nvidia-container-toolkit/pkg/nvcdi/workarounds-device-folder-permissions.go
Evan Lezar d4e21fdd10 Add devRoot option to CDI api
A driverRoot defines both the driver library root and the
root for device nodes. In the case of preinstalled drivers or
the driver container, these are equal, but in cases such as GKE
they do not match. In this case, drivers are extracted to a folder
and devices exist at the root /.

The changes here add a devRoot option to the nvcdi API that allows the
parent of /dev to be specified explicitly.

Signed-off-by: Evan Lezar <elezar@nvidia.com>
2023-11-20 21:29:35 +01:00

119 lines
3.3 KiB
Go

/**
# Copyright (c) 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 nvcdi
import (
"fmt"
"path/filepath"
"github.com/NVIDIA/nvidia-container-toolkit/internal/discover"
"github.com/NVIDIA/nvidia-container-toolkit/internal/logger"
)
type deviceFolderPermissions struct {
logger logger.Interface
devRoot string
nvidiaCTKPath string
devices discover.Discover
}
var _ discover.Discover = (*deviceFolderPermissions)(nil)
// newDeviceFolderPermissionHookDiscoverer creates a discoverer that can be used to update the permissions for the parent folders of nested device nodes from the specified set of device specs.
// This works around an issue with rootless podman when using crun as a low-level runtime.
// See https://github.com/containers/crun/issues/1047
// The nested devices that are applicable to the NVIDIA GPU devices are:
// - DRM devices at /dev/dri/*
// - NVIDIA Caps devices at /dev/nvidia-caps/*
func newDeviceFolderPermissionHookDiscoverer(logger logger.Interface, devRoot string, nvidiaCTKPath string, devices discover.Discover) discover.Discover {
d := &deviceFolderPermissions{
logger: logger,
devRoot: devRoot,
nvidiaCTKPath: nvidiaCTKPath,
devices: devices,
}
return d
}
// Devices are empty for this discoverer
func (d *deviceFolderPermissions) Devices() ([]discover.Device, error) {
return nil, nil
}
// Hooks returns a set of hooks that sets the file mode to 755 of parent folders for nested device nodes.
func (d *deviceFolderPermissions) Hooks() ([]discover.Hook, error) {
folders, err := d.getDeviceSubfolders()
if err != nil {
return nil, fmt.Errorf("failed to get device subfolders: %v", err)
}
if len(folders) == 0 {
return nil, nil
}
args := []string{"--mode", "755"}
for _, folder := range folders {
args = append(args, "--path", folder)
}
hook := discover.CreateNvidiaCTKHook(
d.nvidiaCTKPath,
"chmod",
args...,
)
return []discover.Hook{hook}, nil
}
func (d *deviceFolderPermissions) getDeviceSubfolders() ([]string, error) {
// For now we only consider the following special case paths
allowedPaths := map[string]bool{
"/dev/dri": true,
"/dev/nvidia-caps": true,
}
devices, err := d.devices.Devices()
if err != nil {
return nil, fmt.Errorf("failed to get devices: %v", err)
}
var folders []string
seen := make(map[string]bool)
for _, device := range devices {
df := filepath.Dir(device.Path)
if seen[df] {
continue
}
// We only consider the special case paths
if !allowedPaths[df] {
continue
}
folders = append(folders, df)
seen[df] = true
if len(folders) == len(allowedPaths) {
break
}
}
return folders, nil
}
// Mounts are empty for this discoverer
func (d *deviceFolderPermissions) Mounts() ([]discover.Mount, error) {
return nil, nil
}