revert "s390/mm: change HPAGE_SHIFT type to int"

Heiko noticed that the current check for hugepage support on s390 is a
little bit too harsh as systems which do not support will crash.

The reason is that pageblock_order can now get negative when we set
HPAGE_SHIFT to 0.  To avoid all this and to avoid opening another can of
worms with enabling HUGETLB_PAGE_SIZE_VARIABLE I think it would be best
to simply allow architectures to define their own hugepages_supported().

This patch (of 4): revert commit cf54e2fce5 ("s390/mm: change
HPAGE_SHIFT type to int") in preparation.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dominik Dingel 2015-07-17 16:23:31 -07:00 committed by Linus Torvalds
parent 04ea1e91f8
commit ad4f99e888
2 changed files with 2 additions and 2 deletions

View File

@ -20,7 +20,7 @@
#include <asm/setup.h>
#ifndef __ASSEMBLY__
extern int HPAGE_SHIFT;
extern unsigned int HPAGE_SHIFT;
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)

View File

@ -31,7 +31,7 @@
#define ALLOC_ORDER 2
#define FRAG_MASK 0x03
int HPAGE_SHIFT;
unsigned int HPAGE_SHIFT;
unsigned long *crst_table_alloc(struct mm_struct *mm)
{