4.9-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 3.16.3 / __generic_file_write_iter-fix-handling-of-sync-error-after-dio.patch

From 60bb45297f7551833346c5cebc6d483ea17ea5f2 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 8 Aug 2014 12:39:16 -0400
Subject: __generic_file_write_iter(): fix handling of sync error after DIO

From: Al Viro <viro@zeniv.linux.org.uk>

commit 60bb45297f7551833346c5cebc6d483ea17ea5f2 upstream.

If DIO results in short write and sync write fails, we want to bugger off
whether the DIO part has written anything or not; the logics on the return
will take care of the right return value.

Reported-by: Anton Altaparmakov <aia21@cam.ac.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 mm/filemap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2584,7 +2584,7 @@ ssize_t __generic_file_write_iter(struct
 		 * that this differs from normal direct-io semantics, which
 		 * will return -EFOO even if some bytes were written.
 		 */
-		if (unlikely(status < 0) && !written) {
+		if (unlikely(status < 0)) {
 			err = status;
 			goto out;
 		}