btrfs: deal with errors when replaying dir entry during log replay

At replay_one_one(), we are treating any error returned from
btrfs_lookup_dir_item() or from btrfs_lookup_dir_index_item() as meaning
that there is no existing directory entry in the fs/subvolume tree.
This is not correct since we can get errors such as, for example, -EIO
when reading extent buffers while searching the fs/subvolume's btree.

So fix that and return the error to the caller when it is not -ENOENT.

CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/tree-log.c

@@ -1988,7 +1988,14 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans,
 		ret = -EINVAL;
 		goto out;
 	}
-	if (IS_ERR_OR_NULL(dst_di)) {
+
+	if (dst_di == ERR_PTR(-ENOENT))
+		dst_di = NULL;
+
+	if (IS_ERR(dst_di)) {
+		ret = PTR_ERR(dst_di);
+		goto out;
+	} else if (!dst_di) {
 		/* we need a sequence number to insert, so we only
 		 * do inserts for the BTRFS_DIR_INDEX_KEY types
 		 */