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/export.h>
38 #include <linux/slab.h>
39 #include <linux/bitops.h>
40 #include <linux/random.h>
41 
42 #include <rdma/ib_cache.h>
43 #include "sa.h"
44 
45 static void mcast_add_one(struct ib_device *device);
46 static void mcast_remove_one(struct ib_device *device, void *client_data);
47 
48 static struct ib_client mcast_client = {
49 	.name   = "ib_multicast",
50 	.add    = mcast_add_one,
51 	.remove = mcast_remove_one
52 };
53 
54 static struct ib_sa_client	sa_client;
55 static struct workqueue_struct	*mcast_wq;
56 static union ib_gid mgid0;
57 
58 struct mcast_device;
59 
60 struct mcast_port {
61 	struct mcast_device	*dev;
62 	spinlock_t		lock;
63 	struct rb_root		table;
64 	atomic_t		refcount;
65 	struct completion	comp;
66 	u8			port_num;
67 };
68 
69 struct mcast_device {
70 	struct ib_device	*device;
71 	struct ib_event_handler	event_handler;
72 	int			start_port;
73 	int			end_port;
74 	struct mcast_port	port[0];
75 };
76 
77 enum mcast_state {
78 	MCAST_JOINING,
79 	MCAST_MEMBER,
80 	MCAST_ERROR,
81 };
82 
83 enum mcast_group_state {
84 	MCAST_IDLE,
85 	MCAST_BUSY,
86 	MCAST_GROUP_ERROR,
87 	MCAST_PKEY_EVENT
88 };
89 
90 enum {
91 	MCAST_INVALID_PKEY_INDEX = 0xFFFF
92 };
93 
94 struct mcast_member;
95 
96 /*
97 * There are 4 types of join states:
98 * FullMember, NonMember, SendOnlyNonMember, SendOnlyFullMember.
99 */
100 enum {
101 	FULLMEMBER_JOIN,
102 	NONMEMBER_JOIN,
103 	SENDONLY_NONMEBER_JOIN,
104 	SENDONLY_FULLMEMBER_JOIN,
105 	NUM_JOIN_MEMBERSHIP_TYPES,
106 };
107 
108 struct mcast_group {
109 	struct ib_sa_mcmember_rec rec;
110 	struct rb_node		node;
111 	struct mcast_port	*port;
112 	spinlock_t		lock;
113 	struct work_struct	work;
114 	struct list_head	pending_list;
115 	struct list_head	active_list;
116 	struct mcast_member	*last_join;
117 	int			members[NUM_JOIN_MEMBERSHIP_TYPES];
118 	atomic_t		refcount;
119 	enum mcast_group_state	state;
120 	struct ib_sa_query	*query;
121 	int			query_id;
122 	u16			pkey_index;
123 	u8			leave_state;
124 	int			retries;
125 };
126 
127 struct mcast_member {
128 	struct ib_sa_multicast	multicast;
129 	struct ib_sa_client	*client;
130 	struct mcast_group	*group;
131 	struct list_head	list;
132 	enum mcast_state	state;
133 	atomic_t		refcount;
134 	struct completion	comp;
135 };
136 
137 static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
138 			 void *context);
139 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
140 			  void *context);
141 
142 static struct mcast_group *mcast_find(struct mcast_port *port,
143 				      union ib_gid *mgid)
144 {
145 	struct rb_node *node = port->table.rb_node;
146 	struct mcast_group *group;
147 	int ret;
148 
149 	while (node) {
150 		group = rb_entry(node, struct mcast_group, node);
151 		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
152 		if (!ret)
153 			return group;
154 
155 		if (ret < 0)
156 			node = node->rb_left;
157 		else
158 			node = node->rb_right;
159 	}
160 	return NULL;
161 }
162 
163 static struct mcast_group *mcast_insert(struct mcast_port *port,
164 					struct mcast_group *group,
165 					int allow_duplicates)
166 {
167 	struct rb_node **link = &port->table.rb_node;
168 	struct rb_node *parent = NULL;
169 	struct mcast_group *cur_group;
170 	int ret;
171 
172 	while (*link) {
173 		parent = *link;
174 		cur_group = rb_entry(parent, struct mcast_group, node);
175 
176 		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
