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Linux 4.1.16
[linux/fpc-iii.git] / drivers / infiniband / ulp / srp / ib_srp.c
blob025f931054447cafe5201259f680d90e0cd80598
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 "v" DRV_VERSION " (" DRV_RELDATE ")");
64 MODULE_LICENSE("Dual BSD/GPL");
65
66 static unsigned int srp_sg_tablesize;
67 static unsigned int cmd_sg_entries;
68 static unsigned int indirect_sg_entries;
69 static bool allow_ext_sg;
70 static bool prefer_fr;
71 static bool register_always;
72 static int topspin_workarounds = 1;
73
74 module_param(srp_sg_tablesize, uint, 0444);
75 MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
76
77 module_param(cmd_sg_entries, uint, 0444);
78 MODULE_PARM_DESC(cmd_sg_entries,
79 "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
80
81 module_param(indirect_sg_entries, uint, 0444);
82 MODULE_PARM_DESC(indirect_sg_entries,
83 "Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");
84
85 module_param(allow_ext_sg, bool, 0444);
86 MODULE_PARM_DESC(allow_ext_sg,
87 "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");
88
89 module_param(topspin_workarounds, int, 0444);
90 MODULE_PARM_DESC(topspin_workarounds,
91 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
92
93 module_param(prefer_fr, bool, 0444);
94 MODULE_PARM_DESC(prefer_fr,
95 "Whether to use fast registration if both FMR and fast registration are supported");
96
97 module_param(register_always, bool, 0444);
98 MODULE_PARM_DESC(register_always,
99 "Use memory registration even for contiguous memory regions");
100
101 static struct kernel_param_ops srp_tmo_ops;
102
103 static int srp_reconnect_delay = 10;
104 module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
105 S_IRUGO | S_IWUSR);
106 MODULE_PARM_DESC(reconnect_delay, "Time between successive reconnect attempts");
107
108 static int srp_fast_io_fail_tmo = 15;
109 module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
110 S_IRUGO | S_IWUSR);
111 MODULE_PARM_DESC(fast_io_fail_tmo,
112 "Number of seconds between the observation of a transport"
113 " layer error and failing all I/O. \"off\" means that this"
114 " functionality is disabled.");
115
116 static int srp_dev_loss_tmo = 600;
117 module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
118 S_IRUGO | S_IWUSR);
119 MODULE_PARM_DESC(dev_loss_tmo,
120 "Maximum number of seconds that the SRP transport should"
121 " insulate transport layer errors. After this time has been"
122 " exceeded the SCSI host is removed. Should be"
123 " between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
124 " if fast_io_fail_tmo has not been set. \"off\" means that"
125 " this functionality is disabled.");
126
127 static unsigned ch_count;
128 module_param(ch_count, uint, 0444);
129 MODULE_PARM_DESC(ch_count,
130 "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.");
131
132 static void srp_add_one(struct ib_device *device);
133 static void srp_remove_one(struct ib_device *device);
134 static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr);
135 static void srp_send_completion(struct ib_cq *cq, void *ch_ptr);
136 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
137
138 static struct scsi_transport_template *ib_srp_transport_template;
139 static struct workqueue_struct *srp_remove_wq;
140
141 static struct ib_client srp_client = {
142 .name = "srp",
143 .add = srp_add_one,
144 .remove = srp_remove_one
145 };
146
147 static struct ib_sa_client srp_sa_client;
148
149 static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
150 {
151 int tmo = *(int *)kp->arg;
152
153 if (tmo >= 0)
154 return sprintf(buffer, "%d", tmo);
155 else
156 return sprintf(buffer, "off");
157 }
158
159 static int srp_tmo_set(const char *val, const struct kernel_param *kp)
160 {
161 int tmo, res;
162
163 if (strncmp(val, "off", 3) != 0) {
164 res = kstrtoint(val, 0, &tmo);
165 if (res)
166 goto out;
167 } else {
168 tmo = -1;
169 }
170 if (kp->arg == &srp_reconnect_delay)
171 res = srp_tmo_valid(tmo, srp_fast_io_fail_tmo,
172 srp_dev_loss_tmo);
173 else if (kp->arg == &srp_fast_io_fail_tmo)
174 res = srp_tmo_valid(srp_reconnect_delay, tmo, srp_dev_loss_tmo);
175 else
176 res = srp_tmo_valid(srp_reconnect_delay, srp_fast_io_fail_tmo,
177 tmo);
178 if (res)
179 goto out;
180 *(int *)kp->arg = tmo;
181
182 out:
183 return res;
184 }
185
186 static struct kernel_param_ops srp_tmo_ops = {
187 .get = srp_tmo_get,
188 .set = srp_tmo_set,
189 };
190
191 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
192 {
193 return (struct srp_target_port *) host->hostdata;
194 }
195
196 static const char *srp_target_info(struct Scsi_Host *host)
197 {
198 return host_to_target(host)->target_name;
199 }
200
201 static int srp_target_is_topspin(struct srp_target_port *target)
202 {
203 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
204 static const u8 cisco_oui[3] = { 0x00, 0x1b, 0x0d };
205
206 return topspin_workarounds &&
207 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
208 !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
209 }
210
211 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
212 gfp_t gfp_mask,
213 enum dma_data_direction direction)
214 {
215 struct srp_iu *iu;
216
217 iu = kmalloc(sizeof *iu, gfp_mask);
218 if (!iu)
219 goto out;
220
221 iu->buf = kzalloc(size, gfp_mask);
222 if (!iu->buf)
223 goto out_free_iu;
224
225 iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
226 direction);
227 if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
228 goto out_free_buf;
229
230 iu->size = size;
231 iu->direction = direction;
232
233 return iu;
234
235 out_free_buf:
236 kfree(iu->buf);
237 out_free_iu:
238 kfree(iu);
239 out:
240 return NULL;
241 }
242
243 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
244 {
245 if (!iu)
246 return;
247
248 ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
249 iu->direction);
250 kfree(iu->buf);
251 kfree(iu);
252 }
253
254 static void srp_qp_event(struct ib_event *event, void *context)
255 {
256 pr_debug("QP event %d\n", event->event);
257 }
258
259 static int srp_init_qp(struct srp_target_port *target,
260 struct ib_qp *qp)
261 {
262 struct ib_qp_attr *attr;
263 int ret;
264
265 attr = kmalloc(sizeof *attr, GFP_KERNEL);
266 if (!attr)
267 return -ENOMEM;
268
269 ret = ib_find_cached_pkey(target->srp_host->srp_dev->dev,
270 target->srp_host->port,
271 be16_to_cpu(target->pkey),
272 &attr->pkey_index);
273 if (ret)
274 goto out;
275
276 attr->qp_state = IB_QPS_INIT;
277 attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
278 IB_ACCESS_REMOTE_WRITE);
279 attr->port_num = target->srp_host->port;
280
281 ret = ib_modify_qp(qp, attr,
282 IB_QP_STATE |
283 IB_QP_PKEY_INDEX |
284 IB_QP_ACCESS_FLAGS |
285 IB_QP_PORT);
286
287 out:
288 kfree(attr);
289 return ret;
290 }
291
292 static int srp_new_cm_id(struct srp_rdma_ch *ch)
293 {
294 struct srp_target_port *target = ch->target;
295 struct ib_cm_id *new_cm_id;
296
297 new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
298 srp_cm_handler, ch);
299 if (IS_ERR(new_cm_id))
300 return PTR_ERR(new_cm_id);
301
302 if (ch->cm_id)
303 ib_destroy_cm_id(ch->cm_id);
304 ch->cm_id = new_cm_id;
305 ch->path.sgid = target->sgid;
306 ch->path.dgid = target->orig_dgid;
307 ch->path.pkey = target->pkey;
308 ch->path.service_id = target->service_id;
309
310 return 0;
311 }
312
313 static struct ib_fmr_pool *srp_alloc_fmr_pool(struct srp_target_port *target)
314 {
315 struct srp_device *dev = target->srp_host->srp_dev;
316 struct ib_fmr_pool_param fmr_param;
317
318 memset(&fmr_param, 0, sizeof(fmr_param));
319 fmr_param.pool_size = target->scsi_host->can_queue;
320 fmr_param.dirty_watermark = fmr_param.pool_size / 4;
321 fmr_param.cache = 1;
322 fmr_param.max_pages_per_fmr = dev->max_pages_per_mr;
323 fmr_param.page_shift = ilog2(dev->mr_page_size);
324 fmr_param.access = (IB_ACCESS_LOCAL_WRITE |
325 IB_ACCESS_REMOTE_WRITE |
326 IB_ACCESS_REMOTE_READ);
327
328 return ib_create_fmr_pool(dev->pd, &fmr_param);
329 }
330
331 /**
332 * srp_destroy_fr_pool() - free the resources owned by a pool
333 * @pool: Fast registration pool to be destroyed.
334 */
335 static void srp_destroy_fr_pool(struct srp_fr_pool *pool)
336 {
337 int i;
338 struct srp_fr_desc *d;
339
340 if (!pool)
341 return;
342
343 for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
344 if (d->frpl)
345 ib_free_fast_reg_page_list(d->frpl);
346 if (d->mr)
347 ib_dereg_mr(d->mr);
348 }
349 kfree(pool);
350 }
351
352 /**
353 * srp_create_fr_pool() - allocate and initialize a pool for fast registration
354 * @device: IB device to allocate fast registration descriptors for.
355 * @pd: Protection domain associated with the FR descriptors.
356 * @pool_size: Number of descriptors to allocate.
357 * @max_page_list_len: Maximum fast registration work request page list length.
358 */
359 static struct srp_fr_pool *srp_create_fr_pool(struct ib_device *device,
360 struct ib_pd *pd, int pool_size,
361 int max_page_list_len)
362 {
363 struct srp_fr_pool *pool;
364 struct srp_fr_desc *d;
365 struct ib_mr *mr;
366 struct ib_fast_reg_page_list *frpl;
367 int i, ret = -EINVAL;
368
369 if (pool_size <= 0)
370 goto err;
371 ret = -ENOMEM;
372 pool = kzalloc(sizeof(struct srp_fr_pool) +
373 pool_size * sizeof(struct srp_fr_desc), GFP_KERNEL);
374 if (!pool)
375 goto err;
376 pool->size = pool_size;
377 pool->max_page_list_len = max_page_list_len;
378 spin_lock_init(&pool->lock);
379 INIT_LIST_HEAD(&pool->free_list);
380
381 for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) {
382 mr = ib_alloc_fast_reg_mr(pd, max_page_list_len);
383 if (IS_ERR(mr)) {
384 ret = PTR_ERR(mr);
385 goto destroy_pool;
386 }
387 d->mr = mr;
388 frpl = ib_alloc_fast_reg_page_list(device, max_page_list_len);
389 if (IS_ERR(frpl)) {
390 ret = PTR_ERR(frpl);
391 goto destroy_pool;
392 }
393 d->frpl = frpl;
394 list_add_tail(&d->entry, &pool->free_list);
395 }
396
397 out:
398 return pool;
399
400 destroy_pool:
401 srp_destroy_fr_pool(pool);
402
403 err:
404 pool = ERR_PTR(ret);
405 goto out;
406 }
407
408 /**
409 * srp_fr_pool_get() - obtain a descriptor suitable for fast registration
410 * @pool: Pool to obtain descriptor from.
411 */
412 static struct srp_fr_desc *srp_fr_pool_get(struct srp_fr_pool *pool)
413 {
414 struct srp_fr_desc *d = NULL;
415 unsigned long flags;
416
417 spin_lock_irqsave(&pool->lock, flags);
418 if (!list_empty(&pool->free_list)) {
419 d = list_first_entry(&pool->free_list, typeof(*d), entry);
420 list_del(&d->entry);
421 }
422 spin_unlock_irqrestore(&pool->lock, flags);
423
424 return d;
425 }
426
427 /**
428 * srp_fr_pool_put() - put an FR descriptor back in the free list
429 * @pool: Pool the descriptor was allocated from.
430 * @desc: Pointer to an array of fast registration descriptor pointers.
431 * @n: Number of descriptors to put back.
432 *
433 * Note: The caller must already have queued an invalidation request for
434 * desc->mr->rkey before calling this function.
435 */
436 static void srp_fr_pool_put(struct srp_fr_pool *pool, struct srp_fr_desc **desc,
437 int n)
438 {
439 unsigned long flags;
440 int i;
441
442 spin_lock_irqsave(&pool->lock, flags);
443 for (i = 0; i < n; i++)
444 list_add(&desc[i]->entry, &pool->free_list);
445 spin_unlock_irqrestore(&pool->lock, flags);
446 }
447
448 static struct srp_fr_pool *srp_alloc_fr_pool(struct srp_target_port *target)
449 {
450 struct srp_device *dev = target->srp_host->srp_dev;
451
452 return srp_create_fr_pool(dev->dev, dev->pd,
453 target->scsi_host->can_queue,
454 dev->max_pages_per_mr);
455 }
456
457 /**
458 * srp_destroy_qp() - destroy an RDMA queue pair
459 * @ch: SRP RDMA channel.
460 *
461 * Change a queue pair into the error state and wait until all receive
462 * completions have been processed before destroying it. This avoids that
463 * the receive completion handler can access the queue pair while it is
464 * being destroyed.
