Files
kubernetes/pkg/volume/util/volumepathhandler/volume_path_handler_linux.go
Davanum Srinivas 954996e231 Move from glog to klog
- Move from the old github.com/golang/glog to k8s.io/klog
- klog as explicit InitFlags() so we add them as necessary
- we update the other repositories that we vendor that made a similar
change from glog to klog
  * github.com/kubernetes/repo-infra
  * k8s.io/gengo/
  * k8s.io/kube-openapi/
  * github.com/google/cadvisor
- Entirely remove all references to glog
- Fix some tests by explicit InitFlags in their init() methods

Change-Id: I92db545ff36fcec83afe98f550c9e630098b3135
2018-11-10 07:50:31 -05:00

109 lines
2.9 KiB
Go

// +build linux
/*
Copyright 2018 The Kubernetes Authors.
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 volumepathhandler
import (
"errors"
"fmt"
"os"
"os/exec"
"strings"
"k8s.io/klog"
)
// AttachFileDevice takes a path to a regular file and makes it available as an
// attached block device.
func (v VolumePathHandler) AttachFileDevice(path string) (string, error) {
blockDevicePath, err := v.GetLoopDevice(path)
if err != nil && err.Error() != ErrDeviceNotFound {
return "", err
}
// If no existing loop device for the path, create one
if blockDevicePath == "" {
klog.V(4).Infof("Creating device for path: %s", path)
blockDevicePath, err = makeLoopDevice(path)
if err != nil {
return "", err
}
}
return blockDevicePath, nil
}
// GetLoopDevice returns the full path to the loop device associated with the given path.
func (v VolumePathHandler) GetLoopDevice(path string) (string, error) {
_, err := os.Stat(path)
if os.IsNotExist(err) {
return "", errors.New(ErrDeviceNotFound)
}
if err != nil {
return "", fmt.Errorf("not attachable: %v", err)
}
args := []string{"-j", path}
cmd := exec.Command(losetupPath, args...)
out, err := cmd.CombinedOutput()
if err != nil {
klog.V(2).Infof("Failed device discover command for path %s: %v %s", path, err, out)
return "", err
}
return parseLosetupOutputForDevice(out)
}
func makeLoopDevice(path string) (string, error) {
args := []string{"-f", "--show", path}
cmd := exec.Command(losetupPath, args...)
out, err := cmd.CombinedOutput()
if err != nil {
klog.V(2).Infof("Failed device create command for path: %s %v %s ", path, err, out)
return "", err
}
return parseLosetupOutputForDevice(out)
}
// RemoveLoopDevice removes specified loopback device
func (v VolumePathHandler) RemoveLoopDevice(device string) error {
args := []string{"-d", device}
cmd := exec.Command(losetupPath, args...)
out, err := cmd.CombinedOutput()
if err != nil {
if _, err := os.Stat(device); os.IsNotExist(err) {
return nil
}
klog.V(2).Infof("Failed to remove loopback device: %s: %v %s", device, err, out)
return err
}
return nil
}
func parseLosetupOutputForDevice(output []byte) (string, error) {
if len(output) == 0 {
return "", errors.New(ErrDeviceNotFound)
}
// losetup returns device in the format:
// /dev/loop1: [0073]:148662 (/dev/sda)
device := strings.TrimSpace(strings.SplitN(string(output), ":", 2)[0])
if len(device) == 0 {
return "", errors.New(ErrDeviceNotFound)
}
return device, nil
}