Add EnableCDI() method to engine.Interface

This change adds an EnableCDI method to the container engine config files and
Updates the 'nvidia-ctk runtime configure' command to use this new method.

Signed-off-by: Christopher Desiniotis <cdesiniotis@nvidia.com>

cmd/nvidia-ctk/runtime/configure/configure.go

@@ -292,9 +292,8 @@ func (m command) configureConfigFile(c *cli.Context, config *config) error {
 		return fmt.Errorf("unable to update config: %v", err)
 	}
 
-	err = enableCDI(config, cfg)
-	if err != nil {
-		return fmt.Errorf("failed to enable CDI in %s: %w", config.runtime, err)
+	if config.cdi.enabled {
+		cfg.EnableCDI()
 	}
 
 	outputPath := config.getOutputConfigPath()
@@ -354,19 +353,3 @@ func (m *command) configureOCIHook(c *cli.Context, config *config) error {
 	}
 	return nil
 }
-
-// enableCDI enables the use of CDI in the corresponding container engine
-func enableCDI(config *config, cfg engine.Interface) error {
-	if !config.cdi.enabled {
-		return nil
-	}
-	switch config.runtime {
-	case "containerd":
-		cfg.Set("enable_cdi", true)
-	case "docker":
-		cfg.Set("features", map[string]bool{"cdi": true})
-	default:
-		return fmt.Errorf("enabling CDI in %s is not supported", config.runtime)
-	}
-	return nil
-}

pkg/config/engine/api.go

@@ -20,6 +20,7 @@ package engine
 type Interface interface {
 	AddRuntime(string, string, bool) error
 	DefaultRuntime() string
+	EnableCDI()
 	GetRuntimeConfig(string) (RuntimeConfig, error)
 	RemoveRuntime(string) error
 	Save(string) (int64, error)

pkg/config/engine/containerd/config.go

@@ -111,6 +111,11 @@ func (c Config) DefaultRuntime() string {
 	return ""
 }
 
+// EnableCDI sets the enable_cdi field in the Containerd config to true.
+func (c *Config) EnableCDI() {
+	c.Set("enable_cdi", true)
+}
+
 // RemoveRuntime removes a runtime from the docker config
 func (c *Config) RemoveRuntime(name string) error {
 	if c == nil || c.Tree == nil {

pkg/config/engine/containerd/config_v1.go

@@ -165,3 +165,7 @@ func (c *ConfigV1) GetRuntimeConfig(name string) (engine.RuntimeConfig, error) {
 		tree: runtimeData,
 	}, nil
 }
+
+func (c *ConfigV1) EnableCDI() {
+	c.Set("enable_cdi", true)
+}

pkg/config/engine/crio/crio.go

@@ -153,6 +153,9 @@ func (c *Config) GetRuntimeConfig(name string) (engine.RuntimeConfig, error) {
 	}, nil
 }
 
+// EnableCDI is a no-op for CRI-O since it always enabled where supported.
+func (c *Config) EnableCDI() {}
+
 // CommandLineSource returns the CLI-based crio config loader
 func CommandLineSource(hostRoot string) toml.Loader {
 	return toml.LoadFirst(

pkg/config/engine/docker/docker.go

@@ -103,6 +103,11 @@ func (c Config) DefaultRuntime() string {
 	return r
 }
 
+// EnableCDI sets features.cdi to true in the docker config.
+func (c *Config) EnableCDI() {
+	c.Set("features", map[string]bool{"cdi": true})
+}
+
 // RemoveRuntime removes a runtime from the docker config
 func (c *Config) RemoveRuntime(name string) error {
 	if c == nil {