diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 4e38a3d..83e432d 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -127,6 +127,7 @@
 	unsigned long map_start;
 	unsigned long map_len;
 	unsigned long bflags;
+	struct extent_io_tree *tree;
 	atomic_t refs;
 	atomic_t pages_reading;
 	struct list_head leak_list;