kernel-ark/include/asm-s390/page.h
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

156 lines
4.2 KiB
C

/*
* include/asm-s390/page.h
*
* S390 version
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com)
*/
#ifndef _S390_PAGE_H
#define _S390_PAGE_H
#include <linux/const.h>
#include <asm/types.h>
/* PAGE_SHIFT determines the page size */
#define PAGE_SHIFT 12
#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
#define PAGE_DEFAULT_ACC 0
#define PAGE_DEFAULT_KEY (PAGE_DEFAULT_ACC << 4)
#define HPAGE_SHIFT 20
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
#define ARCH_HAS_SETCLEAR_HUGE_PTE
#define ARCH_HAS_HUGE_PTE_TYPE
#define ARCH_HAS_PREPARE_HUGEPAGE
#define ARCH_HAS_HUGEPAGE_CLEAR_FLUSH
#include <asm/setup.h>
#ifndef __ASSEMBLY__
static inline void clear_page(void *page)
{
if (MACHINE_HAS_PFMF) {
asm volatile(
" .insn rre,0xb9af0000,%0,%1"
: : "d" (0x10000), "a" (page) : "memory", "cc");
} else {
register unsigned long reg1 asm ("1") = 0;
register void *reg2 asm ("2") = page;
register unsigned long reg3 asm ("3") = 4096;
asm volatile(
" mvcl 2,0"
: "+d" (reg2), "+d" (reg3) : "d" (reg1)
: "memory", "cc");
}
}
static inline void copy_page(void *to, void *from)
{
if (MACHINE_HAS_MVPG) {
register unsigned long reg0 asm ("0") = 0;
asm volatile(
" mvpg %0,%1"
: : "a" (to), "a" (from), "d" (reg0)
: "memory", "cc");
} else
asm volatile(
" mvc 0(256,%0),0(%1)\n"
" mvc 256(256,%0),256(%1)\n"
" mvc 512(256,%0),512(%1)\n"
" mvc 768(256,%0),768(%1)\n"
" mvc 1024(256,%0),1024(%1)\n"
" mvc 1280(256,%0),1280(%1)\n"
" mvc 1536(256,%0),1536(%1)\n"
" mvc 1792(256,%0),1792(%1)\n"
" mvc 2048(256,%0),2048(%1)\n"
" mvc 2304(256,%0),2304(%1)\n"
" mvc 2560(256,%0),2560(%1)\n"
" mvc 2816(256,%0),2816(%1)\n"
" mvc 3072(256,%0),3072(%1)\n"
" mvc 3328(256,%0),3328(%1)\n"
" mvc 3584(256,%0),3584(%1)\n"
" mvc 3840(256,%0),3840(%1)\n"
: : "a" (to), "a" (from) : "memory");
}
#define clear_user_page(page, vaddr, pg) clear_page(page)
#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
#define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
#define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
/*
* These are used to make use of C type-checking..
*/
typedef struct { unsigned long pgprot; } pgprot_t;
typedef struct { unsigned long pte; } pte_t;
typedef struct { unsigned long pmd; } pmd_t;
typedef struct { unsigned long pud; } pud_t;
typedef struct { unsigned long pgd; } pgd_t;
typedef pte_t *pgtable_t;
#define pgprot_val(x) ((x).pgprot)
#define pte_val(x) ((x).pte)
#define pmd_val(x) ((x).pmd)
#define pud_val(x) ((x).pud)
#define pgd_val(x) ((x).pgd)
#define __pte(x) ((pte_t) { (x) } )
#define __pmd(x) ((pmd_t) { (x) } )
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )
/* default storage key used for all pages */
extern unsigned int default_storage_key;
static inline void
page_set_storage_key(unsigned long addr, unsigned int skey)
{
asm volatile("sske %0,%1" : : "d" (skey), "a" (addr));
}
static inline unsigned int
page_get_storage_key(unsigned long addr)
{
unsigned int skey;
asm volatile("iske %0,%1" : "=d" (skey) : "a" (addr), "0" (0));
return skey;
}
#ifdef CONFIG_PAGE_STATES
struct page;
void arch_free_page(struct page *page, int order);
void arch_alloc_page(struct page *page, int order);
#define HAVE_ARCH_FREE_PAGE
#define HAVE_ARCH_ALLOC_PAGE
#endif
#endif /* !__ASSEMBLY__ */
#define __PAGE_OFFSET 0x0UL
#define PAGE_OFFSET 0x0UL
#define __pa(x) (unsigned long)(x)
#define __va(x) (void *)(unsigned long)(x)
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#include <asm-generic/memory_model.h>
#include <asm-generic/page.h>
#endif /* _S390_PAGE_H */