xref: /linux/drivers/infiniband/ulp/ipoib/ipoib_multicast.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
4  * Copyright (c) 2004 Voltaire, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/skbuff.h>
36 #include <linux/rtnetlink.h>
37 #include <linux/moduleparam.h>
38 #include <linux/ip.h>
39 #include <linux/in.h>
40 #include <linux/igmp.h>
41 #include <linux/inetdevice.h>
42 #include <linux/delay.h>
43 #include <linux/completion.h>
44 #include <linux/slab.h>
45 
46 #include <net/dst.h>
47 
48 #include "ipoib.h"
49 
50 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
51 static int mcast_debug_level;
52 
53 module_param(mcast_debug_level, int, 0644);
54 MODULE_PARM_DESC(mcast_debug_level,
55 		 "Enable multicast debug tracing if > 0");
56 #endif
57 
58 static DEFINE_MUTEX(mcast_mutex);
59 
60 struct ipoib_mcast_iter {
61 	struct net_device *dev;
62 	union ib_gid       mgid;
63 	unsigned long      created;
64 	unsigned int       queuelen;
65 	unsigned int       complete;
66 	unsigned int       send_only;
67 };
68 
69 static void ipoib_mcast_free(struct ipoib_mcast *mcast)
70 {
71 	struct net_device *dev = mcast->dev;
72 	struct ipoib_dev_priv *priv = netdev_priv(dev);
73 	struct ipoib_neigh *neigh, *tmp;
74 	int tx_dropped = 0;
75 
76 	ipoib_dbg_mcast(netdev_priv(dev), "deleting multicast group %pI6\n",
77 			mcast->mcmember.mgid.raw);
78 
79 	spin_lock_irq(&priv->lock);
80 
81 	list_for_each_entry_safe(neigh, tmp, &mcast->neigh_list, list) {
82 		/*
83 		 * It's safe to call ipoib_put_ah() inside priv->lock
84 		 * here, because we know that mcast->ah will always
85 		 * hold one more reference, so ipoib_put_ah() will
86 		 * never do more than decrement the ref count.
87 		 */
88 		if (neigh->ah)
89 			ipoib_put_ah(neigh->ah);
90 		ipoib_neigh_free(dev, neigh);
91 	}
92 
93 	spin_unlock_irq(&priv->lock);
94 
95 	if (mcast->ah)
96 		ipoib_put_ah(mcast->ah);
97 
98 	while (!skb_queue_empty(&mcast->pkt_queue)) {
99 		++tx_dropped;
100 		dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
101 	}
102 
103 	netif_tx_lock_bh(dev);
104 	dev->stats.tx_dropped += tx_dropped;
105 	netif_tx_unlock_bh(dev);
106 
107 	kfree(mcast);
108 }
109 
110 static struct ipoib_mcast *ipoib_mcast_alloc(struct net_device *dev,
111 					     int can_sleep)
112 {
113 	struct ipoib_mcast *mcast;
114 
115 	mcast = kzalloc(sizeof *mcast, can_sleep ? GFP_KERNEL : GFP_ATOMIC);
116 	if (!mcast)
117 		return NULL;
118 
119 	mcast->dev = dev;
120 	mcast->created = jiffies;
121 	mcast->backoff = 1;
122 
123 	INIT_LIST_HEAD(&mcast->list);
124 	INIT_LIST_HEAD(&mcast->neigh_list);
125 	skb_queue_head_init(&mcast->pkt_queue);
126 
127 	return mcast;
128 }
129 
130 static struct ipoib_mcast *__ipoib_mcast_find(struct net_device *dev, void *mgid)
131 {
132 	struct ipoib_dev_priv *priv = netdev_priv(dev);
133 	struct rb_node *n = priv->multicast_tree.rb_node;
134 
135 	while (n) {
136 		struct ipoib_mcast *mcast;
137 		int ret;
138 
139 		mcast = rb_entry(n, struct ipoib_mcast, rb_node);
140 
141 		ret = memcmp(mgid, mcast->mcmember.mgid.raw,
142 			     sizeof (union ib_gid));
143 		if (ret < 0)
144 			n = n->rb_left;
145 		else if (ret > 0)
146 			n = n->rb_right;
147 		else
148 			return mcast;
149 	}
150 
151 	return NULL;
152 }
153 
154 static int __ipoib_mcast_add(struct net_device *dev, struct ipoib_mcast *mcast)
155 {
