hypervisor: add initrd image support

If an initrd image is configured in HypervisorConfig or passed in by
annotations, append it to qemu command line arguments.

Fixes: #97

Signed-off-by: Peng Tao <bergwolf@gmail.com>

virtcontainers/asset.go

@@ -34,6 +34,8 @@ func (t assetType) annotations() (string, string, error) {
 		return annotations.KernelPath, annotations.KernelHash, nil
 	case imageAsset:
 		return annotations.ImagePath, annotations.ImageHash, nil
+	case initrdAsset:
+		return annotations.InitrdPath, annotations.InitrdHash, nil
 	case hypervisorAsset:
 		return annotations.HypervisorPath, annotations.HypervisorHash, nil
 	case firmwareAsset:
@@ -46,6 +48,7 @@ func (t assetType) annotations() (string, string, error) {
 const (
 	kernelAsset     assetType = "kernel"
 	imageAsset      assetType = "image"
+	initrdAsset     assetType = "initrd"
 	hypervisorAsset assetType = "hypervisor"
 	firmwareAsset   assetType = "firmware"
 )
@@ -66,6 +69,8 @@ func (a *asset) valid() bool {
 		return true
 	case imageAsset:
 		return true
+	case initrdAsset:
+		return true
 	case hypervisorAsset:
 		return true
 	case firmwareAsset:

virtcontainers/hypervisor.go

@@ -157,6 +157,10 @@ type HypervisorConfig struct {
 	// ImagePath is the guest image host path.
 	ImagePath string
 
+	// InitrdPath is the guest initrd image host path.
+	// ImagePath and InitrdPath cannot be set at the same time.
+	InitrdPath string
+
 	// FirmwarePath is the bios host path
 	FirmwarePath string
 
@@ -225,8 +229,8 @@ func (conf *HypervisorConfig) valid() (bool, error) {
 		return false, fmt.Errorf("Missing kernel path")
 	}
 
-	if conf.ImagePath == "" {
-		return false, fmt.Errorf("Missing image path")
+	if conf.ImagePath == "" && conf.InitrdPath == "" {
+		return false, fmt.Errorf("Missing image and initrd path")
 	}
 
 	if conf.DefaultVCPUs == 0 {
@@ -299,6 +303,8 @@ func (conf *HypervisorConfig) assetPath(t assetType) (string, error) {
 		return conf.KernelPath, nil
 	case imageAsset:
 		return conf.ImagePath, nil
+	case initrdAsset:
+		return conf.InitrdPath, nil
 	case hypervisorAsset:
 		return conf.HypervisorPath, nil
 	case firmwareAsset:
@@ -337,6 +343,16 @@ func (conf *HypervisorConfig) CustomImageAsset() bool {
 	return conf.isCustomAsset(imageAsset)
 }
 
+// InitrdAssetPath returns the guest initrd path
+func (conf *HypervisorConfig) InitrdAssetPath() (string, error) {
+	return conf.assetPath(initrdAsset)
+}
+
+// CustomInitrdAsset returns true if the initrd asset is a custom one, false otherwise.
+func (conf *HypervisorConfig) CustomInitrdAsset() bool {
+	return conf.isCustomAsset(initrdAsset)
+}
+
 // HypervisorAssetPath returns the VM hypervisor path
 func (conf *HypervisorConfig) HypervisorAssetPath() (string, error) {
 	return conf.assetPath(hypervisorAsset)

virtcontainers/pkg/annotations/annotations.go

@@ -25,6 +25,9 @@ const (
 	// ImagePath is a pod annotation for passing a per container path pointing at the guest image that will run in the container VM.
 	ImagePath = vcAnnotationsPrefix + "ImagePath"
 
+	// InitrdPath is a pod annotation for passing a per container path pointing at the guest initrd image that will run in the container VM.
+	InitrdPath = vcAnnotationsPrefix + "InitrdPath"
+
 	// HypervisorPath is a pod annotation for passing a per container path pointing at the hypervisor that will run the container VM.
 	HypervisorPath = vcAnnotationsPrefix + "HypervisorPath"
 
@@ -37,6 +40,9 @@ const (
 	// ImageHash is an pod annotation for passing a container guest image SHA-512 hash value.
 	ImageHash = vcAnnotationsPrefix + "ImageHash"
 
