dataVolumeTemplate

---
apiVersion: cdi.kubevirt.io/v1beta1
kind: DataVolume
metadata:
  name: pvc-cirros-2
spec:
  source:
    pvc:
      namespace: default
      name: pvc-cirros 
  pvc:
    storageClassName: "rook-ceph-block"
    accessModes:
      - ReadWriteOnce
    resources:
      requests:
        storage: 2000Mi

apiVersion: kubevirt.io/v1
kind: VirtualMachine
metadata:
  name: testvm
spec:
  running: false
  template:
    metadata:
      labels:
        kubevirt.io/size: small
        kubevirt.io/domain: testvm
    spec:
      domain:
        devices:
          disks:
            - name: root-disk
              disk:
                bus: virtio
#            - name: datadisk
#              disk:
#                bus: virtio
          interfaces:
          - name: default
            masquerade: {}
        resources:
          requests:
            memory: 64M
      networks:
      - name: default
        pod: {}
      volumes:
#      - name: datadisk
#        persistentVolumeClaim:
#          claimName: pvc-datadisk
      - name: root-disk
        dataVolume:
          name: pvc-cirros-2
  dataVolumeTemplates:
  - metadata:
      name: pvc-cirros-2
    spec:
      pvc:
        accessModes:
        - ReadWriteOnce
        resources:
          requests:
            storage: 2Gi
      source:
        pvc:
          namespace: "default"
          name: "pvc-cirros-2"