1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/core/dev_addr_lists.c - Functions for handling net device lists
4  * Copyright (c) 2010 Jiri Pirko <jpirko@redhat.com>
5  *
6  * This file contains functions for working with unicast, multicast and device
7  * addresses lists.
8  */
9 
10 #include <linux/netdevice.h>
11 #include <linux/rtnetlink.h>
12 #include <linux/export.h>
13 #include <linux/list.h>
14 
15 #include "dev.h"
16 
17 /*
18  * General list handling functions
19  */
20 
__hw_addr_insert(struct netdev_hw_addr_list * list,struct netdev_hw_addr * new,int addr_len)21 static int __hw_addr_insert(struct netdev_hw_addr_list *list,
22 			    struct netdev_hw_addr *new, int addr_len)
23 {
24 	struct rb_node **ins_point = &list->tree.rb_node, *parent = NULL;
25 	struct netdev_hw_addr *ha;
26 
27 	while (*ins_point) {
28 		int diff;
29 
30 		ha = rb_entry(*ins_point, struct netdev_hw_addr, node);
31 		diff = memcmp(new->addr, ha->addr, addr_len);
32 		if (diff == 0)
33 			diff = memcmp(&new->type, &ha->type, sizeof(new->type));
34 
35 		parent = *ins_point;
36 		if (diff < 0)
37 			ins_point = &parent->rb_left;
38 		else if (diff > 0)
39 			ins_point = &parent->rb_right;
40 		else
41 			return -EEXIST;
42 	}
43 
44 	rb_link_node_rcu(&new->node, parent, ins_point);
45 	rb_insert_color(&new->node, &list->tree);
46 
47 	return 0;
48 }
49 
50 static struct netdev_hw_addr*
__hw_addr_create(const unsigned char * addr,int addr_len,unsigned char addr_type,bool global,bool sync)51 __hw_addr_create(const unsigned char *addr, int addr_len,
52 		 unsigned char addr_type, bool global, bool sync)
53 {
54 	struct netdev_hw_addr *ha;
55 	int alloc_size;
56 
57 	alloc_size = sizeof(*ha);
58 	if (alloc_size < L1_CACHE_BYTES)
59 		alloc_size = L1_CACHE_BYTES;
60 	ha = kmalloc(alloc_size, GFP_ATOMIC);
61 	if (!ha)
62 		return NULL;
63 	memcpy(ha->addr, addr, addr_len);
64 	ha->type = addr_type;
65 	ha->refcount = 1;
66 	ha->global_use = global;
67 	ha->synced = sync ? 1 : 0;
68 	ha->sync_cnt = 0;
69 
70 	return ha;
71 }
72 
__hw_addr_add_ex(struct netdev_hw_addr_list * list,const unsigned char * addr,int addr_len,unsigned char addr_type,bool global,bool sync,int sync_count,bool exclusive)73 static int __hw_addr_add_ex(struct netdev_hw_addr_list *list,
74 			    const unsigned char *addr, int addr_len,
75 			    unsigned char addr_type, bool global, bool sync,
76 			    int sync_count, bool exclusive)
77 {
78 	struct rb_node **ins_point = &list->tree.rb_node, *parent = NULL;
79 	struct netdev_hw_addr *ha;
80 
81 	if (addr_len > MAX_ADDR_LEN)
82 		return -EINVAL;
83 
84 	while (*ins_point) {
85 		int diff;
86 
87 		ha = rb_entry(*ins_point, struct netdev_hw_addr, node);
88 		diff = memcmp(addr, ha->addr, addr_len);
89 		if (diff == 0)
90 			diff = memcmp(&addr_type, &ha->type, sizeof(addr_type));
91 
92 		parent = *ins_point;
93 		if (diff < 0) {
94 			ins_point = &parent->rb_left;
95 		} else if (diff > 0) {
96 			ins_point = &parent->rb_right;
97 		} else {
98 			if (exclusive)
99 				return -EEXIST;
100 			if (global) {
101 				/* check if addr is already used as global */
102 				if (ha->global_use)
103 					return 0;
104 				else
105 					ha->global_use = true;
106 			}
107 			if (sync) {
108 				if (ha->synced && sync_count)
109 					return -EEXIST;
110 				else
111 					ha->synced++;
112 			}
113 			ha->refcount++;
114 			return 0;
115 		}
116 	}
117 
118 	ha = __hw_addr_create(addr, addr_len, addr_type, global, sync);
119 	if (!ha)
120 		return -ENOMEM;
121 
122 	rb_link_node(&ha->node, parent, ins_point);
123 	rb_insert_color(&ha->node, &list->tree);
124 
125 	list_add_tail_rcu(&ha->list, &list->list);
126 	list->count++;
127 
128 	return 0;
129 }
130 
__hw_addr_add(struct netdev_hw_addr_list * list,const unsigned char * addr,int addr_len,unsigned char addr_type)131 static int __hw_addr_add(struct netdev_hw_addr_list *list,
132 			 const unsigned char *addr, int addr_len,
133 			 unsigned char addr_type)
134 {
135 	return __hw_addr_add_ex(list, addr, addr_len, addr_type, false, false,
136 				0, false);
137 }
138 
__hw_addr_del_entry(struct netdev_hw_addr_list * list,struct netdev_hw_addr * ha,bool global,bool sync)139 static int __hw_addr_del_entry(struct netdev_hw_addr_list *list,
140 			       struct netdev_hw_addr *ha, bool global,
