xref: /openbmc/linux/drivers/infiniband/ulp/ipoib/ipoib_main.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * Copyright (c) 2004 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  * $Id: ipoib_main.c 1377 2004-12-23 19:57:12Z roland $
35  */
36 
37 #include "ipoib.h"
38 
39 #include <linux/module.h>
40 
41 #include <linux/init.h>
42 #include <linux/slab.h>
43 #include <linux/kernel.h>
44 
45 #include <linux/if_arp.h>	/* For ARPHRD_xxx */
46 
47 #include <linux/ip.h>
48 #include <linux/in.h>
49 
50 #include <net/dst.h>
51 
52 MODULE_AUTHOR("Roland Dreier");
53 MODULE_DESCRIPTION("IP-over-InfiniBand net driver");
54 MODULE_LICENSE("Dual BSD/GPL");
55 
56 int ipoib_sendq_size __read_mostly = IPOIB_TX_RING_SIZE;
57 int ipoib_recvq_size __read_mostly = IPOIB_RX_RING_SIZE;
58 
59 module_param_named(send_queue_size, ipoib_sendq_size, int, 0444);
60 MODULE_PARM_DESC(send_queue_size, "Number of descriptors in send queue");
61 module_param_named(recv_queue_size, ipoib_recvq_size, int, 0444);
62 MODULE_PARM_DESC(recv_queue_size, "Number of descriptors in receive queue");
63 
64 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
65 int ipoib_debug_level;
66 
67 module_param_named(debug_level, ipoib_debug_level, int, 0644);
68 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0");
69 #endif
70 
71 struct ipoib_path_iter {
72 	struct net_device *dev;
73 	struct ipoib_path  path;
74 };
75 
76 static const u8 ipv4_bcast_addr[] = {
77 	0x00, 0xff, 0xff, 0xff,
78 	0xff, 0x12, 0x40, 0x1b,	0x00, 0x00, 0x00, 0x00,
79 	0x00, 0x00, 0x00, 0x00,	0xff, 0xff, 0xff, 0xff
80 };
81 
82 struct workqueue_struct *ipoib_workqueue;
83 
84 struct ib_sa_client ipoib_sa_client;
85 
86 static void ipoib_add_one(struct ib_device *device);
87 static void ipoib_remove_one(struct ib_device *device);
88 
89 static struct ib_client ipoib_client = {
90 	.name   = "ipoib",
91 	.add    = ipoib_add_one,
92 	.remove = ipoib_remove_one
93 };
94 
95 int ipoib_open(struct net_device *dev)
96 {
97 	struct ipoib_dev_priv *priv = netdev_priv(dev);
98 
99 	ipoib_dbg(priv, "bringing up interface\n");
100 
101 	napi_enable(&priv->napi);
102 	set_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags);
103 
104 	if (ipoib_pkey_dev_delay_open(dev))
105 		return 0;
106 
107 	if (ipoib_ib_dev_open(dev)) {
108 		napi_disable(&priv->napi);
109 		return -EINVAL;
110 	}
111 
112 	if (ipoib_ib_dev_up(dev)) {
113 		ipoib_ib_dev_stop(dev, 1);
114 		napi_disable(&priv->napi);
115 		return -EINVAL;
116 	}
117 
118 	if (!test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags)) {
119 		struct ipoib_dev_priv *cpriv;
120 
121 		/* Bring up any child interfaces too */
122 		mutex_lock(&priv->vlan_mutex);
123 		list_for_each_entry(cpriv, &priv->child_intfs, list) {
124 			int flags;
125 
126 			flags = cpriv->dev->flags;
127 			if (flags & IFF_UP)
128 				continue;
129 
130 			dev_change_flags(cpriv->dev, flags | IFF_UP);
131 		}
132 		mutex_unlock(&priv->vlan_mutex);
133 	}
134 
135 	netif_start_queue(dev);
136 
137 	return 0;
138 }
139 
140 static int ipoib_stop(struct net_device *dev)
141 {
142 	struct ipoib_dev_priv *priv = netdev_priv(dev);
143 
144 	ipoib_dbg(priv, "stopping interface\n");
145 
146 	clear_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags);
147 	napi_disable(&priv->napi);
148 
149 	netif_stop_queue(dev);
150 
151 	clear_bit(IPOIB_FLAG_NETIF_STOPPED, &priv->flags);
152 
153 	/*
154 	 * Now flush workqueue to make sure a scheduled task doesn't
155 	 * bring our internal state back up.
