atomic: use <linux/atomic.h>
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / infiniband / ulp / srp / ib_srp.c
1 /*
2 * Copyright (c) 2005 Cisco Systems. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/err.h>
37 #include <linux/string.h>
38 #include <linux/parser.h>
39 #include <linux/random.h>
40 #include <linux/jiffies.h>
41
42 #include <linux/atomic.h>
43
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_device.h>
46 #include <scsi/scsi_dbg.h>
47 #include <scsi/srp.h>
48 #include <scsi/scsi_transport_srp.h>
49
50 #include "ib_srp.h"
51
52 #define DRV_NAME "ib_srp"
53 #define PFX DRV_NAME ": "
54 #define DRV_VERSION "0.2"
55 #define DRV_RELDATE "November 1, 2005"
56
57 MODULE_AUTHOR("Roland Dreier");
58 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
59 "v" DRV_VERSION " (" DRV_RELDATE ")");
60 MODULE_LICENSE("Dual BSD/GPL");
61
62 static unsigned int srp_sg_tablesize;
63 static unsigned int cmd_sg_entries;
64 static unsigned int indirect_sg_entries;
65 static bool allow_ext_sg;
66 static int topspin_workarounds = 1;
67
68 module_param(srp_sg_tablesize, uint, 0444);
69 MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
70
71 module_param(cmd_sg_entries, uint, 0444);
72 MODULE_PARM_DESC(cmd_sg_entries,
73 "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
74
75 module_param(indirect_sg_entries, uint, 0444);
76 MODULE_PARM_DESC(indirect_sg_entries,
77 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");
78
79 module_param(allow_ext_sg, bool, 0444);
80 MODULE_PARM_DESC(allow_ext_sg,
81 "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");
82
83 module_param(topspin_workarounds, int, 0444);
84 MODULE_PARM_DESC(topspin_workarounds,
85 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
86
87 static void srp_add_one(struct ib_device *device);
88 static void srp_remove_one(struct ib_device *device);
89 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
90 static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
91 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
92
93 static struct scsi_transport_template *ib_srp_transport_template;
94
95 static struct ib_client srp_client = {
96 .name = "srp",
97 .add = srp_add_one,
98 .remove = srp_remove_one
99 };
100
101 static struct ib_sa_client srp_sa_client;
102
103 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
104 {
105 return (struct srp_target_port *) host->hostdata;
106 }
107
108 static const char *srp_target_info(struct Scsi_Host *host)
109 {
110 return host_to_target(host)->target_name;
111 }
112
113 static int srp_target_is_topspin(struct srp_target_port *target)
114 {
115 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
116 static const u8 cisco_oui[3] = { 0x00, 0x1b, 0x0d };
117
118 return topspin_workarounds &&
119 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
120 !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
121 }
122
123 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
124 gfp_t gfp_mask,
125 enum dma_data_direction direction)
126 {
127 struct srp_iu *iu;
128
129 iu = kmalloc(sizeof *iu, gfp_mask);
130 if (!iu)
131 goto out;
132
133 iu->buf = kzalloc(size, gfp_mask);
134 if (!iu->buf)
135 goto out_free_iu;
136
137 iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
138 direction);
139 if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
140 goto out_free_buf;
141
142 iu->size = size;
143 iu->direction = direction;
144
145 return iu;
146
147 out_free_buf:
148 kfree(iu->buf);
149 out_free_iu:
150 kfree(iu);
151 out:
152 return NULL;
153 }
154
155 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
156 {
157 if (!iu)
158 return;
159
160 ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
161 iu->direction);
162 kfree(iu->buf);
163 kfree(iu);
164 }
165
166 static void srp_qp_event(struct ib_event *event, void *context)
167 {
168 printk(KERN_ERR PFX "QP event %d\n", event->event);
169 }
170
171 static int srp_init_qp(struct srp_target_port *target,
172 struct ib_qp *qp)
173 {
174 struct ib_qp_attr *attr;
175 int ret;
176
177 attr = kmalloc(sizeof *attr, GFP_KERNEL);
178 if (!attr)
179 return -ENOMEM;
180
181 ret = ib_find_pkey(target->srp_host->srp_dev->dev,
182 target->srp_host->port,
183 be16_to_cpu(target->path.pkey),
184 &attr->pkey_index);
185 if (ret)
186 goto out;
187
188 attr->qp_state = IB_QPS_INIT;
189 attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
190 IB_ACCESS_REMOTE_WRITE);
191 attr->port_num = target->srp_host->port;
192
193 ret = ib_modify_qp(qp, attr,
194 IB_QP_STATE |
195 IB_QP_PKEY_INDEX |
196 IB_QP_ACCESS_FLAGS |
197 IB_QP_PORT);
198
199 out:
200 kfree(attr);
201 return ret;
202 }
203
204 static int srp_new_cm_id(struct srp_target_port *target)
205 {
206 struct ib_cm_id *new_cm_id;
207
208 new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
209 srp_cm_handler, target);
210 if (IS_ERR(new_cm_id))
211 return PTR_ERR(new_cm_id);
212
213 if (target->cm_id)
214 ib_destroy_cm_id(target->cm_id);
215 target->cm_id = new_cm_id;
216
217 return 0;
218 }
219
220 static int srp_create_target_ib(struct srp_target_port *target)
221 {
222 struct ib_qp_init_attr *init_attr;
223 int ret;
224
225 init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
226 if (!init_attr)
227 return -ENOMEM;
228
229 target->recv_cq = ib_create_cq(target->srp_host->srp_dev->dev,
230 srp_recv_completion, NULL, target, SRP_RQ_SIZE, 0);
231 if (IS_ERR(target->recv_cq)) {
232 ret = PTR_ERR(target->recv_cq);
233 goto err;
234 }
235
236 target->send_cq = ib_create_cq(target->srp_host->srp_dev->dev,
237 srp_send_completion, NULL, target, SRP_SQ_SIZE, 0);
238 if (IS_ERR(target->send_cq)) {
239 ret = PTR_ERR(target->send_cq);
240 goto err_recv_cq;
241 }
242
243 ib_req_notify_cq(target->recv_cq, IB_CQ_NEXT_COMP);
244
245 init_attr->event_handler = srp_qp_event;
246 init_attr->cap.max_send_wr = SRP_SQ_SIZE;
247 init_attr->cap.max_recv_wr = SRP_RQ_SIZE;
248 init_attr->cap.max_recv_sge = 1;
249 init_attr->cap.max_send_sge = 1;
250 init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
251 init_attr->qp_type = IB_QPT_RC;
252 init_attr->send_cq = target->send_cq;
253 init_attr->recv_cq = target->recv_cq;
254
255 target->qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
256 if (IS_ERR(target->qp)) {
257 ret = PTR_ERR(target->qp);
258 goto err_send_cq;
259 }
260
261 ret = srp_init_qp(target, target->qp);
262 if (ret)
263 goto err_qp;
264
265 kfree(init_attr);
266 return 0;
267
268 err_qp:
269 ib_destroy_qp(target->qp);
270
271 err_send_cq:
272 ib_destroy_cq(target->send_cq);
273
274 err_recv_cq:
275 ib_destroy_cq(target->recv_cq);
276
277 err:
278 kfree(init_attr);
279 return ret;
280 }
281
282 static void srp_free_target_ib(struct srp_target_port *target)
283 {
284 int i;
285
286 ib_destroy_qp(target->qp);
287 ib_destroy_cq(target->send_cq);
288 ib_destroy_cq(target->recv_cq);
289
290 for (i = 0; i < SRP_RQ_SIZE; ++i)
291 srp_free_iu(target->srp_host, target->rx_ring[i]);
292 for (i = 0; i < SRP_SQ_SIZE; ++i)
293 srp_free_iu(target->srp_host, target->tx_ring[i]);
294 }
295
296 static void srp_path_rec_completion(int status,
297 struct ib_sa_path_rec *pathrec,
298 void *target_ptr)
299 {
300 struct srp_target_port *target = target_ptr;
301
302 target->status = status;
303 if (status)
304 shost_printk(KERN_ERR, target->scsi_host,
305 PFX "Got failed path rec status %d\n", status);
306 else
307 target->path = *pathrec;
308 complete(&target->done);
309 }
310
311 static int srp_lookup_path(struct srp_target_port *target)
312 {
313 target->path.numb_path = 1;
314
315 init_completion(&target->done);
316
317 target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
318 target->srp_host->srp_dev->dev,
319 target->srp_host->port,
320 &target->path,
321 IB_SA_PATH_REC_SERVICE_ID |
322 IB_SA_PATH_REC_DGID |
323 IB_SA_PATH_REC_SGID |
324 IB_SA_PATH_REC_NUMB_PATH |
325 IB_SA_PATH_REC_PKEY,
326 SRP_PATH_REC_TIMEOUT_MS,
327 GFP_KERNEL,
328 srp_path_rec_completion,
329 target, &target->path_query);
330 if (target->path_query_id < 0)
331 return target->path_query_id;
332
333 wait_for_completion(&target->done);
334
335 if (target->status < 0)
336 shost_printk(KERN_WARNING, target->scsi_host,
337 PFX "Path record query failed\n");
338
339 return target->status;
340 }
341
342 static int srp_send_req(struct srp_target_port *target)
343 {
344 struct {
345 struct ib_cm_req_param param;
346 struct srp_login_req priv;
347 } *req = NULL;
348 int status;
349
350 req = kzalloc(sizeof *req, GFP_KERNEL);
351 if (!req)
352 return -ENOMEM;
353
354 req->param.primary_path = &target->path;
355 req->param.alternate_path = NULL;
356 req->param.service_id = target->service_id;
357 req->param.qp_num = target->qp->qp_num;
358 req->param.qp_type = target->qp->qp_type;
359 req->param.private_data = &req->priv;
360 req->param.private_data_len = sizeof req->priv;
361 req->param.flow_control = 1;
362
363 get_random_bytes(&req->param.starting_psn, 4);
364 req->param.starting_psn &= 0xffffff;
365
366 /*
367 * Pick some arbitrary defaults here; we could make these
368 * module parameters if anyone cared about setting them.