156 	struct ipoib_dev_priv *priv = netdev_priv(dev);
157 	struct rb_node **n = &priv->multicast_tree.rb_node, *pn = NULL;
158 
159 	while (*n) {
160 		struct ipoib_mcast *tmcast;
161 		int ret;
162 
163 		pn = *n;
164 		tmcast = rb_entry(pn, struct ipoib_mcast, rb_node);
165 
166 		ret = memcmp(mcast->mcmember.mgid.raw, tmcast->mcmember.mgid.raw,
167 			     sizeof (union ib_gid));
168 		if (ret < 0)
169 			n = &pn->rb_left;
170 		else if (ret > 0)
171 			n = &pn->rb_right;
172 		else
173 			return -EEXIST;
174 	}
175 
176 	rb_link_node(&mcast->rb_node, pn, n);
177 	rb_insert_color(&mcast->rb_node, &priv->multicast_tree);
178 
179 	return 0;
180 }
181 
182 static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
183 				   struct ib_sa_mcmember_rec *mcmember)
184 {
185 	struct net_device *dev = mcast->dev;
186 	struct ipoib_dev_priv *priv = netdev_priv(dev);
187 	struct ipoib_ah *ah;
188 	int ret;
189 	int set_qkey = 0;
190 
191 	mcast->mcmember = *mcmember;
192 
193 	/* Set the cached Q_Key before we attach if it's the broadcast group */
194 	if (!memcmp(mcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
195 		    sizeof (union ib_gid))) {
196 		spin_lock_irq(&priv->lock);
197 		if (!priv->broadcast) {
198 			spin_unlock_irq(&priv->lock);
199 			return -EAGAIN;
200 		}
201 		priv->qkey = be32_to_cpu(priv->broadcast->mcmember.qkey);
202 		spin_unlock_irq(&priv->lock);
203 		priv->tx_wr.wr.ud.remote_qkey = priv->qkey;
204 		set_qkey = 1;
205 	}
206 
207 	if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
208 		if (test_and_set_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags)) {
209 			ipoib_warn(priv, "multicast group %pI6 already attached\n",
210 				   mcast->mcmember.mgid.raw);
211 
212 			return 0;
213 		}
214 
215 		ret = ipoib_mcast_attach(dev, be16_to_cpu(mcast->mcmember.mlid),
216 					 &mcast->mcmember.mgid, set_qkey);
217 		if (ret < 0) {
218 			ipoib_warn(priv, "couldn't attach QP to multicast group %pI6\n",
219 				   mcast->mcmember.mgid.raw);
220 
221 			clear_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags);
222 			return ret;
223 		}
224 	}
225 
226 	{
227 		struct ib_ah_attr av = {
228 			.dlid	       = be16_to_cpu(mcast->mcmember.mlid),
229 			.port_num      = priv->port,
230 			.sl	       = mcast->mcmember.sl,
231 			.ah_flags      = IB_AH_GRH,
232 			.static_rate   = mcast->mcmember.rate,
233 			.grh	       = {
234 				.flow_label    = be32_to_cpu(mcast->mcmember.flow_label),
235 				.hop_limit     = mcast->mcmember.hop_limit,
236 				.sgid_index    = 0,
237 				.traffic_class = mcast->mcmember.traffic_class
238 			}
239 		};
240 		av.grh.dgid = mcast->mcmember.mgid;
241 
242 		ah = ipoib_create_ah(dev, priv->pd, &av);
243 		if (!ah) {
244 			ipoib_warn(priv, "ib_address_create failed\n");
245 		} else {
246 			spin_lock_irq(&priv->lock);
247 			mcast->ah = ah;
248 			spin_unlock_irq(&priv->lock);
249 
250 			ipoib_dbg_mcast(priv, "MGID %pI6 AV %p, LID 0x%04x, SL %d\n",
251 					mcast->mcmember.mgid.raw,
252 					mcast->ah->ah,
253 					be16_to_cpu(mcast->mcmember.mlid),
254 					mcast->mcmember.sl);
255 		}
256 	}
257 
258 	/* actually send any queued packets */
259 	netif_tx_lock_bh(dev);
260 	while (!skb_queue_empty(&mcast->pkt_queue)) {
261 		struct sk_buff *skb = skb_dequeue(&mcast->pkt_queue);
262 		struct dst_entry *dst = skb_dst(skb);
263 		struct neighbour *n = NULL;