156 	 */
157 	flush_workqueue(ipoib_workqueue);
158 
159 	ipoib_ib_dev_down(dev, 1);
160 	ipoib_ib_dev_stop(dev, 1);
161 
162 	if (!test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags)) {
163 		struct ipoib_dev_priv *cpriv;
164 
165 		/* Bring down any child interfaces too */
166 		mutex_lock(&priv->vlan_mutex);
167 		list_for_each_entry(cpriv, &priv->child_intfs, list) {
168 			int flags;
169 
170 			flags = cpriv->dev->flags;
171 			if (!(flags & IFF_UP))
172 				continue;
173 
174 			dev_change_flags(cpriv->dev, flags & ~IFF_UP);
175 		}
176 		mutex_unlock(&priv->vlan_mutex);
177 	}
178 
179 	return 0;
180 }
181 
182 static int ipoib_change_mtu(struct net_device *dev, int new_mtu)
183 {
184 	struct ipoib_dev_priv *priv = netdev_priv(dev);
185 
186 	/* dev->mtu > 2K ==> connected mode */
187 	if (ipoib_cm_admin_enabled(dev) && new_mtu <= IPOIB_CM_MTU) {
188 		if (new_mtu > priv->mcast_mtu)
189 			ipoib_warn(priv, "mtu > %d will cause multicast packet drops.\n",
190 				   priv->mcast_mtu);
191 		dev->mtu = new_mtu;
192 		return 0;
193 	}
194 
195 	if (new_mtu > IPOIB_PACKET_SIZE - IPOIB_ENCAP_LEN) {
196 		return -EINVAL;
197 	}
198 
199 	priv->admin_mtu = new_mtu;
200 
201 	dev->mtu = min(priv->mcast_mtu, priv->admin_mtu);
202 
203 	return 0;
204 }
205 
206 static struct ipoib_path *__path_find(struct net_device *dev, void *gid)
207 {
208 	struct ipoib_dev_priv *priv = netdev_priv(dev);
209 	struct rb_node *n = priv->path_tree.rb_node;
210 	struct ipoib_path *path;
211 	int ret;
212 
213 	while (n) {
214 		path = rb_entry(n, struct ipoib_path, rb_node);
215 
216 		ret = memcmp(gid, path->pathrec.dgid.raw,
217 			     sizeof (union ib_gid));
218 
219 		if (ret < 0)
220 			n = n->rb_left;
221 		else if (ret > 0)
222 			n = n->rb_right;
223 		else
224 			return path;
225 	}
226 
227 	return NULL;
228 }
229 
230 static int __path_add(struct net_device *dev, struct ipoib_path *path)
231 {
232 	struct ipoib_dev_priv *priv = netdev_priv(dev);
233 	struct rb_node **n = &priv->path_tree.rb_node;
234 	struct rb_node *pn = NULL;
235 	struct ipoib_path *tpath;
236 	int ret;
237 
238 	while (*n) {
239 		pn = *n;
240 		tpath = rb_entry(pn, struct ipoib_path, rb_node);
241 
242 		ret = memcmp(path->pathrec.dgid.raw, tpath->pathrec.dgid.raw,
243 			     sizeof (union ib_gid));
244 		if (ret < 0)
245 			n = &pn->rb_left;
246 		else if (ret > 0)
247 			n = &pn->rb_right;
248 		else
249 			return -EEXIST;
250 	}
251 
252 	rb_link_node(&path->rb_node, pn, n);
253 	rb_insert_color(&path->rb_node, &priv->path_tree);
254 
255 	list_add_tail(&path->list, &priv->path_list);
256 
257 	return 0;
258 }
259 
260 static void path_free(struct net_device *dev, struct ipoib_path *path)
261 {
262 	struct ipoib_dev_priv *priv = netdev_priv(dev);
263 	struct ipoib_neigh *neigh, *tn;
264 	struct sk_buff *skb;
265 	unsigned long flags;
266 
267 	while ((skb = __skb_dequeue(&path->queue)))
268 		dev_kfree_skb_irq(skb);
269 
270 	spin_lock_irqsave(&priv->lock, flags);
271 
272 	list_for_each_entry_safe(neigh, tn, &path->neigh_list, list) {
273 		/*
274 		 * It's safe to call ipoib_put_ah() inside priv->lock
275 		 * here, because we know that path->ah will always
276 		 * hold one more reference, so ipoib_put_ah() will
277 		 * never do more than decrement the ref count.
278 		 */
279 		if (neigh->ah)
280 			ipoib_put_ah(neigh->ah);
281 
282 		ipoib_neigh_free(dev, neigh);
283 	}
284 
285 	spin_unlock_irqrestore(&priv->lock, flags);
286 
287 	if (path->ah)
288 		ipoib_put_ah(path->ah);
289 
290 	kfree(path);
291 }
292 
293 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG
294 
295 struct ipoib_path_iter *ipoib_path_iter_init(struct net_device *dev)
296 {
297 	struct ipoib_path_iter *iter;
298 
299 	iter = kmalloc(sizeof *iter, GFP_KERNEL);
300 	if (!iter)
301 		return NULL;
302 
303 	iter->dev = dev;
304 	memset(iter->path.pathrec.dgid.raw, 0, 16);
305 
306 	if (ipoib_path_iter_next(iter)) {
307 		kfree(iter);
308 		return NULL;
309 	}
310 
311 	return iter;
312 }
313 
314 int ipoib_path_iter_next(struct ipoib_path_iter *iter)
315 {
316 	struct ipoib_dev_priv *priv = netdev_priv(iter->dev);
317 	struct rb_node *n;
318 	struct ipoib_path *path;
319 	int ret = 1;
320 
321 	spin_lock_irq(&priv->lock);
322 
323 	n = rb_first(&priv->path_tree);
324 
325 	while (n) {
326 		path = rb_entry(n, struct ipoib_path, rb_node);
327 
328 		if (memcmp(iter->path.pathrec.dgid.raw, path->pathrec.dgid.raw,
329 			   sizeof (union ib_gid)) < 0) {
330 			iter->path = *path;
331 			ret = 0;
332 			break;
333 		}
334 
335 		n = rb_next(n);
336 	}
337 
338 	spin_unlock_irq(&priv->lock);
339 
340 	return ret;
341 }
342 
343 void ipoib_path_iter_read(struct ipoib_path_iter *iter,
344 			  struct ipoib_path *path)
345 {
346 	*path = iter->path;
347 }
348 
349 #endif /* CONFIG_INFINIBAND_IPOIB_DEBUG */
350 
351 void ipoib_flush_paths(struct net_device *dev)
352 {
353 	struct ipoib_dev_priv *priv = netdev_priv(dev);
354 	struct ipoib_path *path, *tp;
355 	LIST_HEAD(remove_list);
356 
357 	spin_lock_irq(&priv->tx_lock);
358 	spin_lock(&priv->lock);