141 			       bool sync)
142 {
143 	if (global && !ha->global_use)
144 		return -ENOENT;
145 
146 	if (sync && !ha->synced)
147 		return -ENOENT;
148 
149 	if (global)
150 		ha->global_use = false;
151 
152 	if (sync)
153 		ha->synced--;
154 
155 	if (--ha->refcount)
156 		return 0;
157 
158 	rb_erase(&ha->node, &list->tree);
159 
160 	list_del_rcu(&ha->list);
161 	kfree_rcu(ha, rcu_head);
162 	list->count--;
163 	return 0;
164 }
165 
__hw_addr_lookup(struct netdev_hw_addr_list * list,const unsigned char * addr,int addr_len,unsigned char addr_type)166 static struct netdev_hw_addr *__hw_addr_lookup(struct netdev_hw_addr_list *list,
167 					       const unsigned char *addr, int addr_len,
168 					       unsigned char addr_type)
169 {
170 	struct rb_node *node;
171 
172 	node = list->tree.rb_node;
173 
174 	while (node) {
175 		struct netdev_hw_addr *ha = rb_entry(node, struct netdev_hw_addr, node);
176 		int diff = memcmp(addr, ha->addr, addr_len);
177 
178 		if (diff == 0 && addr_type)
179 			diff = memcmp(&addr_type, &ha->type, sizeof(addr_type));
180 
181 		if (diff < 0)
182 			node = node->rb_left;
183 		else if (diff > 0)
184 			node = node->rb_right;
185 		else
186 			return ha;
187 	}
188 
189 	return NULL;
190 }
191 
__hw_addr_del_ex(struct netdev_hw_addr_list * list,const unsigned char * addr,int addr_len,unsigned char addr_type,bool global,bool sync)192 static int __hw_addr_del_ex(struct netdev_hw_addr_list *list,
193 			    const unsigned char *addr, int addr_len,
194 			    unsigned char addr_type, bool global, bool sync)
195 {
196 	struct netdev_hw_addr *ha = __hw_addr_lookup(list, addr, addr_len, addr_type);
197 
198 	if (!ha)
199 		return -ENOENT;
200 	return __hw_addr_del_entry(list, ha, global, sync);
201 }
202 
__hw_addr_del(struct netdev_hw_addr_list * list,const unsigned char * addr,int addr_len,unsigned char addr_type)203 static int __hw_addr_del(struct netdev_hw_addr_list *list,
204 			 const unsigned char *addr, int addr_len,
205 			 unsigned char addr_type)
206 {
207 	return __hw_addr_del_ex(list, addr, addr_len, addr_type, false, false);
208 }
209 
__hw_addr_sync_one(struct netdev_hw_addr_list * to_list,struct netdev_hw_addr * ha,int addr_len)210 static int __hw_addr_sync_one(struct netdev_hw_addr_list *to_list,
211 			       struct netdev_hw_addr *ha,
212 			       int addr_len)
213 {
214 	int err;
215 
216 	err = __hw_addr_add_ex(to_list, ha->addr, addr_len, ha->type,
217 			       false, true, ha->sync_cnt, false);
218 	if (err && err != -EEXIST)
219 		return err;
220 
221 	if (!err) {
222 		ha->sync_cnt++;
223 		ha->refcount++;
224 	}
225 
226 	return 0;
227 }
228 
__hw_addr_unsync_one(struct netdev_hw_addr_list * to_list,struct netdev_hw_addr_list * from_list,struct netdev_hw_addr * ha,int addr_len)229 static void __hw_addr_unsync_one(struct netdev_hw_addr_list *to_list,
230 				 struct netdev_hw_addr_list *from_list,
231 				 struct netdev_hw_addr *ha,
232 				 int addr_len)
233 {
234 	int err;
235 
236 	err = __hw_addr_del_ex(to_list, ha->addr, addr_len, ha->type,
237 			       false, true);
238 	if (err)
239 		return;
240 	ha->sync_cnt--;
241 	/* address on from list is not marked synced */
242 	__hw_addr_del_entry(from_list, ha, false, false);
243 }
244 
__hw_addr_sync_multiple(struct netdev_hw_addr_list * to_list,struct netdev_hw_addr_list * from_list,int addr_len)245 static int __hw_addr_sync_multiple(struct netdev_hw_addr_list *to_list,
246 				   struct netdev_hw_addr_list *from_list,
247 				   int addr_len)
248 {
249 	int err = 0;
250 	struct netdev_hw_addr *ha, *tmp;
251 
252 	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
253 		if (ha->sync_cnt == ha->refcount) {
254 			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
255 		} else {
256 			err = __hw_addr_sync_one(to_list, ha, addr_len);
257 			if (err)
258 				break;
259 		}
260 	}
261 	return err;
262 }
263 
264 /* This function only works where there is a strict 1-1 relationship
265  * between source and destionation of they synch. If you ever need to
266  * sync addresses to more then 1 destination, you need to use
267  * __hw_addr_sync_multiple().
