xref: /NextBSD/sys/ofed/drivers/infiniband/core/multicast.c (revision 287e3b14e9552995def1802ec9c5034f4adf28ec)
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/module.h>
38 #include <linux/slab.h>
39 #include <linux/bitops.h>
40 #include <linux/random.h>
41 #include <linux/moduleparam.h>
42 #include <linux/rbtree.h>
43 
44 #include <rdma/ib_cache.h>
45 #include "sa.h"
46 
47 static int mcast_leave_retries = 3;
48 
49 /*static const struct kernel_param_ops retry_ops = {
50 	.set = param_set_int,
51 	.get = param_get_int,
52 };
53 
54 module_param_cb(mcast_leave_retries, &retry_ops, &mcast_leave_retries, 0644);
55 MODULE_PARM_DESC(mcast_leave_retries, "Number of retries for multicast leave "
56 				      "requests before giving up (default: 3)");
57 */
58 static void mcast_add_one(struct ib_device *device);
59 static void mcast_remove_one(struct ib_device *device);
60 
61 static struct ib_client mcast_client = {
62 	.name   = "ib_multicast",
63 	.add    = mcast_add_one,
64 	.remove = mcast_remove_one
65 };
66 
67 static struct ib_sa_client	sa_client;
68 static struct workqueue_struct	*mcast_wq;
69 static union ib_gid mgid0;
70 
71 struct mcast_device;
72 
73 struct mcast_port {
74 	struct mcast_device	*dev;
75 	spinlock_t		lock;
76 	struct rb_root		table;
77 	atomic_t		refcount;
78 	struct completion	comp;
79 	u8			port_num;
80 };
81 
82 struct mcast_device {
83 	struct ib_device	*device;
84 	struct ib_event_handler	event_handler;
85 	int			start_port;
86 	int			end_port;
87 	struct mcast_port	port[0];
88 };
89 
90 enum mcast_state {
91 	MCAST_JOINING,
92 	MCAST_MEMBER,
93 	MCAST_ERROR,
94 };
95 
96 enum mcast_group_state {
97 	MCAST_IDLE,
98 	MCAST_BUSY,
99 	MCAST_GROUP_ERROR,
100 	MCAST_PKEY_EVENT
101 };
102 
103 enum {
104 	MCAST_INVALID_PKEY_INDEX = 0xFFFF
105 };
106 
107 struct mcast_member;
108 
109 struct mcast_group {
110 	struct ib_sa_mcmember_rec rec;
111 	struct rb_node		node;
112 	struct mcast_port	*port;
113 	spinlock_t		lock;
114 	struct work_struct	work;
115 	struct list_head	pending_list;
116 	struct list_head	active_list;
117 	struct mcast_member	*last_join;
118 	int			members[3];
119 	atomic_t		refcount;
120 	enum mcast_group_state	state;
121 	struct ib_sa_query	*query;
122 	int			query_id;
123 	u16			pkey_index;
124 	u8			leave_state;
125 	int			retries;
126 };
127 
128 struct mcast_member {
129 	struct ib_sa_multicast	multicast;
130 	struct ib_sa_client	*client;
131 	struct mcast_group	*group;
132 	struct list_head	list;
133 	enum mcast_state	state;
134 	atomic_t		refcount;
135 	struct completion	comp;
136 };
137 
138 static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
139 			 void *context);
140 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
141 			  void *context);
142 
mcast_find(struct mcast_port * port,union ib_gid * mgid)143 static struct mcast_group *mcast_find(struct mcast_port *port,
144 				      union ib_gid *mgid)
145 {
146 	struct rb_node *node = port->table.rb_node;
147 	struct mcast_group *group;
148 	int ret;
149 
150 	while (node) {
151 		group = rb_entry(node, struct mcast_group, node);
152 		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
153 		if (!ret)
154 			return group;
155 
156 		if (ret < 0)
157 			node = node->rb_left;
158 		else
159 			node = node->rb_right;
160 	}
161 	return NULL;
162 }
163 
mcast_insert(struct mcast_port * port,struct mcast_group * group,int allow_duplicates)164 static struct mcast_group *mcast_insert(struct mcast_port *port,
165 					struct mcast_group *group,
166 					int allow_duplicates)
167 {
168 	struct rb_node **link = &port->table.rb_node;
169 	struct rb_node *parent = NULL;
170 	struct mcast_group *cur_group;
171 	int ret;
172 
173 	while (*link) {
174 		parent = *link;
175 		cur_group = rb_entry(parent, struct mcast_group, node);
176 
177 		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
178 			     sizeof group->rec.mgid);
179 		if (ret < 0)
180 			link = &(*link)->rb_left;
181 		else if (ret > 0)
182 			link = &(*link)->rb_right;
