btrfs: fix insert_reserved error handling

commit 80ee54bfe8a3850015585ebc84e8d207fcae6831 upstream.

We were not handling the reserved byte accounting properly for data
references.  Metadata was fine, if it errored out the error paths would
free the bytes_reserved count and pin the extent, but it even missed one
of the error cases.  So instead move this handling up into
run_one_delayed_ref so we are sure that both cases are properly cleaned
up in case of a transaction abort.

CC: stable@vger.kernel.org # 4.18+
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/btrfs/extent-tree.c

@@ -2366,6 +2366,9 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
 					   insert_reserved);
 	else
 		BUG();
+	if (ret && insert_reserved)
+		btrfs_pin_extent(trans->fs_info, node->bytenr,
+				 node->num_bytes, 1);
 	return ret;
 }
 
@@ -7977,21 +7980,14 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 	}
 
 	path = btrfs_alloc_path();
-	if (!path) {
-		btrfs_free_and_pin_reserved_extent(fs_info,
-						   extent_key.objectid,
-						   fs_info->nodesize);
+	if (!path)
 		return -ENOMEM;
-	}
 
 	path->leave_spinning = 1;
 	ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
 				      &extent_key, size);
 	if (ret) {
 		btrfs_free_path(path);
-		btrfs_free_and_pin_reserved_extent(fs_info,
-						   extent_key.objectid,
-						   fs_info->nodesize);
 		return ret;
 	}