diff --git a/fs/btrfs/accessors.h b/fs/btrfs/accessors.h
index 8cfc8214109c..f958eccff477 100644
--- a/fs/btrfs/accessors.h
+++ b/fs/btrfs/accessors.h
@@ -4,6 +4,7 @@
 #define BTRFS_ACCESSORS_H
 
 #include <linux/stddef.h>
+#include <asm/unaligned.h>
 
 struct btrfs_map_token {
 	struct extent_buffer *eb;