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 int mellanox_workarounds = 1;
81 
82 module_param(mellanox_workarounds, int, 0444);
83 MODULE_PARM_DESC(mellanox_workarounds,
84 		 "Enable workarounds for Mellanox SRP target bugs if != 0");
85 
86 static const u8 mellanox_oui[3] = { 0x00, 0x02, 0xc9 };
87 
88 static void srp_add_one(struct ib_device *device);
89 static void srp_remove_one(struct ib_device *device);
90 static void srp_completion(struct ib_cq *cq, void *target_ptr);
91 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
92 
93 static struct ib_client srp_client = {
94 	.name   = "srp",
95 	.add    = srp_add_one,
96 	.remove = srp_remove_one
97 };
98 
99 static struct ib_sa_client srp_sa_client;
100 
101 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
102 {
103 	return (struct srp_target_port *) host->hostdata;
104 }
105 
106 static const char *srp_target_info(struct Scsi_Host *host)
107 {
108 	return host_to_target(host)->target_name;
109 }
110 
111 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
112 				   gfp_t gfp_mask,
113 				   enum dma_data_direction direction)
114 {
115 	struct srp_iu *iu;
116 
117 	iu = kmalloc(sizeof *iu, gfp_mask);
118 	if (!iu)
119 		goto out;
120 
121 	iu->buf = kzalloc(size, gfp_mask);
122 	if (!iu->buf)
123 		goto out_free_iu;
124 
125 	iu->dma = ib_dma_map_single(host->dev->dev, iu->buf, size, direction);
126 	if (ib_dma_mapping_error(host->dev->dev, iu->dma))
127 		goto out_free_buf;
128 
129 	iu->size      = size;
130 	iu->direction = direction;
131 
132 	return iu;
133 
134 out_free_buf:
135 	kfree(iu->buf);
136 out_free_iu:
137 	kfree(iu);
138 out:
139 	return NULL;
140 }
141 
142 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
143 {
144 	if (!iu)
145 		return;
146 
147 	ib_dma_unmap_single(host->dev->dev, iu->dma, iu->size, iu->direction);
148 	kfree(iu->buf);
149 	kfree(iu);
150 }
151 
152 static void srp_qp_event(struct ib_event *event, void *context)
153 {
154 	printk(KERN_ERR PFX "QP event %d\n", event->event);
155 }
156 
157 static int srp_init_qp(struct srp_target_port *target,
158 		       struct ib_qp *qp)
159 {
160 	struct ib_qp_attr *attr;
161 	int ret;
162 
163 	attr = kmalloc(sizeof *attr, GFP_KERNEL);
164 	if (!attr)
165 		return -ENOMEM;
166 
167 	ret = ib_find_cached_pkey(target->srp_host->dev->dev,
168 				  target->srp_host->port,
169 				  be16_to_cpu(target->path.pkey),
170 				  &attr->pkey_index);
171 	if (ret)
172 		goto out;
173 
174 	attr->qp_state        = IB_QPS_INIT;
175 	attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
176 				    IB_ACCESS_REMOTE_WRITE);
177 	attr->port_num        = target->srp_host->port;
178 
179 	ret = ib_modify_qp(qp, attr,
180 			   IB_QP_STATE		|
181 			   IB_QP_PKEY_INDEX	|
182 			   IB_QP_ACCESS_FLAGS	|
183 			   IB_QP_PORT);
184 
185 out:
186 	kfree(attr);
187 	return ret;
188 }
189 
190 static int srp_create_target_ib(struct srp_target_port *target)
191 {
192 	struct ib_qp_init_attr *init_attr;
193 	int ret;
194 
195 	init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
196 	if (!init_attr)
197 		return -ENOMEM;
198 
199 	target->cq = ib_create_cq(target->srp_host->dev->dev, srp_completion,
200 				  NULL, target, SRP_CQ_SIZE, 0);
201 	if (IS_ERR(target->cq)) {
202 		ret = PTR_ERR(target->cq);
203 		goto out;
204 	}
205 
206 	ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
207 
208 	init_attr->event_handler       = srp_qp_event;
209 	init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
210 	init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
211 	init_attr->cap.max_recv_sge    = 1;
212 	init_attr->cap.max_send_sge    = 1;
213 	init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
214 	init_attr->qp_type             = IB_QPT_RC;
215 	init_attr->send_cq             = target->cq;
216 	init_attr->recv_cq             = target->cq;
217 
218 	target->qp = ib_create_qp(target->srp_host->dev->pd, init_attr);
219 	if (IS_ERR(target->qp)) {
220 		ret = PTR_ERR(target->qp);
221 		ib_destroy_cq(target->cq);
222 		goto out;
223 	}
224 
225 	ret = srp_init_qp(target, target->qp);
226 	if (ret) {
227 		ib_destroy_qp(target->qp);
228 		ib_destroy_cq(target->cq);
229 		goto out;
230 	}
231 
232 out:
233 	kfree(init_attr);
234 	return ret;
235 }
236 
237 static void srp_free_target_ib(struct srp_target_port *target)
238 {
239 	int i;
240 
241 	ib_destroy_qp(target->qp);
242 	ib_destroy_cq(target->cq);
243 
244 	for (i = 0; i < SRP_RQ_SIZE; ++i)
245 		srp_free_iu(target->srp_host, target->rx_ring[i]);
246 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
247 		srp_free_iu(target->srp_host, target->tx_ring[i]);
248 }
249 
250 static void srp_path_rec_completion(int status,
251 				    struct ib_sa_path_rec *pathrec,
252 				    void *target_ptr)
253 {
254 	struct srp_target_port *target = target_ptr;
255 
256 	target->status = status;
257 	if (status)
258 		printk(KERN_ERR PFX "Got failed path rec status %d\n", status);
259 	else
260 		target->path = *pathrec;
261 	complete(&target->done);
262 }
263 
264 static int srp_lookup_path(struct srp_target_port *target)
265 {
266 	target->path.numb_path = 1;
267 
268 	init_completion(&target->done);
269 
270 	target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
271 						   target->srp_host->dev->dev,
272 						   target->srp_host->port,
273 						   &target->path,
274 						   IB_SA_PATH_REC_DGID		|
275 						   IB_SA_PATH_REC_SGID		|
276 						   IB_SA_PATH_REC_NUMB_PATH	|
277 						   IB_SA_PATH_REC_PKEY,
278 						   SRP_PATH_REC_TIMEOUT_MS,
279 						   GFP_KERNEL,
280 						   srp_path_rec_completion,
281 						   target, &target->path_query);
282 	if (target->path_query_id < 0)
283 		return target->path_query_id;
284 
285 	wait_for_completion(&target->done);
286 
287 	if (target->status < 0)
288 		printk(KERN_WARNING PFX "Path record query failed\n");
289 
290 	return target->status;
291 }
292 
293 static int srp_send_req(struct srp_target_port *target)
294 {
295 	struct {
296 		struct ib_cm_req_param param;
297 		struct srp_login_req   priv;
298 	} *req = NULL;
299 	int status;
300 
301 	req = kzalloc(sizeof *req, GFP_KERNEL);
302 	if (!req)
303 		return -ENOMEM;
304 
305 	req->param.primary_path 	      = &target->path;
306 	req->param.alternate_path 	      = NULL;
307 	req->param.service_id 		      = target->service_id;
308 	req->param.qp_num 		      = target->qp->qp_num;
309 	req->param.qp_type 		      = target->qp->qp_type;
310 	req->param.private_data 	      = &req->priv;
311 	req->param.private_data_len 	      = sizeof req->priv;
312 	req->param.flow_control 	      = 1;
313 
314 	get_random_bytes(&req->param.starting_psn, 4);
315 	req->param.starting_psn 	     &= 0xffffff;
316 
317 	/*
318 	 * Pick some arbitrary defaults here; we could make these
319 	 * module parameters if anyone cared about setting them.
320 	 */
321 	req->param.responder_resources	      = 4;
322 	req->param.remote_cm_response_timeout = 20;
323 	req->param.local_cm_response_timeout  = 20;
324 	req->param.retry_count 		      = 7;
325 	req->param.rnr_retry_count 	      = 7;
326 	req->param.max_cm_retries 	      = 15;
327 
328 	req->priv.opcode     	= SRP_LOGIN_REQ;
329 	req->priv.tag        	= 0;
330 	req->priv.req_it_iu_len = cpu_to_be32(srp_max_iu_len);
331 	req->priv.req_buf_fmt 	= cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
332 					      SRP_BUF_FORMAT_INDIRECT);
333 	/*
334 	 * In the published SRP specification (draft rev. 16a), the
335 	 * port identifier format is 8 bytes of ID extension followed
336 	 * by 8 bytes of GUID.  Older drafts put the two halves in the
337 	 * opposite order, so that the GUID comes first.
