[deliverable/linux.git] / drivers / scsi / libsrp.c

/*
 * SCSI RDAM Protocol lib functions
 *
 * Copyright (C) 2006 FUJITA Tomonori <tomof@acm.org>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */
#include <linux/err.h>
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_tgt.h>
#include <scsi/srp.h>
#include <scsi/libsrp.h>

enum srp_task_attributes {
	SRP_SIMPLE_TASK = 0,
	SRP_HEAD_TASK = 1,
	SRP_ORDERED_TASK = 2,
	SRP_ACA_TASK = 4
};

/* tmp - will replace with SCSI logging stuff */
#define eprintk(fmt, args...)					\
do {								\
	printk("%s(%d) " fmt, __func__, __LINE__, ##args);	\
} while (0)
/* #define dprintk eprintk */
#define dprintk(fmt, args...)

static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
			     struct srp_buf **ring)
{
	int i;
	struct iu_entry *iue;

	q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
	if (!q->pool)
		return -ENOMEM;
	q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
	if (!q->items)
		goto free_pool;

	spin_lock_init(&q->lock);
	kfifo_init(&q->queue, (void *) q->pool, max * sizeof(void *),
			      &q->lock);

	for (i = 0, iue = q->items; i < max; i++) {
		__kfifo_put(&q->queue, (void *) &iue, sizeof(void *));
		iue->sbuf = ring[i];
		iue++;
	}
	return 0;

	kfree(q->items);
free_pool:
	kfree(q->pool);
	return -ENOMEM;
}

static void srp_iu_pool_free(struct srp_queue *q)
{
	kfree(q->items);
	kfree(q->pool);
}

static struct srp_buf **srp_ring_alloc(struct device *dev,
				       size_t max, size_t size)
{
	int i;
	struct srp_buf **ring;

	ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
	if (!ring)
		return NULL;

	for (i = 0; i < max; i++) {
		ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL);
		if (!ring[i])
			goto out;
		ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
						  GFP_KERNEL);
		if (!ring[i]->buf)
			goto out;
	}
	return ring;

out:
	for (i = 0; i < max && ring[i]; i++) {
		if (ring[i]->buf)
			dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
		kfree(ring[i]);
	}
	kfree(ring);

	return NULL;
}

static void srp_ring_free(struct device *dev, struct srp_buf **ring, size_t max,
			  size_t size)
{
	int i;

	for (i = 0; i < max; i++) {
		dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
		kfree(ring[i]);
	}
	kfree(ring);
}

int srp_target_alloc(struct srp_target *target, struct device *dev,
		     size_t nr, size_t iu_size)
{
	int err;

	spin_lock_init(&target->lock);
	INIT_LIST_HEAD(&target->cmd_queue);

	target->dev = dev;
	dev_set_drvdata(target->dev, target);

	target->srp_iu_size = iu_size;
	target->rx_ring_size = nr;
	target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
	if (!target->rx_ring)
		return -ENOMEM;
	err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
	if (err)
		goto free_ring;

	return 0;

free_ring:
	srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
	return -ENOMEM;
}
EXPORT_SYMBOL_GPL(srp_target_alloc);

void srp_target_free(struct srp_target *target)
{
	srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
		      target->srp_iu_size);
	srp_iu_pool_free(&target->iu_queue);
}
EXPORT_SYMBOL_GPL(srp_target_free);

struct iu_entry *srp_iu_get(struct srp_target *target)
{
	struct iu_entry *iue = NULL;

	kfifo_get(&target->iu_queue.queue, (void *) &iue, sizeof(void *));
	if (!iue)
		return iue;
	iue->target = target;
	INIT_LIST_HEAD(&iue->ilist);
	iue->flags = 0;
	return iue;
}
EXPORT_SYMBOL_GPL(srp_iu_get);

void srp_iu_put(struct iu_entry *iue)
{
	kfifo_put(&iue->target->iu_queue.queue, (void *) &iue, sizeof(void *));
}
EXPORT_SYMBOL_GPL(srp_iu_put);

static int srp_direct_data(struct scsi_cmnd *sc, struct srp_direct_buf *md,
			   enum dma_data_direction dir, srp_rdma_t rdma_io,
			   int dma_map, int ext_desc)
{
	struct iu_entry *iue = NULL;
	struct scatterlist *sg = NULL;
	int err, nsg = 0, len;

