nvidia-container-toolkit/pkg/nvcdi/transform/merged-device.go
Evan Lezar 709e27bf4b Fix implicit memory aliasing in for loop
Signed-off-by: Evan Lezar <elezar@nvidia.com>
2023-10-24 20:11:34 +02:00

127 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 transform
import (
"fmt"
"github.com/NVIDIA/nvidia-container-toolkit/internal/edits"
"github.com/container-orchestrated-devices/container-device-interface/pkg/cdi"
"github.com/container-orchestrated-devices/container-device-interface/pkg/parser"
"github.com/container-orchestrated-devices/container-device-interface/specs-go"
)
const (
allDeviceName = "all"
)
type mergedDevice struct {
name string
skipIfExists bool
simplifier Transformer
}
var _ Transformer = (*mergedDevice)(nil)
// MergedDeviceOption is a function that configures a merged device
type MergedDeviceOption func(*mergedDevice)
// WithName sets the name of the merged device
func WithName(name string) MergedDeviceOption {
return func(m *mergedDevice) {
m.name = name
}
}
// WithSkipIfExists sets whether to skip adding the merged device if it already exists
func WithSkipIfExists(skipIfExists bool) MergedDeviceOption {
return func(m *mergedDevice) {
m.skipIfExists = skipIfExists
}
}
// NewMergedDevice creates a transformer with the specified options
func NewMergedDevice(opts ...MergedDeviceOption) (Transformer, error) {
m := &mergedDevice{}
for _, opt := range opts {
opt(m)
}
if m.name == "" {
m.name = allDeviceName
}
m.simplifier = NewSimplifier()
if err := parser.ValidateDeviceName(m.name); err != nil {
return nil, fmt.Errorf("invalid device name %q: %v", m.name, err)
}
return m, nil
}
// Transform adds a merged device to the spec
func (m mergedDevice) Transform(spec *specs.Spec) error {
if spec == nil {
return nil
}
mergedDevice, err := mergeDeviceSpecs(spec.Devices, m.name)
if err != nil {
return fmt.Errorf("failed to generate merged device %q: %v", m.name, err)
}
if mergedDevice == nil {
if m.skipIfExists {
return nil
}
return fmt.Errorf("device %q already exists", m.name)
}
spec.Devices = append(spec.Devices, *mergedDevice)
if err := m.simplifier.Transform(spec); err != nil {
return fmt.Errorf("failed to simplify spec after merging device %q: %v", m.name, err)
}
return nil
}
// mergeDeviceSpecs creates a device with the specified name which combines the edits from the previous devices.
// If a device of the specified name already exists, no device is created and nil is returned.
func mergeDeviceSpecs(deviceSpecs []specs.Device, mergedDeviceName string) (*specs.Device, error) {
for _, d := range deviceSpecs {
if d.Name == mergedDeviceName {
return nil, nil
}
}
mergedEdits := edits.NewContainerEdits()
for _, d := range deviceSpecs {
d := d
edit := cdi.ContainerEdits{
ContainerEdits: &d.ContainerEdits,
}
mergedEdits.Append(&edit)
}
merged := specs.Device{
Name: mergedDeviceName,
ContainerEdits: *mergedEdits.ContainerEdits,
}
return &merged, nil
}