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>
Adrian Bunk reported that enabling 4MB page size breaks the build.
The problem is that MAX_ORDER combined with the page shift exceeds the
SECTION_SIZE_BITS we use in asm-sparc64/sparsemem.h
There are several ways I suppose we could work around this. For one
we could define a CONFIG_FORCE_MAX_ZONEORDER to decrease MAX_ORDER in
these higher page size cases.
But I also know that these page size cases are broken wrt. TLB miss
handling especially on pre-hypervisor systems, and there isn't an easy
way to fix that.
These options were meant to be fun experimental hacks anyways, and
only 8K and 64K make any sense to support.
So remove 512K and 4M base page size support. Of course, we still
support these page sizes for huge pages.
Signed-off-by: David S. Miller <davem@davemloft.net>
With this commit all sparc64 header files are moved to asm-sparc.
The remaining files (71 files) were too different to be trivially
merged so divide them up in a _32.h and a _64.h file which
are both included from the file with no bit size.
The following script were used:
cd include
FILES=`wc -l asm-sparc64/*h | grep -v '^ 1' | cut -b 20-`
for FILE in ${FILES}; do
echo $FILE:
BASE=`echo $FILE | cut -d '.' -f 1`
FN32=${BASE}_32.h
FN64=${BASE}_64.h
GUARD=___ASM_SPARC_`echo $BASE | tr '-' '_' | tr [:lower:] [:upper:]`_H
git mv asm-sparc/$FILE asm-sparc/$FN32
git mv asm-sparc64/$FILE asm-sparc/$FN64
echo git mv done
printf "#ifndef %s\n" $GUARD > asm-sparc/$FILE
printf "#define %s\n" $GUARD >> asm-sparc/$FILE
printf "#if defined(__sparc__) && defined(__arch64__)\n" >> asm-sparc/$FILE
printf "#include <asm-sparc/%s>\n" $FN64 >> asm-sparc/$FILE
printf "#else\n" >> asm-sparc/$FILE
printf "#include <asm-sparc/%s>\n" $FN32 >> asm-sparc/$FILE
printf "#endif\n" >> asm-sparc/$FILE
printf "#endif\n" >> asm-sparc/$FILE
git add asm-sparc/$FILE
echo new file done
printf "#include <asm-sparc/%s>\n" $FILE > asm-sparc64/$FILE
git add asm-sparc64/$FILE
echo sparc64 file done
done
The guard contains three '_' to avoid conflict with existing guards.
In additing the two Kbuild files are emptied to avoid breaking
headers_* targets.
We will reintroduce the exported header files when the necessary
kbuild changes are merged.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
