xref: /linux/drivers/infiniband/ulp/srp/ib_srp.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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  * $Id: ib_srp.c 3932 2005-11-01 17:19:29Z roland $
33  */
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 
44 #include <asm/atomic.h>
45 
46 #include <scsi/scsi.h>
47 #include <scsi/scsi_device.h>
48 #include <scsi/scsi_dbg.h>
49 #include <scsi/srp.h>
50 
51 #include <rdma/ib_cache.h>
52 
53 #include "ib_srp.h"
54 
55 #define DRV_NAME	"ib_srp"
56 #define PFX		DRV_NAME ": "
57 #define DRV_VERSION	"0.2"
58 #define DRV_RELDATE	"November 1, 2005"
59 
60 MODULE_AUTHOR("Roland Dreier");
61 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
62 		   "v" DRV_VERSION " (" DRV_RELDATE ")");
63 MODULE_LICENSE("Dual BSD/GPL");
64 
65 static int srp_sg_tablesize = SRP_DEF_SG_TABLESIZE;
66 static int srp_max_iu_len;
67 
68 module_param(srp_sg_tablesize, int, 0444);
69 MODULE_PARM_DESC(srp_sg_tablesize,
70 		 "Max number of gather/scatter entries per I/O (default is 12)");
71 
72 static int topspin_workarounds = 1;
73 
74 module_param(topspin_workarounds, int, 0444);
75 MODULE_PARM_DESC(topspin_workarounds,
76 		 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
77 
78 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
79 
80 static void srp_add_one(struct ib_device *device);
81 static void srp_remove_one(struct ib_device *device);
82 static void srp_completion(struct ib_cq *cq, void *target_ptr);
83 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
84 
85 static struct ib_client srp_client = {
86 	.name   = "srp",
87 	.add    = srp_add_one,
88 	.remove = srp_remove_one
89 };
90 
91 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
92 {
93 	return (struct srp_target_port *) host->hostdata;
94 }
95 
96 static const char *srp_target_info(struct Scsi_Host *host)
97 {
98 	return host_to_target(host)->target_name;
99 }
100 
101 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
102 				   gfp_t gfp_mask,
103 				   enum dma_data_direction direction)
104 {
105 	struct srp_iu *iu;
106 
107 	iu = kmalloc(sizeof *iu, gfp_mask);
108 	if (!iu)
109 		goto out;
110 
111 	iu->buf = kzalloc(size, gfp_mask);
112 	if (!iu->buf)
113 		goto out_free_iu;
114 
115 	iu->dma = dma_map_single(host->dev->dev->dma_device,
116 				 iu->buf, size, direction);
117 	if (dma_mapping_error(iu->dma))
118 		goto out_free_buf;
119 
120 	iu->size      = size;
121 	iu->direction = direction;
122 
123 	return iu;
124 
125 out_free_buf:
126 	kfree(iu->buf);
127 out_free_iu:
128 	kfree(iu);
129 out:
130 	return NULL;
131 }
132 
133 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
134 {
135 	if (!iu)
136 		return;
137 
138 	dma_unmap_single(host->dev->dev->dma_device,
139 			 iu->dma, iu->size, iu->direction);
140 	kfree(iu->buf);
141 	kfree(iu);
142 }
143 
144 static void srp_qp_event(struct ib_event *event, void *context)
145 {
146 	printk(KERN_ERR PFX "QP event %d\n", event->event);
147 }
148 
149 static int srp_init_qp(struct srp_target_port *target,
150 		       struct ib_qp *qp)
151 {
152 	struct ib_qp_attr *attr;
153 	int ret;
154 
155 	attr = kmalloc(sizeof *attr, GFP_KERNEL);
156 	if (!attr)
157 		return -ENOMEM;
158 
159 	ret = ib_find_cached_pkey(target->srp_host->dev->dev,
160 				  target->srp_host->port,
161 				  be16_to_cpu(target->path.pkey),
162 				  &attr->pkey_index);
163 	if (ret)
164 		goto out;
165 
166 	attr->qp_state        = IB_QPS_INIT;
167 	attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
168 				    IB_ACCESS_REMOTE_WRITE);
169 	attr->port_num        = target->srp_host->port;
170 
171 	ret = ib_modify_qp(qp, attr,
172 			   IB_QP_STATE		|
173 			   IB_QP_PKEY_INDEX	|
174 			   IB_QP_ACCESS_FLAGS	|
175 			   IB_QP_PORT);
176 
177 out:
178 	kfree(attr);
179 	return ret;
180 }
181 
182 static int srp_create_target_ib(struct srp_target_port *target)
183 {
184 	struct ib_qp_init_attr *init_attr;
185 	int ret;
186 
187 	init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
188 	if (!init_attr)
189 		return -ENOMEM;
190 
191 	target->cq = ib_create_cq(target->srp_host->dev->dev, srp_completion,
192 				  NULL, target, SRP_CQ_SIZE);
193 	if (IS_ERR(target->cq)) {
194 		ret = PTR_ERR(target->cq);
195 		goto out;
196 	}
197 
198 	ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
199 
200 	init_attr->event_handler       = srp_qp_event;
201 	init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
202 	init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
203 	init_attr->cap.max_recv_sge    = 1;
204 	init_attr->cap.max_send_sge    = 1;
205 	init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
206 	init_attr->qp_type             = IB_QPT_RC;
207 	init_attr->send_cq             = target->cq;
208 	init_attr->recv_cq             = target->cq;
209 
210 	target->qp = ib_create_qp(target->srp_host->dev->pd, init_attr);
211 	if (IS_ERR(target->qp)) {
212 		ret = PTR_ERR(target->qp);
213 		ib_destroy_cq(target->cq);
214 		goto out;
215 	}
216 
217 	ret = srp_init_qp(target, target->qp);
218 	if (ret) {
219 		ib_destroy_qp(target->qp);
220 		ib_destroy_cq(target->cq);
221 		goto out;
222 	}
223 
224 out:
225 	kfree(init_attr);
226 	return ret;
227 }
228 
229 static void srp_free_target_ib(struct srp_target_port *target)
230 {
231 	int i;
232 
233 	ib_destroy_qp(target->qp);
234 	ib_destroy_cq(target->cq);
235 
236 	for (i = 0; i < SRP_RQ_SIZE; ++i)
237 		srp_free_iu(target->srp_host, target->rx_ring[i]);
238 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
239 		srp_free_iu(target->srp_host, target->tx_ring[i]);
240 }
241 
242 static void srp_path_rec_completion(int status,
243 				    struct ib_sa_path_rec *pathrec,
244 				    void *target_ptr)
245 {
246 	struct srp_target_port *target = target_ptr;
247 
248 	target->status = status;
249 	if (status)
250 		printk(KERN_ERR PFX "Got failed path rec status %d\n", status);
251 	else
252 		target->path = *pathrec;
253 	complete(&target->done);
254 }
255 
256 static int srp_lookup_path(struct srp_target_port *target)
257 {
258 	target->path.numb_path = 1;
259 
260 	init_completion(&target->done);
261 
262 	target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev->dev,
263 						   target->srp_host->port,
264 						   &target->path,
265 						   IB_SA_PATH_REC_DGID		|
266 						   IB_SA_PATH_REC_SGID		|
267 						   IB_SA_PATH_REC_NUMB_PATH	|
268 						   IB_SA_PATH_REC_PKEY,
269 						   SRP_PATH_REC_TIMEOUT_MS,
270 						   GFP_KERNEL,
271 						   srp_path_rec_completion,
272 						   target, &target->path_query);
273 	if (target->path_query_id < 0)
274 		return target->path_query_id;
275 
276 	wait_for_completion(&target->done);
277 
278 	if (target->status < 0)
279 		printk(KERN_WARNING PFX "Path record query failed\n");
280 
281 	return target->status;
282 }
283 
284 static int srp_send_req(struct srp_target_port *target)
285 {
286 	struct {
287 		struct ib_cm_req_param param;
288 		struct srp_login_req   priv;
289 	} *req = NULL;
290 	int status;
291 
292 	req = kzalloc(sizeof *req, GFP_KERNEL);
293 	if (!req)
294 		return -ENOMEM;
295 
296 	req->param.primary_path 	      = &target->path;
297 	req->param.alternate_path 	      = NULL;
298 	req->param.service_id 		      = target->service_id;
299 	req->param.qp_num 		      = target->qp->qp_num;
300 	req->param.qp_type 		      = target->qp->qp_type;
301 	req->param.private_data 	      = &req->priv;
302 	req->param.private_data_len 	      = sizeof req->priv;
303 	req->param.flow_control 	      = 1;
304 
305 	get_random_bytes(&req->param.starting_psn, 4);
306 	req->param.starting_psn 	     &= 0xffffff;
307 
308 	/*
309 	 * Pick some arbitrary defaults here; we could make these
310 	 * module parameters if anyone cared about setting them.