	if (dma_map) {
		iue = (struct iu_entry *) sc->SCp.ptr;
		sg = scsi_sglist(sc);

		dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
			md->len, scsi_sg_count(sc));

		nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
				 DMA_BIDIRECTIONAL);
		if (!nsg) {
			printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
			return 0;
		}
		len = min(scsi_bufflen(sc), md->len);
	} else
		len = md->len;

	err = rdma_io(sc, sg, nsg, md, 1, dir, len);

	if (dma_map)
		dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);

	return err;
}

static int srp_indirect_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
			     struct srp_indirect_buf *id,
			     enum dma_data_direction dir, srp_rdma_t rdma_io,
			     int dma_map, int ext_desc)
{
	struct iu_entry *iue = NULL;
	struct srp_direct_buf *md = NULL;
	struct scatterlist dummy, *sg = NULL;
	dma_addr_t token = 0;
	int err = 0;
	int nmd, nsg = 0, len;

	if (dma_map || ext_desc) {
		iue = (struct iu_entry *) sc->SCp.ptr;
		sg = scsi_sglist(sc);

		dprintk("%p %u %u %d %d\n",
			iue, scsi_bufflen(sc), id->len,
			cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
	}

	nmd = id->table_desc.len / sizeof(struct srp_direct_buf);

	if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) ||
	    (dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
		md = &id->desc_list[0];
		goto rdma;
	}

	if (ext_desc && dma_map) {
		md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
				&token, GFP_KERNEL);
		if (!md) {
			eprintk("Can't get dma memory %u\n", id->table_desc.len);
			return -ENOMEM;
		}

		sg_init_one(&dummy, md, id->table_desc.len);
		sg_dma_address(&dummy) = token;
		sg_dma_len(&dummy) = id->table_desc.len;
		err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
			      id->table_desc.len);
		if (err) {
			eprintk("Error copying indirect table %d\n", err);
			goto free_mem;
		}
	} else {
		eprintk("This command uses external indirect buffer\n");
		return -EINVAL;
	}

rdma:
	if (dma_map) {
		nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
				 DMA_BIDIRECTIONAL);
		if (!nsg) {
			eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
			err = -EIO;
			goto free_mem;
		}
		len = min(scsi_bufflen(sc), id->len);
	} else
		len = id->len;

	err = rdma_io(sc, sg, nsg, md, nmd, dir, len);

	if (dma_map)
		dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);

free_mem:
	if (token && dma_map)
		dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);

	return err;
}

static int data_out_desc_size(struct srp_cmd *cmd)
{
	int size = 0;
	u8 fmt = cmd->buf_fmt >> 4;

	switch (fmt) {
	case SRP_NO_DATA_DESC:
		break;
	case SRP_DATA_DESC_DIRECT:
		size = sizeof(struct srp_direct_buf);
		break;
	case SRP_DATA_DESC_INDIRECT:
		size = sizeof(struct srp_indirect_buf) +
			sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
		break;
	default:
		eprintk("client error. Invalid data_out_format %x\n", fmt);
		break;
	}
	return size;
}

/*
 * TODO: this can be called multiple times for a single command if it
 * has very long data.
 */
int srp_transfer_data(struct scsi_cmnd *sc, struct srp_cmd *cmd,
		      srp_rdma_t rdma_io, int dma_map, int ext_desc)
{
	struct srp_direct_buf *md;
	struct srp_indirect_buf *id;
	enum dma_data_direction dir;
	int offset, err = 0;
	u8 format;

	offset = cmd->add_cdb_len * 4;

	dir = srp_cmd_direction(cmd);
	if (dir == DMA_FROM_DEVICE)
		offset += data_out_desc_size(cmd);

	if (dir == DMA_TO_DEVICE)
		format = cmd->buf_fmt >> 4;
	else
		format = cmd->buf_fmt & ((1U << 4) - 1);

	switch (format) {
	case SRP_NO_DATA_DESC:
		break;
	case SRP_DATA_DESC_DIRECT:
		md = (struct srp_direct_buf *)
			(cmd->add_data + offset);
		err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
		break;
	case SRP_DATA_DESC_INDIRECT:
		id = (struct srp_indirect_buf *)
			(cmd->add_data + offset);
		err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
					ext_desc);
		break;
	default:
		eprintk("Unknown format %d %x\n", dir, format);
		err = -EINVAL;
	}

