dev_addr_lists.c 20.8 KB
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851
/*
 * 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>

/*
 * General list handling functions
 */

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

	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 = sync ? 1 : 0;
	ha->sync_cnt = 0;
	list_add_tail_rcu(&ha->list, &list->list);
	list->count++;

	return 0;
}

static int __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)
{
	struct netdev_hw_addr *ha;

	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;
			}
			if (sync) {
				if (ha->synced && sync_count)
					return -EEXIST;
				else
					ha->synced++;
			}
			ha->refcount++;
			return 0;
		}
	}

	return __hw_addr_create_ex(list, addr, addr_len, addr_type, global,
				   sync);
}

static int __hw_addr_add(struct netdev_hw_addr_list *list,
			 const unsigned char *addr, int addr_len,
			 unsigned char addr_type)
{
	return __hw_addr_add_ex(list, addr, addr_len, addr_type, false, false,
				0);
}

static int __hw_addr_del_entry(struct netdev_hw_addr_list *list,
			       struct netdev_hw_addr *ha, bool global,
			       bool sync)
{
	if (global && !ha->global_use)
		return -ENOENT;

	if (sync && !ha->synced)
		return -ENOENT;

	if (global)
		ha->global_use = false;

	if (sync)
		ha->synced--;

	if (--ha->refcount)
		return 0;
	list_del_rcu(&ha->list);
	kfree_rcu(ha, rcu_head);
	list->count--;
	return 0;
}

static int __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)
{
	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))
			return __hw_addr_del_entry(list, ha, global, sync);
	}
	return -ENOENT;
}

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

static int __hw_addr_sync_one(struct netdev_hw_addr_list *to_list,
			       struct netdev_hw_addr *ha,
			       int addr_len)
{
	int err;

	err = __hw_addr_add_ex(to_list, ha->addr, addr_len, ha->type,
			       false, true, ha->sync_cnt);
	if (err && err != -EEXIST)
		return err;

	if (!err) {
		ha->sync_cnt++;
		ha->refcount++;
	}

	return 0;
}

static void __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)
{
	int err;

	err = __hw_addr_del_ex(to_list, ha->addr, addr_len, ha->type,
			       false, true);
	if (err)
		return;
	ha->sync_cnt--;
	/* address on from list is not marked synced */
	__hw_addr_del_entry(from_list, ha, false, false);
}

static int __hw_addr_sync_multiple(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->sync_cnt == ha->refcount) {
			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
		} else {
			err = __hw_addr_sync_one(to_list, ha, addr_len);
			if (err)
				break;
		}
	}
	return err;
}

/* This function only works where there is a strict 1-1 relationship
 * between source and destionation of they synch. If you ever need to
 * sync addresses to more then 1 destination, you need to use
 * __hw_addr_sync_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->sync_cnt) {
			err = __hw_addr_sync_one(to_list, ha, addr_len);
			if (err)
				break;
		} else if (ha->refcount == 1)
			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
	}
	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->sync_cnt)
			__hw_addr_unsync_one(to_list, from_list, ha, addr_len);
	}
}
EXPORT_SYMBOL(__hw_addr_unsync);

/**
 *  __hw_addr_sync_dev - Synchonize device's multicast list
 *  @list: address list to syncronize
 *  @dev:  device to sync
 *  @sync: function to call if address should be added
 *  @unsync: function to call if address should be removed
 *
 *  This funciton is intended to be called from the ndo_set_rx_mode
 *  function of devices that require explicit address add/remove
 *  notifications.  The unsync function may be NULL in which case
 *  the addresses requiring removal will simply be removed without
 *  any notification to the device.
 **/
int __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 *))
{
	struct netdev_hw_addr *ha, *tmp;
	int err;

	/* first go through and flush out any stale entries */
	list_for_each_entry_safe(ha, tmp, &list->list, list) {
		if (!ha->sync_cnt || ha->refcount != 1)
			continue;

		/* if unsync is defined and fails defer unsyncing address */
		if (unsync && unsync(dev, ha->addr))
			continue;

		ha->sync_cnt--;
		__hw_addr_del_entry(list, ha, false, false);
	}

	/* go through and sync new entries to the list */
	list_for_each_entry_safe(ha, tmp, &list->list, list) {
		if (ha->sync_cnt)
			continue;

		err = sync(dev, ha->addr);
		if (err)
			return err;

		ha->sync_cnt++;
		ha->refcount++;
	}

	return 0;
}
EXPORT_SYMBOL(__hw_addr_sync_dev);

/**
 *  __hw_addr_unsync_dev - Remove synchronized addresses from device
 *  @list: address list to remove synchronized addresses from
 *  @dev:  device to sync
 *  @unsync: function to call if address should be removed
 *
 *  Remove all addresses that were added to the device by __hw_addr_sync_dev().
 *  This function is intended to be called from the ndo_stop or ndo_open
 *  functions on devices that require explicit address add/remove
 *  notifications.  If the unsync function pointer is NULL then this function
 *  can be used to just reset the sync_cnt for the addresses in the list.
 **/
void __hw_addr_unsync_dev(struct netdev_hw_addr_list *list,
			  struct net_device *dev,
			  int (*unsync)(struct net_device *,
					const unsigned char *))
{
	struct netdev_hw_addr *ha, *tmp;

	list_for_each_entry_safe(ha, tmp, &list->list, list) {
		if (!ha->sync_cnt)
			continue;