369 */
370 req->param.responder_resources = 4;
371 req->param.remote_cm_response_timeout = 20;
372 req->param.local_cm_response_timeout = 20;
373 req->param.retry_count = 7;
374 req->param.rnr_retry_count = 7;
375 req->param.max_cm_retries = 15;
376
377 req->priv.opcode = SRP_LOGIN_REQ;
378 req->priv.tag = 0;
379 req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
380 req->priv.req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
381 SRP_BUF_FORMAT_INDIRECT);
382 /*
383 * In the published SRP specification (draft rev. 16a), the
384 * port identifier format is 8 bytes of ID extension followed
385 * by 8 bytes of GUID. Older drafts put the two halves in the
386 * opposite order, so that the GUID comes first.
387 *
388 * Targets conforming to these obsolete drafts can be
389 * recognized by the I/O Class they report.
390 */
391 if (target->io_class == SRP_REV10_IB_IO_CLASS) {
392 memcpy(req->priv.initiator_port_id,
393 &target->path.sgid.global.interface_id, 8);
394 memcpy(req->priv.initiator_port_id + 8,
395 &target->initiator_ext, 8);
396 memcpy(req->priv.target_port_id, &target->ioc_guid, 8);
397 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
398 } else {
399 memcpy(req->priv.initiator_port_id,
400 &target->initiator_ext, 8);
401 memcpy(req->priv.initiator_port_id + 8,
402 &target->path.sgid.global.interface_id, 8);
403 memcpy(req->priv.target_port_id, &target->id_ext, 8);
404 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
405 }
406
407 /*
408 * Topspin/Cisco SRP targets will reject our login unless we
409 * zero out the first 8 bytes of our initiator port ID and set
410 * the second 8 bytes to the local node GUID.
411 */
412 if (srp_target_is_topspin(target)) {
413 shost_printk(KERN_DEBUG, target->scsi_host,
414 PFX "Topspin/Cisco initiator port ID workaround "
415 "activated for target GUID %016llx\n",
416 (unsigned long long) be64_to_cpu(target->ioc_guid));
417 memset(req->priv.initiator_port_id, 0, 8);
418 memcpy(req->priv.initiator_port_id + 8,
419 &target->srp_host->srp_dev->dev->node_guid, 8);
420 }
421
422 status = ib_send_cm_req(target->cm_id, &req->param);
423
424 kfree(req);
425
426 return status;
427 }
428
429 static void srp_disconnect_target(struct srp_target_port *target)
430 {
431 /* XXX should send SRP_I_LOGOUT request */
432
433 init_completion(&target->done);
434 if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
435 shost_printk(KERN_DEBUG, target->scsi_host,
436 PFX "Sending CM DREQ failed\n");
437 return;
438 }
439 wait_for_completion(&target->done);
440 }
441
442 static bool srp_change_state(struct srp_target_port *target,
443 enum srp_target_state old,
444 enum srp_target_state new)
445 {
446 bool changed = false;
447
448 spin_lock_irq(&target->lock);
449 if (target->state == old) {
450 target->state = new;
451 changed = true;
452 }
453 spin_unlock_irq(&target->lock);
454 return changed;
455 }
456
457 static void srp_free_req_data(struct srp_target_port *target)
458 {
459 struct ib_device *ibdev = target->srp_host->srp_dev->dev;
460 struct srp_request *req;
461 int i;
462
463 for (i = 0, req = target->req_ring; i < SRP_CMD_SQ_SIZE; ++i, ++req) {
464 kfree(req->fmr_list);
465 kfree(req->map_page);
466 if (req->indirect_dma_addr) {
467 ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
468 target->indirect_size,
469 DMA_TO_DEVICE);
470 }
471 kfree(req->indirect_desc);
472 }
473 }
474
475 static void srp_remove_work(struct work_struct *work)
476 {
477 struct srp_target_port *target =
478 container_of(work, struct srp_target_port, work);
479
480 if (!srp_change_state(target, SRP_TARGET_DEAD, SRP_TARGET_REMOVED))
481 return;
482
483 spin_lock(&target->srp_host->target_lock);
484 list_del(&target->list);
485 spin_unlock(&target->srp_host->target_lock);
486
487 srp_remove_host(target->scsi_host);
488 scsi_remove_host(target->scsi_host);
489 ib_destroy_cm_id(target->cm_id);
490 srp_free_target_ib(target);
491 srp_free_req_data(target);
492 scsi_host_put(target->scsi_host);
493 }
494
495 static int srp_connect_target(struct srp_target_port *target)
496 {
497 int retries = 3;
498 int ret;
499
500 ret = srp_lookup_path(target);
501 if (ret)
502 return ret;
503
504 while (1) {
505 init_completion(&target->done);
506 ret = srp_send_req(target);
507 if (ret)
508 return ret;
509 wait_for_completion(&target->done);
510
511 /*
512 * The CM event handling code will set status to
513 * SRP_PORT_REDIRECT if we get a port redirect REJ
514 * back, or SRP_DLID_REDIRECT if we get a lid/qp
515 * redirect REJ back.
516 */
517 switch (target->status) {
518 case 0:
519 return 0;
520
521 case SRP_PORT_REDIRECT:
522 ret = srp_lookup_path(target);
523 if (ret)
524 return ret;
525 break;
526
527 case SRP_DLID_REDIRECT:
528 break;
529
530 case SRP_STALE_CONN:
531 /* Our current CM id was stale, and is now in timewait.
532 * Try to reconnect with a new one.
533 */
534 if (!retries-- || srp_new_cm_id(target)) {
535 shost_printk(KERN_ERR, target->scsi_host, PFX
536 "giving up on stale connection\n");
537 target->status = -ECONNRESET;
538 return target->status;
539 }
540
541 shost_printk(KERN_ERR, target->scsi_host, PFX
542 "retrying stale connection\n");
543 break;
544
545 default:
546 return target->status;
547 }
548 }
549 }
550
551 static void srp_unmap_data(struct scsi_cmnd *scmnd,
552 struct srp_target_port *target,
553 struct srp_request *req)
554 {
555 struct ib_device *ibdev = target->srp_host->srp_dev->dev;
556 struct ib_pool_fmr **pfmr;
557
558 if (!scsi_sglist(scmnd) ||
559 (scmnd->sc_data_direction != DMA_TO_DEVICE &&
560 scmnd->sc_data_direction != DMA_FROM_DEVICE))
561 return;
562
563 pfmr = req->fmr_list;
564 while (req->nfmr--)
565 ib_fmr_pool_unmap(*pfmr++);
566
567 ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
568 scmnd->sc_data_direction);
569 }
570
571 static void srp_remove_req(struct srp_target_port *target,
572 struct srp_request *req, s32 req_lim_delta)
573 {
574 unsigned long flags;
575
576 srp_unmap_data(req->scmnd, target, req);
577 spin_lock_irqsave(&target->lock, flags);
578 target->req_lim += req_lim_delta;
579 req->scmnd = NULL;
580 list_add_tail(&req->list, &target->free_reqs);
581 spin_unlock_irqrestore(&target->lock, flags);
582 }
583
584 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
585 {
586 req->scmnd->result = DID_RESET << 16;
587 req->scmnd->scsi_done(req->scmnd);
588 srp_remove_req(target, req, 0);
589 }
590
591 static int srp_reconnect_target(struct srp_target_port *target)
592 {
593 struct ib_qp_attr qp_attr;
594 struct ib_wc wc;
595 int i, ret;
596
597 if (!srp_change_state(target, SRP_TARGET_LIVE, SRP_TARGET_CONNECTING))
598 return -EAGAIN;
599
600 srp_disconnect_target(target);
601 /*
602 * Now get a new local CM ID so that we avoid confusing the
603 * target in case things are really fouled up.
604 */
605 ret = srp_new_cm_id(target);
606 if (ret)
607 goto err;
608
609 qp_attr.qp_state = IB_QPS_RESET;
610 ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
611 if (ret)
612 goto err;
613
614 ret = srp_init_qp(target, target->qp);
615 if (ret)
616 goto err;
617
618 while (ib_poll_cq(target->recv_cq, 1, &wc) > 0)
619 ; /* nothing */
620 while (ib_poll_cq(target->send_cq, 1, &wc) > 0)
621 ; /* nothing */
622
623 for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
624 struct srp_request *req = &target->req_ring[i];
625 if (req->scmnd)
626 srp_reset_req(target, req);
627 }
628
629 INIT_LIST_HEAD(&target->free_tx);
630 for (i = 0; i < SRP_SQ_SIZE; ++i)
631 list_add(&target->tx_ring[i]->list, &target->free_tx);
632
633 target->qp_in_error = 0;
634 ret = srp_connect_target(target);
635 if (ret)
636 goto err;
637
638 if (!srp_change_state(target, SRP_TARGET_CONNECTING, SRP_TARGET_LIVE))
639 ret = -EAGAIN;
640
641 return ret;
642
643 err:
644 shost_printk(KERN_ERR, target->scsi_host,
645 PFX "reconnect failed (%d), removing target port.\n", ret);
646
647 /*
648 * We couldn't reconnect, so kill our target port off.
649 * However, we have to defer the real removal because we
650 * are in the context of the SCSI error handler now, which
651 * will deadlock if we call scsi_remove_host().
652 *
653 * Schedule our work inside the lock to avoid a race with
654 * the flush_scheduled_work() in srp_remove_one().
