[PATCH] overlay/081: fix test when running with index enabled

[Amir Goldstein <amir73il@gmail.com>]

Test overlay/081 fails with:
 CONFIG_OVERLAY_FS_INDEX=y
or
 echo Y > /sys/modules/overlay/params/index

The reason is that mount option uuid=off has the undesired side effect
of disabling index feature.

uuid=null is exactly the same as uuid=off for the purpose of this test
but without the undesired side effect.

The test was created to test the new modes uuid=null/auto/on, so the
fact that is is testing the mode uuid=off is just an oversight.

Covert the use of uuid=off to uuid=null to fix this problem.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---

Zorro,

Following your report that the new test overlay/084 is failing with
non-default overlayfs Kconfig [1], I reran the existing overlay tests
with non-default config.

The run with CONFIG_OVERLAY_FS_INDEX=y found another failure in a test
that was added recently to cover a new feature in v6.6.

Thanks,
Amir.


[1] https://lore.kernel.org/fstests/20231210204503.poggjg4z57eg2nn7@dell-per750-06-vm-08.rhts.eng.pek2.redhat.com/

 tests/overlay/081 | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/tests/overlay/081 b/tests/overlay/081
index 05156a3c..481e9931 100755
--- a/tests/overlay/081
+++ b/tests/overlay/081
@@ -5,7 +5,7 @@
 # FSQA Test No. 081
 #
 # Test persistent (and optionally unique) overlayfs fsid
-# with mount options uuid=null/on introduced in kernel v6.6
+# with mount options uuid=null/auto/on introduced in kernel v6.6
 #
 . ./common/preamble
 _begin_fstest auto quick
@@ -55,7 +55,7 @@ _scratch_mount
 
 ovl_fsid=$(stat -f -c '%i' $test_dir)
 [[ "$ovl_fsid" == "$upper_fsid" ]] || \
-	echo "Overlayfs (uuid=auto) and upper fs fsid differ"
+	echo "Overlayfs (after uuid=null) and upper fs fsid differ"
 
 $UMOUNT_PROG $SCRATCH_MNT
 
@@ -74,16 +74,16 @@ _scratch_mount
 
 ovl_fsid=$(stat -f -c '%i' $test_dir)
 [[ "$ovl_fsid" == "$ovl_unique_fsid" ]] || \
-	echo "Overlayfs (uuid=auto) unique fsid is not persistent"
+	echo "Overlayfs (after uuid=on) unique fsid is not persistent"
 
 $UMOUNT_PROG $SCRATCH_MNT
 
 # Test ignore existing persistent fsid on explicit opt-out
-_scratch_mount -o uuid=off
+_scratch_mount -o uuid=null
 
 ovl_fsid=$(stat -f -c '%i' $test_dir)
 [[ "$ovl_fsid" == "$upper_fsid" ]] || \
-	echo "Overlayfs (uuid=off) and upper fs fsid differ"
+	echo "Overlayfs (uuid=null) and upper fs fsid differ"
 
 $UMOUNT_PROG $SCRATCH_MNT
 
@@ -92,7 +92,7 @@ _overlay_scratch_mount_dirs "$upperdir:$lowerdir" "-" "-" -o ro,uuid=on
 
 ovl_fsid=$(stat -f -c '%i' $test_dir)
 [[ "$ovl_fsid" == "$lower_fsid" ]] || \
-	echo "Overlayfs (uuid=null) and lower fs fsid differ"
+	echo "Overlayfs (no upper) and lower fs fsid differ"
 
 # Re-create fresh overlay layers, so following (uuid=auto) mounts
 # will behave as first time mount of a new overlayfs
@@ -110,7 +110,7 @@ _scratch_mount
 ovl_fsid=$(stat -f -c '%i' $test_dir)
 ovl_unique_fsid=$ovl_fsid
 [[ "$ovl_fsid" != "$upper_fsid" ]] || \
-	echo "Overlayfs (uuid=auto) and upper fs fsid are the same"
+	echo "Overlayfs (new) and upper fs fsid are the same"
 
 $UMOUNT_PROG $SCRATCH_MNT
 
-- 
2.34.1