drivers/net/bonding/bond_alb.c

   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
  27 static const u8 mac_v6_allmcast[ETH_ALEN + 2] __long_aligned = {
  28         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  29 };
  30 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  31
  32 #pragma pack(1)
  33 struct 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
  40 struct 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 */
  54 static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
  55                                       bool strict_match);
  56 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  57 static void rlb_src_unlink(struct bonding *bond, u32 index);
  58 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  59                          u32 ip_dst_hash);
  60
  61 static 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
  74 static 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
  87 static 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
  93 static 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
 116 static 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 */
 125 static 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 */
 149 static 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
 161 static 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
 167 static 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
 191 static 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
 227 static 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  */
 248 static 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
 272 static 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         }
 301 out:
 302         return RX_HANDLER_ANOTHER;
 303 }
 304
 305 /* Caller must hold rcu_read_lock() */
 306 static 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 */
 339 static 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  */
 357 static 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  */
 381 static 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
 424 static 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 */
 460 static 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 */
 488 static 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 */
 520 static 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
 553 static 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  */
 653 static 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 locally
 664          * (e.g.,arrive via a bridge).
 665          */
 666         if (!bond_slave_has_mac_rx(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_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
 712 static 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 */
 744 static 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 }
 752 static 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
 759 static 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
 766 static 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 */
 781 static 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
 804 static 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  */
 818 static 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  */
 834 static 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
 855 static 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
 883 static 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
 896 static 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
 919 static 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
 952 struct alb_walk_data {
 953         struct bonding *bond;
 954         struct slave *slave;
 955         const u8 *mac_addr;
 956         bool strict_match;
 957 };
 958
 959 static 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                         BUG();
 989                 alb_send_lp_vid(slave, upper->dev_addr,
 990                                 tags[0].vlan_proto, tags[0].vlan_id);
 991                 kfree(tags);
 992         }
 993
 994         return 0;
 995 }
 996
 997 static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
 998                                       bool strict_match)
 999 {
1000         struct bonding *bond = bond_get_bond_by_slave(slave);
1001         struct netdev_nested_priv priv;
1002         struct alb_walk_data data = {
1003                 .strict_match = strict_match,
1004                 .mac_addr = mac_addr,
1005                 .slave = slave,
1006                 .bond = bond,
1007         };
1008
1009         priv.data = (void *)&data;
1010         /* send untagged */
1011         alb_send_lp_vid(slave, mac_addr, 0, 0);
1012
1013         /* loop through all devices and see if we need to send a packet
1014          * for that device.
1015          */
1016         rcu_read_lock();
1017         netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &priv);
1018         rcu_read_unlock();
1019 }
1020
1021 static int alb_set_slave_mac_addr(struct slave *slave, const u8 addr[],
1022                                   unsigned int len)
1023 {
1024         struct net_device *dev = slave->dev;
1025         struct sockaddr_storage ss;
1026
1027         if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1028                 __dev_addr_set(dev, addr, len);
1029                 return 0;
1030         }
1031
1032         /* for rlb each slave must have a unique hw mac addresses so that
1033          * each slave will receive packets destined to a different mac
1034          */
1035         memcpy(ss.__data, addr, len);
1036         ss.ss_family = dev->type;
1037         if (dev_set_mac_address(dev, (struct sockaddr *)&ss, NULL)) {
1038                 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");
1039                 return -EOPNOTSUPP;
1040         }
1041         return 0;
1042 }
1043
1044 /* Swap MAC addresses between two slaves.
1045  *
1046  * Called with RTNL held, and no other locks.
1047  */
1048 static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1049 {
1050         u8 tmp_mac_addr[MAX_ADDR_LEN];
1051
1052         bond_hw_addr_copy(tmp_mac_addr, slave1->dev->dev_addr,
1053                           slave1->dev->addr_len);
1054         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr,
1055                                slave2->dev->addr_len);
1056         alb_set_slave_mac_addr(slave2, tmp_mac_addr,
1057                                slave1->dev->addr_len);
1058
1059 }
1060
1061 /* Send learning packets after MAC address swap.
