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Linux 4.2.1
[linux/fpc-iii.git] / drivers / infiniband / ulp / srp / ib_srp.c
blob31a20b462266611299aeeae5cd51fd19b69b635e
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/slab.h>
38 #include <linux/err.h>
39 #include <linux/string.h>
40 #include <linux/parser.h>
41 #include <linux/random.h>
42 #include <linux/jiffies.h>
43 #include <rdma/ib_cache.h>
44
45 #include <linux/atomic.h>
46
47 #include <scsi/scsi.h>
48 #include <scsi/scsi_device.h>
49 #include <scsi/scsi_dbg.h>
50 #include <scsi/scsi_tcq.h>
51 #include <scsi/srp.h>
52 #include <scsi/scsi_transport_srp.h>
53
54 #include "ib_srp.h"
55
56 #define DRV_NAME "ib_srp"
57 #define PFX DRV_NAME ": "
58 #define DRV_VERSION "1.0"
59 #define DRV_RELDATE "July 1, 2013"
60
61 MODULE_AUTHOR("Roland Dreier");
62 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator");
63 MODULE_LICENSE("Dual BSD/GPL");
64 MODULE_VERSION(DRV_VERSION);
65 MODULE_INFO(release_date, DRV_RELDATE);
66
67 static unsigned int srp_sg_tablesize;
68 static unsigned int cmd_sg_entries;
69 static unsigned int indirect_sg_entries;
70 static bool allow_ext_sg;
71 static bool prefer_fr;
72 static bool register_always;
73 static int topspin_workarounds = 1;
74
75 module_param(srp_sg_tablesize, uint, 0444);
76 MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
77
78 module_param(cmd_sg_entries, uint, 0444);
79 MODULE_PARM_DESC(cmd_sg_entries,
80 "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
81
82 module_param(indirect_sg_entries, uint, 0444);
83 MODULE_PARM_DESC(indirect_sg_entries,
84 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");
85
86 module_param(allow_ext_sg, bool, 0444);
87 MODULE_PARM_DESC(allow_ext_sg,
88 "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");
89
90 module_param(topspin_workarounds, int, 0444);
91 MODULE_PARM_DESC(topspin_workarounds,
92 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
93
94 module_param(prefer_fr, bool, 0444);
95 MODULE_PARM_DESC(prefer_fr,
96 "Whether to use fast registration if both FMR and fast registration are supported");
97
98 module_param(register_always, bool, 0444);
99 MODULE_PARM_DESC(register_always,
100 "Use memory registration even for contiguous memory regions");
101
102 static const struct kernel_param_ops srp_tmo_ops;
103
104 static int srp_reconnect_delay = 10;
105 module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
106 S_IRUGO | S_IWUSR);
107 MODULE_PARM_DESC(reconnect_delay, "Time between successive reconnect attempts");
108
109 static int srp_fast_io_fail_tmo = 15;
110 module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
111 S_IRUGO | S_IWUSR);
112 MODULE_PARM_DESC(fast_io_fail_tmo,
113 "Number of seconds between the observation of a transport"
114 " layer error and failing all I/O. \"off\" means that this"
115 " functionality is disabled.");
116
117 static int srp_dev_loss_tmo = 600;
118 module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
119 S_IRUGO | S_IWUSR);
120 MODULE_PARM_DESC(dev_loss_tmo,
121 "Maximum number of seconds that the SRP transport should"
122 " insulate transport layer errors. After this time has been"
123 " exceeded the SCSI host is removed. Should be"
124 " between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
125 " if fast_io_fail_tmo has not been set. \"off\" means that"
126 " this functionality is disabled.");
127
128 static unsigned ch_count;
129 module_param(ch_count, uint, 0444);
130 MODULE_PARM_DESC(ch_count,
131 "Number of RDMA channels to use for communication with an SRP target. Using more than one channel improves performance if the HCA supports multiple completion vectors. The default value is the minimum of four times the number of online CPU sockets and the number of completion vectors supported by the HCA.");
132
133 static void srp_add_one(struct ib_device *device);
134 static void srp_remove_one(struct ib_device *device);
135 static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr);
136 static void srp_send_completion(struct ib_cq *cq, void *ch_ptr);
137 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
138
139 static struct scsi_transport_template *ib_srp_transport_template;
140 static struct workqueue_struct *srp_remove_wq;
141
142 static struct ib_client srp_client = {
143 .name = "srp",
144 .add = srp_add_one,
145 .remove = srp_remove_one
146 };
147
148 static struct ib_sa_client srp_sa_client;
149
150 static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
151 {
152 int tmo = *(int *)kp->arg;
153
154 if (tmo >= 0)
155 return sprintf(buffer, "%d", tmo);
156 else
157 return sprintf(buffer, "off");
158 }
159
160 static int srp_tmo_set(const char *val, const struct kernel_param *kp)
161 {
162 int tmo, res;
163
164 res = srp_parse_tmo(&tmo, val);
165 if (res)
166 goto out;
167
168 if (kp->arg == &srp_reconnect_delay)
169 res = srp_tmo_valid(tmo, srp_fast_io_fail_tmo,
170 srp_dev_loss_tmo);
171 else if (kp->arg == &srp_fast_io_fail_tmo)
172 res = srp_tmo_valid(srp_reconnect_delay, tmo, srp_dev_loss_tmo);
173 else
174 res = srp_tmo_valid(srp_reconnect_delay, srp_fast_io_fail_tmo,
175 tmo);
176 if (res)
177 goto out;
178 *(int *)kp->arg = tmo;
179
180 out:
181 return res;
182 }
183
184 static const struct kernel_param_ops srp_tmo_ops = {
185 .get = srp_tmo_get,
186 .set = srp_tmo_set,
187 };
188
189 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
190 {
191 return (struct srp_target_port *) host->hostdata;
192 }
193
194 static const char *srp_target_info(struct Scsi_Host *host)
195 {
196 return host_to_target(host)->target_name;
197 }
198
199 static int srp_target_is_topspin(struct srp_target_port *target)
200 {
201 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
202 static const u8 cisco_oui[3] = { 0x00, 0x1b, 0x0d };
203
204 return topspin_workarounds &&
205 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
206 !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
207 }
208
209 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
210 gfp_t gfp_mask,
211 enum dma_data_direction direction)
212 {
213 struct srp_iu *iu;
214
215 iu = kmalloc(sizeof *iu, gfp_mask);
216 if (!iu)
217 goto out;
218
219 iu->buf = kzalloc(size, gfp_mask);
220 if (!iu->buf)
221 goto out_free_iu;
222
223 iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
224 direction);
225 if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
226 goto out_free_buf;
227
228 iu->size = size;
229 iu->direction = direction;
230
231 return iu;
232
233 out_free_buf:
234 kfree(iu->buf);
235 out_free_iu:
236 kfree(iu);
237 out:
238 return NULL;
239 }
240
241 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
242 {
243 if (!iu)
244 return;
245
246 ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
247 iu->direction);
248 kfree(iu->buf);
249 kfree(iu);
250 }
251
252 static void srp_qp_event(struct ib_event *event, void *context)
253 {
254 pr_debug("QP event %s (%d)\n",
255 ib_event_msg(event->event), event->event);
256 }
257
258 static int srp_init_qp(struct srp_target_port *target,
259 struct ib_qp *qp)
260 {
261 struct ib_qp_attr *attr;
262 int ret;
263
264 attr = kmalloc(sizeof *attr, GFP_KERNEL);
265 if (!attr)
266 return -ENOMEM;
267
268 ret = ib_find_cached_pkey(target->srp_host->srp_dev->dev,
269 target->srp_host->port,
270 be16_to_cpu(target->pkey),
271 &attr->pkey_index);
272 if (ret)
273 goto out;
274
275 attr->qp_state = IB_QPS_INIT;
276 attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
277 IB_ACCESS_REMOTE_WRITE);
278 attr->port_num = target->srp_host->port;
279
280 ret = ib_modify_qp(qp, attr,
281 IB_QP_STATE |
282 IB_QP_PKEY_INDEX |
283 IB_QP_ACCESS_FLAGS |
284 IB_QP_PORT);
285
286 out:
287 kfree(attr);
288 return ret;
289 }
290
291 static int srp_new_cm_id(struct srp_rdma_ch *ch)
292 {
293 struct srp_target_port *target = ch->target;
294 struct ib_cm_id *new_cm_id;
295
296 new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
297 srp_cm_handler, ch);
298 if (IS_ERR(new_cm_id))
299 return PTR_ERR(new_cm_id);
300
301 if (ch->cm_id)
302 ib_destroy_cm_id(ch->cm_id);
303 ch->cm_id = new_cm_id;
304 ch->path.sgid = target->sgid;
305 ch->path.dgid = target->orig_dgid;
306 ch->path.pkey = target->pkey;
307 ch->path.service_id = target->service_id;
308
309 return 0;
310 }
311
312 static struct ib_fmr_pool *srp_alloc_fmr_pool(struct srp_target_port *target)
313 {
314 struct srp_device *dev = target->srp_host->srp_dev;
315 struct ib_fmr_pool_param fmr_param;
316
317 memset(&fmr_param, 0, sizeof(fmr_param));
318 fmr_param.pool_size = target->scsi_host->can_queue;
319 fmr_param.dirty_watermark = fmr_param.pool_size / 4;
320 fmr_param.cache = 1;
321 fmr_param.max_pages_per_fmr = dev->max_pages_per_mr;
322 fmr_param.page_shift = ilog2(dev->mr_page_size);
323 fmr_param.access = (IB_ACCESS_LOCAL_WRITE |
324 IB_ACCESS_REMOTE_WRITE |
325 IB_ACCESS_REMOTE_READ);
326
327 return ib_create_fmr_pool(dev->pd, &fmr_param);
328 }
329
330 /**
331 * srp_destroy_fr_pool() - free the resources owned by a pool
332 * @pool: Fast registration pool to be destroyed.
333 */
334 static void srp_destroy_fr_pool(struct srp_fr_pool *pool)
335 {
336 int i;
337 struct srp_fr_desc *d;
338
339 if (!pool)
340 return;
341
342 for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
343 if (d->frpl)
344 ib_free_fast_reg_page_list(d->frpl);
345 if (d->mr)
346 ib_dereg_mr(d->mr);
347 }
348 kfree(pool);
349 }
350
351 /**
352 * srp_create_fr_pool() - allocate and initialize a pool for fast registration
353 * @device: IB device to allocate fast registration descriptors for.
354 * @pd: Protection domain associated with the FR descriptors.
355 * @pool_size: Number of descriptors to allocate.
356 * @max_page_list_len: Maximum fast registration work request page list length.
357 */
358 static struct srp_fr_pool *srp_create_fr_pool(struct ib_device *device,
359 struct ib_pd *pd, int pool_size,
360 int max_page_list_len)
361 {
362 struct srp_fr_pool *pool;
363 struct srp_fr_desc *d;
364 struct ib_mr *mr;
365 struct ib_fast_reg_page_list *frpl;
366 int i, ret = -EINVAL;
367
368 if (pool_size <= 0)
369 goto err;
370 ret = -ENOMEM;
371 pool = kzalloc(sizeof(struct srp_fr_pool) +
372 pool_size * sizeof(struct srp_fr_desc), GFP_KERNEL);
373 if (!pool)
374 goto err;
375 pool->size = pool_size;
376 pool->max_page_list_len = max_page_list_len;
377 spin_lock_init(&pool->lock);
378 INIT_LIST_HEAD(&pool->free_list);
379
380 for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
381 mr = ib_alloc_fast_reg_mr(pd, max_page_list_len);
382 if (IS_ERR(mr)) {
383 ret = PTR_ERR(mr);
384 goto destroy_pool;
385 }
386 d->mr = mr;
387 frpl = ib_alloc_fast_reg_page_list(device, max_page_list_len);
388 if (IS_ERR(frpl)) {
389 ret = PTR_ERR(frpl);
390 goto destroy_pool;
391 }
392 d->frpl = frpl;
393 list_add_tail(&d->entry, &pool->free_list);
394 }
395
396 out:
397 return pool;
398
399 destroy_pool:
400 srp_destroy_fr_pool(pool);
401
402 err:
403 pool = ERR_PTR(ret);
404 goto out;
405 }
406
407 /**
408 * srp_fr_pool_get() - obtain a descriptor suitable for fast registration
409 * @pool: Pool to obtain descriptor from.
410 */
411 static struct srp_fr_desc *srp_fr_pool_get(struct srp_fr_pool *pool)
412 {
413 struct srp_fr_desc *d = NULL;
414 unsigned long flags;
415
416 spin_lock_irqsave(&pool->lock, flags);
417 if (!list_empty(&pool->free_list)) {
418 d = list_first_entry(&pool->free_list, typeof(*d), entry);
419 list_del(&d->entry);
420 }
421 spin_unlock_irqrestore(&pool->lock, flags);
422
423 return d;
424 }
425
426 /**
427 * srp_fr_pool_put() - put an FR descriptor back in the free list
428 * @pool: Pool the descriptor was allocated from.
429 * @desc: Pointer to an array of fast registration descriptor pointers.
430 * @n: Number of descriptors to put back.
431 *
432 * Note: The caller must already have queued an invalidation request for
433 * desc->mr->rkey before calling this function.
434 */
435 static void srp_fr_pool_put(struct srp_fr_pool *pool, struct srp_fr_desc **desc,
436 int n)
437 {
438 unsigned long flags;
439 int i;
440
441 spin_lock_irqsave(&pool->lock, flags);
442 for (i = 0; i < n; i++)
443 list_add(&desc[i]->entry, &pool->free_list);
444 spin_unlock_irqrestore(&pool->lock, flags);
445 }
446
447 static struct srp_fr_pool *srp_alloc_fr_pool(struct srp_target_port *target)
448 {
449 struct srp_device *dev = target->srp_host->srp_dev;
450
451 return srp_create_fr_pool(dev->dev, dev->pd,
452 target->scsi_host->can_queue,
453 dev->max_pages_per_mr);
454 }
455
456 /**
457 * srp_destroy_qp() - destroy an RDMA queue pair
458 * @ch: SRP RDMA channel.
459 *
460 * Change a queue pair into the error state and wait until all receive
461 * completions have been processed before destroying it. This avoids that
462 * the receive completion handler can access the queue pair while it is
463 * being destroyed.