264 
265 		netif_tx_unlock_bh(dev);
266 
267 		skb->dev = dev;
268 		if (dst)
269 			n = dst_get_neighbour(dst);
270 		if (!dst || !n) {
271 			/* put pseudoheader back on for next time */
272 			skb_push(skb, sizeof (struct ipoib_pseudoheader));
273 		}
274 
275 		if (dev_queue_xmit(skb))
276 			ipoib_warn(priv, "dev_queue_xmit failed to requeue packet\n");
277 		netif_tx_lock_bh(dev);
278 	}
279 	netif_tx_unlock_bh(dev);
280 
281 	return 0;
282 }
283 
284 static int
285 ipoib_mcast_sendonly_join_complete(int status,
286 				   struct ib_sa_multicast *multicast)
287 {
288 	struct ipoib_mcast *mcast = multicast->context;
289 	struct net_device *dev = mcast->dev;
290 
291 	/* We trap for port events ourselves. */
292 	if (status == -ENETRESET)
293 		return 0;
294 
295 	if (!status)
296 		status = ipoib_mcast_join_finish(mcast, &multicast->rec);
297 
298 	if (status) {
299 		if (mcast->logcount++ < 20)
300 			ipoib_dbg_mcast(netdev_priv(dev), "multicast join failed for %pI6, status %d\n",
301 					mcast->mcmember.mgid.raw, status);
302 
303 		/* Flush out any queued packets */
304 		netif_tx_lock_bh(dev);
305 		while (!skb_queue_empty(&mcast->pkt_queue)) {
306 			++dev->stats.tx_dropped;
307 			dev_kfree_skb_any(skb_dequeue(&mcast->pkt_queue));
308 		}
309 		netif_tx_unlock_bh(dev);
310 
311 		/* Clear the busy flag so we try again */
312 		status = test_and_clear_bit(IPOIB_MCAST_FLAG_BUSY,
313 					    &mcast->flags);
314 	}
315 	return status;
316 }
317 
318 static int ipoib_mcast_sendonly_join(struct ipoib_mcast *mcast)
319 {
320 	struct net_device *dev = mcast->dev;
321 	struct ipoib_dev_priv *priv = netdev_priv(dev);
322 	struct ib_sa_mcmember_rec rec = {
323 #if 0				/* Some SMs don't support send-only yet */
324 		.join_state = 4
325 #else
326 		.join_state = 1
327 #endif
328 	};
329 	int ret = 0;
330 
331 	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) {
332 		ipoib_dbg_mcast(priv, "device shutting down, no multicast joins\n");
333 		return -ENODEV;
334 	}
335 
336 	if (test_and_set_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags)) {
337 		ipoib_dbg_mcast(priv, "multicast entry busy, skipping\n");
338 		return -EBUSY;
339 	}
340 
341 	rec.mgid     = mcast->mcmember.mgid;
342 	rec.port_gid = priv->local_gid;
343 	rec.pkey     = cpu_to_be16(priv->pkey);
344 
345 	mcast->mc = ib_sa_join_multicast(&ipoib_sa_client, priv->ca,
346 					 priv->port, &rec,
347 					 IB_SA_MCMEMBER_REC_MGID	|
348 					 IB_SA_MCMEMBER_REC_PORT_GID	|
349 					 IB_SA_MCMEMBER_REC_PKEY	|
350 					 IB_SA_MCMEMBER_REC_JOIN_STATE,
351 					 GFP_ATOMIC,
352 					 ipoib_mcast_sendonly_join_complete,
353 					 mcast);
354 	if (IS_ERR(mcast->mc)) {
355 		ret = PTR_ERR(mcast->mc);
356 		clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
357 		ipoib_warn(priv, "ib_sa_join_multicast failed (ret = %d)\n",
358 			   ret);
359 	} else {
360 		ipoib_dbg_mcast(priv, "no multicast record for %pI6, starting join\n",
361 				mcast->mcmember.mgid.raw);
362 	}
363 
364 	return ret;
365 }
366 
367 void ipoib_mcast_carrier_on_task(struct work_struct *work)
368 {
369 	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
370 						   carrier_on_task);
371 	struct ib_port_attr attr;
372 
373 	/*
374 	 * Take rtnl_lock to avoid racing with ipoib_stop() and
375 	 * turning the carrier back on while a device is being
376 	 * removed.
