1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
   4 */
   5
   6#include <linux/skbuff.h>
   7#include <linux/netdevice.h>
   8#include <linux/etherdevice.h>
   9#include <linux/pkt_sched.h>
  10#include <linux/spinlock.h>
  11#include <linux/slab.h>
  12#include <linux/timer.h>
  13#include <linux/ip.h>
  14#include <linux/ipv6.h>
  15#include <linux/if_arp.h>
  16#include <linux/if_ether.h>
  17#include <linux/if_bonding.h>
  18#include <linux/if_vlan.h>
  19#include <linux/in.h>
 
  20#include <net/arp.h>
  21#include <net/ipv6.h>
  22#include <net/ndisc.h>
  23#include <asm/byteorder.h>
  24#include <net/bonding.h>
  25#include <net/bond_alb.h>
  26
  27static const u8 mac_v6_allmcast[ETH_ALEN + 2] __long_aligned = {
  28	0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  29};
  30static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  31
  32#pragma pack(1)
  33struct learning_pkt {
  34	u8 mac_dst[ETH_ALEN];
  35	u8 mac_src[ETH_ALEN];
  36	__be16 type;
  37	u8 padding[ETH_ZLEN - ETH_HLEN];
  38};
  39
  40struct arp_pkt {
  41	__be16  hw_addr_space;
  42	__be16  prot_addr_space;
  43	u8      hw_addr_len;
  44	u8      prot_addr_len;
  45	__be16  op_code;
  46	u8      mac_src[ETH_ALEN];	/* sender hardware address */
  47	__be32  ip_src;			/* sender IP address */
  48	u8      mac_dst[ETH_ALEN];	/* target hardware address */
  49	__be32  ip_dst;			/* target IP address */
  50};
  51#pragma pack()
  52
 
 
 
 
 
