From fccc998771043db1613509b26c18b3d7f071e668 Mon Sep 17 00:00:00 2001
From: Jiang Liu <liuj97@gmail.com>
Date: Wed, 3 Jul 2013 15:04:23 -0700
Subject: [PATCH] mm: introduce helper function set_max_mapnr()

Introduce a helper function set_max_mapnr() to set global variable
max_mapnr.

Also unify condition compilation for max_mapnr with
CONFIG_NEED_MULTIPLE_NODES instead of CONFIG_DISCONTIGMEM.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 include/linux/mm.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index e550a1773a9e..b87681adf0ba 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;