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
45static int mcast_add_one(struct ib_device *device);
46static void mcast_remove_one(struct ib_device *device, void *client_data);
47
48static struct ib_client mcast_client = {
49	.name   = "ib_multicast",
50	.add    = mcast_add_one,
51	.remove = mcast_remove_one
52};
53
54static struct ib_sa_client	sa_client;
55static struct workqueue_struct	*mcast_wq;
56static union ib_gid mgid0;
57
58struct mcast_device;
59
60struct mcast_port {
61	struct mcast_device	*dev;
62	spinlock_t		lock;
63	struct rb_root		table;
64	refcount_t		refcount;
65	struct completion	comp;
66	u32			port_num;
67};
68
69struct 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[];
75};
76
77enum mcast_state {
78	MCAST_JOINING,
79	MCAST_MEMBER,
80	MCAST_ERROR,
81};
82
83enum mcast_group_state {
84	MCAST_IDLE,
85	MCAST_BUSY,
86	MCAST_GROUP_ERROR,
87	MCAST_PKEY_EVENT
88};
89
90enum {
91	MCAST_INVALID_PKEY_INDEX = 0xFFFF
92};
93
94struct mcast_member;
95
96struct mcast_group {
97	struct ib_sa_mcmember_rec rec;
98	struct rb_node		node;
99	struct mcast_port	*port;
100	spinlock_t		lock;
101	struct work_struct	work;
102	struct list_head	pending_list;
103	struct list_head	active_list;
104	struct mcast_member	*last_join;
105	int			members[NUM_JOIN_MEMBERSHIP_TYPES];
106	atomic_t		refcount;
107	enum mcast_group_state	state;
108	struct ib_sa_query	*query;
109	u16			pkey_index;
110	u8			leave_state;
111	int			retries;
112};
113
114struct mcast_member {
115	struct ib_sa_multicast	multicast;
116	struct ib_sa_client	*client;
117	struct mcast_group	*group;
118	struct list_head	list;
119	enum mcast_state	state;
120	refcount_t		refcount;
121	struct completion	comp;
122};
123
124static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
125			 void *context);
126static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
127			  void *context);
128
129static struct mcast_group *mcast_find(struct mcast_port *port,
130				      union ib_gid *mgid)
131{
132	struct rb_node *node = port->table.rb_node;
133	struct mcast_group *group;
134	int ret;
135
136	while (node) {
137		group = rb_entry(node, struct mcast_group, node);
138		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
139		if (!ret)
140			return group;
141
142		if (ret < 0)
143			node = node->rb_left;
144		else
145			node = node->rb_right;
146	}
147	return NULL;
148}
149
150static struct mcast_group *mcast_insert(struct mcast_port *port,
151					struct mcast_group *group,
152					int allow_duplicates)
153{
154	struct rb_node **link = &port->table.rb_node;
155	struct rb_node *parent = NULL;
156	struct mcast_group *cur_group;
157	int ret;
158
159	while (*link) {
160		parent = *link;
161		cur_group = rb_entry(parent, struct mcast_group, node);
162
163		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
164			     sizeof group->rec.mgid);
165		if (ret < 0)
166			link = &(*link)->rb_left;
167		else if (ret > 0)
168			link = &(*link)->rb_right;
169		else if (allow_duplicates)
170			link = &(*link)->rb_left;
171		else
172			return cur_group;
173	}
174	rb_link_node(&group->node, parent, link);
175	rb_insert_color(&group->node, &port->table);
176	return NULL;
177}
178
179static void deref_port(struct mcast_port *port)
180{
181	if (refcount_dec_and_test(&port->refcount))
182		complete(&port->comp);
183}
184
185static void release_group(struct mcast_group *group)
186{
187	struct mcast_port *port = group->port;
188	unsigned long flags;
189
190	spin_lock_irqsave(&port->lock, flags);
191	if (atomic_dec_and_test(&group->refcount)) {
192		rb_erase(&group->node, &port->table);
193		spin_unlock_irqrestore(&port->lock, flags);
194		kfree(group);
195		deref_port(port);
196	} else
197		spin_unlock_irqrestore(&port->lock, flags);
198}
199
200static void deref_member(struct mcast_member *member)
201{
202	if (refcount_dec_and_test(&member->refcount))
203		complete(&member->comp);
204}
205
206static void queue_join(struct mcast_member *member)
207{
208	struct mcast_group *group = member->group;
209	unsigned long flags;
210
211	spin_lock_irqsave(&group->lock, flags);
212	list_add_tail(&member->list, &group->pending_list);
213	if (group->state == MCAST_IDLE) {
214		group->state = MCAST_BUSY;
215		atomic_inc(&group->refcount);
216		queue_work(mcast_wq, &group->work);
217	}
218	spin_unlock_irqrestore(&group->lock, flags);
219}
220
221/*
222 * A multicast group has four types of members: full member, non member,
223 * sendonly non member and sendonly full member.