311 	 */
312 	req->param.responder_resources	      = 4;
313 	req->param.remote_cm_response_timeout = 20;
314 	req->param.local_cm_response_timeout  = 20;
315 	req->param.retry_count 		      = 7;
316 	req->param.rnr_retry_count 	      = 7;
317 	req->param.max_cm_retries 	      = 15;
318 
319 	req->priv.opcode     	= SRP_LOGIN_REQ;
320 	req->priv.tag        	= 0;
321 	req->priv.req_it_iu_len = cpu_to_be32(srp_max_iu_len);
322 	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
323 					      SRP_BUF_FORMAT_INDIRECT);
324 	/*
325 	 * In the published SRP specification (draft rev. 16a), the
326 	 * port identifier format is 8 bytes of ID extension followed
327 	 * by 8 bytes of GUID.  Older drafts put the two halves in the
328 	 * opposite order, so that the GUID comes first.
329 	 *
330 	 * Targets conforming to these obsolete drafts can be
331 	 * recognized by the I/O Class they report.
332 	 */
333 	if (target->io_class == SRP_REV10_IB_IO_CLASS) {
334 		memcpy(req->priv.initiator_port_id,
335 		       target->srp_host->initiator_port_id + 8, 8);
336 		memcpy(req->priv.initiator_port_id + 8,
337 		       target->srp_host->initiator_port_id, 8);
338 		memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
339 		memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
340 	} else {
341 		memcpy(req->priv.initiator_port_id,
342 		       target->srp_host->initiator_port_id, 16);
343 		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
344 		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
345 	}
346 
347 	/*
348 	 * Topspin/Cisco SRP targets will reject our login unless we
349 	 * zero out the first 8 bytes of our initiator port ID.  The
350 	 * second 8 bytes must be our local node GUID, but we always
351 	 * use that anyway.
352 	 */
353 	if (topspin_workarounds && !memcmp(&target->ioc_guid, topspin_oui, 3)) {
354 		printk(KERN_DEBUG PFX "Topspin/Cisco initiator port ID workaround "
355 		       "activated for target GUID %016llx\n",
356 		       (unsigned long long) be64_to_cpu(target->ioc_guid));
357 		memset(req->priv.initiator_port_id, 0, 8);
358 	}
359 
360 	status = ib_send_cm_req(target->cm_id, &req->param);
361 
362 	kfree(req);
363 
364 	return status;
365 }
366 
367 static void srp_disconnect_target(struct srp_target_port *target)
368 {
369 	/* XXX should send SRP_I_LOGOUT request */
370 
371 	init_completion(&target->done);
372 	if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
373 		printk(KERN_DEBUG PFX "Sending CM DREQ failed\n");
374 		return;
375 	}
376 	wait_for_completion(&target->done);
377 }
378 
379 static void srp_remove_work(void *target_ptr)
380 {
381 	struct srp_target_port *target = target_ptr;
382 
383 	spin_lock_irq(target->scsi_host->host_lock);
384 	if (target->state != SRP_TARGET_DEAD) {
385 		spin_unlock_irq(target->scsi_host->host_lock);
386 		return;
387 	}
388 	target->state = SRP_TARGET_REMOVED;
389 	spin_unlock_irq(target->scsi_host->host_lock);
390 
391 	spin_lock(&target->srp_host->target_lock);
392 	list_del(&target->list);
393 	spin_unlock(&target->srp_host->target_lock);
394 
395 	scsi_remove_host(target->scsi_host);
396 	ib_destroy_cm_id(target->cm_id);
397 	srp_free_target_ib(target);
398 	scsi_host_put(target->scsi_host);
399 }
400 
401 static int srp_connect_target(struct srp_target_port *target)
402 {
403 	int ret;
404 
405 	ret = srp_lookup_path(target);
406 	if (ret)
407 		return ret;
408 
409 	while (1) {
410 		init_completion(&target->done);
411 		ret = srp_send_req(target);
412 		if (ret)
413 			return ret;
414 		wait_for_completion(&target->done);
415 
416 		/*
417 		 * The CM event handling code will set status to
418 		 * SRP_PORT_REDIRECT if we get a port redirect REJ
419 		 * back, or SRP_DLID_REDIRECT if we get a lid/qp
420 		 * redirect REJ back.
421 		 */
422 		switch (target->status) {
423 		case 0:
424 			return 0;
425 
426 		case SRP_PORT_REDIRECT:
427 			ret = srp_lookup_path(target);
428 			if (ret)
429 				return ret;
430 			break;
431 
432 		case SRP_DLID_REDIRECT:
433 			break;
434 
435 		default:
436 			return target->status;
437 		}
438 	}
439 }
440 
441 static void srp_unmap_data(struct scsi_cmnd *scmnd,
442 			   struct srp_target_port *target,
443 			   struct srp_request *req)
444 {
445 	struct scatterlist *scat;
446 	int nents;
447 
448 	if (!scmnd->request_buffer ||
449 	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
450 	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
451 		return;
452 
453 	if (req->fmr) {
454 		ib_fmr_pool_unmap(req->fmr);
455 		req->fmr = NULL;
456 	}
457 
458 	/*
459 	 * This handling of non-SG commands can be killed when the
460 	 * SCSI midlayer no longer generates non-SG commands.
461 	 */
462 	if (likely(scmnd->use_sg)) {
463 		nents = scmnd->use_sg;
464 		scat  = scmnd->request_buffer;
465 	} else {
466 		nents = 1;
467 		scat  = &req->fake_sg;
468 	}
469 
470 	dma_unmap_sg(target->srp_host->dev->dev->dma_device, scat, nents,
471 		     scmnd->sc_data_direction);
472 }
473 
474 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
475 {
476 	srp_unmap_data(req->scmnd, target, req);
477 	list_move_tail(&req->list, &target->free_reqs);
478 }
479 
480 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
481 {
482 	req->scmnd->result = DID_RESET << 16;
483 	req->scmnd->scsi_done(req->scmnd);
484 	srp_remove_req(target, req);
485 }
486 
487 static int srp_reconnect_target(struct srp_target_port *target)
488 {
489 	struct ib_cm_id *new_cm_id;
490 	struct ib_qp_attr qp_attr;
491 	struct srp_request *req, *tmp;
492 	struct ib_wc wc;
493 	int ret;
494 
495 	spin_lock_irq(target->scsi_host->host_lock);
496 	if (target->state != SRP_TARGET_LIVE) {
497 		spin_unlock_irq(target->scsi_host->host_lock);
498 		return -EAGAIN;
499 	}
500 	target->state = SRP_TARGET_CONNECTING;
501 	spin_unlock_irq(target->scsi_host->host_lock);
502 
503 	srp_disconnect_target(target);
504 	/*
505 	 * Now get a new local CM ID so that we avoid confusing the
506 	 * target in case things are really fouled up.
