[GitHub/mt8127/android_kernel_alcatel_ttab.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 *));

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