1 /*
2  * Copyright (c) 2005 Cisco Systems.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/module.h>
34 #include <linux/init.h>
35 #include <linux/slab.h>
36 #include <linux/err.h>
37 #include <linux/string.h>
38 #include <linux/parser.h>
39 #include <linux/random.h>
40 #include <linux/jiffies.h>
41 
42 #include <asm/atomic.h>
43 
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_device.h>
46 #include <scsi/scsi_dbg.h>
47 #include <scsi/srp.h>
48 #include <scsi/scsi_transport_srp.h>
49 
50 #include "ib_srp.h"
51 
52 #define DRV_NAME	"ib_srp"
53 #define PFX		DRV_NAME ": "
54 #define DRV_VERSION	"0.2"
55 #define DRV_RELDATE	"November 1, 2005"
56 
57 MODULE_AUTHOR("Roland Dreier");
58 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
59 		   "v" DRV_VERSION " (" DRV_RELDATE ")");
60 MODULE_LICENSE("Dual BSD/GPL");
61 
62 static int srp_sg_tablesize = SRP_DEF_SG_TABLESIZE;
63 static int srp_max_iu_len;
64 
65 module_param(srp_sg_tablesize, int, 0444);
66 MODULE_PARM_DESC(srp_sg_tablesize,
67 		 "Max number of gather/scatter entries per I/O (default is 12, max 255)");
68 
69 static int topspin_workarounds = 1;
70 
71 module_param(topspin_workarounds, int, 0444);
72 MODULE_PARM_DESC(topspin_workarounds,
73 		 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
74 
75 static int mellanox_workarounds = 1;
76 
77 module_param(mellanox_workarounds, int, 0444);
78 MODULE_PARM_DESC(mellanox_workarounds,
79 		 "Enable workarounds for Mellanox SRP target bugs if != 0");
80 
81 static void srp_add_one(struct ib_device *device);
82 static void srp_remove_one(struct ib_device *device);
83 static void srp_completion(struct ib_cq *cq, void *target_ptr);
84 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
85 
86 static struct scsi_transport_template *ib_srp_transport_template;
87 
88 static struct ib_client srp_client = {
89 	.name   = "srp",
90 	.add    = srp_add_one,
91 	.remove = srp_remove_one
92 };
93 
94 static struct ib_sa_client srp_sa_client;
95 
96 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
97 {
98 	return (struct srp_target_port *) host->hostdata;
99 }
100 
101 static const char *srp_target_info(struct Scsi_Host *host)
102 {
103 	return host_to_target(host)->target_name;
104 }
105 
106 static int srp_target_is_topspin(struct srp_target_port *target)
107 {
108 	static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
109 	static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
110 
111 	return topspin_workarounds &&
112 		(!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
113 		 !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
114 }
115 
116 static int srp_target_is_mellanox(struct srp_target_port *target)
117 {
118 	static const u8 mellanox_oui[3] = { 0x00, 0x02, 0xc9 };
119 
120 	return mellanox_workarounds &&
121 		!memcmp(&target->ioc_guid, mellanox_oui, sizeof mellanox_oui);
122 }
123 
124 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
125 				   gfp_t gfp_mask,
126 				   enum dma_data_direction direction)
127 {
128 	struct srp_iu *iu;
129 
130 	iu = kmalloc(sizeof *iu, gfp_mask);
131 	if (!iu)
132 		goto out;
133 
134 	iu->buf = kzalloc(size, gfp_mask);
135 	if (!iu->buf)
136 		goto out_free_iu;
137 
138 	iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
139 				    direction);
140 	if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
141 		goto out_free_buf;
142 
143 	iu->size      = size;
144 	iu->direction = direction;
145 
146 	return iu;
147 
148 out_free_buf:
149 	kfree(iu->buf);
150 out_free_iu:
151 	kfree(iu);
152 out:
153 	return NULL;
154 }
155 
156 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
157 {
158 	if (!iu)
159 		return;
160 
161 	ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
162 			    iu->direction);
163 	kfree(iu->buf);
164 	kfree(iu);
165 }
166 
167 static void srp_qp_event(struct ib_event *event, void *context)
168 {
169 	printk(KERN_ERR PFX "QP event %d\n", event->event);
170 }
171 
172 static int srp_init_qp(struct srp_target_port *target,
173 		       struct ib_qp *qp)
174 {
175 	struct ib_qp_attr *attr;
176 	int ret;
177 
178 	attr = kmalloc(sizeof *attr, GFP_KERNEL);
179 	if (!attr)
180 		return -ENOMEM;
181 
182 	ret = ib_find_pkey(target->srp_host->srp_dev->dev,
183 			   target->srp_host->port,
184 			   be16_to_cpu(target->path.pkey),
185 			   &attr->pkey_index);
186 	if (ret)
187 		goto out;
188 
189 	attr->qp_state        = IB_QPS_INIT;
190 	attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
191 				    IB_ACCESS_REMOTE_WRITE);
192 	attr->port_num        = target->srp_host->port;
193 
194 	ret = ib_modify_qp(qp, attr,
195 			   IB_QP_STATE		|
196 			   IB_QP_PKEY_INDEX	|
197 			   IB_QP_ACCESS_FLAGS	|
198 			   IB_QP_PORT);
199 
200 out:
201 	kfree(attr);
202 	return ret;
203 }
204 
205 static int srp_new_cm_id(struct srp_target_port *target)
206 {
207 	struct ib_cm_id *new_cm_id;
208 
209 	new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
210 				    srp_cm_handler, target);
211 	if (IS_ERR(new_cm_id))
212 		return PTR_ERR(new_cm_id);
213 
214 	if (target->cm_id)
215 		ib_destroy_cm_id(target->cm_id);
216 	target->cm_id = new_cm_id;
217 
218 	return 0;
219 }
220 
221 static int srp_create_target_ib(struct srp_target_port *target)
222 {
223 	struct ib_qp_init_attr *init_attr;
224 	int ret;
225 
226 	init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
227 	if (!init_attr)
228 		return -ENOMEM;
229 
230 	target->cq = ib_create_cq(target->srp_host->srp_dev->dev,
231 				  srp_completion, NULL, target, SRP_CQ_SIZE, 0);
232 	if (IS_ERR(target->cq)) {
233 		ret = PTR_ERR(target->cq);
234 		goto out;
235 	}
236 
237 	ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
238 
239 	init_attr->event_handler       = srp_qp_event;
240 	init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
241 	init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
242 	init_attr->cap.max_recv_sge    = 1;
243 	init_attr->cap.max_send_sge    = 1;
244 	init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
245 	init_attr->qp_type             = IB_QPT_RC;
246 	init_attr->send_cq             = target->cq;
247 	init_attr->recv_cq             = target->cq;
248 
249 	target->qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
250 	if (IS_ERR(target->qp)) {
251 		ret = PTR_ERR(target->qp);
252 		ib_destroy_cq(target->cq);
253 		goto out;
254 	}
255 
256 	ret = srp_init_qp(target, target->qp);
257 	if (ret) {
258 		ib_destroy_qp(target->qp);
259 		ib_destroy_cq(target->cq);
260 		goto out;
261 	}
262 
263 out:
264 	kfree(init_attr);
265 	return ret;
266 }
267 
268 static void srp_free_target_ib(struct srp_target_port *target)
269 {
270 	int i;
271 
272 	ib_destroy_qp(target->qp);
273 	ib_destroy_cq(target->cq);
274 
275 	for (i = 0; i < SRP_RQ_SIZE; ++i)
276 		srp_free_iu(target->srp_host, target->rx_ring[i]);
277 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
278 		srp_free_iu(target->srp_host, target->tx_ring[i]);
279 }
280 
281 static void srp_path_rec_completion(int status,
282 				    struct ib_sa_path_rec *pathrec,
283 				    void *target_ptr)
284 {
285 	struct srp_target_port *target = target_ptr;
286 
287 	target->status = status;
288 	if (status)
289 		shost_printk(KERN_ERR, target->scsi_host,
290 			     PFX "Got failed path rec status %d\n", status);
291 	else
292 		target->path = *pathrec;
293 	complete(&target->done);
294 }
295 
296 static int srp_lookup_path(struct srp_target_port *target)
297 {
298 	target->path.numb_path = 1;
299 
300 	init_completion(&target->done);
301 
302 	target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
303 						   target->srp_host->srp_dev->dev,
304 						   target->srp_host->port,
305 						   &target->path,
306 						   IB_SA_PATH_REC_SERVICE_ID	|
307 						   IB_SA_PATH_REC_DGID		|
308 						   IB_SA_PATH_REC_SGID		|
309 						   IB_SA_PATH_REC_NUMB_PATH	|
310 						   IB_SA_PATH_REC_PKEY,
311 						   SRP_PATH_REC_TIMEOUT_MS,
312 						   GFP_KERNEL,
313 						   srp_path_rec_completion,
314 						   target, &target->path_query);
315 	if (target->path_query_id < 0)
316 		return target->path_query_id;
317 
318 	wait_for_completion(&target->done);
319 
320 	if (target->status < 0)
321 		shost_printk(KERN_WARNING, target->scsi_host,
322 			     PFX "Path record query failed\n");
323 
324 	return target->status;
325 }
326 
327 static int srp_send_req(struct srp_target_port *target)
328 {
329 	struct {
330 		struct ib_cm_req_param param;
331 		struct srp_login_req   priv;
332 	} *req = NULL;
333 	int status;
334 
335 	req = kzalloc(sizeof *req, GFP_KERNEL);
336 	if (!req)
337 		return -ENOMEM;
338 
339 	req->param.primary_path 	      = &target->path;
340 	req->param.alternate_path 	      = NULL;
341 	req->param.service_id 		      = target->service_id;
342 	req->param.qp_num 		      = target->qp->qp_num;
343 	req->param.qp_type 		      = target->qp->qp_type;
344 	req->param.private_data 	      = &req->priv;
345 	req->param.private_data_len 	      = sizeof req->priv;
346 	req->param.flow_control 	      = 1;
347 
348 	get_random_bytes(&req->param.starting_psn, 4);
349 	req->param.starting_psn 	     &= 0xffffff;
350 
351 	/*
352 	 * Pick some arbitrary defaults here; we could make these
353 	 * module parameters if anyone cared about setting them.
