Merge pull request kubevirt#6557 from jean-edouard/cherry-pick-6482-t…

…o-release-0.46

[release-0.46] migration: generate empty isos on target for cloud-inits, configmaps, secrets, ...

api/openapi-spec/swagger.json

@@ -13392,6 +13392,11 @@
       "description": "Reason is a brief description of why we are in the current hotplug volume phase",
       "type": "string"
      },
+     "size": {
+      "description": "Represents the size of the volume",
+      "type": "integer",
+      "format": "int64"
+     },
      "target": {
       "description": "Target is the target name used when adding the volume to the VM, eg: vda",
       "type": "string"

pkg/cloud-init/cloud-init.go

@@ -25,6 +25,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -67,6 +68,7 @@ type CloudInitData struct {
 	UserData            string
 	NetworkData         string
 	DevicesData         *[]DeviceData
+	VolumeName          string
 }
 
 type PublicSSHKey struct {
@@ -117,6 +119,7 @@ func ReadCloudInitVolumeDataSource(vmi *v1.VirtualMachineInstance, secretSourceD
 
 			cloudInitData, err = readCloudInitNoCloudSource(volume.CloudInitNoCloud)
 			cloudInitData.NoCloudMetaData = readCloudInitNoCloudMetaData(vmi.Name, hostname, vmi.Namespace)
+			cloudInitData.VolumeName = volume.Name
 			return cloudInitData, err
 		}
 		if volume.CloudInitConfigDrive != nil {
@@ -128,6 +131,7 @@ func ReadCloudInitVolumeDataSource(vmi *v1.VirtualMachineInstance, secretSourceD
 
 			cloudInitData, err = readCloudInitConfigDriveSource(volume.CloudInitConfigDrive)
 			cloudInitData.ConfigDriveMetaData = readCloudInitConfigDriveMetaData(string(vmi.UID), vmi.Name, hostname, vmi.Namespace, keys)
+			cloudInitData.VolumeName = volume.Name
 			return cloudInitData, err
 		}
 	}
@@ -465,6 +469,59 @@ func removeLocalData(domain string, namespace string) error {
 	return err
 }
 
+func GenerateEmptyIso(vmiName string, namespace string, data *CloudInitData, size int64) error {
+	precond.MustNotBeEmpty(vmiName)
+	precond.MustNotBeNil(data)
+
+	var err error
+	var isoStaging, iso string
+
+	switch data.DataSource {
+	case DataSourceNoCloud, DataSourceConfigDrive:
+		iso = GetIsoFilePath(data.DataSource, vmiName, namespace)
+	default:
+		return fmt.Errorf("invalid cloud-init data source: '%v'", data.DataSource)
+	}
+	isoStaging = fmt.Sprintf("%s.staging", iso)
+
+	err = diskutils.RemoveFilesIfExist(isoStaging)
+	if err != nil {
+		return err
+	}
+
+	err = util.MkdirAllWithNosec(path.Dir(isoStaging))
+	if err != nil {
+		log.Log.V(2).Reason(err).Errorf("unable to create cloud-init base path %s", path.Dir(isoStaging))
+		return err
+	}
+
+	f, err := os.Create(isoStaging)
+	if err != nil {
+		return fmt.Errorf("failed to create empty iso: '%s'", isoStaging)
+	}
+
+	err = util.WriteBytes(f, 0, size)
+	if err != nil {
+		return err
+	}
+	util.CloseIOAndCheckErr(f, &err)
+	if err != nil {
+		return err
+	}
+
+	if err := diskutils.DefaultOwnershipManager.SetFileOwnership(isoStaging); err != nil {
+		return err
+	}
+	err = os.Rename(isoStaging, iso)
+	if err != nil {
+		log.Log.Reason(err).Errorf("Cloud-init failed to rename file %s to %s", isoStaging, iso)
+		return err
+	}
+
+	log.Log.V(2).Infof("generated empty iso file %s", iso)
+	return nil
+}
+
 func GenerateLocalData(vmiName string, namespace string, data *CloudInitData) error {
 	precond.MustNotBeEmpty(vmiName)
 	precond.MustNotBeNil(data)

pkg/cloud-init/cloud-init_test.go

@@ -502,6 +502,7 @@ var _ = Describe("CloudInit", func() {
 			})
 		})
 	})
+
 	Describe("GenerateLocalData", func() {
 		It("should cleanly run twice", func() {
 			namespace := "fake-namespace"
@@ -517,7 +518,6 @@ var _ = Describe("CloudInit", func() {
 			err = GenerateLocalData(domain, namespace, cloudInitData)
 			Expect(err).NotTo(HaveOccurred())
 		})
-
 	})
 