465 */
466 static void srp_destroy_qp(struct srp_rdma_ch *ch)
467 {
468 static struct ib_qp_attr attr = { .qp_state = IB_QPS_ERR };
469 static struct ib_recv_wr wr = { .wr_id = SRP_LAST_WR_ID };
470 struct ib_recv_wr *bad_wr;
471 int ret;
472
473 /* Destroying a QP and reusing ch->done is only safe if not connected */
474 WARN_ON_ONCE(ch->connected);
475
476 ret = ib_modify_qp(ch->qp, &attr, IB_QP_STATE);
477 WARN_ONCE(ret, "ib_cm_init_qp_attr() returned %d\n", ret);
478 if (ret)
479 goto out;
480
481 init_completion(&ch->done);
482 ret = ib_post_recv(ch->qp, &wr, &bad_wr);
483 WARN_ONCE(ret, "ib_post_recv() returned %d\n", ret);
484 if (ret == 0)
485 wait_for_completion(&ch->done);
486
487 out:
488 ib_destroy_qp(ch->qp);
489 }
490
491 static int srp_create_ch_ib(struct srp_rdma_ch *ch)
492 {
493 struct srp_target_port *target = ch->target;
494 struct srp_device *dev = target->srp_host->srp_dev;
495 struct ib_qp_init_attr *init_attr;
496 struct ib_cq *recv_cq, *send_cq;
497 struct ib_qp *qp;
498 struct ib_fmr_pool *fmr_pool = NULL;
499 struct srp_fr_pool *fr_pool = NULL;
500 const int m = 1 + dev->use_fast_reg;
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 recv_cq = ib_create_cq(dev->dev, srp_recv_completion, NULL, ch,
509 target->queue_size + 1, ch->comp_vector);
510 if (IS_ERR(recv_cq)) {
511 ret = PTR_ERR(recv_cq);
512 goto err;
513 }
514
515 send_cq = ib_create_cq(dev->dev, srp_send_completion, NULL, ch,
516 m * target->queue_size, ch->comp_vector);
517 if (IS_ERR(send_cq)) {
518 ret = PTR_ERR(send_cq);
519 goto err_recv_cq;
520 }
521
522 ib_req_notify_cq(recv_cq, IB_CQ_NEXT_COMP);
523
524 init_attr->event_handler = srp_qp_event;
525 init_attr->cap.max_send_wr = m * target->queue_size;
526 init_attr->cap.max_recv_wr = target->queue_size + 1;
527 init_attr->cap.max_recv_sge = 1;
528 init_attr->cap.max_send_sge = 1;
529 init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
530 init_attr->qp_type = IB_QPT_RC;
531 init_attr->send_cq = send_cq;
532 init_attr->recv_cq = recv_cq;
533
534 qp = ib_create_qp(dev->pd, init_attr);
535 if (IS_ERR(qp)) {
536 ret = PTR_ERR(qp);
537 goto err_send_cq;
538 }
539
540 ret = srp_init_qp(target, qp);
541 if (ret)
542 goto err_qp;
543
544 if (dev->use_fast_reg && dev->has_fr) {
545 fr_pool = srp_alloc_fr_pool(target);
546 if (IS_ERR(fr_pool)) {
547 ret = PTR_ERR(fr_pool);
548 shost_printk(KERN_WARNING, target->scsi_host, PFX
549 "FR pool allocation failed (%d)\n", ret);
550 goto err_qp;
551 }
552 if (ch->fr_pool)
553 srp_destroy_fr_pool(ch->fr_pool);
554 ch->fr_pool = fr_pool;
555 } else if (!dev->use_fast_reg && dev->has_fmr) {
556 fmr_pool = srp_alloc_fmr_pool(target);
557 if (IS_ERR(fmr_pool)) {
558 ret = PTR_ERR(fmr_pool);
559 shost_printk(KERN_WARNING, target->scsi_host, PFX
560 "FMR pool allocation failed (%d)\n", ret);
561 goto err_qp;
562 }
563 if (ch->fmr_pool)
564 ib_destroy_fmr_pool(ch->fmr_pool);
565 ch->fmr_pool = fmr_pool;
566 }
567
568 if (ch->qp)
569 srp_destroy_qp(ch);
570 if (ch->recv_cq)
571 ib_destroy_cq(ch->recv_cq);
572 if (ch->send_cq)
573 ib_destroy_cq(ch->send_cq);
574
575 ch->qp = qp;
576 ch->recv_cq = recv_cq;
577 ch->send_cq = send_cq;
578
579 kfree(init_attr);
580 return 0;
581
582 err_qp:
583 ib_destroy_qp(qp);
584
585 err_send_cq:
586 ib_destroy_cq(send_cq);
587
588 err_recv_cq:
589 ib_destroy_cq(recv_cq);
590
591 err:
592 kfree(init_attr);
593 return ret;
594 }
595
596 /*
597 * Note: this function may be called without srp_alloc_iu_bufs() having been
598 * invoked. Hence the ch->[rt]x_ring checks.
599 */
600 static void srp_free_ch_ib(struct srp_target_port *target,
601 struct srp_rdma_ch *ch)
602 {
603 struct srp_device *dev = target->srp_host->srp_dev;
604 int i;
605
606 if (!ch->target)
607 return;
608
609 if (ch->cm_id) {
610 ib_destroy_cm_id(ch->cm_id);
611 ch->cm_id = NULL;
612 }
613
614 /* If srp_new_cm_id() succeeded but srp_create_ch_ib() not, return. */
615 if (!ch->qp)
616 return;
617
618 if (dev->use_fast_reg) {
619 if (ch->fr_pool)
620 srp_destroy_fr_pool(ch->fr_pool);
621 } else {
622 if (ch->fmr_pool)
623 ib_destroy_fmr_pool(ch->fmr_pool);
624 }
625 srp_destroy_qp(ch);
626 ib_destroy_cq(ch->send_cq);
627 ib_destroy_cq(ch->recv_cq);
628
629 /*
630 * Avoid that the SCSI error handler tries to use this channel after
631 * it has been freed. The SCSI error handler can namely continue
632 * trying to perform recovery actions after scsi_remove_host()
633 * returned.
634 */
635 ch->target = NULL;
636
637 ch->qp = NULL;
638 ch->send_cq = ch->recv_cq = NULL;
639
640 if (ch->rx_ring) {
641 for (i = 0; i < target->queue_size; ++i)
642 srp_free_iu(target->srp_host, ch->rx_ring[i]);
643 kfree(ch->rx_ring);
644 ch->rx_ring = NULL;
645 }
646 if (ch->tx_ring) {
647 for (i = 0; i < target->queue_size; ++i)
648 srp_free_iu(target->srp_host, ch->tx_ring[i]);
649 kfree(ch->tx_ring);
650 ch->tx_ring = NULL;
651 }
652 }
653
654 static void srp_path_rec_completion(int status,
655 struct ib_sa_path_rec *pathrec,
656 void *ch_ptr)
657 {
658 struct srp_rdma_ch *ch = ch_ptr;
659 struct srp_target_port *target = ch->target;
660
661 ch->status = status;
662 if (status)
663 shost_printk(KERN_ERR, target->scsi_host,
664 PFX "Got failed path rec status %d\n", status);
665 else
666 ch->path = *pathrec;
667 complete(&ch->done);
668 }
669
670 static int srp_lookup_path(struct srp_rdma_ch *ch)
671 {
672 struct srp_target_port *target = ch->target;
673 int ret;
674
675 ch->path.numb_path = 1;
676
677 init_completion(&ch->done);
678
679 ch->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
680 target->srp_host->srp_dev->dev,
681 target->srp_host->port,
682 &ch->path,
683 IB_SA_PATH_REC_SERVICE_ID |
684 IB_SA_PATH_REC_DGID |
685 IB_SA_PATH_REC_SGID |
686 IB_SA_PATH_REC_NUMB_PATH |
687 IB_SA_PATH_REC_PKEY,
688 SRP_PATH_REC_TIMEOUT_MS,
689 GFP_KERNEL,
690 srp_path_rec_completion,
691 ch, &ch->path_query);
692 if (ch->path_query_id < 0)
693 return ch->path_query_id;
694
695 ret = wait_for_completion_interruptible(&ch->done);
696 if (ret < 0)
697 return ret;
698
699 if (ch->status < 0)
700 shost_printk(KERN_WARNING, target->scsi_host,
701 PFX "Path record query failed\n");
702
703 return ch->status;
704 }
705
706 static int srp_send_req(struct srp_rdma_ch *ch, bool multich)
707 {
708 struct srp_target_port *target = ch->target;
709 struct {
710 struct ib_cm_req_param param;
711 struct srp_login_req priv;
712 } *req = NULL;
713 int status;
714
715 req = kzalloc(sizeof *req, GFP_KERNEL);
716 if (!req)
717 return -ENOMEM;
718
719 req->param.primary_path = &ch->path;
720 req->param.alternate_path = NULL;
721 req->param.service_id = target->service_id;
722 req->param.qp_num = ch->qp->qp_num;
723 req->param.qp_type = ch->qp->qp_type;
724 req->param.private_data = &req->priv;
725 req->param.private_data_len = sizeof req->priv;
726 req->param.flow_control = 1;
727
728 get_random_bytes(&req->param.starting_psn, 4);
729 req->param.starting_psn &= 0xffffff;
730
731 /*
732 * Pick some arbitrary defaults here; we could make these
733 * module parameters if anyone cared about setting them.
734 */
735 req->param.responder_resources = 4;
736 req->param.remote_cm_response_timeout = 20;
737 req->param.local_cm_response_timeout = 20;
738 req->param.retry_count = target->tl_retry_count;
739 req->param.rnr_retry_count = 7;
740 req->param.max_cm_retries = 15;
741
742 req->priv.opcode = SRP_LOGIN_REQ;
743 req->priv.tag = 0;
744 req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
745 req->priv.req_buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
746 SRP_BUF_FORMAT_INDIRECT);
747 req->priv.req_flags = (multich ? SRP_MULTICHAN_MULTI :
748 SRP_MULTICHAN_SINGLE);
749 /*
750 * In the published SRP specification (draft rev. 16a), the
751 * port identifier format is 8 bytes of ID extension followed
752 * by 8 bytes of GUID. Older drafts put the two halves in the
753 * opposite order, so that the GUID comes first.
754 *
755 * Targets conforming to these obsolete drafts can be
756 * recognized by the I/O Class they report.
757 */
758 if (target->io_class == SRP_REV10_IB_IO_CLASS) {
759 memcpy(req->priv.initiator_port_id,
760 &target->sgid.global.interface_id, 8);
761 memcpy(req->priv.initiator_port_id + 8,
762 &target->initiator_ext, 8);
763 memcpy(req->priv.target_port_id, &target->ioc_guid, 8);
764 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
765 } else {
766 memcpy(req->priv.initiator_port_id,
767 &target->initiator_ext, 8);
768 memcpy(req->priv.initiator_port_id + 8,
769 &target->sgid.global.interface_id, 8);
770 memcpy(req->priv.target_port_id, &target->id_ext, 8);
771 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
772 }
773
774 /*
775 * Topspin/Cisco SRP targets will reject our login unless we
776 * zero out the first 8 bytes of our initiator port ID and set
777 * the second 8 bytes to the local node GUID.
778 */
779 if (srp_target_is_topspin(target)) {
780 shost_printk(KERN_DEBUG, target->scsi_host,
781 PFX "Topspin/Cisco initiator port ID workaround "
782 "activated for target GUID %016llx\n",
783 (unsigned long long) be64_to_cpu(target->ioc_guid));
784 memset(req->priv.initiator_port_id, 0, 8);
785 memcpy(req->priv.initiator_port_id + 8,
786 &target->srp_host->srp_dev->dev->node_guid, 8);
787 }
788
789 status = ib_send_cm_req(ch->cm_id, &req->param);
790
791 kfree(req);
792
793 return status;
794 }
795
796 static bool srp_queue_remove_work(struct srp_target_port *target)
797 {
798 bool changed = false;
799
800 spin_lock_irq(&target->lock);
801 if (target->state != SRP_TARGET_REMOVED) {
802 target->state = SRP_TARGET_REMOVED;
803 changed = true;
804 }
805 spin_unlock_irq(&target->lock);
806
807 if (changed)
808 queue_work(srp_remove_wq, &target->remove_work);
809
810 return changed;
811 }
812
813 static void srp_disconnect_target(struct srp_target_port *target)
814 {
815 struct srp_rdma_ch *ch;
816 int i;
817
818 /* XXX should send SRP_I_LOGOUT request */
819
820 for (i = 0; i < target->ch_count; i++) {
821 ch = &target->ch[i];
822 ch->connected = false;
823 if (ch->cm_id && ib_send_cm_dreq(ch->cm_id, NULL, 0)) {
824 shost_printk(KERN_DEBUG, target->scsi_host,
825 PFX "Sending CM DREQ failed\n");
826 }
827 }
828 }
829
830 static void srp_free_req_data(struct srp_target_port *target,
831 struct srp_rdma_ch *ch)
832 {
833 struct srp_device *dev = target->srp_host->srp_dev;
834 struct ib_device *ibdev = dev->dev;
835 struct srp_request *req;
836 int i;
837
838 if (!ch->target || !ch->req_ring)
839 return;
840
841 for (i = 0; i < target->req_ring_size; ++i) {
842 req = &ch->req_ring[i];
843 if (dev->use_fast_reg)
844 kfree(req->fr_list);
845 else
846 kfree(req->fmr_list);
847 kfree(req->map_page);
848 if (req->indirect_dma_addr) {
849 ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
850 target->indirect_size,
851 DMA_TO_DEVICE);
852 }
853 kfree(req->indirect_desc);
854 }
855
856 kfree(ch->req_ring);
857 ch->req_ring = NULL;
858 }
859
860 static int srp_alloc_req_data(struct srp_rdma_ch *ch)
861 {
862 struct srp_target_port *target = ch->target;
863 struct srp_device *srp_dev = target->srp_host->srp_dev;
864 struct ib_device *ibdev = srp_dev->dev;
865 struct srp_request *req;
866 void *mr_list;
867 dma_addr_t dma_addr;
868 int i, ret = -ENOMEM;
869
870 ch->req_ring = kcalloc(target->req_ring_size, sizeof(*ch->req_ring),
871 GFP_KERNEL);
872 if (!ch->req_ring)
873 goto out;
874
875 for (i = 0; i < target->req_ring_size; ++i) {
876 req = &ch->req_ring[i];
877 mr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
878 GFP_KERNEL);
879 if (!mr_list)
880 goto out;
881 if (srp_dev->use_fast_reg)
882 req->fr_list = mr_list;
883 else
884 req->fmr_list = mr_list;
885 req->map_page = kmalloc(srp_dev->max_pages_per_mr *
886 sizeof(void *), GFP_KERNEL);
887 if (!req->map_page)
888 goto out;
889 req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
890 if (!req->indirect_desc)
891 goto out;
892
893 dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
894 target->indirect_size,
895 DMA_TO_DEVICE);
896 if (ib_dma_mapping_error(ibdev, dma_addr))
897 goto out;
898
899 req->indirect_dma_addr = dma_addr;
900 }
901 ret = 0;
902
903 out:
904 return ret;
905 }
906
907 /**
908 * srp_del_scsi_host_attr() - Remove attributes defined in the host template.
909 * @shost: SCSI host whose attributes to remove from sysfs.
910 *
911 * Note: Any attributes defined in the host template and that did not exist
912 * before invocation of this function will be ignored.
913 */
914 static void srp_del_scsi_host_attr(struct Scsi_Host *shost)
915 {
916 struct device_attribute **attr;
917
918 for (attr = shost->hostt->shost_attrs; attr && *attr; ++attr)
919 device_remove_file(&shost->shost_dev, *attr);
920 }
921
922 static void srp_remove_target(struct srp_target_port *target)
923 {
924 struct srp_rdma_ch *ch;
925 int i;
926
927 WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
928
929 srp_del_scsi_host_attr(target->scsi_host);
930 srp_rport_get(target->rport);
931 srp_remove_host(target->scsi_host);
932 scsi_remove_host(target->scsi_host);
933 srp_stop_rport_timers(target->rport);
934 srp_disconnect_target(target);
935 for (i = 0; i < target->ch_count; i++) {
936 ch = &target->ch[i];
937 srp_free_ch_ib(target, ch);
938 }
939 cancel_work_sync(&target->tl_err_work);
940 srp_rport_put(target->rport);
941 for (i = 0; i < target->ch_count; i++) {
942 ch = &target->ch[i];
943 srp_free_req_data(target, ch);
944 }
945 kfree(target->ch);
946 target->ch = NULL;
947
948 spin_lock(&target->srp_host->target_lock);
949 list_del(&target->list);
950 spin_unlock(&target->srp_host->target_lock);
951
952 scsi_host_put(target->scsi_host);
953 }
954
955 static void srp_remove_work(struct work_struct *work)
956 {
957 struct srp_target_port *target =
958 container_of(work, struct srp_target_port, remove_work);
959
960 WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
961
962 srp_remove_target(target);
963 }
964
965 static void srp_rport_delete(struct srp_rport *rport)
966 {
967 struct srp_target_port *target = rport->lld_data;
968
969 srp_queue_remove_work(target);
970 }
971
972 /**
973 * srp_connected_ch() - number of connected channels
974 * @target: SRP target port.
975 */
976 static int srp_connected_ch(struct srp_target_port *target)
977 {
978 int i, c = 0;
979
980 for (i = 0; i < target->ch_count; i++)
981 c += target->ch[i].connected;
982
983 return c;
984 }
985
986 static int srp_connect_ch(struct srp_rdma_ch *ch, bool multich)
987 {
988 struct srp_target_port *target = ch->target;
989 int ret;
990
991 WARN_ON_ONCE(!multich && srp_connected_ch(target) > 0);
992
993 ret = srp_lookup_path(ch);
994 if (ret)
995 return ret;
996
997 while (1) {
998 init_completion(&ch->done);
999 ret = srp_send_req(ch, multich);
1000 if (ret)
1001 return ret;
1002 ret = wait_for_completion_interruptible(&ch->done);
1003 if (ret < 0)
1004 return ret;
1005
1006 /*
1007 * The CM event handling code will set status to
1008 * SRP_PORT_REDIRECT if we get a port redirect REJ
1009 * back, or SRP_DLID_REDIRECT if we get a lid/qp
1010 * redirect REJ back.