268  */
__hw_addr_sync(struct netdev_hw_addr_list * to_list,struct netdev_hw_addr_list * from_list,int addr_len)269 int __hw_addr_sync(struct netdev_hw_addr_list *to_list,
270 		   struct netdev_hw_addr_list *from_list,
271 		   int addr_len)
272 {
273 	int err = 0;
274 	struct netdev_hw_addr *ha, *tmp;
275 
276 	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
277 		if (!ha->sync_cnt) {
278 			err = __hw_addr_sync_one(to_list, ha, addr_len);
279 			if (err)
280 				break;
281 		} else if (ha->refcount == 1)
282 			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
283 	}
284 	return err;
285 }
286 EXPORT_SYMBOL(__hw_addr_sync);
287 
__hw_addr_unsync(struct netdev_hw_addr_list * to_list,struct netdev_hw_addr_list * from_list,int addr_len)288 void __hw_addr_unsync(struct netdev_hw_addr_list *to_list,
289 		      struct netdev_hw_addr_list *from_list,
290 		      int addr_len)
291 {
292 	struct netdev_hw_addr *ha, *tmp;
293 
294 	list_for_each_entry_safe(ha, tmp, &from_list->list, list) {
295 		if (ha->sync_cnt)
296 			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
297 	}
298 }
299 EXPORT_SYMBOL(__hw_addr_unsync);
300 
301 /**
302  *  __hw_addr_sync_dev - Synchonize device's multicast list
303  *  @list: address list to syncronize
304  *  @dev:  device to sync
305  *  @sync: function to call if address should be added
306  *  @unsync: function to call if address should be removed
307  *
308  *  This function is intended to be called from the ndo_set_rx_mode
309  *  function of devices that require explicit address add/remove
310  *  notifications.  The unsync function may be NULL in which case
311  *  the addresses requiring removal will simply be removed without
312  *  any notification to the device.
313  **/
__hw_addr_sync_dev(struct netdev_hw_addr_list * list,struct net_device * dev,int (* sync)(struct net_device *,const unsigned char *),int (* unsync)(struct net_device *,const unsigned char *))314 int __hw_addr_sync_dev(struct netdev_hw_addr_list *list,
315 		       struct net_device *dev,
316 		       int (*sync)(struct net_device *, const unsigned char *),
317 		       int (*unsync)(struct net_device *,
318 				     const unsigned char *))
319 {
320 	struct netdev_hw_addr *ha, *tmp;
321 	int err;
322 
323 	/* first go through and flush out any stale entries */
324 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
325 		if (!ha->sync_cnt || ha->refcount != 1)
326 			continue;
327 
328 		/* if unsync is defined and fails defer unsyncing address */
329 		if (unsync && unsync(dev, ha->addr))
330 			continue;
331 
332 		ha->sync_cnt--;
333 		__hw_addr_del_entry(list, ha, false, false);
334 	}
335 
336 	/* go through and sync new entries to the list */
337 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
338 		if (ha->sync_cnt)
339 			continue;
340 
341 		err = sync(dev, ha->addr);
342 		if (err)
343 			return err;
344 
345 		ha->sync_cnt++;
346 		ha->refcount++;
347 	}
348 
349 	return 0;
350 }
351 EXPORT_SYMBOL(__hw_addr_sync_dev);
352 
353 /**
354  *  __hw_addr_ref_sync_dev - Synchronize device's multicast address list taking
355  *  into account references
356  *  @list: address list to synchronize
357  *  @dev:  device to sync
358  *  @sync: function to call if address or reference on it should be added
359  *  @unsync: function to call if address or some reference on it should removed
360  *
361  *  This function is intended to be called from the ndo_set_rx_mode
362  *  function of devices that require explicit address or references on it
363  *  add/remove notifications. The unsync function may be NULL in which case
364  *  the addresses or references on it requiring removal will simply be
365  *  removed without any notification to the device. That is responsibility of
366  *  the driver to identify and distribute address or references on it between
367  *  internal address tables.