 	Describe("PrepareLocalPath", func() {

pkg/config/BUILD.bazel

@@ -14,6 +14,7 @@ go_library(
     visibility = ["//visibility:public"],
     deps = [
         "//pkg/ephemeral-disk-utils:go_default_library",
+        "//pkg/util:go_default_library",
         "//staging/src/kubevirt.io/client-go/api/v1:go_default_library",
     ],
 )

pkg/config/config-map.go

@@ -37,7 +37,7 @@ func GetConfigMapDiskPath(volumeName string) string {
 }
 
 // CreateConfigMapDisks creates ConfigMap iso disks which are attached to vmis
-func CreateConfigMapDisks(vmi *v1.VirtualMachineInstance) error {
+func CreateConfigMapDisks(vmi *v1.VirtualMachineInstance, emptyIso bool) error {
 	for _, volume := range vmi.Spec.Volumes {
 		if volume.ConfigMap != nil {
 			var filesPath []string
@@ -47,7 +47,11 @@ func CreateConfigMapDisks(vmi *v1.VirtualMachineInstance) error {
 			}
 
 			disk := GetConfigMapDiskPath(volume.Name)
-			if err := createIsoConfigImage(disk, volume.ConfigMap.VolumeLabel, filesPath); err != nil {
+			vmiIsoSize, err := findIsoSize(vmi, &volume, emptyIso)
+			if err != nil {
+				return err
+			}
+			if err := createIsoConfigImage(disk, volume.ConfigMap.VolumeLabel, filesPath, vmiIsoSize); err != nil {
 				return err
 			}
 

pkg/config/config-map_test.go

@@ -64,7 +64,7 @@ var _ = Describe("ConfigMap", func() {
 			},
 		})
 
-		err := CreateConfigMapDisks(vmi)
+		err := CreateConfigMapDisks(vmi, false)
 		Expect(err).NotTo(HaveOccurred())
 		_, err = os.Stat(filepath.Join(ConfigMapDisksDir, "configmap-volume.iso"))
 		Expect(err).NotTo(HaveOccurred())

pkg/config/config.go

@@ -20,16 +20,22 @@
 package config
 
 import (
+	"fmt"
 	"os"
 	"os/exec"
 	"path/filepath"
+
+	"kubevirt.io/kubevirt/pkg/util"
+
+	v1 "kubevirt.io/client-go/api/v1"
 )
 
 type (
 	// Type represents allowed config types like ConfigMap or Secret
 	Type string
 
-	isoCreationFunc func(output string, volID string, files []string) error
+	isoCreationFunc      func(output string, volID string, files []string) error
+	emptyIsoCreationFunc func(output string, size int64) error
 )
 
 const (
@@ -78,14 +84,20 @@ var (
 	// ServiceAccountDiskName represents the name of the ServiceAccount iso image
 	ServiceAccountDiskName = "service-account.iso"
 
-	createISOImage = defaultCreateIsoImage
+	createISOImage      = defaultCreateIsoImage
+	createEmptyISOImage = defaultCreateEmptyIsoImage
 )
 
 // The unit test suite uses this function
 func setIsoCreationFunction(isoFunc isoCreationFunc) {
 	createISOImage = isoFunc
 }
 
+// The unit test suite uses this function
+func setEmptyIsoCreationFunction(emptyIsoFunc emptyIsoCreationFunc) {
+	createEmptyISOImage = emptyIsoFunc
+}
+
 func getFilesLayout(dirPath string) ([]string, error) {
 	var filesPath []string
 	files, err := os.ReadDir(dirPath)
@@ -129,10 +141,40 @@ func defaultCreateIsoImage(output string, volID string, files []string) error {
 	return nil
 }
 