1011 */
1012 switch (ch->status) {
1013 case 0:
1014 ch->connected = true;
1015 return 0;
1016
1017 case SRP_PORT_REDIRECT:
1018 ret = srp_lookup_path(ch);
1019 if (ret)
1020 return ret;
1021 break;
1022
1023 case SRP_DLID_REDIRECT:
1024 break;
1025
1026 case SRP_STALE_CONN:
1027 shost_printk(KERN_ERR, target->scsi_host, PFX
1028 "giving up on stale connection\n");
1029 ch->status = -ECONNRESET;
1030 return ch->status;
1031
1032 default:
1033 return ch->status;
1034 }
1035 }
1036 }
1037
1038 static int srp_inv_rkey(struct srp_rdma_ch *ch, u32 rkey)
1039 {
1040 struct ib_send_wr *bad_wr;
1041 struct ib_send_wr wr = {
1042 .opcode = IB_WR_LOCAL_INV,
1043 .wr_id = LOCAL_INV_WR_ID_MASK,
1044 .next = NULL,
1045 .num_sge = 0,
1046 .send_flags = 0,
1047 .ex.invalidate_rkey = rkey,
1048 };
1049
1050 return ib_post_send(ch->qp, &wr, &bad_wr);
1051 }
1052
1053 static void srp_unmap_data(struct scsi_cmnd *scmnd,
1054 struct srp_rdma_ch *ch,
1055 struct srp_request *req)
1056 {
1057 struct srp_target_port *target = ch->target;
1058 struct srp_device *dev = target->srp_host->srp_dev;
1059 struct ib_device *ibdev = dev->dev;
1060 int i, res;
1061
1062 if (!scsi_sglist(scmnd) ||
1063 (scmnd->sc_data_direction != DMA_TO_DEVICE &&
1064 scmnd->sc_data_direction != DMA_FROM_DEVICE))
1065 return;
1066
1067 if (dev->use_fast_reg) {
1068 struct srp_fr_desc **pfr;
1069
1070 for (i = req->nmdesc, pfr = req->fr_list; i > 0; i--, pfr++) {
1071 res = srp_inv_rkey(ch, (*pfr)->mr->rkey);
1072 if (res < 0) {
1073 shost_printk(KERN_ERR, target->scsi_host, PFX
1074 "Queueing INV WR for rkey %#x failed (%d)\n",
1075 (*pfr)->mr->rkey, res);
1076 queue_work(system_long_wq,
1077 &target->tl_err_work);
1078 }
1079 }
1080 if (req->nmdesc)
1081 srp_fr_pool_put(ch->fr_pool, req->fr_list,
1082 req->nmdesc);
1083 } else {
1084 struct ib_pool_fmr **pfmr;
1085
1086 for (i = req->nmdesc, pfmr = req->fmr_list; i > 0; i--, pfmr++)
1087 ib_fmr_pool_unmap(*pfmr);
1088 }
1089
1090 ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
1091 scmnd->sc_data_direction);
1092 }
1093
1094 /**
1095 * srp_claim_req - Take ownership of the scmnd associated with a request.
1096 * @ch: SRP RDMA channel.
1097 * @req: SRP request.
1098 * @sdev: If not NULL, only take ownership for this SCSI device.
1099 * @scmnd: If NULL, take ownership of @req->scmnd. If not NULL, only take
1100 * ownership of @req->scmnd if it equals @scmnd.
1101 *
1102 * Return value:
1103 * Either NULL or a pointer to the SCSI command the caller became owner of.
1104 */
1105 static struct scsi_cmnd *srp_claim_req(struct srp_rdma_ch *ch,
1106 struct srp_request *req,
1107 struct scsi_device *sdev,
1108 struct scsi_cmnd *scmnd)
1109 {
1110 unsigned long flags;
1111
1112 spin_lock_irqsave(&ch->lock, flags);
1113 if (req->scmnd &&
1114 (!sdev || req->scmnd->device == sdev) &&
1115 (!scmnd || req->scmnd == scmnd)) {
1116 scmnd = req->scmnd;
1117 req->scmnd = NULL;
1118 } else {
1119 scmnd = NULL;
1120 }
1121 spin_unlock_irqrestore(&ch->lock, flags);
1122
1123 return scmnd;
1124 }
1125
1126 /**
1127 * srp_free_req() - Unmap data and add request to the free request list.
1128 * @ch: SRP RDMA channel.
1129 * @req: Request to be freed.
1130 * @scmnd: SCSI command associated with @req.
1131 * @req_lim_delta: Amount to be added to @target->req_lim.
1132 */
1133 static void srp_free_req(struct srp_rdma_ch *ch, struct srp_request *req,
1134 struct scsi_cmnd *scmnd, s32 req_lim_delta)
1135 {
1136 unsigned long flags;
1137
1138 srp_unmap_data(scmnd, ch, req);
1139
1140 spin_lock_irqsave(&ch->lock, flags);
1141 ch->req_lim += req_lim_delta;
1142 spin_unlock_irqrestore(&ch->lock, flags);
1143 }
1144
1145 static void srp_finish_req(struct srp_rdma_ch *ch, struct srp_request *req,
1146 struct scsi_device *sdev, int result)
1147 {
1148 struct scsi_cmnd *scmnd = srp_claim_req(ch, req, sdev, NULL);
1149
1150 if (scmnd) {
1151 srp_free_req(ch, req, scmnd, 0);
1152 scmnd->result = result;
1153 scmnd->scsi_done(scmnd);
1154 }
1155 }
1156
1157 static void srp_terminate_io(struct srp_rport *rport)
1158 {
1159 struct srp_target_port *target = rport->lld_data;
1160 struct srp_rdma_ch *ch;
1161 struct Scsi_Host *shost = target->scsi_host;
1162 struct scsi_device *sdev;
1163 int i, j;
1164
1165 /*
1166 * Invoking srp_terminate_io() while srp_queuecommand() is running
1167 * is not safe. Hence the warning statement below.
1168 */
1169 shost_for_each_device(sdev, shost)
1170 WARN_ON_ONCE(sdev->request_queue->request_fn_active);
1171
1172 for (i = 0; i < target->ch_count; i++) {
1173 ch = &target->ch[i];
1174
1175 for (j = 0; j < target->req_ring_size; ++j) {
1176 struct srp_request *req = &ch->req_ring[j];
1177
1178 srp_finish_req(ch, req, NULL,
1179 DID_TRANSPORT_FAILFAST << 16);
1180 }
1181 }
1182 }
1183
1184 /*
1185 * It is up to the caller to ensure that srp_rport_reconnect() calls are
1186 * serialized and that no concurrent srp_queuecommand(), srp_abort(),
1187 * srp_reset_device() or srp_reset_host() calls will occur while this function
1188 * is in progress. One way to realize that is not to call this function
1189 * directly but to call srp_reconnect_rport() instead since that last function
1190 * serializes calls of this function via rport->mutex and also blocks
1191 * srp_queuecommand() calls before invoking this function.
1192 */
1193 static int srp_rport_reconnect(struct srp_rport *rport)
1194 {
1195 struct srp_target_port *target = rport->lld_data;
1196 struct srp_rdma_ch *ch;
1197 int i, j, ret = 0;
1198 bool multich = false;
1199
1200 srp_disconnect_target(target);
1201
1202 if (target->state == SRP_TARGET_SCANNING)
1203 return -ENODEV;
1204
1205 /*
1206 * Now get a new local CM ID so that we avoid confusing the target in
1207 * case things are really fouled up. Doing so also ensures that all CM
1208 * callbacks will have finished before a new QP is allocated.
1209 */
1210 for (i = 0; i < target->ch_count; i++) {
1211 ch = &target->ch[i];
1212 if (!ch->target)
1213 break;
1214 ret += srp_new_cm_id(ch);
1215 }
1216 for (i = 0; i < target->ch_count; i++) {
1217 ch = &target->ch[i];
1218 if (!ch->target)
1219 break;
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 if (!ch->target)
1229 break;
1230 /*
1231 * Whether or not creating a new CM ID succeeded, create a new
1232 * QP. This guarantees that all completion callback function
1233 * invocations have finished before request resetting starts.
1234 */
1235 ret += srp_create_ch_ib(ch);
1236
1237 INIT_LIST_HEAD(&ch->free_tx);
1238 for (j = 0; j < target->queue_size; ++j)
1239 list_add(&ch->tx_ring[j]->list, &ch->free_tx);
1240 }
1241
1242 target->qp_in_error = false;
1243
1244 for (i = 0; i < target->ch_count; i++) {
1245 ch = &target->ch[i];
1246 if (ret || !ch->target)
1247 break;
1248 ret = srp_connect_ch(ch, multich);
1249 multich = true;
1250 }
1251
1252 if (ret == 0)
1253 shost_printk(KERN_INFO, target->scsi_host,
1254 PFX "reconnect succeeded\n");
1255
1256 return ret;
1257 }
1258
1259 static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
1260 unsigned int dma_len, u32 rkey)
1261 {
1262 struct srp_direct_buf *desc = state->desc;
1263
1264 desc->va = cpu_to_be64(dma_addr);
1265 desc->key = cpu_to_be32(rkey);
1266 desc->len = cpu_to_be32(dma_len);
1267
1268 state->total_len += dma_len;
1269 state->desc++;
1270 state->ndesc++;
1271 }
1272
1273 static int srp_map_finish_fmr(struct srp_map_state *state,
1274 struct srp_rdma_ch *ch)
1275 {
1276 struct ib_pool_fmr *fmr;
1277 u64 io_addr = 0;
1278
1279 fmr = ib_fmr_pool_map_phys(ch->fmr_pool, state->pages,
1280 state->npages, io_addr);
1281 if (IS_ERR(fmr))
1282 return PTR_ERR(fmr);
1283
1284 *state->next_fmr++ = fmr;
1285 state->nmdesc++;
1286
1287 srp_map_desc(state, 0, state->dma_len, fmr->fmr->rkey);
1288
1289 return 0;
1290 }
1291
1292 static int srp_map_finish_fr(struct srp_map_state *state,
1293 struct srp_rdma_ch *ch)
1294 {
1295 struct srp_target_port *target = ch->target;
1296 struct srp_device *dev = target->srp_host->srp_dev;
1297 struct ib_send_wr *bad_wr;
1298 struct ib_send_wr wr;
1299 struct srp_fr_desc *desc;
1300 u32 rkey;
1301
1302 desc = srp_fr_pool_get(ch->fr_pool);
1303 if (!desc)
1304 return -ENOMEM;
1305
1306 rkey = ib_inc_rkey(desc->mr->rkey);
1307 ib_update_fast_reg_key(desc->mr, rkey);
1308
1309 memcpy(desc->frpl->page_list, state->pages,
1310 sizeof(state->pages[0]) * state->npages);
1311
1312 memset(&wr, 0, sizeof(wr));
1313 wr.opcode = IB_WR_FAST_REG_MR;
1314 wr.wr_id = FAST_REG_WR_ID_MASK;
1315 wr.wr.fast_reg.iova_start = state->base_dma_addr;
1316 wr.wr.fast_reg.page_list = desc->frpl;
1317 wr.wr.fast_reg.page_list_len = state->npages;
1318 wr.wr.fast_reg.page_shift = ilog2(dev->mr_page_size);
1319 wr.wr.fast_reg.length = state->dma_len;
1320 wr.wr.fast_reg.access_flags = (IB_ACCESS_LOCAL_WRITE |
1321 IB_ACCESS_REMOTE_READ |
1322 IB_ACCESS_REMOTE_WRITE);
1323 wr.wr.fast_reg.rkey = desc->mr->lkey;
1324
1325 *state->next_fr++ = desc;
1326 state->nmdesc++;
1327
1328 srp_map_desc(state, state->base_dma_addr, state->dma_len,
1329 desc->mr->rkey);
1330
1331 return ib_post_send(ch->qp, &wr, &bad_wr);
1332 }
1333
1334 static int srp_finish_mapping(struct srp_map_state *state,
1335 struct srp_rdma_ch *ch)
1336 {
1337 struct srp_target_port *target = ch->target;
1338 int ret = 0;
1339
1340 if (state->npages == 0)
1341 return 0;
1342
1343 if (state->npages == 1 && !register_always)
1344 srp_map_desc(state, state->base_dma_addr, state->dma_len,
1345 target->rkey);
1346 else
1347 ret = target->srp_host->srp_dev->use_fast_reg ?
1348 srp_map_finish_fr(state, ch) :
1349 srp_map_finish_fmr(state, ch);
1350
1351 if (ret == 0) {
1352 state->npages = 0;
1353 state->dma_len = 0;
1354 }
1355
1356 return ret;
1357 }
1358
1359 static void srp_map_update_start(struct srp_map_state *state,
1360 struct scatterlist *sg, int sg_index,
1361 dma_addr_t dma_addr)
1362 {
1363 state->unmapped_sg = sg;
1364 state->unmapped_index = sg_index;
1365 state->unmapped_addr = dma_addr;
1366 }
1367
1368 static int srp_map_sg_entry(struct srp_map_state *state,
1369 struct srp_rdma_ch *ch,
1370 struct scatterlist *sg, int sg_index,
1371 bool use_mr)
1372 {
1373 struct srp_target_port *target = ch->target;
1374 struct srp_device *dev = target->srp_host->srp_dev;
1375 struct ib_device *ibdev = dev->dev;
1376 dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
1377 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
1378 unsigned int len;
1379 int ret;
1380
1381 if (!dma_len)
1382 return 0;
1383
1384 if (!use_mr) {
1385 /*
1386 * Once we're in direct map mode for a request, we don't
1387 * go back to FMR or FR mode, so no need to update anything
1388 * other than the descriptor.
1389 */
1390 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1391 return 0;
1392 }
1393
1394 /*
1395 * Since not all RDMA HW drivers support non-zero page offsets for
1396 * FMR, if we start at an offset into a page, don't merge into the
1397 * current FMR mapping. Finish it out, and use the kernel's MR for
1398 * this sg entry.
1399 */
1400 if ((!dev->use_fast_reg && dma_addr & ~dev->mr_page_mask) ||
1401 dma_len > dev->mr_max_size) {
1402 ret = srp_finish_mapping(state, ch);
1403 if (ret)
1404 return ret;
1405
1406 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1407 srp_map_update_start(state, NULL, 0, 0);
1408 return 0;
1409 }
1410
1411 /*
1412 * If this is the first sg that will be mapped via FMR or via FR, save
1413 * our position. We need to know the first unmapped entry, its index,
1414 * and the first unmapped address within that entry to be able to
1415 * restart mapping after an error.
1416 */
1417 if (!state->unmapped_sg)
1418 srp_map_update_start(state, sg, sg_index, dma_addr);
1419
1420 while (dma_len) {
1421 unsigned offset = dma_addr & ~dev->mr_page_mask;
1422 if (state->npages == dev->max_pages_per_mr || offset != 0) {
1423 ret = srp_finish_mapping(state, ch);
1424 if (ret)
1425 return ret;
1426
1427 srp_map_update_start(state, sg, sg_index, dma_addr);
1428 }
1429
1430 len = min_t(unsigned int, dma_len, dev->mr_page_size - offset);
1431
1432 if (!state->npages)
1433 state->base_dma_addr = dma_addr;
1434 state->pages[state->npages++] = dma_addr & dev->mr_page_mask;
1435 state->dma_len += len;
1436 dma_addr += len;
1437 dma_len -= len;
1438 }
1439
1440 /*
1441 * If the last entry of the MR wasn't a full page, then we need to
1442 * close it out and start a new one -- we can only merge at page
1443 * boundries.