  53/* Forward declaration */
  54static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
  55				      bool strict_match);
  56static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  57static void rlb_src_unlink(struct bonding *bond, u32 index);
  58static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  59			 u32 ip_dst_hash);
  60
  61static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  62{
  63	int i;
  64	u8 hash = 0;
  65
  66	for (i = 0; i < hash_size; i++)
  67		hash ^= hash_start[i];
  68
  69	return hash;
  70}
  71
  72/*********************** tlb specific functions ***************************/
  73
  74static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
  75{
  76	if (save_load) {
  77		entry->load_history = 1 + entry->tx_bytes /
  78				      BOND_TLB_REBALANCE_INTERVAL;
  79		entry->tx_bytes = 0;
  80	}
  81
  82	entry->tx_slave = NULL;
  83	entry->next = TLB_NULL_INDEX;
  84	entry->prev = TLB_NULL_INDEX;
  85}
  86
  87static inline void tlb_init_slave(struct slave *slave)
  88{
  89	SLAVE_TLB_INFO(slave).load = 0;
  90	SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
  91}
  92
  93static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
  94			 int save_load)
  95{
  96	struct tlb_client_info *tx_hash_table;
  97	u32 index;
  98
  99	/* clear slave from tx_hashtbl */
 100	tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 101
 102	/* skip this if we've already freed the tx hash table */
 103	if (tx_hash_table) {
 104		index = SLAVE_TLB_INFO(slave).head;
 105		while (index != TLB_NULL_INDEX) {
 106			u32 next_index = tx_hash_table[index].next;
 107
 108			tlb_init_table_entry(&tx_hash_table[index], save_load);
 109			index = next_index;
 110		}
 111	}
 112
 113	tlb_init_slave(slave);
 114}
 115
 116static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 117			 int save_load)
 118{
 119	spin_lock_bh(&bond->mode_lock);
 120	__tlb_clear_slave(bond, slave, save_load);
 121	spin_unlock_bh(&bond->mode_lock);
 122}
 123
 124/* Must be called before starting the monitor timer */
 125static int tlb_initialize(struct bonding *bond)
 126{
 127	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 128	int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 129	struct tlb_client_info *new_hashtbl;
 130	int i;
 131
 132	new_hashtbl = kzalloc(size, GFP_KERNEL);
 133	if (!new_hashtbl)
 134		return -ENOMEM;
 135
 136	spin_lock_bh(&bond->mode_lock);
 137
 138	bond_info->tx_hashtbl = new_hashtbl;
 139
 140	for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
 141		tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 142
 143	spin_unlock_bh(&bond->mode_lock);
 144
 145	return 0;
 146}
 147
 148/* Must be called only after all slaves have been released */
 149static void tlb_deinitialize(struct bonding *bond)
 150{
 151	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 152
 153	spin_lock_bh(&bond->mode_lock);
 154
 155	kfree(bond_info->tx_hashtbl);
 156	bond_info->tx_hashtbl = NULL;
 157
 158	spin_unlock_bh(&bond->mode_lock);
 159}
 160
 161static long long compute_gap(struct slave *slave)
 162{
 163	return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 164	       (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 165}
 166
 167static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 168{
 169	struct slave *slave, *least_loaded;
 170	struct list_head *iter;
 171	long long max_gap;
 172
 173	least_loaded = NULL;
 174	max_gap = LLONG_MIN;
 175
 176	/* Find the slave with the largest gap */
 177	bond_for_each_slave_rcu(bond, slave, iter) {
 178		if (bond_slave_can_tx(slave)) {
 179			long long gap = compute_gap(slave);
 180
 181			if (max_gap < gap) {
 182				least_loaded = slave;
 183				max_gap = gap;
 184			}
 185		}
 186	}
 187
 188	return least_loaded;
 189}
 190
 191static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 192						u32 skb_len)
 193{
 194	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 195	struct tlb_client_info *hash_table;
 196	struct slave *assigned_slave;
 197
 198	hash_table = bond_info->tx_hashtbl;
 199	assigned_slave = hash_table[hash_index].tx_slave;
 200	if (!assigned_slave) {
 201		assigned_slave = tlb_get_least_loaded_slave(bond);
 202
 203		if (assigned_slave) {
 204			struct tlb_slave_info *slave_info =
 205				&(SLAVE_TLB_INFO(assigned_slave));
 206			u32 next_index = slave_info->head;
 207
 208			hash_table[hash_index].tx_slave = assigned_slave;
 209			hash_table[hash_index].next = next_index;
 210			hash_table[hash_index].prev = TLB_NULL_INDEX;
 211
 212			if (next_index != TLB_NULL_INDEX)
 213				hash_table[next_index].prev = hash_index;
 214
 215			slave_info->head = hash_index;
 216			slave_info->load +=
 217				hash_table[hash_index].load_history;
 218		}
 219	}
 220
 221	if (assigned_slave)
 222		hash_table[hash_index].tx_bytes += skb_len;
 223
 224	return assigned_slave;
 225}
 226
 227static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 228					u32 skb_len)
 229{
 230	struct slave *tx_slave;
 231
 232	/* We don't need to disable softirq here, because
 233	 * tlb_choose_channel() is only called by bond_alb_xmit()
 234	 * which already has softirq disabled.
 235	 */
 236	spin_lock(&bond->mode_lock);
 237	tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 238	spin_unlock(&bond->mode_lock);
 239
 240	return tx_slave;
 241}
 242
 243/*********************** rlb specific functions ***************************/
 244
 245/* when an ARP REPLY is received from a client update its info
 246 * in the rx_hashtbl
 247 */
 248static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 249{
 250	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 251	struct rlb_client_info *client_info;
 252	u32 hash_index;
 253
 254	spin_lock_bh(&bond->mode_lock);
 255
 256	hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 257	client_info = &(bond_info->rx_hashtbl[hash_index]);
 258
 259	if ((client_info->assigned) &&
 260	    (client_info->ip_src == arp->ip_dst) &&
 261	    (client_info->ip_dst == arp->ip_src) &&
 262	    (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
 263		/* update the clients MAC address */
 264		ether_addr_copy(client_info->mac_dst, arp->mac_src);
 265		client_info->ntt = 1;
 266		bond_info->rx_ntt = 1;
 267	}
 268
 269	spin_unlock_bh(&bond->mode_lock);
 270}
 271
 272static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
 273			struct slave *slave)
 274{
 275	struct arp_pkt *arp, _arp;
 276
 277	if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 278		goto out;
 279
 280	arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
 281	if (!arp)
 282		goto out;
 283
 284	/* We received an ARP from arp->ip_src.
 285	 * We might have used this IP address previously (on the bonding host
 286	 * itself or on a system that is bridged together with the bond).
 287	 * However, if arp->mac_src is different than what is stored in
 288	 * rx_hashtbl, some other host is now using the IP and we must prevent
 289	 * sending out client updates with this IP address and the old MAC
 290	 * address.
 291	 * Clean up all hash table entries that have this address as ip_src but
 292	 * have a different mac_src.
 293	 */
 294	rlb_purge_src_ip(bond, arp);
 295
 296	if (arp->op_code == htons(ARPOP_REPLY)) {
 297		/* update rx hash table for this ARP */
 298		rlb_update_entry_from_arp(bond, arp);
 299		slave_dbg(bond->dev, slave->dev, "Server received an ARP Reply from client\n");
 300	}
 301out:
 302	return RX_HANDLER_ANOTHER;
 303}
 304
 305/* Caller must hold rcu_read_lock() */
 306static struct slave *__rlb_next_rx_slave(struct bonding *bond)
 307{
 308	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 309	struct slave *before = NULL, *rx_slave = NULL, *slave;
 310	struct list_head *iter;
 311	bool found = false;
 312
 313	bond_for_each_slave_rcu(bond, slave, iter) {
 314		if (!bond_slave_can_tx(slave))
 315			continue;
 316		if (!found) {
 317			if (!before || before->speed < slave->speed)
 318				before = slave;
 319		} else {
 320			if (!rx_slave || rx_slave->speed < slave->speed)
 321				rx_slave = slave;
 322		}
 323		if (slave == bond_info->rx_slave)
 324			found = true;
 325	}
 326	/* we didn't find anything after the current or we have something
 327	 * better before and up to the current slave
 328	 */
 329	if (!rx_slave || (before && rx_slave->speed < before->speed))
 330		rx_slave = before;
 331
 332	if (rx_slave)
 333		bond_info->rx_slave = rx_slave;
 334
 335	return rx_slave;
 336}
 337
 338/* Caller must hold RTNL, rcu_read_lock is obtained only to silence checkers */
 339static struct slave *rlb_next_rx_slave(struct bonding *bond)
 340{
 341	struct slave *rx_slave;
 342
 343	ASSERT_RTNL();
 344
 345	rcu_read_lock();
 346	rx_slave = __rlb_next_rx_slave(bond);
 347	rcu_read_unlock();
 348
 349	return rx_slave;
 350}
 351
 352/* teach the switch the mac of a disabled slave
 353 * on the primary for fault tolerance
 354 *
 355 * Caller must hold RTNL
 356 */
 357static void rlb_teach_disabled_mac_on_primary(struct bonding *bond,
 358					      const u8 addr[])
 359{
 360	struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
 361
 362	if (!curr_active)
 363		return;
 364
 365	if (!bond->alb_info.primary_is_promisc) {
