virtcontainers: Enable virtio-fs on s390x

Allow and configure vhost-user-fs devices (virtio-fs) on s390x. As a
consequence, appendVhostUserDevice now takes a context, which affects
its signature for other architectures.

Fixes: #1753

Signed-off-by: Jakob Naucke <jakob.naucke@ibm.com>

src/runtime/virtcontainers/qemu.go

@@ -1924,7 +1924,7 @@ func (q *qemu) addDevice(ctx context.Context, devInfo interface{}, devType devic
 			vhostDev.SocketPath = sockPath
 			vhostDev.DevID = id
 
-			q.qemuConfig.Devices, err = q.arch.appendVhostUserDevice(q.qemuConfig.Devices, vhostDev)
+			q.qemuConfig.Devices, err = q.arch.appendVhostUserDevice(ctx, q.qemuConfig.Devices, vhostDev)
 		} else {
 			q.Logger().WithField("volume-type", "virtio-9p").Info("adding volume")
 			q.qemuConfig.Devices, err = q.arch.append9PVolume(ctx, q.qemuConfig.Devices, v)
@@ -1939,7 +1939,7 @@ func (q *qemu) addDevice(ctx context.Context, devInfo interface{}, devType devic
 	case config.BlockDrive:
 		q.qemuConfig.Devices, err = q.arch.appendBlockDevice(ctx, q.qemuConfig.Devices, v)
 	case config.VhostUserDeviceAttrs:
-		q.qemuConfig.Devices, err = q.arch.appendVhostUserDevice(q.qemuConfig.Devices, v)
+		q.qemuConfig.Devices, err = q.arch.appendVhostUserDevice(ctx, q.qemuConfig.Devices, v)
 	case config.VFIODev:
 		q.qemuConfig.Devices = q.arch.appendVFIODevice(q.qemuConfig.Devices, v)
 	default:

src/runtime/virtcontainers/qemu_arch_base.go

@@ -96,7 +96,7 @@ type qemuArch interface {
 	appendBlockDevice(ctx context.Context, devices []govmmQemu.Device, drive config.BlockDrive) ([]govmmQemu.Device, error)
 
 	// appendVhostUserDevice appends a vhost user device to devices
-	appendVhostUserDevice(devices []govmmQemu.Device, drive config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error)
+	appendVhostUserDevice(ctx context.Context, devices []govmmQemu.Device, drive config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error)
 
 	// appendVFIODevice appends a VFIO device to devices
 	appendVFIODevice(devices []govmmQemu.Device, vfioDevice config.VFIODev) []govmmQemu.Device
@@ -633,7 +633,7 @@ func (q *qemuArchBase) appendBlockDevice(_ context.Context, devices []govmmQemu.
 	return devices, nil
 }
 
-func (q *qemuArchBase) appendVhostUserDevice(devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
+func (q *qemuArchBase) appendVhostUserDevice(ctx context.Context, devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
 	qemuVhostUserDevice := govmmQemu.VhostUserDevice{}
 
 	switch attr.Type {

src/runtime/virtcontainers/qemu_arch_base_test.go

@@ -224,7 +224,7 @@ func testQemuArchBaseAppend(t *testing.T, structure interface{}, expected []govm
 	case config.VFIODev:
 		devices = qemuArchBase.appendVFIODevice(devices, s)
 	case config.VhostUserDeviceAttrs:
-		devices, err = qemuArchBase.appendVhostUserDevice(devices, s)
+		devices, err = qemuArchBase.appendVhostUserDevice(context.Background(), devices, s)
 	}
 
 	assert.NoError(err)

src/runtime/virtcontainers/qemu_s390x.go

@@ -13,6 +13,7 @@ import (
 	govmmQemu "github.com/kata-containers/govmm/qemu"
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/device/config"
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/types"
+	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/utils"
 )
 
 type qemuS390x struct {
@@ -152,10 +153,33 @@ func (q *qemuS390x) appendCCWBlockDevice(ctx context.Context, devices []govmmQem
 	return devices, nil
 }
 
