diff --git a/include/linux/mm.h b/include/linux/mm.h
index e550a1773a9e55941442b0dae98f7a647f01899b..b87681adf0bada78cec851382c7719a1c5e66945 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -25,8 +25,15 @@ struct file_ra_state;
 struct user_struct;
 struct writeback_control;
 
-#ifndef CONFIG_DISCONTIGMEM          /* Don't use mapnrs, do it properly */
+#ifndef CONFIG_NEED_MULTIPLE_NODES	/* Don't use mapnrs, do it properly */
 extern unsigned long max_mapnr;
+
+static inline void set_max_mapnr(unsigned long limit)
+{
+	max_mapnr = limit;
+}
+#else
+static inline void set_max_mapnr(unsigned long limit) { }
 #endif
 
 extern unsigned long totalram_pages;