diff options
| -rw-r--r-- | blockdev.c | 55 | ||||
| -rw-r--r-- | qapi/block-core.json | 32 | ||||
| -rw-r--r-- | qmp-commands.hx | 53 |
3 files changed, 140 insertions, 0 deletions
diff --git a/blockdev.c b/blockdev.c index f74eb4357a..1892b8ec8e 100644 --- a/blockdev.c +++ b/blockdev.c @@ -4092,6 +4092,61 @@ out: aio_context_release(aio_context); } +static BdrvChild *bdrv_find_child(BlockDriverState *parent_bs, + const char *child_name) +{ + BdrvChild *child; + + QLIST_FOREACH(child, &parent_bs->children, next) { + if (strcmp(child->name, child_name) == 0) { + return child; + } + } + + return NULL; +} + +void qmp_x_blockdev_change(const char *parent, bool has_child, + const char *child, bool has_node, + const char *node, Error **errp) +{ + BlockDriverState *parent_bs, *new_bs = NULL; + BdrvChild *p_child; + + parent_bs = bdrv_lookup_bs(parent, parent, errp); + if (!parent_bs) { + return; + } + + if (has_child == has_node) { + if (has_child) { + error_setg(errp, "The parameters child and node are in conflict"); + } else { + error_setg(errp, "Either child or node must be specified"); + } + return; + } + + if (has_child) { + p_child = bdrv_find_child(parent_bs, child); + if (!p_child) { + error_setg(errp, "Node '%s' does not have child '%s'", + parent, child); + return; + } + bdrv_del_child(parent_bs, p_child, errp); + } + + if (has_node) { + new_bs = bdrv_find_node(node); + if (!new_bs) { + error_setg(errp, "Node '%s' not found", node); + return; + } + bdrv_add_child(parent_bs, new_bs, errp); + } +} + BlockJobInfoList *qmp_query_block_jobs(Error **errp) { BlockJobInfoList *head = NULL, **p_next = &head; diff --git a/qapi/block-core.json b/qapi/block-core.json index 1d09079cc1..98a20d22f4 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2556,3 +2556,35 @@ ## { 'command': 'block-set-write-threshold', 'data': { 'node-name': 'str', 'write-threshold': 'uint64' } } + +## +# @x-blockdev-change +# +# Dynamically reconfigure the block driver state graph. It can be used +# to add, remove, insert or replace a graph node. Currently only the +# Quorum driver implements this feature to add or remove its child. This +# is useful to fix a broken quorum child. +# +# If @node is specified, it will be inserted under @parent. @child +# may not be specified in this case. If both @parent and @child are +# specified but @node is not, @child will be detached from @parent. +# +# @parent: the id or name of the parent node. +# +# @child: #optional the name of a child under the given parent node. +# +# @node: #optional the name of the node that will be added. +# +# Note: this command is experimental, and its API is not stable. It +# does not support all kinds of operations, all kinds of children, nor +# all block drivers. +# +# Warning: The data in a new quorum child MUST be consistent with that of +# the rest of the array. +# +# Since: 2.7 +## +{ 'command': 'x-blockdev-change', + 'data' : { 'parent': 'str', + '*child': 'str', + '*node': 'str' } } diff --git a/qmp-commands.hx b/qmp-commands.hx index de896a5a31..94847e5b48 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -4398,6 +4398,59 @@ Example: EQMP { + .name = "x-blockdev-change", + .args_type = "parent:B,child:B?,node:B?", + .mhandler.cmd_new = qmp_marshal_x_blockdev_change, + }, + +SQMP +x-blockdev-change +----------------- + +Dynamically reconfigure the block driver state graph. It can be used +to add, remove, insert or replace a graph node. Currently only the +Quorum driver implements this feature to add or remove its child. This +is useful to fix a broken quorum child. + +If @node is specified, it will be inserted under @parent. @child +may not be specified in this case. If both @parent and @child are +specified but @node is not, @child will be detached from @parent. + +Arguments: +- "parent": the id or name of the parent node (json-string) +- "child": the name of a child under the given parent node (json-string, optional) +- "node": the name of the node that will be added (json-string, optional) + +Note: this command is experimental, and not a stable API. It doesn't +support all kinds of operations, all kinds of children, nor all block +drivers. + +Warning: The data in a new quorum child MUST be consistent with that of +the rest of the array. + +Example: + +Add a new node to a quorum +-> { "execute": "blockdev-add", + "arguments": { "options": { "driver": "raw", + "node-name": "new_node", + "file": { "driver": "file", + "filename": "test.raw" } } } } +<- { "return": {} } +-> { "execute": "x-blockdev-change", + "arguments": { "parent": "disk1", + "node": "new_node" } } +<- { "return": {} } + +Delete a quorum's node +-> { "execute": "x-blockdev-change", + "arguments": { "parent": "disk1", + "child": "children.1" } } +<- { "return": {} } + +EQMP + + { .name = "query-named-block-nodes", .args_type = "", .mhandler.cmd_new = qmp_marshal_query_named_block_nodes, |