kernel-ark/include/asm-m68k/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

229 lines
5.3 KiB
C

#ifndef _M68K_PAGE_H
#define _M68K_PAGE_H
#include <linux/const.h>
/* PAGE_SHIFT determines the page size */
#ifndef CONFIG_SUN3
#define PAGE_SHIFT (12)
#else
#define PAGE_SHIFT (13)
#endif
#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
#include <asm/setup.h>
#if PAGE_SHIFT < 13
#define THREAD_SIZE (8192)
#else
#define THREAD_SIZE PAGE_SIZE
#endif
#ifndef __ASSEMBLY__
#include <linux/compiler.h>
#include <asm/module.h>
#define get_user_page(vaddr) __get_free_page(GFP_KERNEL)
#define free_user_page(page, addr) free_page(addr)
/*
* We don't need to check for alignment etc.
*/
#ifdef CPU_M68040_OR_M68060_ONLY
static inline void copy_page(void *to, void *from)
{
unsigned long tmp;
__asm__ __volatile__("1:\t"
".chip 68040\n\t"
"move16 %1@+,%0@+\n\t"
"move16 %1@+,%0@+\n\t"
".chip 68k\n\t"
"dbra %2,1b\n\t"
: "=a" (to), "=a" (from), "=d" (tmp)
: "0" (to), "1" (from) , "2" (PAGE_SIZE / 32 - 1)
);
}
static inline void clear_page(void *page)
{
unsigned long tmp;
unsigned long *sp = page;
*sp++ = 0;
*sp++ = 0;
*sp++ = 0;
*sp++ = 0;
__asm__ __volatile__("1:\t"
".chip 68040\n\t"
"move16 %2@+,%0@+\n\t"
".chip 68k\n\t"
"subqw #8,%2\n\t"
"subqw #8,%2\n\t"
"dbra %1,1b\n\t"
: "=a" (sp), "=d" (tmp)
: "a" (page), "0" (sp),
"1" ((PAGE_SIZE - 16) / 16 - 1));
}
#else
#define clear_page(page) memset((page), 0, PAGE_SIZE)
#define copy_page(to,from) memcpy((to), (from), PAGE_SIZE)
#endif
#define clear_user_page(addr, vaddr, page) \
do { clear_page(addr); \
flush_dcache_page(page); \
} while (0)
#define copy_user_page(to, from, vaddr, page) \
do { copy_page(to, from); \
flush_dcache_page(page); \
} while (0)
/*
* These are used to make use of C type-checking..
*/
typedef struct { unsigned long pte; } pte_t;
typedef struct { unsigned long pmd[16]; } pmd_t;
typedef struct { unsigned long pgd; } pgd_t;
typedef struct { unsigned long pgprot; } pgprot_t;
typedef struct page *pgtable_t;
#define pte_val(x) ((x).pte)
#define pmd_val(x) ((&x)->pmd[0])
#define pgd_val(x) ((x).pgd)
#define pgprot_val(x) ((x).pgprot)
#define __pte(x) ((pte_t) { (x) } )
#define __pmd(x) ((pmd_t) { (x) } )
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )
#endif /* !__ASSEMBLY__ */
#include <asm/page_offset.h>
#define PAGE_OFFSET (PAGE_OFFSET_RAW)
#ifndef __ASSEMBLY__
extern unsigned long m68k_memoffset;
#ifndef CONFIG_SUN3
#define WANT_PAGE_VIRTUAL
static inline unsigned long ___pa(void *vaddr)
{
unsigned long paddr;
asm (
"1: addl #0,%0\n"
m68k_fixup(%c2, 1b+2)
: "=r" (paddr)
: "0" (vaddr), "i" (m68k_fixup_memoffset));
return paddr;
}
#define __pa(vaddr) ___pa((void *)(vaddr))
static inline void *__va(unsigned long paddr)
{
void *vaddr;
asm (
"1: subl #0,%0\n"
m68k_fixup(%c2, 1b+2)
: "=r" (vaddr)
: "0" (paddr), "i" (m68k_fixup_memoffset));
return vaddr;
}
#else /* !CONFIG_SUN3 */
/* This #define is a horrible hack to suppress lots of warnings. --m */
#define __pa(x) ___pa((unsigned long)(x))
static inline unsigned long ___pa(unsigned long x)
{
if(x == 0)
return 0;
if(x >= PAGE_OFFSET)
return (x-PAGE_OFFSET);
else
return (x+0x2000000);
}
static inline void *__va(unsigned long x)
{
if(x == 0)
return (void *)0;
if(x < 0x2000000)
return (void *)(x+PAGE_OFFSET);
else
return (void *)(x-0x2000000);
}
#endif /* CONFIG_SUN3 */
/*
* NOTE: virtual isn't really correct, actually it should be the offset into the
* memory node, but we have no highmem, so that works for now.
* TODO: implement (fast) pfn<->pgdat_idx conversion functions, this makes lots
* of the shifts unnecessary.
*/
#define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
#define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT)
extern int m68k_virt_to_node_shift;
#ifdef CONFIG_SINGLE_MEMORY_CHUNK
#define __virt_to_node(addr) (&pg_data_map[0])
#else
extern struct pglist_data *pg_data_table[];
static inline __attribute_const__ int __virt_to_node_shift(void)
{
int shift;
asm (
"1: moveq #0,%0\n"
m68k_fixup(%c1, 1b)
: "=d" (shift)
: "i" (m68k_fixup_vnode_shift));
return shift;
}
#define __virt_to_node(addr) (pg_data_table[(unsigned long)(addr) >> __virt_to_node_shift()])
#endif
#define virt_to_page(addr) ({ \
pfn_to_page(virt_to_pfn(addr)); \
})
#define page_to_virt(page) ({ \
pfn_to_virt(page_to_pfn(page)); \
})
#define pfn_to_page(pfn) ({ \
unsigned long __pfn = (pfn); \
struct pglist_data *pgdat; \
pgdat = __virt_to_node((unsigned long)pfn_to_virt(__pfn)); \
pgdat->node_mem_map + (__pfn - pgdat->node_start_pfn); \
})
#define page_to_pfn(_page) ({ \
struct page *__p = (_page); \
struct pglist_data *pgdat; \
pgdat = &pg_data_map[page_to_nid(__p)]; \
((__p) - pgdat->node_mem_map) + pgdat->node_start_pfn; \
})
#define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory)
#define pfn_valid(pfn) virt_addr_valid(pfn_to_virt(pfn))
#endif /* __ASSEMBLY__ */
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#include <asm-generic/page.h>
#endif /* _M68K_PAGE_H */