runtime: add functions to handle ImageGuestPull to storage

Add functions to handle ImageGuestPull of KataVirtualVolume.

Signed-off-by: ChengyuZhu6 <chengyu.zhu@intel.com>

src/runtime/virtcontainers/container.go

@@ -821,9 +821,6 @@ func (c *Container) createVirtualVolumeDevices() ([]config.DeviceInfo, error) {
 					return nil, err
 				}
 				deviceInfos = append(deviceInfos, *di)
-			} else if virtVolume.VolumeType == types.KataVirtualVolumeImageGuestPullType {
-				///TODO implement the logic with pulling image in the guest.
-				continue
 			}
 		}
 	}

src/runtime/virtcontainers/fs_share_linux.go

@@ -472,6 +472,11 @@ func handleVirtualVolume(c *Container) ([]*grpc.Storage, string, error) {
 						break
 					}
 				}
+			} else if virtVolume.VolumeType == types.KataVirtualVolumeImageGuestPullType {
+				vol, err = handleVirtualVolumeStorageObject(c, "", virtVolume)
+				if err != nil {
+					return nil, "", err
+				}
 			}
 			if vol != nil {
 				volumes = append(volumes, vol)
@@ -521,7 +526,7 @@ func (f *FilesystemShare) ShareRootFilesystem(ctx context.Context, c *Container)
 
 	// In the confidential computing, there is no Image information on the host,
 	// so there is no Rootfs.Target.
-	if f.sandbox.config.ServiceOffload && c.rootFs.Target == "" {
+	if f.sandbox.config.ServiceOffload && c.rootFs.Target == "" && !HasOptionPrefix(c.rootFs.Options, VirtualVolumePrefix) {
 		return &SharedFile{
 			containerStorages: nil,
 			guestPath:         rootfsGuestPath,

src/runtime/virtcontainers/kata_agent.go

@@ -1575,6 +1575,34 @@ func handleDmVerityBlockVolume(driverType, source string, verityInfo *types.DmVe
 	return vol, nil
 }
 
+func handleImageGuestPullBlockVolume(c *Container, virtualVolumeInfo *types.KataVirtualVolume, vol *grpc.Storage) (*grpc.Storage, error) {
+	container_annotations := c.GetAnnotations()
+	container_type := container_annotations["io.kubernetes.cri.container-type"]
+	if virtualVolumeInfo.Source == "" {
+		var image_ref string
+		if container_type == "sandbox" {
+			image_ref = "pause"
+		} else {
+			image_ref = container_annotations["io.kubernetes.cri.image-name"]
+			if image_ref == "" {
+				return nil, fmt.Errorf("Failed to get image name from annotations")
+			}
+		}
+		virtualVolumeInfo.Source = image_ref
+		virtualVolumeInfo.ImagePull.Metadata = container_annotations
+	}
+
+	no, err := json.Marshal(virtualVolumeInfo.ImagePull)
+	if err != nil {
+		return nil, err
+	}
+	vol.Driver = types.KataVirtualVolumeImageGuestPullType
+	vol.DriverOptions = append(vol.DriverOptions, types.KataVirtualVolumeImageGuestPullType+"="+string(no))
+	vol.Source = virtualVolumeInfo.Source
+	vol.Fstype = typeOverlayFS
+	return vol, nil
+}
+
 func handleBlockVolume(c *Container, device api.Device) (*grpc.Storage, error) {
 	vol := &grpc.Storage{}
 
@@ -1631,8 +1659,13 @@ func handleVirtualVolumeStorageObject(c *Container, blockDeviceId string, virtVo
 			}
 		}
 	} else if virtVolume.VolumeType == types.KataVirtualVolumeImageGuestPullType {
-		///TODO implement the logic with pulling image in the guest.
+		var err error
-		return nil, nil
+		vol = &grpc.Storage{}
+		vol, err = handleImageGuestPullBlockVolume(c, virtVolume, vol)
+		vol.MountPoint = filepath.Join("/run/kata-containers/", c.id, c.rootfsSuffix)
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	return vol, nil