tests: lvconvert cache usage of thin pool

Checked stacking usage of thin pool data volume being cached.

test/shell/lvconvert-cache-thin.sh

@@ -0,0 +1,50 @@
+#!/bin/sh
+# Copyright (C) 2014 Red Hat, Inc. All rights reserved.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+# Exercise usage of stacked cache volume used in thin pool volumes
+
+. lib/inittest
+
+aux have_cache 1 3 0 || skip
+aux have_thin 1 0 0 || skip
+
+aux prepare_vg 5 80
+
+lvcreate -L10 -n cpool $vg
+lvcreate -L10 -n tpool $vg
+lvcreate -L10 -n $lv1 $vg
+
+lvconvert --yes --cache --cachepool cpool $vg/tpool
+
+# Currently the only allowed stacking is cache thin data volume
+lvconvert --yes --type thin-pool $vg/tpool
+
+lvcreate -V10 -T -n $lv2 $vg/tpool
+
+aux mkdev_md5sum $vg $lv2
+
+lvconvert --splitcache $vg/tpool
+
+check dev_md5sum $vg $lv2
+lvchange -an $vg
+lvchange -ay $vg
+check dev_md5sum $vg $lv2
+
+lvs -a $vg
+lvconvert --yes --cache --cachepool cpool $vg/tpool
+
+lvconvert --yes -T --thinpool $vg/tpool $vg/$lv1
+check lv_field $vg/tpool segtype "thin-pool"
+check lv_field $vg/$lv1 segtype "thin"
+lvconvert --uncache $vg/tpool
+lvs -a $vg
+
+vgremove -f $vg