tape_34xx.c

linux-2.6.15.6

	struct list_head *	sbid_list;
	struct tape_34xx_sbid *	sbid;
	struct list_head *	l;

	/*
	 * immediately return if there is no list at all or the block to add
	 * is located in segment 1 of wrap 0 because this position is used
	 * if no hardware position data is supplied.
	 */
	sbid_list = (struct list_head *) device->discdata;
	if (!sbid_list || (bid.segment < 2 && bid.wrap == 0))
		return;

	/*
	 * Search the position where to insert the new entry. Hardware
	 * acceleration uses only the segment and wrap number. So we
	 * need only one entry for a specific wrap/segment combination.
	 * If there is a block with a lower number but the same hard-
	 * ware position data we just update the block number in the
	 * existing entry.
	 */
	list_for_each(l, sbid_list) {
		sbid = list_entry(l, struct tape_34xx_sbid, list);

		if (
			(sbid->bid.segment == bid.segment) &&
			(sbid->bid.wrap    == bid.wrap)
		) {
			if (bid.block < sbid->bid.block)
				sbid->bid = bid;
			else return;
			break;
		}

		/* Sort in according to logical block number. */
		if (bid.block < sbid->bid.block) {
			tape_34xx_append_new_sbid(bid, l->prev);
			break;
		}
	}
	/* List empty or new block bigger than last entry. */
	if (l == sbid_list)
		tape_34xx_append_new_sbid(bid, l->prev);

	DBF_LH(4, "Current list is:\n");
	list_for_each(l, sbid_list) {
		sbid = list_entry(l, struct tape_34xx_sbid, list);
		DBF_LH(4, "%d:%03d@%05d\n",
			sbid->bid.wrap,
			sbid->bid.segment,
			sbid->bid.block
		);
	}
}

/*
 * Delete all entries from the search block ID list that belong to tape blocks
 * equal or higher than the given number.
 */
static void
tape_34xx_delete_sbid_from(struct tape_device *device, int from)
{
	struct list_head *	sbid_list;
	struct tape_34xx_sbid *	sbid;
	struct list_head *	l;
	struct list_head *	n;

	sbid_list = (struct list_head *) device->discdata;
	if (!sbid_list)
		return;

	list_for_each_safe(l, n, sbid_list) {
		sbid = list_entry(l, struct tape_34xx_sbid, list);
		if (sbid->bid.block >= from) {
			DBF_LH(4, "Delete sbid %d:%03d@%05d\n",
				sbid->bid.wrap,
				sbid->bid.segment,
				sbid->bid.block
			);
			list_del(l);
			kfree(sbid);
		}
	}
}

/*
 * Merge hardware position data into a block id.
 */
static void
tape_34xx_merge_sbid(
	struct tape_device *		device,
	struct tape_34xx_block_id *	bid
) {
	struct tape_34xx_sbid *	sbid;
	struct tape_34xx_sbid *	sbid_to_use;
	struct list_head *	sbid_list;
	struct list_head *	l;

	sbid_list = (struct list_head *) device->discdata;
	bid->wrap    = 0;
	bid->segment = 1;

	if (!sbid_list || list_empty(sbid_list))
		return;

	sbid_to_use = NULL;
	list_for_each(l, sbid_list) {
		sbid = list_entry(l, struct tape_34xx_sbid, list);

		if (sbid->bid.block >= bid->block)
			break;
		sbid_to_use = sbid;
	}
	if (sbid_to_use) {
		bid->wrap    = sbid_to_use->bid.wrap;
		bid->segment = sbid_to_use->bid.segment;
		DBF_LH(4, "Use %d:%03d@%05d for %05d\n",
			sbid_to_use->bid.wrap,
			sbid_to_use->bid.segment,
			sbid_to_use->bid.block,
			bid->block
		);
	}
}

static int
tape_34xx_setup_device(struct tape_device * device)
{
	int			rc;
	struct list_head *	discdata;

	DBF_EVENT(6, "34xx device setup\n");
	if ((rc = tape_std_assign(device)) == 0) {
		if ((rc = tape_34xx_medium_sense(device)) != 0) {
			DBF_LH(3, "34xx medium sense returned %d\n", rc);
		}
	}
	discdata = kmalloc(sizeof(struct list_head), GFP_KERNEL);
	if (discdata) {
			INIT_LIST_HEAD(discdata);
			device->discdata = discdata;
	}

	return rc;
}

static void
tape_34xx_cleanup_device(struct tape_device *device)
{
	tape_std_unassign(device);
	
	if (device->discdata) {
		tape_34xx_delete_sbid_from(device, 0);
		kfree(device->discdata);
		device->discdata = NULL;
	}
}


