1 /*
2  * Copyright (c) 2006 Intel Corporation.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/completion.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/err.h>
36 #include <linux/interrupt.h>
37 #include <linux/bitops.h>
38 #include <linux/random.h>
39 
40 #include <rdma/ib_cache.h>
41 #include "sa.h"
42 
43 static void mcast_add_one(struct ib_device *device);
44 static void mcast_remove_one(struct ib_device *device);
45 
46 static struct ib_client mcast_client = {
47 	.name   = "ib_multicast",
48 	.add    = mcast_add_one,
49 	.remove = mcast_remove_one
50 };
51 
52 static struct ib_sa_client	sa_client;
53 static struct workqueue_struct	*mcast_wq;
54 static union ib_gid mgid0;
55 
56 struct mcast_device;
57 
58 struct mcast_port {
59 	struct mcast_device	*dev;
60 	spinlock_t		lock;
61 	struct rb_root		table;
62 	atomic_t		refcount;
63 	struct completion	comp;
64 	u8			port_num;
65 };
66 
67 struct mcast_device {
68 	struct ib_device	*device;
69 	struct ib_event_handler	event_handler;
70 	int			start_port;
71 	int			end_port;
72 	struct mcast_port	port[0];
73 };
74 
75 enum mcast_state {
76 	MCAST_IDLE,
77 	MCAST_JOINING,
78 	MCAST_MEMBER,
79 	MCAST_BUSY,
80 	MCAST_ERROR
81 };
82 
83 struct mcast_member;
84 
85 struct mcast_group {
86 	struct ib_sa_mcmember_rec rec;
87 	struct rb_node		node;
88 	struct mcast_port	*port;
89 	spinlock_t		lock;
90 	struct work_struct	work;
91 	struct list_head	pending_list;
92 	struct list_head	active_list;
93 	struct mcast_member	*last_join;
94 	int			members[3];
95 	atomic_t		refcount;
96 	enum mcast_state	state;
97 	struct ib_sa_query	*query;
98 	int			query_id;
99 };
100 
101 struct mcast_member {
102 	struct ib_sa_multicast	multicast;
103 	struct ib_sa_client	*client;
104 	struct mcast_group	*group;
105 	struct list_head	list;
106 	enum mcast_state	state;
107 	atomic_t		refcount;
108 	struct completion	comp;
109 };
110 
111 static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
112 			 void *context);
113 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
114 			  void *context);
115 
116 static struct mcast_group *mcast_find(struct mcast_port *port,
117 				      union ib_gid *mgid)
118 {
119 	struct rb_node *node = port->table.rb_node;
120 	struct mcast_group *group;
121 	int ret;
122 
123 	while (node) {
124 		group = rb_entry(node, struct mcast_group, node);
125 		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
126 		if (!ret)
127 			return group;
128 
129 		if (ret < 0)
130 			node = node->rb_left;
131 		else
132 			node = node->rb_right;
133 	}
134 	return NULL;
135 }
136 
137 static struct mcast_group *mcast_insert(struct mcast_port *port,
138 					struct mcast_group *group,
139 					int allow_duplicates)
140 {
141 	struct rb_node **link = &port->table.rb_node;
142 	struct rb_node *parent = NULL;
143 	struct mcast_group *cur_group;
144 	int ret;
145 
146 	while (*link) {
147 		parent = *link;
148 		cur_group = rb_entry(parent, struct mcast_group, node);
149 
150 		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
151 			     sizeof group->rec.mgid);
152 		if (ret < 0)
153 			link = &(*link)->rb_left;
154 		else if (ret > 0)
155 			link = &(*link)->rb_right;
156 		else if (allow_duplicates)