177 			     sizeof group->rec.mgid);
178 		if (ret < 0)
179 			link = &(*link)->rb_left;
180 		else if (ret > 0)
181 			link = &(*link)->rb_right;
182 		else if (allow_duplicates)
183 			link = &(*link)->rb_left;
184 		else
185 			return cur_group;
186 	}
187 	rb_link_node(&group->node, parent, link);
188 	rb_insert_color(&group->node, &port->table);
189 	return NULL;
190 }
191 
192 static void deref_port(struct mcast_port *port)
193 {
194 	if (atomic_dec_and_test(&port->refcount))
195 		complete(&port->comp);
196 }
197 
198 static void release_group(struct mcast_group *group)
199 {
200 	struct mcast_port *port = group->port;
201 	unsigned long flags;
202 
203 	spin_lock_irqsave(&port->lock, flags);
204 	if (atomic_dec_and_test(&group->refcount)) {
205 		rb_erase(&group->node, &port->table);
206 		spin_unlock_irqrestore(&port->lock, flags);
207 		kfree(group);
208 		deref_port(port);
209 	} else
210 		spin_unlock_irqrestore(&port->lock, flags);
211 }
212 
213 static void deref_member(struct mcast_member *member)
214 {
215 	if (atomic_dec_and_test(&member->refcount))
216 		complete(&member->comp);
217 }
218 
219 static void queue_join(struct mcast_member *member)
220 {
221 	struct mcast_group *group = member->group;
222 	unsigned long flags;
223 
224 	spin_lock_irqsave(&group->lock, flags);
225 	list_add_tail(&member->list, &group->pending_list);
226 	if (group->state == MCAST_IDLE) {
227 		group->state = MCAST_BUSY;
228 		atomic_inc(&group->refcount);
229 		queue_work(mcast_wq, &group->work);
230 	}
231 	spin_unlock_irqrestore(&group->lock, flags);
232 }
233 
234 /*
235  * A multicast group has four types of members: full member, non member,
236  * sendonly non member and sendonly full member.
237  * We need to keep track of the number of members of each
238  * type based on their join state.  Adjust the number of members the belong to
239  * the specified join states.
240  */
241 static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
242 {
243 	int i;
244 
245 	for (i = 0; i < NUM_JOIN_MEMBERSHIP_TYPES; i++, join_state >>= 1)
246 		if (join_state & 0x1)
247 			group->members[i] += inc;
248 }
249 
250 /*
251  * If a multicast group has zero members left for a particular join state, but
252  * the group is still a member with the SA, we need to leave that join state.
253  * Determine which join states we still belong to, but that do not have any
254  * active members.
255  */
256 static u8 get_leave_state(struct mcast_group *group)
257 {
258 	u8 leave_state = 0;
259 	int i;
260 
261 	for (i = 0; i < NUM_JOIN_MEMBERSHIP_TYPES; i++)
262 		if (!group->members[i])
263 			leave_state |= (0x1 << i);
264 
265 	return leave_state & group->rec.join_state;
266 }
267 
268 static int check_selector(ib_sa_comp_mask comp_mask,
269 			  ib_sa_comp_mask selector_mask,
270 			  ib_sa_comp_mask value_mask,
271 			  u8 selector, u8 src_value, u8 dst_value)
272 {
273 	int err;
274 
275 	if (!(comp_mask & selector_mask) || !(comp_mask & value_mask))
276 		return 0;
277 
278 	switch (selector) {
279 	case IB_SA_GT:
280 		err = (src_value <= dst_value);
281 		break;
282 	case IB_SA_LT:
283 		err = (src_value >= dst_value);
284 		break;
285 	case IB_SA_EQ:
286 		err = (src_value != dst_value);
287 		break;
288 	default:
289 		err = 0;
290 		break;
291 	}
292 
293 	return err;
294 }
295 
296 static int cmp_rec(struct ib_sa_mcmember_rec *src,
297 		   struct ib_sa_mcmember_rec *dst, ib_sa_comp_mask comp_mask)
