qmp: add internal snapshot support in qmp_transaction

Unlike savevm, the qmp_transaction interface will not generate
snapshot name automatically, saving trouble to return information
of the new created snapshot.

Although qcow2 support storing multiple snapshots with same name
but different ID, here it will fail when an snapshot with that name
already exist before the operation. Format such as rbd do not support
ID at all, and in most case, it means trouble to user when he faces
multiple snapshots with same name, so ban that case. Request with
empty name will be rejected.

Snapshot ID can't be specified in this interface.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 18 insertions, 1 deletions

diff --git a/qapi-schema.json b/qapi-schema.json
index 2b2c8bce07..77bbbf59cf 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1686,6 +1686,22 @@
             '*mode': 'NewImageMode' } }
 
 ##
+# @BlockdevSnapshotInternal
+#
+# @device: the name of the device to generate the snapshot from
+#
+# @name: the name of the internal snapshot to be created
+#
+# Notes: In transaction, if @name is empty, or any snapshot matching @name
+#        exists, the operation will fail. Only some image formats support it,
+#        for example, qcow2, rbd, and sheepdog.
+#
+# Since: 1.7
+##
+{ 'type': 'BlockdevSnapshotInternal',
+  'data': { 'device': 'str', 'name': 'str' } }
+
+##
 # @DriveBackup
 #
 # @device: the name of the device which should be copied.
@@ -1747,7 +1763,8 @@
   'data': {
        'blockdev-snapshot-sync': 'BlockdevSnapshot',
        'drive-backup': 'DriveBackup',
-       'abort': 'Abort'
+       'abort': 'Abort',
+       'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal'
    } }
 
 ##