157 			link = &(*link)->rb_left;
158 		else
159 			return cur_group;
160 	}
161 	rb_link_node(&group->node, parent, link);
162 	rb_insert_color(&group->node, &port->table);
163 	return NULL;
164 }
165 
166 static void deref_port(struct mcast_port *port)
167 {
168 	if (atomic_dec_and_test(&port->refcount))
169 		complete(&port->comp);
170 }
171 
172 static void release_group(struct mcast_group *group)
173 {
174 	struct mcast_port *port = group->port;
175 	unsigned long flags;
176 
177 	spin_lock_irqsave(&port->lock, flags);
178 	if (atomic_dec_and_test(&group->refcount)) {
179 		rb_erase(&group->node, &port->table);
180 		spin_unlock_irqrestore(&port->lock, flags);
181 		kfree(group);
182 		deref_port(port);
183 	} else
184 		spin_unlock_irqrestore(&port->lock, flags);
185 }
186 
187 static void deref_member(struct mcast_member *member)
188 {
189 	if (atomic_dec_and_test(&member->refcount))
190 		complete(&member->comp);
191 }
192 
193 static void queue_join(struct mcast_member *member)
194 {
195 	struct mcast_group *group = member->group;
196 	unsigned long flags;
197 
198 	spin_lock_irqsave(&group->lock, flags);
199 	list_add(&member->list, &group->pending_list);
200 	if (group->state == MCAST_IDLE) {
201 		group->state = MCAST_BUSY;
202 		atomic_inc(&group->refcount);
203 		queue_work(mcast_wq, &group->work);
204 	}
205 	spin_unlock_irqrestore(&group->lock, flags);
206 }
207 
208 /*
209  * A multicast group has three types of members: full member, non member, and
210  * send only member.  We need to keep track of the number of members of each
211  * type based on their join state.  Adjust the number of members the belong to
212  * the specified join states.
213  */
214 static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
215 {
216 	int i;
217 
218 	for (i = 0; i < 3; i++, join_state >>= 1)
219 		if (join_state & 0x1)
220 			group->members[i] += inc;
221 }
222 
223 /*
224  * If a multicast group has zero members left for a particular join state, but
225  * the group is still a member with the SA, we need to leave that join state.
226  * Determine which join states we still belong to, but that do not have any
227  * active members.
228  */
229 static u8 get_leave_state(struct mcast_group *group)
230 {
231 	u8 leave_state = 0;
232 	int i;
233 
234 	for (i = 0; i < 3; i++)
235 		if (!group->members[i])
236 			leave_state |= (0x1 << i);
237 
238 	return leave_state & group->rec.join_state;
239 }
240 
241 static int check_selector(ib_sa_comp_mask comp_mask,
242 			  ib_sa_comp_mask selector_mask,
243 			  ib_sa_comp_mask value_mask,
244 			  u8 selector, u8 src_value, u8 dst_value)
245 {
246 	int err;
247 
248 	if (!(comp_mask & selector_mask) || !(comp_mask & value_mask))
249 		return 0;
250 
251 	switch (selector) {
252 	case IB_SA_GT:
253 		err = (src_value <= dst_value);
254 		break;
255 	case IB_SA_LT:
256 		err = (src_value >= dst_value);
257 		break;
258 	case IB_SA_EQ:
259 		err = (src_value != dst_value);
260 		break;
261 	default:
262 		err = 0;
263 		break;
264 	}
265 
266 	return err;
267 }
268 
269 static int cmp_rec(struct ib_sa_mcmember_rec *src,
270 		   struct ib_sa_mcmember_rec *dst, ib_sa_comp_mask comp_mask)
271 {
272 	/* MGID must already match */
