drivers/net/bonding/bond_alb.c

   1 /*
   2  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License as published by the
   6  * Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, see <http://www.gnu.org/licenses/>.
  16  *
  17  * The full GNU General Public License is included in this distribution in the
  18  * file called LICENSE.
  19  *
  20  */
  21
  22 #include <linux/skbuff.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/etherdevice.h>
  25 #include <linux/pkt_sched.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/slab.h>
  28 #include <linux/timer.h>
  29 #include <linux/ip.h>
  30 #include <linux/ipv6.h>
  31 #include <linux/if_arp.h>
  32 #include <linux/if_ether.h>
  33 #include <linux/if_bonding.h>
  34 #include <linux/if_vlan.h>
  35 #include <linux/in.h>
  36 #include <net/ipx.h>
  37 #include <net/arp.h>
  38 #include <net/ipv6.h>
  39 #include <asm/byteorder.h>
  40 #include <net/bonding.h>
  41 #include <net/bond_alb.h>
  42
  43
  44
  45 static const u8 mac_bcast[ETH_ALEN + 2] __long_aligned = {
  46         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  47 };
  48 static const u8 mac_v6_allmcast[ETH_ALEN + 2] __long_aligned = {
  49         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  50 };
  51 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  52
  53 #pragma pack(1)
  54 struct learning_pkt {
  55         u8 mac_dst[ETH_ALEN];
  56         u8 mac_src[ETH_ALEN];
  57         __be16 type;
  58         u8 padding[ETH_ZLEN - ETH_HLEN];
  59 };
  60
  61 struct arp_pkt {
  62         __be16  hw_addr_space;
  63         __be16  prot_addr_space;
  64         u8      hw_addr_len;
  65         u8      prot_addr_len;
  66         __be16  op_code;
  67         u8      mac_src[ETH_ALEN];      /* sender hardware address */
  68         __be32  ip_src;                 /* sender IP address */
  69         u8      mac_dst[ETH_ALEN];      /* target hardware address */
  70         __be32  ip_dst;                 /* target IP address */
  71 };
  72 #pragma pack()
  73
  74 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
  75 {
  76         return (struct arp_pkt *)skb_network_header(skb);
  77 }
  78
  79 /* Forward declaration */
  80 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
  81                                       bool strict_match);
  82 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  83 static void rlb_src_unlink(struct bonding *bond, u32 index);
  84 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  85                          u32 ip_dst_hash);
  86
  87 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  88 {
  89         int i;
  90         u8 hash = 0;
  91
  92         for (i = 0; i < hash_size; i++)
  93                 hash ^= hash_start[i];
  94
  95         return hash;
  96 }
  97
  98 /*********************** tlb specific functions ***************************/
  99
 100 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 101 {
 102         if (save_load) {
 103                 entry->load_history = 1 + entry->tx_bytes /
 104                                       BOND_TLB_REBALANCE_INTERVAL;
 105                 entry->tx_bytes = 0;
 106         }
 107
 108         entry->tx_slave = NULL;
 109         entry->next = TLB_NULL_INDEX;
 110         entry->prev = TLB_NULL_INDEX;
 111 }
 112
 113 static inline void tlb_init_slave(struct slave *slave)
 114 {
 115         SLAVE_TLB_INFO(slave).load = 0;
 116         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 117 }
 118
 119 static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
 120                          int save_load)
 121 {
 122         struct tlb_client_info *tx_hash_table;
 123         u32 index;
 124
 125         /* clear slave from tx_hashtbl */
 126         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 127
 128         /* skip this if we've already freed the tx hash table */
 129         if (tx_hash_table) {
 130                 index = SLAVE_TLB_INFO(slave).head;
 131                 while (index != TLB_NULL_INDEX) {
 132                         u32 next_index = tx_hash_table[index].next;
 133                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 134                         index = next_index;
 135                 }
 136         }
 137
 138         tlb_init_slave(slave);
 139 }
 140
 141 static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 142                          int save_load)
 143 {
 144         spin_lock_bh(&bond->mode_lock);
 145         __tlb_clear_slave(bond, slave, save_load);
 146         spin_unlock_bh(&bond->mode_lock);
 147 }
 148
 149 /* Must be called before starting the monitor timer */
 150 static int tlb_initialize(struct bonding *bond)
 151 {
 152         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 153         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 154         struct tlb_client_info *new_hashtbl;
 155         int i;
 156
 157         new_hashtbl = kzalloc(size, GFP_KERNEL);
 158         if (!new_hashtbl)
 159                 return -ENOMEM;
 160
 161         spin_lock_bh(&bond->mode_lock);
 162
 163         bond_info->tx_hashtbl = new_hashtbl;
 164
 165         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
 166                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 167
 168         spin_unlock_bh(&bond->mode_lock);
 169
 170         return 0;
 171 }
 172
 173 /* Must be called only after all slaves have been released */
 174 static void tlb_deinitialize(struct bonding *bond)
 175 {
 176         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 177
 178         spin_lock_bh(&bond->mode_lock);
 179
 180         kfree(bond_info->tx_hashtbl);
 181         bond_info->tx_hashtbl = NULL;
 182
 183         spin_unlock_bh(&bond->mode_lock);
 184 }
 185
 186 static long long compute_gap(struct slave *slave)
 187 {
 188         return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 189                (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 190 }
 191
 192 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 193 {
 194         struct slave *slave, *least_loaded;
 195         struct list_head *iter;
 196         long long max_gap;
 197
 198         least_loaded = NULL;
 199         max_gap = LLONG_MIN;
 200
 201         /* Find the slave with the largest gap */
 202         bond_for_each_slave_rcu(bond, slave, iter) {
 203                 if (bond_slave_can_tx(slave)) {
 204                         long long gap = compute_gap(slave);
 205
 206                         if (max_gap < gap) {
 207                                 least_loaded = slave;
 208                                 max_gap = gap;
 209                         }
 210                 }
 211         }
 212
 213         return least_loaded;
 214 }
 215
 216 static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 217                                                 u32 skb_len)
 218 {
 219         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 220         struct tlb_client_info *hash_table;
 221         struct slave *assigned_slave;
 222
 223         hash_table = bond_info->tx_hashtbl;
 224         assigned_slave = hash_table[hash_index].tx_slave;
 225         if (!assigned_slave) {
 226                 assigned_slave = tlb_get_least_loaded_slave(bond);
 227
 228                 if (assigned_slave) {
 229                         struct tlb_slave_info *slave_info =
 230                                 &(SLAVE_TLB_INFO(assigned_slave));
 231                         u32 next_index = slave_info->head;
 232
 233                         hash_table[hash_index].tx_slave = assigned_slave;
 234                         hash_table[hash_index].next = next_index;
 235                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 236
 237                         if (next_index != TLB_NULL_INDEX)
 238                                 hash_table[next_index].prev = hash_index;
 239
 240                         slave_info->head = hash_index;
 241                         slave_info->load +=
 242                                 hash_table[hash_index].load_history;
 243                 }
 244         }
 245
 246         if (assigned_slave)
 247                 hash_table[hash_index].tx_bytes += skb_len;
 248
 249         return assigned_slave;
 250 }
 251
 252 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 253                                         u32 skb_len)
 254 {
 255         struct slave *tx_slave;
 256
 257         /* We don't need to disable softirq here, becase
 258          * tlb_choose_channel() is only called by bond_alb_xmit()
 259          * which already has softirq disabled.