1062  *
1063  * Called with RTNL and no other locks
1064  */
1065 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1066                                 struct slave *slave2)
1067 {
1068         int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1069         struct slave *disabled_slave = NULL;
1070
1071         ASSERT_RTNL();
1072
1073         /* fasten the change in the switch */
1074         if (bond_slave_can_tx(slave1)) {
1075                 alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1076                 if (bond->alb_info.rlb_enabled) {
1077                         /* inform the clients that the mac address
1078                          * has changed
1079                          */
1080                         rlb_req_update_slave_clients(bond, slave1);
1081                 }
1082         } else {
1083                 disabled_slave = slave1;
1084         }
1085
1086         if (bond_slave_can_tx(slave2)) {
1087                 alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1088                 if (bond->alb_info.rlb_enabled) {
1089                         /* inform the clients that the mac address
1090                          * has changed
1091                          */
1092                         rlb_req_update_slave_clients(bond, slave2);
1093                 }
1094         } else {
1095                 disabled_slave = slave2;
1096         }
1097
1098         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1099                 /* A disabled slave was assigned an active mac addr */
1100                 rlb_teach_disabled_mac_on_primary(bond,
1101                                                   disabled_slave->dev->dev_addr);
1102         }
1103 }
1104
1105 /**
1106  * alb_change_hw_addr_on_detach
1107  * @bond: bonding we're working on
1108  * @slave: the slave that was just detached
1109  *
1110  * We assume that @slave was already detached from the slave list.
1111  *
1112  * If @slave's permanent hw address is different both from its current
1113  * address and from @bond's address, then somewhere in the bond there's
1114  * a slave that has @slave's permanet address as its current address.
1115  * We'll make sure that slave no longer uses @slave's permanent address.
1116  *
1117  * Caller must hold RTNL and no other locks
1118  */
1119 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1120 {
1121         int perm_curr_diff;
1122         int perm_bond_diff;
1123         struct slave *found_slave;
1124
1125         perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1126                                                   slave->dev->dev_addr);
1127         perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1128                                                   bond->dev->dev_addr);
1129
1130         if (perm_curr_diff && perm_bond_diff) {
1131                 found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1132
1133                 if (found_slave) {
1134                         alb_swap_mac_addr(slave, found_slave);
1135                         alb_fasten_mac_swap(bond, slave, found_slave);
1136                 }
1137         }
1138 }
1139
1140 /**
1141  * alb_handle_addr_collision_on_attach
1142  * @bond: bonding we're working on
1143  * @slave: the slave that was just attached
1144  *
1145  * checks uniqueness of slave's mac address and handles the case the
1146  * new slave uses the bonds mac address.
1147  *
1148  * If the permanent hw address of @slave is @bond's hw address, we need to
1149  * find a different hw address to give @slave, that isn't in use by any other
1150  * slave in the bond. This address must be, of course, one of the permanent
1151  * addresses of the other slaves.
1152  *
1153  * We go over the slave list, and for each slave there we compare its
1154  * permanent hw address with the current address of all the other slaves.
1155  * If no match was found, then we've found a slave with a permanent address
1156  * that isn't used by any other slave in the bond, so we can assign it to
1157  * @slave.
1158  *
1159  * assumption: this function is called before @slave is attached to the
1160  *             bond slave list.
1161  */
1162 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1163 {
1164         struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1165         struct slave *tmp_slave1, *free_mac_slave = NULL;
1166         struct list_head *iter;
1167
1168         if (!bond_has_slaves(bond)) {
1169                 /* this is the first slave */
1170                 return 0;
1171         }
1172
1173         /* if slave's mac address differs from bond's mac address
1174          * check uniqueness of slave's mac address against the other
1175          * slaves in the bond.
1176          */
1177         if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1178                 if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1179                         return 0;
1180
1181                 /* Try setting slave mac to bond address and fall-through
1182                  * to code handling that situation below...
1183                  */
1184                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1185                                        bond->dev->addr_len);
1186         }
1187
1188         /* The slave's address is equal to the address of the bond.
1189          * Search for a spare address in the bond for this slave.