298 {
299 	/* MGID must already match */
300 
301 	if (comp_mask & IB_SA_MCMEMBER_REC_PORT_GID &&
302 	    memcmp(&src->port_gid, &dst->port_gid, sizeof src->port_gid))
303 		return -EINVAL;
304 	if (comp_mask & IB_SA_MCMEMBER_REC_QKEY && src->qkey != dst->qkey)
305 		return -EINVAL;
306 	if (comp_mask & IB_SA_MCMEMBER_REC_MLID && src->mlid != dst->mlid)
307 		return -EINVAL;
308 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_MTU_SELECTOR,
309 			   IB_SA_MCMEMBER_REC_MTU, dst->mtu_selector,
310 			   src->mtu, dst->mtu))
311 		return -EINVAL;
312 	if (comp_mask & IB_SA_MCMEMBER_REC_TRAFFIC_CLASS &&
313 	    src->traffic_class != dst->traffic_class)
314 		return -EINVAL;
315 	if (comp_mask & IB_SA_MCMEMBER_REC_PKEY && src->pkey != dst->pkey)
316 		return -EINVAL;
317 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_RATE_SELECTOR,
318 			   IB_SA_MCMEMBER_REC_RATE, dst->rate_selector,
319 			   src->rate, dst->rate))
320 		return -EINVAL;
321 	if (check_selector(comp_mask,
322 			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME_SELECTOR,
323 			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME,
324 			   dst->packet_life_time_selector,
325 			   src->packet_life_time, dst->packet_life_time))
326 		return -EINVAL;
327 	if (comp_mask & IB_SA_MCMEMBER_REC_SL && src->sl != dst->sl)
328 		return -EINVAL;
329 	if (comp_mask & IB_SA_MCMEMBER_REC_FLOW_LABEL &&
330 	    src->flow_label != dst->flow_label)
331 		return -EINVAL;
332 	if (comp_mask & IB_SA_MCMEMBER_REC_HOP_LIMIT &&
333 	    src->hop_limit != dst->hop_limit)
334 		return -EINVAL;
335 	if (comp_mask & IB_SA_MCMEMBER_REC_SCOPE && src->scope != dst->scope)
336 		return -EINVAL;
337 
338 	/* join_state checked separately, proxy_join ignored */
339 
340 	return 0;
341 }
342 
343 static int send_join(struct mcast_group *group, struct mcast_member *member)
344 {
345 	struct mcast_port *port = group->port;
346 	int ret;
347 
348 	group->last_join = member;
349 	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
350 				       port->port_num, IB_MGMT_METHOD_SET,
351 				       &member->multicast.rec,
352 				       member->multicast.comp_mask,
353 				       3000, GFP_KERNEL, join_handler, group,
354 				       &group->query);
355 	if (ret >= 0) {
356 		group->query_id = ret;
357 		ret = 0;
358 	}
359 	return ret;
360 }
361 
362 static int send_leave(struct mcast_group *group, u8 leave_state)
363 {
364 	struct mcast_port *port = group->port;
365 	struct ib_sa_mcmember_rec rec;
366 	int ret;
367 
368 	rec = group->rec;
369 	rec.join_state = leave_state;
370 	group->leave_state = leave_state;
371 
372 	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
373 				       port->port_num, IB_SA_METHOD_DELETE, &rec,
374 				       IB_SA_MCMEMBER_REC_MGID     |
375 				       IB_SA_MCMEMBER_REC_PORT_GID |
376 				       IB_SA_MCMEMBER_REC_JOIN_STATE,
377 				       3000, GFP_KERNEL, leave_handler,
378 				       group, &group->query);
379 	if (ret >= 0) {
380 		group->query_id = ret;
381 		ret = 0;
382 	}
383 	return ret;
384 }
385 
386 static void join_group(struct mcast_group *group, struct mcast_member *member,
387 		       u8 join_state)
388 {
389 	member->state = MCAST_MEMBER;
390 	adjust_membership(group, join_state, 1);
391 	group->rec.join_state |= join_state;
392 	member->multicast.rec = group->rec;
393 	member->multicast.rec.join_state = join_state;
394 	list_move(&member->list, &group->active_list);