338 	 *
339 	 * Targets conforming to these obsolete drafts can be
340 	 * recognized by the I/O Class they report.
341 	 */
342 	if (target->io_class == SRP_REV10_IB_IO_CLASS) {
343 		memcpy(req->priv.initiator_port_id,
344 		       &target->path.sgid.global.interface_id, 8);
345 		memcpy(req->priv.initiator_port_id + 8,
346 		       &target->initiator_ext, 8);
347 		memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
348 		memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
349 	} else {
350 		memcpy(req->priv.initiator_port_id,
351 		       &target->initiator_ext, 8);
352 		memcpy(req->priv.initiator_port_id + 8,
353 		       &target->path.sgid.global.interface_id, 8);
354 		memcpy(req->priv.target_port_id,     &target->id_ext, 8);
355 		memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
356 	}
357 
358 	/*
359 	 * Topspin/Cisco SRP targets will reject our login unless we
360 	 * zero out the first 8 bytes of our initiator port ID and set
361 	 * the second 8 bytes to the local node GUID.
362 	 */
363 	if (topspin_workarounds && !memcmp(&target->ioc_guid, topspin_oui, 3)) {
364 		printk(KERN_DEBUG PFX "Topspin/Cisco initiator port ID workaround "
365 		       "activated for target GUID %016llx\n",
366 		       (unsigned long long) be64_to_cpu(target->ioc_guid));
367 		memset(req->priv.initiator_port_id, 0, 8);
368 		memcpy(req->priv.initiator_port_id + 8,
369 		       &target->srp_host->dev->dev->node_guid, 8);
370 	}
371 
372 	status = ib_send_cm_req(target->cm_id, &req->param);
373 
374 	kfree(req);
375 
376 	return status;
377 }
378 
379 static void srp_disconnect_target(struct srp_target_port *target)
380 {
381 	/* XXX should send SRP_I_LOGOUT request */
382 
383 	init_completion(&target->done);
384 	if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
385 		printk(KERN_DEBUG PFX "Sending CM DREQ failed\n");
386 		return;
387 	}
388 	wait_for_completion(&target->done);
389 }
390 
391 static void srp_remove_work(struct work_struct *work)
392 {
393 	struct srp_target_port *target =
394 		container_of(work, struct srp_target_port, work);
395 
396 	spin_lock_irq(target->scsi_host->host_lock);
397 	if (target->state != SRP_TARGET_DEAD) {
398 		spin_unlock_irq(target->scsi_host->host_lock);
399 		return;
400 	}
401 	target->state = SRP_TARGET_REMOVED;
402 	spin_unlock_irq(target->scsi_host->host_lock);
403 
404 	spin_lock(&target->srp_host->target_lock);
405 	list_del(&target->list);
406 	spin_unlock(&target->srp_host->target_lock);
407 
408 	scsi_remove_host(target->scsi_host);
409 	ib_destroy_cm_id(target->cm_id);
410 	srp_free_target_ib(target);
411 	scsi_host_put(target->scsi_host);
412 }
413 
414 static int srp_connect_target(struct srp_target_port *target)
415 {
416 	int ret;
417 
418 	ret = srp_lookup_path(target);
419 	if (ret)
420 		return ret;
421 
422 	while (1) {
423 		init_completion(&target->done);
424 		ret = srp_send_req(target);
425 		if (ret)
426 			return ret;
427 		wait_for_completion(&target->done);
428 
429 		/*
430 		 * The CM event handling code will set status to
431 		 * SRP_PORT_REDIRECT if we get a port redirect REJ
432 		 * back, or SRP_DLID_REDIRECT if we get a lid/qp
433 		 * redirect REJ back.
434 		 */
435 		switch (target->status) {
436 		case 0:
437 			return 0;
438 
439 		case SRP_PORT_REDIRECT:
440 			ret = srp_lookup_path(target);
441 			if (ret)
442 				return ret;
443 			break;
444 
445 		case SRP_DLID_REDIRECT:
446 			break;
447 
448 		default:
449 			return target->status;
450 		}
451 	}
452 }
453 
454 static void srp_unmap_data(struct scsi_cmnd *scmnd,
455 			   struct srp_target_port *target,
456 			   struct srp_request *req)
457 {
458 	struct scatterlist *scat;
459 	int nents;
460 
461 	if (!scmnd->request_buffer ||
462 	    (scmnd->sc_data_direction != DMA_TO_DEVICE &&
463 	     scmnd->sc_data_direction != DMA_FROM_DEVICE))
464 		return;
465 
466 	if (req->fmr) {
467 		ib_fmr_pool_unmap(req->fmr);
468 		req->fmr = NULL;
469 	}
470 
471 	/*
472 	 * This handling of non-SG commands can be killed when the
473 	 * SCSI midlayer no longer generates non-SG commands.
474 	 */
475 	if (likely(scmnd->use_sg)) {
476 		nents = scmnd->use_sg;
477 		scat  = scmnd->request_buffer;
478 	} else {
479 		nents = 1;
480 		scat  = &req->fake_sg;
481 	}
482 
483 	ib_dma_unmap_sg(target->srp_host->dev->dev, scat, nents,
484 			scmnd->sc_data_direction);
485 }
486 
487 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
488 {
489 	srp_unmap_data(req->scmnd, target, req);
490 	list_move_tail(&req->list, &target->free_reqs);
491 }
492 
493 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
494 {
495 	req->scmnd->result = DID_RESET << 16;
496 	req->scmnd->scsi_done(req->scmnd);
497 	srp_remove_req(target, req);
498 }
499 
500 static int srp_reconnect_target(struct srp_target_port *target)
501 {
502 	struct ib_cm_id *new_cm_id;
503 	struct ib_qp_attr qp_attr;
504 	struct srp_request *req, *tmp;
505 	struct ib_wc wc;
506 	int ret;
507 
508 	spin_lock_irq(target->scsi_host->host_lock);
509 	if (target->state != SRP_TARGET_LIVE) {
510 		spin_unlock_irq(target->scsi_host->host_lock);
511 		return -EAGAIN;
512 	}
513 	target->state = SRP_TARGET_CONNECTING;
514 	spin_unlock_irq(target->scsi_host->host_lock);
515 
516 	srp_disconnect_target(target);
517 	/*
518 	 * Now get a new local CM ID so that we avoid confusing the
519 	 * target in case things are really fouled up.
520 	 */
521 	new_cm_id = ib_create_cm_id(target->srp_host->dev->dev,
522 				    srp_cm_handler, target);
523 	if (IS_ERR(new_cm_id)) {
524 		ret = PTR_ERR(new_cm_id);
525 		goto err;
526 	}
527 	ib_destroy_cm_id(target->cm_id);
528 	target->cm_id = new_cm_id;
529 
530 	qp_attr.qp_state = IB_QPS_RESET;
531 	ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
532 	if (ret)
533 		goto err;
534 
535 	ret = srp_init_qp(target, target->qp);
536 	if (ret)
537 		goto err;
538 
539 	while (ib_poll_cq(target->cq, 1, &wc) > 0)
540 		; /* nothing */
541 
542 	spin_lock_irq(target->scsi_host->host_lock);
543 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
544 		srp_reset_req(target, req);
545 	spin_unlock_irq(target->scsi_host->host_lock);
546 
547 	target->rx_head	 = 0;
548 	target->tx_head	 = 0;
549 	target->tx_tail  = 0;
550 
551 	target->qp_in_error = 0;
552 	ret = srp_connect_target(target);
553 	if (ret)
554 		goto err;
555 
556 	spin_lock_irq(target->scsi_host->host_lock);
557 	if (target->state == SRP_TARGET_CONNECTING) {
558 		ret = 0;
559 		target->state = SRP_TARGET_LIVE;
560 	} else
561 		ret = -EAGAIN;
562 	spin_unlock_irq(target->scsi_host->host_lock);
563 
564 	return ret;
565 
566 err:
567 	printk(KERN_ERR PFX "reconnect failed (%d), removing target port.\n", ret);
568 
569 	/*
570 	 * We couldn't reconnect, so kill our target port off.
571 	 * However, we have to defer the real removal because we might
572 	 * be in the context of the SCSI error handler now, which
573 	 * would deadlock if we call scsi_remove_host().
