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HXCOMM QMP dispatch table and documentation

HXCOMM Text between SQMP and EQMP is copied to the QMP documention file and

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SQMP

                        QMP Supported Commands

                        ----------------------

This document describes all commands currently supported by QMP.

Most of the time their usage is exactly the same as in the user Monitor, this

means that any other document which also describe commands (the manpage,

QEMU's manual, etc) can and should be consulted.

QMP has two types of commands: regular and query commands. Regular commands

usually change the Virtual Machine's state someway, while query commands just

return information. The sections below are divided accordingly.

It's important to observe that all communication examples are formatted in

a reader-friendly way, so that they're easier to understand. However, in real

protocol usage, they're emitted as a single line.

Also, the following notation is used to denote data flow:

-> data issued by the Client

<- Server data response

Please, refer to the QMP specification (QMP/qmp-spec.txt) for detailed

information on the Server command and response formats.

NOTE: This document is temporary and will be replaced soon.

1. Stability Considerations

===========================

The current QMP command set (described in this file) may be useful for a

number of use cases, however it's limited and several commands have bad

defined semantics, specially with regard to command completion.

These problems are going to be solved incrementally in the next QEMU releases

and we're going to establish a deprecation policy for badly defined commands.

If you're planning to adopt QMP, please observe the following:

    1. The deprecation policy will take effect and be documented soon, please

       check the documentation of each used command as soon as a new release of

       QEMU is available

    2. DO NOT rely on anything which is not explicit documented

    3. Errors, in special, are not documented. Applications should NOT check

       for specific errors classes or data (it's strongly recommended to only

       check for the "error" key)

2. Regular Commands

===================

Server's responses in the examples below are always a success response, please

refer to the QMP specification for more details on error responses.

EQMP

    {

        .name       = "quit",

        .args_type  = "",

        .mhandler.cmd_new = qmp_marshal_input_quit,

    },

SQMP

quit

----

Quit the emulator.

Arguments: None.

Example:

-> { "execute": "quit" }

<- { "return": {} }

EQMP

    {

        .name       = "eject",

        .args_type  = "force:-f,device:B",

        .params     = "[-f] device",

        .help       = "eject a removable medium (use -f to force it)",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_eject,

    },

SQMP

eject

-----

Eject a removable medium.

Arguments: 

- force: force ejection (json-bool, optional)

- device: device name (json-string)

Example:

-> { "execute": "eject", "arguments": { "device": "ide1-cd0" } }

<- { "return": {} }

Note: The "force" argument defaults to false.

EQMP

    {

        .name       = "change",

        .args_type  = "device:B,target:F,arg:s?",

        .params     = "device filename [format]",

        .help       = "change a removable medium, optional format",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_change,

    },

SQMP

change

------

Change a removable medium or VNC configuration.

Arguments:

- "device": device name (json-string)

- "target": filename or item (json-string)

- "arg": additional argument (json-string, optional)

Examples:

1. Change a removable medium

-> { "execute": "change",

             "arguments": { "device": "ide1-cd0",

                            "target": "/srv/images/Fedora-12-x86_64-DVD.iso" } }

<- { "return": {} }

2. Change VNC password

-> { "execute": "change",

             "arguments": { "device": "vnc", "target": "password",

                            "arg": "foobar1" } }

<- { "return": {} }

EQMP

    {

        .name       = "screendump",

        .args_type  = "filename:F",

        .params     = "filename",

        .help       = "save screen into PPM image 'filename'",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_screen_dump,

    },

SQMP

screendump

----------

Save screen into PPM image.

Arguments:

- "filename": file path (json-string)

Example:

-> { "execute": "screendump", "arguments": { "filename": "/tmp/image" } }

<- { "return": {} }

EQMP

    {

        .name       = "stop",

        .args_type  = "",

        .mhandler.cmd_new = qmp_marshal_input_stop,

    },

SQMP

stop

----

Stop the emulator.

