[GitHub/mt8127/android_kernel_alcatel_ttab.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 <linux/module.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>
acf3368f	26	#include <linux/module.h>
26b14823 FT	27	#include <scsi/scsi.h>
	28	#include <scsi/scsi_cmnd.h>
	29	#include <scsi/scsi_tcq.h>
	30	#include <scsi/scsi_tgt.h>
	31	#include <scsi/srp.h>
	32	#include <scsi/libsrp.h>
	33
	34	enum srp_task_attributes {
	35	SRP_SIMPLE_TASK = 0,
	36	SRP_HEAD_TASK = 1,
	37	SRP_ORDERED_TASK = 2,
	38	SRP_ACA_TASK = 4
	39	};
	40
	41	/* tmp - will replace with SCSI logging stuff */
	42	#define eprintk(fmt, args...) \
	43	do { \
cadbd4a5	44	printk("%s(%d) " fmt, __func__, __LINE__, ##args); \
26b14823 FT	45	} while (0)
	46	/* #define dprintk eprintk */
	47	#define dprintk(fmt, args...)
	48
	49	static int srp_iu_pool_alloc(struct srp_queue *q, size_t max,
	50	struct srp_buf **ring)
	51	{
	52	int i;
	53	struct iu_entry *iue;
	54
	55	q->pool = kcalloc(max, sizeof(struct iu_entry *), GFP_KERNEL);
	56	if (!q->pool)
	57	return -ENOMEM;
	58	q->items = kcalloc(max, sizeof(struct iu_entry), GFP_KERNEL);
	59	if (!q->items)
	60	goto free_pool;
	61
	62	spin_lock_init(&q->lock);
c1e13f25	63	kfifo_init(&q->queue, (void ) q->pool, max sizeof(void *));
26b14823 FT	64
26b14823 FT	65	for (i = 0, iue = q->items; i < max; i++) {
7acd72eb	66	kfifo_in(&q->queue, (void ) &iue, sizeof(void ));
26b14823 FT	67	iue->sbuf = ring[i];
	68	iue++;
	69	}
	70	return 0;
	71
26b14823 FT	72	kfree(q->items);
	73	free_pool:
	74	kfree(q->pool);
	75	return -ENOMEM;
	76	}
	77
	78	static void srp_iu_pool_free(struct srp_queue *q)
	79	{
	80	kfree(q->items);
	81	kfree(q->pool);
	82	}
	83
	84	static struct srp_buf *srp_ring_alloc(struct device dev,
	85	size_t max, size_t size)
	86	{
	87	int i;
	88	struct srp_buf **ring;
	89
	90	ring = kcalloc(max, sizeof(struct srp_buf *), GFP_KERNEL);
	91	if (!ring)
	92	return NULL;
	93
	94	for (i = 0; i < max; i++) {
	95	ring[i] = kzalloc(sizeof(struct srp_buf), GFP_KERNEL);
	96	if (!ring[i])
	97	goto out;
	98	ring[i]->buf = dma_alloc_coherent(dev, size, &ring[i]->dma,
	99	GFP_KERNEL);
	100	if (!ring[i]->buf)
	101	goto out;
	102	}
	103	return ring;
	104
	105	out:
	106	for (i = 0; i < max && ring[i]; i++) {
	107	if (ring[i]->buf)
	108	dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
	109	kfree(ring[i]);
	110	}
	111	kfree(ring);
	112
	113	return NULL;
	114	}
	115
	116	static void srp_ring_free(struct device dev, struct srp_buf *ring, size_t max,
	117	size_t size)
	118	{
	119	int i;
	120
	121	for (i = 0; i < max; i++) {
	122	dma_free_coherent(dev, size, ring[i]->buf, ring[i]->dma);
	123	kfree(ring[i]);
	124	}
afffd3da	125	kfree(ring);
26b14823 FT	126	}
	127
	128	int srp_target_alloc(struct srp_target target, struct device dev,
	129	size_t nr, size_t iu_size)
	130	{
	131	int err;
	132
	133	spin_lock_init(&target->lock);