183 		else if (allow_duplicates)
184 			link = &(*link)->rb_left;
185 		else
186 			return cur_group;
187 	}
188 	rb_link_node(&group->node, parent, link);
189 	rb_insert_color(&group->node, &port->table);
190 	return NULL;
191 }
192 
deref_port(struct mcast_port * port)193 static void deref_port(struct mcast_port *port)
194 {
195 	if (atomic_dec_and_test(&port->refcount))
196 		complete(&port->comp);
197 }
198 
release_group(struct mcast_group * group)199 static void release_group(struct mcast_group *group)
200 {
201 	struct mcast_port *port = group->port;
202 	unsigned long flags;
203 
204 	spin_lock_irqsave(&port->lock, flags);
205 	if (atomic_dec_and_test(&group->refcount)) {
206 		rb_erase(&group->node, &port->table);
207 		spin_unlock_irqrestore(&port->lock, flags);
208 		kfree(group);
209 		deref_port(port);
210 	} else
211 		spin_unlock_irqrestore(&port->lock, flags);
212 }
213 
deref_member(struct mcast_member * member)214 static void deref_member(struct mcast_member *member)
215 {
216 	if (atomic_dec_and_test(&member->refcount))
217 		complete(&member->comp);
218 }
219 
queue_join(struct mcast_member * member)220 static void queue_join(struct mcast_member *member)
221 {
222 	struct mcast_group *group = member->group;
223 	unsigned long flags;
224 
225 	spin_lock_irqsave(&group->lock, flags);
226 	list_add_tail(&member->list, &group->pending_list);
227 	if (group->state == MCAST_IDLE) {
228 		group->state = MCAST_BUSY;
229 		atomic_inc(&group->refcount);
230 		queue_work(mcast_wq, &group->work);
231 	}
232 	spin_unlock_irqrestore(&group->lock, flags);
233 }
234 
235 /*
236  * A multicast group has three types of members: full member, non member, and
237  * send only member.  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  */
adjust_membership(struct mcast_group * group,u8 join_state,int inc)241 static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
242 {
243 	int i;
244 
245 	for (i = 0; i < 3; 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  */
get_leave_state(struct mcast_group * group)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 < 3; i++)
262 		if (!group->members[i])
263 			leave_state |= (0x1 << i);
264 
265 	return leave_state & group->rec.join_state;
266 }
267 
check_selector(ib_sa_comp_mask comp_mask,ib_sa_comp_mask selector_mask,ib_sa_comp_mask value_mask,u8 selector,u8 src_value,u8 dst_value)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 
cmp_rec(struct ib_sa_mcmember_rec * src,struct ib_sa_mcmember_rec * dst,ib_sa_comp_mask comp_mask)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 
send_join(struct mcast_group * group,struct mcast_member * member)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 
send_leave(struct mcast_group * group,u8 leave_state)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 
join_group(struct mcast_group * group,struct mcast_member * member,u8 join_state)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 
fail_join(struct mcast_group * group,struct mcast_member * member,int status)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 
process_group_error(struct mcast_group * group)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 
mcast_work_handler(struct work_struct * work)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  */
process_join_error(struct mcast_group * group,int status)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 
join_handler(int status,struct ib_sa_mcmember_rec * rec,void * context)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 		ib_find_pkey(group->port->dev->device, group->port->port_num,
542 			     be16_to_cpu(rec->pkey), &pkey_index);
543 
544 		spin_lock_irq(&group->port->lock);
545 		group->rec = *rec;
546 		if (group->state == MCAST_BUSY &&
547 		    group->pkey_index == MCAST_INVALID_PKEY_INDEX)
548 			group->pkey_index = pkey_index;
549 		if (!memcmp(&mgid0, &group->rec.mgid, sizeof mgid0)) {
550 			rb_erase(&group->node, &group->port->table);
551 			mcast_insert(group->port, group, 1);
