From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759843AbbJIAUE (ORCPT ); Thu, 8 Oct 2015 20:20:04 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35414 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758970AbbJIARc (ORCPT ); Thu, 8 Oct 2015 20:17:32 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Dave Chinner" , "David Jeffery" , "Dave Chinner" Date: Fri, 09 Oct 2015 01:12:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 054/107] xfs: return errors from partial I/O failures to files In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.247 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.72-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: David Jeffery commit c9eb256eda4420c06bb10f5e8fbdbe1a34bc98e0 upstream. There is an issue with xfs's error reporting in some cases of I/O partially failing and partially succeeding. Calls like fsync() can report success even though not all I/O was successful in partial-failure cases such as one disk of a RAID0 array being offline. The issue can occur when there are more than one bio per xfs_ioend struct. Each call to xfs_end_bio() for a bio completing will write a value to ioend->io_error. If a successful bio completes after any failed bio, no error is reported do to it writing 0 over the error code set by any failed bio. The I/O error information is now lost and when the ioend is completed only success is reported back up the filesystem stack. xfs_end_bio() should only set ioend->io_error in the case of BIO_UPTODATE being clear. ioend->io_error is initialized to 0 at allocation so only needs to be updated by a failed bio. Also check that ioend->io_error is 0 so that the first error reported will be the error code returned. Signed-off-by: David Jeffery Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- fs/xfs/xfs_aops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -365,7 +365,8 @@ xfs_end_bio( xfs_ioend_t *ioend = bio->bi_private; ASSERT(atomic_read(&bio->bi_cnt) >= 1); - ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error; + if (!ioend->io_error && !test_bit(BIO_UPTODATE, &bio->bi_flags)) + ioend->io_error = error; /* Toss bio and pass work off to an xfsdatad thread */ bio->bi_private = NULL;