of the contents of the block device is complete 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 maintained in a few situations like for intermediate nodes of a commit 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 sufficient to perform an unchanging write.

resize

This permission is required to change the size of a block node.

4.0

Block Graph edge description for x-debug-query-block-graph.

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

4.0

Block Graph - list of nodes and list of edges.

nodes: array of XDbgBlockGraphNode

Not documented

edges: array of XDbgBlockGraphEdge

Not documented

4.0

Get the block graph.

unstable

This command is meant for debugging.

4.0

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 format of the source.

The members of DriveMirror

• If device is not a valid block device, GenericError

1.3

Example:

-> { "execute": "drive-mirror",
     "arguments": { "device": "ide-hd0",
                    "target": "/some/place/my-image",
                    "sync": "full",
                    "format": "qcow2" } }
<- { "return": {} }

A set of parameters describing drive mirror setup.

job-id: string (optional)

identifier for the newly-created block job.  If omitted, the device 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 destination.  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 broken Quorum files.  By default, device is replaced, although implicitly created filters on it are kept.  (Since 2.1)

mode: NewImageMode (optional)

whether and how QEMU should create a new image, default is 'absolute-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 supports 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)

1.3

node: string

name of device/node which the bitmap is tracking

name: string

name of the dirty bitmap

2.4

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-bitmap-add

persistent: boolean (optional)

the bitmap is persistent, i.e. it will be saved to the corresponding 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)

2.4

local: string

name of the bitmap, attached to the same node as target bitmap.

external: BlockDirtyBitmap

bitmap with specified node

4.1

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 specified BlockDirtyBitmap elements.  The latter are supported since 4.1.

4.0

Create a dirty bitmap with a name on the node, and start tracking the writes.

The members of BlockDirtyBitmapAdd

• If node is not a valid block device or node, DeviceNotFound
• If name is already taken, GenericError

2.4

Example:

-> { "execute": "block-dirty-bitmap-add",
     "arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }

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.

The members of BlockDirtyBitmap

• If node is not a valid block device or node, DeviceNotFound
• If name is not found, GenericError
• if name is frozen by an operation, GenericError

2.4

Example:

-> { "execute": "block-dirty-bitmap-remove",
     "arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }

Clear (reset) a dirty bitmap on the device, so that an incremental backup from this point in time forward will only backup clusters modified after this clear operation.

The members of BlockDirtyBitmap

• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError

2.4

Example:

-> { "execute": "block-dirty-bitmap-clear",
     "arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }

Enables a dirty bitmap so that it will begin tracking disk changes.

The members of BlockDirtyBitmap

• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError

4.0

Example:

-> { "execute": "block-dirty-bitmap-enable",
     "arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }

Disables a dirty bitmap so that it will stop tracking disk changes.

The members of BlockDirtyBitmap

• If node is not a valid block device, DeviceNotFound
• If name is not found, GenericError

4.0

Example:

-> { "execute": "block-dirty-bitmap-disable",
     "arguments": { "node": "drive0", "name": "bitmap0" } }
<- { "return": {} }

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 checkpoints, or in simpler usages, to copy bitmaps.

The members of BlockDirtyBitmapMerge

• 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, GenericError

4.0

Example:

-> { "execute": "block-dirty-bitmap-merge",
     "arguments": { "node": "drive0", "target": "bitmap0",
                    "bitmaps": ["bitmap1"] } }
<- { "return": {} }

SHA256 hash of dirty bitmap data

sha256: string

ASCII representation of SHA256 bitmap hash

2.10

Get bitmap SHA256.

The members of BlockDirtyBitmap

unstable

This command is meant for debugging.