-func createIsoConfigImage(output string, volID string, files []string) error {
-	err := createISOImage(output, volID, files)
+func defaultCreateEmptyIsoImage(output string, size int64) error {
+	f, err := os.Create(output)
+	if err != nil {
+		return fmt.Errorf("failed to create empty iso: '%s'", output)
+	}
+	err = util.WriteBytes(f, 0, size)
+	if err != nil {
+		return err
+	}
+	util.CloseIOAndCheckErr(f, &err)
+	return err
+}
+
+func createIsoConfigImage(output string, volID string, files []string, size int64) error {
+	var err error
+	if size == 0 {
+		err = createISOImage(output, volID, files)
+	} else {
+		err = createEmptyISOImage(output, size)
+	}
 	if err != nil {
 		return err
 	}
 	return nil
 }
+
+func findIsoSize(vmi *v1.VirtualMachineInstance, volume *v1.Volume, emptyIso bool) (int64, error) {
+	if emptyIso {
+		for _, vs := range vmi.Status.VolumeStatus {
+			if vs.Name == volume.Name {
+				return vs.Size, nil
+			}
+		}
+		return 0, fmt.Errorf("failed to find the status of volume %s", volume.Name)
+	}
+	return 0, nil
+}

pkg/config/config_test.go

@@ -73,7 +73,7 @@ var _ = Describe("Creating config images", func() {
 
 		It("Should create an iso image", func() {
 			imgPath := filepath.Join(tempISODir, "volume1.iso")
-			err := createIsoConfigImage(imgPath, "", expectedLayout)
+			err := createIsoConfigImage(imgPath, "", expectedLayout, 0)
 			Expect(err).NotTo(HaveOccurred())
 			_, err = os.Stat(imgPath)
 			Expect(err).NotTo(HaveOccurred())

pkg/config/downwardapi.go

@@ -37,7 +37,7 @@ func GetDownwardAPIDiskPath(volumeName string) string {
 }
 
 // CreateDownwardAPIDisks creates DownwardAPI iso disks which are attached to vmis
-func CreateDownwardAPIDisks(vmi *v1.VirtualMachineInstance) error {
+func CreateDownwardAPIDisks(vmi *v1.VirtualMachineInstance, emptyIso bool) error {
 	for _, volume := range vmi.Spec.Volumes {
 		if volume.DownwardAPI != nil {
 
@@ -48,7 +48,11 @@ func CreateDownwardAPIDisks(vmi *v1.VirtualMachineInstance) error {
 			}
 
 			disk := GetDownwardAPIDiskPath(volume.Name)
-			if err := createIsoConfigImage(disk, volume.DownwardAPI.VolumeLabel, filesPath); err != nil {
+			vmiIsoSize, err := findIsoSize(vmi, &volume, emptyIso)
+			if err != nil {
+				return err
+			}
+			if err := createIsoConfigImage(disk, volume.DownwardAPI.VolumeLabel, filesPath, vmiIsoSize); err != nil {
 				return err
 			}
 

pkg/config/downwardapi_test.go

@@ -70,7 +70,7 @@ var _ = Describe("DownwardAPI", func() {
 			},
 		})
 
-		err := CreateDownwardAPIDisks(vmi)
+		err := CreateDownwardAPIDisks(vmi, false)
 		Expect(err).NotTo(HaveOccurred())
 		_, err = os.Stat(filepath.Join(DownwardAPIDisksDir, "downwardapi-volume.iso"))
 		Expect(err).NotTo(HaveOccurred())

pkg/config/secret.go

@@ -37,7 +37,7 @@ func GetSecretDiskPath(volumeName string) string {
 }
 
 // CreateSecretDisks creates Secret iso disks which are attached to vmis
-func CreateSecretDisks(vmi *v1.VirtualMachineInstance) error {
+func CreateSecretDisks(vmi *v1.VirtualMachineInstance, emptyIso bool) error {
 	for _, volume := range vmi.Spec.Volumes {
 		if volume.Secret != nil {
 
@@ -48,7 +48,11 @@ func CreateSecretDisks(vmi *v1.VirtualMachineInstance) error {
 			}
 
 			disk := GetSecretDiskPath(volume.Name)
-			if err := createIsoConfigImage(disk, volume.Secret.VolumeLabel, filesPath); err != nil {
+			vmiIsoSize, err := findIsoSize(vmi, &volume, emptyIso)
+			if err != nil {
+				return err
+			}
+			if err := createIsoConfigImage(disk, volume.Secret.VolumeLabel, filesPath, vmiIsoSize); err != nil {
 				return err
 			}
 

pkg/config/secret_test.go

@@ -61,7 +61,7 @@ var _ = Describe("Secret", func() {
 			},
 		})
 