224 * We need to keep track of the number of members of each
225 * type based on their join state.  Adjust the number of members the belong to
226 * the specified join states.
227 */
228static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
229{
230	int i;
231
232	for (i = 0; i < NUM_JOIN_MEMBERSHIP_TYPES; i++, join_state >>= 1)
233		if (join_state & 0x1)
234			group->members[i] += inc;
235}
236
237/*
238 * If a multicast group has zero members left for a particular join state, but
239 * the group is still a member with the SA, we need to leave that join state.
240 * Determine which join states we still belong to, but that do not have any
241 * active members.
242 */
243static u8 get_leave_state(struct mcast_group *group)
244{
245	u8 leave_state = 0;
246	int i;
247
248	for (i = 0; i < NUM_JOIN_MEMBERSHIP_TYPES; i++)
249		if (!group->members[i])
250			leave_state |= (0x1 << i);
251
252	return leave_state & group->rec.join_state;
253}
254
255static int check_selector(ib_sa_comp_mask comp_mask,
256			  ib_sa_comp_mask selector_mask,
257			  ib_sa_comp_mask value_mask,
258			  u8 selector, u8 src_value, u8 dst_value)
259{
260	int err;
261
262	if (!(comp_mask & selector_mask) || !(comp_mask & value_mask))
263		return 0;
264
265	switch (selector) {
266	case IB_SA_GT:
267		err = (src_value <= dst_value);
268		break;
269	case IB_SA_LT:
270		err = (src_value >= dst_value);
271		break;
272	case IB_SA_EQ:
273		err = (src_value != dst_value);
274		break;
275	default:
276		err = 0;
277		break;
278	}
279
280	return err;
281}
282
283static int cmp_rec(struct ib_sa_mcmember_rec *src,
284		   struct ib_sa_mcmember_rec *dst, ib_sa_comp_mask comp_mask)
285{
286	/* MGID must already match */
287
288	if (comp_mask & IB_SA_MCMEMBER_REC_PORT_GID &&
289	    memcmp(&src->port_gid, &dst->port_gid, sizeof src->port_gid))
290		return -EINVAL;
291	if (comp_mask & IB_SA_MCMEMBER_REC_QKEY && src->qkey != dst->qkey)
292		return -EINVAL;
293	if (comp_mask & IB_SA_MCMEMBER_REC_MLID && src->mlid != dst->mlid)
294		return -EINVAL;
295	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_MTU_SELECTOR,
296			   IB_SA_MCMEMBER_REC_MTU, dst->mtu_selector,
297			   src->mtu, dst->mtu))
298		return -EINVAL;
299	if (comp_mask & IB_SA_MCMEMBER_REC_TRAFFIC_CLASS &&
300	    src->traffic_class != dst->traffic_class)
301		return -EINVAL;
302	if (comp_mask & IB_SA_MCMEMBER_REC_PKEY && src->pkey != dst->pkey)
303		return -EINVAL;
304	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_RATE_SELECTOR,
305			   IB_SA_MCMEMBER_REC_RATE, dst->rate_selector,
306			   src->rate, dst->rate))
307		return -EINVAL;
308	if (check_selector(comp_mask,
309			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME_SELECTOR,
310			   IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME,
311			   dst->packet_life_time_selector,
312			   src->packet_life_time, dst->packet_life_time))
313		return -EINVAL;
314	if (comp_mask & IB_SA_MCMEMBER_REC_SL && src->sl != dst->sl)
315		return -EINVAL;
316	if (comp_mask & IB_SA_MCMEMBER_REC_FLOW_LABEL &&
317	    src->flow_label != dst->flow_label)
318		return -EINVAL;
319	if (comp_mask & IB_SA_MCMEMBER_REC_HOP_LIMIT &&
320	    src->hop_limit != dst->hop_limit)
321		return -EINVAL;
322	if (comp_mask & IB_SA_MCMEMBER_REC_SCOPE && src->scope != dst->scope)