655 */
656 spin_lock_irq(&target->lock);
657 if (target->state == SRP_TARGET_CONNECTING) {
658 target->state = SRP_TARGET_DEAD;
659 INIT_WORK(&target->work, srp_remove_work);
660 queue_work(ib_wq, &target->work);
661 }
662 spin_unlock_irq(&target->lock);
663
664 return ret;
665 }
666
667 static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
668 unsigned int dma_len, u32 rkey)
669 {
670 struct srp_direct_buf *desc = state->desc;
671
672 desc->va = cpu_to_be64(dma_addr);
673 desc->key = cpu_to_be32(rkey);
674 desc->len = cpu_to_be32(dma_len);
675
676 state->total_len += dma_len;
677 state->desc++;
678 state->ndesc++;
679 }
680
681 static int srp_map_finish_fmr(struct srp_map_state *state,
682 struct srp_target_port *target)
683 {
684 struct srp_device *dev = target->srp_host->srp_dev;
685 struct ib_pool_fmr *fmr;
686 u64 io_addr = 0;
687
688 if (!state->npages)
689 return 0;
690
691 if (state->npages == 1) {
692 srp_map_desc(state, state->base_dma_addr, state->fmr_len,
693 target->rkey);
694 state->npages = state->fmr_len = 0;
695 return 0;
696 }
697
698 fmr = ib_fmr_pool_map_phys(dev->fmr_pool, state->pages,
699 state->npages, io_addr);
700 if (IS_ERR(fmr))
701 return PTR_ERR(fmr);
702
703 *state->next_fmr++ = fmr;
704 state->nfmr++;
705
706 srp_map_desc(state, 0, state->fmr_len, fmr->fmr->rkey);
707 state->npages = state->fmr_len = 0;
708 return 0;
709 }
710
711 static void srp_map_update_start(struct srp_map_state *state,
712 struct scatterlist *sg, int sg_index,
713 dma_addr_t dma_addr)
714 {
715 state->unmapped_sg = sg;
716 state->unmapped_index = sg_index;
717 state->unmapped_addr = dma_addr;
718 }
719
720 static int srp_map_sg_entry(struct srp_map_state *state,
721 struct srp_target_port *target,
722 struct scatterlist *sg, int sg_index,
723 int use_fmr)
724 {
725 struct srp_device *dev = target->srp_host->srp_dev;
726 struct ib_device *ibdev = dev->dev;
727 dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
728 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
729 unsigned int len;
730 int ret;
731
732 if (!dma_len)
733 return 0;
734
735 if (use_fmr == SRP_MAP_NO_FMR) {
736 /* Once we're in direct map mode for a request, we don't
737 * go back to FMR mode, so no need to update anything
738 * other than the descriptor.
739 */
740 srp_map_desc(state, dma_addr, dma_len, target->rkey);
741 return 0;
742 }
743
744 /* If we start at an offset into the FMR page, don't merge into
745 * the current FMR. Finish it out, and use the kernel's MR for this
746 * sg entry. This is to avoid potential bugs on some SRP targets
747 * that were never quite defined, but went away when the initiator
748 * avoided using FMR on such page fragments.
749 */
750 if (dma_addr & ~dev->fmr_page_mask || dma_len > dev->fmr_max_size) {
751 ret = srp_map_finish_fmr(state, target);
752 if (ret)
753 return ret;
754
755 srp_map_desc(state, dma_addr, dma_len, target->rkey);
756 srp_map_update_start(state, NULL, 0, 0);
757 return 0;
758 }
759
760 /* If this is the first sg to go into the FMR, save our position.
761 * We need to know the first unmapped entry, its index, and the
762 * first unmapped address within that entry to be able to restart
763 * mapping after an error.
764 */
765 if (!state->unmapped_sg)
766 srp_map_update_start(state, sg, sg_index, dma_addr);
767
768 while (dma_len) {
769 if (state->npages == SRP_FMR_SIZE) {
770 ret = srp_map_finish_fmr(state, target);
771 if (ret)
772 return ret;
773
774 srp_map_update_start(state, sg, sg_index, dma_addr);
775 }
776
777 len = min_t(unsigned int, dma_len, dev->fmr_page_size);
778
779 if (!state->npages)
780 state->base_dma_addr = dma_addr;
781 state->pages[state->npages++] = dma_addr;
782 state->fmr_len += len;
783 dma_addr += len;
784 dma_len -= len;
785 }
786
787 /* If the last entry of the FMR wasn't a full page, then we need to
788 * close it out and start a new one -- we can only merge at page
789 * boundries.
790 */
791 ret = 0;
792 if (len != dev->fmr_page_size) {
793 ret = srp_map_finish_fmr(state, target);
794 if (!ret)
795 srp_map_update_start(state, NULL, 0, 0);
796 }
797 return ret;
798 }
799
800 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
801 struct srp_request *req)
802 {
803 struct scatterlist *scat, *sg;
804 struct srp_cmd *cmd = req->cmd->buf;
805 int i, len, nents, count, use_fmr;
806 struct srp_device *dev;
807 struct ib_device *ibdev;
808 struct srp_map_state state;
809 struct srp_indirect_buf *indirect_hdr;
810 u32 table_len;
811 u8 fmt;
812
813 if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
814 return sizeof (struct srp_cmd);
815
816 if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
817 scmnd->sc_data_direction != DMA_TO_DEVICE) {
818 shost_printk(KERN_WARNING, target->scsi_host,
819 PFX "Unhandled data direction %d\n",
820 scmnd->sc_data_direction);
821 return -EINVAL;
822 }
823
824 nents = scsi_sg_count(scmnd);
825 scat = scsi_sglist(scmnd);
826
827 dev = target->srp_host->srp_dev;
828 ibdev = dev->dev;
829
830 count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
831 if (unlikely(count == 0))
832 return -EIO;
833
834 fmt = SRP_DATA_DESC_DIRECT;
835 len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
836
837 if (count == 1) {
838 /*
839 * The midlayer only generated a single gather/scatter
840 * entry, or DMA mapping coalesced everything to a
841 * single entry. So a direct descriptor along with
842 * the DMA MR suffices.
843 */
844 struct srp_direct_buf *buf = (void *) cmd->add_data;
845
846 buf->va = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
847 buf->key = cpu_to_be32(target->rkey);
848 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
849
850 req->nfmr = 0;
851 goto map_complete;
852 }
853
854 /* We have more than one scatter/gather entry, so build our indirect
855 * descriptor table, trying to merge as many entries with FMR as we
856 * can.
857 */
858 indirect_hdr = (void *) cmd->add_data;
859
860 ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
861 target->indirect_size, DMA_TO_DEVICE);
862
863 memset(&state, 0, sizeof(state));
864 state.desc = req->indirect_desc;
865 state.pages = req->map_page;
866 state.next_fmr = req->fmr_list;
867
868 use_fmr = dev->fmr_pool ? SRP_MAP_ALLOW_FMR : SRP_MAP_NO_FMR;
869
870 for_each_sg(scat, sg, count, i) {
871 if (srp_map_sg_entry(&state, target, sg, i, use_fmr)) {
872 /* FMR mapping failed, so backtrack to the first
873 * unmapped entry and continue on without using FMR.
874 */
875 dma_addr_t dma_addr;
876 unsigned int dma_len;
877
878 backtrack:
879 sg = state.unmapped_sg;
880 i = state.unmapped_index;
881
882 dma_addr = ib_sg_dma_address(ibdev, sg);
883 dma_len = ib_sg_dma_len(ibdev, sg);
884 dma_len -= (state.unmapped_addr - dma_addr);
885 dma_addr = state.unmapped_addr;
886 use_fmr = SRP_MAP_NO_FMR;
887 srp_map_desc(&state, dma_addr, dma_len, target->rkey);
888 }
889 }
890
891 if (use_fmr == SRP_MAP_ALLOW_FMR && srp_map_finish_fmr(&state, target))
892 goto backtrack;
893
894 /* We've mapped the request, now pull as much of the indirect
895 * descriptor table as we can into the command buffer. If this
896 * target is not using an external indirect table, we are
897 * guaranteed to fit into the command, as the SCSI layer won't
898 * give us more S/G entries than we allow.
899 */
900 req->nfmr = state.nfmr;
901 if (state.ndesc == 1) {
902 /* FMR mapping was able to collapse this to one entry,
903 * so use a direct descriptor.
904 */
905 struct srp_direct_buf *buf = (void *) cmd->add_data;
906
907 *buf = req->indirect_desc[0];
908 goto map_complete;
909 }
910
911 if (unlikely(target->cmd_sg_cnt < state.ndesc &&
912 !target->allow_ext_sg)) {
913 shost_printk(KERN_ERR, target->scsi_host,
914 "Could not fit S/G list into SRP_CMD\n");
915 return -EIO;
916 }
917
918 count = min(state.ndesc, target->cmd_sg_cnt);
919 table_len = state.ndesc * sizeof (struct srp_direct_buf);
920
921 fmt = SRP_DATA_DESC_INDIRECT;
922 len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
923 len += count * sizeof (struct srp_direct_buf);
924
925 memcpy(indirect_hdr->desc_list, req->indirect_desc,
926 count * sizeof (struct srp_direct_buf));
927
928 indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
929 indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
930 indirect_hdr->table_desc.len = cpu_to_be32(table_len);
931 indirect_hdr->len = cpu_to_be32(state.total_len);
932
933 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
934 cmd->data_out_desc_cnt = count;
935 else
936 cmd->data_in_desc_cnt = count;
937
938 ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
939 DMA_TO_DEVICE);
940
941 map_complete:
942 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
943 cmd->buf_fmt = fmt << 4;
944 else
945 cmd->buf_fmt = fmt;
946
947 return len;
948 }
949
950 /*
951 * Return an IU and possible credit to the free pool
952 */
953 static void srp_put_tx_iu(struct srp_target_port *target, struct srp_iu *iu,
954 enum srp_iu_type iu_type)
955 {
956 unsigned long flags;
957
958 spin_lock_irqsave(&target->lock, flags);
959 list_add(&iu->list, &target->free_tx);
960 if (iu_type != SRP_IU_RSP)
961 ++target->req_lim;
962 spin_unlock_irqrestore(&target->lock, flags);
963 }
964
965 /*
966 * Must be called with target->lock held to protect req_lim and free_tx.
967 * If IU is not sent, it must be returned using srp_put_tx_iu().
968 *
969 * Note:
970 * An upper limit for the number of allocated information units for each
971 * request type is:
972 * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
973 * more than Scsi_Host.can_queue requests.
974 * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
975 * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
976 * one unanswered SRP request to an initiator.