	134	INIT_LIST_HEAD(&target->cmd_queue);
	135
	136	target->dev = dev;
78c55d76	137	dev_set_drvdata(target->dev, target);
26b14823 FT	138
	139	target->srp_iu_size = iu_size;
	140	target->rx_ring_size = nr;
	141	target->rx_ring = srp_ring_alloc(target->dev, nr, iu_size);
	142	if (!target->rx_ring)
	143	return -ENOMEM;
	144	err = srp_iu_pool_alloc(&target->iu_queue, nr, target->rx_ring);
	145	if (err)
	146	goto free_ring;
	147
	148	return 0;
	149
	150	free_ring:
	151	srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
	152	return -ENOMEM;
	153	}
	154	EXPORT_SYMBOL_GPL(srp_target_alloc);
	155
	156	void srp_target_free(struct srp_target *target)
	157	{
	158	srp_ring_free(target->dev, target->rx_ring, target->rx_ring_size,
	159	target->srp_iu_size);
	160	srp_iu_pool_free(&target->iu_queue);
	161	}
	162	EXPORT_SYMBOL_GPL(srp_target_free);
	163
	164	struct iu_entry srp_iu_get(struct srp_target target)
	165	{
	166	struct iu_entry *iue = NULL;
	167
9842c38e SS	168	if (kfifo_out_locked(&target->iu_queue.queue, (void *) &iue,
	169	sizeof(void ), &target->iu_queue.lock) != sizeof(void )) {
	170	WARN_ONCE(1, "unexpected fifo state");
	171	return NULL;
	172	}
26b14823 FT	173	if (!iue)
	174	return iue;
	175	iue->target = target;
	176	INIT_LIST_HEAD(&iue->ilist);
	177	iue->flags = 0;
	178	return iue;
	179	}
	180	EXPORT_SYMBOL_GPL(srp_iu_get);
	181
	182	void srp_iu_put(struct iu_entry *iue)
	183	{
7acd72eb	184	kfifo_in_locked(&iue->target->iu_queue.queue, (void *) &iue,
c1e13f25	185	sizeof(void *), &iue->target->iu_queue.lock);
26b14823 FT	186	}
	187	EXPORT_SYMBOL_GPL(srp_iu_put);
	188
	189	static int srp_direct_data(struct scsi_cmnd sc, struct srp_direct_buf md,
	190	enum dma_data_direction dir, srp_rdma_t rdma_io,
	191	int dma_map, int ext_desc)
	192	{
	193	struct iu_entry *iue = NULL;
	194	struct scatterlist *sg = NULL;
	195	int err, nsg = 0, len;
	196
	197	if (dma_map) {
	198	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	199	sg = scsi_sglist(sc);
26b14823	200
f10ab66f FT	201	dprintk("%p %u %u %d\n", iue, scsi_bufflen(sc),
f10ab66f FT	202	md->len, scsi_sg_count(sc));
26b14823	203
f10ab66f	204	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
26b14823 FT	205	DMA_BIDIRECTIONAL);
26b14823 FT	206	if (!nsg) {
f10ab66f	207	printk("fail to map %p %d\n", iue, scsi_sg_count(sc));
26b14823 FT	208	return 0;
26b14823 FT	209	}
f10ab66f	210	len = min(scsi_bufflen(sc), md->len);
26b14823 FT	211	} else
	212	len = md->len;
	213
	214	err = rdma_io(sc, sg, nsg, md, 1, dir, len);
	215
	216	if (dma_map)
	217	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	218
	219	return err;
	220	}
	221
	222	static int srp_indirect_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	223	struct srp_indirect_buf *id,
	224	enum dma_data_direction dir, srp_rdma_t rdma_io,
	225	int dma_map, int ext_desc)
	226	{
