Merge pull request kubevirt#1733 from vladikr/migrate_with_shared_pvc

Migrate with shared PVC

api/openapi-spec/swagger.json

@@ -4556,6 +4556,10 @@
       "description": "The path to HostDisk image located on the cluster",
       "type": "string"
      },
+     "shared": {
+      "description": "Shared indicate whether the path is shared between nodes",
+      "type": "boolean"
+     },
      "type": {
       "description": "Contains information if disk.img exists or should be created\nallowed options are 'Disk' and 'DiskOrCreate'",
       "type": "string"
@@ -5969,6 +5973,10 @@
        "$ref": "#/definitions/v1.VirtualMachineInstanceNetworkInterface"
       }
      },
+     "migrationMethod": {
+      "description": "Represents the method using which the vmi can be migrated: live migration or block migration",
+      "type": "string"
+     },
      "migrationState": {
       "description": "Represents the status of a live migration",
       "$ref": "#/definitions/v1.VirtualMachineInstanceMigrationState"

cmd/container-disk-v1alpha/entry-point.sh

@@ -46,7 +46,7 @@ if [ $? -ne 0 ]; then
 		echo "Failed to convert image $IMAGE_PATH to .raw file"
 		exit 1
 	fi
-else 
+else
 	cp $IMAGE_PATH ${COPY_PATH}.${IMAGE_EXTENSION}
 	if [ $? -ne 0 ]; then
 		echo "Failed to copy $IMAGE_PATH to $COPY_PATH.${IMAGE_EXTENSION}"

images/cdi-http-import-server/Dockerfile

@@ -21,7 +21,7 @@ FROM fedora:28
 LABEL maintainer="The KubeVirt Project <[email protected]>"
 ENV container docker
 
-RUN dnf install -y nginx qemu-guest-agent \
+RUN dnf install -y nginx qemu-guest-agent qemu-img scsi-target-utils \
     && dnf -y clean all
 
 RUN mkdir -p /usr/share/nginx/html/images \
@@ -33,3 +33,8 @@ RUN cp /usr/bin/qemu-ga /usr/share/nginx/html/
 ADD nginx.conf /etc/nginx/
 
 EXPOSE 80
+
+ADD entry-point.sh /
+ADD expose-as-iscsi.sh /
+
+CMD ["/entry-point.sh"]

images/cdi-http-import-server/entry-point.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+#
+# This file is part of the KubeVirt project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Copyright 2017 Red Hat, Inc.
+#
+
+# https://fedoraproject.org/wiki/Scsi-target-utils_Quickstart_Guide
+
+trap 'echo "Graceful exit"; exit 0' SIGINT SIGQUIT SIGTERM
+
+ALPINE_IMAGE_PATH=/usr/share/nginx/html/images/alpine.iso
+IMAGE_PATH=/images
+
+if [ -n "$AS_ISCSI" ]; then
+    mkdir -p $IMAGE_PATH
+    /usr/bin/qemu-img convert $ALPINE_IMAGE_PATH $IMAGE_PATH/alpine.raw
+    if [ $? -ne 0 ]; then
+        echo "Failed to convert image $ALPINE_IMAGE_PATH to .raw file"
+        exit 1
+    fi
+
+    touch /tmp/healthy
+    bash expose-as-iscsi.sh "${IMAGE_PATH}/alpine.raw"
+fi

images/cdi-http-import-server/expose-as-iscsi.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/bash
+
+IMAGE_PATH="$1"
+
+if [ ! -f "$IMAGE_PATH" ]; then
+    echo "vm image '$IMAGE_PATH' not found"
+    exit 1
+fi
+
+# USING 'set -e' error detection for everything below this point.
+set -e
+
+PORT=${PORT:-3260}
+WWN=${WWN:-iqn.2018-01.io.kubevirt:wrapper}
+LUNID=1
+
+echo "Starting tgtd at port $PORT"
+tgtd -f --iscsi portal="0.0.0.0:${PORT}" &
+sleep 5
+
+echo "Adding target and exposing it"
+tgtadm --lld iscsi --mode target --op new --tid=1 --targetname $WWN
+tgtadm --lld iscsi --mode target --op bind --tid=1 -I ALL
+
+if [ -n "$PASSWORD" ]; then
+    echo "Adding authentication for user $USERNAME"
+    tgtadm --lld iscsi --op new --mode account --user $USERNAME --password $PASSWORD
+    tgtadm --lld iscsi --op bind --mode account --tid=1 --user $USERNAME
+fi
+
+echo "Adding volume file as LUN"
+tgtadm --lld iscsi --mode logicalunit --op new --tid=1 --lun=$LUNID -b $IMAGE_PATH
+tgtadm --lld iscsi --mode logicalunit --op update --tid=1 --lun=$LUNID --params thin_provisioning=1
+
+echo "Start monitoring"
+touch previous_state
+while true; do
+    tgtadm --lld iscsi --mode target --op show >current_state
+    diff -q previous_state current_state || (
+        date
+        cat current_state
+    )
+    mv -f current_state previous_state
+    sleep 5
+done

pkg/api/v1/schema.go

@@ -53,6 +53,8 @@ type HostDisk struct {
 	// Capacity of the sparse disk
 	// +optional
 	Capacity resource.Quantity `json:"capacity,omitempty"`
+	// Shared indicate whether the path is shared between nodes
+	Shared *bool `json:"shared,omitempty"`
 }
 
