From b522c94da5d9cbc73f708be5e530ebc3bbd4a031 Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Tue, 26 Oct 2010 14:21:56 -0700 Subject: mm: filemap_fault: unique path for locking page Introduce a single location where filemap_fault() locks the desired page. There used to be two such places, depending if the initial find_get_page() was successful or not. Signed-off-by: Michel Lespinasse Acked-by: Rik van Riel Acked-by: Linus Torvalds Cc: Nick Piggin Reviewed-by: Wu Fengguang Cc: Ying Han Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/filemap.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) (limited to 'mm/filemap.c') diff --git a/mm/filemap.c b/mm/filemap.c index 3d4df44e4221..8ed709a83eb7 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1539,25 +1539,27 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) * waiting for the lock. */ do_async_mmap_readahead(vma, ra, file, page, offset); - lock_page(page); - - /* Did it get truncated? */ - if (unlikely(page->mapping != mapping)) { - unlock_page(page); - put_page(page); - goto no_cached_page; - } } else { /* No page in the page cache at all */ do_sync_mmap_readahead(vma, ra, file, offset); count_vm_event(PGMAJFAULT); ret = VM_FAULT_MAJOR; retry_find: - page = find_lock_page(mapping, offset); + page = find_get_page(mapping, offset); if (!page) goto no_cached_page; } + lock_page(page); + + /* Did it get truncated? */ + if (unlikely(page->mapping != mapping)) { + unlock_page(page); + put_page(page); + goto retry_find; + } + VM_BUG_ON(page->index != offset); + /* * We have a locked page in the page cache, now we need to check * that it's up-to-date. If not, it is going to be due to an error. -- cgit v1.2.3-59-g8ed1b