 366		if (!dev_set_promiscuity(curr_active->dev, 1))
 367			bond->alb_info.primary_is_promisc = 1;
 368		else
 369			bond->alb_info.primary_is_promisc = 0;
 370	}
 371
 372	bond->alb_info.rlb_promisc_timeout_counter = 0;
 373
 374	alb_send_learning_packets(curr_active, addr, true);
 375}
 376
 377/* slave being removed should not be active at this point
 378 *
 379 * Caller must hold rtnl.
 380 */
 381static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 382{
 383	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 384	struct rlb_client_info *rx_hash_table;
 385	u32 index, next_index;
 386
 387	/* clear slave from rx_hashtbl */
 388	spin_lock_bh(&bond->mode_lock);
 389
 390	rx_hash_table = bond_info->rx_hashtbl;
 391	index = bond_info->rx_hashtbl_used_head;
 392	for (; index != RLB_NULL_INDEX; index = next_index) {
 393		next_index = rx_hash_table[index].used_next;
 394		if (rx_hash_table[index].slave == slave) {
 395			struct slave *assigned_slave = rlb_next_rx_slave(bond);
 396
 397			if (assigned_slave) {
 398				rx_hash_table[index].slave = assigned_slave;
 399				if (is_valid_ether_addr(rx_hash_table[index].mac_dst)) {
 400					bond_info->rx_hashtbl[index].ntt = 1;
 401					bond_info->rx_ntt = 1;
 402					/* A slave has been removed from the
 403					 * table because it is either disabled
 404					 * or being released. We must retry the
 405					 * update to avoid clients from not
 406					 * being updated & disconnecting when
 407					 * there is stress
 408					 */
 409					bond_info->rlb_update_retry_counter =
 410						RLB_UPDATE_RETRY;
 411				}
 412			} else {  /* there is no active slave */
 413				rx_hash_table[index].slave = NULL;
 414			}
 415		}
 416	}
 417
 418	spin_unlock_bh(&bond->mode_lock);
 419
 420	if (slave != rtnl_dereference(bond->curr_active_slave))
 421		rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 422}
 423
 424static void rlb_update_client(struct rlb_client_info *client_info)
 425{
 426	int i;
 427
 428	if (!client_info->slave || !is_valid_ether_addr(client_info->mac_dst))
 429		return;
 430
 431	for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 432		struct sk_buff *skb;
 433
 434		skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 435				 client_info->ip_dst,
 436				 client_info->slave->dev,
 437				 client_info->ip_src,
 438				 client_info->mac_dst,
 439				 client_info->slave->dev->dev_addr,
 440				 client_info->mac_dst);
 441		if (!skb) {
 442			slave_err(client_info->slave->bond->dev,
 443				  client_info->slave->dev,
 444				  "failed to create an ARP packet\n");
 445			continue;
 446		}
 447
 448		skb->dev = client_info->slave->dev;
 449
 450		if (client_info->vlan_id) {
 451			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 452					       client_info->vlan_id);
 453		}
 454
 455		arp_xmit(skb);
 456	}
 457}
 458
 459/* sends ARP REPLIES that update the clients that need updating */
 460static void rlb_update_rx_clients(struct bonding *bond)
 461{
 462	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 463	struct rlb_client_info *client_info;
 464	u32 hash_index;
 465
 466	spin_lock_bh(&bond->mode_lock);
 467
 468	hash_index = bond_info->rx_hashtbl_used_head;
 469	for (; hash_index != RLB_NULL_INDEX;
 470	     hash_index = client_info->used_next) {
 471		client_info = &(bond_info->rx_hashtbl[hash_index]);
 472		if (client_info->ntt) {
 473			rlb_update_client(client_info);
 474			if (bond_info->rlb_update_retry_counter == 0)
 475				client_info->ntt = 0;
 476		}
 477	}
 478
 479	/* do not update the entries again until this counter is zero so that
 480	 * not to confuse the clients.
 481	 */
 482	bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 483
 484	spin_unlock_bh(&bond->mode_lock);
 485}
 486
 487/* The slave was assigned a new mac address - update the clients */
 488static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 489{
 490	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 491	struct rlb_client_info *client_info;
 492	int ntt = 0;
 493	u32 hash_index;
 494
 495	spin_lock_bh(&bond->mode_lock);
 496
 497	hash_index = bond_info->rx_hashtbl_used_head;
 498	for (; hash_index != RLB_NULL_INDEX;
 499	     hash_index = client_info->used_next) {
 500		client_info = &(bond_info->rx_hashtbl[hash_index]);
 501
 502		if ((client_info->slave == slave) &&
 503		    is_valid_ether_addr(client_info->mac_dst)) {
 504			client_info->ntt = 1;
 505			ntt = 1;
 506		}
 507	}
 508
 509	/* update the team's flag only after the whole iteration */
 510	if (ntt) {
 511		bond_info->rx_ntt = 1;
 512		/* fasten the change */
 513		bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 514	}
 515
 516	spin_unlock_bh(&bond->mode_lock);
 517}
 518
 519/* mark all clients using src_ip to be updated */
 520static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 521{
 522	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 523	struct rlb_client_info *client_info;
 524	u32 hash_index;
 525
 526	spin_lock(&bond->mode_lock);
 527
 528	hash_index = bond_info->rx_hashtbl_used_head;
 529	for (; hash_index != RLB_NULL_INDEX;
 530	     hash_index = client_info->used_next) {
 531		client_info = &(bond_info->rx_hashtbl[hash_index]);
 532
 533		if (!client_info->slave) {
 534			netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
 535			continue;
 536		}
 537		/* update all clients using this src_ip, that are not assigned
 538		 * to the team's address (curr_active_slave) and have a known
 539		 * unicast mac address.
 540		 */
 541		if ((client_info->ip_src == src_ip) &&
 542		    !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 543					     bond->dev->dev_addr) &&
 544		    is_valid_ether_addr(client_info->mac_dst)) {
 545			client_info->ntt = 1;
 546			bond_info->rx_ntt = 1;
 547		}
 548	}
 549
 550	spin_unlock(&bond->mode_lock);
 551}
 552
 553static struct slave *rlb_choose_channel(struct sk_buff *skb,
 554					struct bonding *bond,
 555					const struct arp_pkt *arp)
 556{
 557	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 
 558	struct slave *assigned_slave, *curr_active_slave;
 559	struct rlb_client_info *client_info;
 560	u32 hash_index = 0;
 561
 562	spin_lock(&bond->mode_lock);
 563
 564	curr_active_slave = rcu_dereference(bond->curr_active_slave);
 565
 566	hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 567	client_info = &(bond_info->rx_hashtbl[hash_index]);
 568
 569	if (client_info->assigned) {
 570		if ((client_info->ip_src == arp->ip_src) &&
 571		    (client_info->ip_dst == arp->ip_dst)) {
 572			/* the entry is already assigned to this client */
 573			if (!is_broadcast_ether_addr(arp->mac_dst)) {
 574				/* update mac address from arp */
 575				ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 576			}
 577			ether_addr_copy(client_info->mac_src, arp->mac_src);
 578
 579			assigned_slave = client_info->slave;
 580			if (assigned_slave) {
 581				spin_unlock(&bond->mode_lock);
 582				return assigned_slave;
 583			}
 584		} else {
 585			/* the entry is already assigned to some other client,
 586			 * move the old client to primary (curr_active_slave) so
 587			 * that the new client can be assigned to this entry.
 588			 */
 589			if (curr_active_slave &&
 590			    client_info->slave != curr_active_slave) {
 591				client_info->slave = curr_active_slave;
 592				rlb_update_client(client_info);
 593			}
 594		}
 595	}
 596	/* assign a new slave */
 597	assigned_slave = __rlb_next_rx_slave(bond);
 598
 599	if (assigned_slave) {
 600		if (!(client_info->assigned &&
 601		      client_info->ip_src == arp->ip_src)) {
 602			/* ip_src is going to be updated,
 603			 * fix the src hash list
 604			 */
 605			u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 606						    sizeof(arp->ip_src));
 607			rlb_src_unlink(bond, hash_index);
 608			rlb_src_link(bond, hash_src, hash_index);
 609		}
 610
 611		client_info->ip_src = arp->ip_src;
 612		client_info->ip_dst = arp->ip_dst;
 613		/* arp->mac_dst is broadcast for arp requests.
 614		 * will be updated with clients actual unicast mac address
 615		 * upon receiving an arp reply.
 616		 */
 617		ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 618		ether_addr_copy(client_info->mac_src, arp->mac_src);
 619		client_info->slave = assigned_slave;
 620
 621		if (is_valid_ether_addr(client_info->mac_dst)) {
 622			client_info->ntt = 1;
 623			bond->alb_info.rx_ntt = 1;
 624		} else {
 625			client_info->ntt = 0;
 626		}
 627
 628		if (vlan_get_tag(skb, &client_info->vlan_id))
 629			client_info->vlan_id = 0;
 630
 631		if (!client_info->assigned) {
 632			u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 633
 634			bond_info->rx_hashtbl_used_head = hash_index;
 635			client_info->used_next = prev_tbl_head;
 636			if (prev_tbl_head != RLB_NULL_INDEX) {
 637				bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 638					hash_index;
 639			}
 640			client_info->assigned = 1;
 641		}
 642	}
 643
 644	spin_unlock(&bond->mode_lock);
 645
 646	return assigned_slave;
 647}
 648
 649/* chooses (and returns) transmit channel for arp reply
 650 * does not choose channel for other arp types since they are
 651 * sent on the curr_active_slave
 652 */
 653static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 654{
 