977 */
978 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
979 enum srp_iu_type iu_type)
980 {
981 s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
982 struct srp_iu *iu;
983
984 srp_send_completion(target->send_cq, target);
985
986 if (list_empty(&target->free_tx))
987 return NULL;
988
989 /* Initiator responses to target requests do not consume credits */
990 if (iu_type != SRP_IU_RSP) {
991 if (target->req_lim <= rsv) {
992 ++target->zero_req_lim;
993 return NULL;
994 }
995
996 --target->req_lim;
997 }
998
999 iu = list_first_entry(&target->free_tx, struct srp_iu, list);
1000 list_del(&iu->list);
1001 return iu;
1002 }
1003
1004 static int srp_post_send(struct srp_target_port *target,
1005 struct srp_iu *iu, int len)
1006 {
1007 struct ib_sge list;
1008 struct ib_send_wr wr, *bad_wr;
1009
1010 list.addr = iu->dma;
1011 list.length = len;
1012 list.lkey = target->lkey;
1013
1014 wr.next = NULL;
1015 wr.wr_id = (uintptr_t) iu;
1016 wr.sg_list = &list;
1017 wr.num_sge = 1;
1018 wr.opcode = IB_WR_SEND;
1019 wr.send_flags = IB_SEND_SIGNALED;
1020
1021 return ib_post_send(target->qp, &wr, &bad_wr);
1022 }
1023
1024 static int srp_post_recv(struct srp_target_port *target, struct srp_iu *iu)
1025 {
1026 struct ib_recv_wr wr, *bad_wr;
1027 struct ib_sge list;
1028
1029 list.addr = iu->dma;
1030 list.length = iu->size;
1031 list.lkey = target->lkey;
1032
1033 wr.next = NULL;
1034 wr.wr_id = (uintptr_t) iu;
1035 wr.sg_list = &list;
1036 wr.num_sge = 1;
1037
1038 return ib_post_recv(target->qp, &wr, &bad_wr);
1039 }
1040
1041 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
1042 {
1043 struct srp_request *req;
1044 struct scsi_cmnd *scmnd;
1045 unsigned long flags;
1046
1047 if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1048 spin_lock_irqsave(&target->lock, flags);
1049 target->req_lim += be32_to_cpu(rsp->req_lim_delta);
1050 spin_unlock_irqrestore(&target->lock, flags);
1051
1052 target->tsk_mgmt_status = -1;
1053 if (be32_to_cpu(rsp->resp_data_len) >= 4)
1054 target->tsk_mgmt_status = rsp->data[3];
1055 complete(&target->tsk_mgmt_done);
1056 } else {
1057 req = &target->req_ring[rsp->tag];
1058 scmnd = req->scmnd;
1059 if (!scmnd)
1060 shost_printk(KERN_ERR, target->scsi_host,
1061 "Null scmnd for RSP w/tag %016llx\n",
1062 (unsigned long long) rsp->tag);
1063 scmnd->result = rsp->status;
1064
1065 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
1066 memcpy(scmnd->sense_buffer, rsp->data +
1067 be32_to_cpu(rsp->resp_data_len),
1068 min_t(int, be32_to_cpu(rsp->sense_data_len),
1069 SCSI_SENSE_BUFFERSIZE));
1070 }
1071
1072 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
1073 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
1074 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
1075 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
1076
1077 srp_remove_req(target, req, be32_to_cpu(rsp->req_lim_delta));
1078 scmnd->host_scribble = NULL;
1079 scmnd->scsi_done(scmnd);
1080 }
1081 }
1082
1083 static int srp_response_common(struct srp_target_port *target, s32 req_delta,
1084 void *rsp, int len)
1085 {
1086 struct ib_device *dev = target->srp_host->srp_dev->dev;
1087 unsigned long flags;
1088 struct srp_iu *iu;
1089 int err;
1090
1091 spin_lock_irqsave(&target->lock, flags);
1092 target->req_lim += req_delta;
1093 iu = __srp_get_tx_iu(target, SRP_IU_RSP);
1094 spin_unlock_irqrestore(&target->lock, flags);
1095
1096 if (!iu) {
1097 shost_printk(KERN_ERR, target->scsi_host, PFX
1098 "no IU available to send response\n");
1099 return 1;
1100 }
1101
1102 ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
1103 memcpy(iu->buf, rsp, len);
1104 ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
1105
1106 err = srp_post_send(target, iu, len);
1107 if (err) {
1108 shost_printk(KERN_ERR, target->scsi_host, PFX
1109 "unable to post response: %d\n", err);
1110 srp_put_tx_iu(target, iu, SRP_IU_RSP);
1111 }
1112
1113 return err;
1114 }
1115
1116 static void srp_process_cred_req(struct srp_target_port *target,
1117 struct srp_cred_req *req)
1118 {
1119 struct srp_cred_rsp rsp = {
1120 .opcode = SRP_CRED_RSP,
1121 .tag = req->tag,
1122 };
1123 s32 delta = be32_to_cpu(req->req_lim_delta);
1124
1125 if (srp_response_common(target, delta, &rsp, sizeof rsp))
1126 shost_printk(KERN_ERR, target->scsi_host, PFX
1127 "problems processing SRP_CRED_REQ\n");
1128 }
1129
1130 static void srp_process_aer_req(struct srp_target_port *target,
1131 struct srp_aer_req *req)
1132 {
1133 struct srp_aer_rsp rsp = {
1134 .opcode = SRP_AER_RSP,
1135 .tag = req->tag,
1136 };
1137 s32 delta = be32_to_cpu(req->req_lim_delta);
1138
1139 shost_printk(KERN_ERR, target->scsi_host, PFX
1140 "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
1141
1142 if (srp_response_common(target, delta, &rsp, sizeof rsp))
1143 shost_printk(KERN_ERR, target->scsi_host, PFX
1144 "problems processing SRP_AER_REQ\n");
1145 }
1146
1147 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
1148 {
1149 struct ib_device *dev = target->srp_host->srp_dev->dev;
1150 struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
1151 int res;
1152 u8 opcode;
1153
1154 ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
1155 DMA_FROM_DEVICE);
1156
1157 opcode = *(u8 *) iu->buf;
1158
1159 if (0) {
1160 shost_printk(KERN_ERR, target->scsi_host,
1161 PFX "recv completion, opcode 0x%02x\n", opcode);
1162 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1163 iu->buf, wc->byte_len, true);
1164 }
1165
1166 switch (opcode) {
1167 case SRP_RSP:
1168 srp_process_rsp(target, iu->buf);
1169 break;
1170
1171 case SRP_CRED_REQ:
1172 srp_process_cred_req(target, iu->buf);
1173 break;
1174
1175 case SRP_AER_REQ:
1176 srp_process_aer_req(target, iu->buf);
1177 break;
1178
1179 case SRP_T_LOGOUT:
1180 /* XXX Handle target logout */
1181 shost_printk(KERN_WARNING, target->scsi_host,
1182 PFX "Got target logout request\n");
1183 break;
1184
1185 default:
1186 shost_printk(KERN_WARNING, target->scsi_host,
1187 PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1188 break;
1189 }
1190
1191 ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
1192 DMA_FROM_DEVICE);
1193
1194 res = srp_post_recv(target, iu);
1195 if (res != 0)
1196 shost_printk(KERN_ERR, target->scsi_host,
1197 PFX "Recv failed with error code %d\n", res);
1198 }
1199
1200 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
1201 {
1202 struct srp_target_port *target = target_ptr;
1203 struct ib_wc wc;
1204
1205 ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1206 while (ib_poll_cq(cq, 1, &wc) > 0) {
1207 if (wc.status) {
1208 shost_printk(KERN_ERR, target->scsi_host,
1209 PFX "failed receive status %d\n",
1210 wc.status);
1211 target->qp_in_error = 1;
1212 break;
1213 }
1214
1215 srp_handle_recv(target, &wc);
1216 }
1217 }
1218
1219 static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
1220 {
1221 struct srp_target_port *target = target_ptr;
1222 struct ib_wc wc;
1223 struct srp_iu *iu;
1224
1225 while (ib_poll_cq(cq, 1, &wc) > 0) {
1226 if (wc.status) {
1227 shost_printk(KERN_ERR, target->scsi_host,
1228 PFX "failed send status %d\n",
1229 wc.status);
1230 target->qp_in_error = 1;
1231 break;
1232 }
1233
1234 iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
1235 list_add(&iu->list, &target->free_tx);
1236 }
1237 }
1238
1239 static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1240 {
1241 struct srp_target_port *target = host_to_target(shost);
1242 struct srp_request *req;
1243 struct srp_iu *iu;
1244 struct srp_cmd *cmd;
1245 struct ib_device *dev;
1246 unsigned long flags;
1247 int len;
1248
1249 if (target->state == SRP_TARGET_CONNECTING)
1250 goto err;
1251
1252 if (target->state == SRP_TARGET_DEAD ||
1253 target->state == SRP_TARGET_REMOVED) {
1254 scmnd->result = DID_BAD_TARGET << 16;
1255 scmnd->scsi_done(scmnd);
1256 return 0;
1257 }
1258
1259 spin_lock_irqsave(&target->lock, flags);
1260 iu = __srp_get_tx_iu(target, SRP_IU_CMD);
1261 if (!iu)
1262 goto err_unlock;
1263
1264 req = list_first_entry(&target->free_reqs, struct srp_request, list);
1265 list_del(&req->list);
1266 spin_unlock_irqrestore(&target->lock, flags);
1267
1268 dev = target->srp_host->srp_dev->dev;
1269 ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
1270 DMA_TO_DEVICE);
1271
1272 scmnd->result = 0;
1273 scmnd->host_scribble = (void *) req;
1274
1275 cmd = iu->buf;
1276 memset(cmd, 0, sizeof *cmd);
1277
1278 cmd->opcode = SRP_CMD;
1279 cmd->lun = cpu_to_be64((u64) scmnd->device->lun << 48);
1280 cmd->tag = req->index;
1281 memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1282
1283 req->scmnd = scmnd;
1284 req->cmd = iu;
1285
1286 len = srp_map_data(scmnd, target, req);
1287 if (len < 0) {
1288 shost_printk(KERN_ERR, target->scsi_host,
1289 PFX "Failed to map data\n");
1290 goto err_iu;
1291 }
1292
1293 ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
1294 DMA_TO_DEVICE);
1295
1296 if (srp_post_send(target, iu, len)) {
1297 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1298 goto err_unmap;
1299 }
1300
1301 return 0;
1302
1303 err_unmap:
1304 srp_unmap_data(scmnd, target, req);
1305
1306 err_iu:
1307 srp_put_tx_iu(target, iu, SRP_IU_CMD);
1308
1309 spin_lock_irqsave(&target->lock, flags);
1310 list_add(&req->list, &target->free_reqs);
1311
1312 err_unlock:
1313 spin_unlock_irqrestore(&target->lock, flags);
1314
1315 err:
1316 return SCSI_MLQUEUE_HOST_BUSY;
1317 }
1318
1319 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1320 {
1321 int i;
1322
1323 for (i = 0; i < SRP_RQ_SIZE; ++i) {
1324 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1325 target->max_ti_iu_len,
1326 GFP_KERNEL, DMA_FROM_DEVICE);
1327 if (!target->rx_ring[i])
1328 goto err;
1329 }
1330
1331 for (i = 0; i < SRP_SQ_SIZE; ++i) {
1332 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1333 target->max_iu_len,
1334 GFP_KERNEL, DMA_TO_DEVICE);
1335 if (!target->tx_ring[i])
1336 goto err;
1337
1338 list_add(&target->tx_ring[i]->list, &target->free_tx);
1339 }
1340
1341 return 0;
1342
1343 err:
1344 for (i = 0; i < SRP_RQ_SIZE; ++i) {
1345 srp_free_iu(target->srp_host, target->rx_ring[i]);
1346 target->rx_ring[i] = NULL;
1347 }
1348
1349 for (i = 0; i < SRP_SQ_SIZE; ++i) {
1350 srp_free_iu(target->srp_host, target->tx_ring[i]);
1351 target->tx_ring[i] = NULL;
1352 }
1353
1354 return -ENOMEM;
1355 }
1356
1357 static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
1358 struct srp_login_rsp *lrsp,
1359 struct srp_target_port *target)
1360 {
1361 struct ib_qp_attr *qp_attr = NULL;
1362 int attr_mask = 0;
1363 int ret;
1364 int i;
1365
1366 if (lrsp->opcode == SRP_LOGIN_RSP) {
1367 target->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
1368 target->req_lim = be32_to_cpu(lrsp->req_lim_delta);
1369
1370 /*
1371 * Reserve credits for task management so we don't
1372 * bounce requests back to the SCSI mid-layer.
