[PATCH] mm: make __put_page internal

Remove __put_page from outside the core mm/.  It is dangerous because it does
not handle compound pages nicely, and misses 1->0 transitions.  If a user
later appears that really needs the extra speed we can reevaluate.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 15 insertions, 0 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 44da3d476994..e8f58f7dd7a5 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -30,6 +30,8 @@
 #include <linux/security.h>
 #include <linux/syscalls.h>
 #include "filemap.h"
+#include "internal.h"
+
 /*
  * FIXME: remove all knowledge of the buffer layer from the core VM
  */
diff --git a/mm/internal.h b/mm/internal.h
index 17256bb2f4ef..e3042db2a2d6 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -8,6 +8,10 @@
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
+#ifndef __MM_INTERNAL_H
+#define __MM_INTERNAL_H
+
+#include <linux/mm.h>
 
 static inline void set_page_refs(struct page *page, int order)
 {
@@ -26,5 +30,12 @@ static inline void set_page_refs(struct page *page, int order)
 #endif /* CONFIG_MMU */
 }
 
+static inline void __put_page(struct page *page)
+{
+        atomic_dec(&page->_count);
+}
+
 extern void fastcall __init __free_pages_bootmem(struct page *page,
                                                 unsigned int order);
+
+#endif
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 486184d2b50c..3914a94aa905 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -39,6 +39,8 @@
 
 #include <linux/swapops.h>
 
+#include "internal.h"
+
 /* possible outcome of pageout() */
 typedef enum {
         /* failed to write page out, page is locked */