368  **/
__hw_addr_ref_sync_dev(struct netdev_hw_addr_list * list,struct net_device * dev,int (* sync)(struct net_device *,const unsigned char *,int),int (* unsync)(struct net_device *,const unsigned char *,int))369 int __hw_addr_ref_sync_dev(struct netdev_hw_addr_list *list,
370 			   struct net_device *dev,
371 			   int (*sync)(struct net_device *,
372 				       const unsigned char *, int),
373 			   int (*unsync)(struct net_device *,
374 					 const unsigned char *, int))
375 {
376 	struct netdev_hw_addr *ha, *tmp;
377 	int err, ref_cnt;
378 
379 	/* first go through and flush out any unsynced/stale entries */
380 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
381 		/* sync if address is not used */
382 		if ((ha->sync_cnt << 1) <= ha->refcount)
383 			continue;
384 
385 		/* if fails defer unsyncing address */
386 		ref_cnt = ha->refcount - ha->sync_cnt;
387 		if (unsync && unsync(dev, ha->addr, ref_cnt))
388 			continue;
389 
390 		ha->refcount = (ref_cnt << 1) + 1;
391 		ha->sync_cnt = ref_cnt;
392 		__hw_addr_del_entry(list, ha, false, false);
393 	}
394 
395 	/* go through and sync updated/new entries to the list */
396 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
397 		/* sync if address added or reused */
398 		if ((ha->sync_cnt << 1) >= ha->refcount)
399 			continue;
400 
401 		ref_cnt = ha->refcount - ha->sync_cnt;
402 		err = sync(dev, ha->addr, ref_cnt);
403 		if (err)
404 			return err;
405 
406 		ha->refcount = ref_cnt << 1;
407 		ha->sync_cnt = ref_cnt;
408 	}
409 
410 	return 0;
411 }
412 EXPORT_SYMBOL(__hw_addr_ref_sync_dev);
413 
414 /**
415  *  __hw_addr_ref_unsync_dev - Remove synchronized addresses and references on
416  *  it from device
417  *  @list: address list to remove synchronized addresses (references on it) from
418  *  @dev:  device to sync
419  *  @unsync: function to call if address and references on it should be removed
420  *
421  *  Remove all addresses that were added to the device by
422  *  __hw_addr_ref_sync_dev(). This function is intended to be called from the
423  *  ndo_stop or ndo_open functions on devices that require explicit address (or
424  *  references on it) add/remove notifications. If the unsync function pointer
425  *  is NULL then this function can be used to just reset the sync_cnt for the
426  *  addresses in the list.
427  **/
__hw_addr_ref_unsync_dev(struct netdev_hw_addr_list * list,struct net_device * dev,int (* unsync)(struct net_device *,const unsigned char *,int))428 void __hw_addr_ref_unsync_dev(struct netdev_hw_addr_list *list,
429 			      struct net_device *dev,
430 			      int (*unsync)(struct net_device *,
431 					    const unsigned char *, int))
432 {
433 	struct netdev_hw_addr *ha, *tmp;
434 
435 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
436 		if (!ha->sync_cnt)
437 			continue;
438 
439 		/* if fails defer unsyncing address */
440 		if (unsync && unsync(dev, ha->addr, ha->sync_cnt))
441 			continue;
442 
443 		ha->refcount -= ha->sync_cnt - 1;
444 		ha->sync_cnt = 0;
445 		__hw_addr_del_entry(list, ha, false, false);
446 	}
447 }
448 EXPORT_SYMBOL(__hw_addr_ref_unsync_dev);
449 
450 /**
451  *  __hw_addr_unsync_dev - Remove synchronized addresses from device
452  *  @list: address list to remove synchronized addresses from
453  *  @dev:  device to sync
454  *  @unsync: function to call if address should be removed
455  *
456  *  Remove all addresses that were added to the device by __hw_addr_sync_dev().
457  *  This function is intended to be called from the ndo_stop or ndo_open
458  *  functions on devices that require explicit address add/remove
459  *  notifications.  If the unsync function pointer is NULL then this function
460  *  can be used to just reset the sync_cnt for the addresses in the list.
461  **/
__hw_addr_unsync_dev(struct netdev_hw_addr_list * list,struct net_device * dev,int (* unsync)(struct net_device *,const unsigned char *))462 void __hw_addr_unsync_dev(struct netdev_hw_addr_list *list,
463 			  struct net_device *dev,
464 			  int (*unsync)(struct net_device *,
465 					const unsigned char *))
466 {
467 	struct netdev_hw_addr *ha, *tmp;
468 
469 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
470 		if (!ha->sync_cnt)
471 			continue;
472 
473 		/* if unsync is defined and fails defer unsyncing address */
474 		if (unsync && unsync(dev, ha->addr))
475 			continue;
476 
477 		ha->sync_cnt--;
478 		__hw_addr_del_entry(list, ha, false, false);
479 	}
480 }
481 EXPORT_SYMBOL(__hw_addr_unsync_dev);
482 
__hw_addr_flush(struct netdev_hw_addr_list * list)483 static void __hw_addr_flush(struct netdev_hw_addr_list *list)
484 {
485 	struct netdev_hw_addr *ha, *tmp;
486 
487 	list->tree = RB_ROOT;
488 	list_for_each_entry_safe(ha, tmp, &list->list, list) {
489 		list_del_rcu(&ha->list);
490 		kfree_rcu(ha, rcu_head);
491 	}
492 	list->count = 0;
493 }
494 
__hw_addr_init(struct netdev_hw_addr_list * list)495 void __hw_addr_init(struct netdev_hw_addr_list *list)
496 {
497 	INIT_LIST_HEAD(&list->list);
498 	list->count = 0;
499 	list->tree = RB_ROOT;
500 }
501 EXPORT_SYMBOL(__hw_addr_init);
502 
503 /*
504  * Device addresses handling functions
505  */
506 
507 /* Check that netdev->dev_addr is not written to directly as this would
508  * break the rbtree layout. All changes should go thru dev_addr_set() and co.
509  * Remove this check in mid-2024.