552 		}
553 		spin_unlock_irq(&group->port->lock);
554 	}
555 	mcast_work_handler(&group->work);
556 }
557 
leave_handler(int status,struct ib_sa_mcmember_rec * rec,void * context)558 static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
559 			  void *context)
560 {
561 	struct mcast_group *group = context;
562 
563 	if (status && group->retries > 0 &&
564 	    !send_leave(group, group->leave_state))
565 		group->retries--;
566 	else {
567 		if (status && group->retries <= 0)
568 			printk(KERN_WARNING "reached max retry count. "
569 			       "status=%d. Giving up\n", status);
570 		mcast_work_handler(&group->work);
571 	}
572 }
573 
acquire_group(struct mcast_port * port,union ib_gid * mgid,gfp_t gfp_mask)574 static struct mcast_group *acquire_group(struct mcast_port *port,
575 					 union ib_gid *mgid, gfp_t gfp_mask)
576 {
577 	struct mcast_group *group, *cur_group;
578 	unsigned long flags;
579 	int is_mgid0;
580 
581 	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
582 	if (!is_mgid0) {
583 		spin_lock_irqsave(&port->lock, flags);
584 		group = mcast_find(port, mgid);
585 		if (group)
586 			goto found;
587 		spin_unlock_irqrestore(&port->lock, flags);
588 	}
589 
590 	group = kzalloc(sizeof *group, gfp_mask);
591 	if (!group)
592 		return NULL;
593 
594 	group->retries = mcast_leave_retries;
595 	group->port = port;
596 	group->rec.mgid = *mgid;
597 	group->pkey_index = MCAST_INVALID_PKEY_INDEX;
598 	INIT_LIST_HEAD(&group->pending_list);
599 	INIT_LIST_HEAD(&group->active_list);
600 	INIT_WORK(&group->work, mcast_work_handler);
601 	spin_lock_init(&group->lock);
602 
603 	spin_lock_irqsave(&port->lock, flags);
604 	cur_group = mcast_insert(port, group, is_mgid0);
605 	if (cur_group) {
606 		kfree(group);
607 		group = cur_group;
608 	} else
609 		atomic_inc(&port->refcount);
610 found:
611 	atomic_inc(&group->refcount);
612 	spin_unlock_irqrestore(&port->lock, flags);
613 	return group;
614 }
615 
616 /*
617  * We serialize all join requests to a single group to make our lives much
618  * easier.  Otherwise, two users could try to join the same group
619  * simultaneously, with different configurations, one could leave while the
620  * join is in progress, etc., which makes locking around error recovery
621  * difficult.
622  */
623 struct ib_sa_multicast *
ib_sa_join_multicast(struct ib_sa_client * client,struct ib_device * device,u8 port_num,struct ib_sa_mcmember_rec * rec,ib_sa_comp_mask comp_mask,gfp_t gfp_mask,int (* callback)(int status,struct ib_sa_multicast * multicast),void * context)624 ib_sa_join_multicast(struct ib_sa_client *client,
625 		     struct ib_device *device, u8 port_num,
626 		     struct ib_sa_mcmember_rec *rec,
627 		     ib_sa_comp_mask comp_mask, gfp_t gfp_mask,
628 		     int (*callback)(int status,
629 				     struct ib_sa_multicast *multicast),
630 		     void *context)
631 {
632 	struct mcast_device *dev;
633 	struct mcast_member *member;
634 	struct ib_sa_multicast *multicast;
635 	int ret;
636 
637 	dev = ib_get_client_data(device, &mcast_client);
638 	if (!dev)
639 		return ERR_PTR(-ENODEV);
640 
641 	member = kmalloc(sizeof *member, gfp_mask);
642 	if (!member)
643 		return ERR_PTR(-ENOMEM);
644 
645 	ib_sa_client_get(client);
646 	member->client = client;
647 	member->multicast.rec = *rec;
648 	member->multicast.comp_mask = comp_mask;
649 	member->multicast.callback = callback;
650 	member->multicast.context = context;
651 	init_completion(&member->comp);
652 	atomic_set(&member->refcount, 1);
653 	member->state = MCAST_JOINING;
654 
655 	member->group = acquire_group(&dev->port[port_num - dev->start_port],
656 				      &rec->mgid, gfp_mask);
657 	if (!member->group) {
658 		ret = -ENOMEM;
659 		goto err;
660 	}
661 
662 	/*
663 	 * The user will get the multicast structure in their callback.  They
664 	 * could then free the multicast structure before we can return from
665 	 * this routine.  So we save the pointer to return before queuing
666 	 * any callback.