354 	 */
355 	req->param.responder_resources	      = 4;
356 	req->param.remote_cm_response_timeout = 20;
357 	req->param.local_cm_response_timeout  = 20;
358 	req->param.retry_count 		      = 7;
359 	req->param.rnr_retry_count 	      = 7;
360 	req->param.max_cm_retries 	      = 15;
361 
362 	req->priv.opcode     	= SRP_LOGIN_REQ;
363 	req->priv.tag        	= 0;
364 	req->priv.req_it_iu_len = cpu_to_be32(srp_max_iu_len);
365 	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
366 					      SRP_BUF_FORMAT_INDIRECT);
367 	/*
368 	 * In the published SRP specification (draft rev. 16a), the
369 	 * port identifier format is 8 bytes of ID extension followed
370 	 * by 8 bytes of GUID.  Older drafts put the two halves in the
371 	 * opposite order, so that the GUID comes first.
372 	 *
373 	 * Targets conforming to these obsolete drafts can be
374 	 * recognized by the I/O Class they report.
375 	 */
376 	if (target->io_class == SRP_REV10_IB_IO_CLASS) {
377 		memcpy(req->priv.initiator_port_id,
378 		       &target->path.sgid.global.interface_id, 8);
379 		memcpy(req->priv.initiator_port_id + 8,
380 		       &target->initiator_ext, 8);
381 		memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
382 		memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
383 	} else {
384 		memcpy(req->priv.initiator_port_id,
385 		       &target->initiator_ext, 8);
386 		memcpy(req->priv.initiator_port_id + 8,
387 		       &target->path.sgid.global.interface_id, 8);
388 		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
389 		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
390 	}
391 
392 	/*
393 	 * Topspin/Cisco SRP targets will reject our login unless we
394 	 * zero out the first 8 bytes of our initiator port ID and set
395 	 * the second 8 bytes to the local node GUID.
396 	 */
397 	if (srp_target_is_topspin(target)) {
398 		shost_printk(KERN_DEBUG, target->scsi_host,
399 			     PFX "Topspin/Cisco initiator port ID workaround "
400 			     "activated for target GUID %016llx\n",
401 			     (unsigned long long) be64_to_cpu(target->ioc_guid));
402 		memset(req->priv.initiator_port_id, 0, 8);
403 		memcpy(req->priv.initiator_port_id + 8,
404 		       &target->srp_host->srp_dev->dev->node_guid, 8);
405 	}
406 
407 	status = ib_send_cm_req(target->cm_id, &req->param);
408 
409 	kfree(req);
410 
411 	return status;
412 }
413 
414 static void srp_disconnect_target(struct srp_target_port *target)
415 {
416 	/* XXX should send SRP_I_LOGOUT request */
417 
418 	init_completion(&target->done);
419 	if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
420 		shost_printk(KERN_DEBUG, target->scsi_host,
421 			     PFX "Sending CM DREQ failed\n");
422 		return;
423 	}
424 	wait_for_completion(&target->done);
425 }
426 
427 static void srp_remove_work(struct work_struct *work)
428 {
429 	struct srp_target_port *target =
430 		container_of(work, struct srp_target_port, work);
431 
432 	spin_lock_irq(target->scsi_host->host_lock);
433 	if (target->state != SRP_TARGET_DEAD) {
434 		spin_unlock_irq(target->scsi_host->host_lock);
435 		return;
436 	}
437 	target->state = SRP_TARGET_REMOVED;
438 	spin_unlock_irq(target->scsi_host->host_lock);
439 
440 	spin_lock(&target->srp_host->target_lock);
441 	list_del(&target->list);
442 	spin_unlock(&target->srp_host->target_lock);
443 
444 	srp_remove_host(target->scsi_host);
445 	scsi_remove_host(target->scsi_host);
446 	ib_destroy_cm_id(target->cm_id);
447 	srp_free_target_ib(target);
448 	scsi_host_put(target->scsi_host);
449 }
450 
451 static int srp_connect_target(struct srp_target_port *target)
452 {
453 	int retries = 3;
454 	int ret;
455 
456 	ret = srp_lookup_path(target);
457 	if (ret)
458 		return ret;
459 
460 	while (1) {
461 		init_completion(&target->done);
462 		ret = srp_send_req(target);
463 		if (ret)
464 			return ret;
465 		wait_for_completion(&target->done);
466 
467 		/*
468 		 * The CM event handling code will set status to
469 		 * SRP_PORT_REDIRECT if we get a port redirect REJ
470 		 * back, or SRP_DLID_REDIRECT if we get a lid/qp
471 		 * redirect REJ back.
472 		 */
473 		switch (target->status) {
474 		case 0:
475 			return 0;
476 
477 		case SRP_PORT_REDIRECT:
478 			ret = srp_lookup_path(target);
479 			if (ret)
480 				return ret;
481 			break;
482 
483 		case SRP_DLID_REDIRECT:
484 			break;
485 
486 		case SRP_STALE_CONN:
487 			/* Our current CM id was stale, and is now in timewait.
488 			 * Try to reconnect with a new one.
489 			 */
490 			if (!retries-- || srp_new_cm_id(target)) {
491 				shost_printk(KERN_ERR, target->scsi_host, PFX
492 					     "giving up on stale connection\n");
493 				target->status = -ECONNRESET;
494 				return target->status;
495 			}
496 
497 			shost_printk(KERN_ERR, target->scsi_host, PFX
498 				     "retrying stale connection\n");
499 			break;
500 
501 		default:
502 			return target->status;
503 		}
504 	}
505 }
506 
507 static void srp_unmap_data(struct scsi_cmnd *scmnd,
508 			   struct srp_target_port *target,
509 			   struct srp_request *req)
510 {
511 	if (!scsi_sglist(scmnd) ||
512 	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
513 	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
514 		return;
515 
516 	if (req->fmr) {
517 		ib_fmr_pool_unmap(req->fmr);
518 		req->fmr = NULL;
519 	}
520 
521 	ib_dma_unmap_sg(target->srp_host->srp_dev->dev, scsi_sglist(scmnd),
522 			scsi_sg_count(scmnd), scmnd->sc_data_direction);
523 }
524 
525 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
526 {
527 	srp_unmap_data(req->scmnd, target, req);
528 	list_move_tail(&req->list, &target->free_reqs);
529 }
530 
531 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
532 {
533 	req->scmnd->result = DID_RESET << 16;
534 	req->scmnd->scsi_done(req->scmnd);
535 	srp_remove_req(target, req);
536 }
537 
538 static int srp_reconnect_target(struct srp_target_port *target)
539 {
540 	struct ib_qp_attr qp_attr;
541 	struct srp_request *req, *tmp;
542 	struct ib_wc wc;
543 	int ret;
544 
545 	spin_lock_irq(target->scsi_host->host_lock);
546 	if (target->state != SRP_TARGET_LIVE) {
547 		spin_unlock_irq(target->scsi_host->host_lock);
548 		return -EAGAIN;
549 	}
550 	target->state = SRP_TARGET_CONNECTING;
551 	spin_unlock_irq(target->scsi_host->host_lock);
552 
553 	srp_disconnect_target(target);
554 	/*
555 	 * Now get a new local CM ID so that we avoid confusing the
556 	 * target in case things are really fouled up.
