From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from youngberry.canonical.com ([91.189.89.112]:43040 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753270AbbJTVgU (ORCPT ); Tue, 20 Oct 2015 17:36:20 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: David Jeffery , Dave Chinner , Luis Henriques , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 48/85] xfs: return errors from partial I/O failures to files Date: Tue, 20 Oct 2015 14:35:04 -0700 Message-Id: <1445376941-7046-49-git-send-email-kamal@canonical.com> In-Reply-To: <1445376941-7046-1-git-send-email-kamal@canonical.com> References: <1445376941-7046-1-git-send-email-kamal@canonical.com> Sender: stable-owner@vger.kernel.org List-ID: 3.13.11-ckt28 -stable 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 [ luis: backported to 3.16: adjusted context ] Signed-off-by: Luis Henriques Signed-off-by: Kamal Mostafa --- fs/xfs/xfs_aops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index e752236..ebc3107 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -377,7 +377,8 @@ 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; -- 1.9.1