574 	 */
575 	spin_lock_irq(target->scsi_host->host_lock);
576 	if (target->state == SRP_TARGET_CONNECTING) {
577 		target->state = SRP_TARGET_DEAD;
578 		INIT_WORK(&target->work, srp_remove_work);
579 		schedule_work(&target->work);
580 	}
581 	spin_unlock_irq(target->scsi_host->host_lock);
582 
583 	return ret;
584 }
585 
586 static int srp_map_fmr(struct srp_target_port *target, struct scatterlist *scat,
587 		       int sg_cnt, struct srp_request *req,
588 		       struct srp_direct_buf *buf)
589 {
590 	u64 io_addr = 0;
591 	u64 *dma_pages;
592 	u32 len;
593 	int page_cnt;
594 	int i, j;
595 	int ret;
596 	struct srp_device *dev = target->srp_host->dev;
597 	struct ib_device *ibdev = dev->dev;
598 
599 	if (!dev->fmr_pool)
600 		return -ENODEV;
601 
602 	if ((ib_sg_dma_address(ibdev, &scat[0]) & ~dev->fmr_page_mask) &&
603 	    mellanox_workarounds && !memcmp(&target->ioc_guid, mellanox_oui, 3))
604 		return -EINVAL;
605 
606 	len = page_cnt = 0;
607 	for (i = 0; i < sg_cnt; ++i) {
608 		unsigned int dma_len = ib_sg_dma_len(ibdev, &scat[i]);
609 
610 		if (ib_sg_dma_address(ibdev, &scat[i]) & ~dev->fmr_page_mask) {
611 			if (i > 0)
612 				return -EINVAL;
613 			else
614 				++page_cnt;
615 		}
616 		if ((ib_sg_dma_address(ibdev, &scat[i]) + dma_len) &
617 		    ~dev->fmr_page_mask) {
618 			if (i < sg_cnt - 1)
619 				return -EINVAL;
620 			else
621 				++page_cnt;
622 		}
623 
624 		len += dma_len;
625 	}
626 
627 	page_cnt += len >> dev->fmr_page_shift;
628 	if (page_cnt > SRP_FMR_SIZE)
629 		return -ENOMEM;
630 
631 	dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
632 	if (!dma_pages)
633 		return -ENOMEM;
634 
635 	page_cnt = 0;
636 	for (i = 0; i < sg_cnt; ++i) {
637 		unsigned int dma_len = ib_sg_dma_len(ibdev, &scat[i]);
638 
639 		for (j = 0; j < dma_len; j += dev->fmr_page_size)
640 			dma_pages[page_cnt++] =
641 				(ib_sg_dma_address(ibdev, &scat[i]) &
642 				 dev->fmr_page_mask) + j;
643 	}
644 
645 	req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
646 					dma_pages, page_cnt, io_addr);
647 	if (IS_ERR(req->fmr)) {
648 		ret = PTR_ERR(req->fmr);
649 		req->fmr = NULL;
650 		goto out;
651 	}
652 
653 	buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, &scat[0]) &
654 			       ~dev->fmr_page_mask);
655 	buf->key = cpu_to_be32(req->fmr->fmr->rkey);
656 	buf->len = cpu_to_be32(len);
657 
658 	ret = 0;
659 
660 out:
661 	kfree(dma_pages);
662 
663 	return ret;
664 }
665 
666 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
667 			struct srp_request *req)
668 {
669 	struct scatterlist *scat;
670 	struct srp_cmd *cmd = req->cmd->buf;
671 	int len, nents, count;
672 	u8 fmt = SRP_DATA_DESC_DIRECT;
673 	struct srp_device *dev;
674 	struct ib_device *ibdev;
675 
676 	if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
677 		return sizeof (struct srp_cmd);
678 
679 	if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
680 	    scmnd->sc_data_direction != DMA_TO_DEVICE) {
681 		printk(KERN_WARNING PFX "Unhandled data direction %d\n",
682 		       scmnd->sc_data_direction);
683 		return -EINVAL;
684 	}
685 
686 	/*
687 	 * This handling of non-SG commands can be killed when the
688 	 * SCSI midlayer no longer generates non-SG commands.
689 	 */
690 	if (likely(scmnd->use_sg)) {
691 		nents = scmnd->use_sg;
692 		scat  = scmnd->request_buffer;
693 	} else {
694 		nents = 1;
695 		scat  = &req->fake_sg;
696 		sg_init_one(scat, scmnd->request_buffer, scmnd->request_bufflen);
697 	}
698 
699 	dev = target->srp_host->dev;
700 	ibdev = dev->dev;
701 
702 	count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
703 
704 	fmt = SRP_DATA_DESC_DIRECT;
705 	len = sizeof (struct srp_cmd) +	sizeof (struct srp_direct_buf);
706 
707 	if (count == 1) {
708 		/*
709 		 * The midlayer only generated a single gather/scatter
710 		 * entry, or DMA mapping coalesced everything to a
711 		 * single entry.  So a direct descriptor along with
712 		 * the DMA MR suffices.
713 		 */
714 		struct srp_direct_buf *buf = (void *) cmd->add_data;
715 
716 		buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
717 		buf->key = cpu_to_be32(dev->mr->rkey);
718 		buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
719 	} else if (srp_map_fmr(target, scat, count, req,
720 			       (void *) cmd->add_data)) {
721 		/*
722 		 * FMR mapping failed, and the scatterlist has more
723 		 * than one entry.  Generate an indirect memory
724 		 * descriptor.
725 		 */
726 		struct srp_indirect_buf *buf = (void *) cmd->add_data;
727 		u32 datalen = 0;
728 		int i;
729 
730 		fmt = SRP_DATA_DESC_INDIRECT;
731 		len = sizeof (struct srp_cmd) +
732 			sizeof (struct srp_indirect_buf) +
733 			count * sizeof (struct srp_direct_buf);
734 
735 		for (i = 0; i < count; ++i) {
736 			unsigned int dma_len = ib_sg_dma_len(ibdev, &scat[i]);
737 
738 			buf->desc_list[i].va  =
739 				cpu_to_be64(ib_sg_dma_address(ibdev, &scat[i]));
740 			buf->desc_list[i].key =
741 				cpu_to_be32(dev->mr->rkey);
742 			buf->desc_list[i].len = cpu_to_be32(dma_len);
743 			datalen += dma_len;
744 		}
745 
746 		if (scmnd->sc_data_direction == DMA_TO_DEVICE)
747 			cmd->data_out_desc_cnt = count;
748 		else
749 			cmd->data_in_desc_cnt = count;
750 
751 		buf->table_desc.va  =
752 			cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
753 		buf->table_desc.key =
754 			cpu_to_be32(target->srp_host->dev->mr->rkey);
755 		buf->table_desc.len =
756 			cpu_to_be32(count * sizeof (struct srp_direct_buf));
757 
758 		buf->len = cpu_to_be32(datalen);
759 	}
760 
761 	if (scmnd->sc_data_direction == DMA_TO_DEVICE)
762 		cmd->buf_fmt = fmt << 4;
763 	else
764 		cmd->buf_fmt = fmt;
765 
766 	return len;
767 }
768 
769 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
770 {
771 	struct srp_request *req;
772 	struct scsi_cmnd *scmnd;
773 	unsigned long flags;
774 	s32 delta;
775 
776 	delta = (s32) be32_to_cpu(rsp->req_lim_delta);
777 
778 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
779 
780 	target->req_lim += delta;
781 
782 	req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
783 
784 	if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
785 		if (be32_to_cpu(rsp->resp_data_len) < 4)
786 			req->tsk_status = -1;
787 		else
788 			req->tsk_status = rsp->data[3];
789 		complete(&req->done);
790 	} else {
791 		scmnd = req->scmnd;
792 		if (!scmnd)
793 			printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
794 			       (unsigned long long) rsp->tag);
795 		scmnd->result = rsp->status;
796 
797 		if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
798 			memcpy(scmnd->sense_buffer, rsp->data +
799 			       be32_to_cpu(rsp->resp_data_len),
800 			       min_t(int, be32_to_cpu(rsp->sense_data_len),
801 				     SCSI_SENSE_BUFFERSIZE));
802 		}
803 
804 		if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
805 			scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
806 		else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
807 			scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
808 
809 		if (!req->tsk_mgmt) {
810 			scmnd->host_scribble = (void *) -1L;
811 			scmnd->scsi_done(scmnd);
812 
813 			srp_remove_req(target, req);
814 		} else
815 			req->cmd_done = 1;
816 	}
817 
818 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
819 }
820 
821 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
822 {
823 	struct ib_device *dev;
824 	struct srp_iu *iu;
825 	u8 opcode;
826 
827 	iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
