path: root/include/asm-h8300
diff options
authorAndrea Righi <righi.andrea@gmail.com>2008-07-23 21:28:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-24 10:47:21 -0700
commit27ac792ca0b0a1e7e65f20342260650516c95864 (patch)
tree8e0bc93612da0803fe12303ccb75c837cd633c83 /include/asm-h8300
parentd92bc318547507a944a22e7ef936793dc0fe167f (diff)
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>
Diffstat (limited to 'include/asm-h8300')
1 files changed, 0 insertions, 3 deletions
diff --git a/include/asm-h8300/page.h b/include/asm-h8300/page.h
index d6a3eaf3b27..0b6acf0b03a 100644
--- a/include/asm-h8300/page.h
+++ b/include/asm-h8300/page.h
@@ -43,9 +43,6 @@ typedef struct page *pgtable_t;
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )
-/* to align the pointer to the (next) page boundary */
-#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)
extern unsigned long memory_start;
extern unsigned long memory_end;