path: root/mm/memory.c
diff options
authorHugh Dickins <hugh.dickins@tiscali.co.uk>2009-09-21 17:03:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-22 07:17:40 -0700
commit2a15efc953b26ad57d7d38b9e6782d57e53b4ab2 (patch)
treef4d04903b3303e80460d2fa3f38da2b7eea82d22 /mm/memory.c
parentmm: FOLL_DUMP replace FOLL_ANON (diff)
mm: follow_hugetlb_page flags
follow_hugetlb_page() shouldn't be guessing about the coredump case either: pass the foll_flags down to it, instead of just the write bit. Remove that obscure huge_zeropage_ok() test. The decision is easy, though unlike the non-huge case - here vm_ops->fault is always set. But we know that a fault would serve up zeroes, unless there's already a hugetlbfs pagecache page to back the range. (Alternatively, since hugetlb pages aren't swapped out under pressure, you could save more dump space by arguing that a page not yet faulted into this process cannot be relevant to the dump; but that would be more surprising.) Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Acked-by: Rik van Riel <riel@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Minchan Kim <minchan.kim@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 8 insertions, 6 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 532a55bce6a4..6359a4f80c4a 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1260,17 +1260,19 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
!(vm_flags & vma->vm_flags))
return i ? : -EFAULT;
- if (is_vm_hugetlb_page(vma)) {
- i = follow_hugetlb_page(mm, vma, pages, vmas,
- &start, &nr_pages, i, write);
- continue;
- }
foll_flags = FOLL_TOUCH;
if (pages)
foll_flags |= FOLL_GET;
if (flags & GUP_FLAGS_DUMP)
foll_flags |= FOLL_DUMP;
+ if (write)
+ foll_flags |= FOLL_WRITE;
+ if (is_vm_hugetlb_page(vma)) {
+ i = follow_hugetlb_page(mm, vma, pages, vmas,
+ &start, &nr_pages, i, foll_flags);
+ continue;
+ }
do {
struct page *page;