aboutsummaryrefslogtreecommitdiffstats
path: root/net/core/dev_addr_lists.c
blob: 277faef9148d0053bc6987ae67e73571d49a4d99 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
/*
 * net/core/dev_addr_lists.c - Functions for handling net device lists
 * Copyright (c) 2010 Jiri Pirko <jpirko@redhat.com>
 *
 * This file contains functions for working with unicast, multicast and device
 * addresses lists.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/export.h>
#include <linux/list.h>
#include <linux/proc_fs.h>

/*
 * General list handling functions
 */

static int __hw_addr_add_ex(struct netdev_hw_addr_list *list,
			    unsigned char *addr, int addr_len,
			    unsigned char addr_type, bool global)
{
	struct netdev_hw_addr *ha;
	int alloc_size;

	if (addr_len > MAX_ADDR_LEN)
		return -EINVAL;

	list_for_each_entry(ha, &list->list, list) {
		if (!memcmp(ha->addr, addr, addr_len) &&
		    ha->type == addr_type) {
			if (global) {
				/* check if addr is already used as global */
				if (ha->global_use)
					return 0;
				else
					ha->global_use = true;
			}
			ha->refcount++;
			return 0;
		}
	}


	alloc_size = sizeof(*ha);
	if (alloc_size < L1_CACHE_BYTES)
		alloc_size = L1_CACHE_BYTES;
	ha = kmalloc(alloc_size, GFP_ATOMIC);
	if (!ha)
		return -ENOMEM;
	memcpy(ha->addr, addr, addr_len);
	ha->type = addr_type;
	ha->refcount = 1;
	ha->global_use = global;
	ha->synced = false;
	list_add_tail_rcu(&ha->list, &list->list);
	list->count++;
	return 0;
}

static int __hw_addr_add(struct netdev_hw_addr_list *list, unsigned char *addr,
			 int addr_len, unsigned char addr_type)
{
	return __hw_addr_add_ex(list, addr, addr_len, addr_type, false);
}

static int __hw_addr_del_ex(struct netdev_hw_addr_list *list,
			    unsigned char *addr, int addr_len,
			    unsigned char addr_type, bool global)
{
	struct netdev_hw_addr *ha;

	list_for_each_entry(ha, &list->list, list) {
		if (!memcmp(ha->addr, addr, addr_len) &&
		    (ha->type == addr_type || !addr_type)) {
			if (global) {
				if (!ha->global_use)
					break;
				else
					ha->global_use = false;
			}
			if (--ha->refcount)
				return 0;
			list_del_rcu(&ha->list);
			kfree_rcu(ha, rcu_head);
			list->count--;
			return 0;
		}
	}
	return -ENOENT;
}

static int __hw_addr_del(struct netdev_hw_addr_list *list, unsigned char *addr,
			 int addr_len, unsigned char addr_type)
{
	return __hw_addr_del_ex(list, addr, addr_len, addr_type, false);
}

int __hw_addr_add_multiple(struct netdev_hw_addr_list *to_list,
			   struct netdev_hw_addr_list *from_list,
			   int addr_len, unsigned char addr_type)
{
	int err;
	struct netdev_hw_addr *ha, *ha2;
	unsigned char type;

	list_for_each_entry(ha, &from_list->list, list) {
		type = addr_type ? addr_type : ha->type;
		err = __hw_addr_add(to_list, ha->addr, addr_len, type);
		if (err)
			goto unroll;
	}
	return 0;

unroll:
	list_for_each_entry(ha2, &from_list->list, list) {
		if (ha2 == ha)
			break;
		type = addr_type ? addr_type : ha2->type;
		__hw_addr_del(to_list, ha2->addr, addr_len, type);
	}
	return err;
}
EXPORT_SYMBOL(__hw_addr_add_multiple);

void __hw_addr_del_multiple(struct netdev_hw_addr_list *to_list,
			    struct netdev_hw_addr_list *from_list,
			    int addr_len, unsigned char addr_type)
{
	struct netdev_hw_addr *ha;
	unsigned char type;