 260          */
 261         spin_lock(&bond->mode_lock);
 262         tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 263         spin_unlock(&bond->mode_lock);
 264
 265         return tx_slave;
 266 }
 267
 268 /*********************** rlb specific functions ***************************/
 269
 270 /* when an ARP REPLY is received from a client update its info
 271  * in the rx_hashtbl
 272  */
 273 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 274 {
 275         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 276         struct rlb_client_info *client_info;
 277         u32 hash_index;
 278
 279         spin_lock_bh(&bond->mode_lock);
 280
 281         hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 282         client_info = &(bond_info->rx_hashtbl[hash_index]);
 283
 284         if ((client_info->assigned) &&
 285             (client_info->ip_src == arp->ip_dst) &&
 286             (client_info->ip_dst == arp->ip_src) &&
 287             (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
 288                 /* update the clients MAC address */
 289                 ether_addr_copy(client_info->mac_dst, arp->mac_src);
 290                 client_info->ntt = 1;
 291                 bond_info->rx_ntt = 1;
 292         }
 293
 294         spin_unlock_bh(&bond->mode_lock);
 295 }
 296
 297 static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
 298                         struct slave *slave)
 299 {
 300         struct arp_pkt *arp, _arp;
 301
 302         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 303                 goto out;
 304
 305         arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
 306         if (!arp)
 307                 goto out;
 308
 309         /* We received an ARP from arp->ip_src.
 310          * We might have used this IP address previously (on the bonding host
 311          * itself or on a system that is bridged together with the bond).
 312          * However, if arp->mac_src is different than what is stored in
 313          * rx_hashtbl, some other host is now using the IP and we must prevent
 314          * sending out client updates with this IP address and the old MAC
 315          * address.
 316          * Clean up all hash table entries that have this address as ip_src but
 317          * have a different mac_src.
 318          */
 319         rlb_purge_src_ip(bond, arp);
 320
 321         if (arp->op_code == htons(ARPOP_REPLY)) {
 322                 /* update rx hash table for this ARP */
 323                 rlb_update_entry_from_arp(bond, arp);
 324                 netdev_dbg(bond->dev, "Server received an ARP Reply from client\n");
 325         }
 326 out:
 327         return RX_HANDLER_ANOTHER;
 328 }
 329
 330 /* Caller must hold rcu_read_lock() */
 331 static struct slave *__rlb_next_rx_slave(struct bonding *bond)
 332 {
 333         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 334         struct slave *before = NULL, *rx_slave = NULL, *slave;
 335         struct list_head *iter;
 336         bool found = false;
 337
 338         bond_for_each_slave_rcu(bond, slave, iter) {
 339                 if (!bond_slave_can_tx(slave))
 340                         continue;
 341                 if (!found) {
 342                         if (!before || before->speed < slave->speed)
 343                                 before = slave;
 344                 } else {
 345                         if (!rx_slave || rx_slave->speed < slave->speed)
 346                                 rx_slave = slave;
 347                 }
 348                 if (slave == bond_info->rx_slave)
 349                         found = true;
 350         }
 351         /* we didn't find anything after the current or we have something
 352          * better before and up to the current slave
 353          */
 354         if (!rx_slave || (before && rx_slave->speed < before->speed))
 355                 rx_slave = before;
 356
 357         if (rx_slave)
 358                 bond_info->rx_slave = rx_slave;
 359
 360         return rx_slave;
 361 }
 362
 363 /* Caller must hold RTNL, rcu_read_lock is obtained only to silence checkers */
 364 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 365 {
 366         struct slave *rx_slave;
 367
 368         ASSERT_RTNL();
 369
 370         rcu_read_lock();
 371         rx_slave = __rlb_next_rx_slave(bond);
 372         rcu_read_unlock();
 373
 374         return rx_slave;
 375 }
 376
 377 /* teach the switch the mac of a disabled slave
 378  * on the primary for fault tolerance
 379  *
 380  * Caller must hold RTNL
 381  */
 382 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 383 {
 384         struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
 385
 386         if (!curr_active)
 387                 return;
 388
 389         if (!bond->alb_info.primary_is_promisc) {
 390                 if (!dev_set_promiscuity(curr_active->dev, 1))
 391                         bond->alb_info.primary_is_promisc = 1;
 392                 else
 393                         bond->alb_info.primary_is_promisc = 0;
 394         }
 395
 396         bond->alb_info.rlb_promisc_timeout_counter = 0;
 397
 398         alb_send_learning_packets(curr_active, addr, true);
 399 }
 400
 401 /* slave being removed should not be active at this point
 402  *
 403  * Caller must hold rtnl.
