Commit ca60ebfa authored Feb 21, 2013 by Jan Schmidt Committed by Josef Bacik Feb 26, 2013

Btrfs: fix backref walking race with tree deletions



When a subvolume is removed, we remove the root item from the root tree,
while the tree blocks and backrefs remain for a while. When backref walking
comes across one of those orphan tree blocks, it can find a backref for a
no longer existing root. This is all good, we only must tolerate
__resolve_indirect_ref returning an error and continue with the good refs
found.

Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

parent f2bdf9a8

fs/btrfs/backref.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -352,11 +352,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
		err = __resolve_indirect_ref(fs_info, search_commit_root,
		time_seq, ref, parents,
		extent_item_pos);
		if (err) {
		if (ret == 0)
		ret = err;
		if (err)
		continue;
		}

		/* we put the first parent into the ref at hand */
		ULIST_ITER_INIT(&uiter);