1444 */
1445 ret = 0;
1446 if (len != dev->mr_page_size) {
1447 ret = srp_finish_mapping(state, ch);
1448 if (!ret)
1449 srp_map_update_start(state, NULL, 0, 0);
1450 }
1451 return ret;
1452 }
1453
1454 static int srp_map_sg(struct srp_map_state *state, struct srp_rdma_ch *ch,
1455 struct srp_request *req, struct scatterlist *scat,
1456 int count)
1457 {
1458 struct srp_target_port *target = ch->target;
1459 struct srp_device *dev = target->srp_host->srp_dev;
1460 struct ib_device *ibdev = dev->dev;
1461 struct scatterlist *sg;
1462 int i;
1463 bool use_mr;
1464
1465 state->desc = req->indirect_desc;
1466 state->pages = req->map_page;
1467 if (dev->use_fast_reg) {
1468 state->next_fr = req->fr_list;
1469 use_mr = !!ch->fr_pool;
1470 } else {
1471 state->next_fmr = req->fmr_list;
1472 use_mr = !!ch->fmr_pool;
1473 }
1474
1475 for_each_sg(scat, sg, count, i) {
1476 if (srp_map_sg_entry(state, ch, sg, i, use_mr)) {
1477 /*
1478 * Memory registration failed, so backtrack to the
1479 * first unmapped entry and continue on without using
1480 * memory registration.
1481 */
1482 dma_addr_t dma_addr;
1483 unsigned int dma_len;
1484
1485 backtrack:
1486 sg = state->unmapped_sg;
1487 i = state->unmapped_index;
1488
1489 dma_addr = ib_sg_dma_address(ibdev, sg);
1490 dma_len = ib_sg_dma_len(ibdev, sg);
1491 dma_len -= (state->unmapped_addr - dma_addr);
1492 dma_addr = state->unmapped_addr;
1493 use_mr = false;
1494 srp_map_desc(state, dma_addr, dma_len, target->rkey);
1495 }
1496 }
1497
1498 if (use_mr && srp_finish_mapping(state, ch))
1499 goto backtrack;
1500
1501 req->nmdesc = state->nmdesc;
1502
1503 return 0;
1504 }
1505
1506 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_rdma_ch *ch,
1507 struct srp_request *req)
1508 {
1509 struct srp_target_port *target = ch->target;
1510 struct scatterlist *scat;
1511 struct srp_cmd *cmd = req->cmd->buf;
1512 int len, nents, count;
1513 struct srp_device *dev;
1514 struct ib_device *ibdev;
1515 struct srp_map_state state;
1516 struct srp_indirect_buf *indirect_hdr;
1517 u32 table_len;
1518 u8 fmt;
1519
1520 if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
1521 return sizeof (struct srp_cmd);
1522
1523 if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
1524 scmnd->sc_data_direction != DMA_TO_DEVICE) {
1525 shost_printk(KERN_WARNING, target->scsi_host,
1526 PFX "Unhandled data direction %d\n",
1527 scmnd->sc_data_direction);
1528 return -EINVAL;
1529 }
1530
1531 nents = scsi_sg_count(scmnd);
1532 scat = scsi_sglist(scmnd);
1533
1534 dev = target->srp_host->srp_dev;
1535 ibdev = dev->dev;
1536
1537 count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
1538 if (unlikely(count == 0))
1539 return -EIO;
1540
1541 fmt = SRP_DATA_DESC_DIRECT;
1542 len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
1543
1544 if (count == 1 && !register_always) {
1545 /*
1546 * The midlayer only generated a single gather/scatter
1547 * entry, or DMA mapping coalesced everything to a
1548 * single entry. So a direct descriptor along with
1549 * the DMA MR suffices.
1550 */
1551 struct srp_direct_buf *buf = (void *) cmd->add_data;
1552
1553 buf->va = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
1554 buf->key = cpu_to_be32(target->rkey);
1555 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
1556
1557 req->nmdesc = 0;
1558 goto map_complete;
1559 }
1560
1561 /*
1562 * We have more than one scatter/gather entry, so build our indirect
1563 * descriptor table, trying to merge as many entries as we can.
1564 */
1565 indirect_hdr = (void *) cmd->add_data;
1566
1567 ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
1568 target->indirect_size, DMA_TO_DEVICE);
1569
1570 memset(&state, 0, sizeof(state));
1571 srp_map_sg(&state, ch, req, scat, count);
1572
1573 /* We've mapped the request, now pull as much of the indirect
1574 * descriptor table as we can into the command buffer. If this
1575 * target is not using an external indirect table, we are
1576 * guaranteed to fit into the command, as the SCSI layer won't
1577 * give us more S/G entries than we allow.
1578 */
1579 if (state.ndesc == 1) {
1580 /*
1581 * Memory registration collapsed the sg-list into one entry,
1582 * so use a direct descriptor.
1583 */
1584 struct srp_direct_buf *buf = (void *) cmd->add_data;
1585
1586 *buf = req->indirect_desc[0];
1587 goto map_complete;
1588 }
1589
1590 if (unlikely(target->cmd_sg_cnt < state.ndesc &&
1591 !target->allow_ext_sg)) {
1592 shost_printk(KERN_ERR, target->scsi_host,
1593 "Could not fit S/G list into SRP_CMD\n");
1594 return -EIO;
1595 }
1596
1597 count = min(state.ndesc, target->cmd_sg_cnt);
1598 table_len = state.ndesc * sizeof (struct srp_direct_buf);
1599
1600 fmt = SRP_DATA_DESC_INDIRECT;
1601 len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
1602 len += count * sizeof (struct srp_direct_buf);
1603
1604 memcpy(indirect_hdr->desc_list, req->indirect_desc,
1605 count * sizeof (struct srp_direct_buf));
1606
1607 indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
1608 indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
1609 indirect_hdr->table_desc.len = cpu_to_be32(table_len);
1610 indirect_hdr->len = cpu_to_be32(state.total_len);
1611
1612 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
1613 cmd->data_out_desc_cnt = count;
1614 else
1615 cmd->data_in_desc_cnt = count;
1616
1617 ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
1618 DMA_TO_DEVICE);
1619
1620 map_complete:
1621 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
1622 cmd->buf_fmt = fmt << 4;
1623 else
1624 cmd->buf_fmt = fmt;
1625
1626 return len;
1627 }
1628
1629 /*
1630 * Return an IU and possible credit to the free pool
1631 */
1632 static void srp_put_tx_iu(struct srp_rdma_ch *ch, struct srp_iu *iu,
1633 enum srp_iu_type iu_type)
1634 {
1635 unsigned long flags;
1636
1637 spin_lock_irqsave(&ch->lock, flags);
1638 list_add(&iu->list, &ch->free_tx);
1639 if (iu_type != SRP_IU_RSP)
1640 ++ch->req_lim;
1641 spin_unlock_irqrestore(&ch->lock, flags);
1642 }
1643
1644 /*
1645 * Must be called with ch->lock held to protect req_lim and free_tx.
1646 * If IU is not sent, it must be returned using srp_put_tx_iu().
1647 *
1648 * Note:
1649 * An upper limit for the number of allocated information units for each
1650 * request type is:
1651 * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
1652 * more than Scsi_Host.can_queue requests.
1653 * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
1654 * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
1655 * one unanswered SRP request to an initiator.
1656 */
1657 static struct srp_iu *__srp_get_tx_iu(struct srp_rdma_ch *ch,
1658 enum srp_iu_type iu_type)
1659 {
1660 struct srp_target_port *target = ch->target;
1661 s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
1662 struct srp_iu *iu;
1663
1664 srp_send_completion(ch->send_cq, ch);
1665
1666 if (list_empty(&ch->free_tx))
1667 return NULL;
1668
1669 /* Initiator responses to target requests do not consume credits */
1670 if (iu_type != SRP_IU_RSP) {
1671 if (ch->req_lim <= rsv) {
1672 ++target->zero_req_lim;
1673 return NULL;
1674 }
1675
1676 --ch->req_lim;
1677 }
1678
1679 iu = list_first_entry(&ch->free_tx, struct srp_iu, list);
1680 list_del(&iu->list);
1681 return iu;
1682 }
1683
1684 static int srp_post_send(struct srp_rdma_ch *ch, struct srp_iu *iu, int len)
1685 {
1686 struct srp_target_port *target = ch->target;
1687 struct ib_sge list;
1688 struct ib_send_wr wr, *bad_wr;
1689
1690 list.addr = iu->dma;
1691 list.length = len;
1692 list.lkey = target->lkey;
1693
1694 wr.next = NULL;
1695 wr.wr_id = (uintptr_t) iu;
1696 wr.sg_list = &list;
1697 wr.num_sge = 1;
1698 wr.opcode = IB_WR_SEND;
1699 wr.send_flags = IB_SEND_SIGNALED;
1700
1701 return ib_post_send(ch->qp, &wr, &bad_wr);
1702 }
1703
1704 static int srp_post_recv(struct srp_rdma_ch *ch, struct srp_iu *iu)
1705 {
1706 struct srp_target_port *target = ch->target;
1707 struct ib_recv_wr wr, *bad_wr;
1708 struct ib_sge list;
1709
1710 list.addr = iu->dma;
1711 list.length = iu->size;
1712 list.lkey = target->lkey;
1713
1714 wr.next = NULL;
1715 wr.wr_id = (uintptr_t) iu;
1716 wr.sg_list = &list;
1717 wr.num_sge = 1;
1718
1719 return ib_post_recv(ch->qp, &wr, &bad_wr);
1720 }
1721
1722 static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
1723 {
1724 struct srp_target_port *target = ch->target;
1725 struct srp_request *req;
1726 struct scsi_cmnd *scmnd;
1727 unsigned long flags;
1728
1729 if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1730 spin_lock_irqsave(&ch->lock, flags);
1731 ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
1732 spin_unlock_irqrestore(&ch->lock, flags);
1733
1734 ch->tsk_mgmt_status = -1;
1735 if (be32_to_cpu(rsp->resp_data_len) >= 4)
1736 ch->tsk_mgmt_status = rsp->data[3];
1737 complete(&ch->tsk_mgmt_done);
1738 } else {
1739 scmnd = scsi_host_find_tag(target->scsi_host, rsp->tag);
1740 if (scmnd) {
1741 req = (void *)scmnd->host_scribble;
1742 scmnd = srp_claim_req(ch, req, NULL, scmnd);
1743 }
1744 if (!scmnd) {
1745 shost_printk(KERN_ERR, target->scsi_host,
1746 "Null scmnd for RSP w/tag %#016llx received on ch %td / QP %#x\n",
1747 rsp->tag, ch - target->ch, ch->qp->qp_num);
1748
1749 spin_lock_irqsave(&ch->lock, flags);
1750 ch->req_lim += be32_to_cpu(rsp->req_lim_delta);
1751 spin_unlock_irqrestore(&ch->lock, flags);
1752
1753 return;
1754 }
1755 scmnd->result = rsp->status;
1756
1757 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
1758 memcpy(scmnd->sense_buffer, rsp->data +
1759 be32_to_cpu(rsp->resp_data_len),
1760 min_t(int, be32_to_cpu(rsp->sense_data_len),
1761 SCSI_SENSE_BUFFERSIZE));
1762 }
1763
1764 if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
1765 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
1766 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DIOVER))
1767 scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_in_res_cnt));
1768 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOUNDER))
1769 scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
1770 else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOOVER))
1771 scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_out_res_cnt));
1772
1773 srp_free_req(ch, req, scmnd,
1774 be32_to_cpu(rsp->req_lim_delta));
1775
1776 scmnd->host_scribble = NULL;
1777 scmnd->scsi_done(scmnd);
1778 }
1779 }
1780
1781 static int srp_response_common(struct srp_rdma_ch *ch, s32 req_delta,
1782 void *rsp, int len)
1783 {
1784 struct srp_target_port *target = ch->target;
1785 struct ib_device *dev = target->srp_host->srp_dev->dev;
1786 unsigned long flags;
1787 struct srp_iu *iu;
1788 int err;
1789
1790 spin_lock_irqsave(&ch->lock, flags);
1791 ch->req_lim += req_delta;
1792 iu = __srp_get_tx_iu(ch, SRP_IU_RSP);
1793 spin_unlock_irqrestore(&ch->lock, flags);
1794
1795 if (!iu) {
1796 shost_printk(KERN_ERR, target->scsi_host, PFX
1797 "no IU available to send response\n");
1798 return 1;
1799 }
1800
1801 ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
1802 memcpy(iu->buf, rsp, len);
1803 ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
1804
1805 err = srp_post_send(ch, iu, len);
1806 if (err) {
1807 shost_printk(KERN_ERR, target->scsi_host, PFX
1808 "unable to post response: %d\n", err);
1809 srp_put_tx_iu(ch, iu, SRP_IU_RSP);
1810 }
1811
1812 return err;
1813 }
1814
1815 static void srp_process_cred_req(struct srp_rdma_ch *ch,
1816 struct srp_cred_req *req)
1817 {
1818 struct srp_cred_rsp rsp = {
1819 .opcode = SRP_CRED_RSP,
1820 .tag = req->tag,
1821 };
1822 s32 delta = be32_to_cpu(req->req_lim_delta);
1823
1824 if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
1825 shost_printk(KERN_ERR, ch->target->scsi_host, PFX
1826 "problems processing SRP_CRED_REQ\n");
1827 }
1828
1829 static void srp_process_aer_req(struct srp_rdma_ch *ch,
1830 struct srp_aer_req *req)
1831 {
1832 struct srp_target_port *target = ch->target;
1833 struct srp_aer_rsp rsp = {
1834 .opcode = SRP_AER_RSP,
1835 .tag = req->tag,
1836 };
1837 s32 delta = be32_to_cpu(req->req_lim_delta);
1838
1839 shost_printk(KERN_ERR, target->scsi_host, PFX
1840 "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
1841
1842 if (srp_response_common(ch, delta, &rsp, sizeof(rsp)))
1843 shost_printk(KERN_ERR, target->scsi_host, PFX
1844 "problems processing SRP_AER_REQ\n");
1845 }
1846
1847 static void srp_handle_recv(struct srp_rdma_ch *ch, struct ib_wc *wc)
1848 {
1849 struct srp_target_port *target = ch->target;
1850 struct ib_device *dev = target->srp_host->srp_dev->dev;
1851 struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
1852 int res;
1853 u8 opcode;
1854
1855 ib_dma_sync_single_for_cpu(dev, iu->dma, ch->max_ti_iu_len,
1856 DMA_FROM_DEVICE);
1857
1858 opcode = *(u8 *) iu->buf;
1859
1860 if (0) {
1861 shost_printk(KERN_ERR, target->scsi_host,
1862 PFX "recv completion, opcode 0x%02x\n", opcode);
1863 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1864 iu->buf, wc->byte_len, true);
1865 }
1866
1867 switch (opcode) {
1868 case SRP_RSP:
1869 srp_process_rsp(ch, iu->buf);
1870 break;
1871
1872 case SRP_CRED_REQ:
1873 srp_process_cred_req(ch, iu->buf);
1874 break;
1875
1876 case SRP_AER_REQ:
1877 srp_process_aer_req(ch, iu->buf);
1878 break;
1879
1880 case SRP_T_LOGOUT:
1881 /* XXX Handle target logout */
1882 shost_printk(KERN_WARNING, target->scsi_host,
1883 PFX "Got target logout request\n");
1884 break;
1885
1886 default:
1887 shost_printk(KERN_WARNING, target->scsi_host,
1888 PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1889 break;
1890 }
1891
1892 ib_dma_sync_single_for_device(dev, iu->dma, ch->max_ti_iu_len,
1893 DMA_FROM_DEVICE);
1894
1895 res = srp_post_recv(ch, iu);
1896 if (res != 0)
1897 shost_printk(KERN_ERR, target->scsi_host,
1898 PFX "Recv failed with error code %d\n", res);
1899 }
1900
1901 /**
1902 * srp_tl_err_work() - handle a transport layer error
1903 * @work: Work structure embedded in an SRP target port.
