[PATCH 3/6] xfs/189: skip 'barrier' mount option test on newer kernels

["Darrick J. Wong" <darrick.wong@oracle.com>]

From: Darrick J. Wong <darrick.wong@oracle.com>

Starting in Linux 4.19 the 'barrier' and 'nobarrier' mount options were
removed.  If mount complains about a bad option when we remount with
'barrier', just skip the test.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 tests/xfs/189 |   14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)


diff --git a/tests/xfs/189 b/tests/xfs/189
index c1c52a22..2a2682ef 100755
--- a/tests/xfs/189
+++ b/tests/xfs/189
@@ -165,7 +165,19 @@ _test_remount_barrier()
 	echo
 
 	# mention barrier explicitly even if it's currently the default just to be sure
-	_try_scratch_mount -o barrier
+	_try_scratch_mount -o barrier > $tmp.barriermount 2>&1
+
+	# If the kernel doesn't recognize 'barrier' as a mount option then
+	# just fake the output.  The barrier option was removed in 4.19.
+	if grep -q "bad option" $tmp.barriermount; then
+		cat << ENDL
+SCRATCH_DEV on SCRATCH_MNT type xfs (rw)
+SCRATCH_DEV on SCRATCH_MNT type xfs (rw,nobarrier)
+SCRATCH_DEV on SCRATCH_MNT type xfs (rw)
+ENDL
+		return
+	fi
+
 	[ $? -eq 0 ] || echo "mount failed unexpectedly!"
 	_check_mount rw