395 }
396 
397 static int fail_join(struct mcast_group *group, struct mcast_member *member,
398 		     int status)
399 {
400 	spin_lock_irq(&group->lock);
401 	list_del_init(&member->list);
402 	spin_unlock_irq(&group->lock);
403 	return member->multicast.callback(status, &member->multicast);
404 }
405 
406 static void process_group_error(struct mcast_group *group)
407 {
408 	struct mcast_member *member;
409 	int ret = 0;
410 	u16 pkey_index;
411 
412 	if (group->state == MCAST_PKEY_EVENT)
413 		ret = ib_find_pkey(group->port->dev->device,
414 				   group->port->port_num,
415 				   be16_to_cpu(group->rec.pkey), &pkey_index);
416 
417 	spin_lock_irq(&group->lock);
418 	if (group->state == MCAST_PKEY_EVENT && !ret &&
419 	    group->pkey_index == pkey_index)
420 		goto out;
421 
422 	while (!list_empty(&group->active_list)) {
423 		member = list_entry(group->active_list.next,
424 				    struct mcast_member, list);
425 		atomic_inc(&member->refcount);
426 		list_del_init(&member->list);
427 		adjust_membership(group, member->multicast.rec.join_state, -1);
428 		member->state = MCAST_ERROR;
429 		spin_unlock_irq(&group->lock);
430 
431 		ret = member->multicast.callback(-ENETRESET,
432 						 &member->multicast);
433 		deref_member(member);
434 		if (ret)
435 			ib_sa_free_multicast(&member->multicast);
436 		spin_lock_irq(&group->lock);
437 	}
438 
439 	group->rec.join_state = 0;
440 out:
441 	group->state = MCAST_BUSY;
442 	spin_unlock_irq(&group->lock);
443 }
444 
445 static void mcast_work_handler(struct work_struct *work)
446 {
447 	struct mcast_group *group;
448 	struct mcast_member *member;
449 	struct ib_sa_multicast *multicast;
450 	int status, ret;
451 	u8 join_state;
452 
453 	group = container_of(work, typeof(*group), work);
454 retest:
455 	spin_lock_irq(&group->lock);
456 	while (!list_empty(&group->pending_list) ||
457 	       (group->state != MCAST_BUSY)) {
458 
459 		if (group->state != MCAST_BUSY) {
460 			spin_unlock_irq(&group->lock);
461 			process_group_error(group);
462 			goto retest;
463 		}
464 
465 		member = list_entry(group->pending_list.next,
466 				    struct mcast_member, list);
467 		multicast = &member->multicast;
468 		join_state = multicast->rec.join_state;
469 		atomic_inc(&member->refcount);
470 
471 		if (join_state == (group->rec.join_state & join_state)) {
472 			status = cmp_rec(&group->rec, &multicast->rec,
473 					 multicast->comp_mask);
474 			if (!status)
475 				join_group(group, member, join_state);
476 			else
477 				list_del_init(&member->list);
478 			spin_unlock_irq(&group->lock);
479 			ret = multicast->callback(status, multicast);
480 		} else {
481 			spin_unlock_irq(&group->lock);
482 			status = send_join(group, member);
483 			if (!status) {
484 				deref_member(member);
485 				return;
486 			}
487 			ret = fail_join(group, member, status);
488 		}
489 
490 		deref_member(member);
491 		if (ret)
492 			ib_sa_free_multicast(&member->multicast);
493 		spin_lock_irq(&group->lock);
494 	}
495 
496 	join_state = get_leave_state(group);
497 	if (join_state) {
498 		group->rec.join_state &= ~join_state;
499 		spin_unlock_irq(&group->lock);
500 		if (send_leave(group, join_state))
501 			goto retest;
502 	} else {
503 		group->state = MCAST_IDLE;
504 		spin_unlock_irq(&group->lock);
505 		release_group(group);
506 	}
507 }
508 
509 /*
510  * Fail a join request if it is still active - at the head of the pending queue.