507 	 */
508 	new_cm_id = ib_create_cm_id(target->srp_host->dev->dev,
509 				    srp_cm_handler, target);
510 	if (IS_ERR(new_cm_id)) {
511 		ret = PTR_ERR(new_cm_id);
512 		goto err;
513 	}
514 	ib_destroy_cm_id(target->cm_id);
515 	target->cm_id = new_cm_id;
516 
517 	qp_attr.qp_state = IB_QPS_RESET;
518 	ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
519 	if (ret)
520 		goto err;
521 
522 	ret = srp_init_qp(target, target->qp);
523 	if (ret)
524 		goto err;
525 
526 	while (ib_poll_cq(target->cq, 1, &wc) > 0)
527 		; /* nothing */
528 
529 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
530 		srp_reset_req(target, req);
531 
532 	target->rx_head	 = 0;
533 	target->tx_head	 = 0;
534 	target->tx_tail  = 0;
535 
536 	ret = srp_connect_target(target);
537 	if (ret)
538 		goto err;
539 
540 	spin_lock_irq(target->scsi_host->host_lock);
541 	if (target->state == SRP_TARGET_CONNECTING) {
542 		ret = 0;
543 		target->state = SRP_TARGET_LIVE;
544 	} else
545 		ret = -EAGAIN;
546 	spin_unlock_irq(target->scsi_host->host_lock);
547 
548 	return ret;
549 
550 err:
551 	printk(KERN_ERR PFX "reconnect failed (%d), removing target port.\n", ret);
552 
553 	/*
554 	 * We couldn't reconnect, so kill our target port off.
555 	 * However, we have to defer the real removal because we might
556 	 * be in the context of the SCSI error handler now, which
557 	 * would deadlock if we call scsi_remove_host().
558 	 */
559 	spin_lock_irq(target->scsi_host->host_lock);
560 	if (target->state == SRP_TARGET_CONNECTING) {
561 		target->state = SRP_TARGET_DEAD;
562 		INIT_WORK(&target->work, srp_remove_work, target);
563 		schedule_work(&target->work);
564 	}
565 	spin_unlock_irq(target->scsi_host->host_lock);
566 
567 	return ret;
568 }
569 
570 static int srp_map_fmr(struct srp_device *dev, struct scatterlist *scat,
571 		       int sg_cnt, struct srp_request *req,
572 		       struct srp_direct_buf *buf)
573 {
574 	u64 io_addr = 0;
575 	u64 *dma_pages;
576 	u32 len;
577 	int page_cnt;
578 	int i, j;
579 	int ret;
580 
581 	if (!dev->fmr_pool)
582 		return -ENODEV;
583 
584 	len = page_cnt = 0;
585 	for (i = 0; i < sg_cnt; ++i) {
586 		if (sg_dma_address(&scat[i]) & ~dev->fmr_page_mask) {
587 			if (i > 0)
588 				return -EINVAL;
589 			else
590 				++page_cnt;
591 		}
592 		if ((sg_dma_address(&scat[i]) + sg_dma_len(&scat[i])) &
593 		    ~dev->fmr_page_mask) {
594 			if (i < sg_cnt - 1)
595 				return -EINVAL;
596 			else
597 				++page_cnt;
598 		}
599 
600 		len += sg_dma_len(&scat[i]);
601 	}
602 
603 	page_cnt += len >> dev->fmr_page_shift;
604 	if (page_cnt > SRP_FMR_SIZE)
605 		return -ENOMEM;
606 
607 	dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
608 	if (!dma_pages)
609 		return -ENOMEM;
610 
611 	page_cnt = 0;
612 	for (i = 0; i < sg_cnt; ++i)
613 		for (j = 0; j < sg_dma_len(&scat[i]); j += dev->fmr_page_size)
614 			dma_pages[page_cnt++] =
615 				(sg_dma_address(&scat[i]) & dev->fmr_page_mask) + j;
616 
617 	req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
618 					dma_pages, page_cnt, &io_addr);
619 	if (IS_ERR(req->fmr)) {
620 		ret = PTR_ERR(req->fmr);
621 		goto out;
622 	}
623 
624 	buf->va  = cpu_to_be64(sg_dma_address(&scat[0]) & ~dev->fmr_page_mask);
625 	buf->key = cpu_to_be32(req->fmr->fmr->rkey);
626 	buf->len = cpu_to_be32(len);
627 
628 	ret = 0;
629 
630 out:
631 	kfree(dma_pages);
632 
633 	return ret;
634 }
635 
636 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
637 			struct srp_request *req)
638 {
639 	struct scatterlist *scat;
640 	struct srp_cmd *cmd = req->cmd->buf;
641 	int len, nents, count;
642 	u8 fmt = SRP_DATA_DESC_DIRECT;
643 
644 	if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
645 		return sizeof (struct srp_cmd);
646 
647 	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
648 	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
649 		printk(KERN_WARNING PFX "Unhandled data direction %d\n",
650 		       scmnd->sc_data_direction);
651 		return -EINVAL;
652 	}
653 
654 	/*
655 	 * This handling of non-SG commands can be killed when the
656 	 * SCSI midlayer no longer generates non-SG commands.
657 	 */
658 	if (likely(scmnd->use_sg)) {
659 		nents = scmnd->use_sg;
660 		scat  = scmnd->request_buffer;
661 	} else {
662 		nents = 1;
663 		scat  = &req->fake_sg;
664 		sg_init_one(scat, scmnd->request_buffer, scmnd->request_bufflen);
665 	}
666 
667 	count = dma_map_sg(target->srp_host->dev->dev->dma_device,
668 			   scat, nents, scmnd->sc_data_direction);
669 
670 	fmt = SRP_DATA_DESC_DIRECT;
671 	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
672 
673 	if (count == 1) {
674 		/*
675 		 * The midlayer only generated a single gather/scatter
676 		 * entry, or DMA mapping coalesced everything to a
677 		 * single entry.  So a direct descriptor along with
678 		 * the DMA MR suffices.
679 		 */
680 		struct srp_direct_buf *buf = (void *) cmd->add_data;
681 
682 		buf->va  = cpu_to_be64(sg_dma_address(scat));
683 		buf->key = cpu_to_be32(target->srp_host->dev->mr->rkey);
684 		buf->len = cpu_to_be32(sg_dma_len(scat));
685 	} else if (srp_map_fmr(target->srp_host->dev, scat, count, req,
686 			       (void *) cmd->add_data)) {
687 		/*
688 		 * FMR mapping failed, and the scatterlist has more
689 		 * than one entry.  Generate an indirect memory
690 		 * descriptor.