377 	 */
378 	if (ib_query_port(priv->ca, priv->port, &attr) ||
379 	    attr.state != IB_PORT_ACTIVE) {
380 		ipoib_dbg(priv, "Keeping carrier off until IB port is active\n");
381 		return;
382 	}
383 
384 	rtnl_lock();
385 	netif_carrier_on(priv->dev);
386 	rtnl_unlock();
387 }
388 
389 static int ipoib_mcast_join_complete(int status,
390 				     struct ib_sa_multicast *multicast)
391 {
392 	struct ipoib_mcast *mcast = multicast->context;
393 	struct net_device *dev = mcast->dev;
394 	struct ipoib_dev_priv *priv = netdev_priv(dev);
395 
396 	ipoib_dbg_mcast(priv, "join completion for %pI6 (status %d)\n",
397 			mcast->mcmember.mgid.raw, status);
398 
399 	/* We trap for port events ourselves. */
400 	if (status == -ENETRESET)
401 		return 0;
402 
403 	if (!status)
404 		status = ipoib_mcast_join_finish(mcast, &multicast->rec);
405 
406 	if (!status) {
407 		mcast->backoff = 1;
408 		mutex_lock(&mcast_mutex);
409 		if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
410 			queue_delayed_work(ipoib_workqueue,
411 					   &priv->mcast_task, 0);
412 		mutex_unlock(&mcast_mutex);
413 
414 		/*
415 		 * Defer carrier on work to ipoib_workqueue to avoid a
416 		 * deadlock on rtnl_lock here.
417 		 */
418 		if (mcast == priv->broadcast)
419 			queue_work(ipoib_workqueue, &priv->carrier_on_task);
420 
421 		return 0;
422 	}
423 
424 	if (mcast->logcount++ < 20) {
425 		if (status == -ETIMEDOUT || status == -EAGAIN) {
426 			ipoib_dbg_mcast(priv, "multicast join failed for %pI6, status %d\n",
427 					mcast->mcmember.mgid.raw, status);
428 		} else {
429 			ipoib_warn(priv, "multicast join failed for %pI6, status %d\n",
430 				   mcast->mcmember.mgid.raw, status);
431 		}
432 	}
433 
434 	mcast->backoff *= 2;
435 	if (mcast->backoff > IPOIB_MAX_BACKOFF_SECONDS)
436 		mcast->backoff = IPOIB_MAX_BACKOFF_SECONDS;
437 
438 	/* Clear the busy flag so we try again */
439 	status = test_and_clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
440 
441 	mutex_lock(&mcast_mutex);
442 	spin_lock_irq(&priv->lock);
443 	if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
444 		queue_delayed_work(ipoib_workqueue, &priv->mcast_task,
445 				   mcast->backoff * HZ);
446 	spin_unlock_irq(&priv->lock);
447 	mutex_unlock(&mcast_mutex);
448 
449 	return status;
450 }
451 
452 static void ipoib_mcast_join(struct net_device *dev, struct ipoib_mcast *mcast,
453 			     int create)
454 {
455 	struct ipoib_dev_priv *priv = netdev_priv(dev);
456 	struct ib_sa_mcmember_rec rec = {
457 		.join_state = 1
458 	};
459 	ib_sa_comp_mask comp_mask;
460 	int ret = 0;
461 
462 	ipoib_dbg_mcast(priv, "joining MGID %pI6\n", mcast->mcmember.mgid.raw);
463 
464 	rec.mgid     = mcast->mcmember.mgid;
465 	rec.port_gid = priv->local_gid;
466 	rec.pkey     = cpu_to_be16(priv->pkey);
467 
468 	comp_mask =
469 		IB_SA_MCMEMBER_REC_MGID		|
470 		IB_SA_MCMEMBER_REC_PORT_GID	|
471 		IB_SA_MCMEMBER_REC_PKEY		|
472 		IB_SA_MCMEMBER_REC_JOIN_STATE;
473 
474 	if (create) {
475 		comp_mask |=
476 			IB_SA_MCMEMBER_REC_QKEY			|
477 			IB_SA_MCMEMBER_REC_MTU_SELECTOR		|
478 			IB_SA_MCMEMBER_REC_MTU			|
479 			IB_SA_MCMEMBER_REC_TRAFFIC_CLASS	|
480 			IB_SA_MCMEMBER_REC_RATE_SELECTOR	|
481 			IB_SA_MCMEMBER_REC_RATE			|
482 			IB_SA_MCMEMBER_REC_SL			|
483 			IB_SA_MCMEMBER_REC_FLOW_LABEL		|
484 			IB_SA_MCMEMBER_REC_HOP_LIMIT;
485 
486 		rec.qkey	  = priv->broadcast->mcmember.qkey;
487 		rec.mtu_selector  = IB_SA_EQ;
488 		rec.mtu		  = priv->broadcast->mcmember.mtu;
489 		rec.traffic_class = priv->broadcast->mcmember.traffic_class;
490 		rec.rate_selector = IB_SA_EQ;
491 		rec.rate	  = priv->broadcast->mcmember.rate;