 655	struct slave *tx_slave = NULL;
 656	struct net_device *dev;
 657	struct arp_pkt *arp;
 658
 659	if (!pskb_network_may_pull(skb, sizeof(*arp)))
 660		return NULL;
 661	arp = (struct arp_pkt *)skb_network_header(skb);
 662
 663	/* Don't modify or load balance ARPs that do not originate
 664	 * from the bond itself or a VLAN directly above the bond.
 665	 */
 666	if (!bond_slave_has_mac_rcu(bond, arp->mac_src))
 667		return NULL;
 668
 669	dev = ip_dev_find(dev_net(bond->dev), arp->ip_src);
 670	if (dev) {
 671		if (netif_is_any_bridge_master(dev)) {
 672			dev_put(dev);
 673			return NULL;
 674		}
 675		dev_put(dev);
 676	}
 677
 678	if (arp->op_code == htons(ARPOP_REPLY)) {
 679		/* the arp must be sent on the selected rx channel */
 680		tx_slave = rlb_choose_channel(skb, bond, arp);
 681		if (tx_slave)
 682			bond_hw_addr_copy(arp->mac_src, tx_slave->dev->dev_addr,
 683					  tx_slave->dev->addr_len);
 684		netdev_dbg(bond->dev, "(slave %s): Server sent ARP Reply packet\n",
 685			   tx_slave ? tx_slave->dev->name : "NULL");
 686	} else if (arp->op_code == htons(ARPOP_REQUEST)) {
 687		/* Create an entry in the rx_hashtbl for this client as a
 688		 * place holder.
 689		 * When the arp reply is received the entry will be updated
 690		 * with the correct unicast address of the client.
 691		 */
 692		tx_slave = rlb_choose_channel(skb, bond, arp);
 693
 694		/* The ARP reply packets must be delayed so that
 695		 * they can cancel out the influence of the ARP request.
 696		 */
 697		bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 698
 699		/* arp requests are broadcast and are sent on the primary
 700		 * the arp request will collapse all clients on the subnet to
 701		 * the primary slave. We must register these clients to be
 702		 * updated with their assigned mac.
 703		 */
 704		rlb_req_update_subnet_clients(bond, arp->ip_src);
 705		netdev_dbg(bond->dev, "(slave %s): Server sent ARP Request packet\n",
 706			   tx_slave ? tx_slave->dev->name : "NULL");
 707	}
 708
 709	return tx_slave;
 710}
 711
 712static void rlb_rebalance(struct bonding *bond)
 713{
 714	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 715	struct slave *assigned_slave;
 716	struct rlb_client_info *client_info;
 717	int ntt;
 718	u32 hash_index;
 719
 720	spin_lock_bh(&bond->mode_lock);
 721
 722	ntt = 0;
 723	hash_index = bond_info->rx_hashtbl_used_head;
 724	for (; hash_index != RLB_NULL_INDEX;
 725	     hash_index = client_info->used_next) {
 726		client_info = &(bond_info->rx_hashtbl[hash_index]);
 727		assigned_slave = __rlb_next_rx_slave(bond);
 728		if (assigned_slave && (client_info->slave != assigned_slave)) {
 729			client_info->slave = assigned_slave;
 730			if (!is_zero_ether_addr(client_info->mac_dst)) {
 731				client_info->ntt = 1;
 732				ntt = 1;
 733			}
 734		}
 735	}
 736
 737	/* update the team's flag only after the whole iteration */
 738	if (ntt)
 739		bond_info->rx_ntt = 1;
 740	spin_unlock_bh(&bond->mode_lock);
 741}
 742
 743/* Caller must hold mode_lock */
 744static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 745{
 746	entry->used_next = RLB_NULL_INDEX;
 747	entry->used_prev = RLB_NULL_INDEX;
 748	entry->assigned = 0;
 749	entry->slave = NULL;
 750	entry->vlan_id = 0;
 751}
 752static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 753{
 754	entry->src_first = RLB_NULL_INDEX;
 755	entry->src_prev = RLB_NULL_INDEX;
 756	entry->src_next = RLB_NULL_INDEX;
 757}
 758
 759static void rlb_init_table_entry(struct rlb_client_info *entry)
 760{
 761	memset(entry, 0, sizeof(struct rlb_client_info));
 762	rlb_init_table_entry_dst(entry);
 763	rlb_init_table_entry_src(entry);
 764}
 765
 766static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 767{
 768	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 769	u32 next_index = bond_info->rx_hashtbl[index].used_next;
 770	u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 771
 772	if (index == bond_info->rx_hashtbl_used_head)
 773		bond_info->rx_hashtbl_used_head = next_index;
 774	if (prev_index != RLB_NULL_INDEX)
 775		bond_info->rx_hashtbl[prev_index].used_next = next_index;
 776	if (next_index != RLB_NULL_INDEX)
 777		bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 778}
 779
 780/* unlink a rlb hash table entry from the src list */
 781static void rlb_src_unlink(struct bonding *bond, u32 index)
 782{
 783	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 784	u32 next_index = bond_info->rx_hashtbl[index].src_next;
 785	u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 786
 787	bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 788	bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 789
 790	if (next_index != RLB_NULL_INDEX)
 791		bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 792
 793	if (prev_index == RLB_NULL_INDEX)
 794		return;
 795
 796	/* is prev_index pointing to the head of this list? */
 797	if (bond_info->rx_hashtbl[prev_index].src_first == index)
 798		bond_info->rx_hashtbl[prev_index].src_first = next_index;
 799	else
 800		bond_info->rx_hashtbl[prev_index].src_next = next_index;
 801
 802}
 803
 804static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 805{
 806	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 807	struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 808
 809	rlb_delete_table_entry_dst(bond, index);
 810	rlb_init_table_entry_dst(entry);
 811
 812	rlb_src_unlink(bond, index);
 813}
 814
 815/* add the rx_hashtbl[ip_dst_hash] entry to the list
 816 * of entries with identical ip_src_hash
 817 */
 818static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 819{
 820	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 821	u32 next;
 822
 823	bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 824	next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 825	bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 826	if (next != RLB_NULL_INDEX)
 827		bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 828	bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 829}
 830
 831/* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
 832 * not match arp->mac_src
 833 */
 834static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 835{
 836	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 837	u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 838	u32 index;
 839
 840	spin_lock_bh(&bond->mode_lock);
 841
 842	index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 843	while (index != RLB_NULL_INDEX) {
 844		struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 845		u32 next_index = entry->src_next;
 846
 847		if (entry->ip_src == arp->ip_src &&
 848		    !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 849			rlb_delete_table_entry(bond, index);
 850		index = next_index;
 851	}
 852	spin_unlock_bh(&bond->mode_lock);
 853}
 854
 855static int rlb_initialize(struct bonding *bond)
 856{
 857	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 858	struct rlb_client_info	*new_hashtbl;
 859	int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 860	int i;
 861
 862	new_hashtbl = kmalloc(size, GFP_KERNEL);
 863	if (!new_hashtbl)
 864		return -1;
 865
 866	spin_lock_bh(&bond->mode_lock);
 867
 868	bond_info->rx_hashtbl = new_hashtbl;
 869
 870	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 871
 872	for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 873		rlb_init_table_entry(bond_info->rx_hashtbl + i);
 874
 875	spin_unlock_bh(&bond->mode_lock);
 876
 877	/* register to receive ARPs */
 878	bond->recv_probe = rlb_arp_recv;
 879
 880	return 0;
 881}
 882
 883static void rlb_deinitialize(struct bonding *bond)
 884{
 885	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 886
 887	spin_lock_bh(&bond->mode_lock);
 888
 889	kfree(bond_info->rx_hashtbl);
 890	bond_info->rx_hashtbl = NULL;
 891	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 892
 893	spin_unlock_bh(&bond->mode_lock);
 894}
 895
 896static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 897{
 898	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 899	u32 curr_index;
 900
 901	spin_lock_bh(&bond->mode_lock);
 902
 903	curr_index = bond_info->rx_hashtbl_used_head;
 904	while (curr_index != RLB_NULL_INDEX) {
 905		struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 906		u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 907
 908		if (curr->vlan_id == vlan_id)
 909			rlb_delete_table_entry(bond, curr_index);
 910
 911		curr_index = next_index;
 912	}
 913
 914	spin_unlock_bh(&bond->mode_lock);
 915}
 916
 917/*********************** tlb/rlb shared functions *********************/
 918
 919static void alb_send_lp_vid(struct slave *slave, const u8 mac_addr[],
 920			    __be16 vlan_proto, u16 vid)
 921{
 922	struct learning_pkt pkt;
 923	struct sk_buff *skb;
 924	int size = sizeof(struct learning_pkt);
 925
 926	memset(&pkt, 0, size);
 927	ether_addr_copy(pkt.mac_dst, mac_addr);
 928	ether_addr_copy(pkt.mac_src, mac_addr);
 929	pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
 930
 931	skb = dev_alloc_skb(size);
 932	if (!skb)
 933		return;
 934
 935	skb_put_data(skb, &pkt, size);
 936
 937	skb_reset_mac_header(skb);
 938	skb->network_header = skb->mac_header + ETH_HLEN;
 939	skb->protocol = pkt.type;
 940	skb->priority = TC_PRIO_CONTROL;
 941	skb->dev = slave->dev;
 942
 943	slave_dbg(slave->bond->dev, slave->dev,
 944		  "Send learning packet: mac %pM vlan %d\n", mac_addr, vid);
 945
 946	if (vid)
 947		__vlan_hwaccel_put_tag(skb, vlan_proto, vid);
 948
 949	dev_queue_xmit(skb);
 950}
 951
 952struct alb_walk_data {
 953	struct bonding *bond;
 954	struct slave *slave;
 955	const u8 *mac_addr;
 956	bool strict_match;
 957};
 958
 959static int alb_upper_dev_walk(struct net_device *upper,
 960			      struct netdev_nested_priv *priv)
 961{
 962	struct alb_walk_data *data = (struct alb_walk_data *)priv->data;
 963	bool strict_match = data->strict_match;
 964	const u8 *mac_addr = data->mac_addr;
 965	struct bonding *bond = data->bond;
 966	struct slave *slave = data->slave;
 