691 		 */
692 		struct srp_indirect_buf *buf = (void *) cmd->add_data;
693 		u32 datalen = 0;
694 		int i;
695 
696 		fmt = SRP_DATA_DESC_INDIRECT;
697 		len = sizeof (struct srp_cmd) +
698 			sizeof (struct srp_indirect_buf) +
699 			count * sizeof (struct srp_direct_buf);
700 
701 		for (i = 0; i < count; ++i) {
702 			buf->desc_list[i].va  =
703 				cpu_to_be64(sg_dma_address(&scat[i]));
704 			buf->desc_list[i].key =
705 				cpu_to_be32(target->srp_host->dev->mr->rkey);
706 			buf->desc_list[i].len =
707 				cpu_to_be32(sg_dma_len(&scat[i]));
708 			datalen += sg_dma_len(&scat[i]);
709 		}
710 
711 		if (scmnd->sc_data_direction == DMA_TO_DEVICE)
712 			cmd->data_out_desc_cnt = count;
713 		else
714 			cmd->data_in_desc_cnt = count;
715 
716 		buf->table_desc.va  =
717 			cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
718 		buf->table_desc.key =
719 			cpu_to_be32(target->srp_host->dev->mr->rkey);
720 		buf->table_desc.len =
721 			cpu_to_be32(count * sizeof (struct srp_direct_buf));
722 
723 		buf->len = cpu_to_be32(datalen);
724 	}
725 
726 	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
727 		cmd->buf_fmt = fmt << 4;
728 	else
729 		cmd->buf_fmt = fmt;
730 
731 	return len;
732 }
733 
734 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
735 {
736 	struct srp_request *req;
737 	struct scsi_cmnd *scmnd;
738 	unsigned long flags;
739 	s32 delta;
740 
741 	delta = (s32) be32_to_cpu(rsp->req_lim_delta);
742 
743 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
744 
745 	target->req_lim += delta;
746 
747 	req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
748 
749 	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
750 		if (be32_to_cpu(rsp->resp_data_len) < 4)
751 			req->tsk_status = -1;
752 		else
753 			req->tsk_status = rsp->data[3];
754 		complete(&req->done);
755 	} else {
756 		scmnd = req->scmnd;
757 		if (!scmnd)
758 			printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
759 			       (unsigned long long) rsp->tag);
760 		scmnd->result = rsp->status;
761 
762 		if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
763 			memcpy(scmnd->sense_buffer, rsp->data +
764 			       be32_to_cpu(rsp->resp_data_len),
765 			       min_t(int, be32_to_cpu(rsp->sense_data_len),
766 				     SCSI_SENSE_BUFFERSIZE));
767 		}
768 
769 		if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
770 			scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
771 		else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
772 			scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
773 
774 		if (!req->tsk_mgmt) {
775 			scmnd->host_scribble = (void *) -1L;
776 			scmnd->scsi_done(scmnd);
777 
778 			srp_remove_req(target, req);
779 		} else
780 			req->cmd_done = 1;
781 	}
782 
783 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
784 }
785 
786 static void srp_reconnect_work(void *target_ptr)
787 {
788 	struct srp_target_port *target = target_ptr;
789 
790 	srp_reconnect_target(target);
791 }
792 
793 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
794 {
795 	struct srp_iu *iu;
796 	u8 opcode;
797 
798 	iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
799 
800 	dma_sync_single_for_cpu(target->srp_host->dev->dev->dma_device, iu->dma,
801 				target->max_ti_iu_len, DMA_FROM_DEVICE);
802 
803 	opcode = *(u8 *) iu->buf;
804 
805 	if (0) {
806 		int i;
807 
808 		printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
809 
810 		for (i = 0; i < wc->byte_len; ++i) {
811 			if (i % 8 == 0)
812 				printk(KERN_ERR "  [%02x] ", i);
813 			printk(" %02x", ((u8 *) iu->buf)[i]);
814 			if ((i + 1) % 8 == 0)
815 				printk("\n");
816 		}
817 
818 		if (wc->byte_len % 8)
819 			printk("\n");
820 	}
821 
822 	switch (opcode) {
823 	case SRP_RSP:
824 		srp_process_rsp(target, iu->buf);
825 		break;
826 
827 	case SRP_T_LOGOUT:
828 		/* XXX Handle target logout */
829 		printk(KERN_WARNING PFX "Got target logout request\n");
830 		break;
831 
832 	default:
833 		printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
834 		break;
835 	}
836 
837 	dma_sync_single_for_device(target->srp_host->dev->dev->dma_device, iu->dma,
838 				   target->max_ti_iu_len, DMA_FROM_DEVICE);
839 }
840 
841 static void srp_completion(struct ib_cq *cq, void *target_ptr)
842 {
843 	struct srp_target_port *target = target_ptr;
844 	struct ib_wc wc;
845 	unsigned long flags;
846 
847 	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
848 	while (ib_poll_cq(cq, 1, &wc) > 0) {
849 		if (wc.status) {
850 			printk(KERN_ERR PFX "failed %s status %d\n",
851 			       wc.wr_id & SRP_OP_RECV ? "receive" : "send",
852 			       wc.status);
853 			spin_lock_irqsave(target->scsi_host->host_lock, flags);
854 			if (target->state == SRP_TARGET_LIVE)
855 				schedule_work(&target->work);
856 			spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
857 			break;
858 		}
859 
860 		if (wc.wr_id & SRP_OP_RECV)
861 			srp_handle_recv(target, &wc);
862 		else
863 			++target->tx_tail;
864 	}
865 }
866 
867 static int __srp_post_recv(struct srp_target_port *target)
868 {
869 	struct srp_iu *iu;
870 	struct ib_sge list;
871 	struct ib_recv_wr wr, *bad_wr;
872 	unsigned int next;
873 	int ret;
874 
875 	next 	 = target->rx_head & (SRP_RQ_SIZE - 1);
876 	wr.wr_id = next | SRP_OP_RECV;
877 	iu 	 = target->rx_ring[next];
878 
879 	list.addr   = iu->dma;
880 	list.length = iu->size;
881 	list.lkey   = target->srp_host->dev->mr->lkey;
882 
883 	wr.next     = NULL;
884 	wr.sg_list  = &list;
885 	wr.num_sge  = 1;
886 
887 	ret = ib_post_recv(target->qp, &wr, &bad_wr);
888 	if (!ret)
889 		++target->rx_head;
890 
891 	return ret;
892 }
893 
894 static int srp_post_recv(struct srp_target_port *target)
895 {
896 	unsigned long flags;
897 	int ret;
898 
899 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
900 	ret = __srp_post_recv(target);
901 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
902 
903 	return ret;
904 }
905 
906 /*
907  * Must be called with target->scsi_host->host_lock held to protect
908  * req_lim and tx_head.  Lock cannot be dropped between call here and
909  * call to __srp_post_send().
910  */
911 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
912 {
913 	if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
914 		return NULL;
915 
916 	if (unlikely(target->req_lim < 1))
917 		++target->zero_req_lim;
918 
919 	return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
920 }
921 
922 /*
923  * Must be called with target->scsi_host->host_lock held to protect
924  * req_lim and tx_head.
925  */
926 static int __srp_post_send(struct srp_target_port *target,
927 			   struct srp_iu *iu, int len)
928 {
929 	struct ib_sge list;
930 	struct ib_send_wr wr, *bad_wr;
931 	int ret = 0;
932 
933 	list.addr   = iu->dma;
934 	list.length = len;
935 	list.lkey   = target->srp_host->dev->mr->lkey;
936 
937 	wr.next       = NULL;
938 	wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
939 	wr.sg_list    = &list;
940 	wr.num_sge    = 1;
941 	wr.opcode     = IB_WR_SEND;
942 	wr.send_flags = IB_SEND_SIGNALED;
943 
944 	ret = ib_post_send(target->qp, &wr, &bad_wr);
945 
946 	if (!ret) {
947 		++target->tx_head;
948 		--target->req_lim;
949 	}
950 
951 	return ret;
952 }
953 
954 static int srp_queuecommand(struct scsi_cmnd *scmnd,
955 			    void (*done)(struct scsi_cmnd *))
956 {
957 	struct srp_target_port *target = host_to_target(scmnd->device->host);
958 	struct srp_request *req;
959 	struct srp_iu *iu;
960 	struct srp_cmd *cmd;
961 	int len;
962 
963 	if (target->state == SRP_TARGET_CONNECTING)
964 		goto err;
965 
966 	if (target->state == SRP_TARGET_DEAD ||
967 	    target->state == SRP_TARGET_REMOVED) {
968 		scmnd->result = DID_BAD_TARGET << 16;
969 		done(scmnd);
970 		return 0;
971 	}
972 
973 	iu = __srp_get_tx_iu(target);
974 	if (!iu)
975 		goto err;
976 
977 	dma_sync_single_for_cpu(target->srp_host->dev->dev->dma_device, iu->dma,
978 				srp_max_iu_len, DMA_TO_DEVICE);
979 
980 	req = list_entry(target->free_reqs.next, struct srp_request, list);
981 
982 	scmnd->scsi_done     = done;
983 	scmnd->result        = 0;
984 	scmnd->host_scribble = (void *) (long) req->index;
985 
986 	cmd = iu->buf;
987 	memset(cmd, 0, sizeof *cmd);
988 
989 	cmd->opcode = SRP_CMD;
990 	cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
991 	cmd->tag    = req->index;
992 	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
993 
994 	req->scmnd    = scmnd;
995 	req->cmd      = iu;
996 	req->cmd_done = 0;
997 	req->tsk_mgmt = NULL;
998 
999 	len = srp_map_data(scmnd, target, req);
1000 	if (len < 0) {
1001 		printk(KERN_ERR PFX "Failed to map data\n");
1002 		goto err;
1003 	}
1004 
1005 	if (__srp_post_recv(target)) {
1006 		printk(KERN_ERR PFX "Recv failed\n");
1007 		goto err_unmap;
1008 	}
1009 
1010 	dma_sync_single_for_device(target->srp_host->dev->dev->dma_device, iu->dma,
1011 				   srp_max_iu_len, DMA_TO_DEVICE);
1012 
1013 	if (__srp_post_send(target, iu, len)) {
1014 		printk(KERN_ERR PFX "Send failed\n");
1015 		goto err_unmap;
1016 	}
1017 
1018 	list_move_tail(&req->list, &target->req_queue);
1019 
1020 	return 0;
1021 
1022 err_unmap:
1023 	srp_unmap_data(scmnd, target, req);
1024 
1025 err:
1026 	return SCSI_MLQUEUE_HOST_BUSY;
1027 }
1028 
1029 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1030 {
1031 	int i;
1032 
1033 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1034 		target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1035 						  target->max_ti_iu_len,
1036 						  GFP_KERNEL, DMA_FROM_DEVICE);
1037 		if (!target->rx_ring[i])
1038 			goto err;
1039 	}
1040 
1041 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1042 		target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1043 						  srp_max_iu_len,
1044 						  GFP_KERNEL, DMA_TO_DEVICE);
1045 		if (!target->tx_ring[i])
1046 			goto err;
1047 	}
1048 
1049 	return 0;
1050 
1051 err:
1052 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1053 		srp_free_iu(target->srp_host, target->rx_ring[i]);
1054 		target->rx_ring[i] = NULL;
1055 	}
1056 
1057 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1058 		srp_free_iu(target->srp_host, target->tx_ring[i]);
1059 		target->tx_ring[i] = NULL;
1060 	}
1061 
1062 	return -ENOMEM;
1063 }
1064 
1065 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1066 			       struct ib_cm_event *event,
1067 			       struct srp_target_port *target)
1068 {
1069 	struct ib_class_port_info *cpi;
1070 	int opcode;
1071 
1072 	switch (event->param.rej_rcvd.reason) {
1073 	case IB_CM_REJ_PORT_CM_REDIRECT:
1074 		cpi = event->param.rej_rcvd.ari;
1075 		target->path.dlid = cpi->redirect_lid;
1076 		target->path.pkey = cpi->redirect_pkey;
1077 		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1078 		memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1079 
1080 		target->status = target->path.dlid ?