511  */
512 static void process_join_error(struct mcast_group *group, int status)
513 {
514 	struct mcast_member *member;
515 	int ret;
516 
517 	spin_lock_irq(&group->lock);
518 	member = list_entry(group->pending_list.next,
519 			    struct mcast_member, list);
520 	if (group->last_join == member) {
521 		atomic_inc(&member->refcount);
522 		list_del_init(&member->list);
523 		spin_unlock_irq(&group->lock);
524 		ret = member->multicast.callback(status, &member->multicast);
525 		deref_member(member);
526 		if (ret)
527 			ib_sa_free_multicast(&member->multicast);
528 	} else
529 		spin_unlock_irq(&group->lock);
530 }
531 
532 static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
533 			 void *context)
534 {
535 	struct mcast_group *group = context;
536 	u16 pkey_index = MCAST_INVALID_PKEY_INDEX;
537 
538 	if (status)
539 		process_join_error(group, status);
540 	else {
541 		int mgids_changed, is_mgid0;
542 		ib_find_pkey(group->port->dev->device, group->port->port_num,
543 			     be16_to_cpu(rec->pkey), &pkey_index);
544 
545 		spin_lock_irq(&group->port->lock);
546 		if (group->state == MCAST_BUSY &&
547 		    group->pkey_index == MCAST_INVALID_PKEY_INDEX)
548 			group->pkey_index = pkey_index;
549 		mgids_changed = memcmp(&rec->mgid, &group->rec.mgid,
550 				       sizeof(group->rec.mgid));
551 		group->rec = *rec;
552 		if (mgids_changed) {
553 			rb_erase(&group->node, &group->port->table);
554 			is_mgid0 = !memcmp(&mgid0, &group->rec.mgid,
555 					   sizeof(mgid0));
556 			mcast_insert(group->port, group, is_mgid0);
557 		}
558 		spin_unlock_irq(&group->port->lock);
559 	}
560 	mcast_work_handler(&group->work);
561 }
562 
563 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
564 			  void *context)
565 {
566 	struct mcast_group *group = context;
567 
568 	if (status && group->retries > 0 &&
569 	    !send_leave(group, group->leave_state))
570 		group->retries--;
571 	else
572 		mcast_work_handler(&group->work);
573 }
574 
575 static struct mcast_group *acquire_group(struct mcast_port *port,
576 					 union ib_gid *mgid, gfp_t gfp_mask)
577 {
578 	struct mcast_group *group, *cur_group;
579 	unsigned long flags;
580 	int is_mgid0;
581 
582 	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
583 	if (!is_mgid0) {
584 		spin_lock_irqsave(&port->lock, flags);
585 		group = mcast_find(port, mgid);
586 		if (group)
587 			goto found;
588 		spin_unlock_irqrestore(&port->lock, flags);
589 	}
590 
591 	group = kzalloc(sizeof *group, gfp_mask);
592 	if (!group)
593 		return NULL;
594 
595 	group->retries = 3;
596 	group->port = port;
597 	group->rec.mgid = *mgid;
598 	group->pkey_index = MCAST_INVALID_PKEY_INDEX;
599 	INIT_LIST_HEAD(&group->pending_list);
600 	INIT_LIST_HEAD(&group->active_list);
601 	INIT_WORK(&group->work, mcast_work_handler);
602 	spin_lock_init(&group->lock);
603 
604 	spin_lock_irqsave(&port->lock, flags);
605 	cur_group = mcast_insert(port, group, is_mgid0);
606 	if (cur_group) {
607 		kfree(group);
608 		group = cur_group;
609 	} else
610 		atomic_inc(&port->refcount);
611 found:
612 	atomic_inc(&group->refcount);
613 	spin_unlock_irqrestore(&port->lock, flags);
614 	return group;
615 }
616 
617 /*
618  * We serialize all join requests to a single group to make our lives much
619  * easier.  Otherwise, two users could try to join the same group
620  * simultaneously, with different configurations, one could leave while the
621  * join is in progress, etc., which makes locking around error recovery
622  * difficult.
623  */
624 struct ib_sa_multicast *
625 ib_sa_join_multicast(struct ib_sa_client *client,
626 		     struct ib_device *device, u8 port_num,
627 		     struct ib_sa_mcmember_rec *rec,
628 		     ib_sa_comp_mask comp_mask, gfp_t gfp_mask,
629 		     int (*callback)(int status,
630 				     struct ib_sa_multicast *multicast),
631 		     void *context)
632 {
633 	struct mcast_device *dev;
634 	struct mcast_member *member;
635 	struct ib_sa_multicast *multicast;
636 	int ret;
637 
638 	dev = ib_get_client_data(device, &mcast_client);
639 	if (!dev)
640 		return ERR_PTR(-ENODEV);
641 
642 	member = kmalloc(sizeof *member, gfp_mask);
643 	if (!member)
644 		return ERR_PTR(-ENOMEM);
645 
646 	ib_sa_client_get(client);
647 	member->client = client;
648 	member->multicast.rec = *rec;
649 	member->multicast.comp_mask = comp_mask;
650 	member->multicast.callback = callback;
651 	member->multicast.context = context;
652 	init_completion(&member->comp);
653 	atomic_set(&member->refcount, 1);
654 	member->state = MCAST_JOINING;
655 
656 	member->group = acquire_group(&dev->port[port_num - dev->start_port],
657 				      &rec->mgid, gfp_mask);
658 	if (!member->group) {
659 		ret = -ENOMEM;
660 		goto err;
661 	}
662 
663 	/*
664 	 * The user will get the multicast structure in their callback.  They
665 	 * could then free the multicast structure before we can return from
666 	 * this routine.  So we save the pointer to return before queuing
667 	 * any callback.
