On 11/27/2015 02:06 PM, Wen Congyang wrote:
The new QMP command name is x-blockdev-change. It's just for adding/removing
quorum's child now, and doesn't support all kinds of children, all kinds of
operations, nor all block drivers. So it is experimental now.
Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
Signed-off-by: Gonglei <arei.gong...@huawei.com>
---
blockdev.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++
qapi/block-core.json | 23 ++++++++++++++++++++++
qmp-commands.hx | 47 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 124 insertions(+)
diff --git a/blockdev.c b/blockdev.c
index 2b076fb..7d8a2b4 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3836,6 +3836,60 @@ out:
aio_context_release(aio_context);
}
+static BlockDriverState *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->bs;
+ }
+ }
+
+ 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, *child_bs = NULL, *new_bs = NULL;
+
+ parent_bs = bdrv_lookup_bs(parent, parent, errp);
+ if (!parent_bs) {
+ return;
+ }
+
+ if (has_child == has_node) {
+ if (has_child) {
+ error_setg(errp, "The paramter child and node is conflict");
+ } else {
+ error_setg(errp, "Either child or node should be specified");
+ }
+ return;
+ }
+
+ if (has_child) {
+ child_bs = bdrv_find_child(parent_bs, child);
+ if (!child_bs) {
+ error_setg(errp, "Node '%s' doesn't have child %s",
+ parent, child);
+ return;
+ }
+ bdrv_del_child(parent_bs, child_bs, 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 a07b13f..feb8da2 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2400,3 +2400,26 @@
##
{ '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 block driver state. Currently only
+# the Quorum driver implements this feature to add or remove its child.
+# This is useful to fix a broken quorum child.
+#
+# @parent: the id or name of the node that will be changed.
+#
+# @child: #optional the name of the child that will be deleted.
+#
+# @node: #optional the name of the node will be added.
+#
+# Note: this command is experimental, and its API is not stable.
+#
+# Since: 2.6
+##
+{ 'command': 'x-blockdev-change',
+ 'data' : { 'parent': 'str',
+ '*child': 'str',
+ '*node': 'str' } }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 9d8b42f..9b49d51 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -4285,6 +4285,53 @@ 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 block driver state. Currently only
+the Quorum driver implements this feature to add and remove its child.
+This is useful to fix a broken quorum child.
+
+Arguments:
+- "parent": the id or node name of which node will be changed (json-string)
+- "child": the child name which will be deleted (json-string, optional)
+- "node": the new node-name which 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.
+
+Example:
+
+Add a new node to a quorum
+-> { "execute": blockdev-add",
miss a '"' before 'blockdev-add'
Thanks
Li
+ "arguments": { "options": { "driver": "raw",
+ "node-name": "new_node",
+ "id": "test_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.2" } }
+<- { "return": {} }
+
+EQMP
+
+ {
.name = "query-named-block-nodes",
.args_type = "",
.mhandler.cmd_new = qmp_marshal_query_named_block_nodes,
--
Best regards.
Li Zhijian (8555)