492 		rec.sl		  = priv->broadcast->mcmember.sl;
493 		rec.flow_label	  = priv->broadcast->mcmember.flow_label;
494 		rec.hop_limit	  = priv->broadcast->mcmember.hop_limit;
495 	}
496 
497 	set_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
498 	mcast->mc = ib_sa_join_multicast(&ipoib_sa_client, priv->ca, priv->port,
499 					 &rec, comp_mask, GFP_KERNEL,
500 					 ipoib_mcast_join_complete, mcast);
501 	if (IS_ERR(mcast->mc)) {
502 		clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags);
503 		ret = PTR_ERR(mcast->mc);
504 		ipoib_warn(priv, "ib_sa_join_multicast failed, status %d\n", ret);
505 
506 		mcast->backoff *= 2;
507 		if (mcast->backoff > IPOIB_MAX_BACKOFF_SECONDS)
508 			mcast->backoff = IPOIB_MAX_BACKOFF_SECONDS;
509 
510 		mutex_lock(&mcast_mutex);
511 		if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
512 			queue_delayed_work(ipoib_workqueue,
513 					   &priv->mcast_task,
514 					   mcast->backoff * HZ);
515 		mutex_unlock(&mcast_mutex);
516 	}
517 }
518 
519 void ipoib_mcast_join_task(struct work_struct *work)
520 {
521 	struct ipoib_dev_priv *priv =
522 		container_of(work, struct ipoib_dev_priv, mcast_task.work);
523 	struct net_device *dev = priv->dev;
524 
525 	if (!test_bit(IPOIB_MCAST_RUN, &priv->flags))
526 		return;
527 
528 	if (ib_query_gid(priv->ca, priv->port, 0, &priv->local_gid))
529 		ipoib_warn(priv, "ib_query_gid() failed\n");
530 	else
531 		memcpy(priv->dev->dev_addr + 4, priv->local_gid.raw, sizeof (union ib_gid));
532 
533 	{
534 		struct ib_port_attr attr;
535 
536 		if (!ib_query_port(priv->ca, priv->port, &attr))
537 			priv->local_lid = attr.lid;
538 		else
539 			ipoib_warn(priv, "ib_query_port failed\n");
540 	}
541 
542 	if (!priv->broadcast) {
543 		struct ipoib_mcast *broadcast;
544 
545 		if (!test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
546 			return;
547 
548 		broadcast = ipoib_mcast_alloc(dev, 1);
549 		if (!broadcast) {
550 			ipoib_warn(priv, "failed to allocate broadcast group\n");
551 			mutex_lock(&mcast_mutex);
552 			if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
553 				queue_delayed_work(ipoib_workqueue,
554 						   &priv->mcast_task, HZ);
555 			mutex_unlock(&mcast_mutex);
556 			return;
557 		}
558 
559 		spin_lock_irq(&priv->lock);
560 		memcpy(broadcast->mcmember.mgid.raw, priv->dev->broadcast + 4,
561 		       sizeof (union ib_gid));
562 		priv->broadcast = broadcast;
563 
564 		__ipoib_mcast_add(dev, priv->broadcast);
565 		spin_unlock_irq(&priv->lock);
566 	}
567 
568 	if (!test_bit(IPOIB_MCAST_FLAG_ATTACHED, &priv->broadcast->flags)) {
569 		if (!test_bit(IPOIB_MCAST_FLAG_BUSY, &priv->broadcast->flags))
570 			ipoib_mcast_join(dev, priv->broadcast, 0);
571 		return;
572 	}
573 
574 	while (1) {
575 		struct ipoib_mcast *mcast = NULL;
576 
577 		spin_lock_irq(&priv->lock);
578 		list_for_each_entry(mcast, &priv->multicast_list, list) {
579 			if (!test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)
580 			    && !test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags)
581 			    && !test_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags)) {
582 				/* Found the next unjoined group */
583 				break;
584 			}
585 		}
586 		spin_unlock_irq(&priv->lock);
587 
588 		if (&mcast->list == &priv->multicast_list) {
589 			/* All done */
590 			break;
591 		}
592 
593 		ipoib_mcast_join(dev, mcast, 1);
594 		return;
595 	}
596 
597 	priv->mcast_mtu = IPOIB_UD_MTU(ib_mtu_enum_to_int(priv->broadcast->mcmember.mtu));
598 
599 	if (!ipoib_cm_admin_enabled(dev)) {
600 		rtnl_lock();
601 		dev_set_mtu(dev, min(priv->mcast_mtu, priv->admin_mtu));
