qemu/qapi-schema-guest.json
Michael Roth 3cf0bed836 qemu-ga: add guest-sync-delimited
guest-sync leaves it as an exercise to the user as to how to reliably
obtain the response to guest-sync if the client had previously read in a
partial response (due qemu-ga previously being restarted mid-"sentence"
due to reboot, forced restart, etc).

qemu-ga handles this situation on its end by having a client precede
their guest-sync request with a 0xFF byte (invalid UTF-8), which
qemu-ga/QEMU JSON parsers will treat as a flush event. Thus we can
reliably flush the qemu-ga parser state in preparation for receiving
the guest-sync request.

guest-sync-delimited provides the same functionality for a client: when
a guest-sync-delimited is issued, qemu-ga will precede it's response
with a 0xFF byte that the client can use as an indicator to flush its
buffer/parser state in preparation for reliably receiving the
guest-sync-delimited response.

It is also useful as an optimization for clients, since, after issuing a
guest-sync-delimited, clients can safely discard all stale data read
from the channel until the 0xFF is found.

More information available on the wiki:

http://wiki.qemu.org/Features/QAPI/GuestAgent#QEMU_Guest_Agent_Protocol

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2012-03-12 15:09:23 -05:00

478 lines
12 KiB
Python

# *-*- Mode: Python -*-*
##
#
# Echo back a unique integer value, and prepend to response a
# leading sentinel byte (0xFF) the client can check scan for.
#
# This is used by clients talking to the guest agent over the
# wire to ensure the stream is in sync and doesn't contain stale
# data from previous client. It must be issued upon initial
# connection, and after any client-side timeouts (including
# timeouts on receiving a response to this command).
#
# After issuing this request, all guest agent responses should be
# ignored until the response containing the unique integer value
# the client passed in is returned. Receival of the 0xFF sentinel
# byte must be handled as an indication that the client's
# lexer/tokenizer/parser state should be flushed/reset in
# preparation for reliably receiving the subsequent response. As
# an optimization, clients may opt to ignore all data until a
# sentinel value is receiving to avoid unecessary processing of
# stale data.
#
# Similarly, clients should also precede this *request*
# with a 0xFF byte to make sure the guest agent flushes any
# partially read JSON data from a previous client connection.
#
# @id: randomly generated 64-bit integer
#
# Returns: The unique integer id passed in by the client
#
# Since: 1.1
# ##
{ 'command': 'guest-sync-delimited'
'data': { 'id': 'int' },
'returns': 'int' }
##
# @guest-sync:
#
# Echo back a unique integer value
#
# This is used by clients talking to the guest agent over the
# wire to ensure the stream is in sync and doesn't contain stale
# data from previous client. All guest agent responses should be
# ignored until the provided unique integer value is returned,
# and it is up to the client to handle stale whole or
# partially-delivered JSON text in such a way that this response
# can be obtained.
#
# In cases where a partial stale response was previously
# received by the client, this cannot always be done reliably.
# One particular scenario being if qemu-ga responses are fed
# character-by-character into a JSON parser. In these situations,
# using guest-sync-delimited may be optimal.
#
# For clients that fetch responses line by line and convert them
# to JSON objects, guest-sync should be sufficient, but note that
# in cases where the channel is dirty some attempts at parsing the
# response may result in a parser error.
#
# Such clients should also precede this command
# with a 0xFF byte to make sure the guest agent flushes any
# partially read JSON data from a previous session.
#
# @id: randomly generated 64-bit integer
#
# Returns: The unique integer id passed in by the client
#
# Since: 0.15.0
##
{ 'command': 'guest-sync'
'data': { 'id': 'int' },
'returns': 'int' }
##
# @guest-ping:
#
# Ping the guest agent, a non-error return implies success
#
# Since: 0.15.0
##
{ 'command': 'guest-ping' }
##
# @GuestAgentCommandInfo:
#
# Information about guest agent commands.
#
# @name: name of the command
#
# @enabled: whether command is currently enabled by guest admin
#
# Since 1.1.0
##
{ 'type': 'GuestAgentCommandInfo',