464 */
465 static void srp_destroy_qp(struct srp_rdma_ch *ch)
466 {
467 static struct ib_qp_attr attr = { .qp_state = IB_QPS_ERR };
468 static struct ib_recv_wr wr = { .wr_id = SRP_LAST_WR_ID };
469 struct ib_recv_wr *bad_wr;
470 int ret;
471
472 /* Destroying a QP and reusing ch->done is only safe if not connected */
473 WARN_ON_ONCE(ch->connected);
474
475 ret = ib_modify_qp(ch->qp, &attr, IB_QP_STATE);
476 WARN_ONCE(ret, "ib_cm_init_qp_attr() returned %d\n", ret);
477 if (ret)
478 goto out;
479
480 init_completion(&ch->done);
481 ret = ib_post_recv(ch->qp, &wr, &bad_wr);
482 WARN_ONCE(ret, "ib_post_recv() returned %d\n", ret);
483 if (ret == 0)
484 wait_for_completion(&ch->done);
485
486 out:
487 ib_destroy_qp(ch->qp);
488 }
489
490 static int srp_create_ch_ib(struct srp_rdma_ch *ch)
491 {
492 struct srp_target_port *target = ch->target;
493 struct srp_device *dev = target->srp_host->srp_dev;
494 struct ib_qp_init_attr *init_attr;
495 struct ib_cq *recv_cq, *send_cq;
496 struct ib_qp *qp;
497 struct ib_fmr_pool *fmr_pool = NULL;
498 struct srp_fr_pool *fr_pool = NULL;
499 const int m = 1 + dev->use_fast_reg;
500 struct ib_cq_init_attr cq_attr = {};
501 int ret;
502
503 init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
504 if (!init_attr)
505 return -ENOMEM;
506
507 /* + 1 for SRP_LAST_WR_ID */
508 cq_attr.cqe = target->queue_size + 1;
509 cq_attr.comp_vector = ch->comp_vector;
510 recv_cq = ib_create_cq(dev->dev, srp_recv_completion, NULL, ch,
511 &cq_attr);
512 if (IS_ERR(recv_cq)) {
513 ret = PTR_ERR(recv_cq);
514 goto err;
515 }
516
517 cq_attr.cqe = m * target->queue_size;
518 cq_attr.comp_vector = ch->comp_vector;
519 send_cq = ib_create_cq(dev->dev, srp_send_completion, NULL, ch,
520 &cq_attr);
521 if (IS_ERR(send_cq)) {
522 ret = PTR_ERR(send_cq);
523 goto err_recv_cq;
524 }
525
526 ib_req_notify_cq(recv_cq, IB_CQ_NEXT_COMP);
527
528 init_attr->event_handler = srp_qp_event;
529 init_attr->cap.max_send_wr = m * target->queue_size;
530 init_attr->cap.max_recv_wr = target->queue_size + 1;
531 init_attr->cap.max_recv_sge = 1;
532 init_attr->cap.max_send_sge = 1;
533 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
534 init_attr->qp_type = IB_QPT_RC;
535 init_attr->send_cq = send_cq;
536 init_attr->recv_cq = recv_cq;
537
538 qp = ib_create_qp(dev->pd, init_attr);
539 if (IS_ERR(qp)) {
540 ret = PTR_ERR(qp);
541 goto err_send_cq;
542 }
543
544 ret = srp_init_qp(target, qp);
545 if (ret)
546 goto err_qp;
547
548 if (dev->use_fast_reg && dev->has_fr) {
549 fr_pool = srp_alloc_fr_pool(target);
550 if (IS_ERR(fr_pool)) {
551 ret = PTR_ERR(fr_pool);
552 shost_printk(KERN_WARNING, target->scsi_host, PFX
553 "FR pool allocation failed (%d)\n", ret);
554 goto err_qp;
555 }
556 if (ch->fr_pool)
557 srp_destroy_fr_pool(ch->fr_pool);
558 ch->fr_pool = fr_pool;
559 } else if (!dev->use_fast_reg && dev->has_fmr) {
560 fmr_pool = srp_alloc_fmr_pool(target);
561 if (IS_ERR(fmr_pool)) {
562 ret = PTR_ERR(fmr_pool);
563 shost_printk(KERN_WARNING, target->scsi_host, PFX
564 "FMR pool allocation failed (%d)\n", ret);
565 goto err_qp;
566 }
567 if (ch->fmr_pool)
568 ib_destroy_fmr_pool(ch->fmr_pool);
569 ch->fmr_pool = fmr_pool;
570 }
571
572 if (ch->qp)
573 srp_destroy_qp(ch);
574 if (ch->recv_cq)
575 ib_destroy_cq(ch->recv_cq);
576 if (ch->send_cq)
577 ib_destroy_cq(ch->send_cq);
578
579 ch->qp = qp;
580 ch->recv_cq = recv_cq;
581 ch->send_cq = send_cq;
582
583 kfree(init_attr);
584 return 0;
585
586 err_qp:
587 ib_destroy_qp(qp);
588
589 err_send_cq:
590 ib_destroy_cq(send_cq);
591
592 err_recv_cq:
593 ib_destroy_cq(recv_cq);
594
595 err:
596 kfree(init_attr);
597 return ret;
598 }
599
600 /*
601 * Note: this function may be called without srp_alloc_iu_bufs() having been
602 * invoked. Hence the ch->[rt]x_ring checks.
603 */
604 static void srp_free_ch_ib(struct srp_target_port *target,
605 struct srp_rdma_ch *ch)
606 {
607 struct srp_device *dev = target->srp_host->srp_dev;
608 int i;
609
610 if (!ch->target)
611 return;
612
613 if (ch->cm_id) {
614 ib_destroy_cm_id(ch->cm_id);
615 ch->cm_id = NULL;
616 }
617
618 /* If srp_new_cm_id() succeeded but srp_create_ch_ib() not, return. */
619 if (!ch->qp)
620 return;
621
622 if (dev->use_fast_reg) {
623 if (ch->fr_pool)
624 srp_destroy_fr_pool(ch->fr_pool);
625 } else {
626 if (ch->fmr_pool)
627 ib_destroy_fmr_pool(ch->fmr_pool);
628 }
629 srp_destroy_qp(ch);
630 ib_destroy_cq(ch->send_cq);
631 ib_destroy_cq(ch->recv_cq);
632
633 /*
634 * Avoid that the SCSI error handler tries to use this channel after
635 * it has been freed. The SCSI error handler can namely continue
636 * trying to perform recovery actions after scsi_remove_host()
637 * returned.
638 */
639 ch->target = NULL;
640
641 ch->qp = NULL;
642 ch->send_cq = ch->recv_cq = NULL;
643
644 if (ch->rx_ring) {
645 for (i = 0; i < target->queue_size; ++i)
646 srp_free_iu(target->srp_host, ch->rx_ring[i]);
647 kfree(ch->rx_ring);
648 ch->rx_ring = NULL;
649 }
650 if (ch->tx_ring) {
651 for (i = 0; i < target->queue_size; ++i)
652 srp_free_iu(target->srp_host, ch->tx_ring[i]);
653 kfree(ch->tx_ring);
654 ch->tx_ring = NULL;
655 }
656 }
657
658 static void srp_path_rec_completion(int status,
659 struct ib_sa_path_rec *pathrec,
660 void *ch_ptr)
661 {
662 struct srp_rdma_ch *ch = ch_ptr;
663 struct srp_target_port *target = ch->target;
664
665 ch->status = status;
666 if (status)
667 shost_printk(KERN_ERR, target->scsi_host,
668 PFX "Got failed path rec status %d\n", status);
669 else
670 ch->path = *pathrec;
671 complete(&ch->done);
672 }
673
674 static int srp_lookup_path(struct srp_rdma_ch *ch)
675 {
676 struct srp_target_port *target = ch->target;
677 int ret;
678
679 ch->path.numb_path = 1;
680
681 init_completion(&ch->done);
682
683 ch->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
684 target->srp_host->srp_dev->dev,
685 target->srp_host->port,
686 &ch->path,
687 IB_SA_PATH_REC_SERVICE_ID |
688 IB_SA_PATH_REC_DGID |
689 IB_SA_PATH_REC_SGID |
690 IB_SA_PATH_REC_NUMB_PATH |
691 IB_SA_PATH_REC_PKEY,
692 SRP_PATH_REC_TIMEOUT_MS,
693 GFP_KERNEL,
694 srp_path_rec_completion,
695 ch, &ch->path_query);
696 if (ch->path_query_id < 0)
697 return ch->path_query_id;
698
699 ret = wait_for_completion_interruptible(&ch->done);
700 if (ret < 0)
701 return ret;
702
703 if (ch->status < 0)
704 shost_printk(KERN_WARNING, target->scsi_host,
705 PFX "Path record query failed\n");
706
707 return ch->status;
708 }
709
710 static int srp_send_req(struct srp_rdma_ch *ch, bool multich)
711 {
712 struct srp_target_port *target = ch->target;
713 struct {
714 struct ib_cm_req_param param;
715 struct srp_login_req priv;
716 } *req = NULL;
717 int status;
718
719 req = kzalloc(sizeof *req, GFP_KERNEL);
720 if (!req)
721 return -ENOMEM;
722
723 req->param.primary_path = &ch->path;
724 req->param.alternate_path = NULL;
725 req->param.service_id = target->service_id;
726 req->param.qp_num = ch->qp->qp_num;
727 req->param.qp_type = ch->qp->qp_type;
728 req->param.private_data = &req->priv;
729 req->param.private_data_len = sizeof req->priv;
730 req->param.flow_control = 1;
731
732 get_random_bytes(&req->param.starting_psn, 4);
733 req->param.starting_psn &= 0xffffff;
734
735 /*
736 * Pick some arbitrary defaults here; we could make these
737 * module parameters if anyone cared about setting them.
738 */
739 req->param.responder_resources = 4;
740 req->param.remote_cm_response_timeout = 20;
741 req->param.local_cm_response_timeout = 20;
742 req->param.retry_count = target->tl_retry_count;
743 req->param.rnr_retry_count = 7;
744 req->param.max_cm_retries = 15;
745
746 req->priv.opcode = SRP_LOGIN_REQ;
747 req->priv.tag = 0;
748 req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
749 req->priv.req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
750 SRP_BUF_FORMAT_INDIRECT);
751 req->priv.req_flags = (multich ? SRP_MULTICHAN_MULTI :
752 SRP_MULTICHAN_SINGLE);
753 /*
754 * In the published SRP specification (draft rev. 16a), the
755 * port identifier format is 8 bytes of ID extension followed
756 * by 8 bytes of GUID. Older drafts put the two halves in the
757 * opposite order, so that the GUID comes first.
758 *
759 * Targets conforming to these obsolete drafts can be
760 * recognized by the I/O Class they report.
761 */
762 if (target->io_class == SRP_REV10_IB_IO_CLASS) {
763 memcpy(req->priv.initiator_port_id,
764 &target->sgid.global.interface_id, 8);
765 memcpy(req->priv.initiator_port_id + 8,
766 &target->initiator_ext, 8);
767 memcpy(req->priv.target_port_id, &target->ioc_guid, 8);
768 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
769 } else {
770 memcpy(req->priv.initiator_port_id,
771 &target->initiator_ext, 8);
772 memcpy(req->priv.initiator_port_id + 8,
773 &target->sgid.global.interface_id, 8);
774 memcpy(req->priv.target_port_id, &target->id_ext, 8);
775 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
776 }
777
778 /*
779 * Topspin/Cisco SRP targets will reject our login unless we
780 * zero out the first 8 bytes of our initiator port ID and set
781 * the second 8 bytes to the local node GUID.
782 */
783 if (srp_target_is_topspin(target)) {
784 shost_printk(KERN_DEBUG, target->scsi_host,
785 PFX "Topspin/Cisco initiator port ID workaround "
786 "activated for target GUID %016llx\n",
787 be64_to_cpu(target->ioc_guid));
788 memset(req->priv.initiator_port_id, 0, 8);
789 memcpy(req->priv.initiator_port_id + 8,
790 &target->srp_host->srp_dev->dev->node_guid, 8);
791 }
792
793 status = ib_send_cm_req(ch->cm_id, &req->param);
794
795 kfree(req);
796
797 return status;
798 }
799
800 static bool srp_queue_remove_work(struct srp_target_port *target)
801 {
802 bool changed = false;
803
804 spin_lock_irq(&target->lock);
805 if (target->state != SRP_TARGET_REMOVED) {
806 target->state = SRP_TARGET_REMOVED;
807 changed = true;
808 }
809 spin_unlock_irq(&target->lock);
810
811 if (changed)
812 queue_work(srp_remove_wq, &target->remove_work);
813
814 return changed;
815 }
816
817 static void srp_disconnect_target(struct srp_target_port *target)
818 {
819 struct srp_rdma_ch *ch;
820 int i;
821
822 /* XXX should send SRP_I_LOGOUT request */
823
824 for (i = 0; i < target->ch_count; i++) {
825 ch = &target->ch[i];
826 ch->connected = false;
827 if (ch->cm_id && ib_send_cm_dreq(ch->cm_id, NULL, 0)) {
828 shost_printk(KERN_DEBUG, target->scsi_host,
829 PFX "Sending CM DREQ failed\n");
830 }
831 }
832 }
833
834 static void srp_free_req_data(struct srp_target_port *target,
835 struct srp_rdma_ch *ch)
836 {
837 struct srp_device *dev = target->srp_host->srp_dev;
838 struct ib_device *ibdev = dev->dev;
839 struct srp_request *req;
840 int i;
841
842 if (!ch->req_ring)
843 return;
844
845 for (i = 0; i < target->req_ring_size; ++i) {
846 req = &ch->req_ring[i];
847 if (dev->use_fast_reg)
848 kfree(req->fr_list);
849 else
850 kfree(req->fmr_list);
851 kfree(req->map_page);
852 if (req->indirect_dma_addr) {
853 ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
854 target->indirect_size,
855 DMA_TO_DEVICE);
856 }
857 kfree(req->indirect_desc);
858 }
859
860 kfree(ch->req_ring);
861 ch->req_ring = NULL;
862 }
863
864 static int srp_alloc_req_data(struct srp_rdma_ch *ch)
865 {
866 struct srp_target_port *target = ch->target;
867 struct srp_device *srp_dev = target->srp_host->srp_dev;
868 struct ib_device *ibdev = srp_dev->dev;
869 struct srp_request *req;
870 void *mr_list;
871 dma_addr_t dma_addr;
872 int i, ret = -ENOMEM;
873
874 ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
875 GFP_KERNEL);
876 if (!ch->req_ring)
877 goto out;
878
879 for (i = 0; i < target->req_ring_size; ++i) {
880 req = &ch->req_ring[i];
881 mr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
882 GFP_KERNEL);
883 if (!mr_list)
884 goto out;
885 if (srp_dev->use_fast_reg)
886 req->fr_list = mr_list;
887 else
888 req->fmr_list = mr_list;
889 req->map_page = kmalloc(srp_dev->max_pages_per_mr *
890 sizeof(void *), GFP_KERNEL);
891 if (!req->map_page)
892 goto out;
893 req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
894 if (!req->indirect_desc)
895 goto out;
896
897 dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
898 target->indirect_size,
899 DMA_TO_DEVICE);
900 if (ib_dma_mapping_error(ibdev, dma_addr))
901 goto out;
902
903 req->indirect_dma_addr = dma_addr;
904 }
905 ret = 0;
906
907 out:
908 return ret;
909 }
910
911 /**
912 * srp_del_scsi_host_attr() - Remove attributes defined in the host template.
913 * @shost: SCSI host whose attributes to remove from sysfs.
914 *
915 * Note: Any attributes defined in the host template and that did not exist
916 * before invocation of this function will be ignored.