 967	struct bond_vlan_tag *tags;
 968
 969	if (is_vlan_dev(upper) &&
 970	    bond->dev->lower_level == upper->lower_level - 1) {
 971		if (upper->addr_assign_type == NET_ADDR_STOLEN) {
 972			alb_send_lp_vid(slave, mac_addr,
 973					vlan_dev_vlan_proto(upper),
 974					vlan_dev_vlan_id(upper));
 975		} else {
 976			alb_send_lp_vid(slave, upper->dev_addr,
 977					vlan_dev_vlan_proto(upper),
 978					vlan_dev_vlan_id(upper));
 979		}
 980	}
 981
 982	/* If this is a macvlan device, then only send updates
 983	 * when strict_match is turned off.
 984	 */
 985	if (netif_is_macvlan(upper) && !strict_match) {
 986		tags = bond_verify_device_path(bond->dev, upper, 0);
 987		if (IS_ERR_OR_NULL(tags))
 988			return -ENOMEM;
 989
 990		alb_send_lp_vid(slave, upper->dev_addr,
 991				tags[0].vlan_proto, tags[0].vlan_id);
 992		kfree(tags);
 993	}
 994
 995	return 0;
 996}
 997
 998static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
 999				      bool strict_match)
1000{
1001	struct bonding *bond = bond_get_bond_by_slave(slave);
1002	struct netdev_nested_priv priv;
1003	struct alb_walk_data data = {
1004		.strict_match = strict_match,
1005		.mac_addr = mac_addr,
1006		.slave = slave,
1007		.bond = bond,
1008	};
1009
1010	priv.data = (void *)&data;
1011	/* send untagged */
1012	alb_send_lp_vid(slave, mac_addr, 0, 0);
1013
1014	/* loop through all devices and see if we need to send a packet
1015	 * for that device.
1016	 */
1017	rcu_read_lock();
1018	netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &priv);
1019	rcu_read_unlock();
1020}
1021
1022static int alb_set_slave_mac_addr(struct slave *slave, const u8 addr[],
1023				  unsigned int len)
1024{
1025	struct net_device *dev = slave->dev;
1026	struct sockaddr_storage ss;
1027
1028	if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1029		__dev_addr_set(dev, addr, len);
1030		return 0;
1031	}
1032
1033	/* for rlb each slave must have a unique hw mac addresses so that
1034	 * each slave will receive packets destined to a different mac
1035	 */
1036	memcpy(ss.__data, addr, len);
1037	ss.ss_family = dev->type;
1038	if (dev_set_mac_address(dev, (struct sockaddr *)&ss, NULL)) {
1039		slave_err(slave->bond->dev, dev, "dev_set_mac_address on slave failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n");
1040		return -EOPNOTSUPP;
1041	}
1042	return 0;
1043}
1044
1045/* Swap MAC addresses between two slaves.
1046 *
1047 * Called with RTNL held, and no other locks.
1048 */
1049static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1050{
1051	u8 tmp_mac_addr[MAX_ADDR_LEN];
1052
1053	bond_hw_addr_copy(tmp_mac_addr, slave1->dev->dev_addr,
1054			  slave1->dev->addr_len);
1055	alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr,
1056			       slave2->dev->addr_len);
1057	alb_set_slave_mac_addr(slave2, tmp_mac_addr,
1058			       slave1->dev->addr_len);
1059
1060}
1061
1062/* Send learning packets after MAC address swap.
1063 *
1064 * Called with RTNL and no other locks
1065 */
1066static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1067				struct slave *slave2)
1068{
1069	int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1070	struct slave *disabled_slave = NULL;
1071
1072	ASSERT_RTNL();
1073
1074	/* fasten the change in the switch */
1075	if (bond_slave_can_tx(slave1)) {
1076		alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1077		if (bond->alb_info.rlb_enabled) {
1078			/* inform the clients that the mac address
1079			 * has changed
1080			 */
1081			rlb_req_update_slave_clients(bond, slave1);
1082		}
1083	} else {
1084		disabled_slave = slave1;
1085	}
1086
1087	if (bond_slave_can_tx(slave2)) {
1088		alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1089		if (bond->alb_info.rlb_enabled) {
1090			/* inform the clients that the mac address
1091			 * has changed
1092			 */
1093			rlb_req_update_slave_clients(bond, slave2);
1094		}
1095	} else {
1096		disabled_slave = slave2;
1097	}
1098
1099	if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1100		/* A disabled slave was assigned an active mac addr */
1101		rlb_teach_disabled_mac_on_primary(bond,
1102						  disabled_slave->dev->dev_addr);
1103	}
1104}
1105
1106/**
1107 * alb_change_hw_addr_on_detach
1108 * @bond: bonding we're working on
1109 * @slave: the slave that was just detached
1110 *
1111 * We assume that @slave was already detached from the slave list.
1112 *
1113 * If @slave's permanent hw address is different both from its current
1114 * address and from @bond's address, then somewhere in the bond there's
1115 * a slave that has @slave's permanet address as its current address.
1116 * We'll make sure that slave no longer uses @slave's permanent address.
1117 *
1118 * Caller must hold RTNL and no other locks
1119 */
1120static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1121{
1122	int perm_curr_diff;
1123	int perm_bond_diff;
1124	struct slave *found_slave;
1125
1126	perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1127						  slave->dev->dev_addr);
1128	perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1129						  bond->dev->dev_addr);
1130
1131	if (perm_curr_diff && perm_bond_diff) {
1132		found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1133
1134		if (found_slave) {
1135			alb_swap_mac_addr(slave, found_slave);
1136			alb_fasten_mac_swap(bond, slave, found_slave);
1137		}
1138	}
1139}
1140
1141/**
1142 * alb_handle_addr_collision_on_attach
1143 * @bond: bonding we're working on
1144 * @slave: the slave that was just attached
1145 *
1146 * checks uniqueness of slave's mac address and handles the case the
1147 * new slave uses the bonds mac address.
1148 *
1149 * If the permanent hw address of @slave is @bond's hw address, we need to
1150 * find a different hw address to give @slave, that isn't in use by any other
1151 * slave in the bond. This address must be, of course, one of the permanent
1152 * addresses of the other slaves.
1153 *
1154 * We go over the slave list, and for each slave there we compare its
1155 * permanent hw address with the current address of all the other slaves.
1156 * If no match was found, then we've found a slave with a permanent address
1157 * that isn't used by any other slave in the bond, so we can assign it to
1158 * @slave.
1159 *
1160 * assumption: this function is called before @slave is attached to the
1161 *	       bond slave list.
1162 */
1163static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1164{
1165	struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1166	struct slave *tmp_slave1, *free_mac_slave = NULL;
1167	struct list_head *iter;
1168
1169	if (!bond_has_slaves(bond)) {
1170		/* this is the first slave */
1171		return 0;
1172	}
1173
1174	/* if slave's mac address differs from bond's mac address
1175	 * check uniqueness of slave's mac address against the other
1176	 * slaves in the bond.
1177	 */
1178	if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1179		if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1180			return 0;
1181
1182		/* Try setting slave mac to bond address and fall-through
1183		 * to code handling that situation below...
1184		 */
1185		alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1186				       bond->dev->addr_len);
1187	}
1188
1189	/* The slave's address is equal to the address of the bond.
1190	 * Search for a spare address in the bond for this slave.
1191	 */
1192	bond_for_each_slave(bond, tmp_slave1, iter) {
1193		if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1194			/* no slave has tmp_slave1's perm addr
1195			 * as its curr addr
1196			 */
1197			free_mac_slave = tmp_slave1;
1198			break;
1199		}
1200
1201		if (!has_bond_addr) {
1202			if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1203						    bond->dev->dev_addr)) {
1204
1205				has_bond_addr = tmp_slave1;
1206			}
1207		}
1208	}
1209
1210	if (free_mac_slave) {
1211		alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1212				       free_mac_slave->dev->addr_len);
1213
1214		slave_warn(bond->dev, slave->dev, "the slave hw address is in use by the bond; giving it the hw address of %s\n",
1215			   free_mac_slave->dev->name);
1216
1217	} else if (has_bond_addr) {
1218		slave_err(bond->dev, slave->dev, "the slave hw address is in use by the bond; couldn't find a slave with a free hw address to give it (this should not have happened)\n");
1219		return -EFAULT;
1220	}
1221
1222	return 0;
1223}
1224
1225/**
1226 * alb_set_mac_address
1227 * @bond: bonding we're working on
1228 * @addr: MAC address to set
1229 *
1230 * In TLB mode all slaves are configured to the bond's hw address, but set
1231 * their dev_addr field to different addresses (based on their permanent hw
1232 * addresses).
1233 *
1234 * For each slave, this function sets the interface to the new address and then
1235 * changes its dev_addr field to its previous value.
1236 *
1237 * Unwinding assumes bond's mac address has not yet changed.
1238 */
1239static int alb_set_mac_address(struct bonding *bond, void *addr)
1240{
1241	struct slave *slave, *rollback_slave;
1242	struct list_head *iter;
1243	struct sockaddr_storage ss;
1244	char tmp_addr[MAX_ADDR_LEN];
1245	int res;
1246
1247	if (bond->alb_info.rlb_enabled)
1248		return 0;
1249
1250	bond_for_each_slave(bond, slave, iter) {
1251		/* save net_device's current hw address */
1252		bond_hw_addr_copy(tmp_addr, slave->dev->dev_addr,
1253				  slave->dev->addr_len);
1254
1255		res = dev_set_mac_address(slave->dev, addr, NULL);
1256
1257		/* restore net_device's hw address */
1258		dev_addr_set(slave->dev, tmp_addr);
 