 // ConfigMapVolumeSource adapts a ConfigMap into a volume.

pkg/api/v1/types.go

@@ -197,6 +197,8 @@ type VirtualMachineInstanceStatus struct {
 	Interfaces []VirtualMachineInstanceNetworkInterface `json:"interfaces,omitempty"`
 	// Represents the status of a live migration
 	MigrationState *VirtualMachineInstanceMigrationState `json:"migrationState,omitempty"`
+	// Represents the method using which the vmi can be migrated: live migration or block migration
+	MigrationMethod VirtualMachineInstanceMigrationMethod `json:"migrationMethod,omitempty"`
 }
 
 // Required to satisfy Object interface
@@ -269,6 +271,11 @@ const (
 
 	// Reflects whether the QEMU guest agent is connected through the channel
 	VirtualMachineInstanceAgentConnected VirtualMachineInstanceConditionType = "AgentConnected"
+
+	// Indicates whether the VMI is live migratable
+	VirtualMachineInstanceIsMigratable VirtualMachineInstanceConditionType = "LiveMigratable"
+	// Reason means that VMI is not live migratioable because of it's disks collection
+	VirtualMachineInstanceReasonDisksNotMigratable = "DisksNotLiveMigratable"
 )
 
 // ---
@@ -334,6 +341,17 @@ type VirtualMachineInstanceMigrationState struct {
 	MigrationUID types.UID `json:"migrationUid,omitempty"`
 }
 
+// ---
+// +k8s:openapi-gen=true
+type VirtualMachineInstanceMigrationMethod string
+
+const (
+	// BlockMigration means that all VirtualMachineInstance disks should be copied over to the destination host
+	BlockMigration VirtualMachineInstanceMigrationMethod = "BlockMigration"
+	// LiveMigration means that VirtualMachineInstance disks will not be copied over to the destination host
+	LiveMigration VirtualMachineInstanceMigrationMethod = "LiveMigration"
+)
+
 // VirtualMachineInstancePhase is a label for the condition of a VirtualMachineInstance at the current time.
 // ---
 // +k8s:openapi-gen=true

pkg/host-disk/host-disk.go

@@ -54,11 +54,13 @@ func ReplacePVCByHostDisk(vmi *v1.VirtualMachineInstance, clientset kubecli.Kube
 			} else if isBlockVolumePVC {
 				continue
 			}
+			isSharedPvc := types.IsPVCShared(pvc)
 
 			volumeSource.HostDisk = &v1.HostDisk{
 				Path:     getPVCDiskImgPath(vmi.Spec.Volumes[i].Name),
 				Type:     v1.HostDiskExistsOrCreate,
 				Capacity: pvc.Status.Capacity[k8sv1.ResourceStorage],
+				Shared:   &isSharedPvc,
 			}
 			// PersistenVolumeClaim is replaced by HostDisk
 			volumeSource.PersistentVolumeClaim = nil

pkg/util/types/pvc.go

@@ -58,3 +58,23 @@ func isPVCBlock(pvc *k8sv1.PersistentVolumeClaim) bool {
 	// VolumeMode is Block, that unambiguously answers the question
 	return pvc.Spec.VolumeMode != nil && *pvc.Spec.VolumeMode == k8sv1.PersistentVolumeBlock
 }
+
+func IsPVCShared(pvc *k8sv1.PersistentVolumeClaim) (isShared bool) {
+	for _, accessMode := range pvc.Spec.AccessModes {
+		if accessMode == k8sv1.ReadWriteMany {
+			isShared = true
+			break
+		}
+	}
+	return
+}
+
+func IsSharedPVCFromClient(client kubecli.KubevirtClient, namespace string, claimName string) (pvc *k8sv1.PersistentVolumeClaim, isShared bool, err error) {
+	pvc, err = client.CoreV1().PersistentVolumeClaims(namespace).Get(claimName, v1.GetOptions{})
+	if err != nil {
+		return nil, false, err
+	}
+
+	isShared = IsPVCShared(pvc)
+	return pvc, isShared, nil
+}

pkg/util/types/pvc_test.go

@@ -57,7 +57,8 @@ var _ = Describe("PVC utils test", func() {
 		TypeMeta:   metav1.TypeMeta{Kind: "PersistentVolumeClaim", APIVersion: "v1"},
 		ObjectMeta: metav1.ObjectMeta{Namespace: namespace, Name: blockName},
 		Spec: kubev1.PersistentVolumeClaimSpec{
-			VolumeMode: &modeBlock,
+			VolumeMode:  &modeBlock,
+			AccessModes: []kubev1.PersistentVolumeAccessMode{kubev1.ReadWriteMany},
 		},
 	}
 