/*
 * MTTELL: Tell block. Return the number of block relative to current file.
 */
static int
tape_34xx_mttell(struct tape_device *device, int mt_count)
{
	struct {
		struct tape_34xx_block_id	cbid;
		struct tape_34xx_block_id	dbid;
	} __attribute__ ((packed)) block_id;
	int rc;

	rc = tape_std_read_block_id(device, (__u64 *) &block_id);
	if (rc)
		return rc;

	tape_34xx_add_sbid(device, block_id.cbid);
	return block_id.cbid.block;
}

/*
 * MTSEEK: seek to the specified block.
 */
static int
tape_34xx_mtseek(struct tape_device *device, int mt_count)
{
	struct tape_request *request;
	struct tape_34xx_block_id *	bid;

	if (mt_count > 0x3fffff) {
		DBF_EXCEPTION(6, "xsee parm\n");
		return -EINVAL;
	}
	request = tape_alloc_request(3, 4);
	if (IS_ERR(request))
		return PTR_ERR(request);

	/* setup ccws */
	request->op = TO_LBL;
	bid         = (struct tape_34xx_block_id *) request->cpdata;
	bid->format = (*device->modeset_byte & 0x08) ?
			TAPE34XX_FMT_3480_XF : TAPE34XX_FMT_3480;
	bid->block  = mt_count;
	tape_34xx_merge_sbid(device, bid);

	tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
	tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
	tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);

	/* execute it */
	return tape_do_io_free(device, request);
}

#ifdef CONFIG_S390_TAPE_BLOCK
/*
 * Tape block read for 34xx.
 */
static struct tape_request *
tape_34xx_bread(struct tape_device *device, struct request *req)
{
	struct tape_request *request;
	struct ccw1 *ccw;
	int count = 0, i;
	unsigned off;
	char *dst;
	struct bio_vec *bv;
	struct bio *bio;
	struct tape_34xx_block_id *	start_block;

	DBF_EVENT(6, "xBREDid:");

	/* Count the number of blocks for the request. */
	rq_for_each_bio(bio, req) {
		bio_for_each_segment(bv, bio, i) {
			count += bv->bv_len >> (TAPEBLOCK_HSEC_S2B + 9);
		}
	}

	/* Allocate the ccw request. */
	request = tape_alloc_request(3+count+1, 8);
	if (IS_ERR(request))
		return request;

	/* Setup ccws. */
	request->op = TO_BLOCK;
	start_block = (struct tape_34xx_block_id *) request->cpdata;
	start_block->block = req->sector >> TAPEBLOCK_HSEC_S2B;
	DBF_EVENT(6, "start_block = %i\n", start_block->block);

	ccw = request->cpaddr;
	ccw = tape_ccw_cc(ccw, MODE_SET_DB, 1, device->modeset_byte);

	/*
	 * We always setup a nop after the mode set ccw. This slot is
	 * used in tape_std_check_locate to insert a locate ccw if the
	 * current tape position doesn't match the start block to be read.
	 * The second nop will be filled with a read block id which is in
	 * turn used by tape_34xx_free_bread to populate the segment bid
	 * table.
	 */
	ccw = tape_ccw_cc(ccw, NOP, 0, NULL);
	ccw = tape_ccw_cc(ccw, NOP, 0, NULL);

	rq_for_each_bio(bio, req) {
		bio_for_each_segment(bv, bio, i) {
			dst = kmap(bv->bv_page) + bv->bv_offset;
			for (off = 0; off < bv->bv_len;
			     off += TAPEBLOCK_HSEC_SIZE) {
				ccw->flags = CCW_FLAG_CC;
				ccw->cmd_code = READ_FORWARD;
				ccw->count = TAPEBLOCK_HSEC_SIZE;
				set_normalized_cda(ccw, (void*) __pa(dst));
				ccw++;
				dst += TAPEBLOCK_HSEC_SIZE;
			}
		}
	}

	ccw = tape_ccw_end(ccw, NOP, 0, NULL);
	DBF_EVENT(6, "xBREDccwg\n");
	return request;
}

static void
tape_34xx_free_bread (struct tape_request *request)
{
	struct ccw1* ccw;

	ccw = request->cpaddr;
	if ((ccw + 2)->cmd_code == READ_BLOCK_ID) {
		struct {
			struct tape_34xx_block_id	cbid;
			struct tape_34xx_block_id	dbid;
		} __attribute__ ((packed)) *rbi_data;

		rbi_data = request->cpdata;

		if (request->device)
			tape_34xx_add_sbid(request->device, rbi_data->cbid);
	}

	/* Last ccw is a nop and doesn't need clear_normalized_cda */
	for (; ccw->flags & CCW_FLAG_CC; ccw++)
		if (ccw->cmd_code == READ_FORWARD)
			clear_normalized_cda(ccw);
	tape_free_request(request);
}

/*
 * check_locate is called just before the tape request is passed to
 * the common io layer for execution. It has to check the current
 * tape position and insert a locate ccw if it doesn't match the
 * start block for the request.
 */
static void
tape_34xx_check_locate(struct tape_device *device, struct tape_request *request)
{
	struct tape_34xx_block_id *	start_block;

	start_block = (struct tape_34xx_block_id *) request->cpdata;
	if (start_block->block == device->blk_data.block_position)
		return;

	DBF_LH(4, "Block seek(%06d+%06d)\n", start_block->block, device->bof);
	start_block->wrap    = 0;
	start_block->segment = 1;
	start_block->format  = (*device->modeset_byte & 0x08) ?
				TAPE34XX_FMT_3480_XF :
				TAPE34XX_FMT_3480;
	start_block->block   = start_block->block + device->bof;
	tape_34xx_merge_sbid(device, start_block);
	tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
	tape_ccw_cc(request->cpaddr + 2, READ_BLOCK_ID, 8, request->cpdata);
}
#endif