359 
360 	list_splice(&priv->path_list, &remove_list);
361 	INIT_LIST_HEAD(&priv->path_list);
362 
363 	list_for_each_entry(path, &remove_list, list)
364 		rb_erase(&path->rb_node, &priv->path_tree);
365 
366 	list_for_each_entry_safe(path, tp, &remove_list, list) {
367 		if (path->query)
368 			ib_sa_cancel_query(path->query_id, path->query);
369 		spin_unlock(&priv->lock);
370 		spin_unlock_irq(&priv->tx_lock);
371 		wait_for_completion(&path->done);
372 		path_free(dev, path);
373 		spin_lock_irq(&priv->tx_lock);
374 		spin_lock(&priv->lock);
375 	}
376 	spin_unlock(&priv->lock);
377 	spin_unlock_irq(&priv->tx_lock);
378 }
379 
380 static void path_rec_completion(int status,
381 				struct ib_sa_path_rec *pathrec,
382 				void *path_ptr)
383 {
384 	struct ipoib_path *path = path_ptr;
385 	struct net_device *dev = path->dev;
386 	struct ipoib_dev_priv *priv = netdev_priv(dev);
387 	struct ipoib_ah *ah = NULL;
388 	struct ipoib_neigh *neigh, *tn;
389 	struct sk_buff_head skqueue;
390 	struct sk_buff *skb;
391 	unsigned long flags;
392 
393 	if (!status)
394 		ipoib_dbg(priv, "PathRec LID 0x%04x for GID " IPOIB_GID_FMT "\n",
395 			  be16_to_cpu(pathrec->dlid), IPOIB_GID_ARG(pathrec->dgid));
396 	else
397 		ipoib_dbg(priv, "PathRec status %d for GID " IPOIB_GID_FMT "\n",
398 			  status, IPOIB_GID_ARG(path->pathrec.dgid));
399 
400 	skb_queue_head_init(&skqueue);
401 
402 	if (!status) {
403 		struct ib_ah_attr av;
404 
405 		if (!ib_init_ah_from_path(priv->ca, priv->port, pathrec, &av))
406 			ah = ipoib_create_ah(dev, priv->pd, &av);
407 	}
408 
409 	spin_lock_irqsave(&priv->lock, flags);
410 
411 	path->ah = ah;
412 
413 	if (ah) {
414 		path->pathrec = *pathrec;
415 
416 		ipoib_dbg(priv, "created address handle %p for LID 0x%04x, SL %d\n",
417 			  ah, be16_to_cpu(pathrec->dlid), pathrec->sl);
418 
419 		while ((skb = __skb_dequeue(&path->queue)))
420 			__skb_queue_tail(&skqueue, skb);
421 
422 		list_for_each_entry_safe(neigh, tn, &path->neigh_list, list) {
423 			kref_get(&path->ah->ref);
424 			neigh->ah = path->ah;
425 			memcpy(&neigh->dgid.raw, &path->pathrec.dgid.raw,
426 			       sizeof(union ib_gid));
427 
428 			if (ipoib_cm_enabled(dev, neigh->neighbour)) {
429 				if (!ipoib_cm_get(neigh))
430 					ipoib_cm_set(neigh, ipoib_cm_create_tx(dev,
431 									       path,
432 									       neigh));
433 				if (!ipoib_cm_get(neigh)) {
434 					list_del(&neigh->list);
435 					if (neigh->ah)
436 						ipoib_put_ah(neigh->ah);
437 					ipoib_neigh_free(dev, neigh);
438 					continue;
439 				}
440 			}
441 
442 			while ((skb = __skb_dequeue(&neigh->queue)))
443 				__skb_queue_tail(&skqueue, skb);
444 		}
445 	}
446 
447 	path->query = NULL;
448 	complete(&path->done);
449 
450 	spin_unlock_irqrestore(&priv->lock, flags);
451 
452 	while ((skb = __skb_dequeue(&skqueue))) {
453 		skb->dev = dev;
454 		if (dev_queue_xmit(skb))
455 			ipoib_warn(priv, "dev_queue_xmit failed "
456 				   "to requeue packet\n");
457 	}
458 }
459 
460 static struct ipoib_path *path_rec_create(struct net_device *dev, void *gid)
461 {
462 	struct ipoib_dev_priv *priv = netdev_priv(dev);
463 	struct ipoib_path *path;
464 
465 	path = kzalloc(sizeof *path, GFP_ATOMIC);
466 	if (!path)
467 		return NULL;
468 
469 	path->dev = dev;
470 
471 	skb_queue_head_init(&path->queue);
472 
473 	INIT_LIST_HEAD(&path->neigh_list);
474 
475 	memcpy(path->pathrec.dgid.raw, gid, sizeof (union ib_gid));
476 	path->pathrec.sgid          = priv->local_gid;
477 	path->pathrec.pkey          = cpu_to_be16(priv->pkey);
478 	path->pathrec.numb_path     = 1;
479 	path->pathrec.traffic_class = priv->broadcast->mcmember.traffic_class;
480 
481 	return path;
482 }
483 
484 static int path_rec_start(struct net_device *dev,
485 			  struct ipoib_path *path)
486 {
487 	struct ipoib_dev_priv *priv = netdev_priv(dev);
488 
489 	ipoib_dbg(priv, "Start path record lookup for " IPOIB_GID_FMT "\n",
490 		  IPOIB_GID_ARG(path->pathrec.dgid));
491 
492 	init_completion(&path->done);
493 
494 	path->query_id =
495 		ib_sa_path_rec_get(&ipoib_sa_client, priv->ca, priv->port,
496 				   &path->pathrec,
497 				   IB_SA_PATH_REC_DGID		|
498 				   IB_SA_PATH_REC_SGID		|
499 				   IB_SA_PATH_REC_NUMB_PATH	|
500 				   IB_SA_PATH_REC_TRAFFIC_CLASS |
501 				   IB_SA_PATH_REC_PKEY,
502 				   1000, GFP_ATOMIC,
503 				   path_rec_completion,
504 				   path, &path->query);
505 	if (path->query_id < 0) {
506 		ipoib_warn(priv, "ib_sa_path_rec_get failed\n");
507 		path->query = NULL;
508 		return path->query_id;
509 	}
510 
511 	return 0;
512 }
513 
514 static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
515 {
516 	struct ipoib_dev_priv *priv = netdev_priv(dev);
517 	struct ipoib_path *path;
518 	struct ipoib_neigh *neigh;
519 
520 	neigh = ipoib_neigh_alloc(skb->dst->neighbour, skb->dev);
521 	if (!neigh) {
522 		++dev->stats.tx_dropped;
523 		dev_kfree_skb_any(skb);
524 		return;
525 	}
526 
527 	/*
528 	 * We can only be called from ipoib_start_xmit, so we're
529 	 * inside tx_lock -- no need to save/restore flags.