668 	 */
669 	multicast = &member->multicast;
670 	queue_join(member);
671 	return multicast;
672 
673 err:
674 	ib_sa_client_put(client);
675 	kfree(member);
676 	return ERR_PTR(ret);
677 }
678 EXPORT_SYMBOL(ib_sa_join_multicast);
679 
680 void ib_sa_free_multicast(struct ib_sa_multicast *multicast)
681 {
682 	struct mcast_member *member;
683 	struct mcast_group *group;
684 
685 	member = container_of(multicast, struct mcast_member, multicast);
686 	group = member->group;
687 
688 	spin_lock_irq(&group->lock);
689 	if (member->state == MCAST_MEMBER)
690 		adjust_membership(group, multicast->rec.join_state, -1);
691 
692 	list_del_init(&member->list);
693 
694 	if (group->state == MCAST_IDLE) {
695 		group->state = MCAST_BUSY;
696 		spin_unlock_irq(&group->lock);
697 		/* Continue to hold reference on group until callback */
698 		queue_work(mcast_wq, &group->work);
699 	} else {
700 		spin_unlock_irq(&group->lock);
701 		release_group(group);
702 	}
703 
704 	deref_member(member);
705 	wait_for_completion(&member->comp);
706 	ib_sa_client_put(member->client);
707 	kfree(member);
708 }
709 EXPORT_SYMBOL(ib_sa_free_multicast);
710 
711 int ib_sa_get_mcmember_rec(struct ib_device *device, u8 port_num,
712 			   union ib_gid *mgid, struct ib_sa_mcmember_rec *rec)
713 {
714 	struct mcast_device *dev;
715 	struct mcast_port *port;
716 	struct mcast_group *group;
717 	unsigned long flags;
718 	int ret = 0;
719 
720 	dev = ib_get_client_data(device, &mcast_client);
721 	if (!dev)
722 		return -ENODEV;
723 
724 	port = &dev->port[port_num - dev->start_port];
725 	spin_lock_irqsave(&port->lock, flags);
726 	group = mcast_find(port, mgid);
727 	if (group)
728 		*rec = group->rec;
729 	else
730 		ret = -EADDRNOTAVAIL;
731 	spin_unlock_irqrestore(&port->lock, flags);
732 
733 	return ret;
734 }
735 EXPORT_SYMBOL(ib_sa_get_mcmember_rec);
736 
737 int ib_init_ah_from_mcmember(struct ib_device *device, u8 port_num,
738 			     struct ib_sa_mcmember_rec *rec,
739 			     struct net_device *ndev,
740 			     enum ib_gid_type gid_type,
741 			     struct ib_ah_attr *ah_attr)
742 {
743 	int ret;
744 	u16 gid_index;
745 	u8 p;
746 
747 	if (rdma_protocol_roce(device, port_num)) {
748 		ret = ib_find_cached_gid_by_port(device, &rec->port_gid,
749 						 gid_type, port_num,
750 						 ndev,
751 						 &gid_index);
752 	} else if (rdma_protocol_ib(device, port_num)) {
753 		ret = ib_find_cached_gid(device, &rec->port_gid,
754 					 IB_GID_TYPE_IB, NULL, &p,
755 					 &gid_index);
756 	} else {
757 		ret = -EINVAL;
758 	}
759 
760 	if (ret)
761 		return ret;
762 
763 	memset(ah_attr, 0, sizeof *ah_attr);
764 	ah_attr->dlid = be16_to_cpu(rec->mlid);
765 	ah_attr->sl = rec->sl;
766 	ah_attr->port_num = port_num;
767 	ah_attr->static_rate = rec->rate;
768 
769 	ah_attr->ah_flags = IB_AH_GRH;
770 	ah_attr->grh.dgid = rec->mgid;
771 
772 	ah_attr->grh.sgid_index = (u8) gid_index;
773 	ah_attr->grh.flow_label = be32_to_cpu(rec->flow_label);
774 	ah_attr->grh.hop_limit = rec->hop_limit;
775 	ah_attr->grh.traffic_class = rec->traffic_class;
776 
777 	return 0;
778 }
779 EXPORT_SYMBOL(ib_init_ah_from_mcmember);
780 
781 static void mcast_groups_event(struct mcast_port *port,
782 			       enum mcast_group_state state)
783 {
784 	struct mcast_group *group;
785 	struct rb_node *node;
786 	unsigned long flags;
787 
788 	spin_lock_irqsave(&port->lock, flags);
