generic: check remount on I/O errors

XFS had a bug to hang on remount in this case, this kernel commit
fix the issue.

5cb13dc cancel the setfilesize transation when io error happen

Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

tests/generic/361

@@ -0,0 +1,78 @@
+#! /bin/bash
+# FS QA Test 361
+#
+# Test remount on I/O errors.
+#
+# XFS had a bug to hang on remount in this case, this kernel commit fix
+# the issue.
+# 5cb13dc cancel the setfilesize transation when io error happen
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2016 Red Hat Inc.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	$UMOUNT_PROG $fs_mnt
+	_destroy_loop_device $loop_dev
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs generic
+_supported_os Linux
+_require_scratch
+
+# create a small filesystem to hold another filesystem image
+_scratch_mkfs_sized $((512 * 1024 * 1024)) >>$seqres.full 2>&1
+_scratch_mount
+
+# create the sparse fs image and mount point
+fs_img=$SCRATCH_MNT/fs.img
+fs_mnt=$SCRATCH_MNT/mnt
+$XFS_IO_PROG -fc "truncate 1g" $fs_img >>$seqres.full 2>&1
+mkdir -p $fs_mnt
+
+# mount loop device and create a larger file to hit I/O errors on loop device
+loop_dev=$(_create_loop_device $fs_img)
+_mkfs_dev $loop_dev
+_mount $loop_dev $fs_mnt
+$XFS_IO_PROG -fc "pwrite 0 520m" $fs_mnt/testfile >>$seqres.full 2>&1
+
+# remount should not hang
+$MOUNT_PROG -o remount,ro $fs_mnt >>$seqres.full 2>&1
+
+# success, all done
+echo "Silence is golden"
+status=0
+exit

tests/generic/361.out

@@ -0,0 +1,2 @@
+QA output created by 361
+Silence is golden

tests/generic/group

@@ -363,3 +363,4 @@
 358 auto quick clone
 359 auto quick clone
 360 auto quick metadata
+361 auto quick