linux/arch/avr32
Andrea Righi 27ac792ca0 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>
2008-07-24 10:47:21 -07:00
..
boards atmel-mci: Driver for Atmel on-chip MMC controllers 2008-07-15 14:14:49 +02:00
boot [PATCH] AVR32: Minor Makefile cleanup 2006-10-25 20:26:32 -07:00
configs avr32: Update defconfigs 2008-05-26 13:38:29 +02:00
kernel sysdev: Pass the attribute to the low level sysdev show/store function 2008-07-21 21:55:02 -07:00
lib avr32: Fix wrong I/O access size in __raw_readsb 2008-06-27 15:07:50 +02:00
mach-at32ap Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2008-07-23 12:03:18 -07:00
mm PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures 2008-07-24 10:47:21 -07:00
oprofile avr32: Delete mostly unused header asm/intc.h 2008-04-19 20:40:07 -04:00
Kconfig add HAVE_CLK to Kconfig, for driver dependencies 2008-07-24 10:47:13 -07:00
Kconfig.debug [AVR32] Include instrumentation menu 2008-01-25 08:31:40 +01:00
Makefile [AVR32] Add support for AT32AP7001 and AT32AP7002 2008-01-25 08:31:41 +01:00