diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 0369f5b..eb663fb 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -6,6 +6,7 @@
  *  Copyright (C) 2010  Linus Torvalds
  */
 
+#include <linux/pagemap.h>
 #include <asm/tlb.h>
 #include <asm-generic/pgtable.h>