xref: /openbmc/qemu/qapi/yank.json (revision 51e47cf8) 
1# -*- Mode: Python -*-
2# vim: filetype=python
3#
4
5##
6# = Yank feature
7##
8
9##
10# @YankInstanceType:
11#
12# An enumeration of yank instance types.  See @YankInstance for more
13# information.
14#
15# Since: 6.0
16##
17{ 'enum': 'YankInstanceType',
18  'data': [ 'block-node', 'chardev', 'migration' ] }
19
20##
21# @YankInstanceBlockNode:
22#
23# Specifies which block graph node to yank.  See @YankInstance for
24# more information.
25#
26# @node-name: the name of the block graph node
27#
28# Since: 6.0
29##
30{ 'struct': 'YankInstanceBlockNode',
31  'data': { 'node-name': 'str' } }
32
33##
34# @YankInstanceChardev:
35#
36# Specifies which character device to yank.  See @YankInstance for
37# more information.
38#
39# @id: the chardev's ID
40#
41# Since: 6.0
42##
43{ 'struct': 'YankInstanceChardev',
44  'data': { 'id': 'str' } }
45
46##
47# @YankInstance:
48#
49# A yank instance can be yanked with the @yank qmp command to recover
50# from a hanging QEMU.
51#
52# Currently implemented yank instances:
53#
54# - nbd block device: Yanking it will shut down the connection to the
55#   nbd server without attempting to reconnect.
56# - socket chardev: Yanking it will shut down the connected socket.
57# - migration: Yanking it will shut down all migration connections.
58#   Unlike @migrate_cancel, it will not notify the migration process,
59#   so migration will go into @failed state, instead of @cancelled
60#   state.  @yank should be used to recover from hangs.
61#
62# Since: 6.0
63##
64{ 'union': 'YankInstance',
65  'base': { 'type': 'YankInstanceType' },
66  'discriminator': 'type',
67  'data': {
68      'block-node': 'YankInstanceBlockNode',
69      'chardev': 'YankInstanceChardev' } }
70
71##
72# @yank:
73#
74# Try to recover from hanging QEMU by yanking the specified instances.
75# See @YankInstance for more information.
76#
77# Takes a list of @YankInstance as argument.
78#
79# Returns:
80# - Nothing on success
81# - @DeviceNotFound error, if any of the YankInstances doesn't exist
82#
83# Example:
84#
85# -> { "execute": "yank",
86#      "arguments": {
87#          "instances": [
88#               { "type": "block-node",
89#                 "node-name": "nbd0" }
90#          ] } }
91# <- { "return": {} }
92#
93# Since: 6.0
94##
95{ 'command': 'yank',
96  'data': { 'instances': ['YankInstance'] },
97  'allow-oob': true }
98
99##
100# @query-yank:
101#
102# Query yank instances.  See @YankInstance for more information.
103#
104# Returns: list of @YankInstance
105#
106# Example:
107#
108# -> { "execute": "query-yank" }
109# <- { "return": [
110#          { "type": "block-node",
111#            "node-name": "nbd0" }
112#      ] }
113#
114# Since: 6.0
115##
116{ 'command': 'query-yank',
117  'returns': ['YankInstance'],
118  'allow-oob': true }
119