557 	 */
558 	ret = srp_new_cm_id(target);
559 	if (ret)
560 		goto err;
561 
562 	qp_attr.qp_state = IB_QPS_RESET;
563 	ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
564 	if (ret)
565 		goto err;
566 
567 	ret = srp_init_qp(target, target->qp);
568 	if (ret)
569 		goto err;
570 
571 	while (ib_poll_cq(target->cq, 1, &wc) > 0)
572 		; /* nothing */
573 
574 	spin_lock_irq(target->scsi_host->host_lock);
575 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
576 		srp_reset_req(target, req);
577 	spin_unlock_irq(target->scsi_host->host_lock);
578 
579 	target->rx_head	 = 0;
580 	target->tx_head	 = 0;
581 	target->tx_tail  = 0;
582 
583 	target->qp_in_error = 0;
584 	ret = srp_connect_target(target);
585 	if (ret)
586 		goto err;
587 
588 	spin_lock_irq(target->scsi_host->host_lock);
589 	if (target->state == SRP_TARGET_CONNECTING) {
590 		ret = 0;
591 		target->state = SRP_TARGET_LIVE;
592 	} else
593 		ret = -EAGAIN;
594 	spin_unlock_irq(target->scsi_host->host_lock);
595 
596 	return ret;
597 
598 err:
599 	shost_printk(KERN_ERR, target->scsi_host,
600 		     PFX "reconnect failed (%d), removing target port.\n", ret);
601 
602 	/*
603 	 * We couldn't reconnect, so kill our target port off.
604 	 * However, we have to defer the real removal because we might
605 	 * be in the context of the SCSI error handler now, which
606 	 * would deadlock if we call scsi_remove_host().
607 	 */
608 	spin_lock_irq(target->scsi_host->host_lock);
609 	if (target->state == SRP_TARGET_CONNECTING) {
610 		target->state = SRP_TARGET_DEAD;
611 		INIT_WORK(&target->work, srp_remove_work);
612 		schedule_work(&target->work);
613 	}
614 	spin_unlock_irq(target->scsi_host->host_lock);
615 
616 	return ret;
617 }
618 
619 static int srp_map_fmr(struct srp_target_port *target, struct scatterlist *scat,
620 		       int sg_cnt, struct srp_request *req,
621 		       struct srp_direct_buf *buf)
622 {
623 	u64 io_addr = 0;
624 	u64 *dma_pages;
625 	u32 len;
626 	int page_cnt;
627 	int i, j;
628 	int ret;
629 	struct srp_device *dev = target->srp_host->srp_dev;
630 	struct ib_device *ibdev = dev->dev;
631 	struct scatterlist *sg;
632 
633 	if (!dev->fmr_pool)
634 		return -ENODEV;
635 
636 	if (srp_target_is_mellanox(target) &&
637 	    (ib_sg_dma_address(ibdev, &scat[0]) & ~dev->fmr_page_mask))
638 		return -EINVAL;
639 
640 	len = page_cnt = 0;
641 	scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
642 		unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
643 
644 		if (ib_sg_dma_address(ibdev, sg) & ~dev->fmr_page_mask) {
645 			if (i > 0)
646 				return -EINVAL;
647 			else
648 				++page_cnt;
649 		}
650 		if ((ib_sg_dma_address(ibdev, sg) + dma_len) &
651 		    ~dev->fmr_page_mask) {
652 			if (i < sg_cnt - 1)
653 				return -EINVAL;
654 			else
655 				++page_cnt;
656 		}
657 
658 		len += dma_len;
659 	}
660 
661 	page_cnt += len >> dev->fmr_page_shift;
662 	if (page_cnt > SRP_FMR_SIZE)
663 		return -ENOMEM;
664 
665 	dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
666 	if (!dma_pages)
667 		return -ENOMEM;
668 
669 	page_cnt = 0;
670 	scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
671 		unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
672 
673 		for (j = 0; j < dma_len; j += dev->fmr_page_size)
674 			dma_pages[page_cnt++] =
675 				(ib_sg_dma_address(ibdev, sg) &
676 				 dev->fmr_page_mask) + j;
677 	}
678 
679 	req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
680 					dma_pages, page_cnt, io_addr);
681 	if (IS_ERR(req->fmr)) {
682 		ret = PTR_ERR(req->fmr);
683 		req->fmr = NULL;
684 		goto out;
685 	}
686 
687 	buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, &scat[0]) &
688 			       ~dev->fmr_page_mask);
689 	buf->key = cpu_to_be32(req->fmr->fmr->rkey);
690 	buf->len = cpu_to_be32(len);
691 
692 	ret = 0;
693 
694 out:
695 	kfree(dma_pages);
696 
697 	return ret;
698 }
699 
700 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
701 			struct srp_request *req)
702 {
703 	struct scatterlist *scat;
704 	struct srp_cmd *cmd = req->cmd->buf;
705 	int len, nents, count;
706 	u8 fmt = SRP_DATA_DESC_DIRECT;
707 	struct srp_device *dev;
708 	struct ib_device *ibdev;
709 
710 	if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
711 		return sizeof (struct srp_cmd);
712 
713 	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
714 	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
715 		shost_printk(KERN_WARNING, target->scsi_host,
716 			     PFX "Unhandled data direction %d\n",
717 			     scmnd->sc_data_direction);
718 		return -EINVAL;
719 	}
720 
721 	nents = scsi_sg_count(scmnd);
722 	scat  = scsi_sglist(scmnd);
723 
724 	dev = target->srp_host->srp_dev;
725 	ibdev = dev->dev;
726 
727 	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
728 
729 	fmt = SRP_DATA_DESC_DIRECT;
730 	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
731 
732 	if (count == 1) {
733 		/*
734 		 * The midlayer only generated a single gather/scatter
735 		 * entry, or DMA mapping coalesced everything to a
736 		 * single entry.  So a direct descriptor along with
737 		 * the DMA MR suffices.
738 		 */
739 		struct srp_direct_buf *buf = (void *) cmd->add_data;
740 
741 		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
742 		buf->key = cpu_to_be32(dev->mr->rkey);
743 		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
744 	} else if (srp_map_fmr(target, scat, count, req,
745 			       (void *) cmd->add_data)) {
746 		/*
747 		 * FMR mapping failed, and the scatterlist has more
748 		 * than one entry.  Generate an indirect memory
749 		 * descriptor.
750 		 */
751 		struct srp_indirect_buf *buf = (void *) cmd->add_data;
752 		struct scatterlist *sg;
753 		u32 datalen = 0;
754 		int i;
755 
756 		fmt = SRP_DATA_DESC_INDIRECT;
757 		len = sizeof (struct srp_cmd) +
758 			sizeof (struct srp_indirect_buf) +
759 			count * sizeof (struct srp_direct_buf);
760 
761 		scsi_for_each_sg(scmnd, sg, count, i) {
762 			unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
763 
764 			buf->desc_list[i].va  =
765 				cpu_to_be64(ib_sg_dma_address(ibdev, sg));
766 			buf->desc_list[i].key =
767 				cpu_to_be32(dev->mr->rkey);
768 			buf->desc_list[i].len = cpu_to_be32(dma_len);
769 			datalen += dma_len;
770 		}
771 
772 		if (scmnd->sc_data_direction == DMA_TO_DEVICE)
773 			cmd->data_out_desc_cnt = count;
774 		else
775 			cmd->data_in_desc_cnt = count;
776 
777 		buf->table_desc.va  =
778 			cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
779 		buf->table_desc.key =
780 			cpu_to_be32(target->srp_host->srp_dev->mr->rkey);
781 		buf->table_desc.len =
782 			cpu_to_be32(count * sizeof (struct srp_direct_buf));
783 
784 		buf->len = cpu_to_be32(datalen);
785 	}
786 
787 	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
788 		cmd->buf_fmt = fmt << 4;
789 	else
790 		cmd->buf_fmt = fmt;
791 
792 	return len;
793 }
794 
795 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
796 {
797 	struct srp_request *req;
798 	struct scsi_cmnd *scmnd;
799 	unsigned long flags;
800 	s32 delta;
801 
802 	delta = (s32) be32_to_cpu(rsp->req_lim_delta);
803 
804 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
805 
806 	target->req_lim += delta;
807 
808 	req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
809 
810 	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
811 		if (be32_to_cpu(rsp->resp_data_len) < 4)
812 			req->tsk_status = -1;
813 		else
814 			req->tsk_status = rsp->data[3];
815 		complete(&req->done);
816 	} else {
817 		scmnd = req->scmnd;
818 		if (!scmnd)
819 			shost_printk(KERN_ERR, target->scsi_host,
820 				     "Null scmnd for RSP w/tag %016llx\n",
821 				     (unsigned long long) rsp->tag);
822 		scmnd->result = rsp->status;
823 
824 		if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
825 			memcpy(scmnd->sense_buffer, rsp->data +
826 			       be32_to_cpu(rsp->resp_data_len),
827 			       min_t(int, be32_to_cpu(rsp->sense_data_len),
828 				     SCSI_SENSE_BUFFERSIZE));
829 		}
830 
831 		if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
832 			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
833 		else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
834 			scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
835 
836 		if (!req->tsk_mgmt) {
837 			scmnd->host_scribble = (void *) -1L;