530 	 */
531 	spin_lock(&priv->lock);
532 
533 	path = __path_find(dev, skb->dst->neighbour->ha + 4);
534 	if (!path) {
535 		path = path_rec_create(dev, skb->dst->neighbour->ha + 4);
536 		if (!path)
537 			goto err_path;
538 
539 		__path_add(dev, path);
540 	}
541 
542 	list_add_tail(&neigh->list, &path->neigh_list);
543 
544 	if (path->ah) {
545 		kref_get(&path->ah->ref);
546 		neigh->ah = path->ah;
547 		memcpy(&neigh->dgid.raw, &path->pathrec.dgid.raw,
548 		       sizeof(union ib_gid));
549 
550 		if (ipoib_cm_enabled(dev, neigh->neighbour)) {
551 			if (!ipoib_cm_get(neigh))
552 				ipoib_cm_set(neigh, ipoib_cm_create_tx(dev, path, neigh));
553 			if (!ipoib_cm_get(neigh)) {
554 				list_del(&neigh->list);
555 				if (neigh->ah)
556 					ipoib_put_ah(neigh->ah);
557 				ipoib_neigh_free(dev, neigh);
558 				goto err_drop;
559 			}
560 			if (skb_queue_len(&neigh->queue) < IPOIB_MAX_PATH_REC_QUEUE)
561 				__skb_queue_tail(&neigh->queue, skb);
562 			else {
563 				ipoib_warn(priv, "queue length limit %d. Packet drop.\n",
564 					   skb_queue_len(&neigh->queue));
565 				goto err_drop;
566 			}
567 		} else
568 			ipoib_send(dev, skb, path->ah, IPOIB_QPN(skb->dst->neighbour->ha));
569 	} else {
570 		neigh->ah  = NULL;
571 
572 		if (!path->query && path_rec_start(dev, path))
573 			goto err_list;
574 
575 		__skb_queue_tail(&neigh->queue, skb);
576 	}
577 
578 	spin_unlock(&priv->lock);
579 	return;
580 
581 err_list:
582 	list_del(&neigh->list);
583 
584 err_path:
585 	ipoib_neigh_free(dev, neigh);
586 err_drop:
587 	++dev->stats.tx_dropped;
588 	dev_kfree_skb_any(skb);
589 
590 	spin_unlock(&priv->lock);
591 }
592 
593 static void ipoib_path_lookup(struct sk_buff *skb, struct net_device *dev)
594 {
595 	struct ipoib_dev_priv *priv = netdev_priv(skb->dev);
596 
597 	/* Look up path record for unicasts */
598 	if (skb->dst->neighbour->ha[4] != 0xff) {
599 		neigh_add_path(skb, dev);
600 		return;
601 	}
602 
603 	/* Add in the P_Key for multicasts */
604 	skb->dst->neighbour->ha[8] = (priv->pkey >> 8) & 0xff;
605 	skb->dst->neighbour->ha[9] = priv->pkey & 0xff;
606 	ipoib_mcast_send(dev, skb->dst->neighbour->ha + 4, skb);
607 }
608 
609 static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
610 			     struct ipoib_pseudoheader *phdr)
611 {
612 	struct ipoib_dev_priv *priv = netdev_priv(dev);
613 	struct ipoib_path *path;
614 
615 	/*
616 	 * We can only be called from ipoib_start_xmit, so we're
617 	 * inside tx_lock -- no need to save/restore flags.
618 	 */
619 	spin_lock(&priv->lock);
620 
621 	path = __path_find(dev, phdr->hwaddr + 4);
622 	if (!path) {
623 		path = path_rec_create(dev, phdr->hwaddr + 4);
624 		if (path) {
625 			/* put pseudoheader back on for next time */
626 			skb_push(skb, sizeof *phdr);
627 			__skb_queue_tail(&path->queue, skb);
628 
629 			if (path_rec_start(dev, path)) {
630 				spin_unlock(&priv->lock);
631 				path_free(dev, path);
632 				return;
633 			} else
634 				__path_add(dev, path);
635 		} else {
636 			++dev->stats.tx_dropped;
637 			dev_kfree_skb_any(skb);
638 		}
639 
640 		spin_unlock(&priv->lock);
641 		return;
642 	}
643 
644 	if (path->ah) {
645 		ipoib_dbg(priv, "Send unicast ARP to %04x\n",
646 			  be16_to_cpu(path->pathrec.dlid));
647 
648 		ipoib_send(dev, skb, path->ah, IPOIB_QPN(phdr->hwaddr));
649 	} else if ((path->query || !path_rec_start(dev, path)) &&
650 		   skb_queue_len(&path->queue) < IPOIB_MAX_PATH_REC_QUEUE) {
651 		/* put pseudoheader back on for next time */
652 		skb_push(skb, sizeof *phdr);
653 		__skb_queue_tail(&path->queue, skb);
654 	} else {
655 		++dev->stats.tx_dropped;
656 		dev_kfree_skb_any(skb);
657 	}
658 
659 	spin_unlock(&priv->lock);
660 }
661 
662 static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
663 {
664 	struct ipoib_dev_priv *priv = netdev_priv(dev);
665 	struct ipoib_neigh *neigh;
666 	unsigned long flags;
667 
668 	if (unlikely(!spin_trylock_irqsave(&priv->tx_lock, flags)))
669 		return NETDEV_TX_LOCKED;
670 
671 	/*
672 	 * Check if our queue is stopped.  Since we have the LLTX bit
673 	 * set, we can't rely on netif_stop_queue() preventing our
674 	 * xmit function from being called with a full queue.
675 	 */
676 	if (unlikely(netif_queue_stopped(dev))) {
677 		spin_unlock_irqrestore(&priv->tx_lock, flags);
678 		return NETDEV_TX_BUSY;
679 	}
680 
681 	if (likely(skb->dst && skb->dst->neighbour)) {
682 		if (unlikely(!*to_ipoib_neigh(skb->dst->neighbour))) {
683 			ipoib_path_lookup(skb, dev);
684 			goto out;
685 		}
686 
687 		neigh = *to_ipoib_neigh(skb->dst->neighbour);
688 
689 		if (ipoib_cm_get(neigh)) {
690 			if (ipoib_cm_up(neigh)) {
691 				ipoib_cm_send(dev, skb, ipoib_cm_get(neigh));
692 				goto out;
693 			}
694 		} else if (neigh->ah) {
695 			if (unlikely((memcmp(&neigh->dgid.raw,
696 					    skb->dst->neighbour->ha + 4,
697 					    sizeof(union ib_gid))) ||
698 					 (neigh->dev != dev))) {
699 				spin_lock(&priv->lock);
700 				/*
701 				 * It's safe to call ipoib_put_ah() inside
702 				 * priv->lock here, because we know that
703 				 * path->ah will always hold one more reference,
704 				 * so ipoib_put_ah() will never do more than
705 				 * decrement the ref count.