273 
274 	if (comp_mask & IB_SA_MCMEMBER_REC_PORT_GID &&
275 	    memcmp(&src->port_gid, &dst->port_gid, sizeof src->port_gid))
276 		return -EINVAL;
277 	if (comp_mask & IB_SA_MCMEMBER_REC_QKEY && src->qkey != dst->qkey)
278 		return -EINVAL;
279 	if (comp_mask & IB_SA_MCMEMBER_REC_MLID && src->mlid != dst->mlid)
280 		return -EINVAL;
281 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_MTU_SELECTOR,
282 			   IB_SA_MCMEMBER_REC_MTU, dst->mtu_selector,
283 			   src->mtu, dst->mtu))
284 		return -EINVAL;
285 	if (comp_mask & IB_SA_MCMEMBER_REC_TRAFFIC_CLASS &&
286 	    src->traffic_class != dst->traffic_class)
287 		return -EINVAL;
288 	if (comp_mask & IB_SA_MCMEMBER_REC_PKEY && src->pkey != dst->pkey)
289 		return -EINVAL;
290 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_RATE_SELECTOR,
291 			   IB_SA_MCMEMBER_REC_RATE, dst->rate_selector,
292 			   src->rate, dst->rate))
293 		return -EINVAL;
294 	if (check_selector(comp_mask,
295 			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME_SELECTOR,
296 			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME,
297 			   dst->packet_life_time_selector,
298 			   src->packet_life_time, dst->packet_life_time))
299 		return -EINVAL;
300 	if (comp_mask & IB_SA_MCMEMBER_REC_SL && src->sl != dst->sl)
301 		return -EINVAL;
302 	if (comp_mask & IB_SA_MCMEMBER_REC_FLOW_LABEL &&
303 	    src->flow_label != dst->flow_label)
304 		return -EINVAL;
305 	if (comp_mask & IB_SA_MCMEMBER_REC_HOP_LIMIT &&
306 	    src->hop_limit != dst->hop_limit)
307 		return -EINVAL;
308 	if (comp_mask & IB_SA_MCMEMBER_REC_SCOPE && src->scope != dst->scope)
309 		return -EINVAL;
310 
311 	/* join_state checked separately, proxy_join ignored */
312 
313 	return 0;
314 }
315 
316 static int send_join(struct mcast_group *group, struct mcast_member *member)
317 {
318 	struct mcast_port *port = group->port;
319 	int ret;
320 
321 	group->last_join = member;
322 	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
323 				       port->port_num, IB_MGMT_METHOD_SET,
324 				       &member->multicast.rec,
325 				       member->multicast.comp_mask,
326 				       3000, GFP_KERNEL, join_handler, group,
327 				       &group->query);
328 	if (ret >= 0) {
329 		group->query_id = ret;
330 		ret = 0;
331 	}
332 	return ret;
333 }
334 
335 static int send_leave(struct mcast_group *group, u8 leave_state)
336 {
337 	struct mcast_port *port = group->port;
338 	struct ib_sa_mcmember_rec rec;
339 	int ret;
340 
341 	rec = group->rec;
342 	rec.join_state = leave_state;
343 
344 	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
345 				       port->port_num, IB_SA_METHOD_DELETE, &rec,
346 				       IB_SA_MCMEMBER_REC_MGID     |
347 				       IB_SA_MCMEMBER_REC_PORT_GID |
348 				       IB_SA_MCMEMBER_REC_JOIN_STATE,
349 				       3000, GFP_KERNEL, leave_handler,
350 				       group, &group->query);
351 	if (ret >= 0) {
352 		group->query_id = ret;
353 		ret = 0;
354 	}
355 	return ret;
356 }
357 
358 static void join_group(struct mcast_group *group, struct mcast_member *member,
359 		       u8 join_state)
360 {
361 	member->state = MCAST_MEMBER;
362 	adjust_membership(group, join_state, 1);
363 	group->rec.join_state |= join_state;