 404  */
 405 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 406 {
 407         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 408         struct rlb_client_info *rx_hash_table;
 409         u32 index, next_index;
 410
 411         /* clear slave from rx_hashtbl */
 412         spin_lock_bh(&bond->mode_lock);
 413
 414         rx_hash_table = bond_info->rx_hashtbl;
 415         index = bond_info->rx_hashtbl_used_head;
 416         for (; index != RLB_NULL_INDEX; index = next_index) {
 417                 next_index = rx_hash_table[index].used_next;
 418                 if (rx_hash_table[index].slave == slave) {
 419                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 420
 421                         if (assigned_slave) {
 422                                 rx_hash_table[index].slave = assigned_slave;
 423                                 if (!ether_addr_equal_64bits(rx_hash_table[index].mac_dst,
 424                                                              mac_bcast)) {
 425                                         bond_info->rx_hashtbl[index].ntt = 1;
 426                                         bond_info->rx_ntt = 1;
 427                                         /* A slave has been removed from the
 428                                          * table because it is either disabled
 429                                          * or being released. We must retry the
 430                                          * update to avoid clients from not
 431                                          * being updated & disconnecting when
 432                                          * there is stress
 433                                          */
 434                                         bond_info->rlb_update_retry_counter =
 435                                                 RLB_UPDATE_RETRY;
 436                                 }
 437                         } else {  /* there is no active slave */
 438                                 rx_hash_table[index].slave = NULL;
 439                         }
 440                 }
 441         }
 442
 443         spin_unlock_bh(&bond->mode_lock);
 444
 445         if (slave != rtnl_dereference(bond->curr_active_slave))
 446                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 447 }
 448
 449 static void rlb_update_client(struct rlb_client_info *client_info)
 450 {
 451         int i;
 452
 453         if (!client_info->slave)
 454                 return;
 455
 456         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 457                 struct sk_buff *skb;
 458
 459                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 460                                  client_info->ip_dst,
 461                                  client_info->slave->dev,
 462                                  client_info->ip_src,
 463                                  client_info->mac_dst,
 464                                  client_info->slave->dev->dev_addr,
 465                                  client_info->mac_dst);
 466                 if (!skb) {
 467                         netdev_err(client_info->slave->bond->dev,
 468                                    "failed to create an ARP packet\n");
 469                         continue;
 470                 }
 471
 472                 skb->dev = client_info->slave->dev;
 473
 474                 if (client_info->vlan_id) {
 475                         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 476                                                client_info->vlan_id);
 477                 }
 478
 479                 arp_xmit(skb);
 480         }
 481 }
 482
 483 /* sends ARP REPLIES that update the clients that need updating */
 484 static void rlb_update_rx_clients(struct bonding *bond)
 485 {
 486         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 487         struct rlb_client_info *client_info;
 488         u32 hash_index;
 489
 490         spin_lock_bh(&bond->mode_lock);
 491
 492         hash_index = bond_info->rx_hashtbl_used_head;
 493         for (; hash_index != RLB_NULL_INDEX;
 494              hash_index = client_info->used_next) {
 495                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 496                 if (client_info->ntt) {
 497                         rlb_update_client(client_info);
 498                         if (bond_info->rlb_update_retry_counter == 0)
 499                                 client_info->ntt = 0;
 500                 }
 501         }
 502
 503         /* do not update the entries again until this counter is zero so that
 504          * not to confuse the clients.
 505          */
 506         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 507
 508         spin_unlock_bh(&bond->mode_lock);
 509 }
 510
 511 /* The slave was assigned a new mac address - update the clients */
 512 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 513 {
 514         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 515         struct rlb_client_info *client_info;
 516         int ntt = 0;
 517         u32 hash_index;
 518
 519         spin_lock_bh(&bond->mode_lock);
 520
 521         hash_index = bond_info->rx_hashtbl_used_head;
 522         for (; hash_index != RLB_NULL_INDEX;
 523              hash_index = client_info->used_next) {
 524                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 525
 526                 if ((client_info->slave == slave) &&
 527                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 528                         client_info->ntt = 1;
 529                         ntt = 1;
 530                 }
 531         }
 532
 533         /* update the team's flag only after the whole iteration */
 534         if (ntt) {
 535                 bond_info->rx_ntt = 1;
 536                 /* fasten the change */
 537                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 538         }
 539
 540         spin_unlock_bh(&bond->mode_lock);
 541 }
 542
 543 /* mark all clients using src_ip to be updated */
 544 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 545 {
 546         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 547         struct rlb_client_info *client_info;
 548         u32 hash_index;
 549
 550         spin_lock(&bond->mode_lock);
 551
 552         hash_index = bond_info->rx_hashtbl_used_head;
 553         for (; hash_index != RLB_NULL_INDEX;
 554              hash_index = client_info->used_next) {
 555                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 556
 557                 if (!client_info->slave) {
 558                         netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
 559                         continue;
 560                 }
 561                 /* update all clients using this src_ip, that are not assigned
 562                  * to the team's address (curr_active_slave) and have a known
 563                  * unicast mac address.
 564                  */
 565                 if ((client_info->ip_src == src_ip) &&
 566                     !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 567                                              bond->dev->dev_addr) &&
 568                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 569                         client_info->ntt = 1;
 570                         bond_info->rx_ntt = 1;
 571                 }
 572         }
 573
 574         spin_unlock(&bond->mode_lock);
 575 }
 576
 577 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 578 {
 579         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 580         struct arp_pkt *arp = arp_pkt(skb);
 581         struct slave *assigned_slave, *curr_active_slave;
 582         struct rlb_client_info *client_info;
 583         u32 hash_index = 0;
 584
 585         spin_lock(&bond->mode_lock);
 586
 587         curr_active_slave = rcu_dereference(bond->curr_active_slave);
 588
 589         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 590         client_info = &(bond_info->rx_hashtbl[hash_index]);
 591
 592         if (client_info->assigned) {
 593                 if ((client_info->ip_src == arp->ip_src) &&
 594                     (client_info->ip_dst == arp->ip_dst)) {
 595                         /* the entry is already assigned to this client */
 596                         if (!ether_addr_equal_64bits(arp->mac_dst, mac_bcast)) {
 597                                 /* update mac address from arp */
 598                                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 599                         }
 600                         ether_addr_copy(client_info->mac_src, arp->mac_src);
 601
 602                         assigned_slave = client_info->slave;
 603                         if (assigned_slave) {
 604                                 spin_unlock(&bond->mode_lock);
 605                                 return assigned_slave;
 606                         }
 607                 } else {
 608                         /* the entry is already assigned to some other client,
 609                          * move the old client to primary (curr_active_slave) so
 610                          * that the new client can be assigned to this entry.
 611                          */
 612                         if (curr_active_slave &&
 613                             client_info->slave != curr_active_slave) {
 614                                 client_info->slave = curr_active_slave;
 615                                 rlb_update_client(client_info);
 616                         }
 617                 }
 618         }
 619         /* assign a new slave */
 620         assigned_slave = __rlb_next_rx_slave(bond);
 621
 622         if (assigned_slave) {
 623                 if (!(client_info->assigned &&
 624                       client_info->ip_src == arp->ip_src)) {
 625                         /* ip_src is going to be updated,
 626                          * fix the src hash list
 627                          */
 628                         u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 629                                                     sizeof(arp->ip_src));
 630                         rlb_src_unlink(bond, hash_index);
 631                         rlb_src_link(bond, hash_src, hash_index);
 632                 }
 633
 634                 client_info->ip_src = arp->ip_src;
 635                 client_info->ip_dst = arp->ip_dst;
 636                 /* arp->mac_dst is broadcast for arp reqeusts.
 637                  * will be updated with clients actual unicast mac address
 638                  * upon receiving an arp reply.