1190          */
1191         bond_for_each_slave(bond, tmp_slave1, iter) {
1192                 if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1193                         /* no slave has tmp_slave1's perm addr
1194                          * as its curr addr
1195                          */
1196                         free_mac_slave = tmp_slave1;
1197                         break;
1198                 }
1199
1200                 if (!has_bond_addr) {
1201                         if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1202                                                     bond->dev->dev_addr)) {
1203
1204                                 has_bond_addr = tmp_slave1;
1205                         }
1206                 }
1207         }
1208
1209         if (free_mac_slave) {
1210                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1211                                        free_mac_slave->dev->addr_len);
1212
1213                 slave_warn(bond->dev, slave->dev, "the slave hw address is in use by the bond; giving it the hw address of %s\n",
1214                            free_mac_slave->dev->name);
1215
1216         } else if (has_bond_addr) {
1217                 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");
1218                 return -EFAULT;
1219         }
1220
1221         return 0;
1222 }
1223
1224 /**
1225  * alb_set_mac_address
1226  * @bond: bonding we're working on
1227  * @addr: MAC address to set
1228  *
1229  * In TLB mode all slaves are configured to the bond's hw address, but set
1230  * their dev_addr field to different addresses (based on their permanent hw
1231  * addresses).
1232  *
1233  * For each slave, this function sets the interface to the new address and then
1234  * changes its dev_addr field to its previous value.
1235  *
1236  * Unwinding assumes bond's mac address has not yet changed.
1237  */
1238 static int alb_set_mac_address(struct bonding *bond, void *addr)
1239 {
1240         struct slave *slave, *rollback_slave;
1241         struct list_head *iter;
1242         struct sockaddr_storage ss;
1243         char tmp_addr[MAX_ADDR_LEN];
1244         int res;
1245
1246         if (bond->alb_info.rlb_enabled)
1247                 return 0;
1248
1249         bond_for_each_slave(bond, slave, iter) {
1250                 /* save net_device's current hw address */
1251                 bond_hw_addr_copy(tmp_addr, slave->dev->dev_addr,
1252                                   slave->dev->addr_len);
1253
1254                 res = dev_set_mac_address(slave->dev, addr, NULL);
1255
1256                 /* restore net_device's hw address */
1257                 dev_addr_set(slave->dev, tmp_addr);
1258
1259                 if (res)
1260                         goto unwind;
1261         }
1262
1263         return 0;
1264
1265 unwind:
1266         memcpy(ss.__data, bond->dev->dev_addr, bond->dev->addr_len);
1267         ss.ss_family = bond->dev->type;
1268
1269         /* unwind from head to the slave that failed */
1270         bond_for_each_slave(bond, rollback_slave, iter) {
1271                 if (rollback_slave == slave)
1272                         break;
1273                 bond_hw_addr_copy(tmp_addr, rollback_slave->dev->dev_addr,
1274                                   rollback_slave->dev->addr_len);
1275                 dev_set_mac_address(rollback_slave->dev,
1276                                     (struct sockaddr *)&ss, NULL);
1277                 dev_addr_set(rollback_slave->dev, tmp_addr);
1278         }
1279
1280         return res;
1281 }
1282
1283 /* determine if the packet is NA or NS */
1284 static bool alb_determine_nd(struct sk_buff *skb, struct bonding *bond)
1285 {
1286         struct ipv6hdr *ip6hdr;
1287         struct icmp6hdr *hdr;
1288
1289         if (!pskb_network_may_pull(skb, sizeof(*ip6hdr)))
1290                 return true;
1291
1292         ip6hdr = ipv6_hdr(skb);
1293         if (ip6hdr->nexthdr != IPPROTO_ICMPV6)
1294                 return false;
1295
1296         if (!pskb_network_may_pull(skb, sizeof(*ip6hdr) + sizeof(*hdr)))
1297                 return true;
1298
1299         hdr = icmp6_hdr(skb);
1300         return hdr->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT ||
1301                 hdr->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION;
1302 }
1303
1304 /************************ exported alb functions ************************/
1305
1306 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1307 {
1308         int res;
1309
1310         res = tlb_initialize(bond);
1311         if (res)
1312                 return res;
1313
1314         if (rlb_enabled) {
1315                 res = rlb_initialize(bond);
1316                 if (res) {
1317                         tlb_deinitialize(bond);
1318                         return res;
1319                 }
1320                 bond->alb_info.rlb_enabled = 1;
1321         } else {
1322                 bond->alb_info.rlb_enabled = 0;
1323         }
1324
1325         return 0;
1326 }
1327
1328 void bond_alb_deinitialize(struct bonding *bond)
1329 {
1330         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1331