917 */
918 static void srp_del_scsi_host_attr(struct Scsi_Host *shost)
919 {
920 struct device_attribute **attr;
921
922 for (attr = shost->hostt->shost_attrs; attr && *attr; ++attr)
923 device_remove_file(&shost->shost_dev, *attr);
924 }
925
926 static void srp_remove_target(struct srp_target_port *target)
927 {
928 struct srp_rdma_ch *ch;
929 int i;
930
931 WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
932
933 srp_del_scsi_host_attr(target->scsi_host);
934 srp_rport_get(target->rport);
935 srp_remove_host(target->scsi_host);
936 scsi_remove_host(target->scsi_host);
937 srp_stop_rport_timers(target->rport);
938 srp_disconnect_target(target);
939 for (i = 0; i < target->ch_count; i++) {
940 ch = &target->ch[i];
941 srp_free_ch_ib(target, ch);
942 }
943 cancel_work_sync(&target->tl_err_work);
944 srp_rport_put(target->rport);
945 for (i = 0; i < target->ch_count; i++) {
946 ch = &target->ch[i];
947 srp_free_req_data(target, ch);
948 }
949 kfree(target->ch);
950 target->ch = NULL;
951
952 spin_lock(&target->srp_host->target_lock);
953 list_del(&target->list);
954 spin_unlock(&target->srp_host->target_lock);
955
956 scsi_host_put(target->scsi_host);
957 }
958
959 static void srp_remove_work(struct work_struct *work)
960 {
961 struct srp_target_port *target =
962 container_of(work, struct srp_target_port, remove_work);
963
964 WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
965
966 srp_remove_target(target);
967 }
968
969 static void srp_rport_delete(struct srp_rport *rport)
970 {
971 struct srp_target_port *target = rport->lld_data;
972
973 srp_queue_remove_work(target);
974 }
975
976 /**
977 * srp_connected_ch() - number of connected channels
978 * @target: SRP target port.
979 */
980 static int srp_connected_ch(struct srp_target_port *target)
981 {
982 int i, c = 0;
983
984 for (i = 0; i < target->ch_count; i++)
985 c += target->ch[i].connected;
986
987 return c;
988 }
989
990 static int srp_connect_ch(struct srp_rdma_ch *ch, bool multich)
991 {
992 struct srp_target_port *target = ch->target;
993 int ret;
994
995 WARN_ON_ONCE(!multich && srp_connected_ch(target) > 0);
996
997 ret = srp_lookup_path(ch);
998 if (ret)
999 return ret;
1000
1001 while (1) {
1002 init_completion(&ch->done);
1003 ret = srp_send_req(ch, multich);
1004 if (ret)
1005 return ret;
1006 ret = wait_for_completion_interruptible(&ch->done);
1007 if (ret < 0)
1008 return ret;
1009
1010 /*
1011 * The CM event handling code will set status to
1012 * SRP_PORT_REDIRECT if we get a port redirect REJ
1013 * back, or SRP_DLID_REDIRECT if we get a lid/qp
1014 * redirect REJ back.
1015 */
1016 switch (ch->status) {
1017 case 0:
1018 ch->connected = true;
1019 return 0;
1020
1021 case SRP_PORT_REDIRECT:
1022 ret = srp_lookup_path(ch);
1023 if (ret)
1024 return ret;
1025 break;
1026
1027 case SRP_DLID_REDIRECT:
1028 break;
1029
1030 case SRP_STALE_CONN:
1031 shost_printk(KERN_ERR, target->scsi_host, PFX
1032 "giving up on stale connection\n");
1033 ch->status = -ECONNRESET;
1034 return ch->status;
1035
1036 default:
1037 return ch->status;
1038 }
1039 }
1040 }
1041
1042 static int srp_inv_rkey(struct srp_rdma_ch *ch, u32 rkey)
1043 {
1044 struct ib_send_wr *bad_wr;
1045 struct ib_send_wr wr = {
1046 .opcode = IB_WR_LOCAL_INV,
1047 .wr_id = LOCAL_INV_WR_ID_MASK,
1048 .next = NULL,
1049 .num_sge = 0,
1050 .send_flags = 0,
1051 .ex.invalidate_rkey = rkey,
1052 };
1053
1054 return ib_post_send(ch->qp, &wr, &bad_wr);
1055 }
1056
1057 static void srp_unmap_data(struct scsi_cmnd *scmnd,
1058 struct srp_rdma_ch *ch,
1059 struct srp_request *req)
1060 {
1061 struct srp_target_port *target = ch->target;
1062 struct srp_device *dev = target->srp_host->srp_dev;
1063 struct ib_device *ibdev = dev->dev;
1064 int i, res;
1065
1066 if (!scsi_sglist(scmnd) ||
1067 (scmnd->sc_data_direction != DMA_TO_DEVICE &&
1068 scmnd->sc_data_direction != DMA_FROM_DEVICE))
1069 return;
1070
1071 if (dev->use_fast_reg) {
1072 struct srp_fr_desc **pfr;
1073
1074 for (i = req->nmdesc, pfr = req->fr_list; i > 0; i--, pfr++) {
1075 res = srp_inv_rkey(ch, (*pfr)->mr->rkey);
1076 if (res < 0) {
1077 shost_printk(KERN_ERR, target->scsi_host, PFX
1078 "Queueing INV WR for rkey %#x failed (%d)\n",
1079 (*pfr)->mr->rkey, res);
1080 queue_work(system_long_wq,
1081 &target->tl_err_work);
1082 }
1083 }
1084 if (req->nmdesc)
1085 srp_fr_pool_put(ch->fr_pool, req->fr_list,
1086 req->nmdesc);
1087 } else {
1088 struct ib_pool_fmr **pfmr;
1089
1090 for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
1091 ib_fmr_pool_unmap(*pfmr);
1092 }
1093
1094 ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
1095 scmnd->sc_data_direction);
1096 }
1097
1098 /**
1099 * srp_claim_req - Take ownership of the scmnd associated with a request.
1100 * @ch: SRP RDMA channel.
1101 * @req: SRP request.
1102 * @sdev: If not NULL, only take ownership for this SCSI device.
1103 * @scmnd: If NULL, take ownership of @req->scmnd. If not NULL, only take
1104 * ownership of @req->scmnd if it equals @scmnd.
1105 *
1106 * Return value:
1107 * Either NULL or a pointer to the SCSI command the caller became owner of.
1108 */
1109 static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
1110 struct srp_request *req,
1111 struct scsi_device *sdev,
1112 struct scsi_cmnd *scmnd)
1113 {
1114 unsigned long flags;
1115
1116 spin_lock_irqsave(&ch->lock, flags);
1117 if (req->scmnd &&
1118 (!sdev || req->scmnd->device == sdev) &&
1119 (!scmnd || req->scmnd == scmnd)) {
1120 scmnd = req->scmnd;
1121 req->scmnd = NULL;
1122 } else {
1123 scmnd = NULL;
1124 }
1125 spin_unlock_irqrestore(&ch->lock, flags);
1126
1127 return scmnd;
1128 }
1129
1130 /**
1131 * srp_free_req() - Unmap data and add request to the free request list.
1132 * @ch: SRP RDMA channel.
1133 * @req: Request to be freed.
1134 * @scmnd: SCSI command associated with @req.
1135 * @req_lim_delta: Amount to be added to @target->req_lim.
1136 */
1137 static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
1138 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1139 {
1140 unsigned long flags;
1141
1142 srp_unmap_data(scmnd, ch, req);
1143
1144 spin_lock_irqsave(&ch->lock, flags);
1145 ch->req_lim += req_lim_delta;
1146 spin_unlock_irqrestore(&ch->lock, flags);
1147 }
1148
1149 static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
1150 struct scsi_device *sdev, int result)
1151 {
1152 struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
1153
1154 if (scmnd) {
1155 srp_free_req(ch, req, scmnd, 0);
1156 scmnd->result = result;
1157 scmnd->scsi_done(scmnd);
1158 }
1159 }
1160
1161 static void srp_terminate_io(struct srp_rport *rport)
1162 {
1163 struct srp_target_port *target = rport->lld_data;
1164 struct srp_rdma_ch *ch;
1165 struct Scsi_Host *shost = target->scsi_host;
1166 struct scsi_device *sdev;
1167 int i, j;
1168
1169 /*
1170 * Invoking srp_terminate_io() while srp_queuecommand() is running
1171 * is not safe. Hence the warning statement below.
1172 */
1173 shost_for_each_device(sdev, shost)
1174 WARN_ON_ONCE(sdev->request_queue->request_fn_active);
1175
1176 for (i = 0; i < target->ch_count; i++) {
1177 ch = &target->ch[i];
1178
1179 for (j = 0; j < target->req_ring_size; ++j) {
1180 struct srp_request *req = &ch->req_ring[j];
1181
1182 srp_finish_req(ch, req, NULL,
1183 DID_TRANSPORT_FAILFAST << 16);
1184 }
1185 }
1186 }
1187
1188 /*
1189 * It is up to the caller to ensure that srp_rport_reconnect() calls are
1190 * serialized and that no concurrent srp_queuecommand(), srp_abort(),
1191 * srp_reset_device() or srp_reset_host() calls will occur while this function
1192 * is in progress. One way to realize that is not to call this function
1193 * directly but to call srp_reconnect_rport() instead since that last function
1194 * serializes calls of this function via rport->mutex and also blocks
1195 * srp_queuecommand() calls before invoking this function.
1196 */
1197 static int srp_rport_reconnect(struct srp_rport *rport)
1198 {
1199 struct srp_target_port *target = rport->lld_data;
1200 struct srp_rdma_ch *ch;
1201 int i, j, ret = 0;
1202 bool multich = false;
1203
1204 srp_disconnect_target(target);
1205
1206 if (target->state == SRP_TARGET_SCANNING)
1207 return -ENODEV;
1208
1209 /*
1210 * Now get a new local CM ID so that we avoid confusing the target in
1211 * case things are really fouled up. Doing so also ensures that all CM
1212 * callbacks will have finished before a new QP is allocated.
1213 */
1214 for (i = 0; i < target->ch_count; i++) {
1215 ch = &target->ch[i];
1216 ret += srp_new_cm_id(ch);
1217 }
1218 for (i = 0; i < target->ch_count; i++) {
1219 ch = &target->ch[i];
1220 for (j = 0; j < target->req_ring_size; ++j) {
1221 struct srp_request *req = &ch->req_ring[j];
1222
1223 srp_finish_req(ch, req, NULL, DID_RESET << 16);
1224 }
1225 }
1226 for (i = 0; i < target->ch_count; i++) {
1227 ch = &target->ch[i];
1228 /*
1229 * Whether or not creating a new CM ID succeeded, create a new
1230 * QP. This guarantees that all completion callback function
1231 * invocations have finished before request resetting starts.
1232 */
1233 ret += srp_create_ch_ib(ch);
1234
1235 INIT_LIST_HEAD(&ch->free_tx);
1236 for (j = 0; j < target->queue_size; ++j)
1237 list_add(&ch->tx_ring[j]->list, &ch->free_tx);
1238 }
1239
1240 target->qp_in_error = false;
1241
1242 for (i = 0; i < target->ch_count; i++) {
1243 ch = &target->ch[i];
1244 if (ret)
1245 break;
1246 ret = srp_connect_ch(ch, multich);
1247 multich = true;
1248 }
1249
1250 if (ret == 0)
1251 shost_printk(KERN_INFO, target->scsi_host,
1252 PFX "reconnect succeeded\n");
1253
1254 return ret;
1255 }
1256
1257 static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
1258 unsigned int dma_len, u32 rkey)
1259 {
1260 struct srp_direct_buf *desc = state->desc;
1261
1262 desc->va = cpu_to_be64(dma_addr);
1263 desc->key = cpu_to_be32(rkey);
1264 desc->len = cpu_to_be32(dma_len);
1265
1266 state->total_len += dma_len;
1267 state->desc++;
1268 state->ndesc++;
1269 }
1270
1271 static int srp_map_finish_fmr(struct srp_map_state *state,
1272 struct srp_rdma_ch *ch)
1273 {
1274 struct ib_pool_fmr *fmr;
1275 u64 io_addr = 0;
1276
1277 fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1278 state->npages, io_addr);
1279 if (IS_ERR(fmr))
1280 return PTR_ERR(fmr);
1281
1282 *state->next_fmr++ = fmr;
1283 state->nmdesc++;
1284
1285 srp_map_desc(state, 0, state->dma_len, fmr->fmr->rkey);
1286
1287 return 0;
1288 }
1289
1290 static int srp_map_finish_fr(struct srp_map_state *state,
1291 struct srp_rdma_ch *ch)
1292 {
1293 struct srp_target_port *target = ch->target;
1294 struct srp_device *dev = target->srp_host->srp_dev;
1295 struct ib_send_wr *bad_wr;
1296 struct ib_send_wr wr;
1297 struct srp_fr_desc *desc;
1298 u32 rkey;
1299
1300 desc = srp_fr_pool_get(ch->fr_pool);
1301 if (!desc)
1302 return -ENOMEM;
1303
1304 rkey = ib_inc_rkey(desc->mr->rkey);
1305 ib_update_fast_reg_key(desc->mr, rkey);
1306
1307 memcpy(desc->frpl->page_list, state->pages,
1308 sizeof(state->pages[0]) * state->npages);
1309
1310 memset(&wr, 0, sizeof(wr));
1311 wr.opcode = IB_WR_FAST_REG_MR;
1312 wr.wr_id = FAST_REG_WR_ID_MASK;
1313 wr.wr.fast_reg.iova_start = state->base_dma_addr;
1314 wr.wr.fast_reg.page_list = desc->frpl;
1315 wr.wr.fast_reg.page_list_len = state->npages;
1316 wr.wr.fast_reg.page_shift = ilog2(dev->mr_page_size);
1317 wr.wr.fast_reg.length = state->dma_len;
1318 wr.wr.fast_reg.access_flags = (IB_ACCESS_LOCAL_WRITE |
1319 IB_ACCESS_REMOTE_READ |
1320 IB_ACCESS_REMOTE_WRITE);
1321 wr.wr.fast_reg.rkey = desc->mr->lkey;
1322
1323 *state->next_fr++ = desc;
1324 state->nmdesc++;
1325
1326 srp_map_desc(state, state->base_dma_addr, state->dma_len,
1327 desc->mr->rkey);
1328
1329 return ib_post_send(ch->qp, &wr, &bad_wr);
1330 }
1331
1332 static int srp_finish_mapping(struct srp_map_state *state,
1333 struct srp_rdma_ch *ch)
1334 {
1335 struct srp_target_port *target = ch->target;
1336 int ret = 0;
1337
1338 if (state->npages == 0)
1339 return 0;
1340
1341 if (state->npages == 1 && !register_always)
1342 srp_map_desc(state, state->base_dma_addr, state->dma_len,
1343 target->rkey);
1344 else
1345 ret = target->srp_host->srp_dev->use_fast_reg ?
1346 srp_map_finish_fr(state, ch) :
1347 srp_map_finish_fmr(state, ch);
1348
1349 if (ret == 0) {
1350 state->npages = 0;
1351 state->dma_len = 0;
1352 }
1353
1354 return ret;
1355 }
1356
1357 static void srp_map_update_start(struct srp_map_state *state,
1358 struct scatterlist *sg, int sg_index,
1359 dma_addr_t dma_addr)
1360 {
1361 state->unmapped_sg = sg;
1362 state->unmapped_index = sg_index;
1363 state->unmapped_addr = dma_addr;
1364 }
1365
1366 static int srp_map_sg_entry(struct srp_map_state *state,
1367 struct srp_rdma_ch *ch,
1368 struct scatterlist *sg, int sg_index,
1369 bool use_mr)
1370 {
1371 struct srp_target_port *target = ch->target;
1372 struct srp_device *dev = target->srp_host->srp_dev;
1373 struct ib_device *ibdev = dev->dev;
1374 dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
1375 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
1376 unsigned int len;
1377 int ret;
1378
1379 if (!dma_len)
1380 return 0;
1381
1382 if (!use_mr) {
1383 /*
1384 * Once we're in direct map mode for a request, we don't
1385 * go back to FMR or FR mode, so no need to update anything
1386 * other than the descriptor.
