[linux-2.6-block.git] / drivers / scsi / libsrp.c

/*
 * SCSI RDMA 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/slab.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 *));

	for (i = 0, iue = q->items; i < max; i++) {
		kfifo_in(&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;

	if (kfifo_out_locked(&target->iu_queue.queue, (void *) &iue,
		sizeof(void *), &target->iu_queue.lock) != sizeof(void *)) {
			WARN_ONCE(1, "unexpected fifo state");
			return NULL;
	}
	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_in_locked(&iue->target->iu_queue.queue, (void *) &iue,
			sizeof(void *), &iue->target->iu_queue.lock);
}
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 & ~3;

	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 & ~3;
	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 RDMA Protocol lib functions");
MODULE_AUTHOR("FUJITA Tomonori");
MODULE_LICENSE("GPL");
Commit	Line	Data
26b14823	1	/*
40c4f3e4	2	* SCSI RDMA Protocol lib functions
26b14823 FT	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>
5a0e3ad6	22	#include <linux/slab.h>
26b14823 FT	23	#include <linux/kfifo.h>
	24	#include <linux/scatterlist.h>
	25	#include <linux/dma-mapping.h>
26b14823 FT	26	#include <scsi/scsi.h>
	27	#include <scsi/scsi_cmnd.h>
	28	#include <scsi/scsi_tcq.h>
	29	#include <scsi/scsi_tgt.h>
	30	#include <scsi/srp.h>
	31	#include <scsi/libsrp.h>
	32
	33	enum srp_task_attributes {
	34	SRP_SIMPLE_TASK = 0,
	35	SRP_HEAD_TASK = 1,
	36	SRP_ORDERED_TASK = 2,
	37	SRP_ACA_TASK = 4
	38	};
	39
	40	/* tmp - will replace with SCSI logging stuff */
	41	#define eprintk(fmt, args...) \
	42	do { \
cadbd4a5	43	printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
26b14823 FT	44	} while (0)
	45	/* #define dprintk eprintk */
	46	#define dprintk(fmt, args...)
	47
	48	static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
	49	struct srp_buf **ring)
	50	{
	51	int i;
	52	struct iu_entry *iue;
	53
	54	q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
	55	if (!q->pool)
	56	return -ENOMEM;
	57	q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
	58	if (!q->items)
	59	goto free_pool;
	60
	61	spin_lock_init(&q->lock);
c1e13f25	62	kfifo_init(&q->queue, (void ) q->pool, max sizeof(void *));
26b14823 FT	63
26b14823 FT	64	for (i = 0, iue = q->items; i < max; i++) {
7acd72eb	65	kfifo_in(&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
9842c38e SS	167	if (kfifo_out_locked(&target->iu_queue.queue, (void *) &iue,
	168	sizeof(void ), &target->iu_queue.lock) != sizeof(void )) {
	169	WARN_ONCE(1, "unexpected fifo state");
	170	return NULL;
	171	}
26b14823 FT	172	if (!iue)
	173	return iue;
	174	iue->target = target;
	175	INIT_LIST_HEAD(&iue->ilist);
	176	iue->flags = 0;
	177	return iue;
	178	}
	179	EXPORT_SYMBOL_GPL(srp_iu_get);
	180
	181	void srp_iu_put(struct iu_entry *iue)
	182	{
7acd72eb	183	kfifo_in_locked(&iue->target->iu_queue.queue, (void *) &iue,
c1e13f25	184	sizeof(void *), &iue->target->iu_queue.lock);
26b14823 FT	185	}
	186	EXPORT_SYMBOL_GPL(srp_iu_put);
	187
	188	static int srp_direct_data(struct scsi_cmnd sc, struct srp_direct_buf md,
	189	enum dma_data_direction dir, srp_rdma_t rdma_io,
	190	int dma_map, int ext_desc)
	191	{
	192	struct iu_entry *iue = NULL;
	193	struct scatterlist *sg = NULL;
	194	int err, nsg = 0, len;
	195
	196	if (dma_map) {
	197	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	198	sg = scsi_sglist(sc);
26b14823	199
f10ab66f FT	200	dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
f10ab66f FT	201	md->len, scsi_sg_count(sc));
26b14823	202