1904 *
1905 * Note: This function may get invoked before the rport has been created,
1906 * hence the target->rport test.
1907 */
1908 static void srp_tl_err_work(struct work_struct *work)
1909 {
1910 struct srp_target_port *target;
1911
1912 target = container_of(work, struct srp_target_port, tl_err_work);
1913 if (target->rport)
1914 srp_start_tl_fail_timers(target->rport);
1915 }
1916
1917 static void srp_handle_qp_err(u64 wr_id, enum ib_wc_status wc_status,
1918 bool send_err, struct srp_rdma_ch *ch)
1919 {
1920 struct srp_target_port *target = ch->target;
1921
1922 if (wr_id == SRP_LAST_WR_ID) {
1923 complete(&ch->done);
1924 return;
1925 }
1926
1927 if (ch->connected && !target->qp_in_error) {
1928 if (wr_id & LOCAL_INV_WR_ID_MASK) {
1929 shost_printk(KERN_ERR, target->scsi_host, PFX
1930 "LOCAL_INV failed with status %d\n",
1931 wc_status);
1932 } else if (wr_id & FAST_REG_WR_ID_MASK) {
1933 shost_printk(KERN_ERR, target->scsi_host, PFX
1934 "FAST_REG_MR failed status %d\n",
1935 wc_status);
1936 } else {
1937 shost_printk(KERN_ERR, target->scsi_host,
1938 PFX "failed %s status %d for iu %p\n",
1939 send_err ? "send" : "receive",
1940 wc_status, (void *)(uintptr_t)wr_id);
1941 }
1942 queue_work(system_long_wq, &target->tl_err_work);
1943 }
1944 target->qp_in_error = true;
1945 }
1946
1947 static void srp_recv_completion(struct ib_cq *cq, void *ch_ptr)
1948 {
1949 struct srp_rdma_ch *ch = ch_ptr;
1950 struct ib_wc wc;
1951
1952 ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1953 while (ib_poll_cq(cq, 1, &wc) > 0) {
1954 if (likely(wc.status == IB_WC_SUCCESS)) {
1955 srp_handle_recv(ch, &wc);
1956 } else {
1957 srp_handle_qp_err(wc.wr_id, wc.status, false, ch);
1958 }
1959 }
1960 }
1961
1962 static void srp_send_completion(struct ib_cq *cq, void *ch_ptr)
1963 {
1964 struct srp_rdma_ch *ch = ch_ptr;
1965 struct ib_wc wc;
1966 struct srp_iu *iu;
1967
1968 while (ib_poll_cq(cq, 1, &wc) > 0) {
1969 if (likely(wc.status == IB_WC_SUCCESS)) {
1970 iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
1971 list_add(&iu->list, &ch->free_tx);
1972 } else {
1973 srp_handle_qp_err(wc.wr_id, wc.status, true, ch);
1974 }
1975 }
1976 }
1977
1978 static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1979 {
1980 struct srp_target_port *target = host_to_target(shost);
1981 struct srp_rport *rport = target->rport;
1982 struct srp_rdma_ch *ch;
1983 struct srp_request *req;
1984 struct srp_iu *iu;
1985 struct srp_cmd *cmd;
1986 struct ib_device *dev;
1987 unsigned long flags;
1988 u32 tag;
1989 u16 idx;
1990 int len, ret;
1991 const bool in_scsi_eh = !in_interrupt() && current == shost->ehandler;
1992
1993 /*
1994 * The SCSI EH thread is the only context from which srp_queuecommand()
1995 * can get invoked for blocked devices (SDEV_BLOCK /
1996 * SDEV_CREATED_BLOCK). Avoid racing with srp_reconnect_rport() by
1997 * locking the rport mutex if invoked from inside the SCSI EH.
1998 */
1999 if (in_scsi_eh)
2000 mutex_lock(&rport->mutex);
2001
2002 scmnd->result = srp_chkready(target->rport);
2003 if (unlikely(scmnd->result))
2004 goto err;
2005
2006 WARN_ON_ONCE(scmnd->request->tag < 0);
2007 tag = blk_mq_unique_tag(scmnd->request);
2008 ch = &target->ch[blk_mq_unique_tag_to_hwq(tag)];
2009 idx = blk_mq_unique_tag_to_tag(tag);
2010 WARN_ONCE(idx >= target->req_ring_size, "%s: tag %#x: idx %d >= %d\n",
2011 dev_name(&shost->shost_gendev), tag, idx,
2012 target->req_ring_size);
2013
2014 spin_lock_irqsave(&ch->lock, flags);
2015 iu = __srp_get_tx_iu(ch, SRP_IU_CMD);
2016 spin_unlock_irqrestore(&ch->lock, flags);
2017
2018 if (!iu)
2019 goto err;
2020
2021 req = &ch->req_ring[idx];
2022 dev = target->srp_host->srp_dev->dev;
2023 ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
2024 DMA_TO_DEVICE);
2025
2026 scmnd->host_scribble = (void *) req;
2027
2028 cmd = iu->buf;
2029 memset(cmd, 0, sizeof *cmd);
2030
2031 cmd->opcode = SRP_CMD;
2032 cmd->lun = cpu_to_be64((u64) scmnd->device->lun << 48);
2033 cmd->tag = tag;
2034 memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
2035
2036 req->scmnd = scmnd;
2037 req->cmd = iu;
2038
2039 len = srp_map_data(scmnd, ch, req);
2040 if (len < 0) {
2041 shost_printk(KERN_ERR, target->scsi_host,
2042 PFX "Failed to map data (%d)\n", len);
2043 /*
2044 * If we ran out of memory descriptors (-ENOMEM) because an
2045 * application is queuing many requests with more than
2046 * max_pages_per_mr sg-list elements, tell the SCSI mid-layer
2047 * to reduce queue depth temporarily.
2048 */
2049 scmnd->result = len == -ENOMEM ?
2050 DID_OK << 16 | QUEUE_FULL << 1 : DID_ERROR << 16;
2051 goto err_iu;
2052 }
2053
2054 ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
2055 DMA_TO_DEVICE);
2056
2057 if (srp_post_send(ch, iu, len)) {
2058 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
2059 goto err_unmap;
2060 }
2061
2062 ret = 0;
2063
2064 unlock_rport:
2065 if (in_scsi_eh)
2066 mutex_unlock(&rport->mutex);
2067
2068 return ret;
2069
2070 err_unmap:
2071 srp_unmap_data(scmnd, ch, req);
2072
2073 err_iu:
2074 srp_put_tx_iu(ch, iu, SRP_IU_CMD);
2075
2076 /*
2077 * Avoid that the loops that iterate over the request ring can
2078 * encounter a dangling SCSI command pointer.
2079 */
2080 req->scmnd = NULL;
2081
2082 err:
2083 if (scmnd->result) {
2084 scmnd->scsi_done(scmnd);
2085 ret = 0;
2086 } else {
2087 ret = SCSI_MLQUEUE_HOST_BUSY;
2088 }
2089
2090 goto unlock_rport;
2091 }
2092
2093 /*
2094 * Note: the resources allocated in this function are freed in
2095 * srp_free_ch_ib().
2096 */
2097 static int srp_alloc_iu_bufs(struct srp_rdma_ch *ch)
2098 {
2099 struct srp_target_port *target = ch->target;
2100 int i;
2101
2102 ch->rx_ring = kcalloc(target->queue_size, sizeof(*ch->rx_ring),
2103 GFP_KERNEL);
2104 if (!ch->rx_ring)
2105 goto err_no_ring;
2106 ch->tx_ring = kcalloc(target->queue_size, sizeof(*ch->tx_ring),
2107 GFP_KERNEL);
2108 if (!ch->tx_ring)
2109 goto err_no_ring;
2110
2111 for (i = 0; i < target->queue_size; ++i) {
2112 ch->rx_ring[i] = srp_alloc_iu(target->srp_host,
2113 ch->max_ti_iu_len,
2114 GFP_KERNEL, DMA_FROM_DEVICE);
2115 if (!ch->rx_ring[i])
2116 goto err;
2117 }
2118
2119 for (i = 0; i < target->queue_size; ++i) {
2120 ch->tx_ring[i] = srp_alloc_iu(target->srp_host,
2121 target->max_iu_len,
2122 GFP_KERNEL, DMA_TO_DEVICE);
2123 if (!ch->tx_ring[i])
2124 goto err;
2125
2126 list_add(&ch->tx_ring[i]->list, &ch->free_tx);
2127 }
2128
2129 return 0;
2130
2131 err:
2132 for (i = 0; i < target->queue_size; ++i) {
2133 srp_free_iu(target->srp_host, ch->rx_ring[i]);
2134 srp_free_iu(target->srp_host, ch->tx_ring[i]);
2135 }
2136
2137
2138 err_no_ring:
2139 kfree(ch->tx_ring);
2140 ch->tx_ring = NULL;
2141 kfree(ch->rx_ring);
2142 ch->rx_ring = NULL;
2143
2144 return -ENOMEM;
2145 }
2146
2147 static uint32_t srp_compute_rq_tmo(struct ib_qp_attr *qp_attr, int attr_mask)
2148 {
2149 uint64_t T_tr_ns, max_compl_time_ms;
2150 uint32_t rq_tmo_jiffies;
2151
2152 /*
2153 * According to section 11.2.4.2 in the IBTA spec (Modify Queue Pair,
2154 * table 91), both the QP timeout and the retry count have to be set
2155 * for RC QP's during the RTR to RTS transition.
2156 */
2157 WARN_ON_ONCE((attr_mask & (IB_QP_TIMEOUT | IB_QP_RETRY_CNT)) !=
2158 (IB_QP_TIMEOUT | IB_QP_RETRY_CNT));
2159
2160 /*
2161 * Set target->rq_tmo_jiffies to one second more than the largest time
2162 * it can take before an error completion is generated. See also
2163 * C9-140..142 in the IBTA spec for more information about how to
2164 * convert the QP Local ACK Timeout value to nanoseconds.
2165 */
2166 T_tr_ns = 4096 * (1ULL << qp_attr->timeout);
2167 max_compl_time_ms = qp_attr->retry_cnt * 4 * T_tr_ns;
2168 do_div(max_compl_time_ms, NSEC_PER_MSEC);
2169 rq_tmo_jiffies = msecs_to_jiffies(max_compl_time_ms + 1000);
2170
2171 return rq_tmo_jiffies;
2172 }
2173
2174 static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
2175 struct srp_login_rsp *lrsp,
2176 struct srp_rdma_ch *ch)
2177 {
2178 struct srp_target_port *target = ch->target;
2179 struct ib_qp_attr *qp_attr = NULL;
2180 int attr_mask = 0;
2181 int ret;
2182 int i;
2183
2184 if (lrsp->opcode == SRP_LOGIN_RSP) {
2185 ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
2186 ch->req_lim = be32_to_cpu(lrsp->req_lim_delta);
2187
2188 /*
2189 * Reserve credits for task management so we don't
2190 * bounce requests back to the SCSI mid-layer.
2191 */
2192 target->scsi_host->can_queue
2193 = min(ch->req_lim - SRP_TSK_MGMT_SQ_SIZE,
2194 target->scsi_host->can_queue);
2195 target->scsi_host->cmd_per_lun
2196 = min_t(int, target->scsi_host->can_queue,
2197 target->scsi_host->cmd_per_lun);
2198 } else {
2199 shost_printk(KERN_WARNING, target->scsi_host,
2200 PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
2201 ret = -ECONNRESET;
2202 goto error;
2203 }
2204
2205 if (!ch->rx_ring) {
2206 ret = srp_alloc_iu_bufs(ch);
2207 if (ret)
2208 goto error;
2209 }
2210
2211 ret = -ENOMEM;
2212 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
2213 if (!qp_attr)
2214 goto error;
2215
2216 qp_attr->qp_state = IB_QPS_RTR;
2217 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
2218 if (ret)
2219 goto error_free;
2220
2221 ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2222 if (ret)
2223 goto error_free;
2224
2225 for (i = 0; i < target->queue_size; i++) {
2226 struct srp_iu *iu = ch->rx_ring[i];
2227
2228 ret = srp_post_recv(ch, iu);
2229 if (ret)
2230 goto error_free;
2231 }
2232
2233 qp_attr->qp_state = IB_QPS_RTS;
2234 ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
2235 if (ret)
2236 goto error_free;
2237
2238 target->rq_tmo_jiffies = srp_compute_rq_tmo(qp_attr, attr_mask);
2239
2240 ret = ib_modify_qp(ch->qp, qp_attr, attr_mask);
2241 if (ret)
2242 goto error_free;
2243
2244 ret = ib_send_cm_rtu(cm_id, NULL, 0);
2245
2246 error_free:
2247 kfree(qp_attr);
2248
2249 error:
2250 ch->status = ret;
2251 }
2252
2253 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
2254 struct ib_cm_event *event,
2255 struct srp_rdma_ch *ch)
2256 {
2257 struct srp_target_port *target = ch->target;
2258 struct Scsi_Host *shost = target->scsi_host;
2259 struct ib_class_port_info *cpi;
2260 int opcode;
2261
2262 switch (event->param.rej_rcvd.reason) {
2263 case IB_CM_REJ_PORT_CM_REDIRECT:
2264 cpi = event->param.rej_rcvd.ari;
2265 ch->path.dlid = cpi->redirect_lid;
2266 ch->path.pkey = cpi->redirect_pkey;
2267 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
2268 memcpy(ch->path.dgid.raw, cpi->redirect_gid, 16);
2269
2270 ch->status = ch->path.dlid ?
2271 SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
2272 break;
2273
2274 case IB_CM_REJ_PORT_REDIRECT:
2275 if (srp_target_is_topspin(target)) {
2276 /*
2277 * Topspin/Cisco SRP gateways incorrectly send
2278 * reject reason code 25 when they mean 24
2279 * (port redirect).