1081 			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1082 		break;
1083 
1084 	case IB_CM_REJ_PORT_REDIRECT:
1085 		if (topspin_workarounds &&
1086 		    !memcmp(&target->ioc_guid, topspin_oui, 3)) {
1087 			/*
1088 			 * Topspin/Cisco SRP gateways incorrectly send
1089 			 * reject reason code 25 when they mean 24
1090 			 * (port redirect).
1091 			 */
1092 			memcpy(target->path.dgid.raw,
1093 			       event->param.rej_rcvd.ari, 16);
1094 
1095 			printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1096 			       (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1097 			       (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1098 
1099 			target->status = SRP_PORT_REDIRECT;
1100 		} else {
1101 			printk(KERN_WARNING "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1102 			target->status = -ECONNRESET;
1103 		}
1104 		break;
1105 
1106 	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1107 		printk(KERN_WARNING "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1108 		target->status = -ECONNRESET;
1109 		break;
1110 
1111 	case IB_CM_REJ_CONSUMER_DEFINED:
1112 		opcode = *(u8 *) event->private_data;
1113 		if (opcode == SRP_LOGIN_REJ) {
1114 			struct srp_login_rej *rej = event->private_data;
1115 			u32 reason = be32_to_cpu(rej->reason);
1116 
1117 			if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1118 				printk(KERN_WARNING PFX
1119 				       "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1120 			else
1121 				printk(KERN_WARNING PFX
1122 				       "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1123 		} else
1124 			printk(KERN_WARNING "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1125 			       " opcode 0x%02x\n", opcode);
1126 		target->status = -ECONNRESET;
1127 		break;
1128 
1129 	default:
1130 		printk(KERN_WARNING "  REJ reason 0x%x\n",
1131 		       event->param.rej_rcvd.reason);
1132 		target->status = -ECONNRESET;
1133 	}
1134 }
1135 
1136 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1137 {
1138 	struct srp_target_port *target = cm_id->context;
1139 	struct ib_qp_attr *qp_attr = NULL;
1140 	int attr_mask = 0;
1141 	int comp = 0;
1142 	int opcode = 0;
1143 
1144 	switch (event->event) {
1145 	case IB_CM_REQ_ERROR:
1146 		printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
1147 		comp = 1;
1148 		target->status = -ECONNRESET;
1149 		break;
1150 
1151 	case IB_CM_REP_RECEIVED:
1152 		comp = 1;
1153 		opcode = *(u8 *) event->private_data;
1154 
1155 		if (opcode == SRP_LOGIN_RSP) {
1156 			struct srp_login_rsp *rsp = event->private_data;
1157 
1158 			target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1159 			target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1160 
1161 			target->scsi_host->can_queue = min(target->req_lim,
1162 							   target->scsi_host->can_queue);
1163 		} else {
1164 			printk(KERN_WARNING PFX "Unhandled RSP opcode %#x\n", opcode);
1165 			target->status = -ECONNRESET;
1166 			break;
1167 		}
1168 
1169 		target->status = srp_alloc_iu_bufs(target);
1170 		if (target->status)
1171 			break;
1172 
1173 		qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1174 		if (!qp_attr) {
1175 			target->status = -ENOMEM;
1176 			break;
1177 		}
1178 
1179 		qp_attr->qp_state = IB_QPS_RTR;
1180 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1181 		if (target->status)
1182 			break;
1183 
1184 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1185 		if (target->status)
1186 			break;
1187 
1188 		target->status = srp_post_recv(target);
1189 		if (target->status)
1190 			break;
1191 
1192 		qp_attr->qp_state = IB_QPS_RTS;
1193 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1194 		if (target->status)
1195 			break;
1196 
1197 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1198 		if (target->status)
1199 			break;
1200 
1201 		target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1202 		if (target->status)
1203 			break;
1204 
1205 		break;
1206 
1207 	case IB_CM_REJ_RECEIVED:
1208 		printk(KERN_DEBUG PFX "REJ received\n");
1209 		comp = 1;
1210 
1211 		srp_cm_rej_handler(cm_id, event, target);
1212 		break;
1213 
1214 	case IB_CM_DREQ_RECEIVED:
1215 		printk(KERN_WARNING PFX "DREQ received - connection closed\n");
1216 		if (ib_send_cm_drep(cm_id, NULL, 0))
1217 			printk(KERN_ERR PFX "Sending CM DREP failed\n");
1218 		break;
1219 
1220 	case IB_CM_TIMEWAIT_EXIT:
1221 		printk(KERN_ERR PFX "connection closed\n");
1222 
1223 		comp = 1;
1224 		target->status = 0;
1225 		break;
1226 
1227 	case IB_CM_MRA_RECEIVED:
1228 	case IB_CM_DREQ_ERROR:
1229 	case IB_CM_DREP_RECEIVED:
1230 		break;
1231 
1232 	default:
1233 		printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
1234 		break;
1235 	}
1236 
1237 	if (comp)
1238 		complete(&target->done);
1239 
1240 	kfree(qp_attr);
1241 
1242 	return 0;
1243 }
1244 
1245 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1246 			     struct srp_request *req, u8 func)
1247 {
1248 	struct srp_iu *iu;
1249 	struct srp_tsk_mgmt *tsk_mgmt;
1250 
1251 	spin_lock_irq(target->scsi_host->host_lock);
1252 
1253 	if (target->state == SRP_TARGET_DEAD ||
1254 	    target->state == SRP_TARGET_REMOVED) {
1255 		req->scmnd->result = DID_BAD_TARGET << 16;
1256 		goto out;
1257 	}
1258 
1259 	init_completion(&req->done);
1260 
1261 	iu = __srp_get_tx_iu(target);
1262 	if (!iu)
1263 		goto out;
1264 
1265 	tsk_mgmt = iu->buf;
1266 	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1267 
1268 	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
1269 	tsk_mgmt->lun 		= cpu_to_be64((u64) req->scmnd->device->lun << 48);
1270 	tsk_mgmt->tag 		= req->index | SRP_TAG_TSK_MGMT;
1271 	tsk_mgmt->tsk_mgmt_func = func;
1272 	tsk_mgmt->task_tag 	= req->index;
1273 
1274 	if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1275 		goto out;
1276 
1277 	req->tsk_mgmt = iu;
1278 
1279 	spin_unlock_irq(target->scsi_host->host_lock);
1280 
1281 	if (!wait_for_completion_timeout(&req->done,
1282 					 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1283 		return -1;
1284 
1285 	return 0;
1286 
1287 out:
1288 	spin_unlock_irq(target->scsi_host->host_lock);
1289 	return -1;
1290 }
1291 
1292 static int srp_find_req(struct srp_target_port *target,
1293 			struct scsi_cmnd *scmnd,
1294 			struct srp_request **req)
1295 {
1296 	if (scmnd->host_scribble == (void *) -1L)
1297 		return -1;
1298 
1299 	*req = &target->req_ring[(long) scmnd->host_scribble];
1300 
1301 	return 0;
1302 }
1303 
1304 static int srp_abort(struct scsi_cmnd *scmnd)
1305 {
1306 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1307 	struct srp_request *req;
1308 	int ret = SUCCESS;
1309 