706 				 */
707 				ipoib_put_ah(neigh->ah);
708 				list_del(&neigh->list);
709 				ipoib_neigh_free(dev, neigh);
710 				spin_unlock(&priv->lock);
711 				ipoib_path_lookup(skb, dev);
712 				goto out;
713 			}
714 
715 			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(skb->dst->neighbour->ha));
716 			goto out;
717 		}
718 
719 		if (skb_queue_len(&neigh->queue) < IPOIB_MAX_PATH_REC_QUEUE) {
720 			spin_lock(&priv->lock);
721 			__skb_queue_tail(&neigh->queue, skb);
722 			spin_unlock(&priv->lock);
723 		} else {
724 			++dev->stats.tx_dropped;
725 			dev_kfree_skb_any(skb);
726 		}
727 	} else {
728 		struct ipoib_pseudoheader *phdr =
729 			(struct ipoib_pseudoheader *) skb->data;
730 		skb_pull(skb, sizeof *phdr);
731 
732 		if (phdr->hwaddr[4] == 0xff) {
733 			/* Add in the P_Key for multicast*/
734 			phdr->hwaddr[8] = (priv->pkey >> 8) & 0xff;
735 			phdr->hwaddr[9] = priv->pkey & 0xff;
736 
737 			ipoib_mcast_send(dev, phdr->hwaddr + 4, skb);
738 		} else {
739 			/* unicast GID -- should be ARP or RARP reply */
740 
741 			if ((be16_to_cpup((__be16 *) skb->data) != ETH_P_ARP) &&
742 			    (be16_to_cpup((__be16 *) skb->data) != ETH_P_RARP)) {
743 				ipoib_warn(priv, "Unicast, no %s: type %04x, QPN %06x "
744 					   IPOIB_GID_FMT "\n",
745 					   skb->dst ? "neigh" : "dst",
746 					   be16_to_cpup((__be16 *) skb->data),
747 					   IPOIB_QPN(phdr->hwaddr),
748 					   IPOIB_GID_RAW_ARG(phdr->hwaddr + 4));
749 				dev_kfree_skb_any(skb);
750 				++dev->stats.tx_dropped;
751 				goto out;
752 			}
753 
754 			unicast_arp_send(skb, dev, phdr);
755 		}
756 	}
757 
758 out:
759 	spin_unlock_irqrestore(&priv->tx_lock, flags);
760 
761 	return NETDEV_TX_OK;
762 }
763 
764 static void ipoib_timeout(struct net_device *dev)
765 {
766 	struct ipoib_dev_priv *priv = netdev_priv(dev);
767 
768 	ipoib_warn(priv, "transmit timeout: latency %d msecs\n",
769 		   jiffies_to_msecs(jiffies - dev->trans_start));
770 	ipoib_warn(priv, "queue stopped %d, tx_head %u, tx_tail %u\n",
771 		   netif_queue_stopped(dev),
772 		   priv->tx_head, priv->tx_tail);
773 	/* XXX reset QP, etc. */
774 }
775 
776 static int ipoib_hard_header(struct sk_buff *skb,
777 			     struct net_device *dev,
778 			     unsigned short type,
779 			     const void *daddr, const void *saddr, unsigned len)
780 {
781 	struct ipoib_header *header;
782 
783 	header = (struct ipoib_header *) skb_push(skb, sizeof *header);
784 
785 	header->proto = htons(type);
786 	header->reserved = 0;
787 
788 	/*
789 	 * If we don't have a neighbour structure, stuff the
790 	 * destination address onto the front of the skb so we can
791 	 * figure out where to send the packet later.
792 	 */
793 	if ((!skb->dst || !skb->dst->neighbour) && daddr) {
794 		struct ipoib_pseudoheader *phdr =
795 			(struct ipoib_pseudoheader *) skb_push(skb, sizeof *phdr);
796 		memcpy(phdr->hwaddr, daddr, INFINIBAND_ALEN);
797 	}
798 
799 	return 0;
800 }
801 
802 static void ipoib_set_mcast_list(struct net_device *dev)
803 {
804 	struct ipoib_dev_priv *priv = netdev_priv(dev);
805 
806 	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) {
807 		ipoib_dbg(priv, "IPOIB_FLAG_OPER_UP not set");
808 		return;
809 	}
810 
811 	queue_work(ipoib_workqueue, &priv->restart_task);
812 }
813 
814 static void ipoib_neigh_cleanup(struct neighbour *n)
815 {
816 	struct ipoib_neigh *neigh;
817 	struct ipoib_dev_priv *priv = netdev_priv(n->dev);
818 	unsigned long flags;
819 	struct ipoib_ah *ah = NULL;
820 
821 	neigh = *to_ipoib_neigh(n);
822 	if (neigh) {
823 		priv = netdev_priv(neigh->dev);
824 		ipoib_dbg(priv, "neigh_destructor for bonding device: %s\n",
825 			  n->dev->name);
826 	} else
827 		return;
828 	ipoib_dbg(priv,
829 		  "neigh_cleanup for %06x " IPOIB_GID_FMT "\n",
830 		  IPOIB_QPN(n->ha),
