k8s-csi-s3/pkg/s3/util.go

106 lines
2.4 KiB
Go

package s3
import (
"errors"
"fmt"
"io/ioutil"
"os"
"os/exec"
"strings"
"syscall"
"time"
"github.com/mitchellh/go-ps"
"k8s.io/kubernetes/pkg/util/mount"
"github.com/golang/glog"
)
func waitForProcess(p *os.Process, backoff int) error {
if backoff == 20 {
return fmt.Errorf("Timeout waiting for PID %v to end", p.Pid)
}
cmdLine, err := getCmdLine(p.Pid)
if err != nil {
glog.Warningf("Error checking cmdline of PID %v, assuming it is dead: %s", p.Pid, err)
return nil
}
if cmdLine == "" {
// ignore defunct processes
// TODO: debug why this happens in the first place
// seems to only happen on k8s, not on local docker
glog.Warning("Fuse process seems dead, returning")
return nil
}
if err := p.Signal(syscall.Signal(0)); err != nil {
glog.Warningf("Fuse process does not seem active or we are unprivileged: %s", err)
return nil
}
glog.Infof("Fuse process with PID %v still active, waiting...", p.Pid)
time.Sleep(time.Duration(backoff*100) * time.Millisecond)
return waitForProcess(p, backoff+1)
}
func waitForMount(path string, timeout time.Duration) error {
var elapsed time.Duration
var interval = 10 * time.Millisecond
for {
notMount, err := mount.New("").IsNotMountPoint(path)
if err != nil {
return err
}
if !notMount {
return nil
}
time.Sleep(interval)
elapsed = elapsed + interval
if elapsed >= timeout {
return errors.New("Timeout waiting for mount")
}
}
}
func findFuseMountProcess(path string) (*os.Process, error) {
processes, err := ps.Processes()
if err != nil {
return nil, err
}
for _, p := range processes {
cmdLine, err := getCmdLine(p.Pid())
if err != nil {
glog.Errorf("Unable to get cmdline of PID %v: %s", p.Pid(), err)
continue
}
if strings.Contains(cmdLine, path) {
glog.Infof("Found matching pid %v on path %s", p.Pid(), path)
return os.FindProcess(p.Pid())
}
}
return nil, nil
}
func getCmdLine(pid int) (string, error) {
cmdLineFile := fmt.Sprintf("/proc/%v/cmdline", pid)
cmdLine, err := ioutil.ReadFile(cmdLineFile)
if err != nil {
return "", err
}
return string(cmdLine), nil
}
func createLoopDevice(device string) error {
if _, err := os.Stat(device); !os.IsNotExist(err) {
return nil
}
args := []string{
device,
"b", "7", "0",
}
cmd := exec.Command("mknod", args...)
out, err := cmd.CombinedOutput()
if err != nil {
return fmt.Errorf("Error configuring loop device: %s", out)
}
return nil
}