2280 */
2281 memcpy(ch->path.dgid.raw,
2282 event->param.rej_rcvd.ari, 16);
2283
2284 shost_printk(KERN_DEBUG, shost,
2285 PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
2286 be64_to_cpu(ch->path.dgid.global.subnet_prefix),
2287 be64_to_cpu(ch->path.dgid.global.interface_id));
2288
2289 ch->status = SRP_PORT_REDIRECT;
2290 } else {
2291 shost_printk(KERN_WARNING, shost,
2292 " REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
2293 ch->status = -ECONNRESET;
2294 }
2295 break;
2296
2297 case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
2298 shost_printk(KERN_WARNING, shost,
2299 " REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
2300 ch->status = -ECONNRESET;
2301 break;
2302
2303 case IB_CM_REJ_CONSUMER_DEFINED:
2304 opcode = *(u8 *) event->private_data;
2305 if (opcode == SRP_LOGIN_REJ) {
2306 struct srp_login_rej *rej = event->private_data;
2307 u32 reason = be32_to_cpu(rej->reason);
2308
2309 if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
2310 shost_printk(KERN_WARNING, shost,
2311 PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
2312 else
2313 shost_printk(KERN_WARNING, shost, PFX
2314 "SRP LOGIN from %pI6 to %pI6 REJECTED, reason 0x%08x\n",
2315 target->sgid.raw,
2316 target->orig_dgid.raw, reason);
2317 } else
2318 shost_printk(KERN_WARNING, shost,
2319 " REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
2320 " opcode 0x%02x\n", opcode);
2321 ch->status = -ECONNRESET;
2322 break;
2323
2324 case IB_CM_REJ_STALE_CONN:
2325 shost_printk(KERN_WARNING, shost, " REJ reason: stale connection\n");
2326 ch->status = SRP_STALE_CONN;
2327 break;
2328
2329 default:
2330 shost_printk(KERN_WARNING, shost, " REJ reason 0x%x\n",
2331 event->param.rej_rcvd.reason);
2332 ch->status = -ECONNRESET;
2333 }
2334 }
2335
2336 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
2337 {
2338 struct srp_rdma_ch *ch = cm_id->context;
2339 struct srp_target_port *target = ch->target;
2340 int comp = 0;
2341
2342 switch (event->event) {
2343 case IB_CM_REQ_ERROR:
2344 shost_printk(KERN_DEBUG, target->scsi_host,
2345 PFX "Sending CM REQ failed\n");
2346 comp = 1;
2347 ch->status = -ECONNRESET;
2348 break;
2349
2350 case IB_CM_REP_RECEIVED:
2351 comp = 1;
2352 srp_cm_rep_handler(cm_id, event->private_data, ch);
2353 break;
2354
2355 case IB_CM_REJ_RECEIVED:
2356 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
2357 comp = 1;
2358
2359 srp_cm_rej_handler(cm_id, event, ch);
2360 break;
2361
2362 case IB_CM_DREQ_RECEIVED:
2363 shost_printk(KERN_WARNING, target->scsi_host,
2364 PFX "DREQ received - connection closed\n");
2365 ch->connected = false;
2366 if (ib_send_cm_drep(cm_id, NULL, 0))
2367 shost_printk(KERN_ERR, target->scsi_host,
2368 PFX "Sending CM DREP failed\n");
2369 queue_work(system_long_wq, &target->tl_err_work);
2370 break;
2371
2372 case IB_CM_TIMEWAIT_EXIT:
2373 shost_printk(KERN_ERR, target->scsi_host,
2374 PFX "connection closed\n");
2375 comp = 1;
2376
2377 ch->status = 0;
2378 break;
2379
2380 case IB_CM_MRA_RECEIVED:
2381 case IB_CM_DREQ_ERROR:
2382 case IB_CM_DREP_RECEIVED:
2383 break;
2384
2385 default:
2386 shost_printk(KERN_WARNING, target->scsi_host,
2387 PFX "Unhandled CM event %d\n", event->event);
2388 break;
2389 }
2390
2391 if (comp)
2392 complete(&ch->done);
2393
2394 return 0;
2395 }
2396
2397 /**
2398 * srp_change_queue_depth - setting device queue depth
2399 * @sdev: scsi device struct
2400 * @qdepth: requested queue depth
2401 *
2402 * Returns queue depth.
2403 */
2404 static int
2405 srp_change_queue_depth(struct scsi_device *sdev, int qdepth)
2406 {
2407 if (!sdev->tagged_supported)
2408 qdepth = 1;
2409 return scsi_change_queue_depth(sdev, qdepth);
2410 }
2411
2412 static int srp_send_tsk_mgmt(struct srp_rdma_ch *ch, u64 req_tag,
2413 unsigned int lun, u8 func)
2414 {
2415 struct srp_target_port *target = ch->target;
2416 struct srp_rport *rport = target->rport;
2417 struct ib_device *dev = target->srp_host->srp_dev->dev;
2418 struct srp_iu *iu;
2419 struct srp_tsk_mgmt *tsk_mgmt;
2420
2421 if (!ch->connected || target->qp_in_error)
2422 return -1;
2423
2424 init_completion(&ch->tsk_mgmt_done);
2425
2426 /*
2427 * Lock the rport mutex to avoid that srp_create_ch_ib() is
2428 * invoked while a task management function is being sent.
2429 */
2430 mutex_lock(&rport->mutex);
2431 spin_lock_irq(&ch->lock);
2432 iu = __srp_get_tx_iu(ch, SRP_IU_TSK_MGMT);
2433 spin_unlock_irq(&ch->lock);
2434
2435 if (!iu) {
2436 mutex_unlock(&rport->mutex);
2437
2438 return -1;
2439 }
2440
2441 ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
2442 DMA_TO_DEVICE);
2443 tsk_mgmt = iu->buf;
2444 memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
2445
2446 tsk_mgmt->opcode = SRP_TSK_MGMT;
2447 tsk_mgmt->lun = cpu_to_be64((u64) lun << 48);
2448 tsk_mgmt->tag = req_tag | SRP_TAG_TSK_MGMT;
2449 tsk_mgmt->tsk_mgmt_func = func;
2450 tsk_mgmt->task_tag = req_tag;
2451
2452 ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
2453 DMA_TO_DEVICE);
2454 if (srp_post_send(ch, iu, sizeof(*tsk_mgmt))) {
2455 srp_put_tx_iu(ch, iu, SRP_IU_TSK_MGMT);
2456 mutex_unlock(&rport->mutex);
2457
2458 return -1;
2459 }
2460 mutex_unlock(&rport->mutex);
2461
2462 if (!wait_for_completion_timeout(&ch->tsk_mgmt_done,
2463 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
2464 return -1;
2465
2466 return 0;
2467 }
2468
2469 static int srp_abort(struct scsi_cmnd *scmnd)
2470 {
2471 struct srp_target_port *target = host_to_target(scmnd->device->host);
2472 struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
2473 u32 tag;
2474 u16 ch_idx;
2475 struct srp_rdma_ch *ch;
2476 int ret;
2477
2478 shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
2479
2480 if (!req)
2481 return SUCCESS;
2482 tag = blk_mq_unique_tag(scmnd->request);
2483 ch_idx = blk_mq_unique_tag_to_hwq(tag);
2484 if (WARN_ON_ONCE(ch_idx >= target->ch_count))
2485 return SUCCESS;
2486 ch = &target->ch[ch_idx];
2487 if (!srp_claim_req(ch, req, NULL, scmnd))
2488 return SUCCESS;
2489 shost_printk(KERN_ERR, target->scsi_host,
2490 "Sending SRP abort for tag %#x\n", tag);
2491 if (srp_send_tsk_mgmt(ch, tag, scmnd->device->lun,
2492 SRP_TSK_ABORT_TASK) == 0)
2493 ret = SUCCESS;
2494 else if (target->rport->state == SRP_RPORT_LOST)
2495 ret = FAST_IO_FAIL;
2496 else
2497 ret = FAILED;
2498 srp_free_req(ch, req, scmnd, 0);
2499 scmnd->result = DID_ABORT << 16;
2500 scmnd->scsi_done(scmnd);
2501
2502 return ret;
2503 }
2504
2505 static int srp_reset_device(struct scsi_cmnd *scmnd)
2506 {
2507 struct srp_target_port *target = host_to_target(scmnd->device->host);
2508 struct srp_rdma_ch *ch;
2509 int i;
2510
2511 shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
2512
2513 ch = &target->ch[0];
2514 if (srp_send_tsk_mgmt(ch, SRP_TAG_NO_REQ, scmnd->device->lun,
2515 SRP_TSK_LUN_RESET))
2516 return FAILED;
2517 if (ch->tsk_mgmt_status)
2518 return FAILED;
2519
2520 for (i = 0; i < target->ch_count; i++) {
2521 ch = &target->ch[i];
2522 for (i = 0; i < target->req_ring_size; ++i) {
2523 struct srp_request *req = &ch->req_ring[i];
2524
2525 srp_finish_req(ch, req, scmnd->device, DID_RESET << 16);
2526 }
2527 }
2528
2529 return SUCCESS;
2530 }
2531
2532 static int srp_reset_host(struct scsi_cmnd *scmnd)
2533 {
2534 struct srp_target_port *target = host_to_target(scmnd->device->host);
2535
2536 shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
2537
2538 return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
2539 }
2540
2541 static int srp_slave_configure(struct scsi_device *sdev)
2542 {
2543 struct Scsi_Host *shost = sdev->host;
2544 struct srp_target_port *target = host_to_target(shost);
2545 struct request_queue *q = sdev->request_queue;
2546 unsigned long timeout;
2547
2548 if (sdev->type == TYPE_DISK) {
2549 timeout = max_t(unsigned, 30 * HZ, target->rq_tmo_jiffies);
2550 blk_queue_rq_timeout(q, timeout);
2551 }
2552
2553 return 0;
2554 }
2555
2556 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
2557 char *buf)
2558 {
2559 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2560
2561 return sprintf(buf, "0x%016llx\n",
2562 (unsigned long long) be64_to_cpu(target->id_ext));
2563 }
2564
2565 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
2566 char *buf)
2567 {
2568 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2569
2570 return sprintf(buf, "0x%016llx\n",
2571 (unsigned long long) be64_to_cpu(target->ioc_guid));
2572 }
2573
2574 static ssize_t show_service_id(struct device *dev,
2575 struct device_attribute *attr, char *buf)
2576 {
2577 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2578
2579 return sprintf(buf, "0x%016llx\n",
2580 (unsigned long long) be64_to_cpu(target->service_id));
2581 }
2582
2583 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
2584 char *buf)
2585 {
2586 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2587
2588 return sprintf(buf, "0x%04x\n", be16_to_cpu(target->pkey));
2589 }
2590
2591 static ssize_t show_sgid(struct device *dev, struct device_attribute *attr,
2592 char *buf)
2593 {
2594 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2595
2596 return sprintf(buf, "%pI6\n", target->sgid.raw);
2597 }
2598
2599 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
2600 char *buf)
2601 {
2602 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2603 struct srp_rdma_ch *ch = &target->ch[0];
2604
2605 return sprintf(buf, "%pI6\n", ch->path.dgid.raw);
2606 }
2607
2608 static ssize_t show_orig_dgid(struct device *dev,
2609 struct device_attribute *attr, char *buf)
2610 {
2611 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2612
2613 return sprintf(buf, "%pI6\n", target->orig_dgid.raw);
2614 }
2615
2616 static ssize_t show_req_lim(struct device *dev,
2617 struct device_attribute *attr, char *buf)
2618 {
2619 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2620 struct srp_rdma_ch *ch;
2621 int i, req_lim = INT_MAX;
2622
2623 for (i = 0; i < target->ch_count; i++) {
2624 ch = &target->ch[i];
2625 req_lim = min(req_lim, ch->req_lim);
2626 }
2627 return sprintf(buf, "%d\n", req_lim);
2628 }
2629
2630 static ssize_t show_zero_req_lim(struct device *dev,
2631 struct device_attribute *attr, char *buf)
2632 {
2633 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2634
2635 return sprintf(buf, "%d\n", target->zero_req_lim);
2636 }
2637
2638 static ssize_t show_local_ib_port(struct device *dev,
2639 struct device_attribute *attr, char *buf)
2640 {
2641 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2642
2643 return sprintf(buf, "%d\n", target->srp_host->port);
2644 }
2645
2646 static ssize_t show_local_ib_device(struct device *dev,
2647 struct device_attribute *attr, char *buf)
2648 {
2649 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2650
2651 return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
2652 }
2653
2654 static ssize_t show_ch_count(struct device *dev, struct device_attribute *attr,
2655 char *buf)
2656 {
2657 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2658
2659 return sprintf(buf, "%d\n", target->ch_count);
2660 }
2661
2662 static ssize_t show_comp_vector(struct device *dev,
2663 struct device_attribute *attr, char *buf)
2664 {
2665 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2666
2667 return sprintf(buf, "%d\n", target->comp_vector);
2668 }
2669
2670 static ssize_t show_tl_retry_count(struct device *dev,
2671 struct device_attribute *attr, char *buf)
2672 {
2673 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2674
2675 return sprintf(buf, "%d\n", target->tl_retry_count);
2676 }
2677
2678 static ssize_t show_cmd_sg_entries(struct device *dev,
2679 struct device_attribute *attr, char *buf)
2680 {
2681 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2682
2683 return sprintf(buf, "%u\n", target->cmd_sg_cnt);
2684 }
2685
2686 static ssize_t show_allow_ext_sg(struct device *dev,
2687 struct device_attribute *attr, char *buf)
2688 {
2689 struct srp_target_port *target = host_to_target(class_to_shost(dev));
2690
2691 return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
2692 }
2693
2694 static DEVICE_ATTR(id_ext, S_IRUGO, show_id_ext, NULL);
2695 static DEVICE_ATTR(ioc_guid, S_IRUGO, show_ioc_guid, NULL);
2696 static DEVICE_ATTR(service_id, S_IRUGO, show_service_id, NULL);
2697 static DEVICE_ATTR(pkey, S_IRUGO, show_pkey, NULL);
2698 static DEVICE_ATTR(sgid, S_IRUGO, show_sgid, NULL);
2699 static DEVICE_ATTR(dgid, S_IRUGO, show_dgid, NULL);
2700 static DEVICE_ATTR(orig_dgid, S_IRUGO, show_orig_dgid, NULL);
2701 static DEVICE_ATTR(req_lim, S_IRUGO, show_req_lim, NULL);
2702 static DEVICE_ATTR(zero_req_lim, S_IRUGO, show_zero_req_lim, NULL);
2703 static DEVICE_ATTR(local_ib_port, S_IRUGO, show_local_ib_port, NULL);
2704 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
2705 static DEVICE_ATTR(ch_count, S_IRUGO, show_ch_count, NULL);
2706 static DEVICE_ATTR(comp_vector, S_IRUGO, show_comp_vector, NULL);
2707 static DEVICE_ATTR(tl_retry_count, S_IRUGO, show_tl_retry_count, NULL);
2708 static DEVICE_ATTR(cmd_sg_entries, S_IRUGO, show_cmd_sg_entries, NULL);
2709 static DEVICE_ATTR(allow_ext_sg, S_IRUGO, show_allow_ext_sg, NULL);
2710
2711 static struct device_attribute *srp_host_attrs[] = {
2712 &dev_attr_id_ext,
2713 &dev_attr_ioc_guid,
2714 &dev_attr_service_id,
2715 &dev_attr_pkey,
2716 &dev_attr_sgid,
2717 &dev_attr_dgid,
2718 &dev_attr_orig_dgid,
2719 &dev_attr_req_lim,
2720 &dev_attr_zero_req_lim,
2721 &dev_attr_local_ib_port,
2722 &dev_attr_local_ib_device,
2723 &dev_attr_ch_count,
2724 &dev_attr_comp_vector,
2725 &dev_attr_tl_retry_count,
2726 &dev_attr_cmd_sg_entries,
2727 &dev_attr_allow_ext_sg,
2728 NULL
2729 };
2730
2731 static struct scsi_host_template srp_template = {
2732 .module = THIS_MODULE,
2733 .name = "InfiniBand SRP initiator",
2734 .proc_name = DRV_NAME,
2735 .slave_configure = srp_slave_configure,
2736 .info = srp_target_info,
2737 .queuecommand = srp_queuecommand,
2738 .change_queue_depth = srp_change_queue_depth,
2739 .eh_abort_handler = srp_abort,
2740 .eh_device_reset_handler = srp_reset_device,
2741 .eh_host_reset_handler = srp_reset_host,
2742 .skip_settle_delay = true,
2743 .sg_tablesize = SRP_DEF_SG_TABLESIZE,
2744 .can_queue = SRP_DEFAULT_CMD_SQ_SIZE,
2745 .this_id = -1,
2746 .cmd_per_lun = SRP_DEFAULT_CMD_SQ_SIZE,
2747 .use_clustering = ENABLE_CLUSTERING,
2748 .shost_attrs = srp_host_attrs,
2749 .use_blk_tags = 1,
2750 .track_queue_depth = 1,
2751 };
2752
2753 static int srp_sdev_count(struct Scsi_Host *host)
2754 {
2755 struct scsi_device *sdev;
2756 int c = 0;
2757
2758 shost_for_each_device(sdev, host)
2759 c++;
2760
2761 return c;
2762 }
2763
2764 /*
2765 * Return values:
2766 * < 0 upon failure. Caller is responsible for SRP target port cleanup.