1310 	printk(KERN_ERR "SRP abort called\n");
1311 
1312 	if (srp_find_req(target, scmnd, &req))
1313 		return FAILED;
1314 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
1315 		return FAILED;
1316 
1317 	spin_lock_irq(target->scsi_host->host_lock);
1318 
1319 	if (req->cmd_done) {
1320 		srp_remove_req(target, req);
1321 		scmnd->scsi_done(scmnd);
1322 	} else if (!req->tsk_status) {
1323 		srp_remove_req(target, req);
1324 		scmnd->result = DID_ABORT << 16;
1325 	} else
1326 		ret = FAILED;
1327 
1328 	spin_unlock_irq(target->scsi_host->host_lock);
1329 
1330 	return ret;
1331 }
1332 
1333 static int srp_reset_device(struct scsi_cmnd *scmnd)
1334 {
1335 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1336 	struct srp_request *req, *tmp;
1337 
1338 	printk(KERN_ERR "SRP reset_device called\n");
1339 
1340 	if (srp_find_req(target, scmnd, &req))
1341 		return FAILED;
1342 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
1343 		return FAILED;
1344 	if (req->tsk_status)
1345 		return FAILED;
1346 
1347 	spin_lock_irq(target->scsi_host->host_lock);
1348 
1349 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
1350 		if (req->scmnd->device == scmnd->device)
1351 			srp_reset_req(target, req);
1352 
1353 	spin_unlock_irq(target->scsi_host->host_lock);
1354 
1355 	return SUCCESS;
1356 }
1357 
1358 static int srp_reset_host(struct scsi_cmnd *scmnd)
1359 {
1360 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1361 	int ret = FAILED;
1362 
1363 	printk(KERN_ERR PFX "SRP reset_host called\n");
1364 
1365 	if (!srp_reconnect_target(target))
1366 		ret = SUCCESS;
1367 
1368 	return ret;
1369 }
1370 
1371 static ssize_t show_id_ext(struct class_device *cdev, char *buf)
1372 {
1373 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1374 
1375 	if (target->state == SRP_TARGET_DEAD ||
1376 	    target->state == SRP_TARGET_REMOVED)
1377 		return -ENODEV;
1378 
1379 	return sprintf(buf, "0x%016llx\n",
1380 		       (unsigned long long) be64_to_cpu(target->id_ext));
1381 }
1382 
1383 static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
1384 {
1385 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1386 
1387 	if (target->state == SRP_TARGET_DEAD ||
1388 	    target->state == SRP_TARGET_REMOVED)
1389 		return -ENODEV;
1390 
1391 	return sprintf(buf, "0x%016llx\n",
1392 		       (unsigned long long) be64_to_cpu(target->ioc_guid));
1393 }
1394 
1395 static ssize_t show_service_id(struct class_device *cdev, char *buf)
1396 {
1397 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1398 
1399 	if (target->state == SRP_TARGET_DEAD ||
1400 	    target->state == SRP_TARGET_REMOVED)
1401 		return -ENODEV;
1402 
1403 	return sprintf(buf, "0x%016llx\n",
1404 		       (unsigned long long) be64_to_cpu(target->service_id));
1405 }
1406 
1407 static ssize_t show_pkey(struct class_device *cdev, char *buf)
1408 {
1409 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1410 
1411 	if (target->state == SRP_TARGET_DEAD ||
1412 	    target->state == SRP_TARGET_REMOVED)
1413 		return -ENODEV;
1414 
1415 	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1416 }
1417 
1418 static ssize_t show_dgid(struct class_device *cdev, char *buf)
1419 {
1420 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1421 
1422 	if (target->state == SRP_TARGET_DEAD ||
1423 	    target->state == SRP_TARGET_REMOVED)
1424 		return -ENODEV;
1425 
1426 	return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1427 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
1428 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
1429 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
1430 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
1431 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
1432 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
1433 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
1434 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
1435 }
1436 
1437 static ssize_t show_zero_req_lim(struct class_device *cdev, char *buf)
1438 {
1439 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1440 
1441 	if (target->state == SRP_TARGET_DEAD ||
1442 	    target->state == SRP_TARGET_REMOVED)
1443 		return -ENODEV;
1444 
1445 	return sprintf(buf, "%d\n", target->zero_req_lim);
1446 }
1447 
1448 static CLASS_DEVICE_ATTR(id_ext,	S_IRUGO, show_id_ext,		NULL);
1449 static CLASS_DEVICE_ATTR(ioc_guid,	S_IRUGO, show_ioc_guid,		NULL);
1450 static CLASS_DEVICE_ATTR(service_id,	S_IRUGO, show_service_id,	NULL);
1451 static CLASS_DEVICE_ATTR(pkey,		S_IRUGO, show_pkey,		NULL);
1452 static CLASS_DEVICE_ATTR(dgid,		S_IRUGO, show_dgid,		NULL);
1453 static CLASS_DEVICE_ATTR(zero_req_lim,	S_IRUGO, show_zero_req_lim,	NULL);
1454 
1455 static struct class_device_attribute *srp_host_attrs[] = {
1456 	&class_device_attr_id_ext,
1457 	&class_device_attr_ioc_guid,
1458 	&class_device_attr_service_id,
1459 	&class_device_attr_pkey,
1460 	&class_device_attr_dgid,
1461 	&class_device_attr_zero_req_lim,
1462 	NULL
1463 };
1464 
1465 static struct scsi_host_template srp_template = {
1466 	.module				= THIS_MODULE,
1467 	.name				= DRV_NAME,
1468 	.info				= srp_target_info,
1469 	.queuecommand			= srp_queuecommand,
1470 	.eh_abort_handler		= srp_abort,
1471 	.eh_device_reset_handler	= srp_reset_device,
1472 	.eh_host_reset_handler		= srp_reset_host,
1473 	.can_queue			= SRP_SQ_SIZE,
1474 	.this_id			= -1,
1475 	.cmd_per_lun			= SRP_SQ_SIZE,
1476 	.use_clustering			= ENABLE_CLUSTERING,
1477 	.shost_attrs			= srp_host_attrs
1478 };
1479 
1480 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1481 {
1482 	sprintf(target->target_name, "SRP.T10:%016llX",
1483 		 (unsigned long long) be64_to_cpu(target->id_ext));
1484 
1485 	if (scsi_add_host(target->scsi_host, host->dev->dev->dma_device))
1486 		return -ENODEV;
1487 
1488 	spin_lock(&host->target_lock);
1489 	list_add_tail(&target->list, &host->target_list);
1490 	spin_unlock(&host->target_lock);
1491 
1492 	target->state = SRP_TARGET_LIVE;
1493 
1494 	scsi_scan_target(&target->scsi_host->shost_gendev,
1495 			 0, target->scsi_id, SCAN_WILD_CARD, 0);
1496 
1497 	return 0;
1498 }
1499 
1500 static void srp_release_class_dev(struct class_device *class_dev)
1501 {
1502 	struct srp_host *host =
1503 		container_of(class_dev, struct srp_host, class_dev);
1504 
1505 	complete(&host->released);
1506 }
1507 
1508 static struct class srp_class = {
1509 	.name    = "infiniband_srp",
1510 	.release = srp_release_class_dev
1511 };
1512 
1513 /*
1514  * Target ports are added by writing
1515  *
1516  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1517  *     pkey=<P_Key>,service_id=<service ID>
1518  *
1519  * to the add_target sysfs attribute.
