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linux-next/arch/m68k
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
..
amiga PAGE_ALIGN(): correctly handle 64-bit values on 32-bit architectures 2008-07-24 10:47:21 -07:00
apollo m68k: missing __init 2007-07-20 08:24:49 -07:00
atari m68k/atari/debug.c: possible cleanups 2008-07-20 17:24:39 -07:00
bvme6000 bvme6000-rtc: BKL pushdown 2008-06-20 14:05:55 -06:00
configs m68k: enable CONFIG_COMPAT_BRK by default 2008-06-06 11:29:09 -07:00
fpsp040 Stringify support commas 2008-07-20 17:24:38 -07:00
hp300 m68k: kill arch/m68k/hp300/ksyms.c 2008-02-05 09:44:23 -08:00
ifpsp060 Stringify support commas 2008-07-20 17:24:38 -07:00
kernel m68k/apollo: Add missing call to apollo_parse_bootinfo() 2008-07-20 17:24:40 -07:00
lib Stringify support commas 2008-07-20 17:24:38 -07:00
mac m68k/mac/: possible cleanups 2008-07-20 17:24:39 -07:00
math-emu Stringify support commas 2008-07-20 17:24:38 -07:00
mm mm: drop unneeded pgdat argument from free_area_init_node() 2008-07-24 10:47:16 -07:00
mvme16x mvme16x-rtc: BKL pushdown 2008-07-02 15:06:23 -06:00
mvme147 m68k: missing __init 2007-07-20 08:24:49 -07:00
q40 m68k/q40/config.c: make functions static 2008-07-20 17:24:39 -07:00
sun3 m68k/sun3/: possible cleanups 2008-07-20 17:24:39 -07:00
sun3x m68k: missing __init 2007-07-20 08:24:49 -07:00
tools/amiga Convert files to UTF-8 and some cleanups 2007-10-19 23:21:04 +02:00
Kconfig m68k/Atari: remove the dead ATARI_SCC{,_DMA} options 2008-07-20 17:24:40 -07:00
Kconfig.debug Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
Makefile m68k: make multi_defconfig the default defconfig 2008-07-20 17:24:38 -07:00