2767 * 0 and target->state == SRP_TARGET_REMOVED if asynchronous target port
2768 * removal has been scheduled.
2769 * 0 and target->state != SRP_TARGET_REMOVED upon success.
2770 */
2771 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
2772 {
2773 struct srp_rport_identifiers ids;
2774 struct srp_rport *rport;
2775
2776 target->state = SRP_TARGET_SCANNING;
2777 sprintf(target->target_name, "SRP.T10:%016llX",
2778 (unsigned long long) be64_to_cpu(target->id_ext));
2779
2780 if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
2781 return -ENODEV;
2782
2783 memcpy(ids.port_id, &target->id_ext, 8);
2784 memcpy(ids.port_id + 8, &target->ioc_guid, 8);
2785 ids.roles = SRP_RPORT_ROLE_TARGET;
2786 rport = srp_rport_add(target->scsi_host, &ids);
2787 if (IS_ERR(rport)) {
2788 scsi_remove_host(target->scsi_host);
2789 return PTR_ERR(rport);
2790 }
2791
2792 rport->lld_data = target;
2793 target->rport = rport;
2794
2795 spin_lock(&host->target_lock);
2796 list_add_tail(&target->list, &host->target_list);
2797 spin_unlock(&host->target_lock);
2798
2799 scsi_scan_target(&target->scsi_host->shost_gendev,
2800 0, target->scsi_id, SCAN_WILD_CARD, 0);
2801
2802 if (srp_connected_ch(target) < target->ch_count ||
2803 target->qp_in_error) {
2804 shost_printk(KERN_INFO, target->scsi_host,
2805 PFX "SCSI scan failed - removing SCSI host\n");
2806 srp_queue_remove_work(target);
2807 goto out;
2808 }
2809
2810 pr_debug(PFX "%s: SCSI scan succeeded - detected %d LUNs\n",
2811 dev_name(&target->scsi_host->shost_gendev),
2812 srp_sdev_count(target->scsi_host));
2813
2814 spin_lock_irq(&target->lock);
2815 if (target->state == SRP_TARGET_SCANNING)
2816 target->state = SRP_TARGET_LIVE;
2817 spin_unlock_irq(&target->lock);
2818
2819 out:
2820 return 0;
2821 }
2822
2823 static void srp_release_dev(struct device *dev)
2824 {
2825 struct srp_host *host =
2826 container_of(dev, struct srp_host, dev);
2827
2828 complete(&host->released);
2829 }
2830
2831 static struct class srp_class = {
2832 .name = "infiniband_srp",
2833 .dev_release = srp_release_dev
2834 };
2835
2836 /**
2837 * srp_conn_unique() - check whether the connection to a target is unique
2838 * @host: SRP host.
2839 * @target: SRP target port.
2840 */
2841 static bool srp_conn_unique(struct srp_host *host,
2842 struct srp_target_port *target)
2843 {
2844 struct srp_target_port *t;
2845 bool ret = false;
2846
2847 if (target->state == SRP_TARGET_REMOVED)
2848 goto out;
2849
2850 ret = true;
2851
2852 spin_lock(&host->target_lock);
2853 list_for_each_entry(t, &host->target_list, list) {
2854 if (t != target &&
2855 target->id_ext == t->id_ext &&
2856 target->ioc_guid == t->ioc_guid &&
2857 target->initiator_ext == t->initiator_ext) {
2858 ret = false;
2859 break;
2860 }
2861 }
2862 spin_unlock(&host->target_lock);
2863
2864 out:
2865 return ret;
2866 }
2867
2868 /*
2869 * Target ports are added by writing
2870 *
2871 * id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
2872 * pkey=<P_Key>,service_id=<service ID>
2873 *
2874 * to the add_target sysfs attribute.
2875 */
2876 enum {
2877 SRP_OPT_ERR = 0,
2878 SRP_OPT_ID_EXT = 1 << 0,
2879 SRP_OPT_IOC_GUID = 1 << 1,
2880 SRP_OPT_DGID = 1 << 2,
2881 SRP_OPT_PKEY = 1 << 3,
2882 SRP_OPT_SERVICE_ID = 1 << 4,
2883 SRP_OPT_MAX_SECT = 1 << 5,
2884 SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
2885 SRP_OPT_IO_CLASS = 1 << 7,
2886 SRP_OPT_INITIATOR_EXT = 1 << 8,
2887 SRP_OPT_CMD_SG_ENTRIES = 1 << 9,
2888 SRP_OPT_ALLOW_EXT_SG = 1 << 10,
2889 SRP_OPT_SG_TABLESIZE = 1 << 11,
2890 SRP_OPT_COMP_VECTOR = 1 << 12,
2891 SRP_OPT_TL_RETRY_COUNT = 1 << 13,
2892 SRP_OPT_QUEUE_SIZE = 1 << 14,
2893 SRP_OPT_ALL = (SRP_OPT_ID_EXT |
2894 SRP_OPT_IOC_GUID |
2895 SRP_OPT_DGID |
2896 SRP_OPT_PKEY |
2897 SRP_OPT_SERVICE_ID),
2898 };
2899
2900 static const match_table_t srp_opt_tokens = {
2901 { SRP_OPT_ID_EXT, "id_ext=%s" },
2902 { SRP_OPT_IOC_GUID, "ioc_guid=%s" },
2903 { SRP_OPT_DGID, "dgid=%s" },
2904 { SRP_OPT_PKEY, "pkey=%x" },
2905 { SRP_OPT_SERVICE_ID, "service_id=%s" },
2906 { SRP_OPT_MAX_SECT, "max_sect=%d" },
2907 { SRP_OPT_MAX_CMD_PER_LUN, "max_cmd_per_lun=%d" },
2908 { SRP_OPT_IO_CLASS, "io_class=%x" },
2909 { SRP_OPT_INITIATOR_EXT, "initiator_ext=%s" },
2910 { SRP_OPT_CMD_SG_ENTRIES, "cmd_sg_entries=%u" },
2911 { SRP_OPT_ALLOW_EXT_SG, "allow_ext_sg=%u" },
2912 { SRP_OPT_SG_TABLESIZE, "sg_tablesize=%u" },
2913 { SRP_OPT_COMP_VECTOR, "comp_vector=%u" },
2914 { SRP_OPT_TL_RETRY_COUNT, "tl_retry_count=%u" },
2915 { SRP_OPT_QUEUE_SIZE, "queue_size=%d" },
2916 { SRP_OPT_ERR, NULL }
2917 };
2918
2919 static int srp_parse_options(const char *buf, struct srp_target_port *target)
2920 {
2921 char *options, *sep_opt;
2922 char *p;
2923 char dgid[3];
2924 substring_t args[MAX_OPT_ARGS];
2925 int opt_mask = 0;
2926 int token;
2927 int ret = -EINVAL;
2928 int i;
2929
2930 options = kstrdup(buf, GFP_KERNEL);
2931 if (!options)
2932 return -ENOMEM;
2933
2934 sep_opt = options;
2935 while ((p = strsep(&sep_opt, ",\n")) != NULL) {
2936 if (!*p)
2937 continue;
2938
2939 token = match_token(p, srp_opt_tokens, args);
2940 opt_mask |= token;
2941
2942 switch (token) {
2943 case SRP_OPT_ID_EXT:
2944 p = match_strdup(args);
2945 if (!p) {
2946 ret = -ENOMEM;
2947 goto out;
2948 }
2949 target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
2950 kfree(p);
2951 break;
2952
2953 case SRP_OPT_IOC_GUID:
2954 p = match_strdup(args);
2955 if (!p) {
2956 ret = -ENOMEM;
2957 goto out;
2958 }
2959 target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
2960 kfree(p);
2961 break;
2962
2963 case SRP_OPT_DGID:
2964 p = match_strdup(args);
2965 if (!p) {
2966 ret = -ENOMEM;
2967 goto out;
2968 }
2969 if (strlen(p) != 32) {
2970 pr_warn("bad dest GID parameter '%s'\n", p);
2971 kfree(p);
2972 goto out;
2973 }
2974
2975 for (i = 0; i < 16; ++i) {
2976 strlcpy(dgid, p + i * 2, sizeof(dgid));
2977 if (sscanf(dgid, "%hhx",
2978 &target->orig_dgid.raw[i]) < 1) {
2979 ret = -EINVAL;
2980 kfree(p);
2981 goto out;
2982 }
2983 }
2984 kfree(p);
2985 break;
2986
2987 case SRP_OPT_PKEY:
2988 if (match_hex(args, &token)) {
2989 pr_warn("bad P_Key parameter '%s'\n", p);
2990 goto out;
2991 }
2992 target->pkey = cpu_to_be16(token);
2993 break;
2994
2995 case SRP_OPT_SERVICE_ID:
2996 p = match_strdup(args);
2997 if (!p) {
2998 ret = -ENOMEM;
2999 goto out;
3000 }
3001 target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
3002 kfree(p);
3003 break;
3004
3005 case SRP_OPT_MAX_SECT:
3006 if (match_int(args, &token)) {
3007 pr_warn("bad max sect parameter '%s'\n", p);
3008 goto out;
3009 }
3010 target->scsi_host->max_sectors = token;
3011 break;
3012
3013 case SRP_OPT_QUEUE_SIZE:
3014 if (match_int(args, &token) || token < 1) {
3015 pr_warn("bad queue_size parameter '%s'\n", p);
3016 goto out;
3017 }
3018 target->scsi_host->can_queue = token;
3019 target->queue_size = token + SRP_RSP_SQ_SIZE +
3020 SRP_TSK_MGMT_SQ_SIZE;
3021 if (!(opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
3022 target->scsi_host->cmd_per_lun = token;
3023 break;
3024
3025 case SRP_OPT_MAX_CMD_PER_LUN:
3026 if (match_int(args, &token) || token < 1) {
3027 pr_warn("bad max cmd_per_lun parameter '%s'\n",
3028 p);
3029 goto out;
3030 }
3031 target->scsi_host->cmd_per_lun = token;
3032 break;
3033
3034 case SRP_OPT_IO_CLASS:
3035 if (match_hex(args, &token)) {
3036 pr_warn("bad IO class parameter '%s'\n", p);
3037 goto out;
3038 }
3039 if (token != SRP_REV10_IB_IO_CLASS &&
3040 token != SRP_REV16A_IB_IO_CLASS) {
3041 pr_warn("unknown IO class parameter value %x specified (use %x or %x).\n",
3042 token, SRP_REV10_IB_IO_CLASS,
3043 SRP_REV16A_IB_IO_CLASS);
3044 goto out;
3045 }
3046 target->io_class = token;
3047 break;
3048
3049 case SRP_OPT_INITIATOR_EXT:
3050 p = match_strdup(args);
3051 if (!p) {
3052 ret = -ENOMEM;
3053 goto out;
3054 }
3055 target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
3056 kfree(p);
3057 break;
3058
3059 case SRP_OPT_CMD_SG_ENTRIES:
3060 if (match_int(args, &token) || token < 1 || token > 255) {
3061 pr_warn("bad max cmd_sg_entries parameter '%s'\n",
3062 p);
3063 goto out;
3064 }
3065 target->cmd_sg_cnt = token;
3066 break;
3067
3068 case SRP_OPT_ALLOW_EXT_SG:
3069 if (match_int(args, &token)) {
3070 pr_warn("bad allow_ext_sg parameter '%s'\n", p);
3071 goto out;
3072 }
3073 target->allow_ext_sg = !!token;
3074 break;
3075
3076 case SRP_OPT_SG_TABLESIZE:
3077 if (match_int(args, &token) || token < 1 ||
3078 token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
3079 pr_warn("bad max sg_tablesize parameter '%s'\n",
3080 p);
3081 goto out;
3082 }
3083 target->sg_tablesize = token;
3084 break;
3085
3086 case SRP_OPT_COMP_VECTOR:
3087 if (match_int(args, &token) || token < 0) {
3088 pr_warn("bad comp_vector parameter '%s'\n", p);
3089 goto out;
3090 }
3091 target->comp_vector = token;
3092 break;
3093
3094 case SRP_OPT_TL_RETRY_COUNT:
3095 if (match_int(args, &token) || token < 2 || token > 7) {
3096 pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n",
3097 p);
3098 goto out;
3099 }
3100 target->tl_retry_count = token;
3101 break;
3102
3103 default:
3104 pr_warn("unknown parameter or missing value '%s' in target creation request\n",
3105 p);
3106 goto out;
3107 }
3108 }
3109
3110 if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
3111 ret = 0;
3112 else
3113 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
3114 if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
3115 !(srp_opt_tokens[i].token & opt_mask))
3116 pr_warn("target creation request is missing parameter '%s'\n",
3117 srp_opt_tokens[i].pattern);
3118
3119 if (target->scsi_host->cmd_per_lun > target->scsi_host->can_queue
3120 && (opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
3121 pr_warn("cmd_per_lun = %d > queue_size = %d\n",
3122 target->scsi_host->cmd_per_lun,
3123 target->scsi_host->can_queue);
3124
3125 out:
3126 kfree(options);
3127 return ret;
3128 }
3129
3130 static ssize_t srp_create_target(struct device *dev,
3131 struct device_attribute *attr,
3132 const char *buf, size_t count)
3133 {
3134 struct srp_host *host =
3135 container_of(dev, struct srp_host, dev);
3136 struct Scsi_Host *target_host;
3137 struct srp_target_port *target;
3138 struct srp_rdma_ch *ch;
3139 struct srp_device *srp_dev = host->srp_dev;
3140 struct ib_device *ibdev = srp_dev->dev;
3141 int ret, node_idx, node, cpu, i;
3142 bool multich = false;
3143
3144 target_host = scsi_host_alloc(&srp_template,
3145 sizeof (struct srp_target_port));
3146 if (!target_host)
3147 return -ENOMEM;
3148
3149 target_host->transportt = ib_srp_transport_template;
3150 target_host->max_channel = 0;
3151 target_host->max_id = 1;
3152 target_host->max_lun = SRP_MAX_LUN;
3153 target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
3154
3155 target = host_to_target(target_host);
3156
3157 target->io_class = SRP_REV16A_IB_IO_CLASS;
3158 target->scsi_host = target_host;
3159 target->srp_host = host;
3160 target->lkey = host->srp_dev->mr->lkey;
3161 target->rkey = host->srp_dev->mr->rkey;
3162 target->cmd_sg_cnt = cmd_sg_entries;
3163 target->sg_tablesize = indirect_sg_entries ? : cmd_sg_entries;
3164 target->allow_ext_sg = allow_ext_sg;
3165 target->tl_retry_count = 7;
3166 target->queue_size = SRP_DEFAULT_QUEUE_SIZE;
3167
3168 /*
3169 * Avoid that the SCSI host can be removed by srp_remove_target()
3170 * before this function returns.
