path: root/block.c
diff options
authorKevin Wolf <kwolf@redhat.com>2015-06-17 15:52:09 +0200
committerKevin Wolf <kwolf@redhat.com>2015-07-14 17:15:23 +0200
commit80a1e130917e0745625129553c943743eb663727 (patch)
tree7e77e913c49a4ba11a3ad67b0e8dffaa9e387de8 /block.c
parent9a7dedbc43c7c400663d2876a8ccb6d942a1429a (diff)
block: Fix backing file child when modifying graph
This patch moves bdrv_attach_child() from the individual places that add a backing file to a BDS to bdrv_set_backing_hd(), which is called by all of them. It also adds bdrv_detach_child() there. For normal operation (starting with one backing file chain and not changing it until the topmost image is closed) and live snapshots, this constitutes no change in behaviour. For all other cases, this is a fix for the bug that the old backing file was still referenced as a child, and the new one wasn't referenced. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block.c')
1 files changed, 3 insertions, 2 deletions
diff --git a/block.c b/block.c
index d5c9f032aa..d088ee02ff 100644
--- a/block.c
+++ b/block.c
@@ -1141,6 +1141,7 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
if (bs->backing_hd) {
bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
+ bdrv_detach_child(bs->backing_child);
} else if (backing_hd) {
"node is used as backing hd of '%s'",
@@ -1151,8 +1152,10 @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd)
if (!backing_hd) {
bs->backing_blocker = NULL;
+ bs->backing_child = NULL;
goto out;
+ bs->backing_child = bdrv_attach_child(bs, backing_hd, &child_backing);
bs->open_flags &= ~BDRV_O_NO_BACKING;
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
pstrcpy(bs->backing_format, sizeof(bs->backing_format),
@@ -1236,7 +1239,6 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
goto free_exit;
- bdrv_attach_child(bs, backing_hd, &child_backing);
bdrv_set_backing_hd(bs, backing_hd);
@@ -2171,7 +2173,6 @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
/* The contents of 'tmp' will become bs_top, as we are
* swapping bs_new and bs_top contents. */
bdrv_set_backing_hd(bs_top, bs_new);
- bdrv_attach_child(bs_top, bs_new, &child_backing);
static void bdrv_delete(BlockDriverState *bs)