510  */
dev_addr_check(struct net_device * dev)511 void dev_addr_check(struct net_device *dev)
512 {
513 	if (!memcmp(dev->dev_addr, dev->dev_addr_shadow, MAX_ADDR_LEN))
514 		return;
515 
516 	netdev_warn(dev, "Current addr:  %*ph\n", MAX_ADDR_LEN, dev->dev_addr);
517 	netdev_warn(dev, "Expected addr: %*ph\n",
518 		    MAX_ADDR_LEN, dev->dev_addr_shadow);
519 	netdev_WARN(dev, "Incorrect netdev->dev_addr\n");
520 }
521 
522 /**
523  *	dev_addr_flush - Flush device address list
524  *	@dev: device
525  *
526  *	Flush device address list and reset ->dev_addr.
527  *
528  *	The caller must hold the rtnl_mutex.
529  */
dev_addr_flush(struct net_device * dev)530 void dev_addr_flush(struct net_device *dev)
531 {
532 	/* rtnl_mutex must be held here */
533 	dev_addr_check(dev);
534 
535 	__hw_addr_flush(&dev->dev_addrs);
536 	dev->dev_addr = NULL;
537 }
538 
539 /**
540  *	dev_addr_init - Init device address list
541  *	@dev: device
542  *
543  *	Init device address list and create the first element,
544  *	used by ->dev_addr.
545  *
546  *	The caller must hold the rtnl_mutex.
547  */
dev_addr_init(struct net_device * dev)548 int dev_addr_init(struct net_device *dev)
549 {
550 	unsigned char addr[MAX_ADDR_LEN];
551 	struct netdev_hw_addr *ha;
552 	int err;
553 
554 	/* rtnl_mutex must be held here */
555 
556 	__hw_addr_init(&dev->dev_addrs);
557 	memset(addr, 0, sizeof(addr));
558 	err = __hw_addr_add(&dev->dev_addrs, addr, sizeof(addr),
559 			    NETDEV_HW_ADDR_T_LAN);
560 	if (!err) {
561 		/*
562 		 * Get the first (previously created) address from the list
563 		 * and set dev_addr pointer to this location.
564 		 */
565 		ha = list_first_entry(&dev->dev_addrs.list,
566 				      struct netdev_hw_addr, list);
567 		dev->dev_addr = ha->addr;
568 	}
569 	return err;
570 }
571 
dev_addr_mod(struct net_device * dev,unsigned int offset,const void * addr,size_t len)572 void dev_addr_mod(struct net_device *dev, unsigned int offset,
573 		  const void *addr, size_t len)
574 {
575 	struct netdev_hw_addr *ha;
576 
577 	dev_addr_check(dev);
578 
579 	ha = container_of(dev->dev_addr, struct netdev_hw_addr, addr[0]);
580 	rb_erase(&ha->node, &dev->dev_addrs.tree);
581 	memcpy(&ha->addr[offset], addr, len);
582 	memcpy(&dev->dev_addr_shadow[offset], addr, len);
583 	WARN_ON(__hw_addr_insert(&dev->dev_addrs, ha, dev->addr_len));
584 }
585 EXPORT_SYMBOL(dev_addr_mod);
586 
587 /**
588  *	dev_addr_add - Add a device address
589  *	@dev: device
590  *	@addr: address to add
591  *	@addr_type: address type
592  *
593  *	Add a device address to the device or increase the reference count if
594  *	it already exists.
595  *
596  *	The caller must hold the rtnl_mutex.
597  */
dev_addr_add(struct net_device * dev,const unsigned char * addr,unsigned char addr_type)598 int dev_addr_add(struct net_device *dev, const unsigned char *addr,
599 		 unsigned char addr_type)
600 {
601 	int err;
602 
603 	ASSERT_RTNL();
604 
605 	err = dev_pre_changeaddr_notify(dev, addr, NULL);
606 	if (err)
607 		return err;
608 	err = __hw_addr_add(&dev->dev_addrs, addr, dev->addr_len, addr_type);
609 	if (!err)
610 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
611 	return err;
612 }
613 EXPORT_SYMBOL(dev_addr_add);
614 
615 /**
616  *	dev_addr_del - Release a device address.
617  *	@dev: device
618  *	@addr: address to delete
619  *	@addr_type: address type
620  *
621  *	Release reference to a device address and remove it from the device
622  *	if the reference count drops to zero.
623  *
624  *	The caller must hold the rtnl_mutex.
625  */
dev_addr_del(struct net_device * dev,const unsigned char * addr,unsigned char addr_type)626 int dev_addr_del(struct net_device *dev, const unsigned char *addr,
627 		 unsigned char addr_type)
628 {
629 	int err;
630 	struct netdev_hw_addr *ha;
631 
632 	ASSERT_RTNL();
633 
634 	/*
635 	 * We can not remove the first address from the list because
636 	 * dev->dev_addr points to that.