	list_for_each_entry(ha, &from_list->list, list) {
		type = addr_type ? addr_type : ha->type;
		__hw_addr_del(to_list, ha->addr, addr_len, type);
	}
}
EXPORT_SYMBOL(__hw_addr_del_multiple);

int __hw_addr_sync(struct netdev_hw_addr_list *to_list,
		   struct netdev_hw_addr_list *from_list,
		   int addr_len)
{
	int err = 0;
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
		if (!ha->synced) {
			err = __hw_addr_add(to_list, ha->addr,
					    addr_len, ha->type);
			if (err)
				break;
			ha->synced = true;
			ha->refcount++;
		} else if (ha->refcount == 1) {
			__hw_addr_del(to_list, ha->addr, addr_len, ha->type);
			__hw_addr_del(from_list, ha->addr, addr_len, ha->type);
		}
	}
	return err;
}
EXPORT_SYMBOL(__hw_addr_sync);

void __hw_addr_unsync(struct netdev_hw_addr_list *to_list,
		      struct netdev_hw_addr_list *from_list,
		      int addr_len)
{
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
		if (ha->synced) {
			__hw_addr_del(to_list, ha->addr,
				      addr_len, ha->type);
			ha->synced = false;
			__hw_addr_del(from_list, ha->addr,
				      addr_len, ha->type);
		}
	}
}
EXPORT_SYMBOL(__hw_addr_unsync);

void __hw_addr_flush(struct netdev_hw_addr_list *list)
{
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &list->list, list) {
		list_del_rcu(&ha->list);
		kfree_rcu(ha, rcu_head);
	}
	list->count = 0;
}
EXPORT_SYMBOL(__hw_addr_flush);

void __hw_addr_init(struct netdev_hw_addr_list *list)
{
	INIT_LIST_HEAD(&list->list);
	list->count = 0;
}
EXPORT_SYMBOL(__hw_addr_init);

/*
 * Device addresses handling functions
 */

/**
 *	dev_addr_flush - Flush device address list
 *	@dev: device
 *
 *	Flush device address list and reset ->dev_addr.
 *
 *	The caller must hold the rtnl_mutex.
 */
void dev_addr_flush(struct net_device *dev)
{
	/* rtnl_mutex must be held here */

	__hw_addr_flush(&dev->dev_addrs);
	dev->dev_addr = NULL;
}
EXPORT_SYMBOL(dev_addr_flush);

/**
 *	dev_addr_init - Init device address list
 *	@dev: device
 *
 *	Init device address list and create the first element,
 *	used by ->dev_addr.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_init(struct net_device *dev)
{
	unsigned char addr[MAX_ADDR_LEN];
	struct netdev_hw_addr *ha;
	int err;

	/* rtnl_mutex must be held here */

	__hw_addr_init(&dev->dev_addrs);
	memset(addr, 0, sizeof(addr));
	err = __hw_addr_add(&dev->dev_addrs, addr, sizeof(addr),
			    NETDEV_HW_ADDR_T_LAN);
	if (!err) {
		/*
		 * Get the first (previously created) address from the list
		 * and set dev_addr pointer to this location.
		 */
		ha = list_first_entry(&dev->dev_addrs.list,
				      struct netdev_hw_addr, list);
		dev->dev_addr = ha->addr;
	}
	return err;
}
EXPORT_SYMBOL(dev_addr_init);

/**
 *	dev_addr_add - Add a device address
 *	@dev: device
 *	@addr: address to add
 *	@addr_type: address type
 *
 *	Add a device address to the device or increase the reference count if
 *	it already exists.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_add(struct net_device *dev, unsigned char *addr,
		 unsigned char addr_type)
{
	int err;

	ASSERT_RTNL();

	err = __hw_addr_add(&dev->dev_addrs, addr, dev->addr_len, addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_add);

