blob: 732446e63963557dab5136c10c361acbc1a18a9a [file] [log] [blame]
FUJITA Tomonori26b14822006-12-01 03:00:50 +09001/*
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>
FUJITA Tomonori26b14822006-12-01 03:00:50 +090025#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
32enum 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...) \
41do { \
42 printk("%s(%d) " fmt, __FUNCTION__, __LINE__, ##args); \
43} while (0)
44/* #define dprintk eprintk */
45#define dprintk(fmt, args...)
46
47static 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
73free_item:
74 kfree(q->items);
75free_pool:
76 kfree(q->pool);
77 return -ENOMEM;
78}
79
80static void srp_iu_pool_free(struct srp_queue *q)
81{
82 kfree(q->items);
83 kfree(q->pool);
84}
85
86static 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
107out:
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
118static 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
129int 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
151free_ring:
152 srp_ring_free(target->dev, target->rx_ring, nr, iu_size);
153 return -ENOMEM;
154}
155EXPORT_SYMBOL_GPL(srp_target_alloc);
156
157void 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}
163EXPORT_SYMBOL_GPL(srp_target_free);
164
165struct 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}
177EXPORT_SYMBOL_GPL(srp_iu_get);
178
179void srp_iu_put(struct iu_entry *iue)
180{
181 kfifo_put(iue->target->iu_queue.queue, (void *) &iue, sizeof(void *));
182}
183EXPORT_SYMBOL_GPL(srp_iu_put);
184
185static 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
218static 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;
Bastian Blankad1331a2007-04-07 18:10:00 +0900227 int err = 0;
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900228 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;
FUJITA Tomonoribcd4e222007-05-11 19:10:45 +0900257 sg_dma_len(&dummy) = id->table_desc.len;
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900258 err = rdma_io(sc, &dummy, 1, &id->table_desc, 1, DMA_TO_DEVICE,
259 id->table_desc.len);
Bastian Blankad1331a2007-04-07 18:10:00 +0900260 if (err) {
261 eprintk("Error copying indirect table %d\n", err);
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900262 goto free_mem;
263 }
264 } else {
265 eprintk("This command uses external indirect buffer\n");
266 return -EINVAL;
267 }
268
269rdma:
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);
Bastian Blankad1331a2007-04-07 18:10:00 +0900274 err = -EIO;
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900275 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
286free_mem:
287 if (token && dma_map)
288 dma_free_coherent(iue->target->dev, id->table_desc.len, md, token);
289
Bastian Blankad1331a2007-04-07 18:10:00 +0900290 return err;
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900291}
292
293static 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 */
319int 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);
Bastian Blankad1331a2007-04-07 18:10:00 +0900355 err = -EINVAL;
FUJITA Tomonori26b14822006-12-01 03:00:50 +0900356 }
357
358 return err;
359}
360EXPORT_SYMBOL_GPL(srp_transfer_data);
361
362static 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
394int 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}
437EXPORT_SYMBOL_GPL(srp_cmd_queue);
438
439MODULE_DESCRIPTION("SCSI RDAM Protocol lib functions");
440MODULE_AUTHOR("FUJITA Tomonori");
441MODULE_LICENSE("GPL");