BlockDirtyBitmapSha256

• If node is not a valid block device, DeviceNotFound
• If name is not found or if hashing has failed, GenericError

2.10

Start mirroring a block device's writes to a new destination.

job-id: string (optional)

identifier for the newly-created block job.  If omitted, the device 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 broken Quorum files.  By default, device is replaced, although implicitly 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 supports 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 option 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)

2.6

Example:

-> { "execute": "blockdev-mirror",
     "arguments": { "device": "ide-hd0",
                    "target": "target0",
                    "sync": "full" } }
<- { "return": {} }

A set of parameters describing block throttling.

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)

deprecated

Member device is deprecated.  Use id instead.

1.1

Limit parameters for throttling.  Since some limit combinations are illegal, 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.

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

2.11

Properties for throttle-group objects.

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

unstable

All members starting with x- are aliases for the same key without x- in the limits object.  This is not a stable interface and may be removed or changed incompatibly in the future.  Use limits for a supported stable interface.

2.11

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 operations 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 versions 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 backing 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 instead of modifying device itself.

job-id: string (optional)

identifier for the newly-created block job.  If omitted, the device 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 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 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)

backing-mask-protocol: boolean (optional)

If true, replace any protocol mentioned in the 'backing file format' with 'raw', rather than storing the protocol name as the backing format.  Can be used even when no image header will be updated (default false; since 9.0).

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 option 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)

• If device does not exist, DeviceNotFound.

1.1

Example:

-> { "execute": "block-stream",
     "arguments": { "device": "virtio0",
                    "base": "/tmp/master.qcow2" } }
<- { "return": {} }

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.

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. Defaults to 0.

• If no background operation is active on this device, DeviceNotActive

1.1

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 visible when enumerated using query-block-jobs.

Note that if you issue 'block-job-cancel' after 'drive-mirror' has indicated (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 cancellation.

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.

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)

• If no background operation is active on this device, DeviceNotActive

1.1

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 automatically resumes it.

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.

• If no background operation is active on this device, DeviceNotActive

1.3

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.

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.

• If no background operation is active on this device, DeviceNotActive

1.3

Manually trigger completion of an active background block operation. This is supported for drive mirroring, where it also switches the device to write to the target path only.  The ability to complete is signaled with a BLOCK_JOB_READY event.

This command completes an active background block operation synchronously.  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/werror arguments that were specified when starting the operation.

A cancelled or paused job cannot be completed.

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.

• If no background operation is active on this device, DeviceNotActive

1.3

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.

id: string

The job identifier.

2.12

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.

id: string

The job identifier.

2.12

copy-mode: MirrorCopyMode

Switch to this copy mode.  Currently, only the switch from 'background' to 'write-blocking' is implemented.

8.2

Block job options that can be changed after job creation.

id: string

The job identifier

type: JobType

The job type

The members of BlockJobChangeOptionsMirror when type is "mirror"

8.2

Change the block job's options.

The members of BlockJobChangeOptions

8.2

Determines how to handle discard requests.

ignore

Ignore the request

unmap

Forward as an unmap request

2.9

Describes the operation mode for the automatic conversion of plain zero writes by the OS to driver specific optimized zero write commands.

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 device.

2.1

Selects the AIO backend to handle I/O requests

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)

2.9

Includes cache-related options for block devices

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)

2.9

Drivers that are supported in block device operations.

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

deprecated

Member gluster is deprecated because GlusterFS development ceased.

2.9

Driver specific block device options for the file backend.

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 submission 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.  (default: 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 (default: 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)

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 allows giving QEMU write permissions only on demand when an operation actually needs write access.

unstable

Member x-check-cache-dropped is meant for debugging.

2.9

Driver specific block device options for the null backend.

size: int (optional)

size of the device in bytes.

latency-ns: int (optional)

emulated latency (in nanoseconds) in processing requests.  Default 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)

2.9

Driver specific block device options for the NVMe backend.

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.

2.12

Driver specific block device options for the vvfat protocol.

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 traditionally 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)

2.9

Driver specific block device options for image format that have no option besides their data source.

file: BlockdevRef

reference to or definition of the data source block device

2.9

Driver specific block device options for LUKS.

