Add modifier to inject Tegra platform files

This change adds a modifier to that injects the tegra platform files
* /etc/nv_tegra_release
* /sys/devices/soc0/family

allowing these files to be used for platform detection in a containerized
context such as the GPU device plugin.

Signed-off-by: Evan Lezar <elezar@nvidia.com>

cmd/nvidia-container-runtime/runtime_factory.go

@@ -77,10 +77,16 @@ func newSpecModifier(logger *logrus.Logger, cfg *config.Config, ociSpec oci.Spec
 		return nil, err
 	}
 
+	tegraModifier, err := modifier.NewTegraPlatformFiles(logger)
+	if err != nil {
+		return nil, err
+	}
+
 	modifiers := modifier.Merge(
 		modeModifier,
 		gdsModifier,
 		mofedModifier,
+		tegraModifier,
 	)
 	return modifiers, nil
 }

internal/modifier/tegra.go

@@ -0,0 +1,45 @@
+/**
+# Copyright (c) 2022, 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 modifier
+
+import (
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/discover"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/info"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/lookup"
+	"github.com/NVIDIA/nvidia-container-toolkit/internal/oci"
+	"github.com/sirupsen/logrus"
+)
+
+// NewTegraPlatformFiles creates a modifier to inject the Tegra platform files into a container.
+func NewTegraPlatformFiles(logger *logrus.Logger) (oci.SpecModifier, error) {
+	isTegra, _ := info.IsTegraSystem()
+	if !isTegra {
+		return nil, nil
+	}
+
+	tegraSystemMounts := discover.NewMounts(
+		logger,
+		lookup.NewFileLocator(logger, ""),
+		"",
+		[]string{
+			"/etc/nv_tegra_release",
+			"/sys/devices/soc0/family",
+		},
+	)
+
+	return NewModifierFromDiscoverer(logger, tegraSystemMounts)
+}