Formats supporting backing chain such as qed, vmdk, don't have any other
parameters than the backing store and 'qcow' has only encryption params
which will be tested extra. Add this test case so they are covered since
any further test cases will mainly care about 'qcow2' and 'raw'.
The top level disk image would generate the following '-drive' cmdline:
-drive file=/var/lib/libvirt/images/a,format=qed,if=none,id=drive-dummy
-device virtio-blk-pci,scsi=off,drive=drive-dummy,id=dummy
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