1387 */
1388 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1389 return 0;
1390 }
1391
1392 /*
1393 * Since not all RDMA HW drivers support non-zero page offsets for
1394 * FMR, if we start at an offset into a page, don't merge into the
1395 * current FMR mapping. Finish it out, and use the kernel's MR for
1396 * this sg entry.
1397 */
1398 if ((!dev->use_fast_reg && dma_addr & ~dev->mr_page_mask) ||
1399 dma_len > dev->mr_max_size) {
1400 ret = srp_finish_mapping(state, ch);
1401 if (ret)
1402 return ret;
1403
1404 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1405 srp_map_update_start(state, NULL, 0, 0);
1406 return 0;
1407 }
1408
1409 /*
1410 * If this is the first sg that will be mapped via FMR or via FR, save
1411 * our position. We need to know the first unmapped entry, its index,
1412 * and the first unmapped address within that entry to be able to
1413 * restart mapping after an error.
1414 */
1415 if (!state->unmapped_sg)
1416 srp_map_update_start(state, sg, sg_index, dma_addr);
1417
1418 while (dma_len) {
1419 unsigned offset = dma_addr & ~dev->mr_page_mask;
1420 if (state->npages == dev->max_pages_per_mr || offset != 0) {
1421 ret = srp_finish_mapping(state, ch);
1422 if (ret)
1423 return ret;
1424
1425 srp_map_update_start(state, sg, sg_index, dma_addr);
1426 }
1427
1428 len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1429
1430 if (!state->npages)
1431 state->base_dma_addr = dma_addr;
1432 state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1433 state->dma_len += len;
1434 dma_addr += len;
1435 dma_len -= len;
1436 }
1437
1438 /*
1439 * If the last entry of the MR wasn't a full page, then we need to
1440 * close it out and start a new one -- we can only merge at page
1441 * boundries.
1442 */
1443 ret = 0;
1444 if (len != dev->mr_page_size) {
1445 ret = srp_finish_mapping(state, ch);
1446 if (!ret)
1447 srp_map_update_start(state, NULL, 0, 0);
1448 }
1449 return ret;
1450 }
1451
1452 static int srp_map_sg(struct srp_map_state *state, struct srp_rdma_ch *ch,
1453 struct srp_request *req, struct scatterlist *scat,
1454 int count)
1455 {
1456 struct srp_target_port *target = ch->target;
1457 struct srp_device *dev = target->srp_host->srp_dev;
1458 struct ib_device *ibdev = dev->dev;
1459 struct scatterlist *sg;
1460 int i;
1461 bool use_mr;
1462
1463 state->desc = req->indirect_desc;
1464 state->pages = req->map_page;
1465 if (dev->use_fast_reg) {
1466 state->next_fr = req->fr_list;
1467 use_mr = !!ch->fr_pool;
1468 } else {
1469 state->next_fmr = req->fmr_list;
1470 use_mr = !!ch->fmr_pool;
1471 }
1472
1473 for_each_sg(scat, sg, count, i) {
1474 if (srp_map_sg_entry(state, ch, sg, i, use_mr)) {
1475 /*
1476 * Memory registration failed, so backtrack to the
1477 * first unmapped entry and continue on without using
1478 * memory registration.
1479 */
1480 dma_addr_t dma_addr;
1481 unsigned int dma_len;
1482
1483 backtrack:
1484 sg = state->unmapped_sg;
1485 i = state->unmapped_index;
1486
1487 dma_addr = ib_sg_dma_address(ibdev, sg);
1488 dma_len = ib_sg_dma_len(ibdev, sg);
1489 dma_len -= (state->unmapped_addr - dma_addr);
1490 dma_addr = state->unmapped_addr;
1491 use_mr = false;
1492 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1493 }
1494 }
1495
1496 if (use_mr && srp_finish_mapping(state, ch))
1497 goto backtrack;
1498
1499 req->nmdesc = state->nmdesc;
1500
1501 return 0;
1502 }
1503
1504 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1505 struct srp_request *req)
1506 {
1507 struct srp_target_port *target = ch->target;
1508 struct scatterlist *scat;
1509 struct srp_cmd *cmd = req->cmd->buf;
1510 int len, nents, count;
1511 struct srp_device *dev;
1512 struct ib_device *ibdev;
1513 struct srp_map_state state;
1514 struct srp_indirect_buf *indirect_hdr;
1515 u32 table_len;
1516 u8 fmt;
1517
1518 if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1519 return sizeof (struct srp_cmd);
1520
1521 if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
1522 scmnd->sc_data_direction != DMA_TO_DEVICE) {
1523 shost_printk(KERN_WARNING, target->scsi_host,
1524 PFX "Unhandled data direction %d\n",
1525 scmnd->sc_data_direction);
1526 return -EINVAL;
1527 }
1528
1529 nents = scsi_sg_count(scmnd);
1530 scat = scsi_sglist(scmnd);
1531
1532 dev = target->srp_host->srp_dev;
1533 ibdev = dev->dev;
1534
1535 count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1536 if (unlikely(count == 0))
1537 return -EIO;
1538
1539 fmt = SRP_DATA_DESC_DIRECT;
1540 len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
1541
1542 if (count == 1 && !register_always) {
1543 /*
1544 * The midlayer only generated a single gather/scatter
1545 * entry, or DMA mapping coalesced everything to a
1546 * single entry. So a direct descriptor along with
1547 * the DMA MR suffices.
1548 */
1549 struct srp_direct_buf *buf = (void *) cmd->add_data;
1550
1551 buf->va = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
1552 buf->key = cpu_to_be32(target->rkey);
1553 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1554
1555 req->nmdesc = 0;
1556 goto map_complete;
1557 }
1558
1559 /*
1560 * We have more than one scatter/gather entry, so build our indirect
1561 * descriptor table, trying to merge as many entries as we can.
1562 */
1563 indirect_hdr = (void *) cmd->add_data;
1564
1565 ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
1566 target->indirect_size, DMA_TO_DEVICE);
1567
1568 memset(&state, 0, sizeof(state));
1569 srp_map_sg(&state, ch, req, scat, count);
1570
1571 /* We've mapped the request, now pull as much of the indirect
1572 * descriptor table as we can into the command buffer. If this
1573 * target is not using an external indirect table, we are
1574 * guaranteed to fit into the command, as the SCSI layer won't
1575 * give us more S/G entries than we allow.
1576 */
1577 if (state.ndesc == 1) {
1578 /*
1579 * Memory registration collapsed the sg-list into one entry,
1580 * so use a direct descriptor.
1581 */
1582 struct srp_direct_buf *buf = (void *) cmd->add_data;
1583
1584 *buf = req->indirect_desc[0];
1585 goto map_complete;
1586 }
1587
1588 if (unlikely(target->cmd_sg_cnt < state.ndesc &&
1589 !target->allow_ext_sg)) {
1590 shost_printk(KERN_ERR, target->scsi_host,
1591 "Could not fit S/G list into SRP_CMD\n");
1592 return -EIO;
1593 }
1594
1595 count = min(state.ndesc, target->cmd_sg_cnt);
1596 table_len = state.ndesc * sizeof (struct srp_direct_buf);
1597
1598 fmt = SRP_DATA_DESC_INDIRECT;
1599 len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1600 len += count * sizeof (struct srp_direct_buf);
1601
1602 memcpy(indirect_hdr->desc_list, req->indirect_desc,
1603 count * sizeof (struct srp_direct_buf));
1604
1605 indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1606 indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
1607 indirect_hdr->table_desc.len = cpu_to_be32(table_len);
1608 indirect_hdr->len = cpu_to_be32(state.total_len);
1609
1610 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
1611 cmd->data_out_desc_cnt = count;
1612 else
1613 cmd->data_in_desc_cnt = count;
1614
1615 ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
1616 DMA_TO_DEVICE);
1617
1618 map_complete:
1619 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
1620 cmd->buf_fmt = fmt << 4;
1621 else
1622 cmd->buf_fmt = fmt;
1623
1624 return len;
1625 }
1626
1627 /*
1628 * Return an IU and possible credit to the free pool
1629 */
1630 static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1631 enum srp_iu_type iu_type)
1632 {
1633 unsigned long flags;
1634
1635 spin_lock_irqsave(&ch->lock, flags);
1636 list_add(&iu->list, &ch->free_tx);
1637 if (iu_type != SRP_IU_RSP)
1638 ++ch->req_lim;
1639 spin_unlock_irqrestore(&ch->lock, flags);
1640 }
1641
1642 /*
1643 * Must be called with ch->lock held to protect req_lim and free_tx.
1644 * If IU is not sent, it must be returned using srp_put_tx_iu().
1645 *
1646 * Note:
1647 * An upper limit for the number of allocated information units for each
1648 * request type is:
1649 * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
1650 * more than Scsi_Host.can_queue requests.
1651 * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
1652 * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
1653 * one unanswered SRP request to an initiator.
1654 */
1655 static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
1656 enum srp_iu_type iu_type)
1657 {
1658 struct srp_target_port *target = ch->target;
1659 s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
1660 struct srp_iu *iu;
1661
1662 srp_send_completion(ch->send_cq, ch);
1663
1664 if (list_empty(&ch->free_tx))
1665 return NULL;
1666
1667 /* Initiator responses to target requests do not consume credits */
1668 if (iu_type != SRP_IU_RSP) {
1669 if (ch->req_lim <= rsv) {
1670 ++target->zero_req_lim;
1671 return NULL;
1672 }
1673
1674 --ch->req_lim;
1675 }
1676
1677 iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
1678 list_del(&iu->list);
1679 return iu;
1680 }
1681
1682 static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
1683 {
1684 struct srp_target_port *target = ch->target;
1685 struct ib_sge list;
1686 struct ib_send_wr wr, *bad_wr;
1687
1688 list.addr = iu->dma;
1689 list.length = len;
1690 list.lkey = target->lkey;
1691
1692 wr.next = NULL;
1693 wr.wr_id = (uintptr_t) iu;
1694 wr.sg_list = &list;
1695 wr.num_sge = 1;
1696 wr.opcode = IB_WR_SEND;
1697 wr.send_flags = IB_SEND_SIGNALED;
1698
1699 return ib_post_send(ch->qp, &wr, &bad_wr);
1700 }
1701
1702 static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
1703 {
1704 struct srp_target_port *target = ch->target;
1705 struct ib_recv_wr wr, *bad_wr;
1706 struct ib_sge list;
1707
1708 list.addr = iu->dma;
1709 list.length = iu->size;
1710 list.lkey = target->lkey;
1711
1712 wr.next = NULL;
1713 wr.wr_id = (uintptr_t) iu;
1714 wr.sg_list = &list;
1715 wr.num_sge = 1;
1716
1717 return ib_post_recv(ch->qp, &wr, &bad_wr);
1718 }
1719
1720 static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
1721 {
1722 struct srp_target_port *target = ch->target;
1723 struct srp_request *req;
1724 struct scsi_cmnd *scmnd;
1725 unsigned long flags;
1726
1727 if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1728 spin_lock_irqsave(&ch->lock, flags);
1729 ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
1730 spin_unlock_irqrestore(&ch->lock, flags);
1731
1732 ch->tsk_mgmt_status = -1;
1733 if (be32_to_cpu(rsp->resp_data_len) >= 4)
1734 ch->tsk_mgmt_status = rsp->data[3];
1735 complete(&ch->tsk_mgmt_done);
1736 } else {
1737 scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag);
1738 if (scmnd) {
1739 req = (void *)scmnd->host_scribble;
1740 scmnd = srp_claim_req(ch, req, NULL, scmnd);
1741 }
1742 if (!scmnd) {
1743 shost_printk(KERN_ERR, target->scsi_host,
1744 "Null scmnd for RSP w/tag %#016llx received on ch %td / QP %#x\n",
1745 rsp->tag, ch - target->ch, ch->qp->qp_num);
1746
1747 spin_lock_irqsave(&ch->lock, flags);
1748 ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
1749 spin_unlock_irqrestore(&ch->lock, flags);
1750
1751 return;
1752 }
1753 scmnd->result = rsp->status;
1754
1755 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
1756 memcpy(scmnd->sense_buffer, rsp->data +
1757 be32_to_cpu(rsp->resp_data_len),
1758 min_t(int, be32_to_cpu(rsp->sense_data_len),
1759 SCSI_SENSE_BUFFERSIZE));
1760 }
1761
1762 if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
1763 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
1764 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DIOVER))
1765 scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_in_res_cnt));
1766 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOUNDER))
1767 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
1768 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOOVER))
1769 scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_out_res_cnt));
1770
1771 srp_free_req(ch, req, scmnd,
1772 be32_to_cpu(rsp->req_lim_delta));
1773
1774 scmnd->host_scribble = NULL;
1775 scmnd->scsi_done(scmnd);
1776 }
1777 }
1778
1779 static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
1780 void *rsp, int len)
1781 {
1782 struct srp_target_port *target = ch->target;
1783 struct ib_device *dev = target->srp_host->srp_dev->dev;
1784 unsigned long flags;
1785 struct srp_iu *iu;
1786 int err;
1787
1788 spin_lock_irqsave(&ch->lock, flags);
1789 ch->req_lim += req_delta;
1790 iu = __srp_get_tx_iu(ch, SRP_IU_RSP);
1791 spin_unlock_irqrestore(&ch->lock, flags);
1792
1793 if (!iu) {
1794 shost_printk(KERN_ERR, target->scsi_host, PFX
1795 "no IU available to send response\n");
1796 return 1;
1797 }
1798
1799 ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
1800 memcpy(iu->buf, rsp, len);
1801 ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
1802
1803 err = srp_post_send(ch, iu, len);
1804 if (err) {
1805 shost_printk(KERN_ERR, target->scsi_host, PFX
1806 "unable to post response: %d\n", err);
1807 srp_put_tx_iu(ch, iu, SRP_IU_RSP);
1808 }
1809
1810 return err;
1811 }
1812
1813 static void srp_process_cred_req(struct srp_rdma_ch *ch,
1814 struct srp_cred_req *req)
1815 {
1816 struct srp_cred_rsp rsp = {
1817 .opcode = SRP_CRED_RSP,
1818 .tag = req->tag,
1819 };
1820 s32 delta = be32_to_cpu(req->req_lim_delta);
1821
1822 if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
1823 shost_printk(KERN_ERR, ch->target->scsi_host, PFX
1824 "problems processing SRP_CRED_REQ\n");
1825 }
1826
1827 static void srp_process_aer_req(struct srp_rdma_ch *ch,
1828 struct srp_aer_req *req)
1829 {
1830 struct srp_target_port *target = ch->target;
1831 struct srp_aer_rsp rsp = {
1832 .opcode = SRP_AER_RSP,
1833 .tag = req->tag,
1834 };
1835 s32 delta = be32_to_cpu(req->req_lim_delta);
1836
1837 shost_printk(KERN_ERR, target->scsi_host, PFX
1838 "ignoring AER for LUN %llu\n", scsilun_to_int(&req->lun));
1839
1840 if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
1841 shost_printk(KERN_ERR, target->scsi_host, PFX
1842 "problems processing SRP_AER_REQ\n");
1843 }
1844
1845 static void srp_handle_recv(struct srp_rdma_ch *ch, struct ib_wc *wc)
1846 {
1847 struct srp_target_port *target = ch->target;
1848 struct ib_device *dev = target->srp_host->srp_dev->dev;
1849 struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
1850 int res;
1851 u8 opcode;
1852
1853 ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
1854 DMA_FROM_DEVICE);
1855
1856 opcode = *(u8 *) iu->buf;
1857
1858 if (0) {
1859 shost_printk(KERN_ERR, target->scsi_host,
1860 PFX "recv completion, opcode 0x%02x\n", opcode);
1861 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1862 iu->buf, wc->byte_len, true);
1863 }
1864
1865 switch (opcode) {
1866 case SRP_RSP:
1867 srp_process_rsp(ch, iu->buf);
1868 break;
1869
1870 case SRP_CRED_REQ:
1871 srp_process_cred_req(ch, iu->buf);
1872 break;
1873
1874 case SRP_AER_REQ:
1875 srp_process_aer_req(ch, iu->buf);
1876 break;
1877
1878 case SRP_T_LOGOUT:
1879 /* XXX Handle target logout */
1880 shost_printk(KERN_WARNING, target->scsi_host,
1881 PFX "Got target logout request\n");
1882 break;
1883
1884 default:
1885 shost_printk(KERN_WARNING, target->scsi_host,
1886 PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1887 break;
1888 }
1889
1890 ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
1891 DMA_FROM_DEVICE);
1892
1893 res = srp_post_recv(ch, iu);
1894 if (res != 0)
1895 shost_printk(KERN_ERR, target->scsi_host,
1896 PFX "Recv failed with error code %d\n", res);
1897 }
1898
1899 /**
1900 * srp_tl_err_work() - handle a transport layer error
1901 * @work: Work structure embedded in an SRP target port.