 639                  */
 640                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 641                 ether_addr_copy(client_info->mac_src, arp->mac_src);
 642                 client_info->slave = assigned_slave;
 643
 644                 if (!ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 645                         client_info->ntt = 1;
 646                         bond->alb_info.rx_ntt = 1;
 647                 } else {
 648                         client_info->ntt = 0;
 649                 }
 650
 651                 if (vlan_get_tag(skb, &client_info->vlan_id))
 652                         client_info->vlan_id = 0;
 653
 654                 if (!client_info->assigned) {
 655                         u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 656                         bond_info->rx_hashtbl_used_head = hash_index;
 657                         client_info->used_next = prev_tbl_head;
 658                         if (prev_tbl_head != RLB_NULL_INDEX) {
 659                                 bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 660                                         hash_index;
 661                         }
 662                         client_info->assigned = 1;
 663                 }
 664         }
 665
 666         spin_unlock(&bond->mode_lock);
 667
 668         return assigned_slave;
 669 }
 670
 671 /* chooses (and returns) transmit channel for arp reply
 672  * does not choose channel for other arp types since they are
 673  * sent on the curr_active_slave
 674  */
 675 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 676 {
 677         struct arp_pkt *arp = arp_pkt(skb);
 678         struct slave *tx_slave = NULL;
 679
 680         /* Don't modify or load balance ARPs that do not originate locally
 681          * (e.g.,arrive via a bridge).
 682          */
 683         if (!bond_slave_has_mac_rx(bond, arp->mac_src))
 684                 return NULL;
 685
 686         if (arp->op_code == htons(ARPOP_REPLY)) {
 687                 /* the arp must be sent on the selected rx channel */
 688                 tx_slave = rlb_choose_channel(skb, bond);
 689                 if (tx_slave)
 690                         ether_addr_copy(arp->mac_src, tx_slave->dev->dev_addr);
 691                 netdev_dbg(bond->dev, "Server sent ARP Reply packet\n");
 692         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 693                 /* Create an entry in the rx_hashtbl for this client as a
 694                  * place holder.
 695                  * When the arp reply is received the entry will be updated
 696                  * with the correct unicast address of the client.
 697                  */
 698                 rlb_choose_channel(skb, bond);
 699
 700                 /* The ARP reply packets must be delayed so that
 701                  * they can cancel out the influence of the ARP request.
 702                  */
 703                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 704
 705                 /* arp requests are broadcast and are sent on the primary
 706                  * the arp request will collapse all clients on the subnet to
 707                  * the primary slave. We must register these clients to be
 708                  * updated with their assigned mac.
 709                  */
 710                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 711                 netdev_dbg(bond->dev, "Server sent ARP Request packet\n");
 712         }
 713
 714         return tx_slave;
 715 }
 716
 717 static void rlb_rebalance(struct bonding *bond)
 718 {
 719         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 720         struct slave *assigned_slave;
 721         struct rlb_client_info *client_info;
 722         int ntt;
 723         u32 hash_index;
 724
 725         spin_lock_bh(&bond->mode_lock);
 726
 727         ntt = 0;
 728         hash_index = bond_info->rx_hashtbl_used_head;
 729         for (; hash_index != RLB_NULL_INDEX;
 730              hash_index = client_info->used_next) {
 731                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 732                 assigned_slave = __rlb_next_rx_slave(bond);
 733                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 734                         client_info->slave = assigned_slave;
 735                         client_info->ntt = 1;
 736                         ntt = 1;
 737                 }
 738         }
 739
 740         /* update the team's flag only after the whole iteration */
 741         if (ntt)
 742                 bond_info->rx_ntt = 1;
 743         spin_unlock_bh(&bond->mode_lock);
 744 }
 745
 746 /* Caller must hold mode_lock */
 747 static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 748 {
 749         entry->used_next = RLB_NULL_INDEX;
 750         entry->used_prev = RLB_NULL_INDEX;
 751         entry->assigned = 0;
 752         entry->slave = NULL;
 753         entry->vlan_id = 0;
 754 }
 755 static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 756 {
 757         entry->src_first = RLB_NULL_INDEX;
 758         entry->src_prev = RLB_NULL_INDEX;
 759         entry->src_next = RLB_NULL_INDEX;
 760 }
 761
 762 static void rlb_init_table_entry(struct rlb_client_info *entry)
 763 {
 764         memset(entry, 0, sizeof(struct rlb_client_info));
 765         rlb_init_table_entry_dst(entry);
 766         rlb_init_table_entry_src(entry);
 767 }
 768
 769 static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 770 {
 771         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 772         u32 next_index = bond_info->rx_hashtbl[index].used_next;
 773         u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 774
 775         if (index == bond_info->rx_hashtbl_used_head)
 776                 bond_info->rx_hashtbl_used_head = next_index;
 777         if (prev_index != RLB_NULL_INDEX)
 778                 bond_info->rx_hashtbl[prev_index].used_next = next_index;
 779         if (next_index != RLB_NULL_INDEX)
 780                 bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 781 }
 782
 783 /* unlink a rlb hash table entry from the src list */
 784 static void rlb_src_unlink(struct bonding *bond, u32 index)
 785 {
 786         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 787         u32 next_index = bond_info->rx_hashtbl[index].src_next;
 788         u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 789
 790         bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 791         bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 792
 793         if (next_index != RLB_NULL_INDEX)
 794                 bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 795
 796         if (prev_index == RLB_NULL_INDEX)
 797                 return;
 798
 799         /* is prev_index pointing to the head of this list? */
 800         if (bond_info->rx_hashtbl[prev_index].src_first == index)
 801                 bond_info->rx_hashtbl[prev_index].src_first = next_index;
 802         else
 803                 bond_info->rx_hashtbl[prev_index].src_next = next_index;
 804
 805 }
 806
 807 static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 808 {
 809         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 810         struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 811
 812         rlb_delete_table_entry_dst(bond, index);
 813         rlb_init_table_entry_dst(entry);
 814
 815         rlb_src_unlink(bond, index);
 816 }
 817
 818 /* add the rx_hashtbl[ip_dst_hash] entry to the list
 819  * of entries with identical ip_src_hash
 820  */
 821 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 822 {
 823         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 824         u32 next;
 825
 826         bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 827         next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 828         bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 829         if (next != RLB_NULL_INDEX)
