ZTS: issue openzfs#14223: add check for /dev changes after snapshot r…

…ename

After renaming a snapshot with 'snapdev=visible' ensure that the /dev
entries are updated to reflect the rename.

Signed-off-by: James Dingwall <james@dingwall.me.uk>

tests/zfs-tests/tests/functional/zvol/zvol_misc/zvol_misc_snapdev.ksh

@@ -118,4 +118,15 @@ verify_inherited 'snapdev' 'hidden' $SUBZVOL $VOLFS
 blockdev_missing $SUBSNAPDEV
 blockdev_exists $SNAPDEV
 
+# 4. Verify "rename" is correctly reflected when "snapdev=visible"
+# 4.1 First create a snapshot and verify the device is present
+log_must zfs snapshot $SNAP
+log_must zfs set snapdev=visible $ZVOL
+blockdev_exists $SNAPDEV
+# 4.2 rename the snapshot and verify the devices are updated
+log_must zfs rename $SNAP $SNAP-new
+blockdev_missing $SNAPDEV
+blockdev_exists $SNAPDEV-new
+log_must zfs destroy $SNAP-new
+
 log_pass "ZFS volume property 'snapdev' works as expected"