1902 *
1903 * Note: This function may get invoked before the rport has been created,
1904 * hence the target->rport test.
1905 */
1906 static void srp_tl_err_work(struct work_struct *work)
1907 {
1908 struct srp_target_port *target;
1909
1910 target = container_of(work, struct srp_target_port, tl_err_work);
1911 if (target->rport)
1912 srp_start_tl_fail_timers(target->rport);
1913 }
1914
1915 static void srp_handle_qp_err(u64 wr_id, enum ib_wc_status wc_status,
1916 bool send_err, struct srp_rdma_ch *ch)
1917 {
1918 struct srp_target_port *target = ch->target;
1919
1920 if (wr_id == SRP_LAST_WR_ID) {
1921 complete(&ch->done);
1922 return;
1923 }
1924
1925 if (ch->connected && !target->qp_in_error) {
1926 if (wr_id & LOCAL_INV_WR_ID_MASK) {
1927 shost_printk(KERN_ERR, target->scsi_host, PFX
1928 "LOCAL_INV failed with status %s (%d)\n",
1929 ib_wc_status_msg(wc_status), wc_status);
1930 } else if (wr_id & FAST_REG_WR_ID_MASK) {
1931 shost_printk(KERN_ERR, target->scsi_host, PFX
1932 "FAST_REG_MR failed status %s (%d)\n",
1933 ib_wc_status_msg(wc_status), wc_status);
1934 } else {
1935 shost_printk(KERN_ERR, target->scsi_host,
1936 PFX "failed %s status %s (%d) for iu %p\n",
1937 send_err ? "send" : "receive",
1938 ib_wc_status_msg(wc_status), wc_status,
1939 (void *)(uintptr_t)wr_id);
1940 }
1941 queue_work(system_long_wq, &target->tl_err_work);
1942 }
1943 target->qp_in_error = true;
1944 }
1945
1946 static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr)
1947 {
1948 struct srp_rdma_ch *ch = ch_ptr;
1949 struct ib_wc wc;
1950
1951 ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1952 while (ib_poll_cq(cq, 1, &wc) > 0) {
1953 if (likely(wc.status == IB_WC_SUCCESS)) {
1954 srp_handle_recv(ch, &wc);
1955 } else {
1956 srp_handle_qp_err(wc.wr_id, wc.status, false, ch);
1957 }
1958 }
1959 }
1960
1961 static void srp_send_completion(struct ib_cq *cq, void *ch_ptr)
1962 {
1963 struct srp_rdma_ch *ch = ch_ptr;
1964 struct ib_wc wc;
1965 struct srp_iu *iu;
1966
1967 while (ib_poll_cq(cq, 1, &wc) > 0) {
1968 if (likely(wc.status == IB_WC_SUCCESS)) {
1969 iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
1970 list_add(&iu->list, &ch->free_tx);
1971 } else {
1972 srp_handle_qp_err(wc.wr_id, wc.status, true, ch);
1973 }
1974 }
1975 }
1976
1977 static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1978 {
1979 struct srp_target_port *target = host_to_target(shost);
1980 struct srp_rport *rport = target->rport;
1981 struct srp_rdma_ch *ch;
1982 struct srp_request *req;
1983 struct srp_iu *iu;
1984 struct srp_cmd *cmd;
1985 struct ib_device *dev;
1986 unsigned long flags;
1987 u32 tag;
1988 u16 idx;
1989 int len, ret;
1990 const bool in_scsi_eh = !in_interrupt() && current == shost->ehandler;
1991
1992 /*
1993 * The SCSI EH thread is the only context from which srp_queuecommand()
1994 * can get invoked for blocked devices (SDEV_BLOCK /
1995 * SDEV_CREATED_BLOCK). Avoid racing with srp_reconnect_rport() by
1996 * locking the rport mutex if invoked from inside the SCSI EH.
1997 */
1998 if (in_scsi_eh)
1999 mutex_lock(&rport->mutex);
2000
2001 scmnd->result = srp_chkready(target->rport);
2002 if (unlikely(scmnd->result))
2003 goto err;
2004
2005 WARN_ON_ONCE(scmnd->request->tag < 0);
2006 tag = blk_mq_unique_tag(scmnd->request);
2007 ch = &target->ch[blk_mq_unique_tag_to_hwq(tag)];
2008 idx = blk_mq_unique_tag_to_tag(tag);
2009 WARN_ONCE(idx >= target->req_ring_size, "%s: tag %#x: idx %d >= %d\n",
2010 dev_name(&shost->shost_gendev), tag, idx,
2011 target->req_ring_size);
2012
2013 spin_lock_irqsave(&ch->lock, flags);
2014 iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
2015 spin_unlock_irqrestore(&ch->lock, flags);
2016
2017 if (!iu)
2018 goto err;
2019
2020 req = &ch->req_ring[idx];
2021 dev = target->srp_host->srp_dev->dev;
2022 ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
2023 DMA_TO_DEVICE);
2024
2025 scmnd->host_scribble = (void *) req;
2026
2027 cmd = iu->buf;
2028 memset(cmd, 0, sizeof *cmd);
2029
2030 cmd->opcode = SRP_CMD;
2031 int_to_scsilun(scmnd->device->lun, &cmd->lun);
2032 cmd->tag = tag;
2033 memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
2034
2035 req->scmnd = scmnd;
2036 req->cmd = iu;
2037
2038 len = srp_map_data(scmnd, ch, req);
2039 if (len < 0) {
2040 shost_printk(KERN_ERR, target->scsi_host,
2041 PFX "Failed to map data (%d)\n", len);
2042 /*
2043 * If we ran out of memory descriptors (-ENOMEM) because an
2044 * application is queuing many requests with more than
2045 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
2046 * to reduce queue depth temporarily.
2047 */
2048 scmnd->result = len == -ENOMEM ?
2049 DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
2050 goto err_iu;
2051 }
2052
2053 ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
2054 DMA_TO_DEVICE);
2055
2056 if (srp_post_send(ch, iu, len)) {
2057 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
2058 goto err_unmap;
2059 }
2060
2061 ret = 0;
2062
2063 unlock_rport:
2064 if (in_scsi_eh)
2065 mutex_unlock(&rport->mutex);
2066
2067 return ret;
2068
2069 err_unmap:
2070 srp_unmap_data(scmnd, ch, req);
2071
2072 err_iu:
2073 srp_put_tx_iu(ch, iu, SRP_IU_CMD);
2074
2075 /*
2076 * Avoid that the loops that iterate over the request ring can
2077 * encounter a dangling SCSI command pointer.
2078 */
2079 req->scmnd = NULL;
2080
2081 err:
2082 if (scmnd->result) {
2083 scmnd->scsi_done(scmnd);
2084 ret = 0;
2085 } else {
2086 ret = SCSI_MLQUEUE_HOST_BUSY;
2087 }
2088
2089 goto unlock_rport;
2090 }
2091
2092 /*
2093 * Note: the resources allocated in this function are freed in
2094 * srp_free_ch_ib().
2095 */
2096 static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2097 {
2098 struct srp_target_port *target = ch->target;
2099 int i;
2100
2101 ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
2102 GFP_KERNEL);
2103 if (!ch->rx_ring)
2104 goto err_no_ring;
2105 ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
2106 GFP_KERNEL);
2107 if (!ch->tx_ring)
2108 goto err_no_ring;
2109
2110 for (i = 0; i < target->queue_size; ++i) {
2111 ch->rx_ring[i] = srp_alloc_iu(target->srp_host,
2112 ch->max_ti_iu_len,
2113 GFP_KERNEL, DMA_FROM_DEVICE);
2114 if (!ch->rx_ring[i])
2115 goto err;
2116 }
2117
2118 for (i = 0; i < target->queue_size; ++i) {
2119 ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
2120 target->max_iu_len,
2121 GFP_KERNEL, DMA_TO_DEVICE);
2122 if (!ch->tx_ring[i])
2123 goto err;
2124
2125 list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2126 }
2127
2128 return 0;
2129
2130 err:
2131 for (i = 0; i < target->queue_size; ++i) {
2132 srp_free_iu(target->srp_host, ch->rx_ring[i]);
2133 srp_free_iu(target->srp_host, ch->tx_ring[i]);
2134 }
2135
2136
2137 err_no_ring:
2138 kfree(ch->tx_ring);
2139 ch->tx_ring = NULL;
2140 kfree(ch->rx_ring);
2141 ch->rx_ring = NULL;
2142
2143 return -ENOMEM;
2144 }
2145
2146 static uint32_t srp_compute_rq_tmo(struct ib_qp_attr *qp_attr, int attr_mask)
2147 {
2148 uint64_t T_tr_ns, max_compl_time_ms;
2149 uint32_t rq_tmo_jiffies;
2150
2151 /*
2152 * According to section 11.2.4.2 in the IBTA spec (Modify Queue Pair,
2153 * table 91), both the QP timeout and the retry count have to be set
2154 * for RC QP's during the RTR to RTS transition.
2155 */
2156 WARN_ON_ONCE((attr_mask & (IB_QP_TIMEOUT | IB_QP_RETRY_CNT)) !=
2157 (IB_QP_TIMEOUT | IB_QP_RETRY_CNT));
2158
2159 /*
2160 * Set target->rq_tmo_jiffies to one second more than the largest time
2161 * it can take before an error completion is generated. See also
2162 * C9-140..142 in the IBTA spec for more information about how to
2163 * convert the QP Local ACK Timeout value to nanoseconds.
2164 */
2165 T_tr_ns = 4096 * (1ULL << qp_attr->timeout);
2166 max_compl_time_ms = qp_attr->retry_cnt * 4 * T_tr_ns;
2167 do_div(max_compl_time_ms, NSEC_PER_MSEC);
2168 rq_tmo_jiffies = msecs_to_jiffies(max_compl_time_ms + 1000);
2169
2170 return rq_tmo_jiffies;
2171 }
2172
2173 static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
2174 struct srp_login_rsp *lrsp,
2175 struct srp_rdma_ch *ch)
2176 {
2177 struct srp_target_port *target = ch->target;
2178 struct ib_qp_attr *qp_attr = NULL;
2179 int attr_mask = 0;
2180 int ret;
2181 int i;
2182
2183 if (lrsp->opcode == SRP_LOGIN_RSP) {
2184 ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
2185 ch->req_lim = be32_to_cpu(lrsp->req_lim_delta);
2186
2187 /*
2188 * Reserve credits for task management so we don't
2189 * bounce requests back to the SCSI mid-layer.
2190 */
2191 target->scsi_host->can_queue
2192 = min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2193 target->scsi_host->can_queue);
2194 target->scsi_host->cmd_per_lun
2195 = min_t(int, target->scsi_host->can_queue,
2196 target->scsi_host->cmd_per_lun);
2197 } else {
2198 shost_printk(KERN_WARNING, target->scsi_host,
2199 PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
2200 ret = -ECONNRESET;
2201 goto error;
2202 }
2203
2204 if (!ch->rx_ring) {
2205 ret = srp_alloc_iu_bufs(ch);
2206 if (ret)
2207 goto error;
2208 }
2209
2210 ret = -ENOMEM;
2211 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
2212 if (!qp_attr)
2213 goto error;
2214
2215 qp_attr->qp_state = IB_QPS_RTR;
2216 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
2217 if (ret)
2218 goto error_free;
2219
2220 ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2221 if (ret)
2222 goto error_free;
2223
2224 for (i = 0; i < target->queue_size; i++) {
2225 struct srp_iu *iu = ch->rx_ring[i];
2226
2227 ret = srp_post_recv(ch, iu);
2228 if (ret)
2229 goto error_free;
2230 }
2231
2232 qp_attr->qp_state = IB_QPS_RTS;
2233 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
2234 if (ret)
2235 goto error_free;
2236
2237 target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);
2238
2239 ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2240 if (ret)
2241 goto error_free;
2242
2243 ret = ib_send_cm_rtu(cm_id, NULL, 0);
2244
2245 error_free:
2246 kfree(qp_attr);
2247
2248 error:
2249 ch->status = ret;
2250 }
2251
2252 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
2253 struct ib_cm_event *event,
2254 struct srp_rdma_ch *ch)
2255 {
2256 struct srp_target_port *target = ch->target;
2257 struct Scsi_Host *shost = target->scsi_host;
2258 struct ib_class_port_info *cpi;
2259 int opcode;
2260
2261 switch (event->param.rej_rcvd.reason) {
2262 case IB_CM_REJ_PORT_CM_REDIRECT:
2263 cpi = event->param.rej_rcvd.ari;
2264 ch->path.dlid = cpi->redirect_lid;
2265 ch->path.pkey = cpi->redirect_pkey;
2266 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
2267 memcpy(ch->path.dgid.raw, cpi->redirect_gid, 16);
2268
2269 ch->status = ch->path.dlid ?
2270 SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
2271 break;
2272
2273 case IB_CM_REJ_PORT_REDIRECT:
2274 if (srp_target_is_topspin(target)) {
2275 /*
2276 * Topspin/Cisco SRP gateways incorrectly send
2277 * reject reason code 25 when they mean 24
2278 * (port redirect).