838 			scmnd->scsi_done(scmnd);
839 
840 			srp_remove_req(target, req);
841 		} else
842 			req->cmd_done = 1;
843 	}
844 
845 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
846 }
847 
848 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
849 {
850 	struct ib_device *dev;
851 	struct srp_iu *iu;
852 	u8 opcode;
853 
854 	iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
855 
856 	dev = target->srp_host->srp_dev->dev;
857 	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
858 				   DMA_FROM_DEVICE);
859 
860 	opcode = *(u8 *) iu->buf;
861 
862 	if (0) {
863 		int i;
864 
865 		shost_printk(KERN_ERR, target->scsi_host,
866 			     PFX "recv completion, opcode 0x%02x\n", opcode);
867 
868 		for (i = 0; i < wc->byte_len; ++i) {
869 			if (i % 8 == 0)
870 				printk(KERN_ERR "  [%02x] ", i);
871 			printk(" %02x", ((u8 *) iu->buf)[i]);
872 			if ((i + 1) % 8 == 0)
873 				printk("\n");
874 		}
875 
876 		if (wc->byte_len % 8)
877 			printk("\n");
878 	}
879 
880 	switch (opcode) {
881 	case SRP_RSP:
882 		srp_process_rsp(target, iu->buf);
883 		break;
884 
885 	case SRP_T_LOGOUT:
886 		/* XXX Handle target logout */
887 		shost_printk(KERN_WARNING, target->scsi_host,
888 			     PFX "Got target logout request\n");
889 		break;
890 
891 	default:
892 		shost_printk(KERN_WARNING, target->scsi_host,
893 			     PFX "Unhandled SRP opcode 0x%02x\n", opcode);
894 		break;
895 	}
896 
897 	ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
898 				      DMA_FROM_DEVICE);
899 }
900 
901 static void srp_completion(struct ib_cq *cq, void *target_ptr)
902 {
903 	struct srp_target_port *target = target_ptr;
904 	struct ib_wc wc;
905 
906 	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
907 	while (ib_poll_cq(cq, 1, &wc) > 0) {
908 		if (wc.status) {
909 			shost_printk(KERN_ERR, target->scsi_host,
910 				     PFX "failed %s status %d\n",
911 				     wc.wr_id & SRP_OP_RECV ? "receive" : "send",
912 				     wc.status);
913 			target->qp_in_error = 1;
914 			break;
915 		}
916 
917 		if (wc.wr_id & SRP_OP_RECV)
918 			srp_handle_recv(target, &wc);
919 		else
920 			++target->tx_tail;
921 	}
922 }
923 
924 static int __srp_post_recv(struct srp_target_port *target)
925 {
926 	struct srp_iu *iu;
927 	struct ib_sge list;
928 	struct ib_recv_wr wr, *bad_wr;
929 	unsigned int next;
930 	int ret;
931 
932 	next 	 = target->rx_head & (SRP_RQ_SIZE - 1);
933 	wr.wr_id = next | SRP_OP_RECV;
934 	iu 	 = target->rx_ring[next];
935 
936 	list.addr   = iu->dma;
937 	list.length = iu->size;
938 	list.lkey   = target->srp_host->srp_dev->mr->lkey;
939 
940 	wr.next     = NULL;
941 	wr.sg_list  = &list;
942 	wr.num_sge  = 1;
943 
944 	ret = ib_post_recv(target->qp, &wr, &bad_wr);
945 	if (!ret)
946 		++target->rx_head;
947 
948 	return ret;
949 }
950 
951 static int srp_post_recv(struct srp_target_port *target)
952 {
953 	unsigned long flags;
954 	int ret;
955 
956 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
957 	ret = __srp_post_recv(target);
958 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
959 
960 	return ret;
961 }
962 
963 /*
964  * Must be called with target->scsi_host->host_lock held to protect
965  * req_lim and tx_head.  Lock cannot be dropped between call here and
966  * call to __srp_post_send().
967  */
968 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
969 					enum srp_request_type req_type)
970 {
971 	s32 min = (req_type == SRP_REQ_TASK_MGMT) ? 1 : 2;
972 
973 	if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
974 		return NULL;
975 
976 	if (target->req_lim < min) {
977 		++target->zero_req_lim;
978 		return NULL;
979 	}
980 
981 	return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
982 }
983 
984 /*
985  * Must be called with target->scsi_host->host_lock held to protect
986  * req_lim and tx_head.
987  */
988 static int __srp_post_send(struct srp_target_port *target,
989 			   struct srp_iu *iu, int len)
990 {
991 	struct ib_sge list;
992 	struct ib_send_wr wr, *bad_wr;
993 	int ret = 0;
994 
995 	list.addr   = iu->dma;
996 	list.length = len;
997 	list.lkey   = target->srp_host->srp_dev->mr->lkey;
998 
999 	wr.next       = NULL;
1000 	wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
1001 	wr.sg_list    = &list;
1002 	wr.num_sge    = 1;
1003 	wr.opcode     = IB_WR_SEND;
1004 	wr.send_flags = IB_SEND_SIGNALED;
1005 
1006 	ret = ib_post_send(target->qp, &wr, &bad_wr);
1007 
1008 	if (!ret) {
1009 		++target->tx_head;
1010 		--target->req_lim;
1011 	}
1012 
1013 	return ret;
1014 }
1015 
1016 static int srp_queuecommand(struct scsi_cmnd *scmnd,
1017 			    void (*done)(struct scsi_cmnd *))
1018 {
1019 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1020 	struct srp_request *req;
1021 	struct srp_iu *iu;
1022 	struct srp_cmd *cmd;
1023 	struct ib_device *dev;
1024 	int len;
1025 
1026 	if (target->state == SRP_TARGET_CONNECTING)
1027 		goto err;
1028 
1029 	if (target->state == SRP_TARGET_DEAD ||
1030 	    target->state == SRP_TARGET_REMOVED) {
1031 		scmnd->result = DID_BAD_TARGET << 16;
1032 		done(scmnd);
1033 		return 0;
1034 	}
1035 
1036 	iu = __srp_get_tx_iu(target, SRP_REQ_NORMAL);
1037 	if (!iu)
1038 		goto err;
1039 
1040 	dev = target->srp_host->srp_dev->dev;
1041 	ib_dma_sync_single_for_cpu(dev, iu->dma, srp_max_iu_len,
1042 				   DMA_TO_DEVICE);
1043 
1044 	req = list_entry(target->free_reqs.next, struct srp_request, list);
1045 
1046 	scmnd->scsi_done     = done;
1047 	scmnd->result        = 0;
1048 	scmnd->host_scribble = (void *) (long) req->index;
1049 
1050 	cmd = iu->buf;
1051 	memset(cmd, 0, sizeof *cmd);
1052 
1053 	cmd->opcode = SRP_CMD;
1054 	cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1055 	cmd->tag    = req->index;
1056 	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1057 
1058 	req->scmnd    = scmnd;
1059 	req->cmd      = iu;
1060 	req->cmd_done = 0;
1061 	req->tsk_mgmt = NULL;
1062 
1063 	len = srp_map_data(scmnd, target, req);
1064 	if (len < 0) {
1065 		shost_printk(KERN_ERR, target->scsi_host,
1066 			     PFX "Failed to map data\n");
1067 		goto err;
1068 	}
1069 
1070 	if (__srp_post_recv(target)) {
1071 		shost_printk(KERN_ERR, target->scsi_host, PFX "Recv failed\n");
1072 		goto err_unmap;
1073 	}
1074 
1075 	ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
1076 				      DMA_TO_DEVICE);
1077 
1078 	if (__srp_post_send(target, iu, len)) {
1079 		shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1080 		goto err_unmap;
1081 	}
1082 
1083 	list_move_tail(&req->list, &target->req_queue);
1084 
1085 	return 0;
1086 
1087 err_unmap:
1088 	srp_unmap_data(scmnd, target, req);
1089 
1090 err:
1091 	return SCSI_MLQUEUE_HOST_BUSY;
1092 }
1093 
1094 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1095 {
1096 	int i;
1097 
1098 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1099 		target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1100 						  target->max_ti_iu_len,
1101 						  GFP_KERNEL, DMA_FROM_DEVICE);
1102 		if (!target->rx_ring[i])
1103 			goto err;
1104 	}
1105 
1106 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1107 		target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1108 						  srp_max_iu_len,
1109 						  GFP_KERNEL, DMA_TO_DEVICE);
1110 		if (!target->tx_ring[i])
1111 			goto err;
1112 	}
1113 
1114 	return 0;
1115 
1116 err:
1117 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1118 		srp_free_iu(target->srp_host, target->rx_ring[i]);
1119 		target->rx_ring[i] = NULL;
1120 	}
1121 
1122 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1123 		srp_free_iu(target->srp_host, target->tx_ring[i]);
1124 		target->tx_ring[i] = NULL;
1125 	}
1126 
1127 	return -ENOMEM;
1128 }
1129 
1130 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1131 			       struct ib_cm_event *event,
1132 			       struct srp_target_port *target)
1133 {
1134 	struct Scsi_Host *shost = target->scsi_host;
1135 	struct ib_class_port_info *cpi;
1136 	int opcode;
1137 
1138 	switch (event->param.rej_rcvd.reason) {
1139 	case IB_CM_REJ_PORT_CM_REDIRECT:
1140 		cpi = event->param.rej_rcvd.ari;
1141 		target->path.dlid = cpi->redirect_lid;
1142 		target->path.pkey = cpi->redirect_pkey;
1143 		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1144 		memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1145 
1146 		target->status = target->path.dlid ?
