// Attaches a disk specified by a volume.GCEPersistentDisk to the current kubelet.
// Mounts the disk to it's global path.
func (util *GCEDiskUtil) AttachAndMountDisk(pd *gcePersistentDisk, globalPDPath string) error {
gce, err := cloudprovider.GetCloudProvider("gce", nil)
if err != nil {
return err
}
flags := uintptr(0)
if pd.readOnly {
flags = mount.FlagReadOnly
}
if err := gce.(*gce_cloud.GCECloud).AttachDisk(pd.pdName, pd.readOnly); err != nil {
return err
}
devicePath := path.Join("/dev/disk/by-id/", "google-"+pd.pdName)
if pd.partition != "" {
devicePath = devicePath + "-part" + pd.partition
}
//TODO(jonesdl) There should probably be better method than busy-waiting here.
numTries := 0
for {
_, err := os.Stat(devicePath)
if err == nil {
break
}
if err != nil && !os.IsNotExist(err) {
return err
}
numTries++
if numTries == 10 {
return errors.New("Could not attach disk: Timeout after 10s")
}
time.Sleep(time.Second)
}
// Only mount the PD globally once.
mountpoint, err := mount.IsMountPoint(globalPDPath)
if err != nil {
if os.IsNotExist(err) {
if err := os.MkdirAll(globalPDPath, 0750); err != nil {
return err
}
mountpoint = false
} else {
return err
}
}
if !mountpoint {
err = pd.diskMounter.Mount(devicePath, globalPDPath, pd.fsType, flags, "")
if err != nil {
os.Remove(globalPDPath)
return err
}
}
return nil
}
// Unmounts the bind mount, and detaches the disk only if the PD
// resource was the last reference to that disk on the kubelet.
func (pd *gcePersistentDisk) TearDownAt(dir string) error {
mountpoint, err := mount.IsMountPoint(dir)
if err != nil {
return err
}
if !mountpoint {
return os.Remove(dir)
}
refs, err := mount.GetMountRefs(pd.mounter, dir)
if err != nil {
return err
}
// Unmount the bind-mount inside this pod
if err := pd.mounter.Unmount(dir, 0); err != nil {
return err
}
// If len(refs) is 1, then all bind mounts have been removed, and the
// remaining reference is the global mount. It is safe to detach.
if len(refs) == 1 {
// pd.pdName is not initially set for volume-cleaners, so set it here.
pd.pdName = path.Base(refs[0])
if err := pd.manager.DetachDisk(pd); err != nil {
return err
}
}
mountpoint, mntErr := mount.IsMountPoint(dir)
if mntErr != nil {
glog.Errorf("isMountpoint check failed: %v", mntErr)
return err
}
if !mountpoint {
if err := os.Remove(dir); err != nil {
return err
}
}
return nil
}
func (m *realMountDetector) GetMountMedium(path string) (storageMedium, bool, error) {
isMnt, err := mount.IsMountPoint(path)
if err != nil {
return 0, false, fmt.Errorf("IsMountPoint(%q): %v", path, err)
}
buf := syscall.Statfs_t{}
if err := syscall.Statfs(path, &buf); err != nil {
return 0, false, fmt.Errorf("statfs(%q): %v", path, err)
}
if buf.Type == linuxTmpfsMagic {
return mediumMemory, isMnt, nil
}
return mediumUnknown, isMnt, nil
}
// SetUpAt attaches the disk and bind mounts to the volume path.
func (pd *gcePersistentDisk) SetUpAt(dir string) error {
if pd.legacyMode {
return fmt.Errorf("legacy mode: can not create new instances")
}
// TODO: handle failed mounts here.
mountpoint, err := mount.IsMountPoint(dir)
glog.V(4).Infof("PersistentDisk set up: %s %v %v", dir, mountpoint, err)
if err != nil && !os.IsNotExist(err) {
return err
}
if mountpoint {
return nil
}
globalPDPath := makeGlobalPDName(pd.plugin.host, pd.pdName)
if err := pd.manager.AttachAndMountDisk(pd, globalPDPath); err != nil {
return err
}
flags := uintptr(0)
if pd.readOnly {
flags = mount.FlagReadOnly
}
if err := os.MkdirAll(dir, 0750); err != nil {
// TODO: we should really eject the attach/detach out into its own control loop.
detachDiskLogError(pd)
return err
}
// Perform a bind mount to the full path to allow duplicate mounts of the same PD.
err = pd.mounter.Mount(globalPDPath, dir, "", mount.FlagBind|flags, "")
if err != nil {
mountpoint, mntErr := mount.IsMountPoint(dir)
if mntErr != nil {
glog.Errorf("isMountpoint check failed: %v", mntErr)
return err
}
if mountpoint {
if mntErr = pd.mounter.Unmount(dir, 0); mntErr != nil {
glog.Errorf("Failed to unmount: %v", mntErr)
return err
}
mountpoint, mntErr := mount.IsMountPoint(dir)
if mntErr != nil {
glog.Errorf("isMountpoint check failed: %v", mntErr)
return err
}
if mountpoint {
// This is very odd, we don't expect it. We'll try again next sync loop.
glog.Errorf("%s is still mounted, despite call to unmount(). Will try again next sync loop.", dir)
return err
}
}
os.Remove(dir)
// TODO: we should really eject the attach/detach out into its own control loop.
detachDiskLogError(pd)
return err
}
return nil
}