2279 */
2280 memcpy(ch->path.dgid.raw,
2281 event->param.rej_rcvd.ari, 16);
2282
2283 shost_printk(KERN_DEBUG, shost,
2284 PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
2285 be64_to_cpu(ch->path.dgid.global.subnet_prefix),
2286 be64_to_cpu(ch->path.dgid.global.interface_id));
2287
2288 ch->status = SRP_PORT_REDIRECT;
2289 } else {
2290 shost_printk(KERN_WARNING, shost,
2291 " REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2292 ch->status = -ECONNRESET;
2293 }
2294 break;
2295
2296 case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2297 shost_printk(KERN_WARNING, shost,
2298 " REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2299 ch->status = -ECONNRESET;
2300 break;
2301
2302 case IB_CM_REJ_CONSUMER_DEFINED:
2303 opcode = *(u8 *) event->private_data;
2304 if (opcode == SRP_LOGIN_REJ) {
2305 struct srp_login_rej *rej = event->private_data;
2306 u32 reason = be32_to_cpu(rej->reason);
2307
2308 if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
2309 shost_printk(KERN_WARNING, shost,
2310 PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2311 else
2312 shost_printk(KERN_WARNING, shost, PFX
2313 "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2314 target->sgid.raw,
2315 target->orig_dgid.raw, reason);
2316 } else
2317 shost_printk(KERN_WARNING, shost,
2318 " REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
2319 " opcode 0x%02x\n", opcode);
2320 ch->status = -ECONNRESET;
2321 break;
2322
2323 case IB_CM_REJ_STALE_CONN:
2324 shost_printk(KERN_WARNING, shost, " REJ reason: stale connection\n");
2325 ch->status = SRP_STALE_CONN;
2326 break;
2327
2328 default:
2329 shost_printk(KERN_WARNING, shost, " REJ reason 0x%x\n",
2330 event->param.rej_rcvd.reason);
2331 ch->status = -ECONNRESET;
2332 }
2333 }
2334
2335 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2336 {
2337 struct srp_rdma_ch *ch = cm_id->context;
2338 struct srp_target_port *target = ch->target;
2339 int comp = 0;
2340
2341 switch (event->event) {
2342 case IB_CM_REQ_ERROR:
2343 shost_printk(KERN_DEBUG, target->scsi_host,
2344 PFX "Sending CM REQ failed\n");
2345 comp = 1;
2346 ch->status = -ECONNRESET;
2347 break;
2348
2349 case IB_CM_REP_RECEIVED:
2350 comp = 1;
2351 srp_cm_rep_handler(cm_id, event->private_data, ch);
2352 break;
2353
2354 case IB_CM_REJ_RECEIVED:
2355 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2356 comp = 1;
2357
2358 srp_cm_rej_handler(cm_id, event, ch);
2359 break;
2360
2361 case IB_CM_DREQ_RECEIVED:
2362 shost_printk(KERN_WARNING, target->scsi_host,
2363 PFX "DREQ received - connection closed\n");
2364 ch->connected = false;
2365 if (ib_send_cm_drep(cm_id, NULL, 0))
2366 shost_printk(KERN_ERR, target->scsi_host,
2367 PFX "Sending CM DREP failed\n");
2368 queue_work(system_long_wq, &target->tl_err_work);
2369 break;
2370
2371 case IB_CM_TIMEWAIT_EXIT:
2372 shost_printk(KERN_ERR, target->scsi_host,
2373 PFX "connection closed\n");
2374 comp = 1;
2375
2376 ch->status = 0;
2377 break;
2378
2379 case IB_CM_MRA_RECEIVED:
2380 case IB_CM_DREQ_ERROR:
2381 case IB_CM_DREP_RECEIVED:
2382 break;
2383
2384 default:
2385 shost_printk(KERN_WARNING, target->scsi_host,
2386 PFX "Unhandled CM event %d\n", event->event);
2387 break;
2388 }
2389
2390 if (comp)
2391 complete(&ch->done);
2392
2393 return 0;
2394 }
2395
2396 /**
2397 * srp_change_queue_depth - setting device queue depth
2398 * @sdev: scsi device struct
2399 * @qdepth: requested queue depth
2400 *
2401 * Returns queue depth.
2402 */
2403 static int
2404 srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
2405 {
2406 if (!sdev->tagged_supported)
2407 qdepth = 1;
2408 return scsi_change_queue_depth(sdev, qdepth);
2409 }
2410
2411 static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag, u64 lun,
2412 u8 func)
2413 {
2414 struct srp_target_port *target = ch->target;
2415 struct srp_rport *rport = target->rport;
2416 struct ib_device *dev = target->srp_host->srp_dev->dev;
2417 struct srp_iu *iu;
2418 struct srp_tsk_mgmt *tsk_mgmt;
2419
2420 if (!ch->connected || target->qp_in_error)
2421 return -1;
2422
2423 init_completion(&ch->tsk_mgmt_done);
2424
2425 /*
2426 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2427 * invoked while a task management function is being sent.
2428 */
2429 mutex_lock(&rport->mutex);
2430 spin_lock_irq(&ch->lock);
2431 iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
2432 spin_unlock_irq(&ch->lock);
2433
2434 if (!iu) {
2435 mutex_unlock(&rport->mutex);
2436
2437 return -1;
2438 }
2439
2440 ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
2441 DMA_TO_DEVICE);
2442 tsk_mgmt = iu->buf;
2443 memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
2444
2445 tsk_mgmt->opcode = SRP_TSK_MGMT;
2446 int_to_scsilun(lun, &tsk_mgmt->lun);
2447 tsk_mgmt->tag = req_tag | SRP_TAG_TSK_MGMT;
2448 tsk_mgmt->tsk_mgmt_func = func;
2449 tsk_mgmt->task_tag = req_tag;
2450
2451 ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
2452 DMA_TO_DEVICE);
2453 if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
2454 srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2455 mutex_unlock(&rport->mutex);
2456
2457 return -1;
2458 }
2459 mutex_unlock(&rport->mutex);
2460
2461 if (!wait_for_completion_timeout(&ch->tsk_mgmt_done,
2462 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
2463 return -1;
2464
2465 return 0;
2466 }
2467
2468 static int srp_abort(struct scsi_cmnd *scmnd)
2469 {
2470 struct srp_target_port *target = host_to_target(scmnd->device->host);
2471 struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
2472 u32 tag;
2473 u16 ch_idx;
2474 struct srp_rdma_ch *ch;
2475 int ret;
2476
2477 shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2478
2479 if (!req)
2480 return SUCCESS;
2481 tag = blk_mq_unique_tag(scmnd->request);
2482 ch_idx = blk_mq_unique_tag_to_hwq(tag);
2483 if (WARN_ON_ONCE(ch_idx >= target->ch_count))
2484 return SUCCESS;
2485 ch = &target->ch[ch_idx];
2486 if (!srp_claim_req(ch, req, NULL, scmnd))
2487 return SUCCESS;
2488 shost_printk(KERN_ERR, target->scsi_host,
2489 "Sending SRP abort for tag %#x\n", tag);
2490 if (srp_send_tsk_mgmt(ch, tag, scmnd->device->lun,
2491 SRP_TSK_ABORT_TASK) == 0)
2492 ret = SUCCESS;
2493 else if (target->rport->state == SRP_RPORT_LOST)
2494 ret = FAST_IO_FAIL;
2495 else
2496 ret = FAILED;
2497 srp_free_req(ch, req, scmnd, 0);
2498 scmnd->result = DID_ABORT << 16;
2499 scmnd->scsi_done(scmnd);
2500
2501 return ret;
2502 }
2503
2504 static int srp_reset_device(struct scsi_cmnd *scmnd)
2505 {
2506 struct srp_target_port *target = host_to_target(scmnd->device->host);
2507 struct srp_rdma_ch *ch;
2508 int i;
2509
2510 shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2511
2512 ch = &target->ch[0];
2513 if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2514 SRP_TSK_LUN_RESET))
2515 return FAILED;
2516 if (ch->tsk_mgmt_status)
2517 return FAILED;
2518
2519 for (i = 0; i < target->ch_count; i++) {
2520 ch = &target->ch[i];
2521 for (i = 0; i < target->req_ring_size; ++i) {
2522 struct srp_request *req = &ch->req_ring[i];
2523
2524 srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
2525 }
2526 }
2527
2528 return SUCCESS;
2529 }
2530
2531 static int srp_reset_host(struct scsi_cmnd *scmnd)
2532 {
2533 struct srp_target_port *target = host_to_target(scmnd->device->host);
2534
2535 shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
2536
2537 return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
2538 }
2539
2540 static int srp_slave_configure(struct scsi_device *sdev)
2541 {
2542 struct Scsi_Host *shost = sdev->host;
2543 struct srp_target_port *target = host_to_target(shost);
2544 struct request_queue *q = sdev->request_queue;
2545 unsigned long timeout;
2546
2547 if (sdev->type == TYPE_DISK) {
2548 timeout = max_t(unsigned, 30 * HZ, target->rq_tmo_jiffies);
2549 blk_queue_rq_timeout(q, timeout);
2550 }
2551
2552 return 0;
2553 }
2554
2555 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
2556 char *buf)
2557 {
2558 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2559
2560 return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->id_ext));
2561 }
2562
2563 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
2564 char *buf)
2565 {
2566 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2567
2568 return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->ioc_guid));
2569 }
2570
2571 static ssize_t show_service_id(struct device *dev,
2572 struct device_attribute *attr, char *buf)
2573 {
2574 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2575
2576 return sprintf(buf, "0x%016llx\n", be64_to_cpu(target->service_id));
2577 }
2578
2579 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
2580 char *buf)
2581 {
2582 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2583
2584 return sprintf(buf, "0x%04x\n", be16_to_cpu(target->pkey));
2585 }
2586
2587 static ssize_t show_sgid(struct device *dev, struct device_attribute *attr,
2588 char *buf)
2589 {
2590 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2591
2592 return sprintf(buf, "%pI6\n", target->sgid.raw);
2593 }
2594
2595 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
2596 char *buf)
2597 {
2598 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2599 struct srp_rdma_ch *ch = &target->ch[0];
2600
2601 return sprintf(buf, "%pI6\n", ch->path.dgid.raw);
2602 }
2603
2604 static ssize_t show_orig_dgid(struct device *dev,
2605 struct device_attribute *attr, char *buf)
2606 {
2607 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2608
2609 return sprintf(buf, "%pI6\n", target->orig_dgid.raw);
2610 }
2611
2612 static ssize_t show_req_lim(struct device *dev,
2613 struct device_attribute *attr, char *buf)
2614 {
2615 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2616 struct srp_rdma_ch *ch;
2617 int i, req_lim = INT_MAX;
2618
2619 for (i = 0; i < target->ch_count; i++) {
2620 ch = &target->ch[i];
2621 req_lim = min(req_lim, ch->req_lim);
2622 }
2623 return sprintf(buf, "%d\n", req_lim);
2624 }
2625
2626 static ssize_t show_zero_req_lim(struct device *dev,
2627 struct device_attribute *attr, char *buf)
2628 {
2629 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2630
2631 return sprintf(buf, "%d\n", target->zero_req_lim);
2632 }
2633
2634 static ssize_t show_local_ib_port(struct device *dev,
2635 struct device_attribute *attr, char *buf)
2636 {
2637 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2638
2639 return sprintf(buf, "%d\n", target->srp_host->port);
2640 }
2641
2642 static ssize_t show_local_ib_device(struct device *dev,
2643 struct device_attribute *attr, char *buf)
2644 {
2645 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2646
2647 return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
2648 }
2649
2650 static ssize_t show_ch_count(struct device *dev, struct device_attribute *attr,
2651 char *buf)
2652 {
2653 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2654
2655 return sprintf(buf, "%d\n", target->ch_count);
2656 }
2657
2658 static ssize_t show_comp_vector(struct device *dev,
2659 struct device_attribute *attr, char *buf)
2660 {
2661 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2662
2663 return sprintf(buf, "%d\n", target->comp_vector);
2664 }
2665
2666 static ssize_t show_tl_retry_count(struct device *dev,
2667 struct device_attribute *attr, char *buf)
2668 {
2669 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2670
2671 return sprintf(buf, "%d\n", target->tl_retry_count);
2672 }
2673
2674 static ssize_t show_cmd_sg_entries(struct device *dev,
2675 struct device_attribute *attr, char *buf)
2676 {
2677 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2678
2679 return sprintf(buf, "%u\n", target->cmd_sg_cnt);
2680 }
2681
2682 static ssize_t show_allow_ext_sg(struct device *dev,
2683 struct device_attribute *attr, char *buf)
2684 {
2685 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2686
2687 return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
2688 }
2689
2690 static DEVICE_ATTR(id_ext, S_IRUGO, show_id_ext, NULL);
2691 static DEVICE_ATTR(ioc_guid, S_IRUGO, show_ioc_guid, NULL);
2692 static DEVICE_ATTR(service_id, S_IRUGO, show_service_id, NULL);
2693 static DEVICE_ATTR(pkey, S_IRUGO, show_pkey, NULL);
2694 static DEVICE_ATTR(sgid, S_IRUGO, show_sgid, NULL);
2695 static DEVICE_ATTR(dgid, S_IRUGO, show_dgid, NULL);
2696 static DEVICE_ATTR(orig_dgid, S_IRUGO, show_orig_dgid, NULL);
2697 static DEVICE_ATTR(req_lim, S_IRUGO, show_req_lim, NULL);
2698 static DEVICE_ATTR(zero_req_lim, S_IRUGO, show_zero_req_lim, NULL);
2699 static DEVICE_ATTR(local_ib_port, S_IRUGO, show_local_ib_port, NULL);
2700 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
2701 static DEVICE_ATTR(ch_count, S_IRUGO, show_ch_count, NULL);
2702 static DEVICE_ATTR(comp_vector, S_IRUGO, show_comp_vector, NULL);
2703 static DEVICE_ATTR(tl_retry_count, S_IRUGO, show_tl_retry_count, NULL);
2704 static DEVICE_ATTR(cmd_sg_entries, S_IRUGO, show_cmd_sg_entries, NULL);
2705 static DEVICE_ATTR(allow_ext_sg, S_IRUGO, show_allow_ext_sg, NULL);
2706
2707 static struct device_attribute *srp_host_attrs[] = {
2708 &dev_attr_id_ext,
2709 &dev_attr_ioc_guid,
2710 &dev_attr_service_id,
2711 &dev_attr_pkey,
2712 &dev_attr_sgid,
2713 &dev_attr_dgid,
2714 &dev_attr_orig_dgid,
2715 &dev_attr_req_lim,
2716 &dev_attr_zero_req_lim,
2717 &dev_attr_local_ib_port,
2718 &dev_attr_local_ib_device,
2719 &dev_attr_ch_count,
2720 &dev_attr_comp_vector,
2721 &dev_attr_tl_retry_count,
2722 &dev_attr_cmd_sg_entries,
2723 &dev_attr_allow_ext_sg,
2724 NULL
2725 };
2726
2727 static struct scsi_host_template srp_template = {
2728 .module = THIS_MODULE,
2729 .name = "InfiniBand SRP initiator",
2730 .proc_name = DRV_NAME,
2731 .slave_configure = srp_slave_configure,
2732 .info = srp_target_info,
2733 .queuecommand = srp_queuecommand,
2734 .change_queue_depth = srp_change_queue_depth,
2735 .eh_abort_handler = srp_abort,
2736 .eh_device_reset_handler = srp_reset_device,
2737 .eh_host_reset_handler = srp_reset_host,
2738 .skip_settle_delay = true,
2739 .sg_tablesize = SRP_DEF_SG_TABLESIZE,
2740 .can_queue = SRP_DEFAULT_CMD_SQ_SIZE,
2741 .this_id = -1,
2742 .cmd_per_lun = SRP_DEFAULT_CMD_SQ_SIZE,
2743 .use_clustering = ENABLE_CLUSTERING,
2744 .shost_attrs = srp_host_attrs,
2745 .use_blk_tags = 1,
2746 .track_queue_depth = 1,
2747 };
2748
2749 static int srp_sdev_count(struct Scsi_Host *host)
2750 {
2751 struct scsi_device *sdev;
2752 int c = 0;
2753
2754 shost_for_each_device(sdev, host)
2755 c++;
2756
2757 return c;
2758 }
2759
2760 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
2761 {
2762 struct srp_rport_identifiers ids;
2763 struct srp_rport *rport;
2764
2765 target->state = SRP_TARGET_SCANNING;
2766 sprintf(target->target_name, "SRP.T10:%016llX",
2767 be64_to_cpu(target->id_ext));
2768
2769 if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
2770 return -ENODEV;
2771
2772 memcpy(ids.port_id, &target->id_ext, 8);
2773 memcpy(ids.port_id + 8, &target->ioc_guid, 8);
2774 ids.roles = SRP_RPORT_ROLE_TARGET;
2775 rport = srp_rport_add(target->scsi_host, &ids);
2776 if (IS_ERR(rport)) {
2777 scsi_remove_host(target->scsi_host);
2778 return PTR_ERR(rport);
2779 }
2780
2781 rport->lld_data = target;
2782 target->rport = rport;
2783
2784 spin_lock(&host->target_lock);
2785 list_add_tail(&target->list, &host->target_list);
2786 spin_unlock(&host->target_lock);
2787
2788 scsi_scan_target(&target->scsi_host->shost_gendev,
2789 0, target->scsi_id, SCAN_WILD_CARD, 0);
2790
2791 if (srp_connected_ch(target) < target->ch_count ||
2792 target->qp_in_error) {
2793 shost_printk(KERN_INFO, target->scsi_host,
2794 PFX "SCSI scan failed - removing SCSI host\n");
2795 srp_queue_remove_work(target);
2796 goto out;
2797 }
2798
2799 pr_debug(PFX "%s: SCSI scan succeeded - detected %d LUNs\n",
2800 dev_name(&target->scsi_host->shost_gendev),
2801 srp_sdev_count(target->scsi_host));
2802
2803 spin_lock_irq(&target->lock);
2804 if (target->state == SRP_TARGET_SCANNING)
2805 target->state = SRP_TARGET_LIVE;
2806 spin_unlock_irq(&target->lock);
2807
2808 out:
2809 return 0;
2810 }
2811
2812 static void srp_release_dev(struct device *dev)
2813 {
2814 struct srp_host *host =
2815 container_of(dev, struct srp_host, dev);
2816
2817 complete(&host->released);
2818 }
2819
2820 static struct class srp_class = {
2821 .name = "infiniband_srp",
2822 .dev_release = srp_release_dev
2823 };
2824
2825 /**
2826 * srp_conn_unique() - check whether the connection to a target is unique
2827 * @host: SRP host.