	227	struct iu_entry *iue = NULL;
	228	struct srp_direct_buf *md = NULL;
	229	struct scatterlist dummy, *sg = NULL;
	230	dma_addr_t token = 0;
ad1331a7	231	int err = 0;
26b14823 FT	232	int nmd, nsg = 0, len;
	233
	234	if (dma_map \|\| ext_desc) {
	235	iue = (struct iu_entry *) sc->SCp.ptr;
f10ab66f	236	sg = scsi_sglist(sc);
26b14823 FT	237
26b14823 FT	238	dprintk("%p %u %u %d %d\n",
f10ab66f	239	iue, scsi_bufflen(sc), id->len,
26b14823 FT	240	cmd->data_in_desc_cnt, cmd->data_out_desc_cnt);
	241	}
	242
	243	nmd = id->table_desc.len / sizeof(struct srp_direct_buf);
	244
	245	if ((dir == DMA_FROM_DEVICE && nmd == cmd->data_in_desc_cnt) \|\|
	246	(dir == DMA_TO_DEVICE && nmd == cmd->data_out_desc_cnt)) {
	247	md = &id->desc_list[0];
	248	goto rdma;
	249	}
	250
	251	if (ext_desc && dma_map) {
	252	md = dma_alloc_coherent(iue->target->dev, id->table_desc.len,
	253	&token, GFP_KERNEL);
	254	if (!md) {
	255	eprintk("Can't get dma memory %u\n", id->table_desc.len);
	256	return -ENOMEM;
	257	}
	258
	259	sg_init_one(&dummy, md, id->table_desc.len);
	260	sg_dma_address(&dummy) = token;
bcd4e225	261	sg_dma_len(&dummy) = id->table_desc.len;
26b14823 FT	262	err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
26b14823 FT	263	id->table_desc.len);
ad1331a7 BB	264	if (err) {
ad1331a7 BB	265	eprintk("Error copying indirect table %d\n", err);
26b14823 FT	266	goto free_mem;
	267	}
	268	} else {
	269	eprintk("This command uses external indirect buffer\n");
	270	return -EINVAL;
	271	}
	272
	273	rdma:
	274	if (dma_map) {
f10ab66f FT	275	nsg = dma_map_sg(iue->target->dev, sg, scsi_sg_count(sc),
f10ab66f FT	276	DMA_BIDIRECTIONAL);
26b14823	277	if (!nsg) {
f10ab66f	278	eprintk("fail to map %p %d\n", iue, scsi_sg_count(sc));
ad1331a7	279	err = -EIO;
26b14823 FT	280	goto free_mem;
26b14823 FT	281	}
f10ab66f	282	len = min(scsi_bufflen(sc), id->len);
26b14823 FT	283	} else
	284	len = id->len;
	285
	286	err = rdma_io(sc, sg, nsg, md, nmd, dir, len);
	287
	288	if (dma_map)
	289	dma_unmap_sg(iue->target->dev, sg, nsg, DMA_BIDIRECTIONAL);
	290
	291	free_mem:
	292	if (token && dma_map)
	293	dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
	294
ad1331a7	295	return err;
26b14823 FT	296	}
	297
	298	static int data_out_desc_size(struct srp_cmd *cmd)
	299	{
	300	int size = 0;
	301	u8 fmt = cmd->buf_fmt >> 4;
	302
	303	switch (fmt) {
	304	case SRP_NO_DATA_DESC:
	305	break;
	306	case SRP_DATA_DESC_DIRECT:
	307	size = sizeof(struct srp_direct_buf);
	308	break;
	309	case SRP_DATA_DESC_INDIRECT:
	310	size = sizeof(struct srp_indirect_buf) +
	311	sizeof(struct srp_direct_buf) * cmd->data_out_desc_cnt;
	312	break;
	313	default:
	314	eprintk("client error. Invalid data_out_format %x\n", fmt);
	315	break;
	316	}
	317	return size;
	318	}
	319
	320	/*
	321	* TODO: this can be called multiple times for a single command if it
	322	* has very long data.