/*
 * List of 3480/3490 magnetic tape commands.
 */
static tape_mtop_fn tape_34xx_mtop[TAPE_NR_MTOPS] = {
	[MTRESET]	 = tape_std_mtreset,
	[MTFSF]		 = tape_std_mtfsf,
	[MTBSF]		 = tape_std_mtbsf,
	[MTFSR]		 = tape_std_mtfsr,
	[MTBSR]		 = tape_std_mtbsr,
	[MTWEOF]	 = tape_std_mtweof,
	[MTREW]		 = tape_std_mtrew,
	[MTOFFL]	 = tape_std_mtoffl,
	[MTNOP]		 = tape_std_mtnop,
	[MTRETEN]	 = tape_std_mtreten,
	[MTBSFM]	 = tape_std_mtbsfm,
	[MTFSFM]	 = tape_std_mtfsfm,
	[MTEOM]		 = tape_std_mteom,
	[MTERASE]	 = tape_std_mterase,
	[MTRAS1]	 = NULL,
	[MTRAS2]	 = NULL,
	[MTRAS3]	 = NULL,
	[MTSETBLK]	 = tape_std_mtsetblk,
	[MTSETDENSITY]	 = NULL,
	[MTSEEK]	 = tape_34xx_mtseek,
	[MTTELL]	 = tape_34xx_mttell,
	[MTSETDRVBUFFER] = NULL,
	[MTFSS]		 = NULL,
	[MTBSS]		 = NULL,
	[MTWSM]		 = NULL,
	[MTLOCK]	 = NULL,
	[MTUNLOCK]	 = NULL,
	[MTLOAD]	 = tape_std_mtload,
	[MTUNLOAD]	 = tape_std_mtunload,
	[MTCOMPRESSION]	 = tape_std_mtcompression,
	[MTSETPART]	 = NULL,
	[MTMKPART]	 = NULL
};

/*
 * Tape discipline structure for 3480 and 3490.
 */
static struct tape_discipline tape_discipline_34xx = {
	.owner = THIS_MODULE,
	.setup_device = tape_34xx_setup_device,
	.cleanup_device = tape_34xx_cleanup_device,
	.process_eov = tape_std_process_eov,
	.irq = tape_34xx_irq,
	.read_block = tape_std_read_block,
	.write_block = tape_std_write_block,
#ifdef CONFIG_S390_TAPE_BLOCK
	.bread = tape_34xx_bread,
	.free_bread = tape_34xx_free_bread,
	.check_locate = tape_34xx_check_locate,
#endif
	.ioctl_fn = tape_34xx_ioctl,
	.mtop_array = tape_34xx_mtop
};

static struct ccw_device_id tape_34xx_ids[] = {
	{ CCW_DEVICE_DEVTYPE(0x3480, 0, 0x3480, 0), driver_info: tape_3480},
	{ CCW_DEVICE_DEVTYPE(0x3490, 0, 0x3490, 0), driver_info: tape_3490},
	{ /* end of list */ }
};

static int
tape_34xx_online(struct ccw_device *cdev)
{
	return tape_generic_online(
		cdev->dev.driver_data,
		&tape_discipline_34xx
	);
}

static int
tape_34xx_offline(struct ccw_device *cdev)
{
	return tape_generic_offline(cdev->dev.driver_data);
}

static struct ccw_driver tape_34xx_driver = {
	.name = "tape_34xx",
	.owner = THIS_MODULE,
	.ids = tape_34xx_ids,
	.probe = tape_generic_probe,
	.remove = tape_generic_remove,
	.set_online = tape_34xx_online,
	.set_offline = tape_34xx_offline,
};

static int
tape_34xx_init (void)
{
	int rc;

	TAPE_DBF_AREA = debug_register ( "tape_34xx", 2, 2, 4*sizeof(long));
	debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
#ifdef DBF_LIKE_HELL
	debug_set_level(TAPE_DBF_AREA, 6);
#endif

	DBF_EVENT(3, "34xx init: $Revision: 1.23 $\n");
	/* Register driver for 3480/3490 tapes. */
	rc = ccw_driver_register(&tape_34xx_driver);
	if (rc)
		DBF_EVENT(3, "34xx init failed\n");
	else
		DBF_EVENT(3, "34xx registered\n");
	return rc;
}

static void
tape_34xx_exit(void)
{
	ccw_driver_unregister(&tape_34xx_driver);

	debug_unregister(TAPE_DBF_AREA);
}

MODULE_DEVICE_TABLE(ccw, tape_34xx_ids);
MODULE_AUTHOR("(C) 2001-2002 IBM Deutschland Entwicklung GmbH");
MODULE_DESCRIPTION("Linux on zSeries channel attached 3480 tape "
		   "device driver ($Revision: 1.23 $)");
MODULE_LICENSE("GPL");

module_init(tape_34xx_init);
module_exit(tape_34xx_exit);