code: func (d *Driver) Cleanup() error {
  	err := d.subvolDisableQuota()
  	umountErr := mount.Unmount(d.home)
  
  	// in case we have two errors, prefer the one from disableQuota()
  	if err != nil {
  		return err
  	}
  
  	if umountErr != nil {
  		return umountErr
  	}
  
  	return nil
  }
docs: // Cleanup unmounts the home directory.