vhost-user-blk: Use PciPath type for vhost user devices

VhostUserDeviceAttrs::PCIAddr didn't actually store a PCI address
(DDDD:BB:DD.F), but rather a PCI path.  Use the PciPath type and
rename things to make that clearer.

TestHandleBlockVolume previously used the bizarre value "0001:01"
which is neither a PCI address nor a PCI path for this value.  Change
it to a valid PCI path - it appears the actual value didn't matter for
that test, as long as it was consistent.

Forward port of
3596058c67

fixes #1040

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

src/runtime/virtcontainers/device/config/config.go

@@ -250,9 +250,10 @@ type VhostUserDeviceAttrs struct {
 	CacheSize uint32
 	Cache     string
 
-	// PCIAddr is the PCI address used to identify the slot at which the drive is attached.
-	// It is only meaningful for vhost user block devices
-	PCIAddr string
+	// PCIPath is the PCI path used to identify the slot at which
+	// the drive is attached.  It is only meaningful for vhost
+	// user block devices
+	PCIPath vcTypes.PciPath
 
 	// Block index of the device if assigned
 	Index int

src/runtime/virtcontainers/device/drivers/vhost_user_blk.go

@@ -164,7 +164,7 @@ func (device *VhostUserBlkDevice) Save() persistapi.DeviceState {
 			DevID:      vAttr.DevID,
 			SocketPath: vAttr.SocketPath,
 			Type:       string(vAttr.Type),
-			PCIAddr:    vAttr.PCIAddr,
+			PCIPath:    vAttr.PCIPath,
 			Index:      vAttr.Index,
 		}
 	}
@@ -185,7 +185,7 @@ func (device *VhostUserBlkDevice) Load(ds persistapi.DeviceState) {
 		DevID:      dev.DevID,
 		SocketPath: dev.SocketPath,
 		Type:       config.DeviceType(dev.Type),
-		PCIAddr:    dev.PCIAddr,
+		PCIPath:    dev.PCIPath,
 		Index:      dev.Index,
 	}
 }

src/runtime/virtcontainers/kata_agent.go

@@ -1099,7 +1099,7 @@ func (k *kataAgent) appendVhostUserBlkDevice(dev ContainerDevice, c *Container)
 	kataDevice := &grpc.Device{
 		ContainerPath: dev.ContainerPath,
 		Type:          kataBlkDevType,
-		Id:            d.PCIAddr,
+		Id:            d.PCIPath.String(),
 	}
 
 	return kataDevice
@@ -1467,7 +1467,7 @@ func (k *kataAgent) handleVhostUserBlkVolume(c *Container, m Mount, device api.D
 	}
 
 	vol.Driver = kataBlkDevType
-	vol.Source = d.PCIAddr
+	vol.Source = d.PCIPath.String()
 	vol.Fstype = "bind"
 	vol.Options = []string{"bind"}
 	vol.MountPoint = m.Destination

src/runtime/virtcontainers/kata_agent_test.go

@@ -353,7 +353,8 @@ func TestHandleBlockVolume(t *testing.T) {
 	vDestination := "/VhostUserBlk/destination"
 	bDestination := "/DeviceBlock/destination"
 	dDestination := "/DeviceDirectBlock/destination"
-	vPCIAddr := "0001:01"
+	vPCIPath, err := vcTypes.PciPathFromString("01/02")
+	assert.NoError(t, err)
 	bPCIPath, err := vcTypes.PciPathFromString("03/04")
 	assert.NoError(t, err)
 	dPCIPath, err := vcTypes.PciPathFromString("04/05")
@@ -362,7 +363,7 @@ func TestHandleBlockVolume(t *testing.T) {
 	bDev := drivers.NewBlockDevice(&config.DeviceInfo{ID: bDevID})
 	dDev := drivers.NewBlockDevice(&config.DeviceInfo{ID: dDevID})
 
-	vDev.VhostUserDeviceAttrs = &config.VhostUserDeviceAttrs{PCIAddr: vPCIAddr}
+	vDev.VhostUserDeviceAttrs = &config.VhostUserDeviceAttrs{PCIPath: vPCIPath}
 	bDev.BlockDrive = &config.BlockDrive{PCIPath: bPCIPath}
 	dDev.BlockDrive = &config.BlockDrive{PCIPath: dPCIPath}
 
@@ -413,7 +414,7 @@ func TestHandleBlockVolume(t *testing.T) {
 		Fstype:     "bind",
 		Options:    []string{"bind"},
 		Driver:     kataBlkDevType,
-		Source:     vPCIAddr,
+		Source:     vPCIPath.String(),
 	}
 	bStorage := &pb.Storage{
 		MountPoint: bDestination,
@@ -511,7 +512,7 @@ func TestAppendVhostUserBlkDevices(t *testing.T) {
 			},
 			VhostUserDeviceAttrs: &config.VhostUserDeviceAttrs{
 				Type:    config.VhostUserBlk,
-				PCIAddr: testPCIPath.String(),
+				PCIPath: testPCIPath,
 			},
 		},
 	}

src/runtime/virtcontainers/persist/api/device.go

@@ -73,9 +73,9 @@ type VhostUserDeviceAttrs struct {
 	// MacAddress is only meaningful for vhost user net device
 	MacAddress string
 
-	// PCIAddr is the PCI address used to identify the slot at which the drive is attached.
+	// PCIPath is the PCI path used to identify the slot at which the drive is attached.
 	// It is only meaningful for vhost user block devices
-	PCIAddr string
+	PCIPath vcTypes.PciPath
 
 	// Block index of the device if assigned
 	Index int

src/runtime/virtcontainers/qemu.go

@@ -1351,8 +1351,15 @@ func (q *qemu) hotplugAddVhostUserBlkDevice(vAttr *config.VhostUserDeviceAttrs,
 		}
 	}()
 
-	// PCI address is in the format bridge-addr/device-addr eg. "03/02"
-	vAttr.PCIAddr = fmt.Sprintf("%02x", bridge.Addr) + "/" + addr
+	bridgeSlot, err := vcTypes.PciSlotFromInt(bridge.Addr)
+	if err != nil {
+		return err
+	}
+	devSlot, err := vcTypes.PciSlotFromString(addr)
+	if err != nil {
+		return err
+	}
+	vAttr.PCIPath, err = vcTypes.PciPathFromSlots(bridgeSlot, devSlot)
 
 	if err = q.qmpMonitorCh.qmp.ExecutePCIVhostUserDevAdd(q.qmpMonitorCh.ctx, driver, devID, vAttr.DevID, addr, bridge.ID); err != nil {
 		return err