323		return -EINVAL;
324
325	/* join_state checked separately, proxy_join ignored */
326
327	return 0;
328}
329
330static int send_join(struct mcast_group *group, struct mcast_member *member)
331{
332	struct mcast_port *port = group->port;
333	int ret;
334
335	group->last_join = member;
336	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
337				       port->port_num, IB_MGMT_METHOD_SET,
338				       &member->multicast.rec,
339				       member->multicast.comp_mask,
340				       3000, GFP_KERNEL, join_handler, group,
341				       &group->query);
342	return (ret > 0) ? 0 : ret;
343}
344
345static int send_leave(struct mcast_group *group, u8 leave_state)
346{
347	struct mcast_port *port = group->port;
348	struct ib_sa_mcmember_rec rec;
349	int ret;
350
351	rec = group->rec;
352	rec.join_state = leave_state;
353	group->leave_state = leave_state;
354
355	ret = ib_sa_mcmember_rec_query(&sa_client, port->dev->device,
356				       port->port_num, IB_SA_METHOD_DELETE, &rec,
357				       IB_SA_MCMEMBER_REC_MGID     |
358				       IB_SA_MCMEMBER_REC_PORT_GID |
359				       IB_SA_MCMEMBER_REC_JOIN_STATE,
360				       3000, GFP_KERNEL, leave_handler,
361				       group, &group->query);
362	return (ret > 0) ? 0 : ret;
363}
364
365static void join_group(struct mcast_group *group, struct mcast_member *member,
366		       u8 join_state)
367{
368	member->state = MCAST_MEMBER;
369	adjust_membership(group, join_state, 1);
370	group->rec.join_state |= join_state;
371	member->multicast.rec = group->rec;
372	member->multicast.rec.join_state = join_state;
373	list_move(&member->list, &group->active_list);
374}
375
376static int fail_join(struct mcast_group *group, struct mcast_member *member,
377		     int status)
378{
379	spin_lock_irq(&group->lock);
380	list_del_init(&member->list);
381	spin_unlock_irq(&group->lock);
382	return member->multicast.callback(status, &member->multicast);
383}
384
385static void process_group_error(struct mcast_group *group)
386{
387	struct mcast_member *member;
388	int ret = 0;
389	u16 pkey_index;
390
391	if (group->state == MCAST_PKEY_EVENT)
392		ret = ib_find_pkey(group->port->dev->device,
393				   group->port->port_num,
394				   be16_to_cpu(group->rec.pkey), &pkey_index);
395
396	spin_lock_irq(&group->lock);
397	if (group->state == MCAST_PKEY_EVENT && !ret &&
398	    group->pkey_index == pkey_index)
399		goto out;
400
401	while (!list_empty(&group->active_list)) {
402		member = list_entry(group->active_list.next,
403				    struct mcast_member, list);
404		refcount_inc(&member->refcount);
405		list_del_init(&member->list);
406		adjust_membership(group, member->multicast.rec.join_state, -1);
407		member->state = MCAST_ERROR;
408		spin_unlock_irq(&group->lock);
409
410		ret = member->multicast.callback(-ENETRESET,
411						 &member->multicast);
412		deref_member(member);
413		if (ret)
414			ib_sa_free_multicast(&member->multicast);
415		spin_lock_irq(&group->lock);
416	}
417
418	group->rec.join_state = 0;
419out:
420	group->state = MCAST_BUSY;
421	spin_unlock_irq(&group->lock);
422}
423
424static void mcast_work_handler(struct work_struct *work)
425{
426	struct mcast_group *group;
427	struct mcast_member *member;
428	struct ib_sa_multicast *multicast;
429	int status, ret;
430	u8 join_state;
431