364 	member->multicast.rec = group->rec;
365 	member->multicast.rec.join_state = join_state;
366 	list_move(&member->list, &group->active_list);
367 }
368 
369 static int fail_join(struct mcast_group *group, struct mcast_member *member,
370 		     int status)
371 {
372 	spin_lock_irq(&group->lock);
373 	list_del_init(&member->list);
374 	spin_unlock_irq(&group->lock);
375 	return member->multicast.callback(status, &member->multicast);
376 }
377 
378 static void process_group_error(struct mcast_group *group)
379 {
380 	struct mcast_member *member;
381 	int ret;
382 
383 	spin_lock_irq(&group->lock);
384 	while (!list_empty(&group->active_list)) {
385 		member = list_entry(group->active_list.next,
386 				    struct mcast_member, list);
387 		atomic_inc(&member->refcount);
388 		list_del_init(&member->list);
389 		adjust_membership(group, member->multicast.rec.join_state, -1);
390 		member->state = MCAST_ERROR;
391 		spin_unlock_irq(&group->lock);
392 
393 		ret = member->multicast.callback(-ENETRESET,
394 						 &member->multicast);
395 		deref_member(member);
396 		if (ret)
397 			ib_sa_free_multicast(&member->multicast);
398 		spin_lock_irq(&group->lock);
399 	}
400 
401 	group->rec.join_state = 0;
402 	group->state = MCAST_BUSY;
403 	spin_unlock_irq(&group->lock);
404 }
405 
406 static void mcast_work_handler(struct work_struct *work)
407 {
408 	struct mcast_group *group;
409 	struct mcast_member *member;
410 	struct ib_sa_multicast *multicast;
411 	int status, ret;
412 	u8 join_state;
413 
414 	group = container_of(work, typeof(*group), work);
415 retest:
416 	spin_lock_irq(&group->lock);
417 	while (!list_empty(&group->pending_list) ||
418 	       (group->state == MCAST_ERROR)) {
419 
420 		if (group->state == MCAST_ERROR) {
421 			spin_unlock_irq(&group->lock);
422 			process_group_error(group);
423 			goto retest;
424 		}
425 
426 		member = list_entry(group->pending_list.next,
427 				    struct mcast_member, list);
428 		multicast = &member->multicast;
429 		join_state = multicast->rec.join_state;
430 		atomic_inc(&member->refcount);
431 
432 		if (join_state == (group->rec.join_state & join_state)) {
433 			status = cmp_rec(&group->rec, &multicast->rec,
434 					 multicast->comp_mask);
435 			if (!status)
436 				join_group(group, member, join_state);
437 			else
438 				list_del_init(&member->list);
439 			spin_unlock_irq(&group->lock);
440 			ret = multicast->callback(status, multicast);
441 		} else {
442 			spin_unlock_irq(&group->lock);
443 			status = send_join(group, member);
444 			if (!status) {
445 				deref_member(member);
446 				return;
447 			}
448 			ret = fail_join(group, member, status);
449 		}
450 
451 		deref_member(member);
452 		if (ret)
453 			ib_sa_free_multicast(&member->multicast);
454 		spin_lock_irq(&group->lock);
455 	}
456 
457 	join_state = get_leave_state(group);
458 	if (join_state) {
459 		group->rec.join_state &= ~join_state;
460 		spin_unlock_irq(&group->lock);
461 		if (send_leave(group, join_state))
462 			goto retest;
463 	} else {
464 		group->state = MCAST_IDLE;
465 		spin_unlock_irq(&group->lock);
466 		release_group(group);
467 	}
468 }
469 
470 /*
471  * Fail a join request if it is still active - at the head of the pending queue.