'data': { 'name': 'str', 'enabled': 'bool' } }
##
# @GuestAgentInfo
#
# Information about guest agent.
#
# @version: guest agent version
#
# @supported_commands: Information about guest agent commands
#
# Since 0.15.0
##
{ 'type': 'GuestAgentInfo',
'data': { 'version': 'str',
'supported_commands': ['GuestAgentCommandInfo'] } }
##
# @guest-info:
#
# Get some information about the guest agent.
#
# Returns: @GuestAgentInfo
#
# Since: 0.15.0
##
{ 'command': 'guest-info',
'returns': 'GuestAgentInfo' }
##
# @guest-shutdown:
#
# Initiate guest-activated shutdown. Note: this is an asynchronous
# shutdown request, with no guaruntee of successful shutdown. Errors
# will be logged to guest's syslog.
#
# @mode: #optional "halt", "powerdown" (default), or "reboot"
#
# Returns: Nothing on success
#
# Since: 0.15.0
##
{ 'command': 'guest-shutdown', 'data': { '*mode': 'str' } }
##
# @guest-file-open:
#
# Open a file in the guest and retrieve a file handle for it
#
# @filepath: Full path to the file in the guest to open.
#
# @mode: #optional open mode, as per fopen(), "r" is the default.
#
# Returns: Guest file handle on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-open',
'data': { 'path': 'str', '*mode': 'str' },
'returns': 'int' }
##
# @guest-file-close:
#
# Close an open file in the guest
#
# @handle: filehandle returned by guest-file-open
#
# Returns: Nothing on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-close',
'data': { 'handle': 'int' } }
##
# @GuestFileRead
#
# Result of guest agent file-read operation
#
# @count: number of bytes read (note: count is *before*
# base64-encoding is applied)
#
# @buf-b64: base64-encoded bytes read
#
# @eof: whether EOF was encountered during read operation.
#
# Since: 0.15.0
##
{ 'type': 'GuestFileRead',
'data': { 'count': 'int', 'buf-b64': 'str', 'eof': 'bool' } }
##
# @guest-file-read:
#
# Read from an open file in the guest. Data will be base64-encoded
#
# @handle: filehandle returned by guest-file-open
#
# @count: #optional maximum number of bytes to read (default is 4KB)
#
# Returns: @GuestFileRead on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-read',
'data': { 'handle': 'int', '*count': 'int' },
'returns': 'GuestFileRead' }
##
# @GuestFileWrite
#
# Result of guest agent file-write operation
#
# @count: number of bytes written (note: count is actual bytes
# written, after base64-decoding of provided buffer)
#
# @eof: whether EOF was encountered during write operation.
#
# Since: 0.15.0
##
{ 'type': 'GuestFileWrite',
'data': { 'count': 'int', 'eof': 'bool' } }
##
# @guest-file-write:
#
# Write to an open file in the guest.
#
# @handle: filehandle returned by guest-file-open
#
# @buf-b64: base64-encoded string representing data to be written
#
# @count: #optional bytes to write (actual bytes, after base64-decode),
# default is all content in buf-b64 buffer after base64 decoding
#
# Returns: @GuestFileWrite on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-write',
'data': { 'handle': 'int', 'buf-b64': 'str', '*count': 'int' },
'returns': 'GuestFileWrite' }
##
# @GuestFileSeek
#
# Result of guest agent file-seek operation
#
# @position: current file position
#
# @eof: whether EOF was encountered during file seek
#
# Since: 0.15.0
##
{ 'type': 'GuestFileSeek',
'data': { 'position': 'int', 'eof': 'bool' } }
##
# @guest-file-seek:
#
# Seek to a position in the file, as with fseek(), and return the
# current file position afterward. Also encapsulates ftell()'s
# functionality, just Set offset=0, whence=SEEK_CUR.
#
# @handle: filehandle returned by guest-file-open
#
# @offset: bytes to skip over in the file stream
#
# @whence: SEEK_SET, SEEK_CUR, or SEEK_END, as with fseek()
#
# Returns: @GuestFileSeek on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-seek',
'data': { 'handle': 'int', 'offset': 'int', 'whence': 'int' },
'returns': 'GuestFileSeek' }
##
# @guest-file-flush:
#
# Write file changes bufferred in userspace to disk/kernel buffers
#
# @handle: filehandle returned by guest-file-open
#
# Returns: Nothing on success.
#
# Since: 0.15.0
##
{ 'command': 'guest-file-flush',
'data': { 'handle': 'int' } }
