memcg: make memcg's file mapped consistent with global VM

In global VM, FILE_MAPPED is used but memcg uses MAPPED_FILE.  This makes
grep difficult.  Replace memcg's MAPPED_FILE with FILE_MAPPED

And in global VM, mapped shared memory is accounted into FILE_MAPPED.
But memcg doesn't. fix it.
Note:
  page_is_file_cache() just checks SwapBacked or not.
  So, we need to check PageAnon.

Cc: Balbir Singh <balbir@in.ibm.com>
Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 91300c9..0b46c20 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -122,7 +122,7 @@
 }
 
 extern bool mem_cgroup_oom_called(struct task_struct *task);
-void mem_cgroup_update_mapped_file_stat(struct page *page, int val);
+void mem_cgroup_update_file_mapped(struct page *page, int val);
 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
 						gfp_t gfp_mask, int nid,
 						int zid);
@@ -287,7 +287,7 @@
 {
 }
 
-static inline void mem_cgroup_update_mapped_file_stat(struct page *page,
+static inline void mem_cgroup_update_file_mapped(struct page *page,
 							int val)
 {
 }