2828 * @target: SRP target port.
2829 */
2830 static bool srp_conn_unique(struct srp_host *host,
2831 struct srp_target_port *target)
2832 {
2833 struct srp_target_port *t;
2834 bool ret = false;
2835
2836 if (target->state == SRP_TARGET_REMOVED)
2837 goto out;
2838
2839 ret = true;
2840
2841 spin_lock(&host->target_lock);
2842 list_for_each_entry(t, &host->target_list, list) {
2843 if (t != target &&
2844 target->id_ext == t->id_ext &&
2845 target->ioc_guid == t->ioc_guid &&
2846 target->initiator_ext == t->initiator_ext) {
2847 ret = false;
2848 break;
2849 }
2850 }
2851 spin_unlock(&host->target_lock);
2852
2853 out:
2854 return ret;
2855 }
2856
2857 /*
2858 * Target ports are added by writing
2859 *
2860 * id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
2861 * pkey=<P_Key>,service_id=<service ID>
2862 *
2863 * to the add_target sysfs attribute.
2864 */
2865 enum {
2866 SRP_OPT_ERR = 0,
2867 SRP_OPT_ID_EXT = 1 << 0,
2868 SRP_OPT_IOC_GUID = 1 << 1,
2869 SRP_OPT_DGID = 1 << 2,
2870 SRP_OPT_PKEY = 1 << 3,
2871 SRP_OPT_SERVICE_ID = 1 << 4,
2872 SRP_OPT_MAX_SECT = 1 << 5,
2873 SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
2874 SRP_OPT_IO_CLASS = 1 << 7,
2875 SRP_OPT_INITIATOR_EXT = 1 << 8,
2876 SRP_OPT_CMD_SG_ENTRIES = 1 << 9,
2877 SRP_OPT_ALLOW_EXT_SG = 1 << 10,
2878 SRP_OPT_SG_TABLESIZE = 1 << 11,
2879 SRP_OPT_COMP_VECTOR = 1 << 12,
2880 SRP_OPT_TL_RETRY_COUNT = 1 << 13,
2881 SRP_OPT_QUEUE_SIZE = 1 << 14,
2882 SRP_OPT_ALL = (SRP_OPT_ID_EXT |
2883 SRP_OPT_IOC_GUID |
2884 SRP_OPT_DGID |
2885 SRP_OPT_PKEY |
2886 SRP_OPT_SERVICE_ID),
2887 };
2888
2889 static const match_table_t srp_opt_tokens = {
2890 { SRP_OPT_ID_EXT, "id_ext=%s" },
2891 { SRP_OPT_IOC_GUID, "ioc_guid=%s" },
2892 { SRP_OPT_DGID, "dgid=%s" },
2893 { SRP_OPT_PKEY, "pkey=%x" },
2894 { SRP_OPT_SERVICE_ID, "service_id=%s" },
2895 { SRP_OPT_MAX_SECT, "max_sect=%d" },
2896 { SRP_OPT_MAX_CMD_PER_LUN, "max_cmd_per_lun=%d" },
2897 { SRP_OPT_IO_CLASS, "io_class=%x" },
2898 { SRP_OPT_INITIATOR_EXT, "initiator_ext=%s" },
2899 { SRP_OPT_CMD_SG_ENTRIES, "cmd_sg_entries=%u" },
2900 { SRP_OPT_ALLOW_EXT_SG, "allow_ext_sg=%u" },
2901 { SRP_OPT_SG_TABLESIZE, "sg_tablesize=%u" },
2902 { SRP_OPT_COMP_VECTOR, "comp_vector=%u" },
2903 { SRP_OPT_TL_RETRY_COUNT, "tl_retry_count=%u" },
2904 { SRP_OPT_QUEUE_SIZE, "queue_size=%d" },
2905 { SRP_OPT_ERR, NULL }
2906 };
2907
2908 static int srp_parse_options(const char *buf, struct srp_target_port *target)
2909 {
2910 char *options, *sep_opt;
2911 char *p;
2912 char dgid[3];
2913 substring_t args[MAX_OPT_ARGS];
2914 int opt_mask = 0;
2915 int token;
2916 int ret = -EINVAL;
2917 int i;
2918
2919 options = kstrdup(buf, GFP_KERNEL);
2920 if (!options)
2921 return -ENOMEM;
2922
2923 sep_opt = options;
2924 while ((p = strsep(&sep_opt, ",\n")) != NULL) {
2925 if (!*p)
2926 continue;
2927
2928 token = match_token(p, srp_opt_tokens, args);
2929 opt_mask |= token;
2930
2931 switch (token) {
2932 case SRP_OPT_ID_EXT:
2933 p = match_strdup(args);
2934 if (!p) {
2935 ret = -ENOMEM;
2936 goto out;
2937 }
2938 target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
2939 kfree(p);
2940 break;
2941
2942 case SRP_OPT_IOC_GUID:
2943 p = match_strdup(args);
2944 if (!p) {
2945 ret = -ENOMEM;
2946 goto out;
2947 }
2948 target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
2949 kfree(p);
2950 break;
2951
2952 case SRP_OPT_DGID:
2953 p = match_strdup(args);
2954 if (!p) {
2955 ret = -ENOMEM;
2956 goto out;
2957 }
2958 if (strlen(p) != 32) {
2959 pr_warn("bad dest GID parameter '%s'\n", p);
2960 kfree(p);
2961 goto out;
2962 }
2963
2964 for (i = 0; i < 16; ++i) {
2965 strlcpy(dgid, p + i * 2, sizeof(dgid));
2966 if (sscanf(dgid, "%hhx",
2967 &target->orig_dgid.raw[i]) < 1) {
2968 ret = -EINVAL;
2969 kfree(p);
2970 goto out;
2971 }
2972 }
2973 kfree(p);
2974 break;
2975
2976 case SRP_OPT_PKEY:
2977 if (match_hex(args, &token)) {
2978 pr_warn("bad P_Key parameter '%s'\n", p);
2979 goto out;
2980 }
2981 target->pkey = cpu_to_be16(token);
2982 break;
2983
2984 case SRP_OPT_SERVICE_ID:
2985 p = match_strdup(args);
2986 if (!p) {
2987 ret = -ENOMEM;
2988 goto out;
2989 }
2990 target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
2991 kfree(p);
2992 break;
2993
2994 case SRP_OPT_MAX_SECT:
2995 if (match_int(args, &token)) {
2996 pr_warn("bad max sect parameter '%s'\n", p);
2997 goto out;
2998 }
2999 target->scsi_host->max_sectors = token;
3000 break;
3001
3002 case SRP_OPT_QUEUE_SIZE:
3003 if (match_int(args, &token) || token < 1) {
3004 pr_warn("bad queue_size parameter '%s'\n", p);
3005 goto out;
3006 }
3007 target->scsi_host->can_queue = token;
3008 target->queue_size = token + SRP_RSP_SQ_SIZE +
3009 SRP_TSK_MGMT_SQ_SIZE;
3010 if (!(opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
3011 target->scsi_host->cmd_per_lun = token;
3012 break;
3013
3014 case SRP_OPT_MAX_CMD_PER_LUN:
3015 if (match_int(args, &token) || token < 1) {
3016 pr_warn("bad max cmd_per_lun parameter '%s'\n",
3017 p);
3018 goto out;
3019 }
3020 target->scsi_host->cmd_per_lun = token;
3021 break;
3022
3023 case SRP_OPT_IO_CLASS:
3024 if (match_hex(args, &token)) {
3025 pr_warn("bad IO class parameter '%s'\n", p);
3026 goto out;
3027 }
3028 if (token != SRP_REV10_IB_IO_CLASS &&
3029 token != SRP_REV16A_IB_IO_CLASS) {
3030 pr_warn("unknown IO class parameter value %x specified (use %x or %x).\n",
3031 token, SRP_REV10_IB_IO_CLASS,
3032 SRP_REV16A_IB_IO_CLASS);
3033 goto out;
3034 }
3035 target->io_class = token;
3036 break;
3037
3038 case SRP_OPT_INITIATOR_EXT:
3039 p = match_strdup(args);
3040 if (!p) {
3041 ret = -ENOMEM;
3042 goto out;
3043 }
3044 target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
3045 kfree(p);
3046 break;
3047
3048 case SRP_OPT_CMD_SG_ENTRIES:
3049 if (match_int(args, &token) || token < 1 || token > 255) {
3050 pr_warn("bad max cmd_sg_entries parameter '%s'\n",
3051 p);
3052 goto out;
3053 }
3054 target->cmd_sg_cnt = token;
3055 break;
3056
3057 case SRP_OPT_ALLOW_EXT_SG:
3058 if (match_int(args, &token)) {
3059 pr_warn("bad allow_ext_sg parameter '%s'\n", p);
3060 goto out;
3061 }
3062 target->allow_ext_sg = !!token;
3063 break;
3064
3065 case SRP_OPT_SG_TABLESIZE:
3066 if (match_int(args, &token) || token < 1 ||
3067 token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
3068 pr_warn("bad max sg_tablesize parameter '%s'\n",
3069 p);
3070 goto out;
3071 }
3072 target->sg_tablesize = token;
3073 break;
3074
3075 case SRP_OPT_COMP_VECTOR:
3076 if (match_int(args, &token) || token < 0) {
3077 pr_warn("bad comp_vector parameter '%s'\n", p);
3078 goto out;
3079 }
3080 target->comp_vector = token;
3081 break;
3082
3083 case SRP_OPT_TL_RETRY_COUNT:
3084 if (match_int(args, &token) || token < 2 || token > 7) {
3085 pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n",
3086 p);
3087 goto out;
3088 }
3089 target->tl_retry_count = token;
3090 break;
3091
3092 default:
3093 pr_warn("unknown parameter or missing value '%s' in target creation request\n",
3094 p);
3095 goto out;
3096 }
3097 }
3098
3099 if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
3100 ret = 0;
3101 else
3102 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
3103 if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
3104 !(srp_opt_tokens[i].token & opt_mask))
3105 pr_warn("target creation request is missing parameter '%s'\n",
3106 srp_opt_tokens[i].pattern);
3107
3108 if (target->scsi_host->cmd_per_lun > target->scsi_host->can_queue
3109 && (opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
3110 pr_warn("cmd_per_lun = %d > queue_size = %d\n",
3111 target->scsi_host->cmd_per_lun,
3112 target->scsi_host->can_queue);
3113
3114 out:
3115 kfree(options);
3116 return ret;
3117 }
3118
3119 static ssize_t srp_create_target(struct device *dev,
3120 struct device_attribute *attr,
3121 const char *buf, size_t count)
3122 {
3123 struct srp_host *host =
3124 container_of(dev, struct srp_host, dev);
3125 struct Scsi_Host *target_host;
3126 struct srp_target_port *target;
3127 struct srp_rdma_ch *ch;
3128 struct srp_device *srp_dev = host->srp_dev;
3129 struct ib_device *ibdev = srp_dev->dev;
3130 int ret, node_idx, node, cpu, i;
3131 bool multich = false;
3132
3133 target_host = scsi_host_alloc(&srp_template,
3134 sizeof (struct srp_target_port));
3135 if (!target_host)
3136 return -ENOMEM;
3137
3138 target_host->transportt = ib_srp_transport_template;
3139 target_host->max_channel = 0;
3140 target_host->max_id = 1;
3141 target_host->max_lun = -1LL;
3142 target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
3143
3144 target = host_to_target(target_host);
3145
3146 target->io_class = SRP_REV16A_IB_IO_CLASS;
3147 target->scsi_host = target_host;
3148 target->srp_host = host;
3149 target->lkey = host->srp_dev->mr->lkey;
3150 target->rkey = host->srp_dev->mr->rkey;
3151 target->cmd_sg_cnt = cmd_sg_entries;
3152 target->sg_tablesize = indirect_sg_entries ? : cmd_sg_entries;
3153 target->allow_ext_sg = allow_ext_sg;
3154 target->tl_retry_count = 7;
3155 target->queue_size = SRP_DEFAULT_QUEUE_SIZE;
3156
3157 /*
3158 * Avoid that the SCSI host can be removed by srp_remove_target()
3159 * before this function returns.