667 	 */
668 	multicast = &member->multicast;
669 	queue_join(member);
670 	return multicast;
671 
672 err:
673 	ib_sa_client_put(client);
674 	kfree(member);
675 	return ERR_PTR(ret);
676 }
677 EXPORT_SYMBOL(ib_sa_join_multicast);
678 
ib_sa_free_multicast(struct ib_sa_multicast * multicast)679 void ib_sa_free_multicast(struct ib_sa_multicast *multicast)
680 {
681 	struct mcast_member *member;
682 	struct mcast_group *group;
683 
684 	member = container_of(multicast, struct mcast_member, multicast);
685 	group = member->group;
686 
687 	spin_lock_irq(&group->lock);
688 	if (member->state == MCAST_MEMBER)
689 		adjust_membership(group, multicast->rec.join_state, -1);
690 
691 	list_del_init(&member->list);
692 
693 	if (group->state == MCAST_IDLE) {
694 		group->state = MCAST_BUSY;
695 		spin_unlock_irq(&group->lock);
696 		/* Continue to hold reference on group until callback */
697 		queue_work(mcast_wq, &group->work);
698 	} else {
699 		spin_unlock_irq(&group->lock);
700 		release_group(group);
701 	}
702 
703 	deref_member(member);
704 	wait_for_completion(&member->comp);
705 	ib_sa_client_put(member->client);
706 	kfree(member);
707 }
708 EXPORT_SYMBOL(ib_sa_free_multicast);
709 
ib_sa_get_mcmember_rec(struct ib_device * device,u8 port_num,union ib_gid * mgid,struct ib_sa_mcmember_rec * rec)710 int ib_sa_get_mcmember_rec(struct ib_device *device, u8 port_num,
711 			   union ib_gid *mgid, struct ib_sa_mcmember_rec *rec)
712 {
713 	struct mcast_device *dev;
714 	struct mcast_port *port;
715 	struct mcast_group *group;
716 	unsigned long flags;
717 	int ret = 0;
718 
719 	dev = ib_get_client_data(device, &mcast_client);
720 	if (!dev)
721 		return -ENODEV;
722 
723 	port = &dev->port[port_num - dev->start_port];
724 	spin_lock_irqsave(&port->lock, flags);
725 	group = mcast_find(port, mgid);
726 	if (group)
727 		*rec = group->rec;
728 	else
729 		ret = -EADDRNOTAVAIL;
730 	spin_unlock_irqrestore(&port->lock, flags);
731 
732 	return ret;
733 }
734 EXPORT_SYMBOL(ib_sa_get_mcmember_rec);
735 
ib_init_ah_from_mcmember(struct ib_device * device,u8 port_num,struct ib_sa_mcmember_rec * rec,struct ib_ah_attr * ah_attr)736 int ib_init_ah_from_mcmember(struct ib_device *device, u8 port_num,
737 			     struct ib_sa_mcmember_rec *rec,
738 			     struct ib_ah_attr *ah_attr)
739 {
740 	int ret;
741 	u16 gid_index;
742 	u8 p;
743 
744 	ret = ib_find_cached_gid(device, &rec->port_gid, &p, &gid_index);
745 	if (ret)
746 		return ret;
747 
748 	memset(ah_attr, 0, sizeof *ah_attr);
749 	ah_attr->dlid = be16_to_cpu(rec->mlid);
750 	ah_attr->sl = rec->sl;
751 	ah_attr->port_num = port_num;
752 	ah_attr->static_rate = rec->rate;
753 
754 	ah_attr->ah_flags = IB_AH_GRH;
755 	ah_attr->grh.dgid = rec->mgid;
756 
757 	ah_attr->grh.sgid_index = (u8) gid_index;
758 	ah_attr->grh.flow_label = be32_to_cpu(rec->flow_label);
759 	ah_attr->grh.hop_limit = rec->hop_limit;
760 	ah_attr->grh.traffic_class = rec->traffic_class;
761 
762 	return 0;
763 }
764 EXPORT_SYMBOL(ib_init_ah_from_mcmember);
765 
mcast_groups_event(struct mcast_port * port,enum mcast_group_state state)766 static void mcast_groups_event(struct mcast_port *port,
767 			       enum mcast_group_state state)
768 {
769 	struct mcast_group *group;
770 	struct rb_node *node;
771 	unsigned long flags;
772 
773 	spin_lock_irqsave(&port->lock, flags);
774 	for (node = rb_first(&port->table); node; node = rb_next(node)) {
775 		group = rb_entry(node, struct mcast_group, node);
776 		spin_lock(&group->lock);
777 		if (group->state == MCAST_IDLE) {
778 			atomic_inc(&group->refcount);
779 			queue_work(mcast_wq, &group->work);
780 		}