1520  */
1521 enum {
1522 	SRP_OPT_ERR		= 0,
1523 	SRP_OPT_ID_EXT		= 1 << 0,
1524 	SRP_OPT_IOC_GUID	= 1 << 1,
1525 	SRP_OPT_DGID		= 1 << 2,
1526 	SRP_OPT_PKEY		= 1 << 3,
1527 	SRP_OPT_SERVICE_ID	= 1 << 4,
1528 	SRP_OPT_MAX_SECT	= 1 << 5,
1529 	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
1530 	SRP_OPT_IO_CLASS	= 1 << 7,
1531 	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
1532 				   SRP_OPT_IOC_GUID	|
1533 				   SRP_OPT_DGID		|
1534 				   SRP_OPT_PKEY		|
1535 				   SRP_OPT_SERVICE_ID),
1536 };
1537 
1538 static match_table_t srp_opt_tokens = {
1539 	{ SRP_OPT_ID_EXT,		"id_ext=%s" 		},
1540 	{ SRP_OPT_IOC_GUID,		"ioc_guid=%s" 		},
1541 	{ SRP_OPT_DGID,			"dgid=%s" 		},
1542 	{ SRP_OPT_PKEY,			"pkey=%x" 		},
1543 	{ SRP_OPT_SERVICE_ID,		"service_id=%s"		},
1544 	{ SRP_OPT_MAX_SECT,		"max_sect=%d" 		},
1545 	{ SRP_OPT_MAX_CMD_PER_LUN,	"max_cmd_per_lun=%d" 	},
1546 	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
1547 	{ SRP_OPT_ERR,			NULL 			}
1548 };
1549 
1550 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1551 {
1552 	char *options, *sep_opt;
1553 	char *p;
1554 	char dgid[3];
1555 	substring_t args[MAX_OPT_ARGS];
1556 	int opt_mask = 0;
1557 	int token;
1558 	int ret = -EINVAL;
1559 	int i;
1560 
1561 	options = kstrdup(buf, GFP_KERNEL);
1562 	if (!options)
1563 		return -ENOMEM;
1564 
1565 	sep_opt = options;
1566 	while ((p = strsep(&sep_opt, ",")) != NULL) {
1567 		if (!*p)
1568 			continue;
1569 
1570 		token = match_token(p, srp_opt_tokens, args);
1571 		opt_mask |= token;
1572 
1573 		switch (token) {
1574 		case SRP_OPT_ID_EXT:
1575 			p = match_strdup(args);
1576 			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1577 			kfree(p);
1578 			break;
1579 
1580 		case SRP_OPT_IOC_GUID:
1581 			p = match_strdup(args);
1582 			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1583 			kfree(p);
1584 			break;
1585 
1586 		case SRP_OPT_DGID:
1587 			p = match_strdup(args);
1588 			if (strlen(p) != 32) {
1589 				printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1590 				kfree(p);
1591 				goto out;
1592 			}
1593 
1594 			for (i = 0; i < 16; ++i) {
1595 				strlcpy(dgid, p + i * 2, 3);
1596 				target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1597 			}
1598 			kfree(p);
1599 			break;
1600 
1601 		case SRP_OPT_PKEY:
1602 			if (match_hex(args, &token)) {
1603 				printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1604 				goto out;
1605 			}
1606 			target->path.pkey = cpu_to_be16(token);
1607 			break;
1608 
1609 		case SRP_OPT_SERVICE_ID:
1610 			p = match_strdup(args);
1611 			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1612 			kfree(p);
1613 			break;
1614 
1615 		case SRP_OPT_MAX_SECT:
1616 			if (match_int(args, &token)) {
1617 				printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1618 				goto out;
1619 			}
1620 			target->scsi_host->max_sectors = token;
1621 			break;
1622 
1623 		case SRP_OPT_MAX_CMD_PER_LUN:
1624 			if (match_int(args, &token)) {
1625 				printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
1626 				goto out;
1627 			}
1628 			target->scsi_host->cmd_per_lun = min(token, SRP_SQ_SIZE);
1629 			break;
1630 
1631 		case SRP_OPT_IO_CLASS:
1632 			if (match_hex(args, &token)) {
1633 				printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
1634 				goto out;
1635 			}
1636 			if (token != SRP_REV10_IB_IO_CLASS &&
1637 			    token != SRP_REV16A_IB_IO_CLASS) {
1638 				printk(KERN_WARNING PFX "unknown IO class parameter value"
1639 				       " %x specified (use %x or %x).\n",
1640 				       token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
1641 				goto out;
1642 			}
1643 			target->io_class = token;
1644 			break;
1645 
1646 		default:
1647 			printk(KERN_WARNING PFX "unknown parameter or missing value "
1648 			       "'%s' in target creation request\n", p);
1649 			goto out;
1650 		}
1651 	}
1652 
1653 	if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1654 		ret = 0;
1655 	else
1656 		for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1657 			if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1658 			    !(srp_opt_tokens[i].token & opt_mask))
1659 				printk(KERN_WARNING PFX "target creation request is "
1660 				       "missing parameter '%s'\n",
1661 				       srp_opt_tokens[i].pattern);
1662 
1663 out:
1664 	kfree(options);
1665 	return ret;
1666 }
1667 
1668 static ssize_t srp_create_target(struct class_device *class_dev,
1669 				 const char *buf, size_t count)
1670 {
1671 	struct srp_host *host =
1672 		container_of(class_dev, struct srp_host, class_dev);
1673 	struct Scsi_Host *target_host;
1674 	struct srp_target_port *target;
1675 	int ret;
1676 	int i;
1677 
1678 	target_host = scsi_host_alloc(&srp_template,
1679 				      sizeof (struct srp_target_port));
1680 	if (!target_host)
1681 		return -ENOMEM;
1682 
1683 	target_host->max_lun = SRP_MAX_LUN;
1684 
1685 	target = host_to_target(target_host);
1686 	memset(target, 0, sizeof *target);
1687 
1688 	target->io_class   = SRP_REV16A_IB_IO_CLASS;
1689 	target->scsi_host  = target_host;
1690 	target->srp_host   = host;
1691 
1692 	INIT_WORK(&target->work, srp_reconnect_work, target);
1693 
1694 	INIT_LIST_HEAD(&target->free_reqs);
1695 	INIT_LIST_HEAD(&target->req_queue);
1696 	for (i = 0; i < SRP_SQ_SIZE; ++i) {
1697 		target->req_ring[i].index = i;
1698 		list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1699 	}
1700 
1701 	ret = srp_parse_options(buf, target);
1702 	if (ret)
1703 		goto err;
1704 
1705 	ib_get_cached_gid(host->dev->dev, host->port, 0, &target->path.sgid);
1706 
1707 	printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1708 	       "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1709 	       (unsigned long long) be64_to_cpu(target->id_ext),
1710 	       (unsigned long long) be64_to_cpu(target->ioc_guid),
1711 	       be16_to_cpu(target->path.pkey),
1712 	       (unsigned long long) be64_to_cpu(target->service_id),
1713 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1714 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1715 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1716 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1717 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1718 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1719 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1720 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1721 
1722 	ret = srp_create_target_ib(target);
1723 	if (ret)
1724 		goto err;
1725 
1726 	target->cm_id = ib_create_cm_id(host->dev->dev, srp_cm_handler, target);
1727 	if (IS_ERR(target->cm_id)) {
1728 		ret = PTR_ERR(target->cm_id);
1729 		goto err_free;
1730 	}
1731 
1732 	ret = srp_connect_target(target);
1733 	if (ret) {
1734 		printk(KERN_ERR PFX "Connection failed\n");
1735 		goto err_cm_id;
1736 	}
1737 
1738 	ret = srp_add_target(host, target);
1739 	if (ret)
1740 		goto err_disconnect;
1741 
1742 	return count;
1743 
1744 err_disconnect:
1745 	srp_disconnect_target(target);
1746 
1747 err_cm_id:
1748 	ib_destroy_cm_id(target->cm_id);
1749 
1750 err_free:
1751 	srp_free_target_ib(target);