		/* if unsync is defined and fails defer unsyncing address */
		if (unsync && unsync(dev, ha->addr))
			continue;

		ha->sync_cnt--;
		__hw_addr_del_entry(list, ha, false, false);
	}
}
EXPORT_SYMBOL(__hw_addr_unsync_dev);

static 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;
}

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, const 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, const 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 (!memcmp(ha->addr, addr, dev->addr_len) &&
	    ha->type == addr_type && 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);

/*
 * Unicast list handling functions
 */

/**
 *	dev_uc_add_excl - Add a global secondary unicast address
 *	@dev: device
 *	@addr: address to add
 */
int dev_uc_add_excl(struct net_device *dev, const unsigned char *addr)
{
	struct netdev_hw_addr *ha;
	int err;

	netif_addr_lock_bh(dev);
	list_for_each_entry(ha, &dev->uc.list, list) {
		if (!memcmp(ha->addr, addr, dev->addr_len) &&
		    ha->type == NETDEV_HW_ADDR_T_UNICAST) {
			err = -EEXIST;
			goto out;
		}
	}
	err = __hw_addr_create_ex(&dev->uc, addr, dev->addr_len,
				  NETDEV_HW_ADDR_T_UNICAST, true, false);
	if (!err)
		__dev_set_rx_mode(dev);
out:
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_uc_add_excl);

/**
 *	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, const 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, const 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_addr_lock_bh.
 *
 *	This function is intended to be called from the dev->set_rx_mode
 *	function of layered software devices.  This function assumes that
 *	addresses will only ever be synced to the @to devices and no other.
 */
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_nested(to);
	err = __hw_addr_sync(&to->uc, &from->uc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	return err;
}
EXPORT_SYMBOL(dev_uc_sync);

/**
 *	dev_uc_sync_multiple - Synchronize device's unicast list to another
 *	device, but allow for multiple calls to sync to multiple devices.
 *	@to: destination device
 *	@from: source device
 *
 *	Add newly added addresses to the destination device and release
 *	addresses that have been deleted from the source. The source device
 *	must be locked by netif_addr_lock_bh.
 *
 *	This function is intended to be called from the dev->set_rx_mode
 *	function of layered software devices.  It allows for a single source
 *	device to be synced to multiple destination devices.
 */
int dev_uc_sync_multiple(struct net_device *to, struct net_device *from)
{
	int err = 0;

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

	netif_addr_lock_nested(to);
	err = __hw_addr_sync_multiple(&to->uc, &from->uc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	return err;
}
EXPORT_SYMBOL(dev_uc_sync_multiple);

/**
 *	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_nested(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
 */

/**
 *	dev_mc_add_excl - Add a global secondary multicast address
 *	@dev: device
 *	@addr: address to add
 */
int dev_mc_add_excl(struct net_device *dev, const unsigned char *addr)
{
	struct netdev_hw_addr *ha;
	int err;

	netif_addr_lock_bh(dev);
	list_for_each_entry(ha, &dev->mc.list, list) {
		if (!memcmp(ha->addr, addr, dev->addr_len) &&
		    ha->type == NETDEV_HW_ADDR_T_MULTICAST) {
			err = -EEXIST;
			goto out;
		}
	}
	err = __hw_addr_create_ex(&dev->mc, addr, dev->addr_len,
				  NETDEV_HW_ADDR_T_MULTICAST, true, false);
	if (!err)
		__dev_set_rx_mode(dev);
out:
	netif_addr_unlock_bh(dev);
	return err;
}
EXPORT_SYMBOL(dev_mc_add_excl);

static int __dev_mc_add(struct net_device *dev, const 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, false, 0);
	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, const 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, const 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, const 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, false);
	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, const 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, const unsigned char *addr)
{
	return __dev_mc_del(dev, addr, true);
}
EXPORT_SYMBOL(dev_mc_del_global);

/**
 *	dev_mc_sync - Synchronize device's multicast 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_addr_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_nested(to);
	err = __hw_addr_sync(&to->mc, &from->mc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	return err;
}
EXPORT_SYMBOL(dev_mc_sync);

/**
 *	dev_mc_sync_multiple - Synchronize device's multicast list to another
 *	device, but allow for multiple calls to sync to multiple devices.
 *	@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_addr_lock_bh.
 *
 *	This function is intended to be called from the ndo_set_rx_mode
 *	function of layered software devices.  It allows for a single
 *	source device to be synced to multiple destination devices.
 */
int dev_mc_sync_multiple(struct net_device *to, struct net_device *from)
{
	int err = 0;

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

	netif_addr_lock_nested(to);
	err = __hw_addr_sync_multiple(&to->mc, &from->mc, to->addr_len);
	if (!err)
		__dev_set_rx_mode(to);
	netif_addr_unlock(to);
	return err;
}
EXPORT_SYMBOL(dev_mc_sync_multiple);

/**
 *	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_nested(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);