828 
829 	dev = target->srp_host->dev->dev;
830 	ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
831 				   DMA_FROM_DEVICE);
832 
833 	opcode = *(u8 *) iu->buf;
834 
835 	if (0) {
836 		int i;
837 
838 		printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
839 
840 		for (i = 0; i < wc->byte_len; ++i) {
841 			if (i % 8 == 0)
842 				printk(KERN_ERR "  [%02x] ", i);
843 			printk(" %02x", ((u8 *) iu->buf)[i]);
844 			if ((i + 1) % 8 == 0)
845 				printk("\n");
846 		}
847 
848 		if (wc->byte_len % 8)
849 			printk("\n");
850 	}
851 
852 	switch (opcode) {
853 	case SRP_RSP:
854 		srp_process_rsp(target, iu->buf);
855 		break;
856 
857 	case SRP_T_LOGOUT:
858 		/* XXX Handle target logout */
859 		printk(KERN_WARNING PFX "Got target logout request\n");
860 		break;
861 
862 	default:
863 		printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
864 		break;
865 	}
866 
867 	ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
868 				      DMA_FROM_DEVICE);
869 }
870 
871 static void srp_completion(struct ib_cq *cq, void *target_ptr)
872 {
873 	struct srp_target_port *target = target_ptr;
874 	struct ib_wc wc;
875 
876 	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
877 	while (ib_poll_cq(cq, 1, &wc) > 0) {
878 		if (wc.status) {
879 			printk(KERN_ERR PFX "failed %s status %d\n",
880 			       wc.wr_id & SRP_OP_RECV ? "receive" : "send",
881 			       wc.status);
882 			target->qp_in_error = 1;
883 			break;
884 		}
885 
886 		if (wc.wr_id & SRP_OP_RECV)
887 			srp_handle_recv(target, &wc);
888 		else
889 			++target->tx_tail;
890 	}
891 }
892 
893 static int __srp_post_recv(struct srp_target_port *target)
894 {
895 	struct srp_iu *iu;
896 	struct ib_sge list;
897 	struct ib_recv_wr wr, *bad_wr;
898 	unsigned int next;
899 	int ret;
900 
901 	next 	 = target->rx_head & (SRP_RQ_SIZE - 1);
902 	wr.wr_id = next | SRP_OP_RECV;
903 	iu 	 = target->rx_ring[next];
904 
905 	list.addr   = iu->dma;
906 	list.length = iu->size;
907 	list.lkey   = target->srp_host->dev->mr->lkey;
908 
909 	wr.next     = NULL;
910 	wr.sg_list  = &list;
911 	wr.num_sge  = 1;
912 
913 	ret = ib_post_recv(target->qp, &wr, &bad_wr);
914 	if (!ret)
915 		++target->rx_head;
916 
917 	return ret;
918 }
919 
920 static int srp_post_recv(struct srp_target_port *target)
921 {
922 	unsigned long flags;
923 	int ret;
924 
925 	spin_lock_irqsave(target->scsi_host->host_lock, flags);
926 	ret = __srp_post_recv(target);
927 	spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
928 
929 	return ret;
930 }
931 
932 /*
933  * Must be called with target->scsi_host->host_lock held to protect
934  * req_lim and tx_head.  Lock cannot be dropped between call here and
935  * call to __srp_post_send().
936  */
937 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
938 {
939 	if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
940 		return NULL;
941 
942 	if (unlikely(target->req_lim < 1))
943 		++target->zero_req_lim;
944 
945 	return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
946 }
947 
948 /*
949  * Must be called with target->scsi_host->host_lock held to protect
950  * req_lim and tx_head.
951  */
952 static int __srp_post_send(struct srp_target_port *target,
953 			   struct srp_iu *iu, int len)
954 {
955 	struct ib_sge list;
956 	struct ib_send_wr wr, *bad_wr;
957 	int ret = 0;
958 
959 	list.addr   = iu->dma;
960 	list.length = len;
961 	list.lkey   = target->srp_host->dev->mr->lkey;
962 
963 	wr.next       = NULL;
964 	wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
965 	wr.sg_list    = &list;
966 	wr.num_sge    = 1;
967 	wr.opcode     = IB_WR_SEND;
968 	wr.send_flags = IB_SEND_SIGNALED;
969 
970 	ret = ib_post_send(target->qp, &wr, &bad_wr);
971 
972 	if (!ret) {
973 		++target->tx_head;
974 		--target->req_lim;
975 	}
976 
977 	return ret;
978 }
979 
980 static int srp_queuecommand(struct scsi_cmnd *scmnd,
981 			    void (*done)(struct scsi_cmnd *))
982 {
983 	struct srp_target_port *target = host_to_target(scmnd->device->host);
984 	struct srp_request *req;
985 	struct srp_iu *iu;
986 	struct srp_cmd *cmd;
987 	struct ib_device *dev;
988 	int len;
989 
990 	if (target->state == SRP_TARGET_CONNECTING)
991 		goto err;
992 
993 	if (target->state == SRP_TARGET_DEAD ||
994 	    target->state == SRP_TARGET_REMOVED) {
995 		scmnd->result = DID_BAD_TARGET << 16;
996 		done(scmnd);
997 		return 0;
998 	}
999 
1000 	iu = __srp_get_tx_iu(target);
1001 	if (!iu)
1002 		goto err;
1003 
1004 	dev = target->srp_host->dev->dev;
1005 	ib_dma_sync_single_for_cpu(dev, iu->dma, srp_max_iu_len,
1006 				   DMA_TO_DEVICE);
1007 
1008 	req = list_entry(target->free_reqs.next, struct srp_request, list);
1009 
1010 	scmnd->scsi_done     = done;
1011 	scmnd->result        = 0;
1012 	scmnd->host_scribble = (void *) (long) req->index;
1013 
1014 	cmd = iu->buf;
1015 	memset(cmd, 0, sizeof *cmd);
1016 
1017 	cmd->opcode = SRP_CMD;
1018 	cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1019 	cmd->tag    = req->index;
1020 	memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1021 
1022 	req->scmnd    = scmnd;
1023 	req->cmd      = iu;
1024 	req->cmd_done = 0;
1025 	req->tsk_mgmt = NULL;
1026 
1027 	len = srp_map_data(scmnd, target, req);
1028 	if (len < 0) {
1029 		printk(KERN_ERR PFX "Failed to map data\n");
1030 		goto err;
1031 	}
1032 
1033 	if (__srp_post_recv(target)) {
1034 		printk(KERN_ERR PFX "Recv failed\n");
1035 		goto err_unmap;
1036 	}
1037 
1038 	ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
1039 				      DMA_TO_DEVICE);
1040 
1041 	if (__srp_post_send(target, iu, len)) {
1042 		printk(KERN_ERR PFX "Send failed\n");
1043 		goto err_unmap;
1044 	}
1045 
1046 	list_move_tail(&req->list, &target->req_queue);
1047 
1048 	return 0;
1049 
1050 err_unmap:
1051 	srp_unmap_data(scmnd, target, req);
1052 
1053 err:
1054 	return SCSI_MLQUEUE_HOST_BUSY;
1055 }
1056 
1057 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1058 {
1059 	int i;
1060 
1061 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1062 		target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1063 						  target->max_ti_iu_len,
1064 						  GFP_KERNEL, DMA_FROM_DEVICE);
1065 		if (!target->rx_ring[i])
1066 			goto err;
1067 	}
1068 
1069 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1070 		target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1071 						  srp_max_iu_len,
1072 						  GFP_KERNEL, DMA_TO_DEVICE);
1073 		if (!target->tx_ring[i])
1074 			goto err;
1075 	}
1076 
1077 	return 0;
1078 
1079 err:
1080 	for (i = 0; i < SRP_RQ_SIZE; ++i) {
1081 		srp_free_iu(target->srp_host, target->rx_ring[i]);
1082 		target->rx_ring[i] = NULL;
1083 	}
1084 
1085 	for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
1086 		srp_free_iu(target->srp_host, target->tx_ring[i]);
1087 		target->tx_ring[i] = NULL;
1088 	}
1089 
1090 	return -ENOMEM;
1091 }
1092 
1093 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1094 			       struct ib_cm_event *event,
1095 			       struct srp_target_port *target)
1096 {
1097 	struct ib_class_port_info *cpi;
1098 	int opcode;
1099 
1100 	switch (event->param.rej_rcvd.reason) {
1101 	case IB_CM_REJ_PORT_CM_REDIRECT:
1102 		cpi = event->param.rej_rcvd.ari;
1103 		target->path.dlid = cpi->redirect_lid;
1104 		target->path.pkey = cpi->redirect_pkey;
1105 		cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1106 		memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1107 
1108 		target->status = target->path.dlid ?