831 		  IPOIB_GID_RAW_ARG(n->ha + 4));
832 
833 	spin_lock_irqsave(&priv->lock, flags);
834 
835 	if (neigh->ah)
836 		ah = neigh->ah;
837 	list_del(&neigh->list);
838 	ipoib_neigh_free(n->dev, neigh);
839 
840 	spin_unlock_irqrestore(&priv->lock, flags);
841 
842 	if (ah)
843 		ipoib_put_ah(ah);
844 }
845 
846 struct ipoib_neigh *ipoib_neigh_alloc(struct neighbour *neighbour,
847 				      struct net_device *dev)
848 {
849 	struct ipoib_neigh *neigh;
850 
851 	neigh = kmalloc(sizeof *neigh, GFP_ATOMIC);
852 	if (!neigh)
853 		return NULL;
854 
855 	neigh->neighbour = neighbour;
856 	neigh->dev = dev;
857 	*to_ipoib_neigh(neighbour) = neigh;
858 	skb_queue_head_init(&neigh->queue);
859 	ipoib_cm_set(neigh, NULL);
860 
861 	return neigh;
862 }
863 
864 void ipoib_neigh_free(struct net_device *dev, struct ipoib_neigh *neigh)
865 {
866 	struct sk_buff *skb;
867 	*to_ipoib_neigh(neigh->neighbour) = NULL;
868 	while ((skb = __skb_dequeue(&neigh->queue))) {
869 		++dev->stats.tx_dropped;
870 		dev_kfree_skb_any(skb);
871 	}
872 	if (ipoib_cm_get(neigh))
873 		ipoib_cm_destroy_tx(ipoib_cm_get(neigh));
874 	kfree(neigh);
875 }
876 
877 static int ipoib_neigh_setup_dev(struct net_device *dev, struct neigh_parms *parms)
878 {
879 	parms->neigh_cleanup = ipoib_neigh_cleanup;
880 
881 	return 0;
882 }
883 
884 int ipoib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
885 {
886 	struct ipoib_dev_priv *priv = netdev_priv(dev);
887 
888 	/* Allocate RX/TX "rings" to hold queued skbs */
889 	priv->rx_ring =	kzalloc(ipoib_recvq_size * sizeof *priv->rx_ring,
890 				GFP_KERNEL);
891 	if (!priv->rx_ring) {
892 		printk(KERN_WARNING "%s: failed to allocate RX ring (%d entries)\n",
893 		       ca->name, ipoib_recvq_size);
894 		goto out;
895 	}
896 
897 	priv->tx_ring = kzalloc(ipoib_sendq_size * sizeof *priv->tx_ring,
898 				GFP_KERNEL);
899 	if (!priv->tx_ring) {
900 		printk(KERN_WARNING "%s: failed to allocate TX ring (%d entries)\n",
901 		       ca->name, ipoib_sendq_size);
902 		goto out_rx_ring_cleanup;
903 	}
904 
905 	/* priv->tx_head & tx_tail are already 0 */
906 
907 	if (ipoib_ib_dev_init(dev, ca, port))
908 		goto out_tx_ring_cleanup;
909 
910 	return 0;
911 
912 out_tx_ring_cleanup:
913 	kfree(priv->tx_ring);
914 
915 out_rx_ring_cleanup:
916 	kfree(priv->rx_ring);
917 
918 out:
919 	return -ENOMEM;
920 }
921 
922 void ipoib_dev_cleanup(struct net_device *dev)
923 {
924 	struct ipoib_dev_priv *priv = netdev_priv(dev), *cpriv, *tcpriv;
925 
926 	ipoib_delete_debug_files(dev);
927 
928 	/* Delete any child interfaces first */
929 	list_for_each_entry_safe(cpriv, tcpriv, &priv->child_intfs, list) {
930 		unregister_netdev(cpriv->dev);
931 		ipoib_dev_cleanup(cpriv->dev);
932 		free_netdev(cpriv->dev);
933 	}
934 
935 	ipoib_ib_dev_cleanup(dev);
936 
937 	kfree(priv->rx_ring);
938 	kfree(priv->tx_ring);
939 
940 	priv->rx_ring = NULL;
941 	priv->tx_ring = NULL;
942 }
943 
944 static const struct header_ops ipoib_header_ops = {
945 	.create	= ipoib_hard_header,
946 };
947 
948 static void ipoib_setup(struct net_device *dev)
949 {
950 	struct ipoib_dev_priv *priv = netdev_priv(dev);
951 
952 	dev->open 		 = ipoib_open;
953 	dev->stop 		 = ipoib_stop;
954 	dev->change_mtu 	 = ipoib_change_mtu;
955 	dev->hard_start_xmit 	 = ipoib_start_xmit;
956 	dev->tx_timeout 	 = ipoib_timeout;
957 	dev->header_ops 	 = &ipoib_header_ops;
958 	dev->set_multicast_list  = ipoib_set_mcast_list;
959 	dev->neigh_setup         = ipoib_neigh_setup_dev;
960 
961 	netif_napi_add(dev, &priv->napi, ipoib_poll, 100);
962 
963 	dev->watchdog_timeo 	 = HZ;
964 
965 	dev->flags              |= IFF_BROADCAST | IFF_MULTICAST;
966 
967 	/*
968 	 * We add in INFINIBAND_ALEN to allow for the destination
969 	 * address "pseudoheader" for skbs without neighbour struct.