637 	 */
638 	ha = list_first_entry(&dev->dev_addrs.list,
639 			      struct netdev_hw_addr, list);
640 	if (!memcmp(ha->addr, addr, dev->addr_len) &&
641 	    ha->type == addr_type && ha->refcount == 1)
642 		return -ENOENT;
643 
644 	err = __hw_addr_del(&dev->dev_addrs, addr, dev->addr_len,
645 			    addr_type);
646 	if (!err)
647 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
648 	return err;
649 }
650 EXPORT_SYMBOL(dev_addr_del);
651 
652 /*
653  * Unicast list handling functions
654  */
655 
656 /**
657  *	dev_uc_add_excl - Add a global secondary unicast address
658  *	@dev: device
659  *	@addr: address to add
660  */
dev_uc_add_excl(struct net_device * dev,const unsigned char * addr)661 int dev_uc_add_excl(struct net_device *dev, const unsigned char *addr)
662 {
663 	int err;
664 
665 	netif_addr_lock_bh(dev);
666 	err = __hw_addr_add_ex(&dev->uc, addr, dev->addr_len,
667 			       NETDEV_HW_ADDR_T_UNICAST, true, false,
668 			       0, true);
669 	if (!err)
670 		__dev_set_rx_mode(dev);
671 	netif_addr_unlock_bh(dev);
672 	return err;
673 }
674 EXPORT_SYMBOL(dev_uc_add_excl);
675 
676 /**
677  *	dev_uc_add - Add a secondary unicast address
678  *	@dev: device
679  *	@addr: address to add
680  *
681  *	Add a secondary unicast address to the device or increase
682  *	the reference count if it already exists.
683  */
dev_uc_add(struct net_device * dev,const unsigned char * addr)684 int dev_uc_add(struct net_device *dev, const unsigned char *addr)
685 {
686 	int err;
687 
688 	netif_addr_lock_bh(dev);
689 	err = __hw_addr_add(&dev->uc, addr, dev->addr_len,
690 			    NETDEV_HW_ADDR_T_UNICAST);
691 	if (!err)
692 		__dev_set_rx_mode(dev);
693 	netif_addr_unlock_bh(dev);
694 	return err;
695 }
696 EXPORT_SYMBOL(dev_uc_add);
697 
698 /**
699  *	dev_uc_del - Release secondary unicast address.
700  *	@dev: device
701  *	@addr: address to delete
702  *
703  *	Release reference to a secondary unicast address and remove it
704  *	from the device if the reference count drops to zero.
705  */
dev_uc_del(struct net_device * dev,const unsigned char * addr)706 int dev_uc_del(struct net_device *dev, const unsigned char *addr)
707 {
708 	int err;
709 
710 	netif_addr_lock_bh(dev);
711 	err = __hw_addr_del(&dev->uc, addr, dev->addr_len,
712 			    NETDEV_HW_ADDR_T_UNICAST);
713 	if (!err)
714 		__dev_set_rx_mode(dev);
715 	netif_addr_unlock_bh(dev);
716 	return err;
717 }
718 EXPORT_SYMBOL(dev_uc_del);
719 
720 /**
721  *	dev_uc_sync - Synchronize device's unicast list to another device
722  *	@to: destination device
723  *	@from: source device
724  *
725  *	Add newly added addresses to the destination device and release
726  *	addresses that have no users left. The source device must be
727  *	locked by netif_addr_lock_bh.
728  *
729  *	This function is intended to be called from the dev->set_rx_mode
730  *	function of layered software devices.  This function assumes that
731  *	addresses will only ever be synced to the @to devices and no other.
732  */
dev_uc_sync(struct net_device * to,struct net_device * from)733 int dev_uc_sync(struct net_device *to, struct net_device *from)
734 {
735 	int err = 0;
736 
737 	if (to->addr_len != from->addr_len)
738 		return -EINVAL;
739 
740 	netif_addr_lock(to);
741 	err = __hw_addr_sync(&to->uc, &from->uc, to->addr_len);
742 	if (!err)
743 		__dev_set_rx_mode(to);
744 	netif_addr_unlock(to);
745 	return err;
746 }
747 EXPORT_SYMBOL(dev_uc_sync);
748 
749 /**
750  *	dev_uc_sync_multiple - Synchronize device's unicast list to another
751  *	device, but allow for multiple calls to sync to multiple devices.
752  *	@to: destination device
753  *	@from: source device
754  *
755  *	Add newly added addresses to the destination device and release
756  *	addresses that have been deleted from the source. The source device
757  *	must be locked by netif_addr_lock_bh.
758  *
759  *	This function is intended to be called from the dev->set_rx_mode
760  *	function of layered software devices.  It allows for a single source
761  *	device to be synced to multiple destination devices.
762  */
dev_uc_sync_multiple(struct net_device * to,struct net_device * from)763 int dev_uc_sync_multiple(struct net_device *to, struct net_device *from)
764 {
765 	int err = 0;
766 
767 	if (to->addr_len != from->addr_len)
768 		return -EINVAL;
769 
770 	netif_addr_lock(to);
771 	err = __hw_addr_sync_multiple(&to->uc, &from->uc, to->addr_len);
772 	if (!err)
773 		__dev_set_rx_mode(to);
774 	netif_addr_unlock(to);
775 	return err;
776 }
777 EXPORT_SYMBOL(dev_uc_sync_multiple);
778 
779 /**
780  *	dev_uc_unsync - Remove synchronized addresses from the destination device
781  *	@to: destination device
782  *	@from: source device
783  *
784  *	Remove all addresses that were added to the destination device by
785  *	dev_uc_sync(). This function is intended to be called from the
786  *	dev->stop function of layered software devices.
