mirror of
https://github.com/torvalds/linux.git
synced 2024-11-01 01:31:44 +00:00
27ac792ca0
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>
93 lines
2.3 KiB
C
93 lines
2.3 KiB
C
/*
|
|
* Copyright (C) 2004-2006 Atmel Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/module.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
#include <asm/addrspace.h>
|
|
|
|
/*
|
|
* Re-map an arbitrary physical address space into the kernel virtual
|
|
* address space. Needed when the kernel wants to access physical
|
|
* memory directly.
|
|
*/
|
|
void __iomem *__ioremap(unsigned long phys_addr, size_t size,
|
|
unsigned long flags)
|
|
{
|
|
unsigned long addr;
|
|
struct vm_struct *area;
|
|
unsigned long offset, last_addr;
|
|
pgprot_t prot;
|
|
|
|
/*
|
|
* Check if we can simply use the P4 segment. This area is
|
|
* uncacheable, so if caching/buffering is requested, we can't
|
|
* use it.
|
|
*/
|
|
if ((phys_addr >= P4SEG) && (flags == 0))
|
|
return (void __iomem *)phys_addr;
|
|
|
|
/* Don't allow wraparound or zero size */
|
|
last_addr = phys_addr + size - 1;
|
|
if (!size || last_addr < phys_addr)
|
|
return NULL;
|
|
|
|
/*
|
|
* XXX: When mapping regular RAM, we'd better make damn sure
|
|
* it's never used for anything else. But this is really the
|
|
* caller's responsibility...
|
|
*/
|
|
if (PHYSADDR(P2SEGADDR(phys_addr)) == phys_addr)
|
|
return (void __iomem *)P2SEGADDR(phys_addr);
|
|
|
|
/* Mappings have to be page-aligned */
|
|
offset = phys_addr & ~PAGE_MASK;
|
|
phys_addr &= PAGE_MASK;
|
|
size = PAGE_ALIGN(last_addr + 1) - phys_addr;
|
|
|
|
prot = __pgprot(_PAGE_PRESENT | _PAGE_GLOBAL | _PAGE_RW | _PAGE_DIRTY
|
|
| _PAGE_ACCESSED | _PAGE_TYPE_SMALL | flags);
|
|
|
|
/*
|
|
* Ok, go for it..
|
|
*/
|
|
area = get_vm_area(size, VM_IOREMAP);
|
|
if (!area)
|
|
return NULL;
|
|
area->phys_addr = phys_addr;
|
|
addr = (unsigned long )area->addr;
|
|
if (ioremap_page_range(addr, addr + size, phys_addr, prot)) {
|
|
vunmap((void *)addr);
|
|
return NULL;
|
|
}
|
|
|
|
return (void __iomem *)(offset + (char *)addr);
|
|
}
|
|
EXPORT_SYMBOL(__ioremap);
|
|
|
|
void __iounmap(void __iomem *addr)
|
|
{
|
|
struct vm_struct *p;
|
|
|
|
if ((unsigned long)addr >= P4SEG)
|
|
return;
|
|
if (PXSEG(addr) == P2SEG)
|
|
return;
|
|
|
|
p = remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr));
|
|
if (unlikely(!p)) {
|
|
printk (KERN_ERR "iounmap: bad address %p\n", addr);
|
|
return;
|
|
}
|
|
|
|
kfree (p);
|
|
}
|
|
EXPORT_SYMBOL(__iounmap);
|