/**
 *	dev_addr_del - Release a device address.
 *	@dev: device
 *	@addr: address to delete
 *	@addr_type: address type
 *
 *	Release reference to a device address and remove it from the device
 *	if the reference count drops to zero.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_del(struct net_device *dev, unsigned char *addr,
		 unsigned char addr_type)
{
	int err;
	struct netdev_hw_addr *ha;

	ASSERT_RTNL();

	/*
	 * We can not remove the first address from the list because
	 * dev->dev_addr points to that.
	 */
	ha = list_first_entry(&dev->dev_addrs.list,
			      struct netdev_hw_addr, list);
	if (ha->addr == dev->dev_addr && ha->refcount == 1)
		return -ENOENT;

	err = __hw_addr_del(&dev->dev_addrs, addr, dev->addr_len,
			    addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_del);

/**
 *	dev_addr_add_multiple - Add device addresses from another device
 *	@to_dev: device to which addresses will be added
 *	@from_dev: device from which addresses will be added
 *	@addr_type: address type - 0 means type will be used from from_dev
 *
 *	Add device addresses of the one device to another.
 **
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_add_multiple(struct net_device *to_dev,
			  struct net_device *from_dev,
			  unsigned char addr_type)
{
	int err;

	ASSERT_RTNL();

	if (from_dev->addr_len != to_dev->addr_len)
		return -EINVAL;
	err = __hw_addr_add_multiple(&to_dev->dev_addrs, &from_dev->dev_addrs,
				     to_dev->addr_len, addr_type);
	if (!err)
		call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev);
	return err;
}
EXPORT_SYMBOL(dev_addr_add_multiple);

/**
 *	dev_addr_del_multiple - Delete device addresses by another device
 *	@to_dev: device where the addresses will be deleted
 *	@from_dev: device supplying the addresses to be deleted
 *	@addr_type: address type - 0 means type will be used from from_dev
 *
 *	Deletes addresses in to device by the list of addresses in from device.
 *
 *	The caller must hold the rtnl_mutex.
 */
int dev_addr_del_multiple(struct net_device *to_dev,
			  struct net_device *from_dev,
			  unsigned char addr_type)
{
	ASSERT_RTNL();

	if (from_dev->addr_len != to_dev->addr_len)
		return -EINVAL;
	__hw_addr_del_multiple(&to_dev->dev_addrs, &from_dev->dev_addrs,
			       to_dev->addr_len, addr_type);
	call_netdevice_notifiers(NETDEV_CHANGEADDR, to_dev);
	return 0;
}
EXPORT_SYMBOL(dev_addr_del_multiple);

/*
 * Unicast list handling functions
 */

/**
 *	dev_uc_add - Add a secondary unicast address
 *	@dev: device
 *	@addr: address to add
 *
 *	Add a secondary unicast address to the device or increase
 *	the reference count if it already exists.
 */
int dev_uc_add(struct net_device *dev, unsigned char *addr)
{
	int err;

	netif_addr_lock_bh(dev);
	err = __hw_addr_add(&dev->uc, addr, dev->addr_len,
			    NETDEV_HW_ADDR_T_UNICAST);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_uc_add);

/**
 *	dev_uc_del - Release secondary unicast address.
 *	@dev: device
 *	@addr: address to delete
 *
 *	Release reference to a secondary unicast address and remove it
 *	from the device if the reference count drops to zero.
 */
int dev_uc_del(struct net_device *dev, unsigned char *addr)
{
	int err;

	netif_addr_lock_bh(dev);
	err = __hw_addr_del(&dev->uc, addr, dev->addr_len,
			    NETDEV_HW_ADDR_T_UNICAST);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_uc_del);

/**
 *	dev_uc_sync - Synchronize device's unicast list to another device
 *	@to: destination device
 *	@from: source device
 *
 *	Add newly added addresses to the destination device and release
 *	addresses that have no users left. The source device must be
 *	locked by netif_tx_lock_bh.
 *
 *	This function is intended to be called from the dev->set_rx_mode
 *	function of layered software devices.
 */
int dev_uc_sync(struct net_device *to, struct net_device *from)
{
	int err = 0;

	if (to->addr_len != from->addr_len)
		return -EINVAL;

	netif_addr_lock_bh(to);
	err = __hw_addr_sync(&to->uc, &from->uc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock_bh(to);
	return err;
}
EXPORT_SYMBOL(dev_uc_sync);