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.

header: BlockdevRef (optional)

block device holding a detached LUKS header.  (since 9.0)

The members of BlockdevOptionsGenericFormat

2.9

Driver specific block device options for image format that have no option besides their data source and an optional backing file.

backing: BlockdevRefOrNull (optional)

reference to or definition of the backing file block device, null disables the backing file entirely.  Defaults to the backing file stored the image file.

The members of BlockdevOptionsGenericFormat

2.9

General overlap check modes.

none

Do not perform any checks

constant

Perform only checks which can be done in constant time and without reading anything from disk

cached

Perform only checks which can be done without reading anything from disk

all

Perform all available overlap checks

2.9

Structure of flags for each metadata structure.  Setting a field to 'true' makes QEMU guard that Qcow2 format structure against unintended overwriting.  See Qcow2 format specification for detailed information on these structures.  The default value is chosen according to the template given.

template: Qcow2OverlapCheckMode (optional)

Specifies a template mode which can be adjusted using the other flags, defaults to 'cached'

main-header: boolean (optional)

Qcow2 format header

active-l1: boolean (optional)

Qcow2 active L1 table

active-l2: boolean (optional)

Qcow2 active L2 table

refcount-table: boolean (optional)

Qcow2 refcount table

refcount-block: boolean (optional)

Qcow2 refcount blocks

snapshot-table: boolean (optional)

Qcow2 snapshot table

inactive-l1: boolean (optional)

Qcow2 inactive L1 tables

inactive-l2: boolean (optional)

Qcow2 inactive L2 tables

bitmap-directory: boolean (optional)

Qcow2 bitmap directory (since 3.0)

2.9

Specifies which metadata structures should be guarded against unintended overwriting.

flags: Qcow2OverlapCheckFlags

set of flags for separate specification of each metadata structure type

mode: Qcow2OverlapCheckMode

named mode which chooses a specific set of flags

2.9

aes

AES-CBC with plain64 initialization vectors

2.10

format: BlockdevQcowEncryptionFormat

encryption format

The members of QCryptoBlockOptionsQCow when format is "aes"

2.10

Driver specific block device options for qcow.

encrypt: BlockdevQcowEncryption (optional)

Image decryption options.  Mandatory for encrypted images, except when doing a metadata-only probe of the image.

The members of BlockdevOptionsGenericCOWFormat

2.10

aes

AES-CBC with plain64 initialization vectors

luks

Not documented

2.10

format: BlockdevQcow2EncryptionFormat

encryption format

The members of QCryptoBlockOptionsQCow when format is "aes"

The members of QCryptoBlockOptionsLUKS when format is "luks"

2.10

Filter driver intended to be inserted between format and protocol node and do preallocation in protocol node on write.

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

6.0

Driver specific block device options for qcow2.

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

discard-no-unref: boolean (optional)

when enabled, data clusters will remain preallocated when they are no longer used, e.g. because they are discarded or converted to zero clusters.  As usual, whether the old data is discarded or kept on the protocol level (i.e. in the image file) depends on the setting of the pass-discard-request option.  Keeping the clusters preallocated prevents qcow2 fragmentation that would otherwise be caused by freeing and re-allocating them later.  Besides potential performance degradation, such fragmentation can lead to increased allocation of clusters past the end of the image file, resulting in image files whose file length can grow much larger than their guest disk size would suggest.  If image file length is of concern (e.g. when storing qcow2 images directly on block devices), you should consider enabling this option.  (since 8.1)

overlap-check: Qcow2OverlapChecks (optional)

which overlap checks to perform for writes to the image, defaults 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

2.9

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

2.12

md5

The given hash is an md5 hash

sha1

The given hash is an sha1 hash

sha256

The given hash is an sha256 hash

2.12

type: SshHostKeyCheckHashType

The hash algorithm used for the hash

hash: string

The expected hash value

2.12

mode: SshHostKeyCheckMode

How to check the host key

The members of SshHostKeyHash when mode is "hash"

2.12

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)

2.9

Trigger events supported by blkdebug.

