diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2017-03-02 15:26:18 +0100 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2017-03-07 14:53:28 +0100 |
| commit | 067acf28d1d726059f994356f25e054ce2926acf (patch) | |
| tree | 751726429485f8a66b96915dad5114c3ec5df27d /blockdev.c | |
| parent | 88f9d1b3d2fa8df276b2f75dcbd7fb78ed08be20 (diff) | |
block: Fix blockdev-snapshot error handling
For blockdev-snapshot, external_snapshot_prepare() accepts an arbitrary
node reference at first and only checks later whether it already has a
backing file. Between those places, other errors can occur.
Therefore checking in external_snapshot_abort() whether state->new_bs
has a backing file is not sufficient to tell whether bdrv_append() was
already completed or not. Trying to undo the bdrv_append() when it
wasn't even executed is wrong.
Introduce a new boolean flag in the state to fix this.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'blockdev.c')
| -rw-r--r-- | blockdev.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/blockdev.c b/blockdev.c index 8eb4e84fe0..af67ce4e56 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1614,6 +1614,7 @@ typedef struct ExternalSnapshotState { BlockDriverState *old_bs; BlockDriverState *new_bs; AioContext *aio_context; + bool overlay_appended; } ExternalSnapshotState; static void external_snapshot_prepare(BlkActionState *common, @@ -1780,6 +1781,7 @@ static void external_snapshot_prepare(BlkActionState *common, error_propagate(errp, local_err); return; } + state->overlay_appended = true; } static void external_snapshot_commit(BlkActionState *common) @@ -1803,7 +1805,7 @@ static void external_snapshot_abort(BlkActionState *common) ExternalSnapshotState *state = DO_UPCAST(ExternalSnapshotState, common, common); if (state->new_bs) { - if (state->new_bs->backing) { + if (state->overlay_appended) { bdrv_replace_in_backing_chain(state->new_bs, state->old_bs); } } |