rem: struct scsi_unit *scsi_units, int n_scsi_units)
add: struct scsi_unit *units, int n_units)
context: lookup_scsi_unit (int bus, int id, int lun,		  struct scsi_unit *scsi_units, int n_scsi_units){	int i;	for (i = 0; i < n_scsi_units; i++) {		if (scsi_units[i].bus == bus &&		    scsi_units[i].id == id &&		    scsi_units[i].lun == lun) {			return &scsi_units[i];		}	}	return NULL;}