432	group = container_of(work, typeof(*group), work);
433retest:
434	spin_lock_irq(&group->lock);
435	while (!list_empty(&group->pending_list) ||
436	       (group->state != MCAST_BUSY)) {
437
438		if (group->state != MCAST_BUSY) {
439			spin_unlock_irq(&group->lock);
440			process_group_error(group);
441			goto retest;
442		}
443
444		member = list_entry(group->pending_list.next,
445				    struct mcast_member, list);
446		multicast = &member->multicast;
447		join_state = multicast->rec.join_state;
448		refcount_inc(&member->refcount);
449
450		if (join_state == (group->rec.join_state & join_state)) {
451			status = cmp_rec(&group->rec, &multicast->rec,
452					 multicast->comp_mask);
453			if (!status)
454				join_group(group, member, join_state);
455			else
456				list_del_init(&member->list);
457			spin_unlock_irq(&group->lock);
458			ret = multicast->callback(status, multicast);
459		} else {
460			spin_unlock_irq(&group->lock);
461			status = send_join(group, member);
462			if (!status) {
463				deref_member(member);
464				return;
465			}
466			ret = fail_join(group, member, status);
467		}
468
469		deref_member(member);
470		if (ret)
471			ib_sa_free_multicast(&member->multicast);
472		spin_lock_irq(&group->lock);
473	}
474
475	join_state = get_leave_state(group);
476	if (join_state) {
477		group->rec.join_state &= ~join_state;
478		spin_unlock_irq(&group->lock);
479		if (send_leave(group, join_state))
480			goto retest;
481	} else {
482		group->state = MCAST_IDLE;
483		spin_unlock_irq(&group->lock);
484		release_group(group);
485	}
486}
487
488/*
489 * Fail a join request if it is still active - at the head of the pending queue.
490 */
491static void process_join_error(struct mcast_group *group, int status)
492{
493	struct mcast_member *member;
494	int ret;
495
496	spin_lock_irq(&group->lock);
497	member = list_entry(group->pending_list.next,
498			    struct mcast_member, list);
499	if (group->last_join == member) {
500		refcount_inc(&member->refcount);
501		list_del_init(&member->list);
502		spin_unlock_irq(&group->lock);
503		ret = member->multicast.callback(status, &member->multicast);
504		deref_member(member);
505		if (ret)
506			ib_sa_free_multicast(&member->multicast);
507	} else
508		spin_unlock_irq(&group->lock);
509}
510
511static void join_handler(int status, struct ib_sa_mcmember_rec *rec,
512			 void *context)
513{
514	struct mcast_group *group = context;
515	u16 pkey_index = MCAST_INVALID_PKEY_INDEX;
516
517	if (status)
518		process_join_error(group, status);
519	else {
520		int mgids_changed, is_mgid0;
521
522		if (ib_find_pkey(group->port->dev->device,
523				 group->port->port_num, be16_to_cpu(rec->pkey),
524				 &pkey_index))
525			pkey_index = MCAST_INVALID_PKEY_INDEX;
526
527		spin_lock_irq(&group->port->lock);
528		if (group->state == MCAST_BUSY &&
529		    group->pkey_index == MCAST_INVALID_PKEY_INDEX)
530			group->pkey_index = pkey_index;
531		mgids_changed = memcmp(&rec->mgid, &group->rec.mgid,
532				       sizeof(group->rec.mgid));
533		group->rec = *rec;
534		if (mgids_changed) {
535			rb_erase(&group->node, &group->port->table);
536			is_mgid0 = !memcmp(&mgid0, &group->rec.mgid,
537					   sizeof(mgid0));
538			mcast_insert(group->port, group, is_mgid0);
539		}
540		spin_unlock_irq(&group->port->lock);