1147 			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1148 		break;
1149 
1150 	case IB_CM_REJ_PORT_REDIRECT:
1151 		if (srp_target_is_topspin(target)) {
1152 			/*
1153 			 * Topspin/Cisco SRP gateways incorrectly send
1154 			 * reject reason code 25 when they mean 24
1155 			 * (port redirect).
1156 			 */
1157 			memcpy(target->path.dgid.raw,
1158 			       event->param.rej_rcvd.ari, 16);
1159 
1160 			shost_printk(KERN_DEBUG, shost,
1161 				     PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1162 				     (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1163 				     (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1164 
1165 			target->status = SRP_PORT_REDIRECT;
1166 		} else {
1167 			shost_printk(KERN_WARNING, shost,
1168 				     "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1169 			target->status = -ECONNRESET;
1170 		}
1171 		break;
1172 
1173 	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1174 		shost_printk(KERN_WARNING, shost,
1175 			    "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1176 		target->status = -ECONNRESET;
1177 		break;
1178 
1179 	case IB_CM_REJ_CONSUMER_DEFINED:
1180 		opcode = *(u8 *) event->private_data;
1181 		if (opcode == SRP_LOGIN_REJ) {
1182 			struct srp_login_rej *rej = event->private_data;
1183 			u32 reason = be32_to_cpu(rej->reason);
1184 
1185 			if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1186 				shost_printk(KERN_WARNING, shost,
1187 					     PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1188 			else
1189 				shost_printk(KERN_WARNING, shost,
1190 					    PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1191 		} else
1192 			shost_printk(KERN_WARNING, shost,
1193 				     "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1194 				     " opcode 0x%02x\n", opcode);
1195 		target->status = -ECONNRESET;
1196 		break;
1197 
1198 	case IB_CM_REJ_STALE_CONN:
1199 		shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
1200 		target->status = SRP_STALE_CONN;
1201 		break;
1202 
1203 	default:
1204 		shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
1205 			     event->param.rej_rcvd.reason);
1206 		target->status = -ECONNRESET;
1207 	}
1208 }
1209 
1210 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1211 {
1212 	struct srp_target_port *target = cm_id->context;
1213 	struct ib_qp_attr *qp_attr = NULL;
1214 	int attr_mask = 0;
1215 	int comp = 0;
1216 	int opcode = 0;
1217 
1218 	switch (event->event) {
1219 	case IB_CM_REQ_ERROR:
1220 		shost_printk(KERN_DEBUG, target->scsi_host,
1221 			     PFX "Sending CM REQ failed\n");
1222 		comp = 1;
1223 		target->status = -ECONNRESET;
1224 		break;
1225 
1226 	case IB_CM_REP_RECEIVED:
1227 		comp = 1;
1228 		opcode = *(u8 *) event->private_data;
1229 
1230 		if (opcode == SRP_LOGIN_RSP) {
1231 			struct srp_login_rsp *rsp = event->private_data;
1232 
1233 			target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1234 			target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1235 
1236 			target->scsi_host->can_queue = min(target->req_lim,
1237 							   target->scsi_host->can_queue);
1238 		} else {
1239 			shost_printk(KERN_WARNING, target->scsi_host,
1240 				    PFX "Unhandled RSP opcode %#x\n", opcode);
1241 			target->status = -ECONNRESET;
1242 			break;
1243 		}
1244 
1245 		if (!target->rx_ring[0]) {
1246 			target->status = srp_alloc_iu_bufs(target);
1247 			if (target->status)
1248 				break;
1249 		}
1250 
1251 		qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1252 		if (!qp_attr) {
1253 			target->status = -ENOMEM;
1254 			break;
1255 		}
1256 
1257 		qp_attr->qp_state = IB_QPS_RTR;
1258 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1259 		if (target->status)
1260 			break;
1261 
1262 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1263 		if (target->status)
1264 			break;
1265 
1266 		target->status = srp_post_recv(target);
1267 		if (target->status)
1268 			break;
1269 
1270 		qp_attr->qp_state = IB_QPS_RTS;
1271 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1272 		if (target->status)
1273 			break;
1274 
1275 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1276 		if (target->status)
1277 			break;
1278 
1279 		target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1280 		if (target->status)
1281 			break;
1282 
1283 		break;
1284 
1285 	case IB_CM_REJ_RECEIVED:
1286 		shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
1287 		comp = 1;
1288 
1289 		srp_cm_rej_handler(cm_id, event, target);
1290 		break;
1291 
1292 	case IB_CM_DREQ_RECEIVED:
1293 		shost_printk(KERN_WARNING, target->scsi_host,
1294 			     PFX "DREQ received - connection closed\n");
1295 		if (ib_send_cm_drep(cm_id, NULL, 0))
1296 			shost_printk(KERN_ERR, target->scsi_host,
1297 				     PFX "Sending CM DREP failed\n");
1298 		break;
1299 
1300 	case IB_CM_TIMEWAIT_EXIT:
1301 		shost_printk(KERN_ERR, target->scsi_host,
1302 			     PFX "connection closed\n");
1303 
1304 		comp = 1;
1305 		target->status = 0;
1306 		break;
1307 
1308 	case IB_CM_MRA_RECEIVED:
1309 	case IB_CM_DREQ_ERROR:
1310 	case IB_CM_DREP_RECEIVED:
1311 		break;
1312 
1313 	default:
1314 		shost_printk(KERN_WARNING, target->scsi_host,
1315 			     PFX "Unhandled CM event %d\n", event->event);
1316 		break;
1317 	}
1318 
1319 	if (comp)
1320 		complete(&target->done);
1321 
1322 	kfree(qp_attr);
1323 
1324 	return 0;
1325 }
1326 
1327 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1328 			     struct srp_request *req, u8 func)
1329 {
1330 	struct srp_iu *iu;
1331 	struct srp_tsk_mgmt *tsk_mgmt;
1332 
1333 	spin_lock_irq(target->scsi_host->host_lock);
1334 
1335 	if (target->state == SRP_TARGET_DEAD ||
1336 	    target->state == SRP_TARGET_REMOVED) {
1337 		req->scmnd->result = DID_BAD_TARGET << 16;
1338 		goto out;
1339 	}
1340 
1341 	init_completion(&req->done);
1342 
1343 	iu = __srp_get_tx_iu(target, SRP_REQ_TASK_MGMT);
1344 	if (!iu)
1345 		goto out;
1346 
1347 	tsk_mgmt = iu->buf;
1348 	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1349 
1350 	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
1351 	tsk_mgmt->lun 		= cpu_to_be64((u64) req->scmnd->device->lun << 48);
1352 	tsk_mgmt->tag 		= req->index | SRP_TAG_TSK_MGMT;
1353 	tsk_mgmt->tsk_mgmt_func = func;
1354 	tsk_mgmt->task_tag 	= req->index;
1355 
1356 	if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1357 		goto out;
1358 
1359 	req->tsk_mgmt = iu;
1360 
1361 	spin_unlock_irq(target->scsi_host->host_lock);
1362 
1363 	if (!wait_for_completion_timeout(&req->done,
1364 					 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1365 		return -1;
1366 
1367 	return 0;
1368 
1369 out:
1370 	spin_unlock_irq(target->scsi_host->host_lock);
1371 	return -1;
1372 }
1373 
1374 static int srp_find_req(struct srp_target_port *target,
1375 			struct scsi_cmnd *scmnd,
1376 			struct srp_request **req)
1377 {
1378 	if (scmnd->host_scribble == (void *) -1L)
1379 		return -1;
1380 
1381 	*req = &target->req_ring[(long) scmnd->host_scribble];
1382 
1383 	return 0;
1384 }
1385 
1386 static int srp_abort(struct scsi_cmnd *scmnd)
1387 {
1388 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1389 	struct srp_request *req;
1390 	int ret = SUCCESS;
1391 
1392 	shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
1393 
1394 	if (target->qp_in_error)
1395 		return FAILED;
1396 	if (srp_find_req(target, scmnd, &req))
1397 		return FAILED;
1398 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
1399 		return FAILED;
1400 
1401 	spin_lock_irq(target->scsi_host->host_lock);
1402 
1403 	if (req->cmd_done) {
1404 		srp_remove_req(target, req);
