Device: Support long device names for host path passthrough to VMs

lxd-agent/events.go

@@ -8,6 +8,7 @@ import (
 	"strings"
 
 	"github.com/canonical/lxd/lxd/events"
+	"github.com/canonical/lxd/lxd/instance/instancetype"
 	"github.com/canonical/lxd/lxd/response"
 	"github.com/canonical/lxd/shared"
 	"github.com/canonical/lxd/shared/api"
@@ -27,6 +28,7 @@ type eventsServe struct {
 	d   *Daemon
 }
 
+// Render starts event socket.
 func (r *eventsServe) Render(w http.ResponseWriter) error {
 	return eventsSocket(r.d, r.req, w)
 }
@@ -115,9 +117,10 @@ func eventsProcess(event api.Event) {
 	}
 
 	type deviceEvent struct {
-		Action string            `json:"action"`
-		Config map[string]string `json:"config"`
-		Name   string            `json:"name"`
+		Action string                    `json:"action"`
+		Config map[string]string         `json:"config"`
+		Name   string                    `json:"name"`
+		Mount  instancetype.VMAgentMount `json:"mount"`
 	}
 
 	e := deviceEvent{}
@@ -143,6 +146,9 @@ func eventsProcess(event api.Event) {
 
 	// Attempt to perform the mount.
 	mntSource := fmt.Sprintf("lxd_%s", e.Name)
+	if e.Mount.Source != "" {
+		mntSource = e.Mount.Source
+	}
 
 	_ = os.MkdirAll(e.Config["path"], 0755)
 	_, err = shared.RunCommand("mount", "-t", "virtiofs", mntSource, e.Config["path"])

lxd/device/disk.go

@@ -850,15 +850,15 @@ func (d *disk) startContainer() (*deviceConfig.RunConfig, error) {
 
 // vmVirtfsProxyHelperPaths returns the path for PID file to use with virtfs-proxy-helper process.
 func (d *disk) vmVirtfsProxyHelperPaths() string {
-	pidPath := filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("%s.pid", d.name))
+	pidPath := filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("%s.pid", filesystem.PathNameEncode(d.name)))
 
 	return pidPath
 }
 
 // vmVirtiofsdPaths returns the path for the socket and PID file to use with virtiofsd process.
 func (d *disk) vmVirtiofsdPaths() (sockPath string, pidPath string) {
-	sockPath = filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("virtio-fs.%s.sock", d.name))
-	pidPath = filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("virtio-fs.%s.pid", d.name))
+	sockPath = filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("virtio-fs.%s.sock", filesystem.PathNameEncode(d.name)))
+	pidPath = filepath.Join(d.inst.DevicesPath(), fmt.Sprintf("virtio-fs.%s.pid", filesystem.PathNameEncode(d.name)))
 
 	return sockPath, pidPath
 }
@@ -1114,7 +1114,7 @@ func (d *disk) startVM() (*deviceConfig.RunConfig, error) {
 				// virtfs-proxy-helper 9p share. The 9p share will only be used as a fallback.
 				err = func() error {
 					sockPath, pidPath := d.vmVirtiofsdPaths()
-					logPath := filepath.Join(d.inst.LogPath(), fmt.Sprintf("disk.%s.log", d.name))
+					logPath := filepath.Join(d.inst.LogPath(), fmt.Sprintf("disk.%s.log", filesystem.PathNameEncode(d.name)))
 					_ = os.Remove(logPath) // Remove old log if needed.
 
 					revertFunc, unixListener, err := DiskVMVirtiofsdStart(d.state.OS.ExecPath, d.inst, sockPath, pidPath, logPath, mount.DevPath, rawIDMaps)

lxd/instance/drivers/driver_common.go

@@ -1419,13 +1419,13 @@ func (d *common) devicesRegister(inst instance.Instance) {
 }
 
 // devicesUpdate applies device changes to an instance.
-func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfig.Devices, addDevices deviceConfig.Devices, updateDevices deviceConfig.Devices, oldExpandedDevices deviceConfig.Devices, instanceRunning bool, userRequested bool) error {
+func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfig.Devices, addDevices deviceConfig.Devices, updateDevices deviceConfig.Devices, oldExpandedDevices deviceConfig.Devices, instanceRunning bool, userRequested bool) (devlxdEvents []map[string]any, err error) {
 	revert := revert.New()
 	defer revert.Fail()
 
 	dm, ok := inst.(deviceManager)
 	if !ok {
-		return fmt.Errorf("Instance is not compatible with deviceManager interface")
+		return nil, fmt.Errorf("Instance is not compatible with deviceManager interface")
 	}
 
 	// Remove devices in reverse order to how they were added.
@@ -1446,13 +1446,19 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 			if instanceRunning {
 				err = dm.deviceStop(dev, instanceRunning, "")
 				if err != nil {
-					return fmt.Errorf("Failed to stop device %q: %w", dev.Name(), err)
+					return nil, fmt.Errorf("Failed to stop device %q: %w", dev.Name(), err)
 				}
+
+				devlxdEvents = append(devlxdEvents, map[string]any{
+					"action": "removed",
+					"name":   entry.Name,
+					"config": entry.Config,
+				})
 			}
 
 			err = d.deviceRemove(dev, instanceRunning)
 			if err != nil && err != device.ErrUnsupportedDevType {
-				return fmt.Errorf("Failed to remove device %q: %w", dev.Name(), err)
+				return nil, fmt.Errorf("Failed to remove device %q: %w", dev.Name(), err)
 			}
 		}
 
