code: func ValidateVolumeAttachmentV1(volumeAttachment *storage.VolumeAttachment) field.ErrorList {
  	allErrs := apivalidation.ValidateCSIDriverName(volumeAttachment.Spec.Attacher, field.NewPath("spec.attacher"))
  
  	if volumeAttachment.Spec.Source.PersistentVolumeName != nil {
  		pvName := *volumeAttachment.Spec.Source.PersistentVolumeName
  		for _, msg := range apivalidation.ValidatePersistentVolumeName(pvName, false) {
  			allErrs = append(allErrs, field.Invalid(field.NewPath("spec.source.persistentVolumeName"), pvName, msg))
  		}
  	}
  	return allErrs
  }
docs: // ValidateVolumeAttachmentV1 validates a v1/VolumeAttachment. It contains only extra checks missing in
  // ValidateVolumeAttachment.