	323	*/
	324	int srp_transfer_data(struct scsi_cmnd sc, struct srp_cmd cmd,
	325	srp_rdma_t rdma_io, int dma_map, int ext_desc)
	326	{
	327	struct srp_direct_buf *md;
	328	struct srp_indirect_buf *id;
	329	enum dma_data_direction dir;
	330	int offset, err = 0;
	331	u8 format;
	332
78d85019	333	offset = cmd->add_cdb_len & ~3;
26b14823 FT	334
	335	dir = srp_cmd_direction(cmd);
	336	if (dir == DMA_FROM_DEVICE)
	337	offset += data_out_desc_size(cmd);
	338
	339	if (dir == DMA_TO_DEVICE)
	340	format = cmd->buf_fmt >> 4;
	341	else
	342	format = cmd->buf_fmt & ((1U << 4) - 1);
	343
	344	switch (format) {
	345	case SRP_NO_DATA_DESC:
	346	break;
	347	case SRP_DATA_DESC_DIRECT:
	348	md = (struct srp_direct_buf *)
	349	(cmd->add_data + offset);
	350	err = srp_direct_data(sc, md, dir, rdma_io, dma_map, ext_desc);
	351	break;
	352	case SRP_DATA_DESC_INDIRECT:
	353	id = (struct srp_indirect_buf *)
	354	(cmd->add_data + offset);
	355	err = srp_indirect_data(sc, cmd, id, dir, rdma_io, dma_map,
	356	ext_desc);
	357	break;
	358	default:
	359	eprintk("Unknown format %d %x\n", dir, format);
ad1331a7	360	err = -EINVAL;
26b14823 FT	361	}
	362
	363	return err;
	364	}
	365	EXPORT_SYMBOL_GPL(srp_transfer_data);
	366
	367	static int vscsis_data_length(struct srp_cmd *cmd, enum dma_data_direction dir)
	368	{
	369	struct srp_direct_buf *md;
	370	struct srp_indirect_buf *id;
78d85019	371	int len = 0, offset = cmd->add_cdb_len & ~3;
26b14823 FT	372	u8 fmt;
	373
	374	if (dir == DMA_TO_DEVICE)
	375	fmt = cmd->buf_fmt >> 4;
	376	else {
	377	fmt = cmd->buf_fmt & ((1U << 4) - 1);
	378	offset += data_out_desc_size(cmd);
	379	}
	380
	381	switch (fmt) {
	382	case SRP_NO_DATA_DESC:
	383	break;
	384	case SRP_DATA_DESC_DIRECT:
	385	md = (struct srp_direct_buf *) (cmd->add_data + offset);
	386	len = md->len;
	387	break;
	388	case SRP_DATA_DESC_INDIRECT:
	389	id = (struct srp_indirect_buf *) (cmd->add_data + offset);
	390	len = id->len;
	391	break;
	392	default:
	393	eprintk("invalid data format %x\n", fmt);
	394	break;
	395	}
	396	return len;
	397	}
	398
	399	int srp_cmd_queue(struct Scsi_Host shost, struct srp_cmd cmd, void *info,
17b0bcfa	400	u64 itn_id, u64 addr)
26b14823 FT	401	{
	402	enum dma_data_direction dir;
	403	struct scsi_cmnd *sc;
	404	int tag, len, err;
	405
	406	switch (cmd->task_attr) {
	407	case SRP_SIMPLE_TASK:
	408	tag = MSG_SIMPLE_TAG;
	409	break;
	410	case SRP_ORDERED_TASK:
	411	tag = MSG_ORDERED_TAG;
	412	break;
	413	case SRP_HEAD_TASK:
	414	tag = MSG_HEAD_TAG;
	415	break;
	416	default:
	417	eprintk("Task attribute %d not supported\n", cmd->task_attr);
	418	tag = MSG_ORDERED_TAG;
	419	}
	420
	421	dir = srp_cmd_direction(cmd);
	422	len = vscsis_data_length(cmd, dir);
	423
	424	dprintk("%p %x %lx %d %d %d %llx\n", info, cmd->cdb[0],
	425	cmd->lun, dir, len, tag, (unsigned long long) cmd->tag);
	426
	427	sc = scsi_host_get_command(shost, dir, GFP_KERNEL);
	428	if (!sc)
	429	return -ENOMEM;
	430
	431	sc->SCp.ptr = info;
	432	memcpy(sc->cmnd, cmd->cdb, MAX_COMMAND_SIZE);
30b0c37b BH	433	sc->sdb.length = len;
30b0c37b BH	434	sc->sdb.table.sgl = (void *) (unsigned long) addr;
26b14823	435	sc->tag = tag;
17b0bcfa FT	436	err = scsi_tgt_queue_command(sc, itn_id, (struct scsi_lun *)&cmd->lun,
17b0bcfa FT	437	cmd->tag);
26b14823 FT	438	if (err)
	439	scsi_host_put_command(shost, sc);
	440
	441	return err;
	442	}
	443	EXPORT_SYMBOL_GPL(srp_cmd_queue);
	444
40c4f3e4	445	MODULE_DESCRIPTION("SCSI RDMA Protocol lib functions");
26b14823 FT	446	MODULE_AUTHOR("FUJITA Tomonori");
26b14823 FT	447	MODULE_LICENSE("GPL");