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

2.9

Kinds of I/O that blkdebug can inject errors in.

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()

4.1

Describes a single error injection for blkdebug.

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 injected; 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; defaults to false

immediately: boolean (optional)

fail immediately; defaults to false

2.9

Describes a single state-change event for blkdebug.

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

2.9

Driver specific block device options for blkdebug.

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 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)

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 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-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 default (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).  Defaults 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)

2.9

Driver specific block device options for blklogwrites.

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 granularity 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)

3.0

Driver specific block device options for blkverify.

test: BlockdevRef

block device to be tested

raw: BlockdevRef

raw image used for verification

2.9

Driver specific block device options for blkreplay.

image: BlockdevRef

disk image which should be controlled with blkreplay

4.2

An enumeration of quorum read patterns.

quorum

read all the children and do a quorum vote on reads

fifo

read only from the first child that has not failed

2.9

Driver specific block device options for Quorum

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)

2.9

Driver specific block device options for Gluster

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)

2.9

Driver specific block device options for the io_uring backend.

filename: string

path to the image file

7.2

CONFIG_BLKIO

Driver specific block device options for the nvme-io_uring backend.

path: string

path to the NVMe namespace's character device (e.g. /dev/ng0n1).

7.2

CONFIG_BLKIO

Driver specific block device options for the virtio-blk-vfio-pci backend.

path: string

path to the PCI device's sysfs directory (e.g. /sys/bus/pci/devices/0000:00:01.0).

7.2

CONFIG_BLKIO

Driver specific block device options for the virtio-blk-vhost-user backend.

path: string

path to the vhost-user UNIX domain socket.

7.2

CONFIG_BLKIO

Driver specific block device options for the virtio-blk-vhost-vdpa backend.

path: string

path to the vhost-vdpa character device.

fdset

Member path supports the special "/dev/fdset/N" path (since 8.1)

7.2

CONFIG_BLKIO

An enumeration of libiscsi transport types

tcp

Not documented

iser

Not documented

2.9

An enumeration of header digests supported by libiscsi

crc32c

Not documented

none

Not documented

crc32c-none

Not documented

none-crc32c

Not documented

2.9

Driver specific block device options for iscsi

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 option is not specified, an initiator name is generated automatically.

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.

2.9

cephx

Not documented

none

Not documented

3.0

luks-any

Used for opening either luks or luks2 (Since 8.0)

luks

Not documented

luks2

Not documented

6.1

key-secret: string

ID of a QCryptoSecret object providing a passphrase for unlocking the encryption

6.1

cipher-alg: QCryptoCipherAlgo (optional)

The encryption algorithm

The members of RbdEncryptionOptionsLUKSBase

6.1

The members of RbdEncryptionOptionsLUKSBase

6.1

The members of RbdEncryptionOptionsLUKSBase

6.1

The members of RbdEncryptionOptionsLUKSBase

8.0

The members of RbdEncryptionCreateOptionsLUKSBase

6.1

The members of RbdEncryptionCreateOptionsLUKSBase

6.1

format: RbdImageEncryptionFormat

Encryption format.

parent: RbdEncryptionOptions (optional)

Parent image encryption options (for cloned images).  Can be left unspecified if this cloned image is encrypted using the same format and secret as its parent image (i.e. not explicitly formatted) or if its parent image is not encrypted.  (Since 8.0)

The members of RbdEncryptionOptionsLUKS when format is "luks"

The members of RbdEncryptionOptionsLUKS2 when format is "luks2"

The members of RbdEncryptionOptionsLUKSAny when format is "luks-any"

6.1

format: RbdImageEncryptionFormat

Encryption format.

The members of RbdEncryptionCreateOptionsLUKS when format is "luks"

The members of RbdEncryptionCreateOptionsLUKS2 when format is "luks2"

6.1

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 configuration option "auth_client_required".  (Since 3.0)

key-secret: string (optional)

ID of a QCryptoSecret object providing a key for cephx authentication.  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.