Arguments: None.

Example:

-> { "execute": "stop" }

<- { "return": {} }

EQMP

    {

        .name       = "cont",

        .args_type  = "",

        .params     = "",

        .help       = "resume emulation",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_cont,

    },

SQMP

cont

----

Resume emulation.

Arguments: None.

Example:

-> { "execute": "cont" }

<- { "return": {} }

EQMP

    {

        .name       = "system_reset",

        .args_type  = "",

        .mhandler.cmd_new = qmp_marshal_input_system_reset,

    },

SQMP

system_reset

------------

Reset the system.

Arguments: None.

Example:

-> { "execute": "system_reset" }

<- { "return": {} }

EQMP

    {

        .name       = "system_powerdown",

        .args_type  = "",

        .params     = "",

        .help       = "send system power down event",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_system_powerdown,

    },

SQMP

system_powerdown

----------------

Send system power down event.

Arguments: None.

Example:

-> { "execute": "system_powerdown" }

<- { "return": {} }

EQMP

    {

        .name       = "device_add",

        .args_type  = "device:O",

        .params     = "driver[,prop=value][,...]",

        .help       = "add device, like -device on the command line",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_device_add,

    },

SQMP

device_add

----------

Add a device.

Arguments:

- "driver": the name of the new device's driver (json-string)

- "bus": the device's parent bus (device tree path, json-string, optional)

- "id": the device's ID, must be unique (json-string)

- device properties

Example:

-> { "execute": "device_add", "arguments": { "driver": "e1000", "id": "net1" } }

<- { "return": {} }

Notes:

(1) For detailed information about this command, please refer to the

    'docs/qdev-device-use.txt' file.

(2) It's possible to list device properties by running QEMU with the

    "-device DEVICE,\?" command-line argument, where DEVICE is the device's name

EQMP

    {

        .name       = "device_del",

        .args_type  = "id:s",

        .params     = "device",

        .help       = "remove device",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_device_del,

    },

SQMP

device_del

----------

Remove a device.

Arguments:

- "id": the device's ID (json-string)

Example:

-> { "execute": "device_del", "arguments": { "id": "net1" } }

<- { "return": {} }

EQMP

    {

        .name       = "cpu",

        .args_type  = "index:i",

        .params     = "index",

        .help       = "set the default CPU",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_cpu_set,

    },

SQMP

cpu

---

Set the default CPU.

Arguments:

- "index": the CPU's index (json-int)

Example:

-> { "execute": "cpu", "arguments": { "index": 0 } }

<- { "return": {} }

Note: CPUs' indexes are obtained with the 'query-cpus' command.

EQMP

    {

        .name       = "memsave",

        .args_type  = "val:l,size:i,filename:s",

        .params     = "addr size file",

        .help       = "save to disk virtual memory dump starting at 'addr' of size 'size'",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_memory_save,

    },

SQMP

memsave

-------

Save to disk virtual memory dump starting at 'val' of size 'size'.

Arguments:

- "val": the starting address (json-int)

- "size": the memory size, in bytes (json-int)

- "filename": file path (json-string)

Example:

-> { "execute": "memsave",

             "arguments": { "val": 10,

                            "size": 100,

                            "filename": "/tmp/virtual-mem-dump" } }

<- { "return": {} }

Note: Depends on the current CPU.

EQMP

    {

        .name       = "pmemsave",

        .args_type  = "val:l,size:i,filename:s",

        .params     = "addr size file",

        .help       = "save to disk physical memory dump starting at 'addr' of size 'size'",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_physical_memory_save,

    },

SQMP

pmemsave

--------

Save to disk physical memory dump starting at 'val' of size 'size'.