f10ab66f	203	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
26b14823 FT	204	DMA_BIDIRECTIONAL);
26b14823 FT	205	if (!nsg) {
f10ab66f	206	printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
26b14823 FT	207	return 0;
26b14823 FT	208	}
f10ab66f	209	len = min(scsi_bufflen(sc), md->len);
26b14823 FT	210	} else
	211	len = md->len;
	212
	213	err = rdma_io(sc, sg, nsg, md, 1, dir, len);
	214
	215	if (dma_map)
	216	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	217
	218	return err;
	219	}
	220
	221	static int srp_indirect_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	222	struct srp_indirect_buf *id,
	223	enum dma_data_direction dir, srp_rdma_t rdma_io,
	224	int dma_map, int ext_desc)
	225	{
	226	struct iu_entry *iue = NULL;
	227	struct srp_direct_buf *md = NULL;
	228	struct scatterlist dummy, *sg = NULL;
	229	dma_addr_t token = 0;
ad1331a7	230	int err = 0;
26b14823 FT	231	int nmd, nsg = 0, len;
	232
	233	if (dma_map \|\| ext_desc) {
	234	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	235	sg = scsi_sglist(sc);
26b14823 FT	236
26b14823 FT	237	dprintk("%p %u %u %d %d\n",
f10ab66f	238	iue, scsi_bufflen(sc), id->len,
26b14823 FT	239	cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
	240	}
	241
	242	nmd = id->table_desc.len / sizeof(struct srp_direct_buf);
	243
	244	if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) \|\|
	245	(dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
	246	md = &id->desc_list[0];
	247	goto rdma;
	248	}
	249
	250	if (ext_desc && dma_map) {
	251	md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
	252	&token, GFP_KERNEL);
	253	if (!md) {
	254	eprintk("Can't get dma memory %u\n", id->table_desc.len);
	255	return -ENOMEM;
	256	}
	257
	258	sg_init_one(&dummy, md, id->table_desc.len);
	259	sg_dma_address(&dummy) = token;
bcd4e225	260	sg_dma_len(&dummy) = id->table_desc.len;
26b14823 FT	261	err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
26b14823 FT	262	id->table_desc.len);
ad1331a7 BB	263	if (err) {
ad1331a7 BB	264	eprintk("Error copying indirect table %d\n", err);
26b14823 FT	265	goto free_mem;
	266	}
	267	} else {
	268	eprintk("This command uses external indirect buffer\n");
	269	return -EINVAL;
	270	}
	271
	272	rdma:
	273	if (dma_map) {
f10ab66f FT	274	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
f10ab66f FT	275	DMA_BIDIRECTIONAL);
26b14823	276	if (!nsg) {
f10ab66f	277	eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
ad1331a7	278	err = -EIO;
26b14823 FT	279	goto free_mem;
26b14823 FT	280	}
f10ab66f	281	len = min(scsi_bufflen(sc), id->len);
26b14823 FT	282	} else
	283	len = id->len;
	284
	285	err = rdma_io(sc, sg, nsg, md, nmd, dir, len);
	286
	287	if (dma_map)
	288	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	289
	290	free_mem:
	291	if (token && dma_map)
	292	dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
	293
ad1331a7	294	return err;
26b14823 FT	295	}
	296
	297	static int data_out_desc_size(struct srp_cmd *cmd)
	298	{
	299	int size = 0;
	300	u8 fmt = cmd->buf_fmt >> 4;
	301
	302	switch (fmt) {
	303	case SRP_NO_DATA_DESC:
	304	break;
	305	case SRP_DATA_DESC_DIRECT:
	306	size = sizeof(struct srp_direct_buf);
	307	break;
	308	case SRP_DATA_DESC_INDIRECT:
	309	size = sizeof(struct srp_indirect_buf) +
	310	sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
	311	break;
	312	default:
	313	eprintk("client error. Invalid data_out_format %x\n", fmt);
	314	break;
	315	}
	316	return size;
	317	}
	318
	319	/*
	320	* TODO: this can be called multiple times for a single command if it
	321	* has very long data.