472  */
473 static void process_join_error(struct mcast_group *group, int status)
474 {
475 	struct mcast_member *member;
476 	int ret;
477 
478 	spin_lock_irq(&group->lock);
479 	member = list_entry(group->pending_list.next,
480 			    struct mcast_member, list);
481 	if (group->last_join == member) {
482 		atomic_inc(&member->refcount);
483 		list_del_init(&member->list);
484 		spin_unlock_irq(&group->lock);
485 		ret = member->multicast.callback(status, &member->multicast);
486 		deref_member(member);
487 		if (ret)
488 			ib_sa_free_multicast(&member->multicast);
489 	} else
490 		spin_unlock_irq(&group->lock);
491 }
492 
493 static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
494 			 void *context)
495 {
496 	struct mcast_group *group = context;
497 
498 	if (status)
499 		process_join_error(group, status);
500 	else {
501 		spin_lock_irq(&group->port->lock);
502 		group->rec = *rec;
503 		if (!memcmp(&mgid0, &group->rec.mgid, sizeof mgid0)) {
504 			rb_erase(&group->node, &group->port->table);
505 			mcast_insert(group->port, group, 1);
506 		}
507 		spin_unlock_irq(&group->port->lock);
508 	}
509 	mcast_work_handler(&group->work);
510 }
511 
512 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
513 			  void *context)
514 {
515 	struct mcast_group *group = context;
516 
517 	mcast_work_handler(&group->work);
518 }
519 
520 static struct mcast_group *acquire_group(struct mcast_port *port,
521 					 union ib_gid *mgid, gfp_t gfp_mask)
522 {
523 	struct mcast_group *group, *cur_group;
524 	unsigned long flags;
525 	int is_mgid0;
526 
527 	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
528 	if (!is_mgid0) {
529 		spin_lock_irqsave(&port->lock, flags);
530 		group = mcast_find(port, mgid);
531 		if (group)
532 			goto found;
533 		spin_unlock_irqrestore(&port->lock, flags);
534 	}
535 
536 	group = kzalloc(sizeof *group, gfp_mask);
537 	if (!group)
538 		return NULL;
539 
540 	group->port = port;
541 	group->rec.mgid = *mgid;
542 	INIT_LIST_HEAD(&group->pending_list);
543 	INIT_LIST_HEAD(&group->active_list);
544 	INIT_WORK(&group->work, mcast_work_handler);
545 	spin_lock_init(&group->lock);
546 
547 	spin_lock_irqsave(&port->lock, flags);
548 	cur_group = mcast_insert(port, group, is_mgid0);
549 	if (cur_group) {
550 		kfree(group);
551 		group = cur_group;
552 	} else
553 		atomic_inc(&port->refcount);
554 found:
555 	atomic_inc(&group->refcount);
556 	spin_unlock_irqrestore(&port->lock, flags);
557 	return group;
558 }
559 
560 /*
561  * We serialize all join requests to a single group to make our lives much
562  * easier.  Otherwise, two users could try to join the same group
563  * simultaneously, with different configurations, one could leave while the
564  * join is in progress, etc., which makes locking around error recovery
565  * difficult.
566  */
567 struct ib_sa_multicast *
568 ib_sa_join_multicast(struct ib_sa_client *client,
569 		     struct ib_device *device, u8 port_num,
570 		     struct ib_sa_mcmember_rec *rec,
571 		     ib_sa_comp_mask comp_mask, gfp_t gfp_mask,
572 		     int (*callback)(int status,
573 				     struct ib_sa_multicast *multicast),
574 		     void *context)
575 {
576 	struct mcast_device *dev;
577 	struct mcast_member *member;
578 	struct ib_sa_multicast *multicast;
579 	int ret;
580 
581 	dev = ib_get_client_data(device, &mcast_client);
582 	if (!dev)
583 		return ERR_PTR(-ENODEV);
584 
585 	member = kmalloc(sizeof *member, gfp_mask);
586 	if (!member)
587 		return ERR_PTR(-ENOMEM);
588 
589 	ib_sa_client_get(client);
590 	member->client = client;
591 	member->multicast.rec = *rec;
592 	member->multicast.comp_mask = comp_mask;
593 	member->multicast.callback = callback;
594 	member->multicast.context = context;
595 	init_completion(&member->comp);
596 	atomic_set(&member->refcount, 1);
597 	member->state = MCAST_JOINING;
598 
599 	member->group = acquire_group(&dev->port[port_num - dev->start_port],
600 				      &rec->mgid, gfp_mask);
601 	if (!member->group) {
602 		ret = -ENOMEM;
603 		goto err;
604 	}
605 
606 	/*
607 	 * The user will get the multicast structure in their callback.  They
608 	 * could then free the multicast structure before we can return from
609 	 * this routine.  So we save the pointer to return before queuing
610 	 * any callback.