1259
1260		if (res)
1261			goto unwind;
1262	}
1263
1264	return 0;
1265
1266unwind:
1267	memcpy(ss.__data, bond->dev->dev_addr, bond->dev->addr_len);
1268	ss.ss_family = bond->dev->type;
1269
1270	/* unwind from head to the slave that failed */
1271	bond_for_each_slave(bond, rollback_slave, iter) {
1272		if (rollback_slave == slave)
1273			break;
1274		bond_hw_addr_copy(tmp_addr, rollback_slave->dev->dev_addr,
1275				  rollback_slave->dev->addr_len);
1276		dev_set_mac_address(rollback_slave->dev,
1277				    (struct sockaddr *)&ss, NULL);
1278		dev_addr_set(rollback_slave->dev, tmp_addr);
 
1279	}
1280
1281	return res;
1282}
1283
1284/* determine if the packet is NA or NS */
1285static bool alb_determine_nd(struct sk_buff *skb, struct bonding *bond)
1286{
1287	struct ipv6hdr *ip6hdr;
1288	struct icmp6hdr *hdr;
1289
1290	if (!pskb_network_may_pull(skb, sizeof(*ip6hdr)))
1291		return true;
1292
1293	ip6hdr = ipv6_hdr(skb);
1294	if (ip6hdr->nexthdr != IPPROTO_ICMPV6)
1295		return false;
1296
1297	if (!pskb_network_may_pull(skb, sizeof(*ip6hdr) + sizeof(*hdr)))
1298		return true;
1299
1300	hdr = icmp6_hdr(skb);
1301	return hdr->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT ||
1302		hdr->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION;
1303}
1304
1305/************************ exported alb functions ************************/
1306
1307int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1308{
1309	int res;
1310
1311	res = tlb_initialize(bond);
1312	if (res)
1313		return res;
1314
1315	if (rlb_enabled) {
 
1316		res = rlb_initialize(bond);
1317		if (res) {
1318			tlb_deinitialize(bond);
1319			return res;
1320		}
1321		bond->alb_info.rlb_enabled = 1;
1322	} else {
1323		bond->alb_info.rlb_enabled = 0;
1324	}
1325
1326	return 0;
1327}
1328
1329void bond_alb_deinitialize(struct bonding *bond)
1330{
1331	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1332
1333	tlb_deinitialize(bond);
1334
1335	if (bond_info->rlb_enabled)
1336		rlb_deinitialize(bond);
1337}
1338
1339static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1340				    struct slave *tx_slave)
1341{
1342	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1343	struct ethhdr *eth_data = eth_hdr(skb);
1344
1345	if (!tx_slave) {
1346		/* unbalanced or unassigned, send through primary */
1347		tx_slave = rcu_dereference(bond->curr_active_slave);
1348		if (bond->params.tlb_dynamic_lb)
1349			bond_info->unbalanced_load += skb->len;
1350	}
1351
1352	if (tx_slave && bond_slave_can_tx(tx_slave)) {
1353		if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1354			ether_addr_copy(eth_data->h_source,
1355					tx_slave->dev->dev_addr);
1356		}
1357
1358		return bond_dev_queue_xmit(bond, skb, tx_slave->dev);
 
1359	}
1360
1361	if (tx_slave && bond->params.tlb_dynamic_lb) {
1362		spin_lock(&bond->mode_lock);
1363		__tlb_clear_slave(bond, tx_slave, 0);
1364		spin_unlock(&bond->mode_lock);
1365	}
1366
1367	/* no suitable interface, frame not sent */
1368	return bond_tx_drop(bond->dev, skb);
 
 
1369}
1370
1371struct slave *bond_xmit_tlb_slave_get(struct bonding *bond,
1372				      struct sk_buff *skb)
1373{
1374	struct slave *tx_slave = NULL;
1375	struct ethhdr *eth_data;
 
1376	u32 hash_index;
1377
1378	skb_reset_mac_header(skb);
1379	eth_data = eth_hdr(skb);
1380
1381	/* Do not TX balance any multicast or broadcast */
1382	if (!is_multicast_ether_addr(eth_data->h_dest)) {
1383		switch (skb->protocol) {
1384		case htons(ETH_P_IPV6):
1385			if (alb_determine_nd(skb, bond))
1386				break;
1387			fallthrough;
1388		case htons(ETH_P_IP):
 
 
 