3171 */
3172 scsi_host_get(target->scsi_host);
3173
3174 mutex_lock(&host->add_target_mutex);
3175
3176 ret = srp_parse_options(buf, target);
3177 if (ret)
3178 goto out;
3179
3180 ret = scsi_init_shared_tag_map(target_host, target_host->can_queue);
3181 if (ret)
3182 goto out;
3183
3184 target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;
3185
3186 if (!srp_conn_unique(target->srp_host, target)) {
3187 shost_printk(KERN_INFO, target->scsi_host,
3188 PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;initiator_ext=%016llx\n",
3189 be64_to_cpu(target->id_ext),
3190 be64_to_cpu(target->ioc_guid),
3191 be64_to_cpu(target->initiator_ext));
3192 ret = -EEXIST;
3193 goto out;
3194 }
3195
3196 if (!srp_dev->has_fmr && !srp_dev->has_fr && !target->allow_ext_sg &&
3197 target->cmd_sg_cnt < target->sg_tablesize) {
3198 pr_warn("No MR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
3199 target->sg_tablesize = target->cmd_sg_cnt;
3200 }
3201
3202 target_host->sg_tablesize = target->sg_tablesize;
3203 target->indirect_size = target->sg_tablesize *
3204 sizeof (struct srp_direct_buf);
3205 target->max_iu_len = sizeof (struct srp_cmd) +
3206 sizeof (struct srp_indirect_buf) +
3207 target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
3208
3209 INIT_WORK(&target->tl_err_work, srp_tl_err_work);
3210 INIT_WORK(&target->remove_work, srp_remove_work);
3211 spin_lock_init(&target->lock);
3212 ret = ib_query_gid(ibdev, host->port, 0, &target->sgid);
3213 if (ret)
3214 goto out;
3215
3216 ret = -ENOMEM;
3217 target->ch_count = max_t(unsigned, num_online_nodes(),
3218 min(ch_count ? :
3219 min(4 * num_online_nodes(),
3220 ibdev->num_comp_vectors),
3221 num_online_cpus()));
3222 target->ch = kcalloc(target->ch_count, sizeof(*target->ch),
3223 GFP_KERNEL);
3224 if (!target->ch)
3225 goto out;
3226
3227 node_idx = 0;
3228 for_each_online_node(node) {
3229 const int ch_start = (node_idx * target->ch_count /
3230 num_online_nodes());
3231 const int ch_end = ((node_idx + 1) * target->ch_count /
3232 num_online_nodes());
3233 const int cv_start = (node_idx * ibdev->num_comp_vectors /
3234 num_online_nodes() + target->comp_vector)
3235 % ibdev->num_comp_vectors;
3236 const int cv_end = ((node_idx + 1) * ibdev->num_comp_vectors /
3237 num_online_nodes() + target->comp_vector)
3238 % ibdev->num_comp_vectors;
3239 int cpu_idx = 0;
3240
3241 for_each_online_cpu(cpu) {
3242 if (cpu_to_node(cpu) != node)
3243 continue;
3244 if (ch_start + cpu_idx >= ch_end)
3245 continue;
3246 ch = &target->ch[ch_start + cpu_idx];
3247 ch->target = target;
3248 ch->comp_vector = cv_start == cv_end ? cv_start :
3249 cv_start + cpu_idx % (cv_end - cv_start);
3250 spin_lock_init(&ch->lock);
3251 INIT_LIST_HEAD(&ch->free_tx);
3252 ret = srp_new_cm_id(ch);
3253 if (ret)
3254 goto err_disconnect;
3255
3256 ret = srp_create_ch_ib(ch);
3257 if (ret)
3258 goto err_disconnect;
3259
3260 ret = srp_alloc_req_data(ch);
3261 if (ret)
3262 goto err_disconnect;
3263
3264 ret = srp_connect_ch(ch, multich);
3265 if (ret) {
3266 shost_printk(KERN_ERR, target->scsi_host,
3267 PFX "Connection %d/%d failed\n",
3268 ch_start + cpu_idx,
3269 target->ch_count);
3270 if (node_idx == 0 && cpu_idx == 0) {
3271 goto err_disconnect;
3272 } else {
3273 srp_free_ch_ib(target, ch);
3274 srp_free_req_data(target, ch);
3275 target->ch_count = ch - target->ch;
3276 goto connected;
3277 }
3278 }
3279
3280 multich = true;
3281 cpu_idx++;
3282 }
3283 node_idx++;
3284 }
3285
3286 connected:
3287 target->scsi_host->nr_hw_queues = target->ch_count;
3288
3289 ret = srp_add_target(host, target);
3290 if (ret)
3291 goto err_disconnect;
3292
3293 if (target->state != SRP_TARGET_REMOVED) {
3294 shost_printk(KERN_DEBUG, target->scsi_host, PFX
3295 "new target: id_ext %016llx ioc_guid %016llx pkey %04x service_id %016llx sgid %pI6 dgid %pI6\n",
3296 be64_to_cpu(target->id_ext),
3297 be64_to_cpu(target->ioc_guid),
3298 be16_to_cpu(target->pkey),
3299 be64_to_cpu(target->service_id),
3300 target->sgid.raw, target->orig_dgid.raw);
3301 }
3302
3303 ret = count;
3304
3305 out:
3306 mutex_unlock(&host->add_target_mutex);
3307
3308 scsi_host_put(target->scsi_host);
3309 if (ret < 0)
3310 scsi_host_put(target->scsi_host);
3311
3312 return ret;
3313
3314 err_disconnect:
3315 srp_disconnect_target(target);
3316
3317 for (i = 0; i < target->ch_count; i++) {
3318 ch = &target->ch[i];
3319 srp_free_ch_ib(target, ch);
3320 srp_free_req_data(target, ch);
3321 }
3322
3323 kfree(target->ch);
3324 goto out;
3325 }
3326
3327 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
3328
3329 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
3330 char *buf)
3331 {
3332 struct srp_host *host = container_of(dev, struct srp_host, dev);
3333
3334 return sprintf(buf, "%s\n", host->srp_dev->dev->name);
3335 }
3336
3337 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
3338
3339 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
3340 char *buf)
3341 {
3342 struct srp_host *host = container_of(dev, struct srp_host, dev);
3343
3344 return sprintf(buf, "%d\n", host->port);
3345 }
3346
3347 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
3348
3349 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
3350 {
3351 struct srp_host *host;
3352
3353 host = kzalloc(sizeof *host, GFP_KERNEL);
3354 if (!host)
3355 return NULL;
3356
3357 INIT_LIST_HEAD(&host->target_list);
3358 spin_lock_init(&host->target_lock);
3359 init_completion(&host->released);
3360 mutex_init(&host->add_target_mutex);
3361 host->srp_dev = device;
3362 host->port = port;
3363
3364 host->dev.class = &srp_class;
3365 host->dev.parent = device->dev->dma_device;
3366 dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
3367
3368 if (device_register(&host->dev))
3369 goto free_host;
3370 if (device_create_file(&host->dev, &dev_attr_add_target))
3371 goto err_class;
3372 if (device_create_file(&host->dev, &dev_attr_ibdev))
3373 goto err_class;
3374 if (device_create_file(&host->dev, &dev_attr_port))
3375 goto err_class;
3376
3377 return host;
3378
3379 err_class:
3380 device_unregister(&host->dev);
3381
3382 free_host:
3383 kfree(host);
3384
3385 return NULL;
3386 }
3387
3388 static void srp_add_one(struct ib_device *device)
3389 {
3390 struct srp_device *srp_dev;
3391 struct ib_device_attr *dev_attr;
3392 struct srp_host *host;
3393 int mr_page_shift, s, e, p;
3394 u64 max_pages_per_mr;
3395
3396 dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
3397 if (!dev_attr)
3398 return;
3399
3400 if (ib_query_device(device, dev_attr)) {
3401 pr_warn("Query device failed for %s\n", device->name);
3402 goto free_attr;
3403 }
3404
3405 srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
3406 if (!srp_dev)
3407 goto free_attr;
3408
3409 srp_dev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
3410 device->map_phys_fmr && device->unmap_fmr);
3411 srp_dev->has_fr = (dev_attr->device_cap_flags &
3412 IB_DEVICE_MEM_MGT_EXTENSIONS);
3413 if (!srp_dev->has_fmr && !srp_dev->has_fr)
3414 dev_warn(&device->dev, "neither FMR nor FR is supported\n");
3415
3416 srp_dev->use_fast_reg = (srp_dev->has_fr &&
3417 (!srp_dev->has_fmr || prefer_fr));
3418
3419 /*
3420 * Use the smallest page size supported by the HCA, down to a
3421 * minimum of 4096 bytes. We're unlikely to build large sglists
3422 * out of smaller entries.
3423 */
3424 mr_page_shift = max(12, ffs(dev_attr->page_size_cap) - 1);
3425 srp_dev->mr_page_size = 1 << mr_page_shift;
3426 srp_dev->mr_page_mask = ~((u64) srp_dev->mr_page_size - 1);
3427 max_pages_per_mr = dev_attr->max_mr_size;
3428 do_div(max_pages_per_mr, srp_dev->mr_page_size);
3429 srp_dev->max_pages_per_mr = min_t(u64, SRP_MAX_PAGES_PER_MR,
3430 max_pages_per_mr);
3431 if (srp_dev->use_fast_reg) {
3432 srp_dev->max_pages_per_mr =
3433 min_t(u32, srp_dev->max_pages_per_mr,
3434 dev_attr->max_fast_reg_page_list_len);
3435 }
3436 srp_dev->mr_max_size = srp_dev->mr_page_size *
3437 srp_dev->max_pages_per_mr;
3438 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",
3439 device->name, mr_page_shift, dev_attr->max_mr_size,
3440 dev_attr->max_fast_reg_page_list_len,
3441 srp_dev->max_pages_per_mr, srp_dev->mr_max_size);
3442
3443 INIT_LIST_HEAD(&srp_dev->dev_list);
3444
3445 srp_dev->dev = device;
3446 srp_dev->pd = ib_alloc_pd(device);
3447 if (IS_ERR(srp_dev->pd))
3448 goto free_dev;
3449
3450 srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
3451 IB_ACCESS_LOCAL_WRITE |
3452 IB_ACCESS_REMOTE_READ |
3453 IB_ACCESS_REMOTE_WRITE);
3454 if (IS_ERR(srp_dev->mr))
3455 goto err_pd;
3456
3457 if (device->node_type == RDMA_NODE_IB_SWITCH) {
3458 s = 0;
3459 e = 0;
3460 } else {
3461 s = 1;
3462 e = device->phys_port_cnt;
3463 }
3464
3465 for (p = s; p <= e; ++p) {
3466 host = srp_add_port(srp_dev, p);
3467 if (host)
3468 list_add_tail(&host->list, &srp_dev->dev_list);
3469 }
3470
3471 ib_set_client_data(device, &srp_client, srp_dev);
3472
3473 goto free_attr;
3474
3475 err_pd:
3476 ib_dealloc_pd(srp_dev->pd);
3477
3478 free_dev:
3479 kfree(srp_dev);
3480
3481 free_attr:
3482 kfree(dev_attr);
3483 }
3484
3485 static void srp_remove_one(struct ib_device *device)
3486 {
3487 struct srp_device *srp_dev;
3488 struct srp_host *host, *tmp_host;
3489 struct srp_target_port *target;
3490
3491 srp_dev = ib_get_client_data(device, &srp_client);
3492 if (!srp_dev)
3493 return;
3494
3495 list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
3496 device_unregister(&host->dev);
3497 /*
3498 * Wait for the sysfs entry to go away, so that no new
3499 * target ports can be created.
3500 */
3501 wait_for_completion(&host->released);
3502
3503 /*
3504 * Remove all target ports.
3505 */
3506 spin_lock(&host->target_lock);
3507 list_for_each_entry(target, &host->target_list, list)
3508 srp_queue_remove_work(target);
3509 spin_unlock(&host->target_lock);
3510
3511 /*
3512 * Wait for tl_err and target port removal tasks.
3513 */
3514 flush_workqueue(system_long_wq);
3515 flush_workqueue(srp_remove_wq);
3516
3517 kfree(host);
3518 }
3519
3520 ib_dereg_mr(srp_dev->mr);
3521 ib_dealloc_pd(srp_dev->pd);
3522
3523 kfree(srp_dev);
3524 }
3525
3526 static struct srp_function_template ib_srp_transport_functions = {
3527 .has_rport_state = true,
3528 .reset_timer_if_blocked = true,
3529 .reconnect_delay = &srp_reconnect_delay,
3530 .fast_io_fail_tmo = &srp_fast_io_fail_tmo,
3531 .dev_loss_tmo = &srp_dev_loss_tmo,
3532 .reconnect = srp_rport_reconnect,
3533 .rport_delete = srp_rport_delete,
3534 .terminate_rport_io = srp_terminate_io,
3535 };
3536
3537 static int __init srp_init_module(void)
3538 {
3539 int ret;
3540
3541 BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
3542
3543 if (srp_sg_tablesize) {
3544 pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
3545 if (!cmd_sg_entries)
3546 cmd_sg_entries = srp_sg_tablesize;
3547 }
3548
3549 if (!cmd_sg_entries)
3550 cmd_sg_entries = SRP_DEF_SG_TABLESIZE;
3551
3552 if (cmd_sg_entries > 255) {
3553 pr_warn("Clamping cmd_sg_entries to 255\n");
3554 cmd_sg_entries = 255;
3555 }
3556
3557 if (!indirect_sg_entries)
3558 indirect_sg_entries = cmd_sg_entries;
3559 else if (indirect_sg_entries < cmd_sg_entries) {
3560 pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
3561 cmd_sg_entries);
3562 indirect_sg_entries = cmd_sg_entries;
3563 }
3564
3565 srp_remove_wq = create_workqueue("srp_remove");
3566 if (!srp_remove_wq) {
3567 ret = -ENOMEM;
3568 goto out;
3569 }
3570
3571 ret = -ENOMEM;
3572 ib_srp_transport_template =
3573 srp_attach_transport(&ib_srp_transport_functions);
3574 if (!ib_srp_transport_template)
3575 goto destroy_wq;
3576
3577 ret = class_register(&srp_class);
3578 if (ret) {
3579 pr_err("couldn't register class infiniband_srp\n");
3580 goto release_tr;
3581 }
3582
3583 ib_sa_register_client(&srp_sa_client);
3584
3585 ret = ib_register_client(&srp_client);
3586 if (ret) {
3587 pr_err("couldn't register IB client\n");
3588 goto unreg_sa;
3589 }
3590
3591 out:
3592 return ret;
3593
3594 unreg_sa:
3595 ib_sa_unregister_client(&srp_sa_client);
3596 class_unregister(&srp_class);
3597
3598 release_tr:
3599 srp_release_transport(ib_srp_transport_template);
3600
3601 destroy_wq:
3602 destroy_workqueue(srp_remove_wq);
3603 goto out;
3604 }
3605
3606 static void __exit srp_cleanup_module(void)
3607 {
3608 ib_unregister_client(&srp_client);
3609 ib_sa_unregister_client(&srp_sa_client);
3610 class_unregister(&srp_class);
3611 srp_release_transport(ib_srp_transport_template);
3612 destroy_workqueue(srp_remove_wq);
3613 }
3614
3615 module_init(srp_init_module);
3616 module_exit(srp_cleanup_module);
Linux with added FPC-III support