+/*
+ * Search a cache_extent with same objectid, and covers start.
+ *
+ * If not found, return next if possible.
+ */
+struct cache_extent *search_cache_extent2(struct cache_tree *tree,
+ u64 objectid, u64 start);
+/*
+ * Search a cache_extent with same objectid, and covers the range
+ * [start, start + size)
+ *
+ * If not found, return next cache_extent if possible.
+ */
+struct cache_extent *lookup_cache_extent2(struct cache_tree *tree,
+ u64 objectid, u64 start, u64 size);
+int add_cache_extent2(struct cache_tree *tree,
+ u64 objectid, u64 start, u64 size);
+int insert_cache_extent2(struct cache_tree *tree, struct cache_extent *pe);
+
+/*
+ * Insert a cache_extent range [start, start + size).
+ *
+ * This function may merge with existing cache_extent.
+ * NOTE: caller must ensure the inserted range won't cover with any existing
+ * range.
+ */
+int add_merge_cache_extent(struct cache_tree *tree, u64 start, u64 size);