##
# @GuestFsFreezeStatus
#
# An enumation of filesystem freeze states
#
# @thawed: filesystems thawed/unfrozen
#
# @frozen: all non-network guest filesystems frozen
#
# @error: failure to thaw 1 or more
# previously frozen filesystems, or failure to open a previously
# cached filesytem (filesystem unmounted/directory changes, etc).
#
# Since: 0.15.0
##
{ 'enum': 'GuestFsfreezeStatus',
'data': [ 'thawed', 'frozen', 'error' ] }
##
# @guest-fsfreeze-status:
#
# Get guest fsfreeze state. error state indicates
#
# Returns: GuestFsfreezeStatus ("thawed", "frozen", etc., as defined below)
#
# Since: 0.15.0
##
{ 'command': 'guest-fsfreeze-status',
'returns': 'GuestFsfreezeStatus' }
##
# @guest-fsfreeze-freeze:
#
# Sync and freeze all non-network guest filesystems
#
# Returns: Number of file systems frozen on success
#
# Since: 0.15.0
##
{ 'command': 'guest-fsfreeze-freeze',
'returns': 'int' }
##
# @guest-fsfreeze-thaw:
#
# Unfreeze frozen guest fileystems
#
# Returns: Number of file systems thawed
# If error, -1 (unknown error) or -errno
#
# Since: 0.15.0
##
{ 'command': 'guest-fsfreeze-thaw',
'returns': 'int' }
##
# @guest-suspend-disk
#
# Suspend guest to disk.
#
# This command tries to execute the scripts provided by the pm-utils package.
# If it's not available, the suspend operation will be performed by manually
# writing to a sysfs file.
#
# For the best results it's strongly recommended to have the pm-utils
# package installed in the guest.
#
# Returns: nothing on success
# If suspend to disk is not supported, Unsupported
#
# Notes: o This is an asynchronous request. There's no guarantee a response
# will be sent
# o It's strongly recommended to issue the guest-sync command before
# sending commands when the guest resumes
#
# Since: 1.1
##
{ 'command': 'guest-suspend-disk' }
##
# @guest-suspend-ram
#
# Suspend guest to ram.
#
# This command tries to execute the scripts provided by the pm-utils package.
# If it's not available, the suspend operation will be performed by manually
# writing to a sysfs file.
#
# For the best results it's strongly recommended to have the pm-utils
# package installed in the guest.
#
# IMPORTANT: guest-suspend-ram requires QEMU to support the 'system_wakeup'
# command. Thus, it's *required* to query QEMU for the presence of the
# 'system_wakeup' command before issuing guest-suspend-ram.
#
# Returns: nothing on success
# If suspend to ram is not supported, Unsupported
#
# Notes: o This is an asynchronous request. There's no guarantee a response
# will be sent
# o It's strongly recommended to issue the guest-sync command before
# sending commands when the guest resumes
#
# Since: 1.1
##
{ 'command': 'guest-suspend-ram' }
##
# @guest-suspend-hybrid
#
# Save guest state to disk and suspend to ram.
#
# This command requires the pm-utils package to be installed in the guest.
#
# IMPORTANT: guest-suspend-hybrid requires QEMU to support the 'system_wakeup'
# command. Thus, it's *required* to query QEMU for the presence of the
# 'system_wakeup' command before issuing guest-suspend-hybrid.
#
# Returns: nothing on success
# If hybrid suspend is not supported, Unsupported
#
# Notes: o This is an asynchronous request. There's no guarantee a response
# will be sent
# o It's strongly recommended to issue the guest-sync command before
# sending commands when the guest resumes
#
# Since: 1.1
##
{ 'command': 'guest-suspend-hybrid' }
##
# @GuestIpAddressType:
#
# An enumeration of supported IP address types
#
# @ipv4: IP version 4
#
# @ipv6: IP version 6
#
# Since: 1.1
##
{ 'enum': 'GuestIpAddressType',
'data': [ 'ipv4', 'ipv6' ] }
##
# @GuestIpAddress:
#
# @ip-address: IP address
#
# @ip-address-type: Type of @ip-address (e.g. ipv4, ipv6)
#
# @prefix: Network prefix length of @ip-address
#
# Since: 1.1
##
{ 'type': 'GuestIpAddress',
'data': {'ip-address': 'str',
'ip-address-type': 'GuestIpAddressType',
'prefix': 'int'} }
##
# @GuestNetworkInterface:
#
# @name: The name of interface for which info are being delivered
#
# @hardware-address: Hardware address of @name
#
# @ip-addresses: List of addresses assigned to @name
#
# Since: 1.1
##
{ 'type': 'GuestNetworkInterface',
'data': {'name': 'str',
'*hardware-address': 'str',
'*ip-addresses': ['GuestIpAddress'] } }
##
# @guest-network-get-interfaces:
#
# Get list of guest IP addresses, MAC addresses
# and netmasks.
#
# Returns: List of GuestNetworkInfo on success.
#
# Since: 1.1
##
{ 'command': 'guest-network-get-interfaces',
'returns': ['GuestNetworkInterface'] }