	return err;
}
EXPORT_SYMBOL_GPL(srp_transfer_data);

static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
{
	struct srp_direct_buf *md;
	struct srp_indirect_buf *id;
	int len = 0, offset = cmd->add_cdb_len * 4;
	u8 fmt;

	if (dir == DMA_TO_DEVICE)
		fmt = cmd->buf_fmt >> 4;
	else {
		fmt = cmd->buf_fmt & ((1U << 4) - 1);
		offset += data_out_desc_size(cmd);
	}

	switch (fmt) {
	case SRP_NO_DATA_DESC:
		break;
	case SRP_DATA_DESC_DIRECT:
		md = (struct srp_direct_buf *) (cmd->add_data + offset);
		len = md->len;
		break;
	case SRP_DATA_DESC_INDIRECT:
		id = (struct srp_indirect_buf *) (cmd->add_data + offset);
		len = id->len;
		break;
	default:
		eprintk("invalid data format %x\n", fmt);
		break;
	}
	return len;
}

int srp_cmd_queue(struct Scsi_Host *shost, struct srp_cmd *cmd, void *info,
		  u64 itn_id, u64 addr)
{
	enum dma_data_direction dir;
	struct scsi_cmnd *sc;
	int tag, len, err;

	switch (cmd->task_attr) {
	case SRP_SIMPLE_TASK:
		tag = MSG_SIMPLE_TAG;
		break;
	case SRP_ORDERED_TASK:
		tag = MSG_ORDERED_TAG;
		break;
	case SRP_HEAD_TASK:
		tag = MSG_HEAD_TAG;
		break;
	default:
		eprintk("Task attribute %d not supported\n", cmd->task_attr);
		tag = MSG_ORDERED_TAG;
	}

	dir = srp_cmd_direction(cmd);
	len = vscsis_data_length(cmd, dir);

	dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
		cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);

	sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
	if (!sc)
		return -ENOMEM;

	sc->SCp.ptr = info;
	memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
	sc->sdb.length = len;
	sc->sdb.table.sgl = (void *) (unsigned long) addr;
	sc->tag = tag;
	err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
				     cmd->tag);
	if (err)
		scsi_host_put_command(shost, sc);

	return err;
}
EXPORT_SYMBOL_GPL(srp_cmd_queue);