1405 		scmnd->scsi_done(scmnd);
1406 	} else if (!req->tsk_status) {
1407 		srp_remove_req(target, req);
1408 		scmnd->result = DID_ABORT << 16;
1409 	} else
1410 		ret = FAILED;
1411 
1412 	spin_unlock_irq(target->scsi_host->host_lock);
1413 
1414 	return ret;
1415 }
1416 
1417 static int srp_reset_device(struct scsi_cmnd *scmnd)
1418 {
1419 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1420 	struct srp_request *req, *tmp;
1421 
1422 	shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
1423 
1424 	if (target->qp_in_error)
1425 		return FAILED;
1426 	if (srp_find_req(target, scmnd, &req))
1427 		return FAILED;
1428 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
1429 		return FAILED;
1430 	if (req->tsk_status)
1431 		return FAILED;
1432 
1433 	spin_lock_irq(target->scsi_host->host_lock);
1434 
1435 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
1436 		if (req->scmnd->device == scmnd->device)
1437 			srp_reset_req(target, req);
1438 
1439 	spin_unlock_irq(target->scsi_host->host_lock);
1440 
1441 	return SUCCESS;
1442 }
1443 
1444 static int srp_reset_host(struct scsi_cmnd *scmnd)
1445 {
1446 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1447 	int ret = FAILED;
1448 
1449 	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
1450 
1451 	if (!srp_reconnect_target(target))
1452 		ret = SUCCESS;
1453 
1454 	return ret;
1455 }
1456 
1457 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
1458 			   char *buf)
1459 {
1460 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1461 
1462 	if (target->state == SRP_TARGET_DEAD ||
1463 	    target->state == SRP_TARGET_REMOVED)
1464 		return -ENODEV;
1465 
1466 	return sprintf(buf, "0x%016llx\n",
1467 		       (unsigned long long) be64_to_cpu(target->id_ext));
1468 }
1469 
1470 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
1471 			     char *buf)
1472 {
1473 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1474 
1475 	if (target->state == SRP_TARGET_DEAD ||
1476 	    target->state == SRP_TARGET_REMOVED)
1477 		return -ENODEV;
1478 
1479 	return sprintf(buf, "0x%016llx\n",
1480 		       (unsigned long long) be64_to_cpu(target->ioc_guid));
1481 }
1482 
1483 static ssize_t show_service_id(struct device *dev,
1484 			       struct device_attribute *attr, char *buf)
1485 {
1486 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1487 
1488 	if (target->state == SRP_TARGET_DEAD ||
1489 	    target->state == SRP_TARGET_REMOVED)
1490 		return -ENODEV;
1491 
1492 	return sprintf(buf, "0x%016llx\n",
1493 		       (unsigned long long) be64_to_cpu(target->service_id));
1494 }
1495 
1496 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
1497 			 char *buf)
1498 {
1499 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1500 
1501 	if (target->state == SRP_TARGET_DEAD ||
1502 	    target->state == SRP_TARGET_REMOVED)
1503 		return -ENODEV;
1504 
1505 	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1506 }
1507 
1508 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
1509 			 char *buf)
1510 {
1511 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1512 
1513 	if (target->state == SRP_TARGET_DEAD ||
1514 	    target->state == SRP_TARGET_REMOVED)
1515 		return -ENODEV;
1516 
1517 	return sprintf(buf, "%pI6\n", target->path.dgid.raw);
1518 }
1519 
1520 static ssize_t show_orig_dgid(struct device *dev,
1521 			      struct device_attribute *attr, char *buf)
1522 {
1523 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1524 
1525 	if (target->state == SRP_TARGET_DEAD ||
1526 	    target->state == SRP_TARGET_REMOVED)
1527 		return -ENODEV;
1528 
1529 	return sprintf(buf, "%pI6\n", target->orig_dgid);
1530 }
1531 
1532 static ssize_t show_zero_req_lim(struct device *dev,
1533 				 struct device_attribute *attr, char *buf)
1534 {
1535 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1536 
1537 	if (target->state == SRP_TARGET_DEAD ||
1538 	    target->state == SRP_TARGET_REMOVED)
1539 		return -ENODEV;
1540 
1541 	return sprintf(buf, "%d\n", target->zero_req_lim);
1542 }
1543 
1544 static ssize_t show_local_ib_port(struct device *dev,
1545 				  struct device_attribute *attr, char *buf)
1546 {
1547 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1548 
1549 	return sprintf(buf, "%d\n", target->srp_host->port);
1550 }
1551 
1552 static ssize_t show_local_ib_device(struct device *dev,
1553 				    struct device_attribute *attr, char *buf)
1554 {
1555 	struct srp_target_port *target = host_to_target(class_to_shost(dev));
1556 
1557 	return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
1558 }
1559 
1560 static DEVICE_ATTR(id_ext,	    S_IRUGO, show_id_ext,	   NULL);
1561 static DEVICE_ATTR(ioc_guid,	    S_IRUGO, show_ioc_guid,	   NULL);
1562 static DEVICE_ATTR(service_id,	    S_IRUGO, show_service_id,	   NULL);
1563 static DEVICE_ATTR(pkey,	    S_IRUGO, show_pkey,		   NULL);
1564 static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
1565 static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
1566 static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,	   NULL);
1567 static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
1568 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1569 
1570 static struct device_attribute *srp_host_attrs[] = {
1571 	&dev_attr_id_ext,
1572 	&dev_attr_ioc_guid,
1573 	&dev_attr_service_id,
1574 	&dev_attr_pkey,
1575 	&dev_attr_dgid,
1576 	&dev_attr_orig_dgid,
1577 	&dev_attr_zero_req_lim,
1578 	&dev_attr_local_ib_port,
1579 	&dev_attr_local_ib_device,
1580 	NULL
1581 };
1582 
1583 static struct scsi_host_template srp_template = {
1584 	.module				= THIS_MODULE,
1585 	.name				= "InfiniBand SRP initiator",
1586 	.proc_name			= DRV_NAME,
1587 	.info				= srp_target_info,
1588 	.queuecommand			= srp_queuecommand,
1589 	.eh_abort_handler		= srp_abort,
1590 	.eh_device_reset_handler	= srp_reset_device,
1591 	.eh_host_reset_handler		= srp_reset_host,
1592 	.can_queue			= SRP_SQ_SIZE,
1593 	.this_id			= -1,
1594 	.cmd_per_lun			= SRP_SQ_SIZE,
1595 	.use_clustering			= ENABLE_CLUSTERING,
1596 	.shost_attrs			= srp_host_attrs
1597 };
1598 
1599 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1600 {
1601 	struct srp_rport_identifiers ids;
1602 	struct srp_rport *rport;
1603 
1604 	sprintf(target->target_name, "SRP.T10:%016llX",
1605 		 (unsigned long long) be64_to_cpu(target->id_ext));
1606 
1607 	if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
1608 		return -ENODEV;
1609 
1610 	memcpy(ids.port_id, &target->id_ext, 8);
1611 	memcpy(ids.port_id + 8, &target->ioc_guid, 8);
1612 	ids.roles = SRP_RPORT_ROLE_TARGET;
1613 	rport = srp_rport_add(target->scsi_host, &ids);
1614 	if (IS_ERR(rport)) {
1615 		scsi_remove_host(target->scsi_host);
1616 		return PTR_ERR(rport);
1617 	}
1618 
1619 	spin_lock(&host->target_lock);
1620 	list_add_tail(&target->list, &host->target_list);
1621 	spin_unlock(&host->target_lock);
1622 
1623 	target->state = SRP_TARGET_LIVE;
1624 
1625 	scsi_scan_target(&target->scsi_host->shost_gendev,
1626 			 0, target->scsi_id, SCAN_WILD_CARD, 0);
1627 
1628 	return 0;
1629 }
1630 
1631 static void srp_release_dev(struct device *dev)
1632 {
1633 	struct srp_host *host =
1634 		container_of(dev, struct srp_host, dev);
1635 
1636 	complete(&host->released);
1637 }
1638 
1639 static struct class srp_class = {
1640 	.name    = "infiniband_srp",
1641 	.dev_release = srp_release_dev
1642 };
1643 
1644 /*
1645  * Target ports are added by writing
1646  *
1647  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1648  *     pkey=<P_Key>,service_id=<service ID>
1649  *
1650  * to the add_target sysfs attribute.
