Merge remote-tracking branch 'remotes/ericb/tags/pull-bitmaps-2021-02-12' into staging

bitmaps patches for 2021-02-12

- add 'transform' member to manipulate bitmaps across migration
- work towards better error handling during bdrv_open

# gpg: Signature made Fri 12 Feb 2021 23:19:39 GMT
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-bitmaps-2021-02-12:
  block: use return status of bdrv_append()
  block: return status from bdrv_append and friends
  qemu-iotests: 300: Add test case for modifying persistence of bitmap
  migration: dirty-bitmap: Allow control of bitmap persistence
  migration: dirty-bitmap: Use struct for alias map inner members

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/blockdev.c b/blockdev.c
index b250b9b959..cd438e60e3 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -1432,6 +1432,7 @@ typedef struct ExternalSnapshotState {
 static void external_snapshot_prepare(BlkActionState *common,
                                       Error **errp)
 {
+    int ret;
     int flags = 0;
     QDict *options = NULL;
     Error *local_err = NULL;
@@ -1591,9 +1592,8 @@ static void external_snapshot_prepare(BlkActionState *common,
      * can fail, so we need to do it in .prepare; undoing it for abort is
      * always possible. */
     bdrv_ref(state->new_bs);
-    bdrv_append(state->new_bs, state->old_bs, &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
+    ret = bdrv_append(state->new_bs, state->old_bs, errp);
+    if (ret < 0) {
         goto out;
     }
     state->overlay_appended = true;