1373 */
1374 target->scsi_host->can_queue
1375 = min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
1376 target->scsi_host->can_queue);
1377 } else {
1378 shost_printk(KERN_WARNING, target->scsi_host,
1379 PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
1380 ret = -ECONNRESET;
1381 goto error;
1382 }
1383
1384 if (!target->rx_ring[0]) {
1385 ret = srp_alloc_iu_bufs(target);
1386 if (ret)
1387 goto error;
1388 }
1389
1390 ret = -ENOMEM;
1391 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1392 if (!qp_attr)
1393 goto error;
1394
1395 qp_attr->qp_state = IB_QPS_RTR;
1396 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1397 if (ret)
1398 goto error_free;
1399
1400 ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
1401 if (ret)
1402 goto error_free;
1403
1404 for (i = 0; i < SRP_RQ_SIZE; i++) {
1405 struct srp_iu *iu = target->rx_ring[i];
1406 ret = srp_post_recv(target, iu);
1407 if (ret)
1408 goto error_free;
1409 }
1410
1411 qp_attr->qp_state = IB_QPS_RTS;
1412 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1413 if (ret)
1414 goto error_free;
1415
1416 ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
1417 if (ret)
1418 goto error_free;
1419
1420 ret = ib_send_cm_rtu(cm_id, NULL, 0);
1421
1422 error_free:
1423 kfree(qp_attr);
1424
1425 error:
1426 target->status = ret;
1427 }
1428
1429 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1430 struct ib_cm_event *event,
1431 struct srp_target_port *target)
1432 {
1433 struct Scsi_Host *shost = target->scsi_host;
1434 struct ib_class_port_info *cpi;
1435 int opcode;
1436
1437 switch (event->param.rej_rcvd.reason) {
1438 case IB_CM_REJ_PORT_CM_REDIRECT:
1439 cpi = event->param.rej_rcvd.ari;
1440 target->path.dlid = cpi->redirect_lid;
1441 target->path.pkey = cpi->redirect_pkey;
1442 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1443 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1444
1445 target->status = target->path.dlid ?
1446 SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1447 break;
1448
1449 case IB_CM_REJ_PORT_REDIRECT:
1450 if (srp_target_is_topspin(target)) {
1451 /*
1452 * Topspin/Cisco SRP gateways incorrectly send
1453 * reject reason code 25 when they mean 24
1454 * (port redirect).
1455 */
1456 memcpy(target->path.dgid.raw,
1457 event->param.rej_rcvd.ari, 16);
1458
1459 shost_printk(KERN_DEBUG, shost,
1460 PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1461 (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1462 (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1463
1464 target->status = SRP_PORT_REDIRECT;
1465 } else {
1466 shost_printk(KERN_WARNING, shost,
1467 " REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1468 target->status = -ECONNRESET;
1469 }
1470 break;
1471
1472 case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1473 shost_printk(KERN_WARNING, shost,
1474 " REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1475 target->status = -ECONNRESET;
1476 break;
1477
1478 case IB_CM_REJ_CONSUMER_DEFINED:
1479 opcode = *(u8 *) event->private_data;
1480 if (opcode == SRP_LOGIN_REJ) {
1481 struct srp_login_rej *rej = event->private_data;
1482 u32 reason = be32_to_cpu(rej->reason);
1483
1484 if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1485 shost_printk(KERN_WARNING, shost,
1486 PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1487 else
1488 shost_printk(KERN_WARNING, shost,
1489 PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1490 } else
1491 shost_printk(KERN_WARNING, shost,
1492 " REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1493 " opcode 0x%02x\n", opcode);
1494 target->status = -ECONNRESET;
1495 break;
1496
1497 case IB_CM_REJ_STALE_CONN:
1498 shost_printk(KERN_WARNING, shost, " REJ reason: stale connection\n");
1499 target->status = SRP_STALE_CONN;
1500 break;
1501
1502 default:
1503 shost_printk(KERN_WARNING, shost, " REJ reason 0x%x\n",
1504 event->param.rej_rcvd.reason);
1505 target->status = -ECONNRESET;
1506 }
1507 }
1508
1509 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1510 {
1511 struct srp_target_port *target = cm_id->context;
1512 int comp = 0;
1513
1514 switch (event->event) {
1515 case IB_CM_REQ_ERROR:
1516 shost_printk(KERN_DEBUG, target->scsi_host,
1517 PFX "Sending CM REQ failed\n");
1518 comp = 1;
1519 target->status = -ECONNRESET;
1520 break;
1521
1522 case IB_CM_REP_RECEIVED:
1523 comp = 1;
1524 srp_cm_rep_handler(cm_id, event->private_data, target);
1525 break;
1526
1527 case IB_CM_REJ_RECEIVED:
1528 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
1529 comp = 1;
1530
1531 srp_cm_rej_handler(cm_id, event, target);
1532 break;
1533
1534 case IB_CM_DREQ_RECEIVED:
1535 shost_printk(KERN_WARNING, target->scsi_host,
1536 PFX "DREQ received - connection closed\n");
1537 if (ib_send_cm_drep(cm_id, NULL, 0))
1538 shost_printk(KERN_ERR, target->scsi_host,
1539 PFX "Sending CM DREP failed\n");
1540 break;
1541
1542 case IB_CM_TIMEWAIT_EXIT:
1543 shost_printk(KERN_ERR, target->scsi_host,
1544 PFX "connection closed\n");
1545
1546 comp = 1;
1547 target->status = 0;
1548 break;
1549
1550 case IB_CM_MRA_RECEIVED:
1551 case IB_CM_DREQ_ERROR:
1552 case IB_CM_DREP_RECEIVED:
1553 break;
1554
1555 default:
1556 shost_printk(KERN_WARNING, target->scsi_host,
1557 PFX "Unhandled CM event %d\n", event->event);
1558 break;
1559 }
1560
1561 if (comp)
1562 complete(&target->done);
1563
1564 return 0;
1565 }
1566
1567 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1568 u64 req_tag, unsigned int lun, u8 func)
1569 {
1570 struct ib_device *dev = target->srp_host->srp_dev->dev;
1571 struct srp_iu *iu;
1572 struct srp_tsk_mgmt *tsk_mgmt;
1573
1574 if (target->state == SRP_TARGET_DEAD ||
1575 target->state == SRP_TARGET_REMOVED)
1576 return -1;
1577
1578 init_completion(&target->tsk_mgmt_done);
1579
1580 spin_lock_irq(&target->lock);
1581 iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
1582 spin_unlock_irq(&target->lock);
1583
1584 if (!iu)
1585 return -1;
1586
1587 ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
1588 DMA_TO_DEVICE);
1589 tsk_mgmt = iu->buf;
1590 memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1591
1592 tsk_mgmt->opcode = SRP_TSK_MGMT;
1593 tsk_mgmt->lun = cpu_to_be64((u64) lun << 48);
1594 tsk_mgmt->tag = req_tag | SRP_TAG_TSK_MGMT;
1595 tsk_mgmt->tsk_mgmt_func = func;
1596 tsk_mgmt->task_tag = req_tag;
1597
1598 ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
1599 DMA_TO_DEVICE);
1600 if (srp_post_send(target, iu, sizeof *tsk_mgmt)) {
1601 srp_put_tx_iu(target, iu, SRP_IU_TSK_MGMT);
1602 return -1;
1603 }
1604
1605 if (!wait_for_completion_timeout(&target->tsk_mgmt_done,
1606 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1607 return -1;
1608
1609 return 0;
1610 }
1611
1612 static int srp_abort(struct scsi_cmnd *scmnd)
1613 {
1614 struct srp_target_port *target = host_to_target(scmnd->device->host);
1615 struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
1616 int ret = SUCCESS;
1617
1618 shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
1619
1620 if (!req || target->qp_in_error)
1621 return FAILED;
1622 if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
1623 SRP_TSK_ABORT_TASK))
1624 return FAILED;
1625
1626 if (req->scmnd) {
1627 if (!target->tsk_mgmt_status) {
1628 srp_remove_req(target, req, 0);
1629 scmnd->result = DID_ABORT << 16;
1630 } else
1631 ret = FAILED;
1632 }
1633
1634 return ret;
1635 }
1636
1637 static int srp_reset_device(struct scsi_cmnd *scmnd)
1638 {
1639 struct srp_target_port *target = host_to_target(scmnd->device->host);
1640 int i;
1641
1642 shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
1643
1644 if (target->qp_in_error)
1645 return FAILED;
1646 if (srp_send_tsk_mgmt(target, SRP_TAG_NO_REQ, scmnd->device->lun,
1647 SRP_TSK_LUN_RESET))