/**
 *	dev_uc_unsync - Remove synchronized addresses from the destination device
 *	@to: destination device
 *	@from: source device
 *
 *	Remove all addresses that were added to the destination device by
 *	dev_uc_sync(). This function is intended to be called from the
 *	dev->stop function of layered software devices.
 */
void dev_uc_unsync(struct net_device *to, struct net_device *from)
{
	if (to->addr_len != from->addr_len)
		return;

	netif_addr_lock_bh(from);
	netif_addr_lock(to);
	__hw_addr_unsync(&to->uc, &from->uc, to->addr_len);
	__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	netif_addr_unlock_bh(from);
}
EXPORT_SYMBOL(dev_uc_unsync);

/**
 *	dev_uc_flush - Flush unicast addresses
 *	@dev: device
 *
 *	Flush unicast addresses.
 */
void dev_uc_flush(struct net_device *dev)
{
	netif_addr_lock_bh(dev);
	__hw_addr_flush(&dev->uc);
	netif_addr_unlock_bh(dev);
}
EXPORT_SYMBOL(dev_uc_flush);

/**
 *	dev_uc_flush - Init unicast address list
 *	@dev: device
 *
 *	Init unicast address list.
 */
void dev_uc_init(struct net_device *dev)
{
	__hw_addr_init(&dev->uc);
}
EXPORT_SYMBOL(dev_uc_init);

/*
 * Multicast list handling functions
 */

static int __dev_mc_add(struct net_device *dev, unsigned char *addr,
			bool global)
{
	int err;

	netif_addr_lock_bh(dev);
	err = __hw_addr_add_ex(&dev->mc, addr, dev->addr_len,
			       NETDEV_HW_ADDR_T_MULTICAST, global);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}
/**
 *	dev_mc_add - Add a multicast address
 *	@dev: device
 *	@addr: address to add
 *
 *	Add a multicast address to the device or increase
 *	the reference count if it already exists.
 */
int dev_mc_add(struct net_device *dev, unsigned char *addr)
{
	return __dev_mc_add(dev, addr, false);
}
EXPORT_SYMBOL(dev_mc_add);

/**
 *	dev_mc_add_global - Add a global multicast address
 *	@dev: device
 *	@addr: address to add
 *
 *	Add a global multicast address to the device.
 */
int dev_mc_add_global(struct net_device *dev, unsigned char *addr)
{
	return __dev_mc_add(dev, addr, true);
}
EXPORT_SYMBOL(dev_mc_add_global);

static int __dev_mc_del(struct net_device *dev, unsigned char *addr,
			bool global)
{
	int err;

	netif_addr_lock_bh(dev);
	err = __hw_addr_del_ex(&dev->mc, addr, dev->addr_len,
			       NETDEV_HW_ADDR_T_MULTICAST, global);
	if (!err)
		__dev_set_rx_mode(dev);
	netif_addr_unlock_bh(dev);
	return err;
}

/**
 *	dev_mc_del - Delete a multicast address.
 *	@dev: device
 *	@addr: address to delete
 *
 *	Release reference to a multicast address and remove it
 *	from the device if the reference count drops to zero.
 */
int dev_mc_del(struct net_device *dev, unsigned char *addr)
{
	return __dev_mc_del(dev, addr, false);
}
EXPORT_SYMBOL(dev_mc_del);

/**
 *	dev_mc_del_global - Delete a global multicast address.
 *	@dev: device
 *	@addr: address to delete
 *
 *	Release reference to a multicast address and remove it
 *	from the device if the reference count drops to zero.
 */
int dev_mc_del_global(struct net_device *dev, unsigned char *addr)
{
	return __dev_mc_del(dev, addr, true);
}
EXPORT_SYMBOL(dev_mc_del_global);