Arguments:

- "val": the starting address (json-int)

- "size": the memory size, in bytes (json-int)

- "filename": file path (json-string)

Example:

-> { "execute": "pmemsave",

             "arguments": { "val": 10,

                            "size": 100,

                            "filename": "/tmp/physical-mem-dump" } }

<- { "return": {} }

EQMP

    {

        .name       = "inject-nmi",

        .args_type  = "",

        .params     = "",

        .help       = "",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_inject_nmi,

    },

SQMP

inject-nmi

----------

Inject an NMI on guest's CPUs.

Arguments: None.

Example:

-> { "execute": "inject-nmi" }

<- { "return": {} }

Note: inject-nmi is only supported for x86 guest currently, it will

      returns "Unsupported" error for non-x86 guest.

EQMP

    {

        .name       = "migrate",

        .args_type  = "detach:-d,blk:-b,inc:-i,uri:s",

        .params     = "[-d] [-b] [-i] uri",

        .help       = "migrate to URI (using -d to not wait for completion)"

		      "\n\t\t\t -b for migration without shared storage with"

		      " full copy of disk\n\t\t\t -i for migration without "

		      "shared storage with incremental copy of disk "

		      "(base image shared between src and destination)",

        .user_print = monitor_user_noop,	

	.mhandler.cmd_new = do_migrate,

    },

SQMP

migrate

-------

Migrate to URI.

Arguments:

- "blk": block migration, full disk copy (json-bool, optional)

- "inc": incremental disk copy (json-bool, optional)

- "uri": Destination URI (json-string)

Example:

-> { "execute": "migrate", "arguments": { "uri": "tcp:0:4446" } }

<- { "return": {} }

Notes:

(1) The 'query-migrate' command should be used to check migration's progress

    and final result (this information is provided by the 'status' member)

(2) All boolean arguments default to false

(3) The user Monitor's "detach" argument is invalid in QMP and should not

    be used

EQMP

    {

        .name       = "migrate_cancel",

        .args_type  = "",

        .params     = "",

        .help       = "cancel the current VM migration",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_migrate_cancel,

    },

SQMP

migrate_cancel

--------------

Cancel the current migration.

Arguments: None.

Example:

-> { "execute": "migrate_cancel" }

<- { "return": {} }

EQMP

    {

        .name       = "migrate_set_speed",

        .args_type  = "value:o",

        .params     = "value",

        .help       = "set maximum speed (in bytes) for migrations",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_migrate_set_speed,

    },

SQMP

migrate_set_speed

-----------------

Set maximum speed for migrations.

Arguments:

- "value": maximum speed, in bytes per second (json-int)

Example:

-> { "execute": "migrate_set_speed", "arguments": { "value": 1024 } }

<- { "return": {} }

EQMP

    {

        .name       = "migrate_set_downtime",

        .args_type  = "value:T",

        .params     = "value",

        .help       = "set maximum tolerated downtime (in seconds) for migrations",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_migrate_set_downtime,

    },

SQMP

migrate_set_downtime

--------------------

Set maximum tolerated downtime (in seconds) for migrations.

Arguments:

- "value": maximum downtime (json-number)

Example:

-> { "execute": "migrate_set_downtime", "arguments": { "value": 0.1 } }

<- { "return": {} }

EQMP

    {

        .name       = "client_migrate_info",

        .args_type  = "protocol:s,hostname:s,port:i?,tls-port:i?,cert-subject:s?",

        .params     = "protocol hostname port tls-port cert-subject",

        .help       = "send migration info to spice/vnc client",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = client_migrate_info,

    },

SQMP

client_migrate_info

------------------

Set the spice/vnc connection info for the migration target.  The spice/vnc

server will ask the spice/vnc client to automatically reconnect using the

new parameters (if specified) once the vm migration finished successfully.