602 		rtnl_unlock();
603 	}
604 
605 	ipoib_dbg_mcast(priv, "successfully joined all multicast groups\n");
606 
607 	clear_bit(IPOIB_MCAST_RUN, &priv->flags);
608 }
609 
610 int ipoib_mcast_start_thread(struct net_device *dev)
611 {
612 	struct ipoib_dev_priv *priv = netdev_priv(dev);
613 
614 	ipoib_dbg_mcast(priv, "starting multicast thread\n");
615 
616 	mutex_lock(&mcast_mutex);
617 	if (!test_and_set_bit(IPOIB_MCAST_RUN, &priv->flags))
618 		queue_delayed_work(ipoib_workqueue, &priv->mcast_task, 0);
619 	mutex_unlock(&mcast_mutex);
620 
621 	return 0;
622 }
623 
624 int ipoib_mcast_stop_thread(struct net_device *dev, int flush)
625 {
626 	struct ipoib_dev_priv *priv = netdev_priv(dev);
627 
628 	ipoib_dbg_mcast(priv, "stopping multicast thread\n");
629 
630 	mutex_lock(&mcast_mutex);
631 	clear_bit(IPOIB_MCAST_RUN, &priv->flags);
632 	cancel_delayed_work(&priv->mcast_task);
633 	mutex_unlock(&mcast_mutex);
634 
635 	if (flush)
636 		flush_workqueue(ipoib_workqueue);
637 
638 	return 0;
639 }
640 
641 static int ipoib_mcast_leave(struct net_device *dev, struct ipoib_mcast *mcast)
642 {
643 	struct ipoib_dev_priv *priv = netdev_priv(dev);
644 	int ret = 0;
645 
646 	if (test_and_clear_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
647 		ib_sa_free_multicast(mcast->mc);
648 
649 	if (test_and_clear_bit(IPOIB_MCAST_FLAG_ATTACHED, &mcast->flags)) {
650 		ipoib_dbg_mcast(priv, "leaving MGID %pI6\n",
651 				mcast->mcmember.mgid.raw);
652 
653 		/* Remove ourselves from the multicast group */
654 		ret = ib_detach_mcast(priv->qp, &mcast->mcmember.mgid,
655 				      be16_to_cpu(mcast->mcmember.mlid));
656 		if (ret)
657 			ipoib_warn(priv, "ib_detach_mcast failed (result = %d)\n", ret);
658 	}
659 
660 	return 0;
661 }
662 
663 void ipoib_mcast_send(struct net_device *dev, void *mgid, struct sk_buff *skb)
664 {
665 	struct ipoib_dev_priv *priv = netdev_priv(dev);
666 	struct ipoib_mcast *mcast;
667 	unsigned long flags;
668 
669 	spin_lock_irqsave(&priv->lock, flags);
670 
671 	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)		||
672 	    !priv->broadcast					||
673 	    !test_bit(IPOIB_MCAST_FLAG_ATTACHED, &priv->broadcast->flags)) {
674 		++dev->stats.tx_dropped;
675 		dev_kfree_skb_any(skb);
676 		goto unlock;
677 	}
678 
679 	mcast = __ipoib_mcast_find(dev, mgid);
680 	if (!mcast) {
681 		/* Let's create a new send only group now */
682 		ipoib_dbg_mcast(priv, "setting up send only multicast group for %pI6\n",
683 				mgid);
684 
685 		mcast = ipoib_mcast_alloc(dev, 0);
686 		if (!mcast) {
687 			ipoib_warn(priv, "unable to allocate memory for "
688 				   "multicast structure\n");
689 			++dev->stats.tx_dropped;
690 			dev_kfree_skb_any(skb);
691 			goto out;
692 		}
693 
694 		set_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags);
695 		memcpy(mcast->mcmember.mgid.raw, mgid, sizeof (union ib_gid));
696 		__ipoib_mcast_add(dev, mcast);
697 		list_add_tail(&mcast->list, &priv->multicast_list);
698 	}
699 
700 	if (!mcast->ah) {
701 		if (skb_queue_len(&mcast->pkt_queue) < IPOIB_MAX_MCAST_QUEUE)
702 			skb_queue_tail(&mcast->pkt_queue, skb);
703 		else {
704 			++dev->stats.tx_dropped;
705 			dev_kfree_skb_any(skb);
706 		}
707 
708 		if (test_bit(IPOIB_MCAST_FLAG_BUSY, &mcast->flags))
709 			ipoib_dbg_mcast(priv, "no address vector, "
710 					"but multicast join already started\n");
711 		else if (test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags))
712 			ipoib_mcast_sendonly_join(mcast);
713 
714 		/*
715 		 * If lookup completes between here and out:, don't
716 		 * want to send packet twice.