1389			hash_index = bond_xmit_hash(bond, skb);
1390			if (bond->params.tlb_dynamic_lb) {
1391				tx_slave = tlb_choose_channel(bond,
1392							      hash_index & 0xFF,
1393							      skb->len);
1394			} else {
1395				struct bond_up_slave *slaves;
1396				unsigned int count;
1397
1398				slaves = rcu_dereference(bond->usable_slaves);
1399				count = slaves ? READ_ONCE(slaves->count) : 0;
1400				if (likely(count))
1401					tx_slave = slaves->arr[hash_index %
1402							       count];
1403			}
1404			break;
1405		}
1406	}
1407	return tx_slave;
1408}
1409
1410netdev_tx_t bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1411{
1412	struct bonding *bond = netdev_priv(bond_dev);
1413	struct slave *tx_slave;
1414
1415	tx_slave = bond_xmit_tlb_slave_get(bond, skb);
1416	return bond_do_alb_xmit(skb, bond, tx_slave);
1417}
1418
1419struct slave *bond_xmit_alb_slave_get(struct bonding *bond,
1420				      struct sk_buff *skb)
1421{
 
 
1422	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1423	static const __be32 ip_bcast = htonl(0xffffffff);
1424	struct slave *tx_slave = NULL;
1425	const u8 *hash_start = NULL;
 
1426	bool do_tx_balance = true;
1427	struct ethhdr *eth_data;
1428	u32 hash_index = 0;
1429	int hash_size = 0;
 
1430
1431	skb_reset_mac_header(skb);
1432	eth_data = eth_hdr(skb);
1433
1434	switch (ntohs(skb->protocol)) {
1435	case ETH_P_IP: {
1436		const struct iphdr *iph;
1437
1438		if (is_broadcast_ether_addr(eth_data->h_dest) ||
1439		    !pskb_network_may_pull(skb, sizeof(*iph))) {
1440			do_tx_balance = false;
1441			break;
1442		}
1443		iph = ip_hdr(skb);
1444		if (iph->daddr == ip_bcast || iph->protocol == IPPROTO_IGMP) {
1445			do_tx_balance = false;
1446			break;
1447		}
1448		hash_start = (char *)&(iph->daddr);
1449		hash_size = sizeof(iph->daddr);
1450		break;
1451	}
1452	case ETH_P_IPV6: {
1453		const struct ipv6hdr *ip6hdr;
1454
1455		/* IPv6 doesn't really use broadcast mac address, but leave
1456		 * that here just in case.
1457		 */
1458		if (is_broadcast_ether_addr(eth_data->h_dest)) {
1459			do_tx_balance = false;
1460			break;
1461		}
1462
1463		/* IPv6 uses all-nodes multicast as an equivalent to
1464		 * broadcasts in IPv4.
1465		 */
1466		if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1467			do_tx_balance = false;
1468			break;
1469		}
1470
1471		if (alb_determine_nd(skb, bond)) {
1472			do_tx_balance = false;
1473			break;
1474		}
1475
1476		/* The IPv6 header is pulled by alb_determine_nd */
1477		/* Additionally, DAD probes should not be tx-balanced as that
1478		 * will lead to false positives for duplicate addresses and
1479		 * prevent address configuration from working.
1480		 */
1481		ip6hdr = ipv6_hdr(skb);
1482		if (ipv6_addr_any(&ip6hdr->saddr)) {
1483			do_tx_balance = false;
1484			break;
1485		}
1486
1487		hash_start = (char *)&ip6hdr->daddr;
1488		hash_size = sizeof(ip6hdr->daddr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1489		break;
1490	}
1491	case ETH_P_ARP:
1492		do_tx_balance = false;
1493		if (bond_info->rlb_enabled)
1494			tx_slave = rlb_arp_xmit(skb, bond);
1495		break;
1496	default:
1497		do_tx_balance = false;
1498		break;
1499	}
1500
1501	if (do_tx_balance) {
1502		if (bond->params.tlb_dynamic_lb) {
1503			hash_index = _simple_hash(hash_start, hash_size);
1504			tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1505		} else {
1506			/*
1507			 * do_tx_balance means we are free to select the tx_slave
1508			 * So we do exactly what tlb would do for hash selection
1509			 */
1510
1511			struct bond_up_slave *slaves;
1512			unsigned int count;
1513
1514			slaves = rcu_dereference(bond->usable_slaves);
1515			count = slaves ? READ_ONCE(slaves->count) : 0;
1516			if (likely(count))
1517				tx_slave = slaves->arr[bond_xmit_hash(bond, skb) %
1518						       count];
1519		}
1520	}
1521	return tx_slave;
1522}
1523
1524netdev_tx_t bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1525{
1526	struct bonding *bond = netdev_priv(bond_dev);
1527	struct slave *tx_slave = NULL;
1528
1529	tx_slave = bond_xmit_alb_slave_get(bond, skb);
1530	return bond_do_alb_xmit(skb, bond, tx_slave);
1531}
1532
1533void bond_alb_monitor(struct work_struct *work)
1534{
1535	struct bonding *bond = container_of(work, struct bonding,
1536					    alb_work.work);
1537	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1538	struct list_head *iter;
1539	struct slave *slave;
1540
1541	if (!bond_has_slaves(bond)) {
1542		atomic_set(&bond_info->tx_rebalance_counter, 0);
1543		bond_info->lp_counter = 0;
1544		goto re_arm;
1545	}
1546
1547	rcu_read_lock();
1548
1549	atomic_inc(&bond_info->tx_rebalance_counter);
1550	bond_info->lp_counter++;
1551
1552	/* send learning packets */
1553	if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1554		bool strict_match;
1555
1556		bond_for_each_slave_rcu(bond, slave, iter) {
1557			/* If updating current_active, use all currently
1558			 * user mac addresses (!strict_match).  Otherwise, only
1559			 * use mac of the slave device.
1560			 * In RLB mode, we always use strict matches.
1561			 */
1562			strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1563					bond_info->rlb_enabled);
1564			alb_send_learning_packets(slave, slave->dev->dev_addr,
1565						  strict_match);
1566		}
1567		bond_info->lp_counter = 0;
1568	}
1569
1570	/* rebalance tx traffic */
1571	if (atomic_read(&bond_info->tx_rebalance_counter) >= BOND_TLB_REBALANCE_TICKS) {
1572		bond_for_each_slave_rcu(bond, slave, iter) {
1573			tlb_clear_slave(bond, slave, 1);
1574			if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1575				SLAVE_TLB_INFO(slave).load =
1576					bond_info->unbalanced_load /
1577						BOND_TLB_REBALANCE_INTERVAL;
1578				bond_info->unbalanced_load = 0;
1579			}
1580		}
1581		atomic_set(&bond_info->tx_rebalance_counter, 0);
1582	}
1583
1584	if (bond_info->rlb_enabled) {
1585		if (bond_info->primary_is_promisc &&
1586		    (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1587
1588			/* dev_set_promiscuity requires rtnl and
1589			 * nothing else.  Avoid race with bond_close.
1590			 */
1591			rcu_read_unlock();
1592			if (!rtnl_trylock())
1593				goto re_arm;
1594
1595			bond_info->rlb_promisc_timeout_counter = 0;
1596
1597			/* If the primary was set to promiscuous mode
1598			 * because a slave was disabled then
1599			 * it can now leave promiscuous mode.
1600			 */
1601			dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1602					    -1);
1603			bond_info->primary_is_promisc = 0;
1604
1605			rtnl_unlock();
1606			rcu_read_lock();
1607		}
1608
1609		if (bond_info->rlb_rebalance) {
1610			bond_info->rlb_rebalance = 0;
1611			rlb_rebalance(bond);
1612		}
1613
1614		/* check if clients need updating */
1615		if (bond_info->rx_ntt) {
1616			if (bond_info->rlb_update_delay_counter) {
1617				--bond_info->rlb_update_delay_counter;
1618			} else {
1619				rlb_update_rx_clients(bond);
1620				if (bond_info->rlb_update_retry_counter)
1621					--bond_info->rlb_update_retry_counter;
1622				else
1623					bond_info->rx_ntt = 0;
1624			}
1625		}
1626	}
1627	rcu_read_unlock();
1628re_arm:
1629	queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1630}
1631
1632/* assumption: called before the slave is attached to the bond
1633 * and not locked by the bond lock
1634 */
1635int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1636{
1637	int res;
1638
1639	res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1640				     slave->dev->addr_len);
1641	if (res)
1642		return res;
1643
1644	res = alb_handle_addr_collision_on_attach(bond, slave);
1645	if (res)
1646		return res;
1647
1648	tlb_init_slave(slave);
1649
1650	/* order a rebalance ASAP */
1651	atomic_set(&bond->alb_info.tx_rebalance_counter,
1652		   BOND_TLB_REBALANCE_TICKS);
1653
1654	if (bond->alb_info.rlb_enabled)
1655		bond->alb_info.rlb_rebalance = 1;
1656
1657	return 0;
1658}
1659
1660/* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1661 * if necessary.
1662 *
1663 * Caller must hold RTNL and no other locks
1664 */
1665void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1666{
1667	if (bond_has_slaves(bond))
1668		alb_change_hw_addr_on_detach(bond, slave);
1669
1670	tlb_clear_slave(bond, slave, 0);
1671
1672	if (bond->alb_info.rlb_enabled) {
1673		bond->alb_info.rx_slave = NULL;
1674		rlb_clear_slave(bond, slave);
1675	}
1676
1677}
1678
1679void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1680{
1681	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1682
1683	if (link == BOND_LINK_DOWN) {
1684		tlb_clear_slave(bond, slave, 0);
1685		if (bond->alb_info.rlb_enabled)
1686			rlb_clear_slave(bond, slave);
1687	} else if (link == BOND_LINK_UP) {
1688		/* order a rebalance ASAP */
1689		atomic_set(&bond_info->tx_rebalance_counter,
1690			   BOND_TLB_REBALANCE_TICKS);
1691		if (bond->alb_info.rlb_enabled) {
1692			bond->alb_info.rlb_rebalance = 1;
1693			/* If the updelay module parameter is smaller than the
1694			 * forwarding delay of the switch the rebalance will
1695			 * not work because the rebalance arp replies will
1696			 * not be forwarded to the clients..
1697			 */
1698		}
1699	}
1700
1701	if (bond_is_nondyn_tlb(bond)) {
1702		if (bond_update_slave_arr(bond, NULL))
1703			pr_err("Failed to build slave-array for TLB mode.\n");
1704	}
1705}
1706
1707/**
1708 * bond_alb_handle_active_change - assign new curr_active_slave
1709 * @bond: our bonding struct
1710 * @new_slave: new slave to assign
1711 *
1712 * Set the bond->curr_active_slave to @new_slave and handle
1713 * mac address swapping and promiscuity changes as needed.
1714 *
1715 * Caller must hold RTNL
1716 */
1717void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1718{
1719	struct slave *swap_slave;
1720	struct slave *curr_active;
1721
1722	curr_active = rtnl_dereference(bond->curr_active_slave);
1723	if (curr_active == new_slave)
1724		return;
1725
1726	if (curr_active && bond->alb_info.primary_is_promisc) {
1727		dev_set_promiscuity(curr_active->dev, -1);
1728		bond->alb_info.primary_is_promisc = 0;
1729		bond->alb_info.rlb_promisc_timeout_counter = 0;
1730	}
1731
1732	swap_slave = curr_active;
1733	rcu_assign_pointer(bond->curr_active_slave, new_slave);
1734
1735	if (!new_slave || !bond_has_slaves(bond))
1736		return;
1737
1738	/* set the new curr_active_slave to the bonds mac address
1739	 * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1740	 */
1741	if (!swap_slave)
1742		swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1743
1744	/* Arrange for swap_slave and new_slave to temporarily be
1745	 * ignored so we can mess with their MAC addresses without
1746	 * fear of interference from transmit activity.
1747	 */
1748	if (swap_slave)
1749		tlb_clear_slave(bond, swap_slave, 1);
1750	tlb_clear_slave(bond, new_slave, 1);
1751
1752	/* in TLB mode, the slave might flip down/up with the old dev_addr,
1753	 * and thus filter bond->dev_addr's packets, so force bond's mac
1754	 */
1755	if (BOND_MODE(bond) == BOND_MODE_TLB) {
1756		struct sockaddr_storage ss;
1757		u8 tmp_addr[MAX_ADDR_LEN];
1758
1759		bond_hw_addr_copy(tmp_addr, new_slave->dev->dev_addr,
1760				  new_slave->dev->addr_len);
1761
1762		bond_hw_addr_copy(ss.__data, bond->dev->dev_addr,
1763				  bond->dev->addr_len);
1764		ss.ss_family = bond->dev->type;
1765		/* we don't care if it can't change its mac, best effort */
1766		dev_set_mac_address(new_slave->dev, (struct sockaddr *)&ss,
1767				    NULL);
1768
1769		dev_addr_set(new_slave->dev, tmp_addr);
 
