Btrfs: cleanup reloc roots properly on error
I was hitting the BUG_ON() at the end of merge_reloc_roots() because we were
aborting the transaction at some point previously and then getting an error when
we tried to drop the reloc root. I fixed btrfs_drop_snapshot to re-add us to
the dead roots list if we failed, but this isn't the right thing to do for reloc
roots since it uses root->root_list for it's own stuff in order to know what
needs to be cleaned up. So fix btrfs_drop_snapshot to only do the re-add if we
aren't dropping for reloc, and handle errors from merge_reloc_root() by dropping
the reloc root we are processing since it won't be on the list of roots to
cleanup. With this patch my reproducer no longer panics. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index ca02d3c..e868c35 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -7696,7 +7696,7 @@
* don't have it in the radix (like when we recover after a power fail
* or unmount) so we don't leak memory.
*/
- if (root_dropped == false)
+ if (!for_reloc && root_dropped == false)
btrfs_add_dead_root(root);
if (err)
btrfs_std_error(root->fs_info, err);