541	}
542	mcast_work_handler(&group->work);
543}
544
545static void leave_handler(int status, struct ib_sa_mcmember_rec *rec,
546			  void *context)
547{
548	struct mcast_group *group = context;
549
550	if (status && group->retries > 0 &&
551	    !send_leave(group, group->leave_state))
552		group->retries--;
553	else
554		mcast_work_handler(&group->work);
555}
556
557static struct mcast_group *acquire_group(struct mcast_port *port,
558					 union ib_gid *mgid, gfp_t gfp_mask)
559{
560	struct mcast_group *group, *cur_group;
561	unsigned long flags;
562	int is_mgid0;
563
564	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
565	if (!is_mgid0) {
566		spin_lock_irqsave(&port->lock, flags);
567		group = mcast_find(port, mgid);
568		if (group)
569			goto found;
570		spin_unlock_irqrestore(&port->lock, flags);
571	}
572
573	group = kzalloc(sizeof *group, gfp_mask);
574	if (!group)
575		return NULL;
576
577	group->retries = 3;
578	group->port = port;
579	group->rec.mgid = *mgid;
580	group->pkey_index = MCAST_INVALID_PKEY_INDEX;
581	INIT_LIST_HEAD(&group->pending_list);
582	INIT_LIST_HEAD(&group->active_list);
583	INIT_WORK(&group->work, mcast_work_handler);
584	spin_lock_init(&group->lock);
585
586	spin_lock_irqsave(&port->lock, flags);
587	cur_group = mcast_insert(port, group, is_mgid0);
588	if (cur_group) {
589		kfree(group);
590		group = cur_group;
591	} else
592		refcount_inc(&port->refcount);
593found:
594	atomic_inc(&group->refcount);
595	spin_unlock_irqrestore(&port->lock, flags);
596	return group;
597}
598
599/*
600 * We serialize all join requests to a single group to make our lives much
601 * easier.  Otherwise, two users could try to join the same group
602 * simultaneously, with different configurations, one could leave while the
603 * join is in progress, etc., which makes locking around error recovery
604 * difficult.
605 */
606struct ib_sa_multicast *
607ib_sa_join_multicast(struct ib_sa_client *client,
608		     struct ib_device *device, u32 port_num,
609		     struct ib_sa_mcmember_rec *rec,
610		     ib_sa_comp_mask comp_mask, gfp_t gfp_mask,
611		     int (*callback)(int status,
612				     struct ib_sa_multicast *multicast),
613		     void *context)
614{
615	struct mcast_device *dev;
616	struct mcast_member *member;
617	struct ib_sa_multicast *multicast;
618	int ret;
619
620	dev = ib_get_client_data(device, &mcast_client);
621	if (!dev)
622		return ERR_PTR(-ENODEV);
623
624	member = kmalloc(sizeof *member, gfp_mask);
625	if (!member)
626		return ERR_PTR(-ENOMEM);
627
628	ib_sa_client_get(client);
629	member->client = client;
630	member->multicast.rec = *rec;
631	member->multicast.comp_mask = comp_mask;
632	member->multicast.callback = callback;
633	member->multicast.context = context;
634	init_completion(&member->comp);
635	refcount_set(&member->refcount, 1);
636	member->state = MCAST_JOINING;
637
638	member->group = acquire_group(&dev->port[port_num - dev->start_port],
639				      &rec->mgid, gfp_mask);
640	if (!member->group) {
641		ret = -ENOMEM;
642		goto err;
643	}
644
645	/*
646	 * The user will get the multicast structure in their callback.  They
647	 * could then free the multicast structure before we can return from
648	 * this routine.  So we save the pointer to return before queuing
649	 * any callback.