+	// InitrdHash is an pod annotation for passing a container guest initrd SHA-512 hash value.
+	InitrdHash = vcAnnotationsPrefix + "InitrdHash"
+
 	// HypervisorHash is an pod annotation for passing a container hypervisor binary SHA-512 hash value.
 	HypervisorHash = vcAnnotationsPrefix + "HypervisorHash"
 

virtcontainers/pkg/oci/utils.go

@@ -447,6 +447,7 @@ func addAssetAnnotations(ocispec CompatOCISpec, config *vc.PodConfig) {
 	assetAnnotations := []string{
 		vcAnnotations.KernelPath,
 		vcAnnotations.ImagePath,
+		vcAnnotations.InitrdPath,
 		vcAnnotations.KernelHash,
 		vcAnnotations.ImageHash,
 		vcAnnotations.AssetHashType,

virtcontainers/pod.go

@@ -551,7 +551,16 @@ func createAssets(podConfig *PodConfig) error {
 		return err
 	}
 
-	for _, a := range []*asset{kernel, image} {
+	initrd, err := newAsset(podConfig, initrdAsset)
+	if err != nil {
+		return err
+	}
+
+	if image != nil && initrd != nil {
+		return fmt.Errorf("%s and %s cannot be both set", imageAsset, initrdAsset)
+	}
+
+	for _, a := range []*asset{kernel, image, initrd} {
 		if err := podConfig.HypervisorConfig.addCustomAsset(a); err != nil {
 			return err
 		}

virtcontainers/qemu.go

@@ -284,9 +284,15 @@ func (q *qemu) createPod(podConfig PodConfig) error {
 		return err
 	}
 
+	initrdPath, err := q.config.InitrdAssetPath()
+	if err != nil {
+		return err
+	}
+
 	kernel := govmmQemu.Kernel{
-		Path:   kernelPath,
-		Params: q.kernelParameters(),
+		Path:       kernelPath,
+		InitrdPath: initrdPath,
+		Params:     q.kernelParameters(),
 	}
 
 	rtc := govmmQemu.RTC{
@@ -336,14 +342,18 @@ func (q *qemu) createPod(podConfig PodConfig) error {
 	devices = q.arch.append9PVolumes(devices, podConfig.Volumes)
 	devices = q.arch.appendConsole(devices, q.getPodConsole(podConfig.ID))
 
-	imagePath, err := q.config.ImageAssetPath()
-	if err != nil {
-		return err
-	}
+	if initrdPath == "" {
+		imagePath, err := q.config.ImageAssetPath()
+		if err != nil {
+			return err
+		}
 
-	devices, err = q.arch.appendImage(devices, imagePath)
-	if err != nil {
-		return err
+		if imagePath != "" {
+			devices, err = q.arch.appendImage(devices, imagePath)
+			if err != nil {
+				return err
+			}
+		}
 	}
 
 	if q.config.BlockDeviceDriver == VirtioBlock {

virtcontainers/qemu_test.go

@@ -32,6 +32,7 @@ func newQemuConfig() HypervisorConfig {
 	return HypervisorConfig{
 		KernelPath:        testQemuKernelPath,
 		ImagePath:         testQemuImagePath,
+		InitrdPath:        testQemuInitrdPath,
 		HypervisorPath:    testQemuPath,
 		DefaultVCPUs:      defaultVCPUs,
 		DefaultMemSz:      defaultMemSzMiB,

virtcontainers/virtcontainers_test.go

@@ -30,6 +30,7 @@ import (
 const testPodID = "7f49d00d-1995-4156-8c79-5f5ab24ce138"
 const testContainerID = "containerID"
 const testKernel = "kernel"
+const testInitrd = "initrd"
 const testImage = "image"
 const testHypervisor = "hypervisor"
 const testBundle = "bundle"
@@ -45,6 +46,7 @@ var podDirLock = ""
 var podFileState = ""
 var podFileLock = ""
 var testQemuKernelPath = ""
+var testQemuInitrdPath = ""
 var testQemuImagePath = ""
 var testQemuPath = ""
 var testHyperstartCtlSocket = ""
@@ -135,6 +137,7 @@ func TestMain(m *testing.M) {
 	podFileLock = filepath.Join(runStoragePath, testPodID, lockFileName)
 
 	testQemuKernelPath = filepath.Join(testDir, testKernel)
+	testQemuInitrdPath = filepath.Join(testDir, testInitrd)
 	testQemuImagePath = filepath.Join(testDir, testImage)
 	testQemuPath = filepath.Join(testDir, testHypervisor)