nommu: get_user_pages(): pin last page on non-page-aligned start

The noMMU version of get_user_pages() fails to pin the last page when the
start address isn't page-aligned.  The patch fixes this in a way that
makes find_extend_vma() congruent to its MMU cousin.

Signed-off-by: Steven J. Magnani <[email protected]>
Acked-by: Paul Mundt <[email protected]>
Cc: David Howells <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Steven J. Magnani 2010-03-05 13:42:24 -08:00 • committed by Linus Torvalds
commit c08c6e1f54

View file

@ -146,7 +146,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
(VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
for (i = 0; i < nr_pages; i++) {
vma = find_vma(mm, start);
vma = find_extend_vma(mm, start);
if (!vma)
goto finish_or_fault;
@ -764,7 +764,7 @@ EXPORT_SYMBOL(find_vma);
*/
struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
{
return find_vma(mm, addr);
return find_vma(mm, addr & PAGE_MASK);
}
/*