btrfs: Don't BUG_ON errors from update_ref_for_cow()
__btrfs_cow_block(), the only caller of update_ref_for_cow() will BUG_ON()
any error return. Instead, we can go read-only fs as update_ref_for_cow()
manipulates disk data in a way which doesn't look like it's easily rolled
back.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 3b767d2..36e16bd 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -474,7 +474,10 @@
BTRFS_FSID_SIZE);
ret = update_ref_for_cow(trans, root, buf, cow, &last_ref);
- BUG_ON(ret);
+ if (ret) {
+ btrfs_std_error(root->fs_info, ret);
+ return ret;
+ }
if (root->ref_cows)
btrfs_reloc_cow_block(trans, root, buf, cow);