1648 return FAILED;
1649 if (target->tsk_mgmt_status)
1650 return FAILED;
1651
1652 for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
1653 struct srp_request *req = &target->req_ring[i];
1654 if (req->scmnd && req->scmnd->device == scmnd->device)
1655 srp_reset_req(target, req);
1656 }
1657
1658 return SUCCESS;
1659 }
1660
1661 static int srp_reset_host(struct scsi_cmnd *scmnd)
1662 {
1663 struct srp_target_port *target = host_to_target(scmnd->device->host);
1664 int ret = FAILED;
1665
1666 shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
1667
1668 if (!srp_reconnect_target(target))
1669 ret = SUCCESS;
1670
1671 return ret;
1672 }
1673
1674 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
1675 char *buf)
1676 {
1677 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1678
1679 if (target->state == SRP_TARGET_DEAD ||
1680 target->state == SRP_TARGET_REMOVED)
1681 return -ENODEV;
1682
1683 return sprintf(buf, "0x%016llx\n",
1684 (unsigned long long) be64_to_cpu(target->id_ext));
1685 }
1686
1687 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
1688 char *buf)
1689 {
1690 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1691
1692 if (target->state == SRP_TARGET_DEAD ||
1693 target->state == SRP_TARGET_REMOVED)
1694 return -ENODEV;
1695
1696 return sprintf(buf, "0x%016llx\n",
1697 (unsigned long long) be64_to_cpu(target->ioc_guid));
1698 }
1699
1700 static ssize_t show_service_id(struct device *dev,
1701 struct device_attribute *attr, char *buf)
1702 {
1703 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1704
1705 if (target->state == SRP_TARGET_DEAD ||
1706 target->state == SRP_TARGET_REMOVED)
1707 return -ENODEV;
1708
1709 return sprintf(buf, "0x%016llx\n",
1710 (unsigned long long) be64_to_cpu(target->service_id));
1711 }
1712
1713 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
1714 char *buf)
1715 {
1716 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1717
1718 if (target->state == SRP_TARGET_DEAD ||
1719 target->state == SRP_TARGET_REMOVED)
1720 return -ENODEV;
1721
1722 return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1723 }
1724
1725 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
1726 char *buf)
1727 {
1728 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1729
1730 if (target->state == SRP_TARGET_DEAD ||
1731 target->state == SRP_TARGET_REMOVED)
1732 return -ENODEV;
1733
1734 return sprintf(buf, "%pI6\n", target->path.dgid.raw);
1735 }
1736
1737 static ssize_t show_orig_dgid(struct device *dev,
1738 struct device_attribute *attr, char *buf)
1739 {
1740 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1741
1742 if (target->state == SRP_TARGET_DEAD ||
1743 target->state == SRP_TARGET_REMOVED)
1744 return -ENODEV;
1745
1746 return sprintf(buf, "%pI6\n", target->orig_dgid);
1747 }
1748
1749 static ssize_t show_req_lim(struct device *dev,
1750 struct device_attribute *attr, char *buf)
1751 {
1752 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1753
1754 if (target->state == SRP_TARGET_DEAD ||
1755 target->state == SRP_TARGET_REMOVED)
1756 return -ENODEV;
1757
1758 return sprintf(buf, "%d\n", target->req_lim);
1759 }
1760
1761 static ssize_t show_zero_req_lim(struct device *dev,
1762 struct device_attribute *attr, char *buf)
1763 {
1764 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1765
1766 if (target->state == SRP_TARGET_DEAD ||
1767 target->state == SRP_TARGET_REMOVED)
1768 return -ENODEV;
1769
1770 return sprintf(buf, "%d\n", target->zero_req_lim);
1771 }
1772
1773 static ssize_t show_local_ib_port(struct device *dev,
1774 struct device_attribute *attr, char *buf)
1775 {
1776 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1777
1778 return sprintf(buf, "%d\n", target->srp_host->port);
1779 }
1780
1781 static ssize_t show_local_ib_device(struct device *dev,
1782 struct device_attribute *attr, char *buf)
1783 {
1784 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1785
1786 return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
1787 }
1788
1789 static ssize_t show_cmd_sg_entries(struct device *dev,
1790 struct device_attribute *attr, char *buf)
1791 {
1792 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1793
1794 return sprintf(buf, "%u\n", target->cmd_sg_cnt);
1795 }
1796
1797 static ssize_t show_allow_ext_sg(struct device *dev,
1798 struct device_attribute *attr, char *buf)
1799 {
1800 struct srp_target_port *target = host_to_target(class_to_shost(dev));
1801
1802 return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
1803 }
1804
1805 static DEVICE_ATTR(id_ext, S_IRUGO, show_id_ext, NULL);
1806 static DEVICE_ATTR(ioc_guid, S_IRUGO, show_ioc_guid, NULL);
1807 static DEVICE_ATTR(service_id, S_IRUGO, show_service_id, NULL);
1808 static DEVICE_ATTR(pkey, S_IRUGO, show_pkey, NULL);
1809 static DEVICE_ATTR(dgid, S_IRUGO, show_dgid, NULL);
1810 static DEVICE_ATTR(orig_dgid, S_IRUGO, show_orig_dgid, NULL);
1811 static DEVICE_ATTR(req_lim, S_IRUGO, show_req_lim, NULL);
1812 static DEVICE_ATTR(zero_req_lim, S_IRUGO, show_zero_req_lim, NULL);
1813 static DEVICE_ATTR(local_ib_port, S_IRUGO, show_local_ib_port, NULL);
1814 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1815 static DEVICE_ATTR(cmd_sg_entries, S_IRUGO, show_cmd_sg_entries, NULL);
1816 static DEVICE_ATTR(allow_ext_sg, S_IRUGO, show_allow_ext_sg, NULL);
1817
1818 static struct device_attribute *srp_host_attrs[] = {
1819 &dev_attr_id_ext,
1820 &dev_attr_ioc_guid,
1821 &dev_attr_service_id,
1822 &dev_attr_pkey,
1823 &dev_attr_dgid,
1824 &dev_attr_orig_dgid,
1825 &dev_attr_req_lim,
1826 &dev_attr_zero_req_lim,
1827 &dev_attr_local_ib_port,
1828 &dev_attr_local_ib_device,
1829 &dev_attr_cmd_sg_entries,
1830 &dev_attr_allow_ext_sg,
1831 NULL
1832 };
1833
1834 static struct scsi_host_template srp_template = {
1835 .module = THIS_MODULE,
1836 .name = "InfiniBand SRP initiator",
1837 .proc_name = DRV_NAME,
1838 .info = srp_target_info,
1839 .queuecommand = srp_queuecommand,
1840 .eh_abort_handler = srp_abort,
1841 .eh_device_reset_handler = srp_reset_device,
1842 .eh_host_reset_handler = srp_reset_host,
1843 .sg_tablesize = SRP_DEF_SG_TABLESIZE,
1844 .can_queue = SRP_CMD_SQ_SIZE,
1845 .this_id = -1,
1846 .cmd_per_lun = SRP_CMD_SQ_SIZE,
1847 .use_clustering = ENABLE_CLUSTERING,
1848 .shost_attrs = srp_host_attrs
1849 };
1850
1851 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1852 {
1853 struct srp_rport_identifiers ids;
1854 struct srp_rport *rport;
1855
1856 sprintf(target->target_name, "SRP.T10:%016llX",
1857 (unsigned long long) be64_to_cpu(target->id_ext));
1858
1859 if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
1860 return -ENODEV;
1861
1862 memcpy(ids.port_id, &target->id_ext, 8);
1863 memcpy(ids.port_id + 8, &target->ioc_guid, 8);
1864 ids.roles = SRP_RPORT_ROLE_TARGET;
1865 rport = srp_rport_add(target->scsi_host, &ids);
1866 if (IS_ERR(rport)) {
1867 scsi_remove_host(target->scsi_host);
1868 return PTR_ERR(rport);
1869 }
1870
1871 spin_lock(&host->target_lock);
1872 list_add_tail(&target->list, &host->target_list);
1873 spin_unlock(&host->target_lock);
1874
1875 target->state = SRP_TARGET_LIVE;
1876
1877 scsi_scan_target(&target->scsi_host->shost_gendev,
1878 0, target->scsi_id, SCAN_WILD_CARD, 0);
1879
1880 return 0;
1881 }
1882
1883 static void srp_release_dev(struct device *dev)
1884 {
1885 struct srp_host *host =
1886 container_of(dev, struct srp_host, dev);
1887
1888 complete(&host->released);
1889 }
1890
1891 static struct class srp_class = {
1892 .name = "infiniband_srp",
1893 .dev_release = srp_release_dev
1894 };
1895
1896 /*
1897 * Target ports are added by writing
1898 *
1899 * id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1900 * pkey=<P_Key>,service_id=<service ID>
1901 *
1902 * to the add_target sysfs attribute.