1332         tlb_deinitialize(bond);
1333
1334         if (bond_info->rlb_enabled)
1335                 rlb_deinitialize(bond);
1336 }
1337
1338 static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1339                                     struct slave *tx_slave)
1340 {
1341         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1342         struct ethhdr *eth_data = eth_hdr(skb);
1343
1344         if (!tx_slave) {
1345                 /* unbalanced or unassigned, send through primary */
1346                 tx_slave = rcu_dereference(bond->curr_active_slave);
1347                 if (bond->params.tlb_dynamic_lb)
1348                         bond_info->unbalanced_load += skb->len;
1349         }
1350
1351         if (tx_slave && bond_slave_can_tx(tx_slave)) {
1352                 if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1353                         ether_addr_copy(eth_data->h_source,
1354                                         tx_slave->dev->dev_addr);
1355                 }
1356
1357                 return bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1358         }
1359
1360         if (tx_slave && bond->params.tlb_dynamic_lb) {
1361                 spin_lock(&bond->mode_lock);
1362                 __tlb_clear_slave(bond, tx_slave, 0);
1363                 spin_unlock(&bond->mode_lock);
1364         }
1365
1366         /* no suitable interface, frame not sent */
1367         return bond_tx_drop(bond->dev, skb);
1368 }
1369
1370 struct slave *bond_xmit_tlb_slave_get(struct bonding *bond,
1371                                       struct sk_buff *skb)
1372 {
1373         struct slave *tx_slave = NULL;
1374         struct ethhdr *eth_data;
1375         u32 hash_index;
1376
1377         skb_reset_mac_header(skb);
1378         eth_data = eth_hdr(skb);
1379
1380         /* Do not TX balance any multicast or broadcast */
1381         if (!is_multicast_ether_addr(eth_data->h_dest)) {
1382                 switch (skb->protocol) {
1383                 case htons(ETH_P_IPV6):
1384                         if (alb_determine_nd(skb, bond))
1385                                 break;
1386                         fallthrough;
1387                 case htons(ETH_P_IP):
1388                         hash_index = bond_xmit_hash(bond, skb);
1389                         if (bond->params.tlb_dynamic_lb) {
1390                                 tx_slave = tlb_choose_channel(bond,
1391                                                               hash_index & 0xFF,
1392                                                               skb->len);
1393                         } else {
1394                                 struct bond_up_slave *slaves;
1395                                 unsigned int count;
1396
1397                                 slaves = rcu_dereference(bond->usable_slaves);
1398                                 count = slaves ? READ_ONCE(slaves->count) : 0;
1399                                 if (likely(count))
1400                                         tx_slave = slaves->arr[hash_index %
1401                                                                count];
1402                         }
1403                         break;
1404                 }
1405         }
1406         return tx_slave;
1407 }
1408
1409 netdev_tx_t bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1410 {
1411         struct bonding *bond = netdev_priv(bond_dev);
1412         struct slave *tx_slave;
1413
1414         tx_slave = bond_xmit_tlb_slave_get(bond, skb);
1415         return bond_do_alb_xmit(skb, bond, tx_slave);
1416 }
1417
1418 struct slave *bond_xmit_alb_slave_get(struct bonding *bond,
1419                                       struct sk_buff *skb)
1420 {
1421         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1422         static const __be32 ip_bcast = htonl(0xffffffff);
1423         struct slave *tx_slave = NULL;
1424         const u8 *hash_start = NULL;
1425         bool do_tx_balance = true;
1426         struct ethhdr *eth_data;
1427         u32 hash_index = 0;
1428         int hash_size = 0;
1429
1430         skb_reset_mac_header(skb);
1431         eth_data = eth_hdr(skb);
1432
1433         switch (ntohs(skb->protocol)) {
1434         case ETH_P_IP: {
1435                 const struct iphdr *iph;
1436
1437                 if (is_broadcast_ether_addr(eth_data->h_dest) ||
1438                     !pskb_network_may_pull(skb, sizeof(*iph))) {
1439                         do_tx_balance = false;
1440                         break;
1441                 }
1442                 iph = ip_hdr(skb);
1443                 if (iph->daddr == ip_bcast || iph->protocol == IPPROTO_IGMP) {
1444                         do_tx_balance = false;
1445                         break;
1446                 }
1447                 hash_start = (char *)&(iph->daddr);
1448                 hash_size = sizeof(iph->daddr);
1449                 break;
1450         }
1451         case ETH_P_IPV6: {
1452                 const struct ipv6hdr *ip6hdr;
1453
1454                 /* IPv6 doesn't really use broadcast mac address, but leave
1455                  * that here just in case.