MODULE_DESCRIPTION("SCSI RDAM Protocol lib functions");
MODULE_AUTHOR("FUJITA Tomonori");
MODULE_LICENSE("GPL");
Commit	Line	Data
26b14823 FT	1	/*
	2	* SCSI RDAM Protocol lib functions
	3	*
	4	* Copyright (C) 2006 FUJITA Tomonori <tomof@acm.org>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License as
	8	* published by the Free Software Foundation; either version 2 of the
	9	* License, or (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	19	* 02110-1301 USA
	20	*/
	21	#include <linux/err.h>
	22	#include <linux/kfifo.h>
	23	#include <linux/scatterlist.h>
	24	#include <linux/dma-mapping.h>
26b14823 FT	25	#include <scsi/scsi.h>
	26	#include <scsi/scsi_cmnd.h>
	27	#include <scsi/scsi_tcq.h>
	28	#include <scsi/scsi_tgt.h>
	29	#include <scsi/srp.h>
	30	#include <scsi/libsrp.h>
	31
	32	enum srp_task_attributes {
	33	SRP_SIMPLE_TASK = 0,
	34	SRP_HEAD_TASK = 1,
	35	SRP_ORDERED_TASK = 2,
	36	SRP_ACA_TASK = 4
	37	};
	38
	39	/* tmp - will replace with SCSI logging stuff */
	40	#define eprintk(fmt, args...) \
	41	do { \
cadbd4a5	42	printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
26b14823 FT	43	} while (0)
	44	/* #define dprintk eprintk */
	45	#define dprintk(fmt, args...)
	46
	47	static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
	48	struct srp_buf **ring)
	49	{
	50	int i;
	51	struct iu_entry *iue;
	52
	53	q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
	54	if (!q->pool)
	55	return -ENOMEM;
	56	q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
	57	if (!q->items)
	58	goto free_pool;
	59
	60	spin_lock_init(&q->lock);
45465487 SS	61	kfifo_init(&q->queue, (void ) q->pool, max sizeof(void *),
45465487 SS	62	&q->lock);
26b14823 FT	63
26b14823 FT	64	for (i = 0, iue = q->items; i < max; i++) {
45465487	65	__kfifo_put(&q->queue, (void ) &iue, sizeof(void ));
26b14823 FT	66	iue->sbuf = ring[i];
	67	iue++;
	68	}
	69	return 0;
	70
26b14823 FT	71	kfree(q->items);
	72	free_pool:
	73	kfree(q->pool);
	74	return -ENOMEM;
	75	}
	76
	77	static void srp_iu_pool_free(struct srp_queue *q)
	78	{
	79	kfree(q->items);
	80	kfree(q->pool);
	81	}
	82
	83	static struct srp_buf *srp_ring_alloc(struct device dev,
	84	size_t max, size_t size)
	85	{
	86	int i;
	87	struct srp_buf **ring;
	88
	89	ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
	90	if (!ring)
	91	return NULL;
	92
	93	for (i = 0; i < max; i++) {
	94	ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL);
	95	if (!ring[i])
	96	goto out;
	97	ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
	98	GFP_KERNEL);
	99	if (!ring[i]->buf)
	100	goto out;
	101	}
	102	return ring;
	103
	104	out:
	105	for (i = 0; i < max && ring[i]; i++) {
	106	if (ring[i]->buf)
	107	dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
	108	kfree(ring[i]);
	109	}
	110	kfree(ring);
	111
	112	return NULL;
	113	}
	114
	115	static void srp_ring_free(struct device dev, struct srp_buf *ring, size_t max,
	116	size_t size)
	117	{
	118	int i;
	119
	120	for (i = 0; i < max; i++) {
	121	dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
	122	kfree(ring[i]);
	123	}
afffd3da	124	kfree(ring);
26b14823 FT	125	}
	126
	127	int srp_target_alloc(struct srp_target target, struct device dev,
	128	size_t nr, size_t iu_size)
	129	{
	130	int err;
	131
	132	spin_lock_init(&target->lock);
	133	INIT_LIST_HEAD(&target->cmd_queue);
	134
	135	target->dev = dev;
78c55d76	136	dev_set_drvdata(target->dev, target);
26b14823 FT	137
	138	target->srp_iu_size = iu_size;
	139	target->rx_ring_size = nr;
	140	target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
	141	if (!target->rx_ring)
	142	return -ENOMEM;
	143	err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
	144	if (err)
	145	goto free_ring;
	146
	147	return 0;
	148
	149	free_ring:
	150	srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
	151	return -ENOMEM;
	152	}
	153	EXPORT_SYMBOL_GPL(srp_target_alloc);
	154
	155	void srp_target_free(struct srp_target *target)
	156	{
	157	srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
	158	target->srp_iu_size);
	159	srp_iu_pool_free(&target->iu_queue);
	160	}