1903 */
1904 enum {
1905 SRP_OPT_ERR = 0,
1906 SRP_OPT_ID_EXT = 1 << 0,
1907 SRP_OPT_IOC_GUID = 1 << 1,
1908 SRP_OPT_DGID = 1 << 2,
1909 SRP_OPT_PKEY = 1 << 3,
1910 SRP_OPT_SERVICE_ID = 1 << 4,
1911 SRP_OPT_MAX_SECT = 1 << 5,
1912 SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
1913 SRP_OPT_IO_CLASS = 1 << 7,
1914 SRP_OPT_INITIATOR_EXT = 1 << 8,
1915 SRP_OPT_CMD_SG_ENTRIES = 1 << 9,
1916 SRP_OPT_ALLOW_EXT_SG = 1 << 10,
1917 SRP_OPT_SG_TABLESIZE = 1 << 11,
1918 SRP_OPT_ALL = (SRP_OPT_ID_EXT |
1919 SRP_OPT_IOC_GUID |
1920 SRP_OPT_DGID |
1921 SRP_OPT_PKEY |
1922 SRP_OPT_SERVICE_ID),
1923 };
1924
1925 static const match_table_t srp_opt_tokens = {
1926 { SRP_OPT_ID_EXT, "id_ext=%s" },
1927 { SRP_OPT_IOC_GUID, "ioc_guid=%s" },
1928 { SRP_OPT_DGID, "dgid=%s" },
1929 { SRP_OPT_PKEY, "pkey=%x" },
1930 { SRP_OPT_SERVICE_ID, "service_id=%s" },
1931 { SRP_OPT_MAX_SECT, "max_sect=%d" },
1932 { SRP_OPT_MAX_CMD_PER_LUN, "max_cmd_per_lun=%d" },
1933 { SRP_OPT_IO_CLASS, "io_class=%x" },
1934 { SRP_OPT_INITIATOR_EXT, "initiator_ext=%s" },
1935 { SRP_OPT_CMD_SG_ENTRIES, "cmd_sg_entries=%u" },
1936 { SRP_OPT_ALLOW_EXT_SG, "allow_ext_sg=%u" },
1937 { SRP_OPT_SG_TABLESIZE, "sg_tablesize=%u" },
1938 { SRP_OPT_ERR, NULL }
1939 };
1940
1941 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1942 {
1943 char *options, *sep_opt;
1944 char *p;
1945 char dgid[3];
1946 substring_t args[MAX_OPT_ARGS];
1947 int opt_mask = 0;
1948 int token;
1949 int ret = -EINVAL;
1950 int i;
1951
1952 options = kstrdup(buf, GFP_KERNEL);
1953 if (!options)
1954 return -ENOMEM;
1955
1956 sep_opt = options;
1957 while ((p = strsep(&sep_opt, ",")) != NULL) {
1958 if (!*p)
1959 continue;
1960
1961 token = match_token(p, srp_opt_tokens, args);
1962 opt_mask |= token;
1963
1964 switch (token) {
1965 case SRP_OPT_ID_EXT:
1966 p = match_strdup(args);
1967 if (!p) {
1968 ret = -ENOMEM;
1969 goto out;
1970 }
1971 target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1972 kfree(p);
1973 break;
1974
1975 case SRP_OPT_IOC_GUID:
1976 p = match_strdup(args);
1977 if (!p) {
1978 ret = -ENOMEM;
1979 goto out;
1980 }
1981 target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1982 kfree(p);
1983 break;
1984
1985 case SRP_OPT_DGID:
1986 p = match_strdup(args);
1987 if (!p) {
1988 ret = -ENOMEM;
1989 goto out;
1990 }
1991 if (strlen(p) != 32) {
1992 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1993 kfree(p);
1994 goto out;
1995 }
1996
1997 for (i = 0; i < 16; ++i) {
1998 strlcpy(dgid, p + i * 2, 3);
1999 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
2000 }
2001 kfree(p);
2002 memcpy(target->orig_dgid, target->path.dgid.raw, 16);
2003 break;
2004
2005 case SRP_OPT_PKEY:
2006 if (match_hex(args, &token)) {
2007 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
2008 goto out;
2009 }
2010 target->path.pkey = cpu_to_be16(token);
2011 break;
2012
2013 case SRP_OPT_SERVICE_ID:
2014 p = match_strdup(args);
2015 if (!p) {
2016 ret = -ENOMEM;
2017 goto out;
2018 }
2019 target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
2020 target->path.service_id = target->service_id;
2021 kfree(p);
2022 break;
2023
2024 case SRP_OPT_MAX_SECT:
2025 if (match_int(args, &token)) {
2026 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
2027 goto out;
2028 }
2029 target->scsi_host->max_sectors = token;
2030 break;
2031
2032 case SRP_OPT_MAX_CMD_PER_LUN:
2033 if (match_int(args, &token)) {
2034 printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
2035 goto out;
2036 }
2037 target->scsi_host->cmd_per_lun = min(token, SRP_CMD_SQ_SIZE);
2038 break;
2039
2040 case SRP_OPT_IO_CLASS:
2041 if (match_hex(args, &token)) {
2042 printk(KERN_WARNING PFX "bad IO class parameter '%s' \n", p);
2043 goto out;
2044 }
2045 if (token != SRP_REV10_IB_IO_CLASS &&
2046 token != SRP_REV16A_IB_IO_CLASS) {
2047 printk(KERN_WARNING PFX "unknown IO class parameter value"
2048 " %x specified (use %x or %x).\n",
2049 token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
2050 goto out;
2051 }
2052 target->io_class = token;
2053 break;
2054
2055 case SRP_OPT_INITIATOR_EXT:
2056 p = match_strdup(args);
2057 if (!p) {
2058 ret = -ENOMEM;
2059 goto out;
2060 }
2061 target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
2062 kfree(p);
2063 break;
2064
2065 case SRP_OPT_CMD_SG_ENTRIES:
2066 if (match_int(args, &token) || token < 1 || token > 255) {
2067 printk(KERN_WARNING PFX "bad max cmd_sg_entries parameter '%s'\n", p);
2068 goto out;
2069 }
2070 target->cmd_sg_cnt = token;
2071 break;
2072
2073 case SRP_OPT_ALLOW_EXT_SG:
2074 if (match_int(args, &token)) {
2075 printk(KERN_WARNING PFX "bad allow_ext_sg parameter '%s'\n", p);
2076 goto out;
2077 }
2078 target->allow_ext_sg = !!token;
2079 break;
2080
2081 case SRP_OPT_SG_TABLESIZE:
2082 if (match_int(args, &token) || token < 1 ||
2083 token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
2084 printk(KERN_WARNING PFX "bad max sg_tablesize parameter '%s'\n", p);
2085 goto out;
2086 }
2087 target->sg_tablesize = token;
2088 break;
2089
2090 default:
2091 printk(KERN_WARNING PFX "unknown parameter or missing value "
2092 "'%s' in target creation request\n", p);
2093 goto out;
2094 }
2095 }
2096
2097 if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
2098 ret = 0;
2099 else
2100 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
2101 if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
2102 !(srp_opt_tokens[i].token & opt_mask))
2103 printk(KERN_WARNING PFX "target creation request is "
2104 "missing parameter '%s'\n",
2105 srp_opt_tokens[i].pattern);
2106
2107 out:
2108 kfree(options);
2109 return ret;
2110 }
2111
2112 static ssize_t srp_create_target(struct device *dev,
2113 struct device_attribute *attr,
2114 const char *buf, size_t count)
2115 {
2116 struct srp_host *host =
2117 container_of(dev, struct srp_host, dev);
2118 struct Scsi_Host *target_host;
2119 struct srp_target_port *target;
2120 struct ib_device *ibdev = host->srp_dev->dev;
2121 dma_addr_t dma_addr;
2122 int i, ret;
2123
2124 target_host = scsi_host_alloc(&srp_template,
2125 sizeof (struct srp_target_port));
2126 if (!target_host)
2127 return -ENOMEM;
2128
2129 target_host->transportt = ib_srp_transport_template;
2130 target_host->max_channel = 0;
2131 target_host->max_id = 1;
2132 target_host->max_lun = SRP_MAX_LUN;
2133 target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
2134
2135 target = host_to_target(target_host);
2136
2137 target->io_class = SRP_REV16A_IB_IO_CLASS;
2138 target->scsi_host = target_host;
2139 target->srp_host = host;
2140 target->lkey = host->srp_dev->mr->lkey;
2141 target->rkey = host->srp_dev->mr->rkey;
2142 target->cmd_sg_cnt = cmd_sg_entries;
2143 target->sg_tablesize = indirect_sg_entries ? : cmd_sg_entries;
2144 target->allow_ext_sg = allow_ext_sg;
2145
2146 ret = srp_parse_options(buf, target);
2147 if (ret)
2148 goto err;
2149
2150 if (!host->srp_dev->fmr_pool && !target->allow_ext_sg &&
2151 target->cmd_sg_cnt < target->sg_tablesize) {
2152 printk(KERN_WARNING PFX "No FMR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
2153 target->sg_tablesize = target->cmd_sg_cnt;
2154 }
2155
2156 target_host->sg_tablesize = target->sg_tablesize;
2157 target->indirect_size = target->sg_tablesize *
2158 sizeof (struct srp_direct_buf);
2159 target->max_iu_len = sizeof (struct srp_cmd) +
2160 sizeof (struct srp_indirect_buf) +
2161 target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
2162
2163 spin_lock_init(&target->lock);
2164 INIT_LIST_HEAD(&target->free_tx);
2165 INIT_LIST_HEAD(&target->free_reqs);
2166 for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
2167 struct srp_request *req = &target->req_ring[i];
2168
2169 req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof (void *),
2170 GFP_KERNEL);
2171 req->map_page = kmalloc(SRP_FMR_SIZE * sizeof (void *),
2172 GFP_KERNEL);
2173 req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
2174 if (!req->fmr_list || !req->map_page || !req->indirect_desc)
2175 goto err_free_mem;
2176
2177 dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
2178 target->indirect_size,
2179 DMA_TO_DEVICE);
2180 if (ib_dma_mapping_error(ibdev, dma_addr))
2181 goto err_free_mem;
2182
2183 req->indirect_dma_addr = dma_addr;
2184 req->index = i;
2185 list_add_tail(&req->list, &target->free_reqs);
2186 }
2187
2188 ib_query_gid(ibdev, host->port, 0, &target->path.sgid);
2189
2190 shost_printk(KERN_DEBUG, target->scsi_host, PFX
2191 "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
2192 "service_id %016llx dgid %pI6\n",
2193 (unsigned long long) be64_to_cpu(target->id_ext),
2194 (unsigned long long) be64_to_cpu(target->ioc_guid),
2195 be16_to_cpu(target->path.pkey),
2196 (unsigned long long) be64_to_cpu(target->service_id),