1456                  */
1457                 if (is_broadcast_ether_addr(eth_data->h_dest)) {
1458                         do_tx_balance = false;
1459                         break;
1460                 }
1461
1462                 /* IPv6 uses all-nodes multicast as an equivalent to
1463                  * broadcasts in IPv4.
1464                  */
1465                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1466                         do_tx_balance = false;
1467                         break;
1468                 }
1469
1470                 if (alb_determine_nd(skb, bond)) {
1471                         do_tx_balance = false;
1472                         break;
1473                 }
1474
1475                 /* The IPv6 header is pulled by alb_determine_nd */
1476                 /* Additionally, DAD probes should not be tx-balanced as that
1477                  * will lead to false positives for duplicate addresses and
1478                  * prevent address configuration from working.
1479                  */
1480                 ip6hdr = ipv6_hdr(skb);
1481                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1482                         do_tx_balance = false;
1483                         break;
1484                 }
1485
1486                 hash_start = (char *)&ip6hdr->daddr;
1487                 hash_size = sizeof(ip6hdr->daddr);
1488                 break;
1489         }
1490         case ETH_P_ARP:
1491                 do_tx_balance = false;
1492                 if (bond_info->rlb_enabled)
1493                         tx_slave = rlb_arp_xmit(skb, bond);
1494                 break;
1495         default:
1496                 do_tx_balance = false;
1497                 break;
1498         }
1499
1500         if (do_tx_balance) {
1501                 if (bond->params.tlb_dynamic_lb) {
1502                         hash_index = _simple_hash(hash_start, hash_size);
1503                         tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1504                 } else {
1505                         /*
1506                          * do_tx_balance means we are free to select the tx_slave
1507                          * So we do exactly what tlb would do for hash selection
1508                          */
1509
1510                         struct bond_up_slave *slaves;
1511                         unsigned int count;
1512
1513                         slaves = rcu_dereference(bond->usable_slaves);
1514                         count = slaves ? READ_ONCE(slaves->count) : 0;
1515                         if (likely(count))
1516                                 tx_slave = slaves->arr[bond_xmit_hash(bond, skb) %
1517                                                        count];
1518                 }
1519         }
1520         return tx_slave;
1521 }
1522
1523 netdev_tx_t bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1524 {
1525         struct bonding *bond = netdev_priv(bond_dev);
1526         struct slave *tx_slave = NULL;
1527
1528         tx_slave = bond_xmit_alb_slave_get(bond, skb);
1529         return bond_do_alb_xmit(skb, bond, tx_slave);
1530 }
1531
1532 void bond_alb_monitor(struct work_struct *work)
1533 {
1534         struct bonding *bond = container_of(work, struct bonding,
1535                                             alb_work.work);
1536         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1537         struct list_head *iter;
1538         struct slave *slave;
1539
1540         if (!bond_has_slaves(bond)) {
1541                 atomic_set(&bond_info->tx_rebalance_counter, 0);
1542                 bond_info->lp_counter = 0;
1543                 goto re_arm;
1544         }
1545
1546         rcu_read_lock();
1547
1548         atomic_inc(&bond_info->tx_rebalance_counter);
1549         bond_info->lp_counter++;
1550
1551         /* send learning packets */
1552         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1553                 bool strict_match;
1554
1555                 bond_for_each_slave_rcu(bond, slave, iter) {
1556                         /* If updating current_active, use all currently
1557                          * user mac addresses (!strict_match).  Otherwise, only
1558                          * use mac of the slave device.
1559                          * In RLB mode, we always use strict matches.
1560                          */
1561                         strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1562                                         bond_info->rlb_enabled);
1563                         alb_send_learning_packets(slave, slave->dev->dev_addr,
1564                                                   strict_match);
1565                 }
1566                 bond_info->lp_counter = 0;
1567         }
1568
1569         /* rebalance tx traffic */
1570         if (atomic_read(&bond_info->tx_rebalance_counter) >= BOND_TLB_REBALANCE_TICKS) {
1571                 bond_for_each_slave_rcu(bond, slave, iter) {
1572                         tlb_clear_slave(bond, slave, 1);
1573                         if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1574                                 SLAVE_TLB_INFO(slave).load =
1575                                         bond_info->unbalanced_load /
1576                                                 BOND_TLB_REBALANCE_INTERVAL;
1577                                 bond_info->unbalanced_load = 0;
1578                         }
1579                 }
1580                 atomic_set(&bond_info->tx_rebalance_counter, 0);
1581         }
1582
1583         if (bond_info->rlb_enabled) {
1584                 if (bond_info->primary_is_promisc &&
1585                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1586
1587                         /* dev_set_promiscuity requires rtnl and
1588                          * nothing else.  Avoid race with bond_close.
