virtcontainers: kata_agent: Add virtio-scsi support

This commit enables the support of virtio-scsi for block devices
used as root filesystem or as devices passed through the VM to be
used directly from the container.

Fixes #56

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

virtcontainers/kata_agent.go

@@ -51,6 +51,7 @@ var (
 	vsockSocketScheme           = "vsock"
 	kata9pDevType               = "9p"
 	kataBlkDevType              = "blk"
+	kataSCSIDevType             = "scsi"
 	sharedDir9pOptions          = []string{"trans=virtio,version=9p2000.L", "nodev"}
 )
 
@@ -588,11 +589,17 @@ func (k *kataAgent) appendDevices(deviceList []*grpc.Device, devices []Device) [
 		}
 
 		kataDevice := &grpc.Device{
-			Type:          kataBlkDevType,
-			VmPath:        d.VirtPath,
 			ContainerPath: d.DeviceInfo.ContainerPath,
 		}
 
+		if d.SCSIAddr == "" {
+			kataDevice.Type = kataBlkDevType
+			kataDevice.VmPath = d.VirtPath
+		} else {
+			kataDevice.Type = kataSCSIDevType
+			kataDevice.Id = d.SCSIAddr
+		}
+
 		deviceList = append(deviceList, kataDevice)
 	}
 
@@ -621,20 +628,30 @@ func (k *kataAgent) createContainer(pod *Pod, c *Container) (*Process, error) {
 
 	if c.state.Fstype != "" {
 		// This is a block based device rootfs.
-		// driveName is the predicted virtio-block guest name (the vd* in /dev/vd*).
-		driveName, err := getVirtDriveName(c.state.BlockIndex)
-		if err != nil {
-			return nil, err
-		}
-		virtPath := filepath.Join(devPath, driveName)
 
-		// Create a new device with empty ContainerPath so that we get
+		// Pass a drive name only in case of virtio-blk driver.
-		// the device being waited for by the agent inside the VM,
+		// If virtio-scsi driver, the agent will be able to find the
-		// without trying to match and update it into the OCI spec list
+		// device based on the provided address.
-		// of actual devices. The device corresponding to the rootfs is
+		if pod.config.HypervisorConfig.BlockDeviceDriver == VirtioBlock {
-		// a very specific case.
+			// driveName is the predicted virtio-block guest name (the vd* in /dev/vd*).
-		rootfs.Driver = kataBlkDevType
+			driveName, err := getVirtDriveName(c.state.BlockIndex)
-		rootfs.Source = virtPath
+			if err != nil {
+				return nil, err
+			}
+			virtPath := filepath.Join(devPath, driveName)
+
+			rootfs.Driver = kataBlkDevType
+			rootfs.Source = virtPath
+		} else {
+			scsiAddr, err := getSCSIAddress(c.state.BlockIndex)
+			if err != nil {
+				return nil, err
+			}
+
+			rootfs.Driver = kataSCSIDevType
+			rootfs.Source = scsiAddr
+		}
+
 		rootfs.MountPoint = rootPathParent
 		rootfs.Fstype = c.state.Fstype