static void locate_record_ext()

in block/dasd_eckd.c [385:525]

• 135 lines of code
• 29 McCabe index (conditional complexity)

static void locate_record_ext(struct ccw1 *ccw, struct LRE_eckd_data *data,
			      unsigned int trk, unsigned int rec_on_trk,
			      int count, int cmd, struct dasd_device *device,
			      unsigned int reclen, unsigned int tlf)
{
	struct dasd_eckd_private *private = device->private;
	int sector;
	int dn, d;

	if (ccw) {
		ccw->cmd_code = DASD_ECKD_CCW_LOCATE_RECORD_EXT;
		ccw->flags = 0;
		if (cmd == DASD_ECKD_CCW_WRITE_FULL_TRACK)
			ccw->count = 22;
		else
			ccw->count = 20;
		ccw->cda = (__u32)__pa(data);
	}

	memset(data, 0, sizeof(*data));
	sector = 0;
	if (rec_on_trk) {
		switch (private->rdc_data.dev_type) {
		case 0x3390:
			dn = ceil_quot(reclen + 6, 232);
			d = 9 + ceil_quot(reclen + 6 * (dn + 1), 34);
			sector = (49 + (rec_on_trk - 1) * (10 + d)) / 8;
			break;
		case 0x3380:
			d = 7 + ceil_quot(reclen + 12, 32);
			sector = (39 + (rec_on_trk - 1) * (8 + d)) / 7;
			break;
		}
	}
	data->sector = sector;
	/* note: meaning of count depends on the operation
	 *	 for record based I/O it's the number of records, but for
	 *	 track based I/O it's the number of tracks
	 */
	data->count = count;
	switch (cmd) {
	case DASD_ECKD_CCW_WRITE_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_READ_HOME_ADDRESS:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_WRITE_RECORD_ZERO:
		data->operation.orientation = 0x1;
		data->operation.operation = 0x03;
		data->count++;
		break;
	case DASD_ECKD_CCW_READ_RECORD_ZERO:
		data->operation.orientation = 0x3;
		data->operation.operation = 0x16;
		data->count++;
		break;
	case DASD_ECKD_CCW_WRITE:
	case DASD_ECKD_CCW_WRITE_MT:
	case DASD_ECKD_CCW_WRITE_KD:
	case DASD_ECKD_CCW_WRITE_KD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x01;
		break;
	case DASD_ECKD_CCW_WRITE_CKD:
	case DASD_ECKD_CCW_WRITE_CKD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x03;
		break;
	case DASD_ECKD_CCW_WRITE_FULL_TRACK:
		data->operation.orientation = 0x0;
		data->operation.operation = 0x3F;
		data->extended_operation = 0x11;
		data->length = 0;
		data->extended_parameter_length = 0x02;
		if (data->count > 8) {
			data->extended_parameter[0] = 0xFF;
			data->extended_parameter[1] = 0xFF;
			data->extended_parameter[1] <<= (16 - count);
		} else {
			data->extended_parameter[0] = 0xFF;
			data->extended_parameter[0] <<= (8 - count);
			data->extended_parameter[1] = 0x00;
		}
		data->sector = 0xFF;
		break;
	case DASD_ECKD_CCW_WRITE_TRACK_DATA:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;	/* not tlf, as one might think */
		data->operation.operation = 0x3F;
		data->extended_operation = 0x23;
		break;
	case DASD_ECKD_CCW_READ:
	case DASD_ECKD_CCW_READ_MT:
	case DASD_ECKD_CCW_READ_KD:
	case DASD_ECKD_CCW_READ_KD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_READ_CKD:
	case DASD_ECKD_CCW_READ_CKD_MT:
		data->auxiliary.length_valid = 0x1;
		data->length = reclen;
		data->operation.operation = 0x16;
		break;
	case DASD_ECKD_CCW_READ_COUNT:
		data->operation.operation = 0x06;
		break;
	case DASD_ECKD_CCW_READ_TRACK:
		data->operation.orientation = 0x1;
		data->operation.operation = 0x0C;
		data->extended_parameter_length = 0;
		data->sector = 0xFF;
		break;
	case DASD_ECKD_CCW_READ_TRACK_DATA:
		data->auxiliary.length_valid = 0x1;
		data->length = tlf;
		data->operation.operation = 0x0C;
		break;
	case DASD_ECKD_CCW_ERASE:
		data->length = reclen;
		data->auxiliary.length_valid = 0x1;
		data->operation.operation = 0x0b;
		break;
	default:
		DBF_DEV_EVENT(DBF_ERR, device,
			    "fill LRE unknown opcode 0x%x", cmd);
		BUG();
	}
	set_ch_t(&data->seek_addr,
		 trk / private->rdc_data.trk_per_cyl,
		 trk % private->rdc_data.trk_per_cyl);
	data->search_arg.cyl = data->seek_addr.cyl;
	data->search_arg.head = data->seek_addr.head;
	data->search_arg.record = rec_on_trk;
}