2.9

An enumeration of replication modes.

primary

Primary mode, the vm's state will be sent to secondary QEMU.

secondary

Secondary mode, receive the vm's state from primary QEMU.

2.9

CONFIG_REPLICATION

Driver specific block device options for replication

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

2.9

CONFIG_REPLICATION

An enumeration of NFS transport types

inet

TCP transport

2.9

Captures the address of the socket

type: NFSTransport

transport type used for NFS (only TCP supported)

host: string

host address for NFS server

2.9

Driver specific block device option for NFS

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)

2.9

Driver specific block device options shared by all protocols supported by the curl backend.

url: string

URL of the image file

readahead: int (optional)

Size of the read-ahead cache; must be a multiple of 512 (defaults 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 authentication (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 authentication (defaults to no password)

2.9

Driver specific block device options for HTTP connections over the curl backend.  URLs must start with "http://".

cookie: string (optional)

List of cookies to set; format is "name1=content1; name2=content2;" as explained by CURLOPT_COOKIE(3).  Defaults to no cookies.

cookie-secret: string (optional)

ID of a QCryptoSecret object providing the cookie data in a secure way.  See cookie for the format.  (since 2.10)

The members of BlockdevOptionsCurlBase

2.9

Driver specific block device options for HTTPS connections over the curl backend.  URLs must start with "https://".

cookie: string (optional)

List of cookies to set; format is "name1=content1; name2=content2;" as explained by CURLOPT_COOKIE(3).  Defaults to no cookies.

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 secure way.  See cookie for the format.  (since 2.10)

The members of BlockdevOptionsCurlBase

2.9

Driver specific block device options for FTP connections over the curl backend.  URLs must start with "ftp://".

The members of BlockdevOptionsCurlBase

2.9

Driver specific block device options for FTPS connections over the curl backend.  URLs must start with "ftps://".

sslverify: boolean (optional)

Whether to verify the SSL certificate's validity (defaults to true)

The members of BlockdevOptionsCurlBase

2.9

Driver specific block device options for NBD.

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 reconnect 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)

unstable

Member x-dirty-bitmap is experimental.

2.9

Driver specific block device options for the raw driver.

offset: int (optional)

position where the block device starts

size: int (optional)

the assumed size of the device

The members of BlockdevOptionsGenericFormat

2.9

Driver specific block device options for the throttle driver

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

2.11

Driver specific block device options for the copy-on-read driver.

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

6.0

An enumeration of possible behaviors for copy-before-write operation failures.

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.

7.1

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.

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 bitmap 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 respective copy-before-write operation will fail, and the on-cbw-error parameter will decide how this failure is handled. Default 0.  (Since 7.1)

min-cluster-size: int (optional)

Minimum size of blocks used by copy-before-write operations.  Has to be a power of 2.  No effect if smaller than the maximum of the target's cluster size and 64 KiB.  Default 0. (Since 9.2)

The members of BlockdevOptionsGenericFormat

6.2

Options for creating a block device.  Many options are available for all block devices, independent of the block driver:

driver: BlockdevDriver

block driver name

node-name: string (optional)

the node name of the new node (Since 2.0).  This option is required 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 characters.

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, either generally or in certain configurations.  In this case, the default value does not work and the option must be specified explicitly.

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. depending on whether the image file is writable or whether a writing 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 "blklogwrites"

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_uring" (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 "snapshot-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 "virtio-blk-vfio-pci" (If: CONFIG_BLKIO)

The members of BlockdevOptionsVirtioBlkVhostUser when driver is "virtio-blk-vhost-user" (If: CONFIG_BLKIO)

The members of BlockdevOptionsVirtioBlkVhostVdpa when driver is "virtio-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"

2.9

Reference to a block device.

definition: BlockdevOptions

defines a new block device inline

reference: string

references the ID of an existing block device

2.9

Reference to a block device.