1651  */
1652 enum {
1653 	SRP_OPT_ERR		= 0,
1654 	SRP_OPT_ID_EXT		= 1 << 0,
1655 	SRP_OPT_IOC_GUID	= 1 << 1,
1656 	SRP_OPT_DGID		= 1 << 2,
1657 	SRP_OPT_PKEY		= 1 << 3,
1658 	SRP_OPT_SERVICE_ID	= 1 << 4,
1659 	SRP_OPT_MAX_SECT	= 1 << 5,
1660 	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
1661 	SRP_OPT_IO_CLASS	= 1 << 7,
1662 	SRP_OPT_INITIATOR_EXT	= 1 << 8,
1663 	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
1664 				   SRP_OPT_IOC_GUID	|
1665 				   SRP_OPT_DGID		|
1666 				   SRP_OPT_PKEY		|
1667 				   SRP_OPT_SERVICE_ID),
1668 };
1669 
1670 static const match_table_t srp_opt_tokens = {
1671 	{ SRP_OPT_ID_EXT,		"id_ext=%s" 		},
1672 	{ SRP_OPT_IOC_GUID,		"ioc_guid=%s" 		},
1673 	{ SRP_OPT_DGID,			"dgid=%s" 		},
1674 	{ SRP_OPT_PKEY,			"pkey=%x" 		},
1675 	{ SRP_OPT_SERVICE_ID,		"service_id=%s"		},
1676 	{ SRP_OPT_MAX_SECT,		"max_sect=%d" 		},
1677 	{ SRP_OPT_MAX_CMD_PER_LUN,	"max_cmd_per_lun=%d" 	},
1678 	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
1679 	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
1680 	{ SRP_OPT_ERR,			NULL 			}
1681 };
1682 
1683 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1684 {
1685 	char *options, *sep_opt;
1686 	char *p;
1687 	char dgid[3];
1688 	substring_t args[MAX_OPT_ARGS];
1689 	int opt_mask = 0;
1690 	int token;
1691 	int ret = -EINVAL;
1692 	int i;
1693 
1694 	options = kstrdup(buf, GFP_KERNEL);
1695 	if (!options)
1696 		return -ENOMEM;
1697 
1698 	sep_opt = options;
1699 	while ((p = strsep(&sep_opt, ",")) != NULL) {
1700 		if (!*p)
1701 			continue;
1702 
1703 		token = match_token(p, srp_opt_tokens, args);
1704 		opt_mask |= token;
1705 
1706 		switch (token) {
1707 		case SRP_OPT_ID_EXT:
1708 			p = match_strdup(args);
1709 			if (!p) {
1710 				ret = -ENOMEM;
1711 				goto out;
1712 			}
1713 			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1714 			kfree(p);
1715 			break;
1716 
1717 		case SRP_OPT_IOC_GUID:
1718 			p = match_strdup(args);
1719 			if (!p) {
1720 				ret = -ENOMEM;
1721 				goto out;
1722 			}
1723 			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1724 			kfree(p);
1725 			break;
1726 
1727 		case SRP_OPT_DGID:
1728 			p = match_strdup(args);
1729 			if (!p) {
1730 				ret = -ENOMEM;
1731 				goto out;
1732 			}
1733 			if (strlen(p) != 32) {
1734 				printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1735 				kfree(p);
1736 				goto out;
1737 			}
1738 
1739 			for (i = 0; i < 16; ++i) {
1740 				strlcpy(dgid, p + i * 2, 3);
1741 				target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1742 			}
1743 			kfree(p);
1744 			memcpy(target->orig_dgid, target->path.dgid.raw, 16);
1745 			break;
1746 
1747 		case SRP_OPT_PKEY:
1748 			if (match_hex(args, &token)) {
1749 				printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1750 				goto out;
1751 			}
1752 			target->path.pkey = cpu_to_be16(token);
1753 			break;
1754 
1755 		case SRP_OPT_SERVICE_ID:
1756 			p = match_strdup(args);
1757 			if (!p) {
1758 				ret = -ENOMEM;
1759 				goto out;
1760 			}
1761 			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1762 			target->path.service_id = target->service_id;
1763 			kfree(p);
1764 			break;
1765 
1766 		case SRP_OPT_MAX_SECT:
1767 			if (match_int(args, &token)) {
1768 				printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1769 				goto out;
1770 			}
1771 			target->scsi_host->max_sectors = token;
1772 			break;
1773 
1774 		case SRP_OPT_MAX_CMD_PER_LUN:
1775 			if (match_int(args, &token)) {
1776 				printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
1777 				goto out;
1778 			}
1779 			target->scsi_host->cmd_per_lun = min(token, SRP_SQ_SIZE);
1780 			break;
1781 
1782 		case SRP_OPT_IO_CLASS:
1783 			if (match_hex(args, &token)) {
1784 				printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
1785 				goto out;
1786 			}
1787 			if (token != SRP_REV10_IB_IO_CLASS &&
1788 			    token != SRP_REV16A_IB_IO_CLASS) {
1789 				printk(KERN_WARNING PFX "unknown IO class parameter value"
1790 				       " %x specified (use %x or %x).\n",
1791 				       token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
1792 				goto out;
1793 			}
1794 			target->io_class = token;
1795 			break;
1796 
1797 		case SRP_OPT_INITIATOR_EXT:
1798 			p = match_strdup(args);
1799 			if (!p) {
1800 				ret = -ENOMEM;
1801 				goto out;
1802 			}
1803 			target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1804 			kfree(p);
1805 			break;
1806 
1807 		default:
1808 			printk(KERN_WARNING PFX "unknown parameter or missing value "
1809 			       "'%s' in target creation request\n", p);
1810 			goto out;
1811 		}
1812 	}
1813 
1814 	if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1815 		ret = 0;
1816 	else
1817 		for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1818 			if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1819 			    !(srp_opt_tokens[i].token & opt_mask))
1820 				printk(KERN_WARNING PFX "target creation request is "
1821 				       "missing parameter '%s'\n",
1822 				       srp_opt_tokens[i].pattern);
1823 
1824 out:
1825 	kfree(options);
1826 	return ret;
1827 }
1828 
1829 static ssize_t srp_create_target(struct device *dev,
1830 				 struct device_attribute *attr,
1831 				 const char *buf, size_t count)
1832 {
1833 	struct srp_host *host =
1834 		container_of(dev, struct srp_host, dev);
1835 	struct Scsi_Host *target_host;
1836 	struct srp_target_port *target;
1837 	int ret;
1838 	int i;
1839 
1840 	target_host = scsi_host_alloc(&srp_template,
1841 				      sizeof (struct srp_target_port));
1842 	if (!target_host)
1843 		return -ENOMEM;
1844 
1845 	target_host->transportt = ib_srp_transport_template;
1846 	target_host->max_lun     = SRP_MAX_LUN;
1847 	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
1848 
1849 	target = host_to_target(target_host);
1850 
1851 	target->io_class   = SRP_REV16A_IB_IO_CLASS;
1852 	target->scsi_host  = target_host;
1853 	target->srp_host   = host;
1854 
1855 	INIT_LIST_HEAD(&target->free_reqs);
1856 	INIT_LIST_HEAD(&target->req_queue);
1857 	for (i = 0; i < SRP_SQ_SIZE; ++i) {
1858 		target->req_ring[i].index = i;
1859 		list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1860 	}
1861 
1862 	ret = srp_parse_options(buf, target);
1863 	if (ret)
1864 		goto err;
1865 
1866 	ib_query_gid(host->srp_dev->dev, host->port, 0, &target->path.sgid);
1867 
1868 	shost_printk(KERN_DEBUG, target->scsi_host, PFX
1869 		     "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1870 		     "service_id %016llx dgid %pI6\n",
1871 	       (unsigned long long) be64_to_cpu(target->id_ext),
1872 	       (unsigned long long) be64_to_cpu(target->ioc_guid),
1873 	       be16_to_cpu(target->path.pkey),
1874 	       (unsigned long long) be64_to_cpu(target->service_id),
1875 	       target->path.dgid.raw);
1876 
1877 	ret = srp_create_target_ib(target);
1878 	if (ret)
1879 		goto err;
1880 
1881 	ret = srp_new_cm_id(target);
1882 	if (ret)
1883 		goto err_free;
1884 
1885 	target->qp_in_error = 0;
1886 	ret = srp_connect_target(target);
1887 	if (ret) {
1888 		shost_printk(KERN_ERR, target->scsi_host,
1889 			     PFX "Connection failed\n");
1890 		goto err_cm_id;
1891 	}
1892 
1893 	ret = srp_add_target(host, target);
1894 	if (ret)
1895 		goto err_disconnect;
1896 
1897 	return count;
1898 
1899 err_disconnect:
1900 	srp_disconnect_target(target);
1901 
1902 err_cm_id:
1903 	ib_destroy_cm_id(target->cm_id);
1904 
1905 err_free:
1906 	srp_free_target_ib(target);
1907 
1908 err:
1909 	scsi_host_put(target_host);
1910 
1911 	return ret;
1912 }
1913 
1914 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1915 
1916 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
1917 			  char *buf)
1918 {
1919 	struct srp_host *host = container_of(dev, struct srp_host, dev);
1920 
1921 	return sprintf(buf, "%s\n", host->srp_dev->dev->name);
1922 }
1923 
1924 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1925 
1926 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
1927 			 char *buf)
1928 {
1929 	struct srp_host *host = container_of(dev, struct srp_host, dev);
1930 
1931 	return sprintf(buf, "%d\n", host->port);
1932 }
1933 
1934 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1935 
1936 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
1937 {
1938 	struct srp_host *host;
1939 
1940 	host = kzalloc(sizeof *host, GFP_KERNEL);
1941 	if (!host)
1942 		return NULL;
1943 
1944 	INIT_LIST_HEAD(&host->target_list);
1945 	spin_lock_init(&host->target_lock);
1946 	init_completion(&host->released);
1947 	host->srp_dev = device;
1948 	host->port = port;
1949 
1950 	host->dev.class = &srp_class;
1951 	host->dev.parent = device->dev->dma_device;
1952 	dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
1953 
1954 	if (device_register(&host->dev))
1955 		goto free_host;
1956 	if (device_create_file(&host->dev, &dev_attr_add_target))
1957 		goto err_class;
1958 	if (device_create_file(&host->dev, &dev_attr_ibdev))
1959 		goto err_class;
1960 	if (device_create_file(&host->dev, &dev_attr_port))
1961 		goto err_class;
1962 
1963 	return host;
1964 
1965 err_class:
1966 	device_unregister(&host->dev);
1967 
1968 free_host:
1969 	kfree(host);
1970 
1971 	return NULL;
1972 }
1973 
1974 static void srp_add_one(struct ib_device *device)
1975 {
1976 	struct srp_device *srp_dev;
1977 	struct ib_device_attr *dev_attr;
1978 	struct ib_fmr_pool_param fmr_param;
1979 	struct srp_host *host;
1980 	int s, e, p;
1981 
1982 	dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
1983 	if (!dev_attr)
1984 		return;
1985 
1986 	if (ib_query_device(device, dev_attr)) {
1987 		printk(KERN_WARNING PFX "Query device failed for %s\n",
1988 		       device->name);
1989 		goto free_attr;
1990 	}
1991 
1992 	srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
1993 	if (!srp_dev)
1994 		goto free_attr;
1995 
1996 	/*
1997 	 * Use the smallest page size supported by the HCA, down to a
1998 	 * minimum of 512 bytes (which is the smallest sector that a
1999 	 * SCSI command will ever carry).
