diff options
| author | Albert Herranz <albert_herranz@yahoo.es> | 2010-06-04 14:14:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-06-04 15:21:45 -0700 |
| commit | d6d03f9158516b50d0d343158e3f33bcff1e4ca5 (patch) | |
| tree | b853410433ef654e6a152804aa5dd2837cc0a2d7 | |
| parent | 3f505ca45735c35576dab4ceb3e3736d528b6672 (diff) | |
fb_defio: redo fix for non-dirty ptes
As pointed by Nick Piggin, ->page_mkwrite provides a way to keep a page
locked until the associated PTE is marked dirty.
Re-implement the fix by using this mechanism.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Acked-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/video/fb_defio.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c index 137100ea8ad7..6b93ef93cb12 100644 --- a/drivers/video/fb_defio.c +++ b/drivers/video/fb_defio.c @@ -100,6 +100,16 @@ static int fb_deferred_io_mkwrite(struct vm_area_struct *vma, /* protect against the workqueue changing the page list */ mutex_lock(&fbdefio->lock); + /* + * We want the page to remain locked from ->page_mkwrite until + * the PTE is marked dirty to avoid page_mkclean() being called + * before the PTE is updated, which would leave the page ignored + * by defio. + * Do this by locking the page here and informing the caller + * about it with VM_FAULT_LOCKED. + */ + lock_page(page); + /* we loop through the pagelist before adding in order to keep the pagelist sorted */ list_for_each_entry(cur, &fbdefio->pagelist, lru) { @@ -121,7 +131,7 @@ page_already_added: /* come back after delay to process the deferred IO */ schedule_delayed_work(&info->deferred_work, fbdefio->delay); - return 0; + return VM_FAULT_LOCKED; } static const struct vm_operations_struct fb_deferred_io_vm_ops = { |