1109 			SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1110 		break;
1111 
1112 	case IB_CM_REJ_PORT_REDIRECT:
1113 		if (topspin_workarounds &&
1114 		    !memcmp(&target->ioc_guid, topspin_oui, 3)) {
1115 			/*
1116 			 * Topspin/Cisco SRP gateways incorrectly send
1117 			 * reject reason code 25 when they mean 24
1118 			 * (port redirect).
1119 			 */
1120 			memcpy(target->path.dgid.raw,
1121 			       event->param.rej_rcvd.ari, 16);
1122 
1123 			printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1124 			       (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1125 			       (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1126 
1127 			target->status = SRP_PORT_REDIRECT;
1128 		} else {
1129 			printk(KERN_WARNING "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1130 			target->status = -ECONNRESET;
1131 		}
1132 		break;
1133 
1134 	case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1135 		printk(KERN_WARNING "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1136 		target->status = -ECONNRESET;
1137 		break;
1138 
1139 	case IB_CM_REJ_CONSUMER_DEFINED:
1140 		opcode = *(u8 *) event->private_data;
1141 		if (opcode == SRP_LOGIN_REJ) {
1142 			struct srp_login_rej *rej = event->private_data;
1143 			u32 reason = be32_to_cpu(rej->reason);
1144 
1145 			if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1146 				printk(KERN_WARNING PFX
1147 				       "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1148 			else
1149 				printk(KERN_WARNING PFX
1150 				       "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1151 		} else
1152 			printk(KERN_WARNING "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1153 			       " opcode 0x%02x\n", opcode);
1154 		target->status = -ECONNRESET;
1155 		break;
1156 
1157 	default:
1158 		printk(KERN_WARNING "  REJ reason 0x%x\n",
1159 		       event->param.rej_rcvd.reason);
1160 		target->status = -ECONNRESET;
1161 	}
1162 }
1163 
1164 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1165 {
1166 	struct srp_target_port *target = cm_id->context;
1167 	struct ib_qp_attr *qp_attr = NULL;
1168 	int attr_mask = 0;
1169 	int comp = 0;
1170 	int opcode = 0;
1171 
1172 	switch (event->event) {
1173 	case IB_CM_REQ_ERROR:
1174 		printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
1175 		comp = 1;
1176 		target->status = -ECONNRESET;
1177 		break;
1178 
1179 	case IB_CM_REP_RECEIVED:
1180 		comp = 1;
1181 		opcode = *(u8 *) event->private_data;
1182 
1183 		if (opcode == SRP_LOGIN_RSP) {
1184 			struct srp_login_rsp *rsp = event->private_data;
1185 
1186 			target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1187 			target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1188 
1189 			target->scsi_host->can_queue = min(target->req_lim,
1190 							   target->scsi_host->can_queue);
1191 		} else {
1192 			printk(KERN_WARNING PFX "Unhandled RSP opcode %#x\n", opcode);
1193 			target->status = -ECONNRESET;
1194 			break;
1195 		}
1196 
1197 		if (!target->rx_ring[0]) {
1198 			target->status = srp_alloc_iu_bufs(target);
1199 			if (target->status)
1200 				break;
1201 		}
1202 
1203 		qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1204 		if (!qp_attr) {
1205 			target->status = -ENOMEM;
1206 			break;
1207 		}
1208 
1209 		qp_attr->qp_state = IB_QPS_RTR;
1210 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1211 		if (target->status)
1212 			break;
1213 
1214 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1215 		if (target->status)
1216 			break;
1217 
1218 		target->status = srp_post_recv(target);
1219 		if (target->status)
1220 			break;
1221 
1222 		qp_attr->qp_state = IB_QPS_RTS;
1223 		target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1224 		if (target->status)
1225 			break;
1226 
1227 		target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1228 		if (target->status)
1229 			break;
1230 
1231 		target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1232 		if (target->status)
1233 			break;
1234 
1235 		break;
1236 
1237 	case IB_CM_REJ_RECEIVED:
1238 		printk(KERN_DEBUG PFX "REJ received\n");
1239 		comp = 1;
1240 
1241 		srp_cm_rej_handler(cm_id, event, target);
1242 		break;
1243 
1244 	case IB_CM_DREQ_RECEIVED:
1245 		printk(KERN_WARNING PFX "DREQ received - connection closed\n");
1246 		if (ib_send_cm_drep(cm_id, NULL, 0))
1247 			printk(KERN_ERR PFX "Sending CM DREP failed\n");
1248 		break;
1249 
1250 	case IB_CM_TIMEWAIT_EXIT:
1251 		printk(KERN_ERR PFX "connection closed\n");
1252 
1253 		comp = 1;
1254 		target->status = 0;
1255 		break;
1256 
1257 	case IB_CM_MRA_RECEIVED:
1258 	case IB_CM_DREQ_ERROR:
1259 	case IB_CM_DREP_RECEIVED:
1260 		break;
1261 
1262 	default:
1263 		printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
1264 		break;
1265 	}
1266 
1267 	if (comp)
1268 		complete(&target->done);
1269 
1270 	kfree(qp_attr);
1271 
1272 	return 0;
1273 }
1274 
1275 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1276 			     struct srp_request *req, u8 func)
1277 {
1278 	struct srp_iu *iu;
1279 	struct srp_tsk_mgmt *tsk_mgmt;
1280 
1281 	spin_lock_irq(target->scsi_host->host_lock);
1282 
1283 	if (target->state == SRP_TARGET_DEAD ||
1284 	    target->state == SRP_TARGET_REMOVED) {
1285 		req->scmnd->result = DID_BAD_TARGET << 16;
1286 		goto out;
1287 	}
1288 
1289 	init_completion(&req->done);
1290 
1291 	iu = __srp_get_tx_iu(target);
1292 	if (!iu)
1293 		goto out;
1294 
1295 	tsk_mgmt = iu->buf;
1296 	memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1297 
1298 	tsk_mgmt->opcode 	= SRP_TSK_MGMT;
1299 	tsk_mgmt->lun 		= cpu_to_be64((u64) req->scmnd->device->lun << 48);
1300 	tsk_mgmt->tag 		= req->index | SRP_TAG_TSK_MGMT;
1301 	tsk_mgmt->tsk_mgmt_func = func;
1302 	tsk_mgmt->task_tag 	= req->index;
1303 
1304 	if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1305 		goto out;
1306 
1307 	req->tsk_mgmt = iu;
1308 
1309 	spin_unlock_irq(target->scsi_host->host_lock);
1310 
1311 	if (!wait_for_completion_timeout(&req->done,
1312 					 msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1313 		return -1;
1314 
1315 	return 0;
1316 
1317 out:
1318 	spin_unlock_irq(target->scsi_host->host_lock);
1319 	return -1;
1320 }
1321 
1322 static int srp_find_req(struct srp_target_port *target,
1323 			struct scsi_cmnd *scmnd,
1324 			struct srp_request **req)
1325 {
1326 	if (scmnd->host_scribble == (void *) -1L)
1327 		return -1;
1328 
1329 	*req = &target->req_ring[(long) scmnd->host_scribble];
1330 
1331 	return 0;
1332 }
1333 
1334 static int srp_abort(struct scsi_cmnd *scmnd)
1335 {
1336 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1337 	struct srp_request *req;
1338 	int ret = SUCCESS;
1339 
1340 	printk(KERN_ERR "SRP abort called\n");
1341 
1342 	if (target->qp_in_error)
1343 		return FAILED;
1344 	if (srp_find_req(target, scmnd, &req))
1345 		return FAILED;
1346 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
1347 		return FAILED;
1348 
1349 	spin_lock_irq(target->scsi_host->host_lock);
1350 
1351 	if (req->cmd_done) {
1352 		srp_remove_req(target, req);
1353 		scmnd->scsi_done(scmnd);
1354 	} else if (!req->tsk_status) {
1355 		srp_remove_req(target, req);
1356 		scmnd->result = DID_ABORT << 16;
1357 	} else
1358 		ret = FAILED;
1359 
1360 	spin_unlock_irq(target->scsi_host->host_lock);
1361 
1362 	return ret;
1363 }
1364 
1365 static int srp_reset_device(struct scsi_cmnd *scmnd)
1366 {
1367 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1368 	struct srp_request *req, *tmp;
1369 
1370 	printk(KERN_ERR "SRP reset_device called\n");