	161	EXPORT_SYMBOL_GPL(srp_target_free);
	162
	163	struct iu_entry srp_iu_get(struct srp_target target)
	164	{
	165	struct iu_entry *iue = NULL;
	166
45465487	167	kfifo_get(&target->iu_queue.queue, (void ) &iue, sizeof(void ));
26b14823 FT	168	if (!iue)
	169	return iue;
	170	iue->target = target;
	171	INIT_LIST_HEAD(&iue->ilist);
	172	iue->flags = 0;
	173	return iue;
	174	}
	175	EXPORT_SYMBOL_GPL(srp_iu_get);
	176
	177	void srp_iu_put(struct iu_entry *iue)
	178	{
45465487	179	kfifo_put(&iue->target->iu_queue.queue, (void ) &iue, sizeof(void ));
26b14823 FT	180	}
	181	EXPORT_SYMBOL_GPL(srp_iu_put);
	182
	183	static int srp_direct_data(struct scsi_cmnd sc, struct srp_direct_buf md,
	184	enum dma_data_direction dir, srp_rdma_t rdma_io,
	185	int dma_map, int ext_desc)
	186	{
	187	struct iu_entry *iue = NULL;
	188	struct scatterlist *sg = NULL;
	189	int err, nsg = 0, len;
	190
	191	if (dma_map) {
	192	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	193	sg = scsi_sglist(sc);
26b14823	194
f10ab66f FT	195	dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
f10ab66f FT	196	md->len, scsi_sg_count(sc));
26b14823	197
f10ab66f	198	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
26b14823 FT	199	DMA_BIDIRECTIONAL);
26b14823 FT	200	if (!nsg) {
f10ab66f	201	printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
26b14823 FT	202	return 0;
26b14823 FT	203	}
f10ab66f	204	len = min(scsi_bufflen(sc), md->len);
26b14823 FT	205	} else
	206	len = md->len;
	207
	208	err = rdma_io(sc, sg, nsg, md, 1, dir, len);
	209
	210	if (dma_map)
	211	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	212
	213	return err;
	214	}
	215
	216	static int srp_indirect_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	217	struct srp_indirect_buf *id,
	218	enum dma_data_direction dir, srp_rdma_t rdma_io,
	219	int dma_map, int ext_desc)
	220	{
	221	struct iu_entry *iue = NULL;
	222	struct srp_direct_buf *md = NULL;
	223	struct scatterlist dummy, *sg = NULL;
	224	dma_addr_t token = 0;
ad1331a7	225	int err = 0;
26b14823 FT	226	int nmd, nsg = 0, len;
	227
	228	if (dma_map \|\| ext_desc) {
	229	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	230	sg = scsi_sglist(sc);
26b14823 FT	231
26b14823 FT	232	dprintk("%p %u %u %d %d\n",
f10ab66f	233	iue, scsi_bufflen(sc), id->len,
26b14823 FT	234	cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
	235	}
	236
	237	nmd = id->table_desc.len / sizeof(struct srp_direct_buf);
	238
	239	if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) \|\|
	240	(dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
	241	md = &id->desc_list[0];
	242	goto rdma;
	243	}
	244
	245	if (ext_desc && dma_map) {
	246	md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
	247	&token, GFP_KERNEL);
	248	if (!md) {
	249	eprintk("Can't get dma memory %u\n", id->table_desc.len);
	250	return -ENOMEM;
	251	}
	252
	253	sg_init_one(&dummy, md, id->table_desc.len);
	254	sg_dma_address(&dummy) = token;
bcd4e225	255	sg_dma_len(&dummy) = id->table_desc.len;
26b14823 FT	256	err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
26b14823 FT	257	id->table_desc.len);
ad1331a7 BB	258	if (err) {
ad1331a7 BB	259	eprintk("Error copying indirect table %d\n", err);
26b14823 FT	260	goto free_mem;
	261	}
	262	} else {
	263	eprintk("This command uses external indirect buffer\n");
	264	return -EINVAL;
	265	}
	266
	267	rdma:
	268	if (dma_map) {
f10ab66f FT	269	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
f10ab66f FT	270	DMA_BIDIRECTIONAL);
26b14823	271	if (!nsg) {
f10ab66f	272	eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
ad1331a7	273	err = -EIO;
26b14823 FT	274	goto free_mem;
26b14823 FT	275	}
f10ab66f	276	len = min(scsi_bufflen(sc), id->len);
26b14823 FT	277	} else
	278	len = id->len;
	279
	280	err = rdma_io(sc, sg, nsg, md, nmd, dir, len);
	281
	282	if (dma_map)
	283	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	284
	285	free_mem:
	286	if (token && dma_map)
	287	dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
	288
ad1331a7	289	return err;
26b14823 FT	290	}
	291
	292	static int data_out_desc_size(struct srp_cmd *cmd)