787  */
dev_uc_unsync(struct net_device * to,struct net_device * from)788 void dev_uc_unsync(struct net_device *to, struct net_device *from)
789 {
790 	if (to->addr_len != from->addr_len)
791 		return;
792 
793 	/* netif_addr_lock_bh() uses lockdep subclass 0, this is okay for two
794 	 * reasons:
795 	 * 1) This is always called without any addr_list_lock, so as the
796 	 *    outermost one here, it must be 0.
797 	 * 2) This is called by some callers after unlinking the upper device,
798 	 *    so the dev->lower_level becomes 1 again.
799 	 * Therefore, the subclass for 'from' is 0, for 'to' is either 1 or
800 	 * larger.
801 	 */
802 	netif_addr_lock_bh(from);
803 	netif_addr_lock(to);
804 	__hw_addr_unsync(&to->uc, &from->uc, to->addr_len);
805 	__dev_set_rx_mode(to);
806 	netif_addr_unlock(to);
807 	netif_addr_unlock_bh(from);
808 }
809 EXPORT_SYMBOL(dev_uc_unsync);
810 
811 /**
812  *	dev_uc_flush - Flush unicast addresses
813  *	@dev: device
814  *
815  *	Flush unicast addresses.
816  */
dev_uc_flush(struct net_device * dev)817 void dev_uc_flush(struct net_device *dev)
818 {
819 	netif_addr_lock_bh(dev);
820 	__hw_addr_flush(&dev->uc);
821 	netif_addr_unlock_bh(dev);
822 }
823 EXPORT_SYMBOL(dev_uc_flush);
824 
825 /**
826  *	dev_uc_init - Init unicast address list
827  *	@dev: device
828  *
829  *	Init unicast address list.
830  */
dev_uc_init(struct net_device * dev)831 void dev_uc_init(struct net_device *dev)
832 {
833 	__hw_addr_init(&dev->uc);
834 }
835 EXPORT_SYMBOL(dev_uc_init);
836 
837 /*
838  * Multicast list handling functions
839  */
840 
841 /**
842  *	dev_mc_add_excl - Add a global secondary multicast address
843  *	@dev: device
844  *	@addr: address to add
845  */
dev_mc_add_excl(struct net_device * dev,const unsigned char * addr)846 int dev_mc_add_excl(struct net_device *dev, const unsigned char *addr)
847 {
848 	int err;
849 
850 	netif_addr_lock_bh(dev);
851 	err = __hw_addr_add_ex(&dev->mc, addr, dev->addr_len,
852 			       NETDEV_HW_ADDR_T_MULTICAST, true, false,
853 			       0, true);
854 	if (!err)
855 		__dev_set_rx_mode(dev);
856 	netif_addr_unlock_bh(dev);
857 	return err;
858 }
859 EXPORT_SYMBOL(dev_mc_add_excl);
860 
__dev_mc_add(struct net_device * dev,const unsigned char * addr,bool global)861 static int __dev_mc_add(struct net_device *dev, const unsigned char *addr,
862 			bool global)
863 {
864 	int err;
865 
866 	netif_addr_lock_bh(dev);
867 	err = __hw_addr_add_ex(&dev->mc, addr, dev->addr_len,
868 			       NETDEV_HW_ADDR_T_MULTICAST, global, false,
869 			       0, false);
870 	if (!err)
871 		__dev_set_rx_mode(dev);
872 	netif_addr_unlock_bh(dev);
873 	return err;
874 }
875 /**
876  *	dev_mc_add - Add a multicast address
877  *	@dev: device
878  *	@addr: address to add
879  *
880  *	Add a multicast address to the device or increase
881  *	the reference count if it already exists.
882  */
dev_mc_add(struct net_device * dev,const unsigned char * addr)883 int dev_mc_add(struct net_device *dev, const unsigned char *addr)
884 {
885 	return __dev_mc_add(dev, addr, false);
886 }
887 EXPORT_SYMBOL(dev_mc_add);
888 
889 /**
890  *	dev_mc_add_global - Add a global multicast address
891  *	@dev: device
892  *	@addr: address to add
893  *
894  *	Add a global multicast address to the device.
895  */
dev_mc_add_global(struct net_device * dev,const unsigned char * addr)896 int dev_mc_add_global(struct net_device *dev, const unsigned char *addr)
897 {
898 	return __dev_mc_add(dev, addr, true);
899 }
900 EXPORT_SYMBOL(dev_mc_add_global);
901 
__dev_mc_del(struct net_device * dev,const unsigned char * addr,bool global)902 static int __dev_mc_del(struct net_device *dev, const unsigned char *addr,
903 			bool global)
904 {
905 	int err;
906 
907 	netif_addr_lock_bh(dev);
908 	err = __hw_addr_del_ex(&dev->mc, addr, dev->addr_len,
909 			       NETDEV_HW_ADDR_T_MULTICAST, global, false);
910 	if (!err)
911 		__dev_set_rx_mode(dev);
912 	netif_addr_unlock_bh(dev);
913 	return err;
914 }
915 
916 /**
917  *	dev_mc_del - Delete a multicast address.