781 		if (group->state != MCAST_GROUP_ERROR)
782 			group->state = state;
783 		spin_unlock(&group->lock);
784 	}
785 	spin_unlock_irqrestore(&port->lock, flags);
786 }
787 
mcast_event_handler(struct ib_event_handler * handler,struct ib_event * event)788 static void mcast_event_handler(struct ib_event_handler *handler,
789 				struct ib_event *event)
790 {
791 	struct mcast_device *dev;
792 	int index;
793 
794 	dev = container_of(handler, struct mcast_device, event_handler);
795 	if (rdma_port_get_link_layer(dev->device, event->element.port_num) !=
796 	    IB_LINK_LAYER_INFINIBAND)
797 		return;
798 
799 	index = event->element.port_num - dev->start_port;
800 
801 	switch (event->event) {
802 	case IB_EVENT_PORT_ERR:
803 	case IB_EVENT_LID_CHANGE:
804 	case IB_EVENT_CLIENT_REREGISTER:
805 		mcast_groups_event(&dev->port[index], MCAST_GROUP_ERROR);
806 		break;
807 	case IB_EVENT_PKEY_CHANGE:
808 		mcast_groups_event(&dev->port[index], MCAST_PKEY_EVENT);
809 		break;
810 	default:
811 		break;
812 	}
813 }
814 
mcast_add_one(struct ib_device * device)815 static void mcast_add_one(struct ib_device *device)
816 {
817 	struct mcast_device *dev;
818 	struct mcast_port *port;
819 	int i;
820 	int count = 0;
821 
822 	if (rdma_node_get_transport(device->node_type) != RDMA_TRANSPORT_IB)
823 		return;
824 
825 	dev = kmalloc(sizeof *dev + device->phys_port_cnt * sizeof *port,
826 		      GFP_KERNEL);
827 	if (!dev)
828 		return;
829 
830 	if (device->node_type == RDMA_NODE_IB_SWITCH)
831 		dev->start_port = dev->end_port = 0;
832 	else {
833 		dev->start_port = 1;
834 		dev->end_port = device->phys_port_cnt;
835 	}
836 
837 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
838 		if (rdma_port_get_link_layer(device, dev->start_port + i) !=
839 		    IB_LINK_LAYER_INFINIBAND)
840 			continue;
841 		port = &dev->port[i];
842 		port->dev = dev;
843 		port->port_num = dev->start_port + i;
844 		spin_lock_init(&port->lock);
845 		port->table = RB_ROOT;
846 		init_completion(&port->comp);
847 		atomic_set(&port->refcount, 1);
848 		++count;
849 	}
850 
851 	if (!count) {
852 		kfree(dev);
853 		return;
854 	}
855 
856 	dev->device = device;
857 	ib_set_client_data(device, &mcast_client, dev);
858 
859 	INIT_IB_EVENT_HANDLER(&dev->event_handler, device, mcast_event_handler);
860 	ib_register_event_handler(&dev->event_handler);
861 }
862 
mcast_remove_one(struct ib_device * device)863 static void mcast_remove_one(struct ib_device *device)
864 {
865 	struct mcast_device *dev;
866 	struct mcast_port *port;
867 	int i;
868 
869 	dev = ib_get_client_data(device, &mcast_client);
870 	if (!dev)
871 		return;
872 
873 	ib_unregister_event_handler(&dev->event_handler);
874 	flush_workqueue(mcast_wq);
875 
876 	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
877 		if (rdma_port_get_link_layer(device, dev->start_port + i) ==
878 		    IB_LINK_LAYER_INFINIBAND) {
879 			port = &dev->port[i];
880 			deref_port(port);
881 			wait_for_completion(&port->comp);
882 		}
883 	}
884 
885 	kfree(dev);
886 }
887 
mcast_init(void)888 int mcast_init(void)
889 {
890 	int ret;
891 
892 	mcast_wq = create_singlethread_workqueue("ib_mcast");
893 	if (!mcast_wq)
894 		return -ENOMEM;
895 
896 	ib_sa_register_client(&sa_client);
897 
898 	ret = ib_register_client(&mcast_client);
899 	if (ret)
900 		goto err;
901 	return 0;
902 
903 err:
904 	ib_sa_unregister_client(&sa_client);
905 	destroy_workqueue(mcast_wq);
906 	return ret;
907 }
908 
mcast_cleanup(void)909 void mcast_cleanup(void)
910 {
911 	ib_unregister_client(&mcast_client);
912 	ib_sa_unregister_client(&sa_client);
913 	destroy_workqueue(mcast_wq);
914 }
915