650	 */
651	multicast = &member->multicast;
652	queue_join(member);
653	return multicast;
654
655err:
656	ib_sa_client_put(client);
657	kfree(member);
658	return ERR_PTR(ret);
659}
660EXPORT_SYMBOL(ib_sa_join_multicast);
661
662void ib_sa_free_multicast(struct ib_sa_multicast *multicast)
663{
664	struct mcast_member *member;
665	struct mcast_group *group;
666
667	member = container_of(multicast, struct mcast_member, multicast);
668	group = member->group;
669
670	spin_lock_irq(&group->lock);
671	if (member->state == MCAST_MEMBER)
672		adjust_membership(group, multicast->rec.join_state, -1);
673
674	list_del_init(&member->list);
675
676	if (group->state == MCAST_IDLE) {
677		group->state = MCAST_BUSY;
678		spin_unlock_irq(&group->lock);
679		/* Continue to hold reference on group until callback */
680		queue_work(mcast_wq, &group->work);
681	} else {
682		spin_unlock_irq(&group->lock);
683		release_group(group);
684	}
685
686	deref_member(member);
687	wait_for_completion(&member->comp);
688	ib_sa_client_put(member->client);
689	kfree(member);
690}
691EXPORT_SYMBOL(ib_sa_free_multicast);
692
693int ib_sa_get_mcmember_rec(struct ib_device *device, u32 port_num,
694			   union ib_gid *mgid, struct ib_sa_mcmember_rec *rec)
695{
696	struct mcast_device *dev;
697	struct mcast_port *port;
698	struct mcast_group *group;
699	unsigned long flags;
700	int ret = 0;
701
702	dev = ib_get_client_data(device, &mcast_client);
703	if (!dev)
704		return -ENODEV;
705
706	port = &dev->port[port_num - dev->start_port];
707	spin_lock_irqsave(&port->lock, flags);
708	group = mcast_find(port, mgid);
709	if (group)
710		*rec = group->rec;
711	else
712		ret = -EADDRNOTAVAIL;
713	spin_unlock_irqrestore(&port->lock, flags);
714
715	return ret;
716}
717EXPORT_SYMBOL(ib_sa_get_mcmember_rec);
718
719/**
720 * ib_init_ah_from_mcmember - Initialize AH attribute from multicast
721 * member record and gid of the device.
722 * @device:	RDMA device
723 * @port_num:	Port of the rdma device to consider
724 * @rec:	Multicast member record to use
725 * @ndev:	Optional netdevice, applicable only for RoCE
726 * @gid_type:	GID type to consider
727 * @ah_attr:	AH attribute to fillup on successful completion
728 *
729 * ib_init_ah_from_mcmember() initializes AH attribute based on multicast
730 * member record and other device properties. On success the caller is
731 * responsible to call rdma_destroy_ah_attr on the ah_attr. Returns 0 on
732 * success or appropriate error code.
733 *
734 */
735int ib_init_ah_from_mcmember(struct ib_device *device, u32 port_num,
736			     struct ib_sa_mcmember_rec *rec,
737			     struct net_device *ndev,
738			     enum ib_gid_type gid_type,
739			     struct rdma_ah_attr *ah_attr)
740{
741	const struct ib_gid_attr *sgid_attr;
742
743	/* GID table is not based on the netdevice for IB link layer,
744	 * so ignore ndev during search.
745	 */
746	if (rdma_protocol_ib(device, port_num))
747		ndev = NULL;
748	else if (!rdma_protocol_roce(device, port_num))
749		return -EINVAL;
750
751	sgid_attr = rdma_find_gid_by_port(device, &rec->port_gid,
752					  gid_type, port_num, ndev);
753	if (IS_ERR(sgid_attr))
754		return PTR_ERR(sgid_attr);
755
756	memset(ah_attr, 0, sizeof(*ah_attr));
757	ah_attr->type = rdma_ah_find_type(device, port_num);
758
759	rdma_ah_set_dlid(ah_attr, be16_to_cpu(rec->mlid));
760	rdma_ah_set_sl(ah_attr, rec->sl);
761	rdma_ah_set_port_num(ah_attr, port_num);
762	rdma_ah_set_static_rate(ah_attr, rec->rate);
763	rdma_move_grh_sgid_attr(ah_attr, &rec->mgid,
764				be32_to_cpu(rec->flow_label),
765				rec->hop_limit,	rec->traffic_class,