1371 
1372 	if (target->qp_in_error)
1373 		return FAILED;
1374 	if (srp_find_req(target, scmnd, &req))
1375 		return FAILED;
1376 	if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
1377 		return FAILED;
1378 	if (req->tsk_status)
1379 		return FAILED;
1380 
1381 	spin_lock_irq(target->scsi_host->host_lock);
1382 
1383 	list_for_each_entry_safe(req, tmp, &target->req_queue, list)
1384 		if (req->scmnd->device == scmnd->device)
1385 			srp_reset_req(target, req);
1386 
1387 	spin_unlock_irq(target->scsi_host->host_lock);
1388 
1389 	return SUCCESS;
1390 }
1391 
1392 static int srp_reset_host(struct scsi_cmnd *scmnd)
1393 {
1394 	struct srp_target_port *target = host_to_target(scmnd->device->host);
1395 	int ret = FAILED;
1396 
1397 	printk(KERN_ERR PFX "SRP reset_host called\n");
1398 
1399 	if (!srp_reconnect_target(target))
1400 		ret = SUCCESS;
1401 
1402 	return ret;
1403 }
1404 
1405 static ssize_t show_id_ext(struct class_device *cdev, char *buf)
1406 {
1407 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1408 
1409 	if (target->state == SRP_TARGET_DEAD ||
1410 	    target->state == SRP_TARGET_REMOVED)
1411 		return -ENODEV;
1412 
1413 	return sprintf(buf, "0x%016llx\n",
1414 		       (unsigned long long) be64_to_cpu(target->id_ext));
1415 }
1416 
1417 static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
1418 {
1419 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1420 
1421 	if (target->state == SRP_TARGET_DEAD ||
1422 	    target->state == SRP_TARGET_REMOVED)
1423 		return -ENODEV;
1424 
1425 	return sprintf(buf, "0x%016llx\n",
1426 		       (unsigned long long) be64_to_cpu(target->ioc_guid));
1427 }
1428 
1429 static ssize_t show_service_id(struct class_device *cdev, char *buf)
1430 {
1431 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1432 
1433 	if (target->state == SRP_TARGET_DEAD ||
1434 	    target->state == SRP_TARGET_REMOVED)
1435 		return -ENODEV;
1436 
1437 	return sprintf(buf, "0x%016llx\n",
1438 		       (unsigned long long) be64_to_cpu(target->service_id));
1439 }
1440 
1441 static ssize_t show_pkey(struct class_device *cdev, char *buf)
1442 {
1443 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1444 
1445 	if (target->state == SRP_TARGET_DEAD ||
1446 	    target->state == SRP_TARGET_REMOVED)
1447 		return -ENODEV;
1448 
1449 	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1450 }
1451 
1452 static ssize_t show_dgid(struct class_device *cdev, char *buf)
1453 {
1454 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1455 
1456 	if (target->state == SRP_TARGET_DEAD ||
1457 	    target->state == SRP_TARGET_REMOVED)
1458 		return -ENODEV;
1459 
1460 	return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1461 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
1462 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
1463 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
1464 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
1465 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
1466 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
1467 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
1468 		       be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
1469 }
1470 
1471 static ssize_t show_orig_dgid(struct class_device *cdev, char *buf)
1472 {
1473 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1474 
1475 	if (target->state == SRP_TARGET_DEAD ||
1476 	    target->state == SRP_TARGET_REMOVED)
1477 		return -ENODEV;
1478 
1479 	return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1480 		       be16_to_cpu(target->orig_dgid[0]),
1481 		       be16_to_cpu(target->orig_dgid[1]),
1482 		       be16_to_cpu(target->orig_dgid[2]),
1483 		       be16_to_cpu(target->orig_dgid[3]),
1484 		       be16_to_cpu(target->orig_dgid[4]),
1485 		       be16_to_cpu(target->orig_dgid[5]),
1486 		       be16_to_cpu(target->orig_dgid[6]),
1487 		       be16_to_cpu(target->orig_dgid[7]));
1488 }
1489 
1490 static ssize_t show_zero_req_lim(struct class_device *cdev, char *buf)
1491 {
1492 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1493 
1494 	if (target->state == SRP_TARGET_DEAD ||
1495 	    target->state == SRP_TARGET_REMOVED)
1496 		return -ENODEV;
1497 
1498 	return sprintf(buf, "%d\n", target->zero_req_lim);
1499 }
1500 
1501 static ssize_t show_local_ib_port(struct class_device *cdev, char *buf)
1502 {
1503 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1504 
1505 	return sprintf(buf, "%d\n", target->srp_host->port);
1506 }
1507 
1508 static ssize_t show_local_ib_device(struct class_device *cdev, char *buf)
1509 {
1510 	struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1511 
1512 	return sprintf(buf, "%s\n", target->srp_host->dev->dev->name);
1513 }
1514 
1515 static CLASS_DEVICE_ATTR(id_ext,	  S_IRUGO, show_id_ext,		 NULL);
1516 static CLASS_DEVICE_ATTR(ioc_guid,	  S_IRUGO, show_ioc_guid,	 NULL);
1517 static CLASS_DEVICE_ATTR(service_id,	  S_IRUGO, show_service_id,	 NULL);
1518 static CLASS_DEVICE_ATTR(pkey,		  S_IRUGO, show_pkey,		 NULL);
1519 static CLASS_DEVICE_ATTR(dgid,		  S_IRUGO, show_dgid,		 NULL);
1520 static CLASS_DEVICE_ATTR(orig_dgid,	  S_IRUGO, show_orig_dgid,	 NULL);
1521 static CLASS_DEVICE_ATTR(zero_req_lim,	  S_IRUGO, show_zero_req_lim,	 NULL);
1522 static CLASS_DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,	 NULL);
1523 static CLASS_DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1524 
1525 static struct class_device_attribute *srp_host_attrs[] = {
1526 	&class_device_attr_id_ext,
1527 	&class_device_attr_ioc_guid,
1528 	&class_device_attr_service_id,
1529 	&class_device_attr_pkey,
1530 	&class_device_attr_dgid,
1531 	&class_device_attr_orig_dgid,
1532 	&class_device_attr_zero_req_lim,
1533 	&class_device_attr_local_ib_port,
1534 	&class_device_attr_local_ib_device,
1535 	NULL
1536 };
1537 
1538 static struct scsi_host_template srp_template = {
1539 	.module				= THIS_MODULE,
1540 	.name				= "InfiniBand SRP initiator",
1541 	.proc_name			= DRV_NAME,
1542 	.info				= srp_target_info,
1543 	.queuecommand			= srp_queuecommand,
1544 	.eh_abort_handler		= srp_abort,
1545 	.eh_device_reset_handler	= srp_reset_device,
1546 	.eh_host_reset_handler		= srp_reset_host,
1547 	.can_queue			= SRP_SQ_SIZE,
1548 	.this_id			= -1,
1549 	.cmd_per_lun			= SRP_SQ_SIZE,
1550 	.use_clustering			= ENABLE_CLUSTERING,
1551 	.shost_attrs			= srp_host_attrs
1552 };
1553 
1554 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1555 {
1556 	sprintf(target->target_name, "SRP.T10:%016llX",
1557 		 (unsigned long long) be64_to_cpu(target->id_ext));
1558 
1559 	if (scsi_add_host(target->scsi_host, host->dev->dev->dma_device))
1560 		return -ENODEV;
1561 
1562 	spin_lock(&host->target_lock);
1563 	list_add_tail(&target->list, &host->target_list);
1564 	spin_unlock(&host->target_lock);
1565 
1566 	target->state = SRP_TARGET_LIVE;
1567 
1568 	scsi_scan_target(&target->scsi_host->shost_gendev,
1569 			 0, target->scsi_id, SCAN_WILD_CARD, 0);
1570 
1571 	return 0;
1572 }
1573 
1574 static void srp_release_class_dev(struct class_device *class_dev)
1575 {
1576 	struct srp_host *host =
1577 		container_of(class_dev, struct srp_host, class_dev);
1578 
1579 	complete(&host->released);
1580 }
1581 
1582 static struct class srp_class = {
1583 	.name    = "infiniband_srp",
1584 	.release = srp_release_class_dev
1585 };
1586 
1587 /*
1588  * Target ports are added by writing
1589  *
1590  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1591  *     pkey=<P_Key>,service_id=<service ID>
1592  *
1593  * to the add_target sysfs attribute.
