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