mm: madvise: fix MADV_WILLNEED on shmem swapouts

MADV_WILLNEED currently does not read swapped out shmem pages back in.

Commit 0cd6144aad ("mm + fs: prepare for non-page entries in page
cache radix trees") made find_get_page() filter exceptional radix tree
entries but failed to convert all find_get_page() callers that WANT
exceptional entries over to find_get_entry().  One of them is shmem swap
readahead in madvise, which now skips over any swap-out records.

Convert it to find_get_entry().

Fixes: 0cd6144aad ("mm + fs: prepare for non-page entries in page cache radix trees")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Johannes Weiner 2014-05-22 11:54:17 -07:00 committed by Linus Torvalds
parent 7fcbbaf183
commit 55231e5c89

View file

@ -195,7 +195,7 @@ static void force_shm_swapin_readahead(struct vm_area_struct *vma,
for (; start < end; start += PAGE_SIZE) {
index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
page = find_get_page(mapping, index);
page = find_get_entry(mapping, index);
if (!radix_tree_exceptional_entry(page)) {
if (page)
page_cache_release(page);