611 	 */
612 	multicast = &member->multicast;
613 	queue_join(member);
614 	return multicast;
615 
616 err:
617 	ib_sa_client_put(client);
618 	kfree(member);
619 	return ERR_PTR(ret);
620 }
621 EXPORT_SYMBOL(ib_sa_join_multicast);
622 
623 void ib_sa_free_multicast(struct ib_sa_multicast *multicast)
624 {
625 	struct mcast_member *member;
626 	struct mcast_group *group;
627 
628 	member = container_of(multicast, struct mcast_member, multicast);
629 	group = member->group;
630 
631 	spin_lock_irq(&group->lock);
632 	if (member->state == MCAST_MEMBER)
633 		adjust_membership(group, multicast->rec.join_state, -1);
634 
635 	list_del_init(&member->list);
636 
637 	if (group->state == MCAST_IDLE) {
638 		group->state = MCAST_BUSY;
639 		spin_unlock_irq(&group->lock);
640 		/* Continue to hold reference on group until callback */
641 		queue_work(mcast_wq, &group->work);
642 	} else {
643 		spin_unlock_irq(&group->lock);
644 		release_group(group);
645 	}
646 
647 	deref_member(member);
648 	wait_for_completion(&member->comp);
649 	ib_sa_client_put(member->client);
650 	kfree(member);
651 }
652 EXPORT_SYMBOL(ib_sa_free_multicast);
653 
654 int ib_sa_get_mcmember_rec(struct ib_device *device, u8 port_num,
655 			   union ib_gid *mgid, struct ib_sa_mcmember_rec *rec)
656 {
657 	struct mcast_device *dev;
658 	struct mcast_port *port;
659 	struct mcast_group *group;
660 	unsigned long flags;
661 	int ret = 0;
662 
663 	dev = ib_get_client_data(device, &mcast_client);
664 	if (!dev)
665 		return -ENODEV;
666 
667 	port = &dev->port[port_num - dev->start_port];
668 	spin_lock_irqsave(&port->lock, flags);
669 	group = mcast_find(port, mgid);
670 	if (group)
671 		*rec = group->rec;
672 	else
673 		ret = -EADDRNOTAVAIL;
674 	spin_unlock_irqrestore(&port->lock, flags);
675 
676 	return ret;
677 }
678 EXPORT_SYMBOL(ib_sa_get_mcmember_rec);
679 
680 int ib_init_ah_from_mcmember(struct ib_device *device, u8 port_num,
681 			     struct ib_sa_mcmember_rec *rec,
682 			     struct ib_ah_attr *ah_attr)
683 {
684 	int ret;
685 	u16 gid_index;
686 	u8 p;
687 
688 	ret = ib_find_cached_gid(device, &rec->port_gid, &p, &gid_index);
689 	if (ret)
690 		return ret;
691 
692 	memset(ah_attr, 0, sizeof *ah_attr);
693 	ah_attr->dlid = be16_to_cpu(rec->mlid);
694 	ah_attr->sl = rec->sl;
695 	ah_attr->port_num = port_num;
696 	ah_attr->static_rate = rec->rate;
697 
698 	ah_attr->ah_flags = IB_AH_GRH;
699 	ah_attr->grh.dgid = rec->mgid;
700 
701 	ah_attr->grh.sgid_index = (u8) gid_index;
702 	ah_attr->grh.flow_label = be32_to_cpu(rec->flow_label);
703 	ah_attr->grh.hop_limit = rec->hop_limit;
704 	ah_attr->grh.traffic_class = rec->traffic_class;
705 
706 	return 0;
707 }
708 EXPORT_SYMBOL(ib_init_ah_from_mcmember);
709 
710 static void mcast_groups_lost(struct mcast_port *port)
711 {
712 	struct mcast_group *group;
713 	struct rb_node *node;
714 	unsigned long flags;
715 
716 	spin_lock_irqsave(&port->lock, flags);
717 	for (node = rb_first(&port->table); node; node = rb_next(node)) {
