[no-relnote] Move control device nodes to separate file

Signed-off-by: Evan Lezar <[email protected]>

Author: elezar

internal/system/nvdevices/control-device-nodes.go

@@ -0,0 +1,99 @@
+/**
+# Copyright (c) 2025, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+**/
+
+package nvdevices
+
+import (
+	"fmt"
+	"path/filepath"
+	"strings"
+
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/info/proc/devices"
+)
+
+// A controlDeviceNode represents an NVIDIA devices node for control or meta devices.
+// Such device nodes are typically required regardless of which GPU is being accessed.
+type controlDeviceNode string
+
+func (c controlDeviceNode) path() string {
+	return filepath.Join("dev", string(c))
+}
+
+// CreateNVIDIAControlDevices creates the NVIDIA control device nodes at the configured devRoot.
+func (m *Interface) CreateNVIDIAControlDevices() error {
+	controlNodes := []controlDeviceNode{"nvidiactl", "nvidia-modeset", "nvidia-uvm", "nvidia-uvm-tools"}
+	for _, node := range controlNodes {
+		if err := m.createControlDeviceNode(node); err != nil {
+			return fmt.Errorf("failed to create device node %s: %w", node, err)
+		}
+	}
+	return nil
+}
+
+// createControlDeviceNode creates the specified NVIDIA device node at the configured devRoot.
+func (m *Interface) createControlDeviceNode(node controlDeviceNode) error {
+	if !strings.HasPrefix(string(node), "nvidia") {
+		return fmt.Errorf("invalid device node %q: %w", node, errInvalidDeviceNode)
+	}
+
+	major, err := m.controlDeviceNodeMajor(node)
+	if err != nil {
+		return fmt.Errorf("failed to determine major: %w", err)
+	}
+
+	minor, err := m.controlDeviceNodeMinor(node)
+	if err != nil {
+		return fmt.Errorf("failed to determine minor: %w", err)
+	}
+
+	return m.createDeviceNode(node.path(), int(major), int(minor))
+}
+
+// controlDeviceNodeMajor returns the major number for the specified NVIDIA control device node.
+// If the device node is not supported, an error is returned.
+func (m *Interface) controlDeviceNodeMajor(node controlDeviceNode) (int64, error) {
+	var valid bool
+	var major devices.Major
+	switch node {
+	case "nvidia-uvm", "nvidia-uvm-tools":
+		major, valid = m.Get(devices.NVIDIAUVM)
+	case "nvidia-modeset", "nvidiactl":
+		major, valid = m.Get(devices.NVIDIAGPU)
+	}
+
+	if valid {
+		return int64(major), nil
+	}
+
+	return 0, errInvalidDeviceNode
+}
+
+// controlDeviceNodeMinor returns the minor number for the specified NVIDIA control device node.
+// If the device node is not supported, an error is returned.
+func (m *Interface) controlDeviceNodeMinor(node controlDeviceNode) (int64, error) {
+	switch node {
+	case "nvidia-modeset":
+		return devices.NVIDIAModesetMinor, nil
+	case "nvidia-uvm-tools":
+		return devices.NVIDIAUVMToolsMinor, nil
+	case "nvidia-uvm":
+		return devices.NVIDIAUVMMinor, nil
+	case "nvidiactl":
+		return devices.NVIDIACTLMinor, nil
+	}
+
+	return 0, errInvalidDeviceNode
+}

internal/system/nvdevices/devices.go

@@ -20,7 +20,6 @@ import (
 	"errors"
 	"fmt"
 	"path/filepath"
-	"strings"
 
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/info/proc/devices"
 	"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
@@ -70,77 +69,9 @@ func New(opts ...Option) (*Interface, error) {
 	return i, nil
 }
 
-// CreateNVIDIAControlDevices creates the NVIDIA control device nodes at the configured devRoot.
-func (m *Interface) CreateNVIDIAControlDevices() error {
-	controlNodes := []string{"nvidiactl", "nvidia-modeset", "nvidia-uvm", "nvidia-uvm-tools"}
-	for _, node := range controlNodes {
-		err := m.CreateNVIDIADevice(node)
-		if err != nil {
-			return fmt.Errorf("failed to create device node %s: %w", node, err)
-		}
-	}
-	return nil
-}
-
-// CreateNVIDIADevice creates the specified NVIDIA device node at the configured devRoot.
-func (m *Interface) CreateNVIDIADevice(node string) error {
-	node = filepath.Base(node)
-	if !strings.HasPrefix(node, "nvidia") {
-		return fmt.Errorf("invalid device node %q: %w", node, errInvalidDeviceNode)
-	}
-
-	major, err := m.Major(node)
-	if err != nil {
-		return fmt.Errorf("failed to determine major: %w", err)
-	}
-
-	minor, err := m.Minor(node)
-	if err != nil {
-		return fmt.Errorf("failed to determine minor: %w", err)
-	}
-
-	return m.createDeviceNode(filepath.Join("dev", node), int(major), int(minor))
-}
-
 // createDeviceNode creates the specified device node with the require major and minor numbers.
 // If a devRoot is configured, this is prepended to the path.
 func (m *Interface) createDeviceNode(path string, major int, minor int) error {
 	path = filepath.Join(m.devRoot, path)
 	return m.Mknode(path, major, minor)
 }
-
-// Major returns the major number for the specified NVIDIA device node.
-// If the device node is not supported, an error is returned.
-func (m *Interface) Major(node string) (int64, error) {
-	var valid bool
-	var major devices.Major
-	switch node {
-	case "nvidia-uvm", "nvidia-uvm-tools":
-		major, valid = m.Get(devices.NVIDIAUVM)
-	case "nvidia-modeset", "nvidiactl":
-		major, valid = m.Get(devices.NVIDIAGPU)
-	}
-
-	if valid {
-		return int64(major), nil
-	}
-
-	return 0, errInvalidDeviceNode
-}
-
-// Minor returns the minor number for the specified NVIDIA device node.
-// If the device node is not supported, an error is returned.
-func (m *Interface) Minor(node string) (int64, error) {
-	switch node {
-	case "nvidia-modeset":
-		return devices.NVIDIAModesetMinor, nil
-	case "nvidia-uvm-tools":
-		return devices.NVIDIAUVMToolsMinor, nil
-	case "nvidia-uvm":
-		return devices.NVIDIAUVMMinor, nil
-	case "nvidiactl":
-		return devices.NVIDIACTLMinor, nil
-	}
-
-	return 0, errInvalidDeviceNode
-}