766				sgid_attr);
767	return 0;
768}
769EXPORT_SYMBOL(ib_init_ah_from_mcmember);
770
771static void mcast_groups_event(struct mcast_port *port,
772			       enum mcast_group_state state)
773{
774	struct mcast_group *group;
775	struct rb_node *node;
776	unsigned long flags;
777
778	spin_lock_irqsave(&port->lock, flags);
779	for (node = rb_first(&port->table); node; node = rb_next(node)) {
780		group = rb_entry(node, struct mcast_group, node);
781		spin_lock(&group->lock);
782		if (group->state == MCAST_IDLE) {
783			atomic_inc(&group->refcount);
784			queue_work(mcast_wq, &group->work);
785		}
786		if (group->state != MCAST_GROUP_ERROR)
787			group->state = state;
788		spin_unlock(&group->lock);
789	}
790	spin_unlock_irqrestore(&port->lock, flags);
791}
792
793static void mcast_event_handler(struct ib_event_handler *handler,
794				struct ib_event *event)
795{
796	struct mcast_device *dev;
797	int index;
798
799	dev = container_of(handler, struct mcast_device, event_handler);
800	if (!rdma_cap_ib_mcast(dev->device, event->element.port_num))
801		return;
802
803	index = event->element.port_num - dev->start_port;
804
805	switch (event->event) {
806	case IB_EVENT_PORT_ERR:
807	case IB_EVENT_LID_CHANGE:
808	case IB_EVENT_CLIENT_REREGISTER:
809		mcast_groups_event(&dev->port[index], MCAST_GROUP_ERROR);
810		break;
811	case IB_EVENT_PKEY_CHANGE:
812		mcast_groups_event(&dev->port[index], MCAST_PKEY_EVENT);
813		break;
814	default:
815		break;
816	}
817}
818
819static int mcast_add_one(struct ib_device *device)
820{
821	struct mcast_device *dev;
822	struct mcast_port *port;
823	int i;
824	int count = 0;
825
826	dev = kmalloc(struct_size(dev, port, device->phys_port_cnt),
827		      GFP_KERNEL);
828	if (!dev)
829		return -ENOMEM;
830
831	dev->start_port = rdma_start_port(device);
832	dev->end_port = rdma_end_port(device);
833
834	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
835		if (!rdma_cap_ib_mcast(device, dev->start_port + i))
836			continue;
837		port = &dev->port[i];
838		port->dev = dev;
839		port->port_num = dev->start_port + i;
840		spin_lock_init(&port->lock);
841		port->table = RB_ROOT;
842		init_completion(&port->comp);
843		refcount_set(&port->refcount, 1);
844		++count;
845	}
846
847	if (!count) {
848		kfree(dev);
849		return -EOPNOTSUPP;
850	}
851
852	dev->device = device;
853	ib_set_client_data(device, &mcast_client, dev);
854
855	INIT_IB_EVENT_HANDLER(&dev->event_handler, device, mcast_event_handler);
856	ib_register_event_handler(&dev->event_handler);
857	return 0;
858}
859
860static void mcast_remove_one(struct ib_device *device, void *client_data)
861{
862	struct mcast_device *dev = client_data;
863	struct mcast_port *port;
864	int i;
865
866	ib_unregister_event_handler(&dev->event_handler);
867	flush_workqueue(mcast_wq);
868
869	for (i = 0; i <= dev->end_port - dev->start_port; i++) {
870		if (rdma_cap_ib_mcast(device, dev->start_port + i)) {
871			port = &dev->port[i];
872			deref_port(port);
873			wait_for_completion(&port->comp);
874		}
875	}
876
877	kfree(dev);
878}
879
880int mcast_init(void)
881{
882	int ret;
883
884	mcast_wq = alloc_ordered_workqueue("ib_mcast", WQ_MEM_RECLAIM);
885	if (!mcast_wq)
886		return -ENOMEM;
887
888	ib_sa_register_client(&sa_client);
889
890	ret = ib_register_client(&mcast_client);
891	if (ret)
892		goto err;
893	return 0;
894
895err:
896	ib_sa_unregister_client(&sa_client);
897	destroy_workqueue(mcast_wq);
898	return ret;
899}
900
901void mcast_cleanup(void)
902{
903	ib_unregister_client(&mcast_client);
904	ib_sa_unregister_client(&sa_client);
905	destroy_workqueue(mcast_wq);
906}
907