1589                          */
1590                         rcu_read_unlock();
1591                         if (!rtnl_trylock())
1592                                 goto re_arm;
1593
1594                         bond_info->rlb_promisc_timeout_counter = 0;
1595
1596                         /* If the primary was set to promiscuous mode
1597                          * because a slave was disabled then
1598                          * it can now leave promiscuous mode.
1599                          */
1600                         dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1601                                             -1);
1602                         bond_info->primary_is_promisc = 0;
1603
1604                         rtnl_unlock();
1605                         rcu_read_lock();
1606                 }
1607
1608                 if (bond_info->rlb_rebalance) {
1609                         bond_info->rlb_rebalance = 0;
1610                         rlb_rebalance(bond);
1611                 }
1612
1613                 /* check if clients need updating */
1614                 if (bond_info->rx_ntt) {
1615                         if (bond_info->rlb_update_delay_counter) {
1616                                 --bond_info->rlb_update_delay_counter;
1617                         } else {
1618                                 rlb_update_rx_clients(bond);
1619                                 if (bond_info->rlb_update_retry_counter)
1620                                         --bond_info->rlb_update_retry_counter;
1621                                 else
1622                                         bond_info->rx_ntt = 0;
1623                         }
1624                 }
1625         }
1626         rcu_read_unlock();
1627 re_arm:
1628         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1629 }
1630
1631 /* assumption: called before the slave is attached to the bond
1632  * and not locked by the bond lock
1633  */
1634 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1635 {
1636         int res;
1637
1638         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1639                                      slave->dev->addr_len);
1640         if (res)
1641                 return res;
1642
1643         res = alb_handle_addr_collision_on_attach(bond, slave);
1644         if (res)
1645                 return res;
1646
1647         tlb_init_slave(slave);
1648
1649         /* order a rebalance ASAP */
1650         atomic_set(&bond->alb_info.tx_rebalance_counter,
1651                    BOND_TLB_REBALANCE_TICKS);
1652
1653         if (bond->alb_info.rlb_enabled)
1654                 bond->alb_info.rlb_rebalance = 1;
1655
1656         return 0;
1657 }
1658
1659 /* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1660  * if necessary.
1661  *
1662  * Caller must hold RTNL and no other locks
1663  */
1664 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1665 {
1666         if (bond_has_slaves(bond))
1667                 alb_change_hw_addr_on_detach(bond, slave);
1668
1669         tlb_clear_slave(bond, slave, 0);
1670
1671         if (bond->alb_info.rlb_enabled) {
1672                 bond->alb_info.rx_slave = NULL;
1673                 rlb_clear_slave(bond, slave);
1674         }
1675
1676 }
1677
1678 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1679 {
1680         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1681
1682         if (link == BOND_LINK_DOWN) {
1683                 tlb_clear_slave(bond, slave, 0);
1684                 if (bond->alb_info.rlb_enabled)
1685                         rlb_clear_slave(bond, slave);
1686         } else if (link == BOND_LINK_UP) {
1687                 /* order a rebalance ASAP */
1688                 atomic_set(&bond_info->tx_rebalance_counter,
1689                            BOND_TLB_REBALANCE_TICKS);
1690                 if (bond->alb_info.rlb_enabled) {
1691                         bond->alb_info.rlb_rebalance = 1;
1692                         /* If the updelay module parameter is smaller than the
1693                          * forwarding delay of the switch the rebalance will
1694                          * not work because the rebalance arp replies will
1695                          * not be forwarded to the clients..
1696                          */
1697                 }
1698         }
1699
1700         if (bond_is_nondyn_tlb(bond)) {
1701                 if (bond_update_slave_arr(bond, NULL))
1702                         pr_err("Failed to build slave-array for TLB mode.\n");
1703         }
1704 }
1705
1706 /**
1707  * bond_alb_handle_active_change - assign new curr_active_slave
1708  * @bond: our bonding struct
1709  * @new_slave: new slave to assign
1710  *
1711  * Set the bond->curr_active_slave to @new_slave and handle
1712  * mac address swapping and promiscuity changes as needed.
