mm: make read_cache_page synchronous
Ensure pages are uptodate after returning from read_cache_page, which allows
us to cut out most of the filesystem-internal PageUptodate calls.
I didn't have a great look down the call chains, but this appears to fixes 7
possible use-before uptodate in hfs, 2 in hfsplus, 1 in jfs, a few in
ecryptfs, 1 in jffs2, and a possible cleared data overwritten with readpage in
block2mtd. All depending on whether the filler is async and/or can return
with a !uptodate page.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index d69c459..dbbac55 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -236,8 +236,7 @@
err = PTR_ERR(page);
goto init_err_out;
}
- wait_on_page_locked(page);
- if (unlikely(!PageUptodate(page) || PageError(page))) {
+ if (unlikely(PageError(page))) {
page_cache_release(page);
err = -EIO;
goto init_err_out;