diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
new file mode 100644
index 0000000..ee95fa0
--- /dev/null
+++ b/fs/btrfs/disk-io.h
@@ -0,0 +1,21 @@
+#ifndef __DISKIO__
+#define __DISKIO__
+
+struct tree_buffer {
+	u64 blocknr;
+	int count;
+	union {
+		struct node node;
+		struct leaf leaf;
+	};
+};
+
+struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr);
+int write_tree_block(struct ctree_root *root, struct tree_buffer *buf);
+struct ctree_root *open_ctree(char *filename);
+int close_ctree(struct ctree_root *root);
+void tree_block_release(struct ctree_root *root, struct tree_buffer *buf);
+struct tree_buffer *alloc_free_block(struct ctree_root *root);
+int update_root_block(struct ctree_root *root);
+
+#endif