 830                 bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 831         bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 832 }
 833
 834 /* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
 835  * not match arp->mac_src
 836  */
 837 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 838 {
 839         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 840         u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 841         u32 index;
 842
 843         spin_lock_bh(&bond->mode_lock);
 844
 845         index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 846         while (index != RLB_NULL_INDEX) {
 847                 struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 848                 u32 next_index = entry->src_next;
 849                 if (entry->ip_src == arp->ip_src &&
 850                     !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 851                                 rlb_delete_table_entry(bond, index);
 852                 index = next_index;
 853         }
 854         spin_unlock_bh(&bond->mode_lock);
 855 }
 856
 857 static int rlb_initialize(struct bonding *bond)
 858 {
 859         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 860         struct rlb_client_info  *new_hashtbl;
 861         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 862         int i;
 863
 864         new_hashtbl = kmalloc(size, GFP_KERNEL);
 865         if (!new_hashtbl)
 866                 return -1;
 867
 868         spin_lock_bh(&bond->mode_lock);
 869
 870         bond_info->rx_hashtbl = new_hashtbl;
 871
 872         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 873
 874         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 875                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 876
 877         spin_unlock_bh(&bond->mode_lock);
 878
 879         /* register to receive ARPs */
 880         bond->recv_probe = rlb_arp_recv;
 881
 882         return 0;
 883 }
 884
 885 static void rlb_deinitialize(struct bonding *bond)
 886 {
 887         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 888
 889         spin_lock_bh(&bond->mode_lock);
 890
 891         kfree(bond_info->rx_hashtbl);
 892         bond_info->rx_hashtbl = NULL;
 893         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 894
 895         spin_unlock_bh(&bond->mode_lock);
 896 }
 897
 898 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 899 {
 900         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 901         u32 curr_index;
 902
 903         spin_lock_bh(&bond->mode_lock);
 904
 905         curr_index = bond_info->rx_hashtbl_used_head;
 906         while (curr_index != RLB_NULL_INDEX) {
 907                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 908                 u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 909
 910                 if (curr->vlan_id == vlan_id)
 911                         rlb_delete_table_entry(bond, curr_index);
 912
 913                 curr_index = next_index;
 914         }
 915
 916         spin_unlock_bh(&bond->mode_lock);
 917 }
 918
 919 /*********************** tlb/rlb shared functions *********************/
 920
 921 static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
 922                             __be16 vlan_proto, u16 vid)
 923 {
 924         struct learning_pkt pkt;
 925         struct sk_buff *skb;
 926         int size = sizeof(struct learning_pkt);
 927         char *data;
 928
 929         memset(&pkt, 0, size);
 930         ether_addr_copy(pkt.mac_dst, mac_addr);
 931         ether_addr_copy(pkt.mac_src, mac_addr);
 932         pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
 933
 934         skb = dev_alloc_skb(size);
 935         if (!skb)
 936                 return;
 937
 938         data = skb_put(skb, size);
 939         memcpy(data, &pkt, size);
 940
 941         skb_reset_mac_header(skb);
 942         skb->network_header = skb->mac_header + ETH_HLEN;
 943         skb->protocol = pkt.type;
 944         skb->priority = TC_PRIO_CONTROL;
 945         skb->dev = slave->dev;
 946
 947         if (vid)
 948                 __vlan_hwaccel_put_tag(skb, vlan_proto, vid);
 949
 950         dev_queue_xmit(skb);
 951 }
 952
 953 struct alb_walk_data {
 954         struct bonding *bond;
 955         struct slave *slave;
 956         u8 *mac_addr;
 957         bool strict_match;
 958 };
 959
 960 static int alb_upper_dev_walk(struct net_device *upper, void *_data)
 961 {
 962         struct alb_walk_data *data = _data;
 963         bool strict_match = data->strict_match;
 964         struct bonding *bond = data->bond;
 965         struct slave *slave = data->slave;
 966         u8 *mac_addr = data->mac_addr;
 967         struct bond_vlan_tag *tags;
 968
 969         if (is_vlan_dev(upper) && vlan_get_encap_level(upper) == 0) {
 970                 if (strict_match &&
 971                     ether_addr_equal_64bits(mac_addr,
 972                                             upper->dev_addr)) {
 973                         alb_send_lp_vid(slave, mac_addr,
 974                                         vlan_dev_vlan_proto(upper),
 975                                         vlan_dev_vlan_id(upper));
 976                 } else if (!strict_match) {
 977                         alb_send_lp_vid(slave, upper->dev_addr,
 978                                         vlan_dev_vlan_proto(upper),
 979                                         vlan_dev_vlan_id(upper));
 980                 }
 981         }
 982
 983         /* If this is a macvlan device, then only send updates
 984          * when strict_match is turned off.
 985          */
 986         if (netif_is_macvlan(upper) && !strict_match) {
 987                 tags = bond_verify_device_path(bond->dev, upper, 0);
 988                 if (IS_ERR_OR_NULL(tags))
 989                         BUG();
 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
 998 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
 999                                       bool strict_match)
1000 {
1001         struct bonding *bond = bond_get_bond_by_slave(slave);
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         /* send untagged */
1010         alb_send_lp_vid(slave, mac_addr, 0, 0);
1011
1012         /* loop through all devices and see if we need to send a packet
1013          * for that device.
1014          */
1015         rcu_read_lock();
1016         netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &data);
1017         rcu_read_unlock();
1018 }
1019
1020 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
1021 {
1022         struct net_device *dev = slave->dev;
1023         struct sockaddr s_addr;
1024
1025         if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1026                 memcpy(dev->dev_addr, addr, dev->addr_len);
1027                 return 0;
1028         }
1029
1030         /* for rlb each slave must have a unique hw mac addresses so that
1031          * each slave will receive packets destined to a different mac
1032          */
1033         memcpy(s_addr.sa_data, addr, dev->addr_len);
1034         s_addr.sa_family = dev->type;
1035         if (dev_set_mac_address(dev, &s_addr)) {
1036                 netdev_err(slave->bond->dev, "dev_set_mac_address of dev %s failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
1037                            dev->name);
1038                 return -EOPNOTSUPP;
1039         }
1040         return 0;
1041 }
1042
1043 /* Swap MAC addresses between two slaves.
1044  *
1045  * Called with RTNL held, and no other locks.
1046  */
1047 static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1048 {
1049         u8 tmp_mac_addr[ETH_ALEN];
1050
1051         ether_addr_copy(tmp_mac_addr, slave1->dev->dev_addr);
1052         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
1053         alb_set_slave_mac_addr(slave2, tmp_mac_addr);
1054
1055 }
1056
1057 /* Send learning packets after MAC address swap.