	293	{
	294	int size = 0;
	295	u8 fmt = cmd->buf_fmt >> 4;
	296
	297	switch (fmt) {
	298	case SRP_NO_DATA_DESC:
	299	break;
	300	case SRP_DATA_DESC_DIRECT:
	301	size = sizeof(struct srp_direct_buf);
	302	break;
	303	case SRP_DATA_DESC_INDIRECT:
	304	size = sizeof(struct srp_indirect_buf) +
	305	sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
	306	break;
	307	default:
	308	eprintk("client error. Invalid data_out_format %x\n", fmt);
	309	break;
	310	}
	311	return size;
	312	}
	313
	314	/*
	315	* TODO: this can be called multiple times for a single command if it
	316	* has very long data.
	317	*/
	318	int srp_transfer_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	319	srp_rdma_t rdma_io, int dma_map, int ext_desc)
	320	{
	321	struct srp_direct_buf *md;
	322	struct srp_indirect_buf *id;
	323	enum dma_data_direction dir;
	324	int offset, err = 0;
	325	u8 format;
	326
	327	offset = cmd->add_cdb_len * 4;
	328
	329	dir = srp_cmd_direction(cmd);
	330	if (dir == DMA_FROM_DEVICE)
	331	offset += data_out_desc_size(cmd);
	332
	333	if (dir == DMA_TO_DEVICE)
	334	format = cmd->buf_fmt >> 4;
	335	else
	336	format = cmd->buf_fmt & ((1U << 4) - 1);
	337
	338	switch (format) {
	339	case SRP_NO_DATA_DESC:
	340	break;
	341	case SRP_DATA_DESC_DIRECT:
	342	md = (struct srp_direct_buf *)
	343	(cmd->add_data + offset);
	344	err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
	345	break;
	346	case SRP_DATA_DESC_INDIRECT:
	347	id = (struct srp_indirect_buf *)
	348	(cmd->add_data + offset);
	349	err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
	350	ext_desc);
	351	break;
	352	default:
	353	eprintk("Unknown format %d %x\n", dir, format);
ad1331a7	354	err = -EINVAL;
26b14823 FT	355	}
	356
	357	return err;
	358	}
	359	EXPORT_SYMBOL_GPL(srp_transfer_data);
	360
	361	static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
	362	{
	363	struct srp_direct_buf *md;
	364	struct srp_indirect_buf *id;
	365	int len = 0, offset = cmd->add_cdb_len * 4;
	366	u8 fmt;
	367
	368	if (dir == DMA_TO_DEVICE)
	369	fmt = cmd->buf_fmt >> 4;
	370	else {
	371	fmt = cmd->buf_fmt & ((1U << 4) - 1);
	372	offset += data_out_desc_size(cmd);
	373	}
	374
	375	switch (fmt) {
	376	case SRP_NO_DATA_DESC:
	377	break;
	378	case SRP_DATA_DESC_DIRECT:
	379	md = (struct srp_direct_buf *) (cmd->add_data + offset);
	380	len = md->len;
	381	break;
	382	case SRP_DATA_DESC_INDIRECT:
	383	id = (struct srp_indirect_buf *) (cmd->add_data + offset);
	384	len = id->len;
	385	break;
	386	default:
	387	eprintk("invalid data format %x\n", fmt);
	388	break;
	389	}
	390	return len;
	391	}
	392
	393	int srp_cmd_queue(struct Scsi_Host shost, struct srp_cmd cmd, void *info,
17b0bcfa	394	u64 itn_id, u64 addr)
26b14823 FT	395	{
	396	enum dma_data_direction dir;
	397	struct scsi_cmnd *sc;
	398	int tag, len, err;
	399
	400	switch (cmd->task_attr) {
	401	case SRP_SIMPLE_TASK:
	402	tag = MSG_SIMPLE_TAG;
	403	break;
	404	case SRP_ORDERED_TASK:
	405	tag = MSG_ORDERED_TAG;
	406	break;
	407	case SRP_HEAD_TASK:
	408	tag = MSG_HEAD_TAG;
	409	break;
	410	default:
	411	eprintk("Task attribute %d not supported\n", cmd->task_attr);
	412	tag = MSG_ORDERED_TAG;
	413	}
	414
	415	dir = srp_cmd_direction(cmd);
	416	len = vscsis_data_length(cmd, dir);
	417
	418	dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
	419	cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);
	420
	421	sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
	422	if (!sc)
	423	return -ENOMEM;
	424
	425	sc->SCp.ptr = info;
	426	memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
30b0c37b BH	427	sc->sdb.length = len;
30b0c37b BH	428	sc->sdb.table.sgl = (void *) (unsigned long) addr;
26b14823	429	sc->tag = tag;
17b0bcfa FT	430	err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
17b0bcfa FT	431	cmd->tag);
26b14823 FT	432	if (err)
	433	scsi_host_put_command(shost, sc);
	434
	435	return err;
	436	}
	437	EXPORT_SYMBOL_GPL(srp_cmd_queue);
	438
	439	MODULE_DESCRIPTION("SCSI RDAM Protocol lib functions");
	440	MODULE_AUTHOR("FUJITA Tomonori");
	441	MODULE_LICENSE("GPL");