-		err := CreateSecretDisks(vmi)
+		err := CreateSecretDisks(vmi, false)
 		Expect(err).NotTo(HaveOccurred())
 		_, err = os.Stat(filepath.Join(SecretDisksDir, "secret-volume.iso"))
 		Expect(err).NotTo(HaveOccurred())

pkg/config/service-account.go

@@ -32,7 +32,7 @@ func GetServiceAccountDiskPath() string {
 }
 
 // CreateServiceAccountDisk creates the ServiceAccount iso disk which is attached to vmis
-func CreateServiceAccountDisk(vmi *v1.VirtualMachineInstance) error {
+func CreateServiceAccountDisk(vmi *v1.VirtualMachineInstance, emptyIso bool) error {
 	for _, volume := range vmi.Spec.Volumes {
 		if volume.ServiceAccount != nil {
 			var filesPath []string
@@ -42,7 +42,11 @@ func CreateServiceAccountDisk(vmi *v1.VirtualMachineInstance) error {
 			}
 
 			disk := GetServiceAccountDiskPath()
-			if err := createIsoConfigImage(disk, "", filesPath); err != nil {
+			vmiIsoSize, err := findIsoSize(vmi, &volume, emptyIso)
+			if err != nil {
+				return err
+			}
+			if err := createIsoConfigImage(disk, "", filesPath, vmiIsoSize); err != nil {
 				return err
 			}
 

pkg/config/service-account_test.go

@@ -61,7 +61,7 @@ var _ = Describe("ServiceAccount", func() {
 			},
 		})
 
-		err := CreateServiceAccountDisk(vmi)
+		err := CreateServiceAccountDisk(vmi, false)
 		Expect(err).NotTo(HaveOccurred())
 		_, err = os.Stat(filepath.Join(ServiceAccountDiskDir, ServiceAccountDiskName))
 		Expect(err).NotTo(HaveOccurred())

pkg/config/sysprep.go

@@ -64,12 +64,16 @@ func validateAutounattendPresence(dirPath string) error {
 }
 
 // CreateSysprepDisks creates Sysprep iso disks which are attached to vmis from either ConfigMap or Secret as a source
-func CreateSysprepDisks(vmi *v1.VirtualMachineInstance) error {
+func CreateSysprepDisks(vmi *v1.VirtualMachineInstance, emptyIso bool) error {
 	for _, volume := range vmi.Spec.Volumes {
 		if !shouldCreateSysprepDisk(volume.Sysprep) {
 			continue
 		}
-		if err := createSysprepDisk(volume.Name); err != nil {
+		vmiIsoSize, err := findIsoSize(vmi, &volume, emptyIso)
+		if err != nil {
+			return err
+		}
+		if err := createSysprepDisk(volume.Name, vmiIsoSize); err != nil {
 			return err
 		}
 	}
@@ -80,7 +84,7 @@ func shouldCreateSysprepDisk(volumeSysprep *v1.SysprepSource) bool {
 	return volumeSysprep != nil && sysprepVolumeHasContents(volumeSysprep)
 }
 
-func createSysprepDisk(volumeName string) error {
+func createSysprepDisk(volumeName string, size int64) error {
 	sysprepSourcePath := GetSysprepSourcePath(volumeName)
 	if err := validateAutounattendPresence(sysprepSourcePath); err != nil {
 		return err
@@ -90,12 +94,12 @@ func createSysprepDisk(volumeName string) error {
 		return err
 	}
 
-	return createIsoImageAndSetFileOwnership(volumeName, filesPath)
+	return createIsoImageAndSetFileOwnership(volumeName, filesPath, size)
 }
 
-func createIsoImageAndSetFileOwnership(volumeName string, filesPath []string) error {
+func createIsoImageAndSetFileOwnership(volumeName string, filesPath []string, size int64) error {
 	disk := GetSysprepDiskPath(volumeName)
-	if err := createIsoConfigImage(disk, sysprepVolumeLabel, filesPath); err != nil {
+	if err := createIsoConfigImage(disk, sysprepVolumeLabel, filesPath, size); err != nil {
 		return err
 	}
 	if err := ephemeraldiskutils.DefaultOwnershipManager.SetFileOwnership(disk); err != nil {