1713  *
1714  * Caller must hold RTNL
1715  */
1716 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1717 {
1718         struct slave *swap_slave;
1719         struct slave *curr_active;
1720
1721         curr_active = rtnl_dereference(bond->curr_active_slave);
1722         if (curr_active == new_slave)
1723                 return;
1724
1725         if (curr_active && bond->alb_info.primary_is_promisc) {
1726                 dev_set_promiscuity(curr_active->dev, -1);
1727                 bond->alb_info.primary_is_promisc = 0;
1728                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1729         }
1730
1731         swap_slave = curr_active;
1732         rcu_assign_pointer(bond->curr_active_slave, new_slave);
1733
1734         if (!new_slave || !bond_has_slaves(bond))
1735                 return;
1736
1737         /* set the new curr_active_slave to the bonds mac address
1738          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1739          */
1740         if (!swap_slave)
1741                 swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1742
1743         /* Arrange for swap_slave and new_slave to temporarily be
1744          * ignored so we can mess with their MAC addresses without
1745          * fear of interference from transmit activity.
1746          */
1747         if (swap_slave)
1748                 tlb_clear_slave(bond, swap_slave, 1);
1749         tlb_clear_slave(bond, new_slave, 1);
1750
1751         /* in TLB mode, the slave might flip down/up with the old dev_addr,
1752          * and thus filter bond->dev_addr's packets, so force bond's mac
1753          */
1754         if (BOND_MODE(bond) == BOND_MODE_TLB) {
1755                 struct sockaddr_storage ss;
1756                 u8 tmp_addr[MAX_ADDR_LEN];
1757
1758                 bond_hw_addr_copy(tmp_addr, new_slave->dev->dev_addr,
1759                                   new_slave->dev->addr_len);
1760
1761                 bond_hw_addr_copy(ss.__data, bond->dev->dev_addr,
1762                                   bond->dev->addr_len);
1763                 ss.ss_family = bond->dev->type;
1764                 /* we don't care if it can't change its mac, best effort */
1765                 dev_set_mac_address(new_slave->dev, (struct sockaddr *)&ss,
1766                                     NULL);
1767
1768                 dev_addr_set(new_slave->dev, tmp_addr);
1769         }
1770
1771         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1772         if (swap_slave) {
1773                 /* swap mac address */
1774                 alb_swap_mac_addr(swap_slave, new_slave);
1775                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1776         } else {
1777                 /* set the new_slave to the bond mac address */
1778                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1779                                        bond->dev->addr_len);
1780                 alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1781                                           false);
1782         }
1783 }
1784
1785 /* Called with RTNL */
1786 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1787 {
1788         struct bonding *bond = netdev_priv(bond_dev);
1789         struct sockaddr_storage *ss = addr;
1790         struct slave *curr_active;
1791         struct slave *swap_slave;
1792         int res;
1793
1794         if (!is_valid_ether_addr(ss->__data))
1795                 return -EADDRNOTAVAIL;
1796
1797         res = alb_set_mac_address(bond, addr);
1798         if (res)
1799                 return res;
1800
1801         dev_addr_set(bond_dev, ss->__data);
1802
1803         /* If there is no curr_active_slave there is nothing else to do.
1804          * Otherwise we'll need to pass the new address to it and handle
1805          * duplications.
1806          */
1807         curr_active = rtnl_dereference(bond->curr_active_slave);
1808         if (!curr_active)
1809                 return 0;
1810
1811         swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1812
1813         if (swap_slave) {
1814                 alb_swap_mac_addr(swap_slave, curr_active);
1815                 alb_fasten_mac_swap(bond, swap_slave, curr_active);
1816         } else {
1817                 alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr,
1818                                        bond_dev->addr_len);
1819
1820                 alb_send_learning_packets(curr_active,
1821                                           bond_dev->dev_addr, false);
1822                 if (bond->alb_info.rlb_enabled) {
1823                         /* inform clients mac address has changed */
1824                         rlb_req_update_slave_clients(bond, curr_active);
1825                 }
1826         }
1827
1828         return 0;
1829 }
1830
1831 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1832 {
1833         if (bond->alb_info.rlb_enabled)
1834                 rlb_clear_vlan(bond, vlan_id);
1835 }
1836