diff mbox

[v6,08/12] blockdev: allow BdrvActionOps->commit() to be NULL

Message ID 1372086800-4720-9-git-send-email-stefanha@redhat.com
State New
Headers show

Commit Message

Stefan Hajnoczi June 24, 2013, 3:13 p.m. UTC 
Some QMP 'transaction' types don't need to do anything on .commit().
Make .commit() optional just like .abort().

The "drive-backup" action will take advantage of this, it only needs to
cancel the block job on .abort().  Other block job actions will probably
follow the same pattern, so allow .commit() to be NULL.

Suggested-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 blockdev.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/blockdev.c b/blockdev.c
index a39cea4..8dc6f2e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -789,7 +789,7 @@  typedef struct BdrvActionOps {
     size_t instance_size;
     /* Prepare the work, must NOT be NULL. */
     void (*prepare)(BlkTransactionState *common, Error **errp);
-    /* Commit the changes, must NOT be NULL. */
+    /* Commit the changes, can be NULL. */
     void (*commit)(BlkTransactionState *common);
     /* Abort the changes on fail, can be NULL. */
     void (*abort)(BlkTransactionState *common);
@@ -969,7 +969,9 @@  void qmp_transaction(TransactionActionList *dev_list, Error **errp)
     }
 
     QSIMPLEQ_FOREACH(state, &snap_bdrv_states, entry) {
-        state->ops->commit(state);
+        if (state->ops->commit) {
+            state->ops->commit(state);
+        }
     }
 
     /* success */