| Message ID | 1378695482-29805-3-git-send-email-xiawenc@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
On 09/08/2013 08:57 PM, Wenchao Xia wrote: > Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> > --- > block/qcow2-snapshot.c | 7 +++++-- > 1 files changed, 5 insertions(+), 2 deletions(-) Reviewed-by: Eric Blake <eblake@redhat.com>
On Mon, Sep 09, 2013 at 10:57:57AM +0800, Wenchao Xia wrote: > Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> > --- > block/qcow2-snapshot.c | 7 +++++-- > 1 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c > index 40393b2..9e2d695 100644 > --- a/block/qcow2-snapshot.c > +++ b/block/qcow2-snapshot.c > @@ -186,7 +186,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs) > } > ret = bdrv_flush(bs); > if (ret < 0) { > - return ret; > + goto fail; > } > > /* The snapshot list position has not yet been updated, so these clusters > @@ -194,7 +194,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs) > ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, offset, > s->snapshots_size); > if (ret < 0) { > - return ret; > + goto fail; > } > > > @@ -278,6 +278,9 @@ static int qcow2_write_snapshots(BlockDriverState *bs) > return 0; > > fail: > + /* free the new snapshot table */ > + qcow2_free_clusters(bs, snapshots_offset, snapshots_size, > + QCOW2_DISCARD_ALWAYS); It is safer to skip qcow2_free_clusters() when the final bdrv_pwrite_sync() fails. We don't know if the header was updated on disk. If it was updated, then freeing the clusters may allow them to be reallocated later (this will cause corruption).
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 40393b2..9e2d695 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -186,7 +186,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs) } ret = bdrv_flush(bs); if (ret < 0) { - return ret; + goto fail; } /* The snapshot list position has not yet been updated, so these clusters @@ -194,7 +194,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs) ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, offset, s->snapshots_size); if (ret < 0) { - return ret; + goto fail; } @@ -278,6 +278,9 @@ static int qcow2_write_snapshots(BlockDriverState *bs) return 0; fail: + /* free the new snapshot table */ + qcow2_free_clusters(bs, snapshots_offset, snapshots_size, + QCOW2_DISCARD_ALWAYS); return ret; }
Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> --- block/qcow2-snapshot.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-)