789 	for (node = rb_first(&port->table); node; node = rb_next(node)) {
790 		group = rb_entry(node, struct mcast_group, node);
791 		spin_lock(&group->lock);
792 		if (group->state == MCAST_IDLE) {
793 			atomic_inc(&group->refcount);
794 			queue_work(mcast_wq, &group->work);
795 		}
796 		if (group->state != MCAST_GROUP_ERROR)
797 			group->state = state;
798 		spin_unlock(&group->lock);
799 	}
800 	spin_unlock_irqrestore(&port->lock, flags);
801 }
802 
803 static void mcast_event_handler(struct ib_event_handler *handler,
804 				struct ib_event *event)
805 {
806 	struct mcast_device *dev;
807 	int index;
808 
809 	dev = container_of(handler, struct mcast_device, event_handler);
810 	if (!rdma_cap_ib_mcast(dev->device, event->element.port_num))
811 		return;
812 
813 	index = event->element.port_num - dev->start_port;
814 
815 	switch (event->event) {
816 	case IB_EVENT_PORT_ERR:
817 	case IB_EVENT_LID_CHANGE:
818 	case IB_EVENT_SM_CHANGE:
819 	case IB_EVENT_CLIENT_REREGISTER:
820 		mcast_groups_event(&dev->port[index], MCAST_GROUP_ERROR);
821 		break;
822 	case IB_EVENT_PKEY_CHANGE:
823 		mcast_groups_event(&dev->port[index], MCAST_PKEY_EVENT);
824 		break;
825 	default:
826 		break;
827 	}
828 }
829 
830 static void mcast_add_one(struct ib_device *device)
831 {
832 	struct mcast_device *dev;
833 	struct mcast_port *port;
834 	int i;
835 	int count = 0;
836 
837 	dev = kmalloc(sizeof *dev + device->phys_port_cnt * sizeof *port,
838 		      GFP_KERNEL);
839 	if (!dev)
840 		return;
841 
842 	dev->start_port = rdma_start_port(device);
843 	dev->end_port = rdma_end_port(device);
844 
845 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
846 		if (!rdma_cap_ib_mcast(device, dev->start_port + i))
847 			continue;
848 		port = &dev->port[i];
849 		port->dev = dev;
850 		port->port_num = dev->start_port + i;
851 		spin_lock_init(&port->lock);
852 		port->table = RB_ROOT;
853 		init_completion(&port->comp);
854 		atomic_set(&port->refcount, 1);
855 		++count;
856 	}
857 
858 	if (!count) {
859 		kfree(dev);
860 		return;
861 	}
862 
863 	dev->device = device;
864 	ib_set_client_data(device, &mcast_client, dev);
865 
866 	INIT_IB_EVENT_HANDLER(&dev->event_handler, device, mcast_event_handler);
867 	ib_register_event_handler(&dev->event_handler);
868 }
869 
870 static void mcast_remove_one(struct ib_device *device, void *client_data)
871 {
872 	struct mcast_device *dev = client_data;
873 	struct mcast_port *port;
874 	int i;
875 
876 	if (!dev)
877 		return;
878 
879 	ib_unregister_event_handler(&dev->event_handler);
880 	flush_workqueue(mcast_wq);
881 
882 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
883 		if (rdma_cap_ib_mcast(device, dev->start_port + i)) {
884 			port = &dev->port[i];
885 			deref_port(port);
886 			wait_for_completion(&port->comp);
887 		}
888 	}
889 
890 	kfree(dev);
891 }
892 
893 int mcast_init(void)
894 {
895 	int ret;
896 
897 	mcast_wq = create_singlethread_workqueue("ib_mcast");
898 	if (!mcast_wq)
899 		return -ENOMEM;
900 
901 	ib_sa_register_client(&sa_client);
902 
903 	ret = ib_register_client(&mcast_client);
904 	if (ret)
905 		goto err;
906 	return 0;
907 
908 err:
909 	ib_sa_unregister_client(&sa_client);
910 	destroy_workqueue(mcast_wq);
911 	return ret;
912 }
913 
914 void mcast_cleanup(void)
915 {
916 	ib_unregister_client(&mcast_client);
917 	ib_sa_unregister_client(&sa_client);
918 	destroy_workqueue(mcast_wq);
919 }
920