path: root/mm/nommu.c
diff options
authorJie Zhang <jie.zhang@analog.com>2010-01-06 17:23:28 +0000
committerLinus Torvalds <torvalds@linux-foundation.org>2010-01-06 18:16:02 -0800
commit7959722b951cffcd61a0a35229d007deeed8c2dd (patch)
tree18badc77e7c79042c9321c279f9b47e8af3b36c5 /mm/nommu.c
parentcfe79c00a2f4f687eed8b7534d1d3d3d35540c29 (diff)
NOMMU: Use copy_*_user_page() in access_process_vm()
The MMU code uses the copy_*_user_page() variants in access_process_vm() rather than copy_*_user() as the former includes an icache flush. This is important when doing things like setting software breakpoints with gdb. So switch the NOMMU code over to do the same. This patch makes the reasonable assumption that copy_from_user_page() won't fail - which is probably fine, as we've checked the VMA from which we're copying is usable, and the copy is not allowed to cross VMAs. The one case where it might go wrong is if the VMA is a device rather than RAM, and that device returns an error which - in which case rubbish will be returned rather than EIO. Signed-off-by: Jie Zhang <jie.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: David McCullough <david_mccullough@mcafee.com> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/nommu.c')
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/nommu.c b/mm/nommu.c
index a8d17521624..17773862619 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1921,9 +1921,11 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in
/* only read or write mappings where it is permitted */
if (write && vma->vm_flags & VM_MAYWRITE)
- len -= copy_to_user((void *) addr, buf, len);
+ copy_to_user_page(vma, NULL, addr,
+ (void *) addr, buf, len);
else if (!write && vma->vm_flags & VM_MAYREAD)
- len -= copy_from_user(buf, (void *) addr, len);
+ copy_from_user_page(vma, NULL, addr,
+ buf, (void *) addr, len);
len = 0;
} else {