-// appendVhostUserDevice throws an error if vhost devices are tried to be used.
+func (q *qemuS390x) appendVhostUserDevice(ctx context.Context, devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
-// See issue https://github.com/kata-containers/runtime/issues/659
+	if attr.Type != config.VhostUserFS {
-func (q *qemuS390x) appendVhostUserDevice(devices []govmmQemu.Device, attr config.VhostUserDeviceAttrs) ([]govmmQemu.Device, error) {
+		return devices, fmt.Errorf("vhost-user device of type %s not supported on s390x, only vhost-user-fs-ccw is supported", attr.Type)
-	return nil, fmt.Errorf("No vhost-user devices supported on s390x")
+	}
+
+	addr, b, err := q.addDeviceToBridge(ctx, attr.DevID, types.CCW)
+	if err != nil {
+		return devices, fmt.Errorf("Failed to append vhost user device: %s", err)
+	}
+	var devno string
+	devno, err = b.AddressFormatCCW(addr)
+	if err != nil {
+		return devices, fmt.Errorf("Failed to append vhost user device: %s", err)
+	}
+
+	qemuVhostUserDevice := govmmQemu.VhostUserDevice{
+		SocketPath:    attr.SocketPath,
+		CharDevID:     utils.MakeNameID("char", attr.DevID, maxDevIDSize),
+		TypeDevID:     utils.MakeNameID("fs", attr.DevID, maxDevIDSize),
+		Tag:           attr.Tag,
+		CacheSize:     attr.CacheSize,
+		VhostUserType: govmmQemu.VhostUserFS,
+		DevNo:         devno,
+	}
+
+	devices = append(devices, qemuVhostUserDevice)
+	return devices, nil
 }
 
 // supportGuestMemoryHotplug return false for s390x architecture. The pc-dimm backend device for s390x

src/runtime/virtcontainers/qemu_s390x_test.go

@@ -6,11 +6,14 @@
 package virtcontainers
 
 import (
+	"context"
 	"fmt"
 	"testing"
 
 	govmmQemu "github.com/kata-containers/govmm/qemu"
 	"github.com/stretchr/testify/assert"
+
+	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/device/config"
 )
 
 func newTestQemu(assert *assert.Assertions, machineType string) qemuArch {
@@ -54,15 +57,47 @@ func TestQemuS390xMemoryTopology(t *testing.T) {
 }
 
 func TestQemuS390xAppendVhostUserDevice(t *testing.T) {
-	macAddress := "00:11:22:33:44:55:66"
-	qemu := qemuS390x{}
 	assert := assert.New(t)
+	qemu := newTestQemu(assert, QemuCCWVirtio)
 
+	// test devices that should not work
+	for _, deviceType := range []config.DeviceType{config.VhostUserSCSI, config.VhostUserNet, config.VhostUserBlk} {
 		vhostUserDevice := config.VhostUserDeviceAttrs{
-		Type:       config.VhostUserNet,
+			Type: deviceType,
-		MacAddress: macAddress,
+		}
+		_, err := qemu.appendVhostUserDevice(context.Background(), nil, vhostUserDevice)
+		assert.Error(err)
 	}
 
-	_, err := qemu.appendVhostUserDevice(nil, vhostUserDevice)
+	// test vhost user fs (virtio-fs)
-	assert.Error(err)
+	socketPath := "nonexistentpath.sock"
+	id := "deadbeef"
+	tag := "shared"
+	var cacheSize uint32 = 0
+
+	expected := []govmmQemu.Device{
+		govmmQemu.VhostUserDevice{
+			SocketPath:    socketPath,
+			CharDevID:     fmt.Sprintf("char-%s", id),
+			TypeDevID:     fmt.Sprintf("fs-%s", id),
+			Tag:           tag,
+			CacheSize:     cacheSize,
+			VhostUserType: govmmQemu.VhostUserFS,
+			DevNo:         "fe.0.0001",
+		},
+	}
+
+	vhostUserDevice := config.VhostUserDeviceAttrs{
+		DevID:      id,
+		SocketPath: socketPath,
+		Type:       config.VhostUserFS,
+		Tag:        tag,
+		CacheSize:  cacheSize,
+	}
+
+	var devices []govmmQemu.Device
+	devices, err := qemu.appendVhostUserDevice(context.Background(), devices, vhostUserDevice)
+
+	assert.NoError(err)
+	assert.Equal(devices, expected)
 }