1770	}
1771
1772	/* curr_active_slave must be set before calling alb_swap_mac_addr */
1773	if (swap_slave) {
1774		/* swap mac address */
1775		alb_swap_mac_addr(swap_slave, new_slave);
1776		alb_fasten_mac_swap(bond, swap_slave, new_slave);
1777	} else {
1778		/* set the new_slave to the bond mac address */
1779		alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1780				       bond->dev->addr_len);
1781		alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1782					  false);
1783	}
1784}
1785
1786/* Called with RTNL */
1787int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1788{
1789	struct bonding *bond = netdev_priv(bond_dev);
1790	struct sockaddr_storage *ss = addr;
1791	struct slave *curr_active;
1792	struct slave *swap_slave;
1793	int res;
1794
1795	if (!is_valid_ether_addr(ss->__data))
1796		return -EADDRNOTAVAIL;
1797
1798	res = alb_set_mac_address(bond, addr);
1799	if (res)
1800		return res;
1801
1802	dev_addr_set(bond_dev, ss->__data);
1803
1804	/* If there is no curr_active_slave there is nothing else to do.
1805	 * Otherwise we'll need to pass the new address to it and handle
1806	 * duplications.
1807	 */
1808	curr_active = rtnl_dereference(bond->curr_active_slave);
1809	if (!curr_active)
1810		return 0;
1811
1812	swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1813
1814	if (swap_slave) {
1815		alb_swap_mac_addr(swap_slave, curr_active);
1816		alb_fasten_mac_swap(bond, swap_slave, curr_active);
1817	} else {
1818		alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr,
1819				       bond_dev->addr_len);
1820
1821		alb_send_learning_packets(curr_active,
1822					  bond_dev->dev_addr, false);
1823		if (bond->alb_info.rlb_enabled) {
1824			/* inform clients mac address has changed */
1825			rlb_req_update_slave_clients(bond, curr_active);
1826		}
1827	}
1828
1829	return 0;
1830}
1831
1832void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1833{
1834	if (bond->alb_info.rlb_enabled)
1835		rlb_clear_vlan(bond, vlan_id);
1836}
1837