Merge pull request #345 from elezar/allow-skip-of-device-nodes

Add --create-device-nodes option to toolkit config

tools/container/toolkit/toolkit.go

@@ -70,6 +70,8 @@ type options struct {
 	cdiVendor    string
 	cdiClass     string
 
+	createDeviceNodes cli.StringSlice
+
 	acceptNVIDIAVisibleDevicesWhenUnprivileged bool
 	acceptNVIDIAVisibleDevicesAsVolumeMounts   bool
 
@@ -224,6 +226,13 @@ func main() {
 			Hidden:      true,
 			Destination: &opts.ignoreErrors,
 		},
+		&cli.StringSliceFlag{
+			Name:        "create-device-nodes",
+			Usage:       "(Only applicable with --cdi-enabled) specifies which device nodes should be created. If any one of the options is set to '' or 'none', no device nodes will be created.",
+			Value:       cli.NewStringSlice("control"),
+			Destination: &opts.createDeviceNodes,
+			EnvVars:     []string{"CREATE_DEVICE_NODES"},
+		},
 	}
 
 	// Update the subcommand flags with the common subcommand flags
@@ -252,6 +261,29 @@ func validateOptions(c *cli.Context, opts *options) error {
 	opts.cdiVendor = vendor
 	opts.cdiClass = class
 
+	if opts.cdiEnabled && opts.cdiOutputDir == "" {
+		log.Warning("Skipping CDI spec generation (no output directory specified)")
+		opts.cdiEnabled = false
+	}
+
+	isDisabled := false
+	for _, mode := range opts.createDeviceNodes.Value() {
+		if mode != "" && mode != "none" && mode != "control" {
+			return fmt.Errorf("invalid --create-device-nodes value: %v", mode)
+		}
+		if mode == "" || mode == "none" {
+			isDisabled = true
+			break
+		}
+	}
+	if !opts.cdiEnabled && !isDisabled {
+		log.Info("disabling device node creation since --cdi-enabled=false")
+		isDisabled = true
+	}
+	if isDisabled {
+		opts.createDeviceNodes = *cli.NewStringSlice()
+	}
+
 	return nil
 }
 
@@ -330,7 +362,21 @@ func Install(cli *cli.Context, opts *options) error {
 		log.Errorf("Ignoring error: %v", fmt.Errorf("error installing NVIDIA container toolkit config: %v", err))
 	}
 
-	return generateCDISpec(opts, nvidiaCTKPath)
+	err = createDeviceNodes(opts)
+	if err != nil && !opts.ignoreErrors {
+		return fmt.Errorf("error creating device nodes: %v", err)
+	} else if err != nil {
+		log.Errorf("Ignoring error: %v", fmt.Errorf("error creating device nodes: %v", err))
+	}
+
+	err = generateCDISpec(opts, nvidiaCTKPath)
+	if err != nil && !opts.ignoreErrors {
+		return fmt.Errorf("error generating CDI specification: %v", err)
+	} else if err != nil {
+		log.Errorf("Ignoring error: %v", fmt.Errorf("error generating CDI specification: %v", err))
+	}
+
+	return nil
 }
 
 // installContainerLibraries locates and installs the libraries that are part of
@@ -677,27 +723,37 @@ func createDirectories(dir ...string) error {
 	return nil
 }
 
-// generateCDISpec generates a CDI spec for use in managemnt containers
-func generateCDISpec(opts *options, nvidiaCTKPath string) error {
-	if !opts.cdiEnabled {
-		return nil
-	}
-	if opts.cdiOutputDir == "" {
-		log.Info("Skipping CDI spec generation (no output directory specified)")
+func createDeviceNodes(opts *options) error {
+	modes := opts.createDeviceNodes.Value()
+	if len(modes) == 0 {
 		return nil
 	}
 
-	log.Infof("Creating control device nodes at %v", opts.DriverRootCtrPath)
 	devices, err := nvdevices.New(
 		nvdevices.WithDevRoot(opts.DriverRootCtrPath),
 	)
 	if err != nil {
 		return fmt.Errorf("failed to create library: %v", err)
 	}
-	if err := devices.CreateNVIDIAControlDevices(); err != nil {
-		return fmt.Errorf("failed to create control device nodes: %v", err)
+
+	for _, mode := range modes {
+		log.Infof("Creating %v device nodes at %v", mode, opts.DriverRootCtrPath)
+		if mode != "control" {
+			log.Warningf("Unrecognised device mode: %v", mode)
+			continue
+		}
+		if err := devices.CreateNVIDIAControlDevices(); err != nil {
+			return fmt.Errorf("failed to create control device nodes: %v", err)
+		}
 	}
+	return nil
+}
 
+// generateCDISpec generates a CDI spec for use in managemnt containers
+func generateCDISpec(opts *options, nvidiaCTKPath string) error {
+	if !opts.cdiEnabled {
+		return nil
+	}
 	log.Info("Generating CDI spec for management containers")
 	cdilib, err := nvcdi.New(
 		nvcdi.WithMode(nvcdi.ModeManagement),