1058  *
1059  * Called with RTNL and no other locks
1060  */
1061 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1062                                 struct slave *slave2)
1063 {
1064         int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1065         struct slave *disabled_slave = NULL;
1066
1067         ASSERT_RTNL();
1068
1069         /* fasten the change in the switch */
1070         if (bond_slave_can_tx(slave1)) {
1071                 alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1072                 if (bond->alb_info.rlb_enabled) {
1073                         /* inform the clients that the mac address
1074                          * has changed
1075                          */
1076                         rlb_req_update_slave_clients(bond, slave1);
1077                 }
1078         } else {
1079                 disabled_slave = slave1;
1080         }
1081
1082         if (bond_slave_can_tx(slave2)) {
1083                 alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1084                 if (bond->alb_info.rlb_enabled) {
1085                         /* inform the clients that the mac address
1086                          * has changed
1087                          */
1088                         rlb_req_update_slave_clients(bond, slave2);
1089                 }
1090         } else {
1091                 disabled_slave = slave2;
1092         }
1093
1094         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1095                 /* A disabled slave was assigned an active mac addr */
1096                 rlb_teach_disabled_mac_on_primary(bond,
1097                                                   disabled_slave->dev->dev_addr);
1098         }
1099 }
1100
1101 /**
1102  * alb_change_hw_addr_on_detach
1103  * @bond: bonding we're working on
1104  * @slave: the slave that was just detached
1105  *
1106  * We assume that @slave was already detached from the slave list.
1107  *
1108  * If @slave's permanent hw address is different both from its current
1109  * address and from @bond's address, then somewhere in the bond there's
1110  * a slave that has @slave's permanet address as its current address.
1111  * We'll make sure that that slave no longer uses @slave's permanent address.
1112  *
1113  * Caller must hold RTNL and no other locks
1114  */
1115 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1116 {
1117         int perm_curr_diff;
1118         int perm_bond_diff;
1119         struct slave *found_slave;
1120
1121         perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1122                                                   slave->dev->dev_addr);
1123         perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1124                                                   bond->dev->dev_addr);
1125
1126         if (perm_curr_diff && perm_bond_diff) {
1127                 found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1128
1129                 if (found_slave) {
1130                         alb_swap_mac_addr(slave, found_slave);
1131                         alb_fasten_mac_swap(bond, slave, found_slave);
1132                 }
1133         }
1134 }
1135
1136 /**
1137  * alb_handle_addr_collision_on_attach
1138  * @bond: bonding we're working on
1139  * @slave: the slave that was just attached
1140  *
1141  * checks uniqueness of slave's mac address and handles the case the
1142  * new slave uses the bonds mac address.
1143  *
1144  * If the permanent hw address of @slave is @bond's hw address, we need to
1145  * find a different hw address to give @slave, that isn't in use by any other
1146  * slave in the bond. This address must be, of course, one of the permanent
1147  * addresses of the other slaves.
1148  *
1149  * We go over the slave list, and for each slave there we compare its
1150  * permanent hw address with the current address of all the other slaves.
1151  * If no match was found, then we've found a slave with a permanent address
1152  * that isn't used by any other slave in the bond, so we can assign it to
1153  * @slave.
1154  *
1155  * assumption: this function is called before @slave is attached to the
1156  *             bond slave list.
1157  */
1158 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1159 {
1160         struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1161         struct slave *tmp_slave1, *free_mac_slave = NULL;
1162         struct list_head *iter;
1163
1164         if (!bond_has_slaves(bond)) {
1165                 /* this is the first slave */
1166                 return 0;
1167         }
1168
1169         /* if slave's mac address differs from bond's mac address
1170          * check uniqueness of slave's mac address against the other
1171          * slaves in the bond.
1172          */
1173         if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1174                 if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1175                         return 0;
1176
1177                 /* Try setting slave mac to bond address and fall-through
1178                  * to code handling that situation below...
1179                  */
1180                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1181         }
1182
1183         /* The slave's address is equal to the address of the bond.
1184          * Search for a spare address in the bond for this slave.
1185          */
1186         bond_for_each_slave(bond, tmp_slave1, iter) {
1187                 if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1188                         /* no slave has tmp_slave1's perm addr
1189                          * as its curr addr
1190                          */
1191                         free_mac_slave = tmp_slave1;
1192                         break;
1193                 }
1194
1195                 if (!has_bond_addr) {
1196                         if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1197                                                     bond->dev->dev_addr)) {
1198
1199                                 has_bond_addr = tmp_slave1;
1200                         }
1201                 }
1202         }
1203
1204         if (free_mac_slave) {
1205                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1206
1207                 netdev_warn(bond->dev, "the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1208                             slave->dev->name, free_mac_slave->dev->name);
1209
1210         } else if (has_bond_addr) {
1211                 netdev_err(bond->dev, "the hw address of slave %s 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",
1212                            slave->dev->name);
1213                 return -EFAULT;
1214         }
1215
1216         return 0;
1217 }
1218
1219 /**
1220  * alb_set_mac_address
1221  * @bond:
1222  * @addr:
1223  *
1224  * In TLB mode all slaves are configured to the bond's hw address, but set
1225  * their dev_addr field to different addresses (based on their permanent hw
1226  * addresses).
1227  *
1228  * For each slave, this function sets the interface to the new address and then
1229  * changes its dev_addr field to its previous value.
1230  *
1231  * Unwinding assumes bond's mac address has not yet changed.
