[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, __FUNCTION__, __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);
	q->queue = kfifo_init((void *) q->pool, max * sizeof(void *),
			      GFP_KERNEL, &q->lock);
	if (IS_ERR(q->queue))
		goto free_item;

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

free_item:
	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]);
	}
}

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;
	target->dev->driver_data = 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 = sc->request_buffer;

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

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

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