code: func (b *hostPathMounter) SetUp(fsGroup *int64) error {
  	err := validation.ValidatePathNoBacksteps(b.GetPath())
  	if err != nil {
  		return fmt.Errorf("invalid HostPath `%s`: %v", b.GetPath(), err)
  	}
  
  	if *b.pathType == v1.HostPathUnset {
  		return nil
  	}
  	return checkType(b.GetPath(), b.pathType, b.mounter)
  }
docs: // SetUp does nothing.