@@ -144,6 +145,13 @@ var _ = Describe("PVC utils test", func() {
 			Expect(exists).To(BeTrue(), "PVC was found")
 			Expect(isBlock).To(Equal(true), "Is blockdevice PVC")
 		})
+		It("should detect shared block device for block VolumeMode", func() {
+			pvc, isShared, err := IsSharedPVCFromClient(virtClient, namespace, blockName)
+			Expect(err).ToNot(HaveOccurred(), "no error occured")
+			Expect(pvc).ToNot(BeNil(), "PVC isn't nil")
+			Expect(pvc.Name).To(Equal(blockName), "correct PVC was found")
+			Expect(isShared).To(Equal(true), "Is PVC Shared")
+		})
 	})
 
 })

pkg/virt-api/webhooks/validating-webhook/validating-webhook.go

@@ -1545,6 +1545,14 @@ func admitMigrationCreate(ar *v1beta1.AdmissionReview) *v1beta1.AdmissionRespons
 		return webhooks.ToAdmissionResponseError(fmt.Errorf("Cannot migrated VMI in finalized state."))
 	}
 
+	// Reject migration jobs for non-migratable VMIs
+	cond := getVMIMigrationCondition(vmi)
+	if cond != nil && cond.Status == k8sv1.ConditionFalse {
+		errMsg := fmt.Errorf("Cannot migrate VMI, Reason: %s, Message: %s",
+			cond.Reason, cond.Message)
+		return webhooks.ToAdmissionResponseError(errMsg)
+	}
+
 	// Don't allow new migration jobs to be introduced when previous migration jobs
 	// are already in flight.
 	if vmi.Status.MigrationState != nil &&
@@ -1560,6 +1568,15 @@ func admitMigrationCreate(ar *v1beta1.AdmissionReview) *v1beta1.AdmissionRespons
 	return &reviewResponse
 }
 
+func getVMIMigrationCondition(vmi *v1.VirtualMachineInstance) (cond *v1.VirtualMachineInstanceCondition) {
+	for _, c := range vmi.Status.Conditions {
+		if c.Type == v1.VirtualMachineInstanceIsMigratable {
+			cond = &c
+		}
+	}
+	return cond
+}
+
 func ServeMigrationCreate(resp http.ResponseWriter, req *http.Request) {
 	serve(resp, req, admitMigrationCreate)
 }

pkg/virt-api/webhooks/validating-webhook/validating-webhook_test.go

@@ -870,6 +870,46 @@ var _ = Describe("Validating Webhook", func() {
 			Expect(resp.Allowed).To(Equal(false))
 		})
 
+		It("should reject Migration spec for non-migratable VMIs", func() {
+			vmi := v1.NewMinimalVMI("testmigratevmi3")
+			vmi.Status.Phase = v1.Succeeded
+			vmi.Status.Conditions = []v1.VirtualMachineInstanceCondition{
+				{
+					Type:    v1.VirtualMachineInstanceIsMigratable,
+					Status:  k8sv1.ConditionFalse,
+					Reason:  v1.VirtualMachineInstanceReasonDisksNotMigratable,
+					Message: "cannot migrate VMI with mixes shared and non-shared volumes",
+				},
+			}
+
+			informers := webhooks.GetInformers()
+			informers.VMIInformer.GetIndexer().Add(vmi)
+
+			migration := v1.VirtualMachineInstanceMigration{
+				ObjectMeta: metav1.ObjectMeta{
+					Namespace: "default",
+				},
+				Spec: v1.VirtualMachineInstanceMigrationSpec{
+					VMIName: "testmigratevmi3",
+				},
+			}
+			migrationBytes, _ := json.Marshal(&migration)
+
+			os.Setenv("FEATURE_GATES", "LiveMigration")
+
+			ar := &v1beta1.AdmissionReview{
+				Request: &v1beta1.AdmissionRequest{
+					Resource: webhooks.MigrationGroupVersionResource,
+					Object: runtime.RawExtension{
+						Raw: migrationBytes,
+					},
+				},
+			}
+
+			resp := admitMigrationCreate(ar)
+			Expect(resp.Allowed).To(Equal(false))
+		})
+
 		It("should reject Migration on update if spec changes", func() {
 			vmi := v1.NewMinimalVMI("testmigratevmiupdate")