btrfs: reduce parameters of btrfs_pin_reserved_extent

There is only one caller of btrfs_pin_reserved_extent that expands the
parameters to extent buffer members. We can simply pass the extent
buffer instead.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent-tree.c

@@ -4562,20 +4562,20 @@ int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
 	return 0;
 }
 
-int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start,
-			      u64 len)
+int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans,
+			      const struct extent_buffer *eb)
 {
 	struct btrfs_block_group *cache;
 	int ret = 0;
 
-	cache = btrfs_lookup_block_group(trans->fs_info, start);
+	cache = btrfs_lookup_block_group(trans->fs_info, eb->start);
 	if (!cache) {
 		btrfs_err(trans->fs_info, "unable to find block group for %llu",
-			  start);
+			  eb->start);
 		return -ENOSPC;
 	}
 
-	ret = pin_down_extent(trans, cache, start, len, 1);
+	ret = pin_down_extent(trans, cache, eb->start, eb->len, 1);
 	btrfs_put_block_group(cache);
 	return ret;
 }

fs/btrfs/extent-tree.h

@@ -139,7 +139,8 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_ref *ref);
 
 int btrfs_free_reserved_extent(struct btrfs_fs_info *fs_info,
 			       u64 start, u64 len, int delalloc);
-int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans, u64 start, u64 len);
+int btrfs_pin_reserved_extent(struct btrfs_trans_handle *trans,
+			      const struct extent_buffer *eb);
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans);
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_ref *generic_ref);
 int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref,

fs/btrfs/tree-log.c

@@ -2574,7 +2574,7 @@ static int clean_log_buffer(struct btrfs_trans_handle *trans,
 	btrfs_tree_unlock(eb);
 
 	if (trans) {
-		ret = btrfs_pin_reserved_extent(trans, eb->start, eb->len);
+		ret = btrfs_pin_reserved_extent(trans, eb);
 		if (ret)
 			return ret;
 		btrfs_redirty_list_add(trans->transaction, eb);