918  *	@dev: device
919  *	@addr: address to delete
920  *
921  *	Release reference to a multicast address and remove it
922  *	from the device if the reference count drops to zero.
923  */
dev_mc_del(struct net_device * dev,const unsigned char * addr)924 int dev_mc_del(struct net_device *dev, const unsigned char *addr)
925 {
926 	return __dev_mc_del(dev, addr, false);
927 }
928 EXPORT_SYMBOL(dev_mc_del);
929 
930 /**
931  *	dev_mc_del_global - Delete a global multicast address.
932  *	@dev: device
933  *	@addr: address to delete
934  *
935  *	Release reference to a multicast address and remove it
936  *	from the device if the reference count drops to zero.
937  */
dev_mc_del_global(struct net_device * dev,const unsigned char * addr)938 int dev_mc_del_global(struct net_device *dev, const unsigned char *addr)
939 {
940 	return __dev_mc_del(dev, addr, true);
941 }
942 EXPORT_SYMBOL(dev_mc_del_global);
943 
944 /**
945  *	dev_mc_sync - Synchronize device's multicast list to another device
946  *	@to: destination device
947  *	@from: source device
948  *
949  *	Add newly added addresses to the destination device and release
950  *	addresses that have no users left. The source device must be
951  *	locked by netif_addr_lock_bh.
952  *
953  *	This function is intended to be called from the ndo_set_rx_mode
954  *	function of layered software devices.
955  */
dev_mc_sync(struct net_device * to,struct net_device * from)956 int dev_mc_sync(struct net_device *to, struct net_device *from)
957 {
958 	int err = 0;
959 
960 	if (to->addr_len != from->addr_len)
961 		return -EINVAL;
962 
963 	netif_addr_lock(to);
964 	err = __hw_addr_sync(&to->mc, &from->mc, to->addr_len);
965 	if (!err)
966 		__dev_set_rx_mode(to);
967 	netif_addr_unlock(to);
968 	return err;
969 }
970 EXPORT_SYMBOL(dev_mc_sync);
971 
972 /**
973  *	dev_mc_sync_multiple - Synchronize device's multicast list to another
974  *	device, but allow for multiple calls to sync to multiple devices.
975  *	@to: destination device
976  *	@from: source device
977  *
978  *	Add newly added addresses to the destination device and release
979  *	addresses that have no users left. The source device must be
980  *	locked by netif_addr_lock_bh.
981  *
982  *	This function is intended to be called from the ndo_set_rx_mode
983  *	function of layered software devices.  It allows for a single
984  *	source device to be synced to multiple destination devices.
985  */
dev_mc_sync_multiple(struct net_device * to,struct net_device * from)986 int dev_mc_sync_multiple(struct net_device *to, struct net_device *from)
987 {
988 	int err = 0;
989 
990 	if (to->addr_len != from->addr_len)
991 		return -EINVAL;
992 
993 	netif_addr_lock(to);
994 	err = __hw_addr_sync_multiple(&to->mc, &from->mc, to->addr_len);
995 	if (!err)
996 		__dev_set_rx_mode(to);
997 	netif_addr_unlock(to);
998 	return err;
999 }
1000 EXPORT_SYMBOL(dev_mc_sync_multiple);
1001 
1002 /**
1003  *	dev_mc_unsync - Remove synchronized addresses from the destination device
1004  *	@to: destination device
1005  *	@from: source device
1006  *
1007  *	Remove all addresses that were added to the destination device by
1008  *	dev_mc_sync(). This function is intended to be called from the
1009  *	dev->stop function of layered software devices.
1010  */
dev_mc_unsync(struct net_device * to,struct net_device * from)1011 void dev_mc_unsync(struct net_device *to, struct net_device *from)
1012 {
1013 	if (to->addr_len != from->addr_len)
1014 		return;
1015 
1016 	/* See the above comments inside dev_uc_unsync(). */
1017 	netif_addr_lock_bh(from);
1018 	netif_addr_lock(to);
1019 	__hw_addr_unsync(&to->mc, &from->mc, to->addr_len);
1020 	__dev_set_rx_mode(to);
1021 	netif_addr_unlock(to);
1022 	netif_addr_unlock_bh(from);
1023 }
1024 EXPORT_SYMBOL(dev_mc_unsync);
1025 
1026 /**
1027  *	dev_mc_flush - Flush multicast addresses
1028  *	@dev: device
1029  *
1030  *	Flush multicast addresses.
1031  */
dev_mc_flush(struct net_device * dev)1032 void dev_mc_flush(struct net_device *dev)
1033 {
1034 	netif_addr_lock_bh(dev);
1035 	__hw_addr_flush(&dev->mc);
1036 	netif_addr_unlock_bh(dev);
1037 }
1038 EXPORT_SYMBOL(dev_mc_flush);
1039 
1040 /**
1041  *	dev_mc_init - Init multicast address list
1042  *	@dev: device
1043  *
1044  *	Init multicast address list.
1045  */
dev_mc_init(struct net_device * dev)1046 void dev_mc_init(struct net_device *dev)
1047 {
1048 	__hw_addr_init(&dev->mc);
1049 }
1050 EXPORT_SYMBOL(dev_mc_init);
1051