diff options
| author | Hugh Dickins <hugh.dickins@tiscali.co.uk> | 2009-09-21 17:03:27 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-22 07:17:40 -0700 |
| commit | 2a15efc953b26ad57d7d38b9e6782d57e53b4ab2 (patch) | |
| tree | f4d04903b3303e80460d2fa3f38da2b7eea82d22 /mm/memory.c | |
| parent | 8e4b9a60718970bbc02dfd3abd0b956ab65af231 (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 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/mm/memory.c b/mm/memory.c index 532a55bce6a..6359a4f80c4 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; |