717 		 */
718 		mcast = NULL;
719 	}
720 
721 out:
722 	if (mcast && mcast->ah) {
723 		struct dst_entry *dst = skb_dst(skb);
724 		struct neighbour *n = NULL;
725 		if (dst)
726 			n = dst_get_neighbour(dst);
727 		if (n && !*to_ipoib_neigh(n)) {
728 			struct ipoib_neigh *neigh = ipoib_neigh_alloc(n,
729 								      skb->dev);
730 
731 			if (neigh) {
732 				kref_get(&mcast->ah->ref);
733 				neigh->ah	= mcast->ah;
734 				list_add_tail(&neigh->list, &mcast->neigh_list);
735 			}
736 		}
737 
738 		spin_unlock_irqrestore(&priv->lock, flags);
739 		ipoib_send(dev, skb, mcast->ah, IB_MULTICAST_QPN);
740 		return;
741 	}
742 
743 unlock:
744 	spin_unlock_irqrestore(&priv->lock, flags);
745 }
746 
747 void ipoib_mcast_dev_flush(struct net_device *dev)
748 {
749 	struct ipoib_dev_priv *priv = netdev_priv(dev);
750 	LIST_HEAD(remove_list);
751 	struct ipoib_mcast *mcast, *tmcast;
752 	unsigned long flags;
753 
754 	ipoib_dbg_mcast(priv, "flushing multicast list\n");
755 
756 	spin_lock_irqsave(&priv->lock, flags);
757 
758 	list_for_each_entry_safe(mcast, tmcast, &priv->multicast_list, list) {
759 		list_del(&mcast->list);
760 		rb_erase(&mcast->rb_node, &priv->multicast_tree);
761 		list_add_tail(&mcast->list, &remove_list);
762 	}
763 
764 	if (priv->broadcast) {
765 		rb_erase(&priv->broadcast->rb_node, &priv->multicast_tree);
766 		list_add_tail(&priv->broadcast->list, &remove_list);
767 		priv->broadcast = NULL;
768 	}
769 
770 	spin_unlock_irqrestore(&priv->lock, flags);
771 
772 	list_for_each_entry_safe(mcast, tmcast, &remove_list, list) {
773 		ipoib_mcast_leave(dev, mcast);
774 		ipoib_mcast_free(mcast);
775 	}
776 }
777 
778 static int ipoib_mcast_addr_is_valid(const u8 *addr, const u8 *broadcast)
779 {
780 	/* reserved QPN, prefix, scope */
781 	if (memcmp(addr, broadcast, 6))
782 		return 0;
783 	/* signature lower, pkey */
784 	if (memcmp(addr + 7, broadcast + 7, 3))
785 		return 0;
786 	return 1;
787 }
788 
789 void ipoib_mcast_restart_task(struct work_struct *work)
790 {
791 	struct ipoib_dev_priv *priv =
792 		container_of(work, struct ipoib_dev_priv, restart_task);
793 	struct net_device *dev = priv->dev;
794 	struct netdev_hw_addr *ha;
795 	struct ipoib_mcast *mcast, *tmcast;
796 	LIST_HEAD(remove_list);
797 	unsigned long flags;
798 	struct ib_sa_mcmember_rec rec;
799 
800 	ipoib_dbg_mcast(priv, "restarting multicast task\n");
801 
802 	ipoib_mcast_stop_thread(dev, 0);
803 
804 	local_irq_save(flags);
805 	netif_addr_lock(dev);
806 	spin_lock(&priv->lock);
807 
808 	/*
809 	 * Unfortunately, the networking core only gives us a list of all of
810 	 * the multicast hardware addresses. We need to figure out which ones
811 	 * are new and which ones have been removed
812 	 */
813 
814 	/* Clear out the found flag */
815 	list_for_each_entry(mcast, &priv->multicast_list, list)
816 		clear_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags);
817 
818 	/* Mark all of the entries that are found or don't exist */
819 	netdev_for_each_mc_addr(ha, dev) {
820 		union ib_gid mgid;
821 
822 		if (!ipoib_mcast_addr_is_valid(ha->addr, dev->broadcast))
823 			continue;
824 
825 		memcpy(mgid.raw, ha->addr + 4, sizeof mgid);
826 
827 		mcast = __ipoib_mcast_find(dev, &mgid);
828 		if (!mcast || test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
829 			struct ipoib_mcast *nmcast;
830 
831 			/* ignore group which is directly joined by userspace */
832 			if (test_bit(IPOIB_FLAG_UMCAST, &priv->flags) &&
833 			    !ib_sa_get_mcmember_rec(priv->ca, priv->port, &mgid, &rec)) {
834 				ipoib_dbg_mcast(priv, "ignoring multicast entry for mgid %pI6\n",
835 						mgid.raw);
836 				continue;