Arguments:

- "protocol":     protocol: "spice" or "vnc" (json-string)

- "hostname":     migration target hostname (json-string)

- "port":         spice/vnc tcp port for plaintext channels (json-int, optional)

- "tls-port":     spice tcp port for tls-secured channels (json-int, optional)

- "cert-subject": server certificate subject (json-string, optional)

Example:

-> { "execute": "client_migrate_info",

     "arguments": { "protocol": "spice",

                    "hostname": "virt42.lab.kraxel.org",

                    "port": 1234 } }

<- { "return": {} }

EQMP

    {

        .name       = "netdev_add",

        .args_type  = "netdev:O",

        .params     = "[user|tap|socket],id=str[,prop=value][,...]",

        .help       = "add host network device",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_netdev_add,

    },

SQMP

netdev_add

----------

Add host network device.

Arguments:

- "type": the device type, "tap", "user", ... (json-string)

- "id": the device's ID, must be unique (json-string)

- device options

Example:

-> { "execute": "netdev_add", "arguments": { "type": "user", "id": "netdev1" } }

<- { "return": {} }

Note: The supported device options are the same ones supported by the '-net'

      command-line argument, which are listed in the '-help' output or QEMU's

      manual

EQMP

    {

        .name       = "netdev_del",

        .args_type  = "id:s",

        .params     = "id",

        .help       = "remove host network device",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_netdev_del,

    },

SQMP

netdev_del

----------

Remove host network device.

Arguments:

- "id": the device's ID, must be unique (json-string)

Example:

-> { "execute": "netdev_del", "arguments": { "id": "netdev1" } }

<- { "return": {} }

EQMP

    {

        .name       = "block_resize",

        .args_type  = "device:B,size:o",

        .params     = "device size",

        .help       = "resize a block image",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_block_resize,

    },

SQMP

block_resize

------------

Resize a block image while a guest is running.

Arguments:

- "device": the device's ID, must be unique (json-string)

- "size": new size

Example:

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

<- { "return": {} }

EQMP

    {

        .name       = "blockdev-snapshot-sync",

        .args_type  = "device:B,snapshot-file:s?,format:s?",

        .params     = "device [new-image-file] [format]",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_snapshot_blkdev,

    },

SQMP

blockdev-snapshot-sync

----------------------

Synchronous snapshot of a block device. snapshot-file specifies the

target of the new image. If the file exists, or if it is a device, the

snapshot will be created in the existing file/device. If does not

exist, a new file will be created. format specifies the format of the

snapshot image, default is qcow2.

Arguments:

- "device": device name to snapshot (json-string)

- "snapshot-file": name of new image file (json-string)

- "format": format of new image (json-string, optional)

Example:

-> { "execute": "blockdev-snapshot-sync", "arguments": { "device": "ide-hd0",

                                                         "snapshot-file":

                                                        "/some/place/my-image",

                                                        "format": "qcow2" } }

<- { "return": {} }

EQMP

    {

        .name       = "balloon",

        .args_type  = "value:M",

        .params     = "target",

        .help       = "request VM to change its memory allocation (in MB)",

        .user_print = monitor_user_noop,

        .mhandler.cmd_async = do_balloon,

        .flags      = MONITOR_CMD_ASYNC,

    },

SQMP

balloon

-------

Request VM to change its memory allocation (in bytes).

Arguments:

- "value": New memory allocation (json-int)

Example:

-> { "execute": "balloon", "arguments": { "value": 536870912 } }

<- { "return": {} }

EQMP

    {

        .name       = "set_link",

        .args_type  = "name:s,up:b",

        .params     = "name on|off",

        .help       = "change the link status of a network adapter",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_set_link,

    },

SQMP

set_link

--------

Change the link status of a network adapter.

Arguments:

- "name": network device name (json-string)

- "up": status is up (json-bool)

Example:

-> { "execute": "set_link", "arguments": { "name": "e1000.0", "up": false } }

<- { "return": {} }

EQMP

    {

        .name       = "getfd",

        .args_type  = "fdname:s",

        .params     = "getfd name",

        .help       = "receive a file descriptor via SCM rights and assign it a name",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_getfd,

    },

SQMP

getfd

-----

Receive a file descriptor via SCM rights and assign it a name.