1752 
1753 err:
1754 	scsi_host_put(target_host);
1755 
1756 	return ret;
1757 }
1758 
1759 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1760 
1761 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1762 {
1763 	struct srp_host *host =
1764 		container_of(class_dev, struct srp_host, class_dev);
1765 
1766 	return sprintf(buf, "%s\n", host->dev->dev->name);
1767 }
1768 
1769 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1770 
1771 static ssize_t show_port(struct class_device *class_dev, char *buf)
1772 {
1773 	struct srp_host *host =
1774 		container_of(class_dev, struct srp_host, class_dev);
1775 
1776 	return sprintf(buf, "%d\n", host->port);
1777 }
1778 
1779 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1780 
1781 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
1782 {
1783 	struct srp_host *host;
1784 
1785 	host = kzalloc(sizeof *host, GFP_KERNEL);
1786 	if (!host)
1787 		return NULL;
1788 
1789 	INIT_LIST_HEAD(&host->target_list);
1790 	spin_lock_init(&host->target_lock);
1791 	init_completion(&host->released);
1792 	host->dev  = device;
1793 	host->port = port;
1794 
1795 	host->initiator_port_id[7] = port;
1796 	memcpy(host->initiator_port_id + 8, &device->dev->node_guid, 8);
1797 
1798 	host->class_dev.class = &srp_class;
1799 	host->class_dev.dev   = device->dev->dma_device;
1800 	snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1801 		 device->dev->name, port);
1802 
1803 	if (class_device_register(&host->class_dev))
1804 		goto free_host;
1805 	if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1806 		goto err_class;
1807 	if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1808 		goto err_class;
1809 	if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1810 		goto err_class;
1811 
1812 	return host;
1813 
1814 err_class:
1815 	class_device_unregister(&host->class_dev);
1816 
1817 free_host:
1818 	kfree(host);
1819 
1820 	return NULL;
1821 }
1822 
1823 static void srp_add_one(struct ib_device *device)
1824 {
1825 	struct srp_device *srp_dev;
1826 	struct ib_device_attr *dev_attr;
1827 	struct ib_fmr_pool_param fmr_param;
1828 	struct srp_host *host;
1829 	int s, e, p;
1830 
1831 	dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
1832 	if (!dev_attr)
1833 		return;
1834 
1835 	if (ib_query_device(device, dev_attr)) {
1836 		printk(KERN_WARNING PFX "Query device failed for %s\n",
1837 		       device->name);
1838 		goto free_attr;
1839 	}
1840 
1841 	srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
1842 	if (!srp_dev)
1843 		goto free_attr;
1844 
1845 	/*
1846 	 * Use the smallest page size supported by the HCA, down to a
1847 	 * minimum of 512 bytes (which is the smallest sector that a
1848 	 * SCSI command will ever carry).
1849 	 */
1850 	srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
1851 	srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
1852 	srp_dev->fmr_page_mask  = ~((unsigned long) srp_dev->fmr_page_size - 1);
1853 
1854 	INIT_LIST_HEAD(&srp_dev->dev_list);
1855 
1856 	srp_dev->dev = device;
1857 	srp_dev->pd  = ib_alloc_pd(device);
1858 	if (IS_ERR(srp_dev->pd))
1859 		goto free_dev;
1860 
1861 	srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
1862 				    IB_ACCESS_LOCAL_WRITE |
1863 				    IB_ACCESS_REMOTE_READ |
1864 				    IB_ACCESS_REMOTE_WRITE);
1865 	if (IS_ERR(srp_dev->mr))
1866 		goto err_pd;
1867 
1868 	memset(&fmr_param, 0, sizeof fmr_param);
1869 	fmr_param.pool_size	    = SRP_FMR_POOL_SIZE;
1870 	fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
1871 	fmr_param.cache		    = 1;
1872 	fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
1873 	fmr_param.page_shift	    = srp_dev->fmr_page_shift;
1874 	fmr_param.access	    = (IB_ACCESS_LOCAL_WRITE |
1875 				       IB_ACCESS_REMOTE_WRITE |
1876 				       IB_ACCESS_REMOTE_READ);
1877 
1878 	srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
1879 	if (IS_ERR(srp_dev->fmr_pool))
1880 		srp_dev->fmr_pool = NULL;
1881 
1882 	if (device->node_type == IB_NODE_SWITCH) {
1883 		s = 0;
1884 		e = 0;
1885 	} else {
1886 		s = 1;
1887 		e = device->phys_port_cnt;
1888 	}
1889 
1890 	for (p = s; p <= e; ++p) {
1891 		host = srp_add_port(srp_dev, p);
1892 		if (host)
1893 			list_add_tail(&host->list, &srp_dev->dev_list);
1894 	}
1895 
1896 	ib_set_client_data(device, &srp_client, srp_dev);
1897 
1898 	goto free_attr;
1899 
1900 err_pd:
1901 	ib_dealloc_pd(srp_dev->pd);
1902 
1903 free_dev:
1904 	kfree(srp_dev);
1905 
1906 free_attr:
1907 	kfree(dev_attr);
1908 }
1909 
1910 static void srp_remove_one(struct ib_device *device)
1911 {
1912 	struct srp_device *srp_dev;
1913 	struct srp_host *host, *tmp_host;
1914 	LIST_HEAD(target_list);
1915 	struct srp_target_port *target, *tmp_target;
1916 
1917 	srp_dev = ib_get_client_data(device, &srp_client);
1918 
1919 	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
1920 		class_device_unregister(&host->class_dev);
1921 		/*
1922 		 * Wait for the sysfs entry to go away, so that no new
1923 		 * target ports can be created.
1924 		 */
1925 		wait_for_completion(&host->released);
1926 
1927 		/*
1928 		 * Mark all target ports as removed, so we stop queueing
1929 		 * commands and don't try to reconnect.
1930 		 */
1931 		spin_lock(&host->target_lock);
1932 		list_for_each_entry(target, &host->target_list, list) {
1933 			spin_lock_irq(target->scsi_host->host_lock);
1934 			target->state = SRP_TARGET_REMOVED;
1935 			spin_unlock_irq(target->scsi_host->host_lock);
1936 		}
1937 		spin_unlock(&host->target_lock);
1938 
1939 		/*
1940 		 * Wait for any reconnection tasks that may have
1941 		 * started before we marked our target ports as
1942 		 * removed, and any target port removal tasks.
1943 		 */
1944 		flush_scheduled_work();
1945 
1946 		list_for_each_entry_safe(target, tmp_target,
1947 					 &host->target_list, list) {
1948 			scsi_remove_host(target->scsi_host);
1949 			srp_disconnect_target(target);
1950 			ib_destroy_cm_id(target->cm_id);
1951 			srp_free_target_ib(target);
1952 			scsi_host_put(target->scsi_host);
1953 		}
1954 
1955 		kfree(host);
1956 	}
1957 
1958 	if (srp_dev->fmr_pool)
1959 		ib_destroy_fmr_pool(srp_dev->fmr_pool);
1960 	ib_dereg_mr(srp_dev->mr);
1961 	ib_dealloc_pd(srp_dev->pd);
1962 
1963 	kfree(srp_dev);
1964 }
1965 
1966 static int __init srp_init_module(void)
1967 {
1968 	int ret;
1969 
1970 	srp_template.sg_tablesize = srp_sg_tablesize;
1971 	srp_max_iu_len = (sizeof (struct srp_cmd) +
1972 			  sizeof (struct srp_indirect_buf) +
1973 			  srp_sg_tablesize * 16);
1974 
1975 	ret = class_register(&srp_class);
1976 	if (ret) {
1977 		printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
1978 		return ret;
1979 	}
1980 
1981 	ret = ib_register_client(&srp_client);
1982 	if (ret) {
1983 		printk(KERN_ERR PFX "couldn't register IB client\n");
1984 		class_unregister(&srp_class);
1985 		return ret;
1986 	}
1987 
1988 	return 0;
1989 }
1990 
1991 static void __exit srp_cleanup_module(void)
1992 {
1993 	ib_unregister_client(&srp_client);
1994 	class_unregister(&srp_class);
1995 }
1996 
1997 module_init(srp_init_module);
1998 module_exit(srp_cleanup_module);
1999