1594  */
1595 enum {
1596 	SRP_OPT_ERR		= 0,
1597 	SRP_OPT_ID_EXT		= 1 << 0,
1598 	SRP_OPT_IOC_GUID	= 1 << 1,
1599 	SRP_OPT_DGID		= 1 << 2,
1600 	SRP_OPT_PKEY		= 1 << 3,
1601 	SRP_OPT_SERVICE_ID	= 1 << 4,
1602 	SRP_OPT_MAX_SECT	= 1 << 5,
1603 	SRP_OPT_MAX_CMD_PER_LUN	= 1 << 6,
1604 	SRP_OPT_IO_CLASS	= 1 << 7,
1605 	SRP_OPT_INITIATOR_EXT	= 1 << 8,
1606 	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
1607 				   SRP_OPT_IOC_GUID	|
1608 				   SRP_OPT_DGID		|
1609 				   SRP_OPT_PKEY		|
1610 				   SRP_OPT_SERVICE_ID),
1611 };
1612 
1613 static match_table_t srp_opt_tokens = {
1614 	{ SRP_OPT_ID_EXT,		"id_ext=%s" 		},
1615 	{ SRP_OPT_IOC_GUID,		"ioc_guid=%s" 		},
1616 	{ SRP_OPT_DGID,			"dgid=%s" 		},
1617 	{ SRP_OPT_PKEY,			"pkey=%x" 		},
1618 	{ SRP_OPT_SERVICE_ID,		"service_id=%s"		},
1619 	{ SRP_OPT_MAX_SECT,		"max_sect=%d" 		},
1620 	{ SRP_OPT_MAX_CMD_PER_LUN,	"max_cmd_per_lun=%d" 	},
1621 	{ SRP_OPT_IO_CLASS,		"io_class=%x"		},
1622 	{ SRP_OPT_INITIATOR_EXT,	"initiator_ext=%s"	},
1623 	{ SRP_OPT_ERR,			NULL 			}
1624 };
1625 
1626 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1627 {
1628 	char *options, *sep_opt;
1629 	char *p;
1630 	char dgid[3];
1631 	substring_t args[MAX_OPT_ARGS];
1632 	int opt_mask = 0;
1633 	int token;
1634 	int ret = -EINVAL;
1635 	int i;
1636 
1637 	options = kstrdup(buf, GFP_KERNEL);
1638 	if (!options)
1639 		return -ENOMEM;
1640 
1641 	sep_opt = options;
1642 	while ((p = strsep(&sep_opt, ",")) != NULL) {
1643 		if (!*p)
1644 			continue;
1645 
1646 		token = match_token(p, srp_opt_tokens, args);
1647 		opt_mask |= token;
1648 
1649 		switch (token) {
1650 		case SRP_OPT_ID_EXT:
1651 			p = match_strdup(args);
1652 			if (!p) {
1653 				ret = -ENOMEM;
1654 				goto out;
1655 			}
1656 			target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1657 			kfree(p);
1658 			break;
1659 
1660 		case SRP_OPT_IOC_GUID:
1661 			p = match_strdup(args);
1662 			if (!p) {
1663 				ret = -ENOMEM;
1664 				goto out;
1665 			}
1666 			target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1667 			kfree(p);
1668 			break;
1669 
1670 		case SRP_OPT_DGID:
1671 			p = match_strdup(args);
1672 			if (!p) {
1673 				ret = -ENOMEM;
1674 				goto out;
1675 			}
1676 			if (strlen(p) != 32) {
1677 				printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1678 				kfree(p);
1679 				goto out;
1680 			}
1681 
1682 			for (i = 0; i < 16; ++i) {
1683 				strlcpy(dgid, p + i * 2, 3);
1684 				target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1685 			}
1686 			kfree(p);
1687 			memcpy(target->orig_dgid, target->path.dgid.raw, 16);
1688 			break;
1689 
1690 		case SRP_OPT_PKEY:
1691 			if (match_hex(args, &token)) {
1692 				printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1693 				goto out;
1694 			}
1695 			target->path.pkey = cpu_to_be16(token);
1696 			break;
1697 
1698 		case SRP_OPT_SERVICE_ID:
1699 			p = match_strdup(args);
1700 			if (!p) {
1701 				ret = -ENOMEM;
1702 				goto out;
1703 			}
1704 			target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1705 			kfree(p);
1706 			break;
1707 
1708 		case SRP_OPT_MAX_SECT:
1709 			if (match_int(args, &token)) {
1710 				printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1711 				goto out;
1712 			}
1713 			target->scsi_host->max_sectors = token;
1714 			break;
1715 
1716 		case SRP_OPT_MAX_CMD_PER_LUN:
1717 			if (match_int(args, &token)) {
1718 				printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
1719 				goto out;
1720 			}
1721 			target->scsi_host->cmd_per_lun = min(token, SRP_SQ_SIZE);
1722 			break;
1723 
1724 		case SRP_OPT_IO_CLASS:
1725 			if (match_hex(args, &token)) {
1726 				printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
1727 				goto out;
1728 			}
1729 			if (token != SRP_REV10_IB_IO_CLASS &&
1730 			    token != SRP_REV16A_IB_IO_CLASS) {
1731 				printk(KERN_WARNING PFX "unknown IO class parameter value"
1732 				       " %x specified (use %x or %x).\n",
1733 				       token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
1734 				goto out;
1735 			}
1736 			target->io_class = token;
1737 			break;
1738 
1739 		case SRP_OPT_INITIATOR_EXT:
1740 			p = match_strdup(args);
1741 			if (!p) {
1742 				ret = -ENOMEM;
1743 				goto out;
1744 			}
1745 			target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1746 			kfree(p);
1747 			break;
1748 
1749 		default:
1750 			printk(KERN_WARNING PFX "unknown parameter or missing value "
1751 			       "'%s' in target creation request\n", p);
1752 			goto out;
1753 		}
1754 	}
1755 
1756 	if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1757 		ret = 0;
1758 	else
1759 		for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1760 			if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1761 			    !(srp_opt_tokens[i].token & opt_mask))
1762 				printk(KERN_WARNING PFX "target creation request is "
1763 				       "missing parameter '%s'\n",
1764 				       srp_opt_tokens[i].pattern);
1765 
1766 out:
1767 	kfree(options);
1768 	return ret;
1769 }
1770 
1771 static ssize_t srp_create_target(struct class_device *class_dev,
1772 				 const char *buf, size_t count)
1773 {
1774 	struct srp_host *host =
1775 		container_of(class_dev, struct srp_host, class_dev);
1776 	struct Scsi_Host *target_host;
1777 	struct srp_target_port *target;
1778 	int ret;
1779 	int i;
1780 
1781 	target_host = scsi_host_alloc(&srp_template,
1782 				      sizeof (struct srp_target_port));
1783 	if (!target_host)
1784 		return -ENOMEM;
1785 
1786 	target_host->max_lun     = SRP_MAX_LUN;
1787 	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
1788 
1789 	target = host_to_target(target_host);
1790 
1791 	target->io_class   = SRP_REV16A_IB_IO_CLASS;
1792 	target->scsi_host  = target_host;
1793 	target->srp_host   = host;
1794 
1795 	INIT_LIST_HEAD(&target->free_reqs);
1796 	INIT_LIST_HEAD(&target->req_queue);
1797 	for (i = 0; i < SRP_SQ_SIZE; ++i) {
1798 		target->req_ring[i].index = i;
1799 		list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1800 	}
1801 
1802 	ret = srp_parse_options(buf, target);
1803 	if (ret)
1804 		goto err;
1805 
1806 	ib_get_cached_gid(host->dev->dev, host->port, 0, &target->path.sgid);
1807 
1808 	printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1809 	       "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1810 	       (unsigned long long) be64_to_cpu(target->id_ext),
1811 	       (unsigned long long) be64_to_cpu(target->ioc_guid),
1812 	       be16_to_cpu(target->path.pkey),
1813 	       (unsigned long long) be64_to_cpu(target->service_id),
1814 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1815 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1816 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1817 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1818 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1819 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1820 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1821 	       (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1822 
1823 	ret = srp_create_target_ib(target);
1824 	if (ret)
1825 		goto err;
1826 
1827 	target->cm_id = ib_create_cm_id(host->dev->dev, srp_cm_handler, target);
1828 	if (IS_ERR(target->cm_id)) {
1829 		ret = PTR_ERR(target->cm_id);
1830 		goto err_free;
1831 	}
1832 
1833 	target->qp_in_error = 0;
1834 	ret = srp_connect_target(target);
1835 	if (ret) {
1836 		printk(KERN_ERR PFX "Connection failed\n");