3160 */
3161 scsi_host_get(target->scsi_host);
3162
3163 mutex_lock(&host->add_target_mutex);
3164
3165 ret = srp_parse_options(buf, target);
3166 if (ret)
3167 goto out;
3168
3169 ret = scsi_init_shared_tag_map(target_host, target_host->can_queue);
3170 if (ret)
3171 goto out;
3172
3173 target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;
3174
3175 if (!srp_conn_unique(target->srp_host, target)) {
3176 shost_printk(KERN_INFO, target->scsi_host,
3177 PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;initiator_ext=%016llx\n",
3178 be64_to_cpu(target->id_ext),
3179 be64_to_cpu(target->ioc_guid),
3180 be64_to_cpu(target->initiator_ext));
3181 ret = -EEXIST;
3182 goto out;
3183 }
3184
3185 if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3186 target->cmd_sg_cnt < target->sg_tablesize) {
3187 pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3188 target->sg_tablesize = target->cmd_sg_cnt;
3189 }
3190
3191 target_host->sg_tablesize = target->sg_tablesize;
3192 target->indirect_size = target->sg_tablesize *
3193 sizeof (struct srp_direct_buf);
3194 target->max_iu_len = sizeof (struct srp_cmd) +
3195 sizeof (struct srp_indirect_buf) +
3196 target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
3197
3198 INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3199 INIT_WORK(&target->remove_work, srp_remove_work);
3200 spin_lock_init(&target->lock);
3201 ret = ib_query_gid(ibdev, host->port, 0, &target->sgid);
3202 if (ret)
3203 goto out;
3204
3205 ret = -ENOMEM;
3206 target->ch_count = max_t(unsigned, num_online_nodes(),
3207 min(ch_count ? :
3208 min(4 * num_online_nodes(),
3209 ibdev->num_comp_vectors),
3210 num_online_cpus()));
3211 target->ch = kcalloc(target->ch_count, sizeof(*target->ch),
3212 GFP_KERNEL);
3213 if (!target->ch)
3214 goto out;
3215
3216 node_idx = 0;
3217 for_each_online_node(node) {
3218 const int ch_start = (node_idx * target->ch_count /
3219 num_online_nodes());
3220 const int ch_end = ((node_idx + 1) * target->ch_count /
3221 num_online_nodes());
3222 const int cv_start = (node_idx * ibdev->num_comp_vectors /
3223 num_online_nodes() + target->comp_vector)
3224 % ibdev->num_comp_vectors;
3225 const int cv_end = ((node_idx + 1) * ibdev->num_comp_vectors /
3226 num_online_nodes() + target->comp_vector)
3227 % ibdev->num_comp_vectors;
3228 int cpu_idx = 0;
3229
3230 for_each_online_cpu(cpu) {
3231 if (cpu_to_node(cpu) != node)
3232 continue;
3233 if (ch_start + cpu_idx >= ch_end)
3234 continue;
3235 ch = &target->ch[ch_start + cpu_idx];
3236 ch->target = target;
3237 ch->comp_vector = cv_start == cv_end ? cv_start :
3238 cv_start + cpu_idx % (cv_end - cv_start);
3239 spin_lock_init(&ch->lock);
3240 INIT_LIST_HEAD(&ch->free_tx);
3241 ret = srp_new_cm_id(ch);
3242 if (ret)
3243 goto err_disconnect;
3244
3245 ret = srp_create_ch_ib(ch);
3246 if (ret)
3247 goto err_disconnect;
3248
3249 ret = srp_alloc_req_data(ch);
3250 if (ret)
3251 goto err_disconnect;
3252
3253 ret = srp_connect_ch(ch, multich);
3254 if (ret) {
3255 shost_printk(KERN_ERR, target->scsi_host,
3256 PFX "Connection %d/%d failed\n",
3257 ch_start + cpu_idx,
3258 target->ch_count);
3259 if (node_idx == 0 && cpu_idx == 0) {
3260 goto err_disconnect;
3261 } else {
3262 srp_free_ch_ib(target, ch);
3263 srp_free_req_data(target, ch);
3264 target->ch_count = ch - target->ch;
3265 break;
3266 }
3267 }
3268
3269 multich = true;
3270 cpu_idx++;
3271 }
3272 node_idx++;
3273 }
3274
3275 target->scsi_host->nr_hw_queues = target->ch_count;
3276
3277 ret = srp_add_target(host, target);
3278 if (ret)
3279 goto err_disconnect;
3280
3281 if (target->state != SRP_TARGET_REMOVED) {
3282 shost_printk(KERN_DEBUG, target->scsi_host, PFX
3283 "new target: id_ext %016llx ioc_guid %016llx pkey %04x service_id %016llx sgid %pI6 dgid %pI6\n",
3284 be64_to_cpu(target->id_ext),
3285 be64_to_cpu(target->ioc_guid),
3286 be16_to_cpu(target->pkey),
3287 be64_to_cpu(target->service_id),
3288 target->sgid.raw, target->orig_dgid.raw);
3289 }
3290
3291 ret = count;
3292
3293 out:
3294 mutex_unlock(&host->add_target_mutex);
3295
3296 scsi_host_put(target->scsi_host);
3297
3298 return ret;
3299
3300 err_disconnect:
3301 srp_disconnect_target(target);
3302
3303 for (i = 0; i < target->ch_count; i++) {
3304 ch = &target->ch[i];
3305 srp_free_ch_ib(target, ch);
3306 srp_free_req_data(target, ch);
3307 }
3308
3309 kfree(target->ch);
3310 goto out;
3311 }
3312
3313 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3314
3315 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
3316 char *buf)
3317 {
3318 struct srp_host *host = container_of(dev, struct srp_host, dev);
3319
3320 return sprintf(buf, "%s\n", host->srp_dev->dev->name);
3321 }
3322
3323 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
3324
3325 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
3326 char *buf)
3327 {
3328 struct srp_host *host = container_of(dev, struct srp_host, dev);
3329
3330 return sprintf(buf, "%d\n", host->port);
3331 }
3332
3333 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
3334
3335 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
3336 {
3337 struct srp_host *host;
3338
3339 host = kzalloc(sizeof *host, GFP_KERNEL);
3340 if (!host)
3341 return NULL;
3342
3343 INIT_LIST_HEAD(&host->target_list);
3344 spin_lock_init(&host->target_lock);
3345 init_completion(&host->released);
3346 mutex_init(&host->add_target_mutex);
3347 host->srp_dev = device;
3348 host->port = port;
3349
3350 host->dev.class = &srp_class;
3351 host->dev.parent = device->dev->dma_device;
3352 dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
3353
3354 if (device_register(&host->dev))
3355 goto free_host;
3356 if (device_create_file(&host->dev, &dev_attr_add_target))
3357 goto err_class;
3358 if (device_create_file(&host->dev, &dev_attr_ibdev))
3359 goto err_class;
3360 if (device_create_file(&host->dev, &dev_attr_port))
3361 goto err_class;
3362
3363 return host;
3364
3365 err_class:
3366 device_unregister(&host->dev);
3367
3368 free_host:
3369 kfree(host);
3370
3371 return NULL;
3372 }
3373
3374 static void srp_add_one(struct ib_device *device)
3375 {
3376 struct srp_device *srp_dev;
3377 struct ib_device_attr *dev_attr;
3378 struct srp_host *host;
3379 int mr_page_shift, p;
3380 u64 max_pages_per_mr;
3381
3382 dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
3383 if (!dev_attr)
3384 return;
3385
3386 if (ib_query_device(device, dev_attr)) {
3387 pr_warn("Query device failed for %s\n", device->name);
3388 goto free_attr;
3389 }
3390
3391 srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
3392 if (!srp_dev)
3393 goto free_attr;
3394
3395 srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
3396 device->map_phys_fmr && device->unmap_fmr);
3397 srp_dev->has_fr = (dev_attr->device_cap_flags &
3398 IB_DEVICE_MEM_MGT_EXTENSIONS);
3399 if (!srp_dev->has_fmr && !srp_dev->has_fr)
3400 dev_warn(&device->dev, "neither FMR nor FR is supported\n");
3401
3402 srp_dev->use_fast_reg = (srp_dev->has_fr &&
3403 (!srp_dev->has_fmr || prefer_fr));
3404
3405 /*
3406 * Use the smallest page size supported by the HCA, down to a
3407 * minimum of 4096 bytes. We're unlikely to build large sglists
3408 * out of smaller entries.
3409 */
3410 mr_page_shift = max(12, ffs(dev_attr->page_size_cap) - 1);
3411 srp_dev->mr_page_size = 1 << mr_page_shift;
3412 srp_dev->mr_page_mask = ~((u64) srp_dev->mr_page_size - 1);
3413 max_pages_per_mr = dev_attr->max_mr_size;
3414 do_div(max_pages_per_mr, srp_dev->mr_page_size);
3415 srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
3416 max_pages_per_mr);
3417 if (srp_dev->use_fast_reg) {
3418 srp_dev->max_pages_per_mr =
3419 min_t(u32, srp_dev->max_pages_per_mr,
3420 dev_attr->max_fast_reg_page_list_len);
3421 }
3422 srp_dev->mr_max_size = srp_dev->mr_page_size *
3423 srp_dev->max_pages_per_mr;
3424 pr_debug("%s: mr_page_shift = %d, dev_attr->max_mr_size = %#llx, dev_attr->max_fast_reg_page_list_len = %u, max_pages_per_mr = %d, mr_max_size = %#x\n",
3425 device->name, mr_page_shift, dev_attr->max_mr_size,
3426 dev_attr->max_fast_reg_page_list_len,
3427 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
3428
3429 INIT_LIST_HEAD(&srp_dev->dev_list);
3430
3431 srp_dev->dev = device;
3432 srp_dev->pd = ib_alloc_pd(device);
3433 if (IS_ERR(srp_dev->pd))
3434 goto free_dev;
3435
3436 srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
3437 IB_ACCESS_LOCAL_WRITE |
3438 IB_ACCESS_REMOTE_READ |
3439 IB_ACCESS_REMOTE_WRITE);
3440 if (IS_ERR(srp_dev->mr))
3441 goto err_pd;
3442
3443 for (p = rdma_start_port(device); p <= rdma_end_port(device); ++p) {
3444 host = srp_add_port(srp_dev, p);
3445 if (host)
3446 list_add_tail(&host->list, &srp_dev->dev_list);
3447 }
3448
3449 ib_set_client_data(device, &srp_client, srp_dev);
3450
3451 goto free_attr;
3452
3453 err_pd:
3454 ib_dealloc_pd(srp_dev->pd);
3455
3456 free_dev:
3457 kfree(srp_dev);
3458
3459 free_attr:
3460 kfree(dev_attr);
3461 }
3462
3463 static void srp_remove_one(struct ib_device *device)
3464 {
3465 struct srp_device *srp_dev;
3466 struct srp_host *host, *tmp_host;
3467 struct srp_target_port *target;
3468
3469 srp_dev = ib_get_client_data(device, &srp_client);
3470 if (!srp_dev)
3471 return;
3472
3473 list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
3474 device_unregister(&host->dev);
3475 /*
3476 * Wait for the sysfs entry to go away, so that no new
3477 * target ports can be created.
3478 */
3479 wait_for_completion(&host->released);
3480
3481 /*
3482 * Remove all target ports.
3483 */
3484 spin_lock(&host->target_lock);
3485 list_for_each_entry(target, &host->target_list, list)
3486 srp_queue_remove_work(target);
3487 spin_unlock(&host->target_lock);
3488
3489 /*
3490 * Wait for tl_err and target port removal tasks.
3491 */
3492 flush_workqueue(system_long_wq);
3493 flush_workqueue(srp_remove_wq);
3494
3495 kfree(host);
3496 }
3497
3498 ib_dereg_mr(srp_dev->mr);
3499 ib_dealloc_pd(srp_dev->pd);
3500
3501 kfree(srp_dev);
3502 }
3503
3504 static struct srp_function_template ib_srp_transport_functions = {
3505 .has_rport_state = true,
3506 .reset_timer_if_blocked = true,
3507 .reconnect_delay = &srp_reconnect_delay,
3508 .fast_io_fail_tmo = &srp_fast_io_fail_tmo,
3509 .dev_loss_tmo = &srp_dev_loss_tmo,
3510 .reconnect = srp_rport_reconnect,
3511 .rport_delete = srp_rport_delete,
3512 .terminate_rport_io = srp_terminate_io,
3513 };
3514
3515 static int __init srp_init_module(void)
3516 {
3517 int ret;
3518
3519 BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
3520
3521 if (srp_sg_tablesize) {
3522 pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
3523 if (!cmd_sg_entries)
3524 cmd_sg_entries = srp_sg_tablesize;
3525 }
3526
3527 if (!cmd_sg_entries)
3528 cmd_sg_entries = SRP_DEF_SG_TABLESIZE;
3529
3530 if (cmd_sg_entries > 255) {
3531 pr_warn("Clamping cmd_sg_entries to 255\n");
3532 cmd_sg_entries = 255;
3533 }
3534
3535 if (!indirect_sg_entries)
3536 indirect_sg_entries = cmd_sg_entries;
3537 else if (indirect_sg_entries < cmd_sg_entries) {
3538 pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
3539 cmd_sg_entries);
3540 indirect_sg_entries = cmd_sg_entries;
3541 }
3542
3543 srp_remove_wq = create_workqueue("srp_remove");
3544 if (!srp_remove_wq) {
3545 ret = -ENOMEM;
3546 goto out;
3547 }
3548
3549 ret = -ENOMEM;
3550 ib_srp_transport_template =
3551 srp_attach_transport(&ib_srp_transport_functions);
3552 if (!ib_srp_transport_template)
3553 goto destroy_wq;
3554
3555 ret = class_register(&srp_class);
3556 if (ret) {
3557 pr_err("couldn't register class infiniband_srp\n");
3558 goto release_tr;
3559 }
3560
3561 ib_sa_register_client(&srp_sa_client);
3562
3563 ret = ib_register_client(&srp_client);
3564 if (ret) {
3565 pr_err("couldn't register IB client\n");
3566 goto unreg_sa;
3567 }
3568
3569 out:
3570 return ret;
3571
3572 unreg_sa:
3573 ib_sa_unregister_client(&srp_sa_client);
3574 class_unregister(&srp_class);
3575
3576 release_tr:
3577 srp_release_transport(ib_srp_transport_template);
3578
3579 destroy_wq:
3580 destroy_workqueue(srp_remove_wq);
3581 goto out;
3582 }
3583
3584 static void __exit srp_cleanup_module(void)
3585 {
3586 ib_unregister_client(&srp_client);
3587 ib_sa_unregister_client(&srp_sa_client);
3588 class_unregister(&srp_class);
3589 srp_release_transport(ib_srp_transport_template);
3590 destroy_workqueue(srp_remove_wq);
3591 }
3592
3593 module_init(srp_init_module);
3594 module_exit(srp_cleanup_module);
Linux with added FPC-III support