/**
 *	dev_mc_sync - Synchronize device's unicast list to another device
 *	@to: destination device
 *	@from: source device
 *
 *	Add newly added addresses to the destination device and release
 *	addresses that have no users left. The source device must be
 *	locked by netif_tx_lock_bh.
 *
 *	This function is intended to be called from the ndo_set_rx_mode
 *	function of layered software devices.
 */
int dev_mc_sync(struct net_device *to, struct net_device *from)
{
	int err = 0;

	if (to->addr_len != from->addr_len)
		return -EINVAL;

	netif_addr_lock_bh(to);
	err = __hw_addr_sync(&to->mc, &from->mc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock_bh(to);
	return err;
}
EXPORT_SYMBOL(dev_mc_sync);

/**
 *	dev_mc_unsync - Remove synchronized addresses from the destination device
 *	@to: destination device
 *	@from: source device
 *
 *	Remove all addresses that were added to the destination device by
 *	dev_mc_sync(). This function is intended to be called from the
 *	dev->stop function of layered software devices.
 */
void dev_mc_unsync(struct net_device *to, struct net_device *from)
{
	if (to->addr_len != from->addr_len)
		return;

	netif_addr_lock_bh(from);
	netif_addr_lock(to);
	__hw_addr_unsync(&to->mc, &from->mc, to->addr_len);
	__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	netif_addr_unlock_bh(from);
}
EXPORT_SYMBOL(dev_mc_unsync);

/**
 *	dev_mc_flush - Flush multicast addresses
 *	@dev: device
 *
 *	Flush multicast addresses.
 */
void dev_mc_flush(struct net_device *dev)
{
	netif_addr_lock_bh(dev);
	__hw_addr_flush(&dev->mc);
	netif_addr_unlock_bh(dev);
}
EXPORT_SYMBOL(dev_mc_flush);

/**
 *	dev_mc_flush - Init multicast address list
 *	@dev: device
 *
 *	Init multicast address list.
 */
void dev_mc_init(struct net_device *dev)
{
	__hw_addr_init(&dev->mc);
}
EXPORT_SYMBOL(dev_mc_init);

#ifdef CONFIG_PROC_FS
#include <linux/seq_file.h>

static int dev_mc_seq_show(struct seq_file *seq, void *v)
{
	struct netdev_hw_addr *ha;
	struct net_device *dev = v;

	if (v == SEQ_START_TOKEN)
		return 0;

	netif_addr_lock_bh(dev);
	netdev_for_each_mc_addr(ha, dev) {
		int i;

		seq_printf(seq, "%-4d %-15s %-5d %-5d ", dev->ifindex,
			   dev->name, ha->refcount, ha->global_use);

		for (i = 0; i < dev->addr_len; i++)
			seq_printf(seq, "%02x", ha->addr[i]);

		seq_putc(seq, '\n');
	}
	netif_addr_unlock_bh(dev);
	return 0;
}

static const struct seq_operations dev_mc_seq_ops = {
	.start = dev_seq_start,
	.next  = dev_seq_next,
	.stop  = dev_seq_stop,
	.show  = dev_mc_seq_show,
};

static int dev_mc_seq_open(struct inode *inode, struct file *file)
{
	return seq_open_net(inode, file, &dev_mc_seq_ops,
			    sizeof(struct seq_net_private));
}

static const struct file_operations dev_mc_seq_fops = {
	.owner	 = THIS_MODULE,
	.open    = dev_mc_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release_net,
};

#endif

static int __net_init dev_mc_net_init(struct net *net)
{
	if (!proc_net_fops_create(net, "dev_mcast", 0, &dev_mc_seq_fops))
		return -ENOMEM;
	return 0;
}

static void __net_exit dev_mc_net_exit(struct net *net)
{
	proc_net_remove(net, "dev_mcast");
}

static struct pernet_operations __net_initdata dev_mc_net_ops = {
	.init = dev_mc_net_init,
	.exit = dev_mc_net_exit,
};

void __init dev_mcast_init(void)
{
	register_pernet_subsys(&dev_mc_net_ops);
}