diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index d81a3659..2525691 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2620,6 +2620,8 @@
 		struct rb_entry **prev_entry, struct rb_entry **next_entry,
 		struct rb_node ***insert_p, struct rb_node **insert_parent,
 		bool force);
+bool __check_rb_tree_consistence(struct f2fs_sb_info *sbi,
+						struct rb_root *root);
 unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink);
 bool f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext);
 void f2fs_drop_extent_tree(struct inode *inode);