From: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Snapshot-switch actually changes active state of disk so it should
reflect on dirty bitmaps. Otherwise next incremental backup using
these bitmaps will be invalid.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Message-id: 20171023092945.54532-1-vsement...@virtuozzo.com
Reviewed-by: Eric Blake <ebl...@redhat.com>
Reviewed-by: John Snow <js...@redhat.com>
Signed-off-by: Max Reitz <mre...@redhat.com>
---
block/snapshot.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/block/snapshot.c b/block/snapshot.c
index a46564e7b7..1d5ab5f90f 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -181,10 +181,24 @@ int bdrv_snapshot_goto(BlockDriverState *bs,
{
BlockDriver *drv = bs->drv;
int ret, open_ret;
+ int64_t len;
if (!drv) {
return -ENOMEDIUM;
}
+
+ len = bdrv_getlength(bs);
+ if (len < 0) {
+ return len;
+ }
+ /* We should set all bits in all enabled dirty bitmaps, because dirty
+ * bitmaps reflect active state of disk and snapshot switch operation
+ * actually dirties active state.
+ * TODO: It may make sense not to set all bits but analyze block status of
+ * current state and destination snapshot and do not set bits corresponding
+ * to both-zero or both-unallocated areas. */
+ bdrv_set_dirty(bs, 0, len);
+
if (drv->bdrv_snapshot_goto) {
return drv->bdrv_snapshot_goto(bs, snapshot_id);
}
--
2.13.6