2000 	 */
2001 	srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
2002 	srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
2003 	srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);
2004 
2005 	INIT_LIST_HEAD(&srp_dev->dev_list);
2006 
2007 	srp_dev->dev = device;
2008 	srp_dev->pd  = ib_alloc_pd(device);
2009 	if (IS_ERR(srp_dev->pd))
2010 		goto free_dev;
2011 
2012 	srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
2013 				    IB_ACCESS_LOCAL_WRITE |
2014 				    IB_ACCESS_REMOTE_READ |
2015 				    IB_ACCESS_REMOTE_WRITE);
2016 	if (IS_ERR(srp_dev->mr))
2017 		goto err_pd;
2018 
2019 	memset(&fmr_param, 0, sizeof fmr_param);
2020 	fmr_param.pool_size	    = SRP_FMR_POOL_SIZE;
2021 	fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
2022 	fmr_param.cache		    = 1;
2023 	fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
2024 	fmr_param.page_shift	    = srp_dev->fmr_page_shift;
2025 	fmr_param.access	    = (IB_ACCESS_LOCAL_WRITE |
2026 				       IB_ACCESS_REMOTE_WRITE |
2027 				       IB_ACCESS_REMOTE_READ);
2028 
2029 	srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
2030 	if (IS_ERR(srp_dev->fmr_pool))
2031 		srp_dev->fmr_pool = NULL;
2032 
2033 	if (device->node_type == RDMA_NODE_IB_SWITCH) {
2034 		s = 0;
2035 		e = 0;
2036 	} else {
2037 		s = 1;
2038 		e = device->phys_port_cnt;
2039 	}
2040 
2041 	for (p = s; p <= e; ++p) {
2042 		host = srp_add_port(srp_dev, p);
2043 		if (host)
2044 			list_add_tail(&host->list, &srp_dev->dev_list);
2045 	}
2046 
2047 	ib_set_client_data(device, &srp_client, srp_dev);
2048 
2049 	goto free_attr;
2050 
2051 err_pd:
2052 	ib_dealloc_pd(srp_dev->pd);
2053 
2054 free_dev:
2055 	kfree(srp_dev);
2056 
2057 free_attr:
2058 	kfree(dev_attr);
2059 }
2060 
2061 static void srp_remove_one(struct ib_device *device)
2062 {
2063 	struct srp_device *srp_dev;
2064 	struct srp_host *host, *tmp_host;
2065 	LIST_HEAD(target_list);
2066 	struct srp_target_port *target, *tmp_target;
2067 
2068 	srp_dev = ib_get_client_data(device, &srp_client);
2069 
2070 	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2071 		device_unregister(&host->dev);
2072 		/*
2073 		 * Wait for the sysfs entry to go away, so that no new
2074 		 * target ports can be created.
2075 		 */
2076 		wait_for_completion(&host->released);
2077 
2078 		/*
2079 		 * Mark all target ports as removed, so we stop queueing
2080 		 * commands and don't try to reconnect.
2081 		 */
2082 		spin_lock(&host->target_lock);
2083 		list_for_each_entry(target, &host->target_list, list) {
2084 			spin_lock_irq(target->scsi_host->host_lock);
2085 			target->state = SRP_TARGET_REMOVED;
2086 			spin_unlock_irq(target->scsi_host->host_lock);
2087 		}
2088 		spin_unlock(&host->target_lock);
2089 
2090 		/*
2091 		 * Wait for any reconnection tasks that may have
2092 		 * started before we marked our target ports as
2093 		 * removed, and any target port removal tasks.
2094 		 */
2095 		flush_scheduled_work();
2096 
2097 		list_for_each_entry_safe(target, tmp_target,
2098 					 &host->target_list, list) {
2099 			srp_remove_host(target->scsi_host);
2100 			scsi_remove_host(target->scsi_host);
2101 			srp_disconnect_target(target);
2102 			ib_destroy_cm_id(target->cm_id);
2103 			srp_free_target_ib(target);
2104 			scsi_host_put(target->scsi_host);
2105 		}
2106 
2107 		kfree(host);
2108 	}
2109 
2110 	if (srp_dev->fmr_pool)
2111 		ib_destroy_fmr_pool(srp_dev->fmr_pool);
2112 	ib_dereg_mr(srp_dev->mr);
2113 	ib_dealloc_pd(srp_dev->pd);
2114 
2115 	kfree(srp_dev);
2116 }
2117 
2118 static struct srp_function_template ib_srp_transport_functions = {
2119 };
2120 
2121 static int __init srp_init_module(void)
2122 {
2123 	int ret;
2124 
2125 	if (srp_sg_tablesize > 255) {
2126 		printk(KERN_WARNING PFX "Clamping srp_sg_tablesize to 255\n");
2127 		srp_sg_tablesize = 255;
2128 	}
2129 
2130 	ib_srp_transport_template =
2131 		srp_attach_transport(&ib_srp_transport_functions);
2132 	if (!ib_srp_transport_template)
2133 		return -ENOMEM;
2134 
2135 	srp_template.sg_tablesize = srp_sg_tablesize;
2136 	srp_max_iu_len = (sizeof (struct srp_cmd) +
2137 			  sizeof (struct srp_indirect_buf) +
2138 			  srp_sg_tablesize * 16);
2139 
2140 	ret = class_register(&srp_class);
2141 	if (ret) {
2142 		printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
2143 		srp_release_transport(ib_srp_transport_template);
2144 		return ret;
2145 	}
2146 
2147 	ib_sa_register_client(&srp_sa_client);
2148 
2149 	ret = ib_register_client(&srp_client);
2150 	if (ret) {
2151 		printk(KERN_ERR PFX "couldn't register IB client\n");
2152 		srp_release_transport(ib_srp_transport_template);
2153 		ib_sa_unregister_client(&srp_sa_client);
2154 		class_unregister(&srp_class);
2155 		return ret;
2156 	}
2157 
2158 	return 0;
2159 }
2160 
2161 static void __exit srp_cleanup_module(void)
2162 {
2163 	ib_unregister_client(&srp_client);
2164 	ib_sa_unregister_client(&srp_sa_client);
2165 	class_unregister(&srp_class);
2166 	srp_release_transport(ib_srp_transport_template);
2167 }
2168 
2169 module_init(srp_init_module);
2170 module_exit(srp_cleanup_module);
2171