xfs: test that reflink forces the log if mounted with wsync

A code inspection revealed that reflink does not force the log to disk
even if the filesystem is mounted with wsync.  Add a regression test for
commit 5833112df7e9a ("xfs: reflink should force the log out if mounted
with wsync").

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

tests/xfs/914

@@ -0,0 +1,65 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (c) 2020, Oracle and/or its affiliates.  All Rights Reserved.
+#
+# FS QA Test No. 914
+#
+# Make sure that reflink forces the log out if we mount with wsync.  We test
+# that it actually forced the log by immediately shutting down the fs without
+# flushing the log and then remounting to check file contents.
+
+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()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/reflink
+
+# real QA test starts here
+_supported_fs xfs
+_supported_os Linux
+_require_scratch_reflink
+_require_cp_reflink
+
+rm -f $seqres.full
+
+# Format filesystem and set up quota limits
+_scratch_mkfs > $seqres.full
+_scratch_mount -o wsync >> $seqres.full
+
+# Set up initial files
+$XFS_IO_PROG -f -c 'pwrite -S 0x58 0 1m -b 1m' $SCRATCH_MNT/a >> $seqres.full
+$XFS_IO_PROG -f -c 'pwrite -S 0x59 0 1m -b 1m' $SCRATCH_MNT/c >> $seqres.full
+_cp_reflink $SCRATCH_MNT/a $SCRATCH_MNT/e
+_cp_reflink $SCRATCH_MNT/c $SCRATCH_MNT/d
+touch $SCRATCH_MNT/b
+sync
+
+# Test that setting the reflink flag on the dest file forces the log
+echo "test reflink flag not set"
+$XFS_IO_PROG -x -c "reflink $SCRATCH_MNT/a" -c 'shutdown' $SCRATCH_MNT/b >> $seqres.full
+_scratch_cycle_mount wsync
+md5sum $SCRATCH_MNT/a $SCRATCH_MNT/b | _filter_scratch
+
+# Test forcing the log even if both files are already reflinked
+echo "test reflink flag already set"
+$XFS_IO_PROG -x -c "reflink $SCRATCH_MNT/a" -c 'shutdown' $SCRATCH_MNT/d >> $seqres.full
+_scratch_cycle_mount wsync
+md5sum $SCRATCH_MNT/a $SCRATCH_MNT/d | _filter_scratch
+
+# success, all done
+status=0
+exit

tests/xfs/914.out

@@ -0,0 +1,7 @@
+QA output created by 914
+test reflink flag not set
+310f146ce52077fcd3308dcbe7632bb2  SCRATCH_MNT/a
+310f146ce52077fcd3308dcbe7632bb2  SCRATCH_MNT/b
+test reflink flag already set
+310f146ce52077fcd3308dcbe7632bb2  SCRATCH_MNT/a
+310f146ce52077fcd3308dcbe7632bb2  SCRATCH_MNT/d

tests/xfs/group

@@ -513,3 +513,4 @@
 513 auto mount
 514 auto quick db
 515 auto quick quota
+914 auto quick reflink