970 	 */
971 	dev->hard_header_len 	 = IPOIB_ENCAP_LEN + INFINIBAND_ALEN;
972 	dev->addr_len 		 = INFINIBAND_ALEN;
973 	dev->type 		 = ARPHRD_INFINIBAND;
974 	dev->tx_queue_len 	 = ipoib_sendq_size * 2;
975 	dev->features            = NETIF_F_VLAN_CHALLENGED | NETIF_F_LLTX;
976 
977 	/* MTU will be reset when mcast join happens */
978 	dev->mtu 		 = IPOIB_PACKET_SIZE - IPOIB_ENCAP_LEN;
979 	priv->mcast_mtu 	 = priv->admin_mtu = dev->mtu;
980 
981 	memcpy(dev->broadcast, ipv4_bcast_addr, INFINIBAND_ALEN);
982 
983 	netif_carrier_off(dev);
984 
985 	priv->dev = dev;
986 
987 	spin_lock_init(&priv->lock);
988 	spin_lock_init(&priv->tx_lock);
989 
990 	mutex_init(&priv->mcast_mutex);
991 	mutex_init(&priv->vlan_mutex);
992 
993 	INIT_LIST_HEAD(&priv->path_list);
994 	INIT_LIST_HEAD(&priv->child_intfs);
995 	INIT_LIST_HEAD(&priv->dead_ahs);
996 	INIT_LIST_HEAD(&priv->multicast_list);
997 
998 	INIT_DELAYED_WORK(&priv->pkey_poll_task, ipoib_pkey_poll);
999 	INIT_WORK(&priv->pkey_event_task, ipoib_pkey_event);
1000 	INIT_DELAYED_WORK(&priv->mcast_task,   ipoib_mcast_join_task);
1001 	INIT_WORK(&priv->flush_task,   ipoib_ib_dev_flush);
1002 	INIT_WORK(&priv->restart_task, ipoib_mcast_restart_task);
1003 	INIT_DELAYED_WORK(&priv->ah_reap_task, ipoib_reap_ah);
1004 }
1005 
1006 struct ipoib_dev_priv *ipoib_intf_alloc(const char *name)
1007 {
1008 	struct net_device *dev;
1009 
1010 	dev = alloc_netdev((int) sizeof (struct ipoib_dev_priv), name,
1011 			   ipoib_setup);
1012 	if (!dev)
1013 		return NULL;
1014 
1015 	return netdev_priv(dev);
1016 }
1017 
1018 static ssize_t show_pkey(struct device *dev,
1019 			 struct device_attribute *attr, char *buf)
1020 {
1021 	struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(dev));
1022 
1023 	return sprintf(buf, "0x%04x\n", priv->pkey);
1024 }
1025 static DEVICE_ATTR(pkey, S_IRUGO, show_pkey, NULL);
1026 
1027 static ssize_t show_umcast(struct device *dev,
1028 			   struct device_attribute *attr, char *buf)
1029 {
1030 	struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(dev));
1031 
1032 	return sprintf(buf, "%d\n", test_bit(IPOIB_FLAG_UMCAST, &priv->flags));
1033 }
1034 
1035 static ssize_t set_umcast(struct device *dev,
1036 			  struct device_attribute *attr,
1037 			  const char *buf, size_t count)
1038 {
1039 	struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(dev));
1040 	unsigned long umcast_val = simple_strtoul(buf, NULL, 0);
1041 
1042 	if (umcast_val > 0) {
1043 		set_bit(IPOIB_FLAG_UMCAST, &priv->flags);
1044 		ipoib_warn(priv, "ignoring multicast groups joined directly "
1045 				"by userspace\n");
1046 	} else
1047 		clear_bit(IPOIB_FLAG_UMCAST, &priv->flags);
1048 
1049 	return count;
1050 }
1051 static DEVICE_ATTR(umcast, S_IWUSR | S_IRUGO, show_umcast, set_umcast);
1052 
1053 int ipoib_add_umcast_attr(struct net_device *dev)
1054 {
1055 	return device_create_file(&dev->dev, &dev_attr_umcast);
1056 }
1057 
1058 static ssize_t create_child(struct device *dev,
1059 			    struct device_attribute *attr,
1060 			    const char *buf, size_t count)
1061 {
1062 	int pkey;
1063 	int ret;
1064 
1065 	if (sscanf(buf, "%i", &pkey) != 1)
1066 		return -EINVAL;
1067 
1068 	if (pkey < 0 || pkey > 0xffff)
1069 		return -EINVAL;
1070 
1071 	/*
1072 	 * Set the full membership bit, so that we join the right
1073 	 * broadcast group, etc.
1074 	 */
1075 	pkey |= 0x8000;
1076 
1077 	ret = ipoib_vlan_add(to_net_dev(dev), pkey);
1078 
1079 	return ret ? ret : count;
1080 }
1081 static DEVICE_ATTR(create_child, S_IWUGO, NULL, create_child);
1082 
1083 static ssize_t delete_child(struct device *dev,
1084 			    struct device_attribute *attr,
1085 			    const char *buf, size_t count)
1086 {
1087 	int pkey;
1088 	int ret;
1089 
1090 	if (sscanf(buf, "%i", &pkey) != 1)
1091 		return -EINVAL;
1092 
1093 	if (pkey < 0 || pkey > 0xffff)
1094 		return -EINVAL;
1095 
1096 	ret = ipoib_vlan_delete(to_net_dev(dev), pkey);
1097 
1098 	return ret ? ret : count;
1099 
1100 }
1101 static DEVICE_ATTR(delete_child, S_IWUGO, NULL, delete_child);
1102 
1103 int ipoib_add_pkey_attr(struct net_device *dev)
1104 {
1105 	return device_create_file(&dev->dev, &dev_attr_pkey);
1106 }
1107 
1108 static struct net_device *ipoib_add_port(const char *format,
1109 					 struct ib_device *hca, u8 port)
1110 {
1111 	struct ipoib_dev_priv *priv;
1112 	int result = -ENOMEM;
1113 
1114 	priv = ipoib_intf_alloc(format);
1115 	if (!priv)
1116 		goto alloc_mem_failed;
1117 
1118 	SET_NETDEV_DEV(priv->dev, hca->dma_device);
1119 
1120 	result = ib_query_pkey(hca, port, 0, &priv->pkey);
1121 	if (result) {
1122 		printk(KERN_WARNING "%s: ib_query_pkey port %d failed (ret = %d)\n",
1123 		       hca->name, port, result);
1124 		goto device_init_failed;
1125 	}
1126 
1127 	/*
1128 	 * Set the full membership bit, so that we join the right
1129 	 * broadcast group, etc.