1232  */
1233 static int alb_set_mac_address(struct bonding *bond, void *addr)
1234 {
1235         struct slave *slave, *rollback_slave;
1236         struct list_head *iter;
1237         struct sockaddr sa;
1238         char tmp_addr[ETH_ALEN];
1239         int res;
1240
1241         if (bond->alb_info.rlb_enabled)
1242                 return 0;
1243
1244         bond_for_each_slave(bond, slave, iter) {
1245                 /* save net_device's current hw address */
1246                 ether_addr_copy(tmp_addr, slave->dev->dev_addr);
1247
1248                 res = dev_set_mac_address(slave->dev, addr);
1249
1250                 /* restore net_device's hw address */
1251                 ether_addr_copy(slave->dev->dev_addr, tmp_addr);
1252
1253                 if (res)
1254                         goto unwind;
1255         }
1256
1257         return 0;
1258
1259 unwind:
1260         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1261         sa.sa_family = bond->dev->type;
1262
1263         /* unwind from head to the slave that failed */
1264         bond_for_each_slave(bond, rollback_slave, iter) {
1265                 if (rollback_slave == slave)
1266                         break;
1267                 ether_addr_copy(tmp_addr, rollback_slave->dev->dev_addr);
1268                 dev_set_mac_address(rollback_slave->dev, &sa);
1269                 ether_addr_copy(rollback_slave->dev->dev_addr, tmp_addr);
1270         }
1271
1272         return res;
1273 }
1274
1275 /************************ exported alb funcions ************************/
1276
1277 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1278 {
1279         int res;
1280
1281         res = tlb_initialize(bond);
1282         if (res)
1283                 return res;
1284
1285         if (rlb_enabled) {
1286                 bond->alb_info.rlb_enabled = 1;
1287                 res = rlb_initialize(bond);
1288                 if (res) {
1289                         tlb_deinitialize(bond);
1290                         return res;
1291                 }
1292         } else {
1293                 bond->alb_info.rlb_enabled = 0;
1294         }
1295
1296         return 0;
1297 }
1298
1299 void bond_alb_deinitialize(struct bonding *bond)
1300 {
1301         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1302
1303         tlb_deinitialize(bond);
1304
1305         if (bond_info->rlb_enabled)
1306                 rlb_deinitialize(bond);
1307 }
1308
1309 static int bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1310                             struct slave *tx_slave)
1311 {
1312         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1313         struct ethhdr *eth_data = eth_hdr(skb);
1314
1315         if (!tx_slave) {
1316                 /* unbalanced or unassigned, send through primary */
1317                 tx_slave = rcu_dereference(bond->curr_active_slave);
1318                 if (bond->params.tlb_dynamic_lb)
1319                         bond_info->unbalanced_load += skb->len;
1320         }
1321
1322         if (tx_slave && bond_slave_can_tx(tx_slave)) {
1323                 if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1324                         ether_addr_copy(eth_data->h_source,
1325                                         tx_slave->dev->dev_addr);
1326                 }
1327
1328                 bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1329                 goto out;
1330         }
1331
1332         if (tx_slave && bond->params.tlb_dynamic_lb) {
1333                 spin_lock(&bond->mode_lock);
1334                 __tlb_clear_slave(bond, tx_slave, 0);
1335                 spin_unlock(&bond->mode_lock);
1336         }
1337
1338         /* no suitable interface, frame not sent */
1339         bond_tx_drop(bond->dev, skb);
1340 out:
1341         return NETDEV_TX_OK;
1342 }
1343
1344 int bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1345 {
1346         struct bonding *bond = netdev_priv(bond_dev);
1347         struct ethhdr *eth_data;
1348         struct slave *tx_slave = NULL;
1349         u32 hash_index;
1350
1351         skb_reset_mac_header(skb);
1352         eth_data = eth_hdr(skb);
1353
1354         /* Do not TX balance any multicast or broadcast */
1355         if (!is_multicast_ether_addr(eth_data->h_dest)) {
1356                 switch (skb->protocol) {
1357                 case htons(ETH_P_IP):
1358                 case htons(ETH_P_IPX):
1359                     /* In case of IPX, it will falback to L2 hash */
1360                 case htons(ETH_P_IPV6):
1361                         hash_index = bond_xmit_hash(bond, skb);
1362                         if (bond->params.tlb_dynamic_lb) {
1363                                 tx_slave = tlb_choose_channel(bond,
1364                                                               hash_index & 0xFF,
1365                                                               skb->len);
1366                         } else {
1367                                 struct bond_up_slave *slaves;
1368                                 unsigned int count;
1369
1370                                 slaves = rcu_dereference(bond->slave_arr);
1371                                 count = slaves ? ACCESS_ONCE(slaves->count) : 0;
1372                                 if (likely(count))
1373                                         tx_slave = slaves->arr[hash_index %
1374                                                                count];
1375                         }
1376                         break;
1377                 }
1378         }
1379         return bond_do_alb_xmit(skb, bond, tx_slave);
1380 }
1381
1382 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1383 {
1384         struct bonding *bond = netdev_priv(bond_dev);
1385         struct ethhdr *eth_data;
1386         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1387         struct slave *tx_slave = NULL;
1388         static const __be32 ip_bcast = htonl(0xffffffff);
1389         int hash_size = 0;
1390         bool do_tx_balance = true;
1391         u32 hash_index = 0;
1392         const u8 *hash_start = NULL;
1393         struct ipv6hdr *ip6hdr;
1394
1395         skb_reset_mac_header(skb);
1396         eth_data = eth_hdr(skb);
1397
1398         switch (ntohs(skb->protocol)) {
1399         case ETH_P_IP: {
1400                 const struct iphdr *iph = ip_hdr(skb);
1401
1402                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast) ||
1403                     (iph->daddr == ip_bcast) ||
1404                     (iph->protocol == IPPROTO_IGMP)) {
1405                         do_tx_balance = false;
1406                         break;
1407                 }
1408                 hash_start = (char *)&(iph->daddr);
1409                 hash_size = sizeof(iph->daddr);
1410         }
1411                 break;
1412         case ETH_P_IPV6:
1413                 /* IPv6 doesn't really use broadcast mac address, but leave
1414                  * that here just in case.
1415                  */
1416                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast)) {
1417                         do_tx_balance = false;
1418                         break;
1419                 }
1420
1421                 /* IPv6 uses all-nodes multicast as an equivalent to
1422                  * broadcasts in IPv4.
1423                  */
1424                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1425                         do_tx_balance = false;
1426                         break;
1427                 }
1428
1429                 /* Additianally, DAD probes should not be tx-balanced as that
1430                  * will lead to false positives for duplicate addresses and
1431                  * prevent address configuration from working.
1432                  */
1433                 ip6hdr = ipv6_hdr(skb);
1434                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1435                         do_tx_balance = false;
1436                         break;
1437                 }
1438
1439                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1440                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1441                 break;
1442         case ETH_P_IPX:
1443                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1444                         /* something is wrong with this packet */
1445                         do_tx_balance = false;
1446                         break;
1447                 }
1448
1449                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1450                         /* The only protocol worth balancing in
1451                          * this family since it has an "ARP" like
1452                          * mechanism
1453                          */
1454                         do_tx_balance = false;
1455                         break;
1456                 }
1457
1458                 hash_start = (char *)eth_data->h_dest;
1459                 hash_size = ETH_ALEN;
1460                 break;
1461         case ETH_P_ARP:
1462                 do_tx_balance = false;
1463                 if (bond_info->rlb_enabled)
1464                         tx_slave = rlb_arp_xmit(skb, bond);
1465                 break;
1466         default:
1467                 do_tx_balance = false;
1468                 break;
1469         }
1470
1471         if (do_tx_balance) {
1472                 hash_index = _simple_hash(hash_start, hash_size);
1473                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1474         }
1475
1476         return bond_do_alb_xmit(skb, bond, tx_slave);
1477 }
1478
1479 void bond_alb_monitor(struct work_struct *work)
1480 {
1481         struct bonding *bond = container_of(work, struct bonding,
1482                                             alb_work.work);
1483         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1484         struct list_head *iter;
1485         struct slave *slave;
1486
1487         if (!bond_has_slaves(bond)) {
1488                 bond_info->tx_rebalance_counter = 0;
1489                 bond_info->lp_counter = 0;
1490                 goto re_arm;
1491         }
1492
1493         rcu_read_lock();
1494
1495         bond_info->tx_rebalance_counter++;
1496         bond_info->lp_counter++;
1497
1498         /* send learning packets */
1499         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1500                 bool strict_match;
1501
1502                 bond_for_each_slave_rcu(bond, slave, iter) {
1503                         /* If updating current_active, use all currently
1504                          * user mac addreses (!strict_match).  Otherwise, only
1505                          * use mac of the slave device.