@@ -1461,7 +1467,7 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 		// this device (as its an actual removal or a device type change).
 		err = d.deviceVolatileReset(entry.Name, entry.Config, addDevices[entry.Name])
 		if err != nil {
-			return fmt.Errorf("Failed to reset volatile data for device %q: %w", entry.Name, err)
+			return nil, fmt.Errorf("Failed to reset volatile data for device %q: %w", entry.Name, err)
 		}
 	}
 
@@ -1475,7 +1481,7 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 			}
 
 			if userRequested {
-				return fmt.Errorf("Failed add validation for device %q: %w", entry.Name, err)
+				return nil, fmt.Errorf("Failed add validation for device %q: %w", entry.Name, err)
 			}
 
 			// If update is non-user requested (i.e from a snapshot restore), there's nothing we can
@@ -1488,7 +1494,7 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 		err = d.deviceAdd(dev, instanceRunning)
 		if err != nil {
 			if userRequested {
-				return fmt.Errorf("Failed to add device %q: %w", dev.Name(), err)
+				return nil, fmt.Errorf("Failed to add device %q: %w", dev.Name(), err)
 			}
 
 			// If update is non-user requested (i.e from a snapshot restore), there's nothing we can
@@ -1501,15 +1507,34 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 		if instanceRunning {
 			err = dev.PreStartCheck()
 			if err != nil {
-				return fmt.Errorf("Failed pre-start check for device %q: %w", dev.Name(), err)
+				return nil, fmt.Errorf("Failed pre-start check for device %q: %w", dev.Name(), err)
 			}
 
-			_, err := dm.deviceStart(dev, instanceRunning)
+			runConf, err := dm.deviceStart(dev, instanceRunning)
 			if err != nil && err != device.ErrUnsupportedDevType {
-				return fmt.Errorf("Failed to start device %q: %w", dev.Name(), err)
+				return nil, fmt.Errorf("Failed to start device %q: %w", dev.Name(), err)
 			}
 
 			revert.Add(func() { _ = dm.deviceStop(dev, instanceRunning, "") })
+
+			event := map[string]any{
+				"action": "added",
+				"name":   entry.Name,
+				"config": entry.Config,
+			}
+
+			if len(runConf.Mounts) > 0 {
+				for _, opt := range runConf.Mounts[0].Opts {
+					if strings.HasPrefix(opt, "mountTag=") {
+						parts := strings.SplitN(opt, "=", 2)
+						event["mount"] = instancetype.VMAgentMount{
+							Source: parts[1],
+						}
+					}
+				}
+			}
+
+			devlxdEvents = append(devlxdEvents, event)
 		}
 	}
 
@@ -1522,7 +1547,7 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 			}
 
 			if userRequested {
-				return fmt.Errorf("Failed update validation for device %q: %w", entry.Name, err)
+				return nil, fmt.Errorf("Failed update validation for device %q: %w", entry.Name, err)
 			}
 
 			// If update is non-user requested (i.e from a snapshot restore), there's nothing we can
@@ -1542,6 +1567,12 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 					if err != nil {
 						l.Error("Failed to stop device after update validation failed", logger.Ctx{"err": err})
 					}
+
+					devlxdEvents = append(devlxdEvents, map[string]any{
+						"action": "updated",
+						"name":   entry.Name,
+						"config": entry.Config,
+					})
 				}
 
 				err = d.deviceRemove(dev, instanceRunning)
@@ -1555,12 +1586,12 @@ func (d *common) devicesUpdate(inst instance.Instance, removeDevices deviceConfi
 
 		err = dev.Update(oldExpandedDevices, instanceRunning)
 		if err != nil {
-			return fmt.Errorf("Failed to update device %q: %w", dev.Name(), err)
+			return nil, fmt.Errorf("Failed to update device %q: %w", dev.Name(), err)
 		}
 	}
 
 	revert.Success()
-	return nil
+	return devlxdEvents, nil
 }
 
 // devicesRemove runs device removal function for each device.

lxd/instance/drivers/driver_lxc.go

@@ -4384,7 +4384,7 @@ func (d *lxc) Update(args db.InstanceArgs, userRequested bool) error {
 	isRunning := d.IsRunning()
 
 	// Use the device interface to apply update changes.
-	err = d.devicesUpdate(d, removeDevices, addDevices, updateDevices, oldExpandedDevices, isRunning, userRequested)
+	devlxdEvents, err := d.devicesUpdate(d, removeDevices, addDevices, updateDevices, oldExpandedDevices, isRunning, userRequested)
 	if err != nil {
 		return err
 	}
@@ -4819,41 +4819,9 @@ func (d *lxc) Update(args db.InstanceArgs, userRequested bool) error {
 			}
 		}
 
-		// Device changes
-		for k, m := range removeDevices {
-			msg := map[string]any{
-				"action": "removed",
-				"name":   k,
-				"config": m,
-			}
-
-			err = d.devlxdEventSend("device", msg)
-			if err != nil {
-				return err
-			}
-		}
-
-		for k, m := range updateDevices {
-			msg := map[string]any{
-				"action": "updated",
-				"name":   k,
-				"config": m,
-			}
-
-			err = d.devlxdEventSend("device", msg)
-			if err != nil {
-				return err
-			}
-		}
-
-		for k, m := range addDevices {
-			msg := map[string]any{
-				"action": "added",
-				"name":   k,
-				"config": m,
-			}
-
-			err = d.devlxdEventSend("device", msg)
+		// Device events.
+		for _, event := range devlxdEvents {
+			err = d.devlxdEventSend("device", event)
 			if err != nil {
 				return err
 			}