Arguments:

- "fdname": file descriptor name (json-string)

Example:

-> { "execute": "getfd", "arguments": { "fdname": "fd1" } }

<- { "return": {} }

EQMP

    {

        .name       = "closefd",

        .args_type  = "fdname:s",

        .params     = "closefd name",

        .help       = "close a file descriptor previously passed via SCM rights",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_closefd,

    },

SQMP

closefd

-------

Close a file descriptor previously passed via SCM rights.

Arguments:

- "fdname": file descriptor name (json-string)

Example:

-> { "execute": "closefd", "arguments": { "fdname": "fd1" } }

<- { "return": {} }

EQMP

    {

        .name       = "block_passwd",

        .args_type  = "device:B,password:s",

        .params     = "block_passwd device password",

        .help       = "set the password of encrypted block devices",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_block_set_passwd,

    },

SQMP

block_passwd

------------

Set the password of encrypted block devices.

Arguments:

- "device": device name (json-string)

- "password": password (json-string)

Example:

-> { "execute": "block_passwd", "arguments": { "device": "ide0-hd0",

                                               "password": "12345" } }

<- { "return": {} }

EQMP

    {

        .name       = "set_password",

        .args_type  = "protocol:s,password:s,connected:s?",

        .params     = "protocol password action-if-connected",

        .help       = "set spice/vnc password",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = set_password,

    },

SQMP

set_password

------------

Set the password for vnc/spice protocols.

Arguments:

- "protocol": protocol name (json-string)

- "password": password (json-string)

- "connected": [ keep | disconnect | fail ] (josn-string, optional)

Example:

-> { "execute": "set_password", "arguments": { "protocol": "vnc",

                                               "password": "secret" } }

<- { "return": {} }

EQMP

    {

        .name       = "expire_password",

        .args_type  = "protocol:s,time:s",

        .params     = "protocol time",

        .help       = "set spice/vnc password expire-time",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = expire_password,

    },

SQMP

expire_password

---------------

Set the password expire time for vnc/spice protocols.

Arguments:

- "protocol": protocol name (json-string)

- "time": [ now | never | +secs | secs ] (json-string)

Example:

-> { "execute": "expire_password", "arguments": { "protocol": "vnc",

                                                  "time": "+60" } }

<- { "return": {} }

EQMP

    {

        .name       = "add_client",

        .args_type  = "protocol:s,fdname:s,skipauth:b?",

        .params     = "protocol fdname skipauth",

        .help       = "add a graphics client",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = add_graphics_client,

    },

SQMP

add_client

----------

Add a graphics client

Arguments:

- "protocol": protocol name (json-string)

- "fdname": file descriptor name (json-string)

Example:

-> { "execute": "add_client", "arguments": { "protocol": "vnc",

                                             "fdname": "myclient" } }

<- { "return": {} }

EQMP

    {

        .name       = "qmp_capabilities",

        .args_type  = "",

        .params     = "",

        .help       = "enable QMP capabilities",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_qmp_capabilities,

    },

SQMP

qmp_capabilities

----------------

Enable QMP capabilities.

Arguments: None.

Example:

-> { "execute": "qmp_capabilities" }

<- { "return": {} }

Note: This command must be issued before issuing any other command.

EQMP

    {

        .name       = "human-monitor-command",

        .args_type  = "command-line:s,cpu-index:i?",

        .params     = "",

        .help       = "",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_hmp_passthrough,

    },

SQMP

human-monitor-command

---------------------

Execute a Human Monitor command.

Arguments: 

- command-line: the command name and its arguments, just like the

                Human Monitor's shell (json-string)

- cpu-index: select the CPU number to be used by commands which access CPU

             data, like 'info registers'. The Monitor selects CPU 0 if this

             argument is not provided (json-int, optional)

Example:

-> { "execute": "human-monitor-command", "arguments": { "command-line": "info kvm" } }

<- { "return": "kvm support: enabled\r\n" }