}
	if spec.Volume != nil {
		return spec.Name(), nil
	} else if spec.PersistentVolume != nil {
		if spec.PersistentVolume.Spec.PersistentVolumeSource.GCEPersistentDisk != nil {
			return spec.PersistentVolume.Spec.PersistentVolumeSource.GCEPersistentDisk.PDName, nil
		} else if spec.PersistentVolume.Spec.PersistentVolumeSource.NFS != nil {
			return spec.PersistentVolume.Spec.PersistentVolumeSource.NFS.Server, nil

    scope:       "*"
  clientConfig:
    url: "https://127.0.0.1:9001/admit"
    caBundle: "__CLOUD_PVL_ADMISSION_CA_CERT__"
  matchConditions:
  - name: "only-gce"
    expression: "has(object.spec.gcePersistentDisk)"
  admissionReviewVersions: ["v1"]
  sideEffects: None
  timeoutSeconds: 5

                        "hostPath": null,
                        "emptyDir": {
                            "medium": ""
                        },
                        "gcePersistentDisk": null,
                        "awsElasticBlockStore": null,
                        "gitRepo": null,
                        "secret": null,
                        "nfs": null,
                        "iscsi": null,

		ObjectMeta: metav1.ObjectMeta{
			Name: "pod1",
			UID:  "pod1uid",
		},
		Spec: v1.PodSpec{
			Volumes: []v1.Volume{
				{
					Name: "volume-name",
					VolumeSource: v1.VolumeSource{
						GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{
							PDName: "fake-device1",
						},
					},
				},
			},
		},
	}
	volumeSpec := &volume.Spec{Volume: &pod.Spec.Volumes[0]}
	devicePath := "fake/device/path"

// with apply.
type PersistentVolumeSourceApplyConfiguration struct {
	GCEPersistentDisk    *GCEPersistentDiskVolumeSourceApplyConfiguration    `json:"gcePersistentDisk,omitempty"`
	AWSElasticBlockStore *AWSElasticBlockStoreVolumeSourceApplyConfiguration `json:"awsElasticBlockStore,omitempty"`

		},
		Spec: v1.PersistentVolumeSpec{
			Capacity: v1.ResourceList{
				v1.ResourceName(v1.ResourceStorage): resource.MustParse("1G"),
			},
			PersistentVolumeSource: v1.PersistentVolumeSource{
				GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{},
			},
			AccessModes: []v1.PersistentVolumeAccessMode{v1.ReadWriteOnce, v1.ReadOnlyMany},
			// this one we're pretending is already bound

	for _, existingVolume := range pod.Spec.Volumes {
		// Same GCE disk mounted by multiple pods conflicts unless all pods mount it read-only.
		if volume.GCEPersistentDisk != nil && existingVolume.GCEPersistentDisk != nil {
			disk, existingDisk := volume.GCEPersistentDisk, existingVolume.GCEPersistentDisk
			if disk.PDName == existingDisk.PDName && !(disk.ReadOnly && existingDisk.ReadOnly) {
				return true
			}
		}

}

func checkMountOption(pv *api.PersistentVolume) field.ErrorList {
	allErrs := field.ErrorList{}
	// if PV is of these types we don't return errors
	// since mount options is supported
	if pv.Spec.GCEPersistentDisk != nil ||
		pv.Spec.AWSElasticBlockStore != nil ||
		pv.Spec.Glusterfs != nil ||
		pv.Spec.NFS != nil ||
		pv.Spec.RBD != nil ||
		pv.Spec.Quobyte != nil ||
		pv.Spec.ISCSI != nil ||
		pv.Spec.Cinder != nil ||

		ObjectMeta: metav1.ObjectMeta{
			Name: "pod3",
			UID:  "pod3uid",
		},
		Spec: v1.PodSpec{
			Volumes: []v1.Volume{
				{
					Name: "volume-name",
					VolumeSource: v1.VolumeSource{
						GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{
							PDName: "fake-device1",
						},
					},
				},
			},
		},
	}

	volumeSpec := &volume.Spec{Volume: &pod.Spec.Volumes[0]}

			Volumes: []v1.Volume{
				{
					Name: "volume-name",
					VolumeSource: v1.VolumeSource{
						GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{
							PDName: "fake-device1",
						},
					},
				},
				{
					Name: "volume-name2",
					VolumeSource: v1.VolumeSource{
						GCEPersistentDisk: &v1.GCEPersistentDiskVolumeSource{
							PDName: "fake-device2",
						},
					},
				},