1837 		goto err_cm_id;
1838 	}
1839 
1840 	ret = srp_add_target(host, target);
1841 	if (ret)
1842 		goto err_disconnect;
1843 
1844 	return count;
1845 
1846 err_disconnect:
1847 	srp_disconnect_target(target);
1848 
1849 err_cm_id:
1850 	ib_destroy_cm_id(target->cm_id);
1851 
1852 err_free:
1853 	srp_free_target_ib(target);
1854 
1855 err:
1856 	scsi_host_put(target_host);
1857 
1858 	return ret;
1859 }
1860 
1861 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1862 
1863 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1864 {
1865 	struct srp_host *host =
1866 		container_of(class_dev, struct srp_host, class_dev);
1867 
1868 	return sprintf(buf, "%s\n", host->dev->dev->name);
1869 }
1870 
1871 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1872 
1873 static ssize_t show_port(struct class_device *class_dev, char *buf)
1874 {
1875 	struct srp_host *host =
1876 		container_of(class_dev, struct srp_host, class_dev);
1877 
1878 	return sprintf(buf, "%d\n", host->port);
1879 }
1880 
1881 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1882 
1883 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
1884 {
1885 	struct srp_host *host;
1886 
1887 	host = kzalloc(sizeof *host, GFP_KERNEL);
1888 	if (!host)
1889 		return NULL;
1890 
1891 	INIT_LIST_HEAD(&host->target_list);
1892 	spin_lock_init(&host->target_lock);
1893 	init_completion(&host->released);
1894 	host->dev  = device;
1895 	host->port = port;
1896 
1897 	host->class_dev.class = &srp_class;
1898 	host->class_dev.dev   = device->dev->dma_device;
1899 	snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1900 		 device->dev->name, port);
1901 
1902 	if (class_device_register(&host->class_dev))
1903 		goto free_host;
1904 	if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1905 		goto err_class;
1906 	if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1907 		goto err_class;
1908 	if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1909 		goto err_class;
1910 
1911 	return host;
1912 
1913 err_class:
1914 	class_device_unregister(&host->class_dev);
1915 
1916 free_host:
1917 	kfree(host);
1918 
1919 	return NULL;
1920 }
1921 
1922 static void srp_add_one(struct ib_device *device)
1923 {
1924 	struct srp_device *srp_dev;
1925 	struct ib_device_attr *dev_attr;
1926 	struct ib_fmr_pool_param fmr_param;
1927 	struct srp_host *host;
1928 	int s, e, p;
1929 
1930 	dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
1931 	if (!dev_attr)
1932 		return;
1933 
1934 	if (ib_query_device(device, dev_attr)) {
1935 		printk(KERN_WARNING PFX "Query device failed for %s\n",
1936 		       device->name);
1937 		goto free_attr;
1938 	}
1939 
1940 	srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
1941 	if (!srp_dev)
1942 		goto free_attr;
1943 
1944 	/*
1945 	 * Use the smallest page size supported by the HCA, down to a
1946 	 * minimum of 512 bytes (which is the smallest sector that a
1947 	 * SCSI command will ever carry).
1948 	 */
1949 	srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
1950 	srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
1951 	srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);
1952 
1953 	INIT_LIST_HEAD(&srp_dev->dev_list);
1954 
1955 	srp_dev->dev = device;
1956 	srp_dev->pd  = ib_alloc_pd(device);
1957 	if (IS_ERR(srp_dev->pd))
1958 		goto free_dev;
1959 
1960 	srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
1961 				    IB_ACCESS_LOCAL_WRITE |
1962 				    IB_ACCESS_REMOTE_READ |
1963 				    IB_ACCESS_REMOTE_WRITE);
1964 	if (IS_ERR(srp_dev->mr))
1965 		goto err_pd;
1966 
1967 	memset(&fmr_param, 0, sizeof fmr_param);
1968 	fmr_param.pool_size	    = SRP_FMR_POOL_SIZE;
1969 	fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
1970 	fmr_param.cache		    = 1;
1971 	fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
1972 	fmr_param.page_shift	    = srp_dev->fmr_page_shift;
1973 	fmr_param.access	    = (IB_ACCESS_LOCAL_WRITE |
1974 				       IB_ACCESS_REMOTE_WRITE |
1975 				       IB_ACCESS_REMOTE_READ);
1976 
1977 	srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
1978 	if (IS_ERR(srp_dev->fmr_pool))
1979 		srp_dev->fmr_pool = NULL;
1980 
1981 	if (device->node_type == RDMA_NODE_IB_SWITCH) {
1982 		s = 0;
1983 		e = 0;
1984 	} else {
1985 		s = 1;
1986 		e = device->phys_port_cnt;
1987 	}
1988 
1989 	for (p = s; p <= e; ++p) {
1990 		host = srp_add_port(srp_dev, p);
1991 		if (host)
1992 			list_add_tail(&host->list, &srp_dev->dev_list);
1993 	}
1994 
1995 	ib_set_client_data(device, &srp_client, srp_dev);
1996 
1997 	goto free_attr;
1998 
1999 err_pd:
2000 	ib_dealloc_pd(srp_dev->pd);
2001 
2002 free_dev:
2003 	kfree(srp_dev);
2004 
2005 free_attr:
2006 	kfree(dev_attr);
2007 }
2008 
2009 static void srp_remove_one(struct ib_device *device)
2010 {
2011 	struct srp_device *srp_dev;
2012 	struct srp_host *host, *tmp_host;
2013 	LIST_HEAD(target_list);
2014 	struct srp_target_port *target, *tmp_target;
2015 
2016 	srp_dev = ib_get_client_data(device, &srp_client);
2017 
2018 	list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2019 		class_device_unregister(&host->class_dev);
2020 		/*
2021 		 * Wait for the sysfs entry to go away, so that no new
2022 		 * target ports can be created.
2023 		 */
2024 		wait_for_completion(&host->released);
2025 
2026 		/*
2027 		 * Mark all target ports as removed, so we stop queueing
2028 		 * commands and don't try to reconnect.
2029 		 */
2030 		spin_lock(&host->target_lock);
2031 		list_for_each_entry(target, &host->target_list, list) {
2032 			spin_lock_irq(target->scsi_host->host_lock);
2033 			target->state = SRP_TARGET_REMOVED;
2034 			spin_unlock_irq(target->scsi_host->host_lock);
2035 		}
2036 		spin_unlock(&host->target_lock);
2037 
2038 		/*
2039 		 * Wait for any reconnection tasks that may have
2040 		 * started before we marked our target ports as
2041 		 * removed, and any target port removal tasks.
2042 		 */
2043 		flush_scheduled_work();
2044 
2045 		list_for_each_entry_safe(target, tmp_target,
2046 					 &host->target_list, list) {
2047 			scsi_remove_host(target->scsi_host);
2048 			srp_disconnect_target(target);
2049 			ib_destroy_cm_id(target->cm_id);
2050 			srp_free_target_ib(target);
2051 			scsi_host_put(target->scsi_host);
2052 		}
2053 
2054 		kfree(host);
2055 	}
2056 
2057 	if (srp_dev->fmr_pool)
2058 		ib_destroy_fmr_pool(srp_dev->fmr_pool);
2059 	ib_dereg_mr(srp_dev->mr);
2060 	ib_dealloc_pd(srp_dev->pd);
2061 
2062 	kfree(srp_dev);
2063 }
2064 
2065 static int __init srp_init_module(void)
2066 {
2067 	int ret;
2068 
2069 	srp_template.sg_tablesize = srp_sg_tablesize;
2070 	srp_max_iu_len = (sizeof (struct srp_cmd) +
2071 			  sizeof (struct srp_indirect_buf) +
2072 			  srp_sg_tablesize * 16);
2073 
2074 	ret = class_register(&srp_class);
2075 	if (ret) {
2076 		printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
2077 		return ret;
2078 	}
2079 
2080 	ib_sa_register_client(&srp_sa_client);
2081 
2082 	ret = ib_register_client(&srp_client);
2083 	if (ret) {
2084 		printk(KERN_ERR PFX "couldn't register IB client\n");
2085 		ib_sa_unregister_client(&srp_sa_client);
2086 		class_unregister(&srp_class);
2087 		return ret;
2088 	}
2089 
2090 	return 0;
2091 }
2092 
2093 static void __exit srp_cleanup_module(void)
2094 {
2095 	ib_unregister_client(&srp_client);
2096 	ib_sa_unregister_client(&srp_sa_client);
2097 	class_unregister(&srp_class);
2098 }
2099 
2100 module_init(srp_init_module);
2101 module_exit(srp_cleanup_module);
2102