btrfs: get fs_info from trans in create_free_space_inode

We can read fs_info from the transaction and can drop it from the
parameters.
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent-tree.c

@@ -3411,8 +3411,7 @@ static int cache_save_setup(struct btrfs_block_group_cache *block_group,
 		if (block_group->ro)
 			goto out_free;
 
-		ret = create_free_space_inode(fs_info, trans, block_group,
-					      path);
+		ret = create_free_space_inode(trans, block_group, path);
 		if (ret)
 			goto out_free;
 		goto again;

fs/btrfs/free-space-cache.c

@@ -185,20 +185,19 @@ static int __create_free_space_inode(struct btrfs_root *root,
 	return 0;
 }
 
-int create_free_space_inode(struct btrfs_fs_info *fs_info,
-			    struct btrfs_trans_handle *trans,
+int create_free_space_inode(struct btrfs_trans_handle *trans,
 			    struct btrfs_block_group_cache *block_group,
 			    struct btrfs_path *path)
 {
 	int ret;
 	u64 ino;
 
-	ret = btrfs_find_free_objectid(fs_info->tree_root, &ino);
+	ret = btrfs_find_free_objectid(trans->fs_info->tree_root, &ino);
 	if (ret < 0)
 		return ret;
 
-	return __create_free_space_inode(fs_info->tree_root, trans, path, ino,
-					 block_group->key.objectid);
+	return __create_free_space_inode(trans->fs_info->tree_root, trans, path,
+					 ino, block_group->key.objectid);
 }
 
 int btrfs_check_trunc_cache_free_space(struct btrfs_fs_info *fs_info,

fs/btrfs/free-space-cache.h

@@ -41,8 +41,7 @@ struct btrfs_io_ctl;
 struct inode *lookup_free_space_inode(struct btrfs_fs_info *fs_info,
 				      struct btrfs_block_group_cache
 				      *block_group, struct btrfs_path *path);
-int create_free_space_inode(struct btrfs_fs_info *fs_info,
-			    struct btrfs_trans_handle *trans,
+int create_free_space_inode(struct btrfs_trans_handle *trans,
 			    struct btrfs_block_group_cache *block_group,
 			    struct btrfs_path *path);