From: Josef Bacik <jo...@toxicpanda.com>
commit c78a10aebb275c38d0cfccae129a803fe622e305 upstream.
When recovering a relocation, if we run into a reloc root that has 0
refs we simply add it to the reloc_control->reloc_roots list, and then
clean it up later. The problem with this is __del_reloc_root() doesn't
do anything if the root isn't in the radix tree, which in this case it
won't be because we never call __add_reloc_root() on the reloc_root.
This exit condition simply isn't correct really. During normal
operation we can remove ourselves from the rb tree and then we're meant
to clean up later at merge_reloc_roots() time, and this happens
correctly. During recovery we're depending on free_reloc_roots() to
drop our references, but we're short-circuiting.
Fix this by continuing to check if we're on the list and dropping
ourselves from the reloc_control root list and dropping our reference
appropriately. Change the corresponding BUG_ON() to an ASSERT() that
does the correct thing if we aren't in the rb tree.
CC: sta...@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <jo...@toxicpanda.com>
Reviewed-by: David Sterba <dste...@suse.com>
Signed-off-by: David Sterba <dste...@suse.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
fs/btrfs/relocation.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1335,9 +1335,7 @@ static void __del_reloc_root(struct btrf
RB_CLEAR_NODE(&node->rb_node);
}
spin_unlock(&rc->reloc_root_tree.lock);
- if (!node)
- return;
- BUG_ON((struct btrfs_root *)node->data != root);
+ ASSERT(!node || (struct btrfs_root *)node->data == root);
}
spin_lock(&root->fs_info->trans_lock);
