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HXCOMM QMP dispatch table and documentation

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

HXCOMM does not show up in the other formats.

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 efect 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  = "",

        .params     = "",

        .help       = "quit the emulator",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_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  = "",

        .params     = "",

        .help       = "stop emulation",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_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  = "",

        .params     = "",

        .help       = "reset the system",

        .user_print = monitor_user_noop,

        .mhandler.cmd_new = do_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       = "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:f",

        .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-number)

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       = "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       = "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       = "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.

3. Query Commands

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

HXCOMM Each query command below is inside a SQMP/EQMP section, do NOT change

HXCOMM this! We will possibly move query commands definitions inside those

HXCOMM sections, just like regular commands.

EQMP

SQMP

query-version

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

Show QEMU version.

Return a json-object with the following information:

- "qemu": A json-object containing three integer values:

    - "major": QEMU's major version (json-int)

    - "minor": QEMU's minor version (json-int)

    - "micro": QEMU's micro version (json-int)

- "package": package's version (json-string)

Example:

-> { "execute": "query-version" }

<- {

      "return":{

         "qemu":{

            "major":0,

            "minor":11,

            "micro":5

         },

         "package":""

      }

   }

EQMP

SQMP

query-commands

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

List QMP available commands.

Each command is represented by a json-object, the returned value is a json-array

of all commands.

Each json-object contain:

- "name": command's name (json-string)

Example:

-> { "execute": "query-commands" }

<- {

      "return":[

         {

            "name":"query-balloon"

         },

         {

            "name":"system_powerdown"

         }

      ]

   }

Note: This example has been shortened as the real response is too long.

EQMP

SQMP

query-chardev

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

Each device is represented by a json-object. The returned value is a json-array

of all devices.

Each json-object contain the following:

- "label": device's label (json-string)

- "filename": device's file (json-string)

Example:

-> { "execute": "query-chardev" }

<- {

      "return":[

         {

            "label":"monitor",

            "filename":"stdio"

         },

         {

            "label":"serial0",

            "filename":"vc"

         }

      ]

   }

EQMP

SQMP

query-block

-----------

Show the block devices.

Each block device information is stored in a json-object and the returned value

is a json-array of all devices.

Each json-object contain the following:

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

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

         - Possible values: "hd", "cdrom", "floppy", "unknown"

- "removable": true if the device is removable, false otherwise (json-bool)

- "locked": true if the device is locked, false otherwise (json-bool)

- "inserted": only present if the device is inserted, it is a json-object

   containing the following:

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

         - "ro": true if read-only, false otherwise (json-bool)

         - "drv": driver format name (json-string)

             - Possible values: "blkdebug", "bochs", "cloop", "cow", "dmg",

                                "file", "file", "ftp", "ftps", "host_cdrom",

                                "host_device", "host_floppy", "http", "https",

                                "nbd", "parallels", "qcow", "qcow2", "raw",

                                "tftp", "vdi", "vmdk", "vpc", "vvfat"

         - "backing_file": backing file name (json-string, optional)

         - "encrypted": true if encrypted, false otherwise (json-bool)

Example:

-> { "execute": "query-block" }

<- {

      "return":[

         {

            "device":"ide0-hd0",

            "locked":false,

            "removable":false,

            "inserted":{

               "ro":false,

               "drv":"qcow2",

               "encrypted":false,

               "file":"disks/test.img"

            },

            "type":"hd"

         },

         {

            "device":"ide1-cd0",

            "locked":false,

            "removable":true,

            "type":"cdrom"

         },

         {

            "device":"floppy0",

            "locked":false,

            "removable":true,

            "type": "floppy"

         },

         {

            "device":"sd0",

            "locked":false,

            "removable":true,

            "type":"floppy"

         }

      ]

   }

EQMP

SQMP

query-blockstats

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

Show block device statistics.

Each device statistic information is stored in a json-object and the returned

value is a json-array of all devices.

Each json-object contain the following:

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

- "stats": A json-object with the statistics information, it contains:

    - "rd_bytes": bytes read (json-int)

    - "wr_bytes": bytes written (json-int)

    - "rd_operations": read operations (json-int)

    - "wr_operations": write operations (json-int)

    - "wr_highest_offset": Highest offset of a sector written since the

                           BlockDriverState has been opened (json-int)

- "parent": 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

            (json-object, optional)

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

               }

            },

            "stats":{

               "wr_highest_offset":2821110784,

               "wr_bytes":9786368,

               "wr_operations":692,

               "rd_bytes":122739200,

               "rd_operations":36604

            }

         },

         {

            "device":"ide1-cd0",

            "stats":{

               "wr_highest_offset":0,

               "wr_bytes":0,

               "wr_operations":0,

               "rd_bytes":0,

               "rd_operations":0

            }

         },

         {