837 			}
838 
839 			/* Not found or send-only group, let's add a new entry */
840 			ipoib_dbg_mcast(priv, "adding multicast entry for mgid %pI6\n",
841 					mgid.raw);
842 
843 			nmcast = ipoib_mcast_alloc(dev, 0);
844 			if (!nmcast) {
845 				ipoib_warn(priv, "unable to allocate memory for multicast structure\n");
846 				continue;
847 			}
848 
849 			set_bit(IPOIB_MCAST_FLAG_FOUND, &nmcast->flags);
850 
851 			nmcast->mcmember.mgid = mgid;
852 
853 			if (mcast) {
854 				/* Destroy the send only entry */
855 				list_move_tail(&mcast->list, &remove_list);
856 
857 				rb_replace_node(&mcast->rb_node,
858 						&nmcast->rb_node,
859 						&priv->multicast_tree);
860 			} else
861 				__ipoib_mcast_add(dev, nmcast);
862 
863 			list_add_tail(&nmcast->list, &priv->multicast_list);
864 		}
865 
866 		if (mcast)
867 			set_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags);
868 	}
869 
870 	/* Remove all of the entries don't exist anymore */
871 	list_for_each_entry_safe(mcast, tmcast, &priv->multicast_list, list) {
872 		if (!test_bit(IPOIB_MCAST_FLAG_FOUND, &mcast->flags) &&
873 		    !test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags)) {
874 			ipoib_dbg_mcast(priv, "deleting multicast group %pI6\n",
875 					mcast->mcmember.mgid.raw);
876 
877 			rb_erase(&mcast->rb_node, &priv->multicast_tree);
878 
879 			/* Move to the remove list */
880 			list_move_tail(&mcast->list, &remove_list);
881 		}
882 	}
883 
884 	spin_unlock(&priv->lock);
885 	netif_addr_unlock(dev);
886 	local_irq_restore(flags);
887 
888 	/* We have to cancel outside of the spinlock */
889 	list_for_each_entry_safe(mcast, tmcast, &remove_list, list) {
890 		ipoib_mcast_leave(mcast->dev, mcast);
891 		ipoib_mcast_free(mcast);
892 	}
893 
894 	if (test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
895 		ipoib_mcast_start_thread(dev);
896 }
897 
898 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
899 
900 struct ipoib_mcast_iter *ipoib_mcast_iter_init(struct net_device *dev)
901 {
902 	struct ipoib_mcast_iter *iter;
903 
904 	iter = kmalloc(sizeof *iter, GFP_KERNEL);
905 	if (!iter)
906 		return NULL;
907 
908 	iter->dev = dev;
909 	memset(iter->mgid.raw, 0, 16);
910 
911 	if (ipoib_mcast_iter_next(iter)) {
912 		kfree(iter);
913 		return NULL;
914 	}
915 
916 	return iter;
917 }
918 
919 int ipoib_mcast_iter_next(struct ipoib_mcast_iter *iter)
920 {
921 	struct ipoib_dev_priv *priv = netdev_priv(iter->dev);
922 	struct rb_node *n;
923 	struct ipoib_mcast *mcast;
924 	int ret = 1;
925 
926 	spin_lock_irq(&priv->lock);
927 
928 	n = rb_first(&priv->multicast_tree);
929 
930 	while (n) {
931 		mcast = rb_entry(n, struct ipoib_mcast, rb_node);
932 
933 		if (memcmp(iter->mgid.raw, mcast->mcmember.mgid.raw,
934 			   sizeof (union ib_gid)) < 0) {
935 			iter->mgid      = mcast->mcmember.mgid;
936 			iter->created   = mcast->created;
937 			iter->queuelen  = skb_queue_len(&mcast->pkt_queue);
938 			iter->complete  = !!mcast->ah;
939 			iter->send_only = !!(mcast->flags & (1 << IPOIB_MCAST_FLAG_SENDONLY));
940 
941 			ret = 0;
942 
943 			break;
944 		}
945 
946 		n = rb_next(n);
947 	}
948 
949 	spin_unlock_irq(&priv->lock);
950 
951 	return ret;
952 }
953 
954 void ipoib_mcast_iter_read(struct ipoib_mcast_iter *iter,
955 			   union ib_gid *mgid,
956 			   unsigned long *created,
957 			   unsigned int *queuelen,
958 			   unsigned int *complete,
959 			   unsigned int *send_only)
960 {
961 	*mgid      = iter->mgid;
962 	*created   = iter->created;
963 	*queuelen  = iter->queuelen;
964 	*complete  = iter->complete;
965 	*send_only = iter->send_only;
966 }
967 
968 #endif /* CONFIG_INFINIBAND_IPOIB_DEBUG */
969