From: Andrew Morton <akpm@linux-foundation.org>

modpost complains about missing swapper_space.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/block/rd.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN drivers/block/rd.c~rd-mark-ramdisk-buffer-heads-dirty-in-ramdisk_set_page_dirty-fix drivers/block/rd.c
--- a/drivers/block/rd.c~rd-mark-ramdisk-buffer-heads-dirty-in-ramdisk_set_page_dirty-fix
+++ a/drivers/block/rd.c
@@ -184,7 +184,7 @@ static int ramdisk_writepages(struct add
  */
 static int ramdisk_set_page_dirty(struct page *page)
 {
-	struct address_space * const mapping = page_mapping(page);
+	struct address_space * const mapping = page->mapping;
 
 	spin_lock(&mapping->private_lock);
 	if (page_has_buffers(page)) {
_