718 		group = rb_entry(node, struct mcast_group, node);
719 		spin_lock(&group->lock);
720 		if (group->state == MCAST_IDLE) {
721 			atomic_inc(&group->refcount);
722 			queue_work(mcast_wq, &group->work);
723 		}
724 		group->state = MCAST_ERROR;
725 		spin_unlock(&group->lock);
726 	}
727 	spin_unlock_irqrestore(&port->lock, flags);
728 }
729 
730 static void mcast_event_handler(struct ib_event_handler *handler,
731 				struct ib_event *event)
732 {
733 	struct mcast_device *dev;
734 
735 	dev = container_of(handler, struct mcast_device, event_handler);
736 
737 	switch (event->event) {
738 	case IB_EVENT_PORT_ERR:
739 	case IB_EVENT_LID_CHANGE:
740 	case IB_EVENT_SM_CHANGE:
741 	case IB_EVENT_CLIENT_REREGISTER:
742 		mcast_groups_lost(&dev->port[event->element.port_num -
743 					     dev->start_port]);
744 		break;
745 	default:
746 		break;
747 	}
748 }
749 
750 static void mcast_add_one(struct ib_device *device)
751 {
752 	struct mcast_device *dev;
753 	struct mcast_port *port;
754 	int i;
755 
756 	if (rdma_node_get_transport(device->node_type) != RDMA_TRANSPORT_IB)
757 		return;
758 
759 	dev = kmalloc(sizeof *dev + device->phys_port_cnt * sizeof *port,
760 		      GFP_KERNEL);
761 	if (!dev)
762 		return;
763 
764 	if (device->node_type == RDMA_NODE_IB_SWITCH)
765 		dev->start_port = dev->end_port = 0;
766 	else {
767 		dev->start_port = 1;
768 		dev->end_port = device->phys_port_cnt;
769 	}
770 
771 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
772 		port = &dev->port[i];
773 		port->dev = dev;
774 		port->port_num = dev->start_port + i;
775 		spin_lock_init(&port->lock);
776 		port->table = RB_ROOT;
777 		init_completion(&port->comp);
778 		atomic_set(&port->refcount, 1);
779 	}
780 
781 	dev->device = device;
782 	ib_set_client_data(device, &mcast_client, dev);
783 
784 	INIT_IB_EVENT_HANDLER(&dev->event_handler, device, mcast_event_handler);
785 	ib_register_event_handler(&dev->event_handler);
786 }
787 
788 static void mcast_remove_one(struct ib_device *device)
789 {
790 	struct mcast_device *dev;
791 	struct mcast_port *port;
792 	int i;
793 
794 	dev = ib_get_client_data(device, &mcast_client);
795 	if (!dev)
796 		return;
797 
798 	ib_unregister_event_handler(&dev->event_handler);
799 	flush_workqueue(mcast_wq);
800 
801 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
802 		port = &dev->port[i];
803 		deref_port(port);
804 		wait_for_completion(&port->comp);
805 	}
806 
807 	kfree(dev);
808 }
809 
810 int mcast_init(void)
811 {
812 	int ret;
813 
814 	mcast_wq = create_singlethread_workqueue("ib_mcast");
815 	if (!mcast_wq)
816 		return -ENOMEM;
817 
818 	ib_sa_register_client(&sa_client);
819 
820 	ret = ib_register_client(&mcast_client);
821 	if (ret)
822 		goto err;
823 	return 0;
824 
825 err:
826 	ib_sa_unregister_client(&sa_client);
827 	destroy_workqueue(mcast_wq);
828 	return ret;
829 }
830 
831 void mcast_cleanup(void)
832 {
833 	ib_unregister_client(&mcast_client);
834 	ib_sa_unregister_client(&sa_client);
835 	destroy_workqueue(mcast_wq);
836 }
837