提交 a0031197 编写于 作者: M Michel Lespinasse 提交者: Linus Torvalds

mm: use vm_unmapped_area() on parisc architecture

Update the parisc arch_get_unmapped_area function to make use of
vm_unmapped_area() instead of implementing a brute force search.

[akpm@linux-foundation.org: remove now-unused DCACHE_ALIGN(), per James]
Signed-off-by: NMichel Lespinasse <walken@google.com>
Acked-by: NRik van Riel <riel@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Acked-by: NHelge Deller <deller@gmx.de>
Tested-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
上级 f7a3c997
......@@ -35,22 +35,17 @@
static unsigned long get_unshared_area(unsigned long addr, unsigned long len)
{
struct vm_area_struct *vma;
struct vm_unmapped_area_info info;
addr = PAGE_ALIGN(addr);
for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
/* At this point: (!vma || addr < vma->vm_end). */
if (TASK_SIZE - len < addr)
return -ENOMEM;
if (!vma || addr + len <= vma->vm_start)
return addr;
addr = vma->vm_end;
}
info.flags = 0;
info.length = len;
info.low_limit = PAGE_ALIGN(addr);
info.high_limit = TASK_SIZE;
info.align_mask = 0;
info.align_offset = 0;
return vm_unmapped_area(&info);
}
#define DCACHE_ALIGN(addr) (((addr) + (SHMLBA - 1)) &~ (SHMLBA - 1))
/*
* We need to know the offset to use. Old scheme was to look for
* existing mapping and use the same offset. New scheme is to use the
......@@ -63,30 +58,21 @@ static unsigned long get_unshared_area(unsigned long addr, unsigned long len)
*/
static int get_offset(struct address_space *mapping)
{
int offset = (unsigned long) mapping << (PAGE_SHIFT - 8);
return offset & 0x3FF000;
return (unsigned long) mapping >> 8;
}
static unsigned long get_shared_area(struct address_space *mapping,
unsigned long addr, unsigned long len, unsigned long pgoff)
{
struct vm_area_struct *vma;
int offset = mapping ? get_offset(mapping) : 0;
struct vm_unmapped_area_info info;
offset = (offset + (pgoff << PAGE_SHIFT)) & 0x3FF000;
addr = DCACHE_ALIGN(addr - offset) + offset;
for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
/* At this point: (!vma || addr < vma->vm_end). */
if (TASK_SIZE - len < addr)
return -ENOMEM;
if (!vma || addr + len <= vma->vm_start)
return addr;
addr = DCACHE_ALIGN(vma->vm_end - offset) + offset;
if (addr < vma->vm_end) /* handle wraparound */
return -ENOMEM;
}
info.flags = 0;
info.length = len;
info.low_limit = PAGE_ALIGN(addr);
info.high_limit = TASK_SIZE;
info.align_mask = PAGE_MASK & (SHMLBA - 1);
info.align_offset = (get_offset(mapping) + pgoff) << PAGE_SHIFT;
return vm_unmapped_area(&info);
}
unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
......
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