1130 	 */
1131 	priv->pkey |= 0x8000;
1132 
1133 	priv->dev->broadcast[8] = priv->pkey >> 8;
1134 	priv->dev->broadcast[9] = priv->pkey & 0xff;
1135 
1136 	result = ib_query_gid(hca, port, 0, &priv->local_gid);
1137 	if (result) {
1138 		printk(KERN_WARNING "%s: ib_query_gid port %d failed (ret = %d)\n",
1139 		       hca->name, port, result);
1140 		goto device_init_failed;
1141 	} else
1142 		memcpy(priv->dev->dev_addr + 4, priv->local_gid.raw, sizeof (union ib_gid));
1143 
1144 
1145 	result = ipoib_dev_init(priv->dev, hca, port);
1146 	if (result < 0) {
1147 		printk(KERN_WARNING "%s: failed to initialize port %d (ret = %d)\n",
1148 		       hca->name, port, result);
1149 		goto device_init_failed;
1150 	}
1151 
1152 	INIT_IB_EVENT_HANDLER(&priv->event_handler,
1153 			      priv->ca, ipoib_event);
1154 	result = ib_register_event_handler(&priv->event_handler);
1155 	if (result < 0) {
1156 		printk(KERN_WARNING "%s: ib_register_event_handler failed for "
1157 		       "port %d (ret = %d)\n",
1158 		       hca->name, port, result);
1159 		goto event_failed;
1160 	}
1161 
1162 	result = register_netdev(priv->dev);
1163 	if (result) {
1164 		printk(KERN_WARNING "%s: couldn't register ipoib port %d; error %d\n",
1165 		       hca->name, port, result);
1166 		goto register_failed;
1167 	}
1168 
1169 	ipoib_create_debug_files(priv->dev);
1170 
1171 	if (ipoib_cm_add_mode_attr(priv->dev))
1172 		goto sysfs_failed;
1173 	if (ipoib_add_pkey_attr(priv->dev))
1174 		goto sysfs_failed;
1175 	if (ipoib_add_umcast_attr(priv->dev))
1176 		goto sysfs_failed;
1177 	if (device_create_file(&priv->dev->dev, &dev_attr_create_child))
1178 		goto sysfs_failed;
1179 	if (device_create_file(&priv->dev->dev, &dev_attr_delete_child))
1180 		goto sysfs_failed;
1181 
1182 	return priv->dev;
1183 
1184 sysfs_failed:
1185 	ipoib_delete_debug_files(priv->dev);
1186 	unregister_netdev(priv->dev);
1187 
1188 register_failed:
1189 	ib_unregister_event_handler(&priv->event_handler);
1190 	flush_scheduled_work();
1191 
1192 event_failed:
1193 	ipoib_dev_cleanup(priv->dev);
1194 
1195 device_init_failed:
1196 	free_netdev(priv->dev);
1197 
1198 alloc_mem_failed:
1199 	return ERR_PTR(result);
1200 }
1201 
1202 static void ipoib_add_one(struct ib_device *device)
1203 {
1204 	struct list_head *dev_list;
1205 	struct net_device *dev;
1206 	struct ipoib_dev_priv *priv;
1207 	int s, e, p;
1208 
1209 	if (rdma_node_get_transport(device->node_type) != RDMA_TRANSPORT_IB)
1210 		return;
1211 
1212 	dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
1213 	if (!dev_list)
1214 		return;
1215 
1216 	INIT_LIST_HEAD(dev_list);
1217 
1218 	if (device->node_type == RDMA_NODE_IB_SWITCH) {
1219 		s = 0;
1220 		e = 0;
1221 	} else {
1222 		s = 1;
1223 		e = device->phys_port_cnt;
1224 	}
1225 
1226 	for (p = s; p <= e; ++p) {
1227 		dev = ipoib_add_port("ib%d", device, p);
1228 		if (!IS_ERR(dev)) {
1229 			priv = netdev_priv(dev);
1230 			list_add_tail(&priv->list, dev_list);
1231 		}
1232 	}
1233 
1234 	ib_set_client_data(device, &ipoib_client, dev_list);
1235 }
1236 
1237 static void ipoib_remove_one(struct ib_device *device)
1238 {
1239 	struct ipoib_dev_priv *priv, *tmp;
1240 	struct list_head *dev_list;
1241 
1242 	if (rdma_node_get_transport(device->node_type) != RDMA_TRANSPORT_IB)
1243 		return;
1244 
1245 	dev_list = ib_get_client_data(device, &ipoib_client);
1246 
1247 	list_for_each_entry_safe(priv, tmp, dev_list, list) {
1248 		ib_unregister_event_handler(&priv->event_handler);
1249 		flush_scheduled_work();
1250 
1251 		unregister_netdev(priv->dev);
1252 		ipoib_dev_cleanup(priv->dev);
1253 		free_netdev(priv->dev);
1254 	}
1255 
1256 	kfree(dev_list);
1257 }
1258 
1259 static int __init ipoib_init_module(void)
1260 {
1261 	int ret;
1262 
1263 	ipoib_recvq_size = roundup_pow_of_two(ipoib_recvq_size);
1264 	ipoib_recvq_size = min(ipoib_recvq_size, IPOIB_MAX_QUEUE_SIZE);
1265 	ipoib_recvq_size = max(ipoib_recvq_size, IPOIB_MIN_QUEUE_SIZE);
1266 
1267 	ipoib_sendq_size = roundup_pow_of_two(ipoib_sendq_size);
1268 	ipoib_sendq_size = min(ipoib_sendq_size, IPOIB_MAX_QUEUE_SIZE);
1269 	ipoib_sendq_size = max(ipoib_sendq_size, IPOIB_MIN_QUEUE_SIZE);
1270 
1271 	ret = ipoib_register_debugfs();
1272 	if (ret)
1273 		return ret;
1274 
1275 	/*
1276 	 * We create our own workqueue mainly because we want to be
1277 	 * able to flush it when devices are being removed.  We can't
1278 	 * use schedule_work()/flush_scheduled_work() because both
1279 	 * unregister_netdev() and linkwatch_event take the rtnl lock,
1280 	 * so flush_scheduled_work() can deadlock during device
1281 	 * removal.
1282 	 */
1283 	ipoib_workqueue = create_singlethread_workqueue("ipoib");
1284 	if (!ipoib_workqueue) {
1285 		ret = -ENOMEM;
1286 		goto err_fs;
1287 	}
1288 
1289 	ib_sa_register_client(&ipoib_sa_client);
1290 
1291 	ret = ib_register_client(&ipoib_client);
1292 	if (ret)
1293 		goto err_sa;
1294 
1295 	return 0;
1296 
1297 err_sa:
1298 	ib_sa_unregister_client(&ipoib_sa_client);
1299 	destroy_workqueue(ipoib_workqueue);
1300 
1301 err_fs:
1302 	ipoib_unregister_debugfs();
1303 
1304 	return ret;
1305 }
1306 
1307 static void __exit ipoib_cleanup_module(void)
1308 {
1309 	ib_unregister_client(&ipoib_client);
1310 	ib_sa_unregister_client(&ipoib_sa_client);
1311 	ipoib_unregister_debugfs();
1312 	destroy_workqueue(ipoib_workqueue);
1313 }
1314 
1315 module_init(ipoib_init_module);
1316 module_exit(ipoib_cleanup_module);
1317