PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures

On 32-bit architectures PAGE_ALIGN() truncates 64-bit values to the 32-bit
boundary. For example:

	u64 val = PAGE_ALIGN(size);

always returns a value < 4GB even if size is greater than 4GB.

The problem resides in PAGE_MASK definition (from include/asm-x86/page.h for
example):

#define PAGE_SHIFT      12
#define PAGE_SIZE       (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK       (~(PAGE_SIZE-1))
...
#define PAGE_ALIGN(addr)       (((addr)+PAGE_SIZE-1)&PAGE_MASK)

The "~" is performed on a 32-bit value, so everything in "and" with
PAGE_MASK greater than 4GB will be truncated to the 32-bit boundary.
Using the ALIGN() macro seems to be the right way, because it uses
typeof(addr) for the mask.

Also move the PAGE_ALIGN() definitions out of include/asm-*/page.h in
include/linux/mm.h.

See also lkml discussion: http://lkml.org/lkml/2008/6/11/237

[akpm@linux-foundation.org: fix drivers/media/video/uvc/uvc_queue.c]
[akpm@linux-foundation.org: fix v850]
[akpm@linux-foundation.org: fix powerpc]
[akpm@linux-foundation.org: fix arm]
[akpm@linux-foundation.org: fix mips]
[akpm@linux-foundation.org: fix drivers/media/video/pvrusb2/pvrusb2-dvb.c]
[akpm@linux-foundation.org: fix drivers/mtd/maps/uclinux.c]
[akpm@linux-foundation.org: fix powerpc]
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 2 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-dvb.c b/drivers/media/video/pvrusb2/pvrusb2-dvb.c
index 6ec4bf81fc7f..77b3c3385066 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-dvb.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-dvb.c
@@ -20,6 +20,7 @@
 
 #include <linux/kthread.h>
 #include <linux/freezer.h>
+#include <linux/mm.h>
 #include "dvbdev.h"
 #include "pvrusb2-debug.h"
 #include "pvrusb2-hdw-internal.h"
diff --git a/drivers/media/video/pvrusb2/pvrusb2-ioread.c b/drivers/media/video/pvrusb2/pvrusb2-ioread.c
index 05a1376405e7..b4824782d858 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-ioread.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-ioread.c
@@ -22,6 +22,7 @@
 #include "pvrusb2-debug.h"
 #include <linux/errno.h>
 #include <linux/string.h>
+#include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <asm/uaccess.h>