func (b *Provider) DestroyVolume(vol volume.Volume) error {
zvol, err := b.owns(vol)
if err != nil {
return err
}
if vol.IsSnapshot() {
if err := syscall.Unmount(vol.Location(), 0); err != nil {
return err
}
os.Remove(vol.Location())
}
if err := zvol.dataset.Destroy(zfs.DestroyForceUmount); err != nil {
for i := 0; i < 5 && err != nil && IsDatasetBusyError(err); i++ {
// sometimes zfs will claim to be busy as if files are still open even when all container processes are dead.
// usually this goes away, so retry a few times.
time.Sleep(1 * time.Second)
err = zvol.dataset.Destroy(zfs.DestroyForceUmount)
}
if err != nil {
return err
}
}
os.Remove(zvol.basemount)
delete(b.volumes, vol.Info().ID)
return nil
}
func (p *Provider) ForkVolume(vol volume.Volume) (volume.Volume, error) {
zvol, err := p.owns(vol)
if err != nil {
return nil, err
}
if !vol.IsSnapshot() {
return nil, fmt.Errorf("can only fork a snapshot")
}
id := random.UUID()
info := &volume.Info{ID: id, Type: vol.Info().Type}
v2 := &zfsVolume{
info: info,
provider: zvol.provider,
basemount: p.mountPath(info),
}
cloneID := fmt.Sprintf("%s/%s", zvol.provider.dataset.Name, id)
v2.dataset, err = zvol.dataset.Clone(cloneID, map[string]string{
"mountpoint": v2.basemount,
})
if err != nil {
return nil, fmt.Errorf("could not fork volume: %s", err)
}
p.volumes[id] = v2
return v2, nil
}
func (b *Provider) SendSnapshot(vol volume.Volume, haves []json.RawMessage, output io.Writer) error {
zvol, err := b.owns(vol)
if err != nil {
return err
}
if !vol.IsSnapshot() {
return fmt.Errorf("can only send a snapshot")
}
// zfs recv can only really accept snapshots that apply to the current tip
var latestRemote string
if haves != nil && len(haves) > 0 {
have := &zfsHaves{}
if err := json.Unmarshal(haves[len(haves)-1], have); err == nil {
latestRemote = have.SnapID
}
}
// look for intersection of existing snapshots on this volume; if so do incremental
parentName := strings.SplitN(zvol.dataset.Name, "@", 2)[0]
parentDataset, err := zfs.GetDataset(parentName)
if err != nil {
return err
}
snapshots, err := parentDataset.Snapshots()
if err != nil {
return err
}
// we can fly incremental iff the latest snap on the remote is available here
useIncremental := false
if latestRemote != "" {
for _, snap := range snapshots {
if strings.SplitN(snap.Name, "@", 2)[1] == latestRemote {
useIncremental = true
break
}
}
}
// at last, send:
if useIncremental {
sendCmd := exec.Command("zfs", "send", "-i", latestRemote, zvol.dataset.Name)
sendCmd.Stdout = output
return sendCmd.Run()
}
return zvol.dataset.SendSnapshot(output)
}