2197 target->path.dgid.raw);
2198
2199 ret = srp_create_target_ib(target);
2200 if (ret)
2201 goto err_free_mem;
2202
2203 ret = srp_new_cm_id(target);
2204 if (ret)
2205 goto err_free_ib;
2206
2207 target->qp_in_error = 0;
2208 ret = srp_connect_target(target);
2209 if (ret) {
2210 shost_printk(KERN_ERR, target->scsi_host,
2211 PFX "Connection failed\n");
2212 goto err_cm_id;
2213 }
2214
2215 ret = srp_add_target(host, target);
2216 if (ret)
2217 goto err_disconnect;
2218
2219 return count;
2220
2221 err_disconnect:
2222 srp_disconnect_target(target);
2223
2224 err_cm_id:
2225 ib_destroy_cm_id(target->cm_id);
2226
2227 err_free_ib:
2228 srp_free_target_ib(target);
2229
2230 err_free_mem:
2231 srp_free_req_data(target);
2232
2233 err:
2234 scsi_host_put(target_host);
2235
2236 return ret;
2237 }
2238
2239 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
2240
2241 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
2242 char *buf)
2243 {
2244 struct srp_host *host = container_of(dev, struct srp_host, dev);
2245
2246 return sprintf(buf, "%s\n", host->srp_dev->dev->name);
2247 }
2248
2249 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
2250
2251 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
2252 char *buf)
2253 {
2254 struct srp_host *host = container_of(dev, struct srp_host, dev);
2255
2256 return sprintf(buf, "%d\n", host->port);
2257 }
2258
2259 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
2260
2261 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
2262 {
2263 struct srp_host *host;
2264
2265 host = kzalloc(sizeof *host, GFP_KERNEL);
2266 if (!host)
2267 return NULL;
2268
2269 INIT_LIST_HEAD(&host->target_list);
2270 spin_lock_init(&host->target_lock);
2271 init_completion(&host->released);
2272 host->srp_dev = device;
2273 host->port = port;
2274
2275 host->dev.class = &srp_class;
2276 host->dev.parent = device->dev->dma_device;
2277 dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
2278
2279 if (device_register(&host->dev))
2280 goto free_host;
2281 if (device_create_file(&host->dev, &dev_attr_add_target))
2282 goto err_class;
2283 if (device_create_file(&host->dev, &dev_attr_ibdev))
2284 goto err_class;
2285 if (device_create_file(&host->dev, &dev_attr_port))
2286 goto err_class;
2287
2288 return host;
2289
2290 err_class:
2291 device_unregister(&host->dev);
2292
2293 free_host:
2294 kfree(host);
2295
2296 return NULL;
2297 }
2298
2299 static void srp_add_one(struct ib_device *device)
2300 {
2301 struct srp_device *srp_dev;
2302 struct ib_device_attr *dev_attr;
2303 struct ib_fmr_pool_param fmr_param;
2304 struct srp_host *host;
2305 int max_pages_per_fmr, fmr_page_shift, s, e, p;
2306
2307 dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
2308 if (!dev_attr)
2309 return;
2310
2311 if (ib_query_device(device, dev_attr)) {
2312 printk(KERN_WARNING PFX "Query device failed for %s\n",
2313 device->name);
2314 goto free_attr;
2315 }
2316
2317 srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
2318 if (!srp_dev)
2319 goto free_attr;
2320
2321 /*
2322 * Use the smallest page size supported by the HCA, down to a
2323 * minimum of 4096 bytes. We're unlikely to build large sglists
2324 * out of smaller entries.
2325 */
2326 fmr_page_shift = max(12, ffs(dev_attr->page_size_cap) - 1);
2327 srp_dev->fmr_page_size = 1 << fmr_page_shift;
2328 srp_dev->fmr_page_mask = ~((u64) srp_dev->fmr_page_size - 1);
2329 srp_dev->fmr_max_size = srp_dev->fmr_page_size * SRP_FMR_SIZE;
2330
2331 INIT_LIST_HEAD(&srp_dev->dev_list);
2332
2333 srp_dev->dev = device;
2334 srp_dev->pd = ib_alloc_pd(device);
2335 if (IS_ERR(srp_dev->pd))
2336 goto free_dev;
2337
2338 srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
2339 IB_ACCESS_LOCAL_WRITE |
2340 IB_ACCESS_REMOTE_READ |
2341 IB_ACCESS_REMOTE_WRITE);
2342 if (IS_ERR(srp_dev->mr))
2343 goto err_pd;
2344
2345 for (max_pages_per_fmr = SRP_FMR_SIZE;
2346 max_pages_per_fmr >= SRP_FMR_MIN_SIZE;
2347 max_pages_per_fmr /= 2, srp_dev->fmr_max_size /= 2) {
2348 memset(&fmr_param, 0, sizeof fmr_param);
2349 fmr_param.pool_size = SRP_FMR_POOL_SIZE;
2350 fmr_param.dirty_watermark = SRP_FMR_DIRTY_SIZE;
2351 fmr_param.cache = 1;
2352 fmr_param.max_pages_per_fmr = max_pages_per_fmr;
2353 fmr_param.page_shift = fmr_page_shift;
2354 fmr_param.access = (IB_ACCESS_LOCAL_WRITE |
2355 IB_ACCESS_REMOTE_WRITE |
2356 IB_ACCESS_REMOTE_READ);
2357
2358 srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
2359 if (!IS_ERR(srp_dev->fmr_pool))
2360 break;
2361 }
2362
2363 if (IS_ERR(srp_dev->fmr_pool))
2364 srp_dev->fmr_pool = NULL;
2365
2366 if (device->node_type == RDMA_NODE_IB_SWITCH) {
2367 s = 0;
2368 e = 0;
2369 } else {
2370 s = 1;
2371 e = device->phys_port_cnt;
2372 }
2373
2374 for (p = s; p <= e; ++p) {
2375 host = srp_add_port(srp_dev, p);
2376 if (host)
2377 list_add_tail(&host->list, &srp_dev->dev_list);
2378 }
2379
2380 ib_set_client_data(device, &srp_client, srp_dev);
2381
2382 goto free_attr;
2383
2384 err_pd:
2385 ib_dealloc_pd(srp_dev->pd);
2386
2387 free_dev:
2388 kfree(srp_dev);
2389
2390 free_attr:
2391 kfree(dev_attr);
2392 }
2393
2394 static void srp_remove_one(struct ib_device *device)
2395 {
2396 struct srp_device *srp_dev;
2397 struct srp_host *host, *tmp_host;
2398 LIST_HEAD(target_list);
2399 struct srp_target_port *target, *tmp_target;
2400
2401 srp_dev = ib_get_client_data(device, &srp_client);
2402
2403 list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2404 device_unregister(&host->dev);
2405 /*
2406 * Wait for the sysfs entry to go away, so that no new
2407 * target ports can be created.
2408 */
2409 wait_for_completion(&host->released);
2410
2411 /*
2412 * Mark all target ports as removed, so we stop queueing
2413 * commands and don't try to reconnect.
2414 */
2415 spin_lock(&host->target_lock);
2416 list_for_each_entry(target, &host->target_list, list) {
2417 spin_lock_irq(&target->lock);
2418 target->state = SRP_TARGET_REMOVED;
2419 spin_unlock_irq(&target->lock);
2420 }
2421 spin_unlock(&host->target_lock);
2422
2423 /*
2424 * Wait for any reconnection tasks that may have
2425 * started before we marked our target ports as
2426 * removed, and any target port removal tasks.
2427 */
2428 flush_workqueue(ib_wq);
2429
2430 list_for_each_entry_safe(target, tmp_target,
2431 &host->target_list, list) {
2432 srp_remove_host(target->scsi_host);
2433 scsi_remove_host(target->scsi_host);
2434 srp_disconnect_target(target);
2435 ib_destroy_cm_id(target->cm_id);
2436 srp_free_target_ib(target);
2437 srp_free_req_data(target);
2438 scsi_host_put(target->scsi_host);
2439 }
2440
2441 kfree(host);
2442 }
2443
2444 if (srp_dev->fmr_pool)
2445 ib_destroy_fmr_pool(srp_dev->fmr_pool);
2446 ib_dereg_mr(srp_dev->mr);
2447 ib_dealloc_pd(srp_dev->pd);
2448
2449 kfree(srp_dev);
2450 }
2451
2452 static struct srp_function_template ib_srp_transport_functions = {
2453 };
2454
2455 static int __init srp_init_module(void)
2456 {
2457 int ret;
2458
2459 BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
2460
2461 if (srp_sg_tablesize) {
2462 printk(KERN_WARNING PFX "srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
2463 if (!cmd_sg_entries)
2464 cmd_sg_entries = srp_sg_tablesize;
2465 }
2466
2467 if (!cmd_sg_entries)
2468 cmd_sg_entries = SRP_DEF_SG_TABLESIZE;
2469
2470 if (cmd_sg_entries > 255) {
2471 printk(KERN_WARNING PFX "Clamping cmd_sg_entries to 255\n");
2472 cmd_sg_entries = 255;
2473 }
2474
2475 if (!indirect_sg_entries)
2476 indirect_sg_entries = cmd_sg_entries;
2477 else if (indirect_sg_entries < cmd_sg_entries) {
2478 printk(KERN_WARNING PFX "Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n", cmd_sg_entries);
2479 indirect_sg_entries = cmd_sg_entries;
2480 }
2481
2482 ib_srp_transport_template =
2483 srp_attach_transport(&ib_srp_transport_functions);
2484 if (!ib_srp_transport_template)
2485 return -ENOMEM;
2486
2487 ret = class_register(&srp_class);
2488 if (ret) {
2489 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
2490 srp_release_transport(ib_srp_transport_template);
2491 return ret;
2492 }
2493
2494 ib_sa_register_client(&srp_sa_client);
2495
2496 ret = ib_register_client(&srp_client);
2497 if (ret) {
2498 printk(KERN_ERR PFX "couldn't register IB client\n");
2499 srp_release_transport(ib_srp_transport_template);
2500 ib_sa_unregister_client(&srp_sa_client);
2501 class_unregister(&srp_class);
2502 return ret;
2503 }
2504
2505 return 0;
2506 }
2507
2508 static void __exit srp_cleanup_module(void)
2509 {
2510 ib_unregister_client(&srp_client);
2511 ib_sa_unregister_client(&srp_sa_client);
2512 class_unregister(&srp_class);
2513 srp_release_transport(ib_srp_transport_template);
2514 }
2515
2516 module_init(srp_init_module);
2517 module_exit(srp_cleanup_module);