	322	*/
	323	int srp_transfer_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	324	srp_rdma_t rdma_io, int dma_map, int ext_desc)
	325	{
	326	struct srp_direct_buf *md;
	327	struct srp_indirect_buf *id;
	328	enum dma_data_direction dir;
	329	int offset, err = 0;
	330	u8 format;
	331
78d85019	332	offset = cmd->add_cdb_len & ~3;
26b14823 FT	333
	334	dir = srp_cmd_direction(cmd);
	335	if (dir == DMA_FROM_DEVICE)
	336	offset += data_out_desc_size(cmd);
	337
	338	if (dir == DMA_TO_DEVICE)
	339	format = cmd->buf_fmt >> 4;
	340	else
	341	format = cmd->buf_fmt & ((1U << 4) - 1);
	342
	343	switch (format) {
	344	case SRP_NO_DATA_DESC:
	345	break;
	346	case SRP_DATA_DESC_DIRECT:
	347	md = (struct srp_direct_buf *)
	348	(cmd->add_data + offset);
	349	err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
	350	break;
	351	case SRP_DATA_DESC_INDIRECT:
	352	id = (struct srp_indirect_buf *)
	353	(cmd->add_data + offset);
	354	err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
	355	ext_desc);
	356	break;
	357	default:
	358	eprintk("Unknown format %d %x\n", dir, format);
ad1331a7	359	err = -EINVAL;
26b14823 FT	360	}
	361
	362	return err;
	363	}
	364	EXPORT_SYMBOL_GPL(srp_transfer_data);
	365
	366	static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
	367	{
	368	struct srp_direct_buf *md;
	369	struct srp_indirect_buf *id;
78d85019	370	int len = 0, offset = cmd->add_cdb_len & ~3;
26b14823 FT	371	u8 fmt;
	372
	373	if (dir == DMA_TO_DEVICE)
	374	fmt = cmd->buf_fmt >> 4;
	375	else {
	376	fmt = cmd->buf_fmt & ((1U << 4) - 1);
	377	offset += data_out_desc_size(cmd);
	378	}
	379
	380	switch (fmt) {
	381	case SRP_NO_DATA_DESC:
	382	break;
	383	case SRP_DATA_DESC_DIRECT:
	384	md = (struct srp_direct_buf *) (cmd->add_data + offset);
	385	len = md->len;
	386	break;
	387	case SRP_DATA_DESC_INDIRECT:
	388	id = (struct srp_indirect_buf *) (cmd->add_data + offset);
	389	len = id->len;
	390	break;
	391	default:
	392	eprintk("invalid data format %x\n", fmt);
	393	break;
	394	}
	395	return len;
	396	}
	397
	398	int srp_cmd_queue(struct Scsi_Host shost, struct srp_cmd cmd, void *info,
17b0bcfa	399	u64 itn_id, u64 addr)
26b14823 FT	400	{
	401	enum dma_data_direction dir;
	402	struct scsi_cmnd *sc;
	403	int tag, len, err;
	404
	405	switch (cmd->task_attr) {
	406	case SRP_SIMPLE_TASK:
	407	tag = MSG_SIMPLE_TAG;
	408	break;
	409	case SRP_ORDERED_TASK:
	410	tag = MSG_ORDERED_TAG;
	411	break;
	412	case SRP_HEAD_TASK:
	413	tag = MSG_HEAD_TAG;
	414	break;
	415	default:
	416	eprintk("Task attribute %d not supported\n", cmd->task_attr);
	417	tag = MSG_ORDERED_TAG;
	418	}
	419
	420	dir = srp_cmd_direction(cmd);
	421	len = vscsis_data_length(cmd, dir);
	422
	423	dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
	424	cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);
	425
	426	sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
	427	if (!sc)
	428	return -ENOMEM;
	429
	430	sc->SCp.ptr = info;
	431	memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
30b0c37b BH	432	sc->sdb.length = len;
30b0c37b BH	433	sc->sdb.table.sgl = (void *) (unsigned long) addr;
26b14823	434	sc->tag = tag;
17b0bcfa FT	435	err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
17b0bcfa FT	436	cmd->tag);
26b14823 FT	437	if (err)
	438	scsi_host_put_command(shost, sc);
	439
	440	return err;
	441	}
	442	EXPORT_SYMBOL_GPL(srp_cmd_queue);
	443
40c4f3e4	444	MODULE_DESCRIPTION("SCSI RDMA Protocol lib functions");
26b14823 FT	445	MODULE_AUTHOR("FUJITA Tomonori");
26b14823 FT	446	MODULE_LICENSE("GPL");