1506                          * In RLB mode, we always use strict matches.
1507                          */
1508                         strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1509                                         bond_info->rlb_enabled);
1510                         alb_send_learning_packets(slave, slave->dev->dev_addr,
1511                                                   strict_match);
1512                 }
1513                 bond_info->lp_counter = 0;
1514         }
1515
1516         /* rebalance tx traffic */
1517         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1518                 bond_for_each_slave_rcu(bond, slave, iter) {
1519                         tlb_clear_slave(bond, slave, 1);
1520                         if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1521                                 SLAVE_TLB_INFO(slave).load =
1522                                         bond_info->unbalanced_load /
1523                                                 BOND_TLB_REBALANCE_INTERVAL;
1524                                 bond_info->unbalanced_load = 0;
1525                         }
1526                 }
1527                 bond_info->tx_rebalance_counter = 0;
1528         }
1529
1530         if (bond_info->rlb_enabled) {
1531                 if (bond_info->primary_is_promisc &&
1532                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1533
1534                         /* dev_set_promiscuity requires rtnl and
1535                          * nothing else.  Avoid race with bond_close.
1536                          */
1537                         rcu_read_unlock();
1538                         if (!rtnl_trylock())
1539                                 goto re_arm;
1540
1541                         bond_info->rlb_promisc_timeout_counter = 0;
1542
1543                         /* If the primary was set to promiscuous mode
1544                          * because a slave was disabled then
1545                          * it can now leave promiscuous mode.
1546                          */
1547                         dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1548                                             -1);
1549                         bond_info->primary_is_promisc = 0;
1550
1551                         rtnl_unlock();
1552                         rcu_read_lock();
1553                 }
1554
1555                 if (bond_info->rlb_rebalance) {
1556                         bond_info->rlb_rebalance = 0;
1557                         rlb_rebalance(bond);
1558                 }
1559
1560                 /* check if clients need updating */
1561                 if (bond_info->rx_ntt) {
1562                         if (bond_info->rlb_update_delay_counter) {
1563                                 --bond_info->rlb_update_delay_counter;
1564                         } else {
1565                                 rlb_update_rx_clients(bond);
1566                                 if (bond_info->rlb_update_retry_counter)
1567                                         --bond_info->rlb_update_retry_counter;
1568                                 else
1569                                         bond_info->rx_ntt = 0;
1570                         }
1571                 }
1572         }
1573         rcu_read_unlock();
1574 re_arm:
1575         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1576 }
1577
1578 /* assumption: called before the slave is attached to the bond
1579  * and not locked by the bond lock
1580  */
1581 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1582 {
1583         int res;
1584
1585         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1586         if (res)
1587                 return res;
1588
1589         res = alb_handle_addr_collision_on_attach(bond, slave);
1590         if (res)
1591                 return res;
1592
1593         tlb_init_slave(slave);
1594
1595         /* order a rebalance ASAP */
1596         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1597
1598         if (bond->alb_info.rlb_enabled)
1599                 bond->alb_info.rlb_rebalance = 1;
1600
1601         return 0;
1602 }
1603
1604 /* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1605  * if necessary.
1606  *
1607  * Caller must hold RTNL and no other locks
1608  */
1609 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1610 {
1611         if (bond_has_slaves(bond))
1612                 alb_change_hw_addr_on_detach(bond, slave);
1613
1614         tlb_clear_slave(bond, slave, 0);
1615
1616         if (bond->alb_info.rlb_enabled) {
1617                 bond->alb_info.rx_slave = NULL;
1618                 rlb_clear_slave(bond, slave);
1619         }
1620
1621 }
1622
1623 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1624 {
1625         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1626
1627         if (link == BOND_LINK_DOWN) {
1628                 tlb_clear_slave(bond, slave, 0);
1629                 if (bond->alb_info.rlb_enabled)
1630                         rlb_clear_slave(bond, slave);
1631         } else if (link == BOND_LINK_UP) {
1632                 /* order a rebalance ASAP */
1633                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1634                 if (bond->alb_info.rlb_enabled) {
1635                         bond->alb_info.rlb_rebalance = 1;
1636                         /* If the updelay module parameter is smaller than the
1637                          * forwarding delay of the switch the rebalance will
1638                          * not work because the rebalance arp replies will
1639                          * not be forwarded to the clients..
1640                          */
1641                 }
1642         }
1643
1644         if (bond_is_nondyn_tlb(bond)) {
1645                 if (bond_update_slave_arr(bond, NULL))
1646                         pr_err("Failed to build slave-array for TLB mode.\n");
1647         }
1648 }
1649
1650 /**
1651  * bond_alb_handle_active_change - assign new curr_active_slave
1652  * @bond: our bonding struct
1653  * @new_slave: new slave to assign
1654  *
1655  * Set the bond->curr_active_slave to @new_slave and handle
1656  * mac address swapping and promiscuity changes as needed.
1657  *
1658  * Caller must hold RTNL
1659  */
1660 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1661 {
1662         struct slave *swap_slave;
1663         struct slave *curr_active;
1664
1665         curr_active = rtnl_dereference(bond->curr_active_slave);
1666         if (curr_active == new_slave)
1667                 return;
1668
1669         if (curr_active && bond->alb_info.primary_is_promisc) {
1670                 dev_set_promiscuity(curr_active->dev, -1);
1671                 bond->alb_info.primary_is_promisc = 0;
1672                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1673         }
1674
1675         swap_slave = curr_active;
1676         rcu_assign_pointer(bond->curr_active_slave, new_slave);
1677
1678         if (!new_slave || !bond_has_slaves(bond))
1679                 return;
1680
1681         /* set the new curr_active_slave to the bonds mac address
1682          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1683          */
1684         if (!swap_slave)
1685                 swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1686
1687         /* Arrange for swap_slave and new_slave to temporarily be
1688          * ignored so we can mess with their MAC addresses without
1689          * fear of interference from transmit activity.
1690          */
1691         if (swap_slave)
1692                 tlb_clear_slave(bond, swap_slave, 1);
1693         tlb_clear_slave(bond, new_slave, 1);
1694
1695         /* in TLB mode, the slave might flip down/up with the old dev_addr,
1696          * and thus filter bond->dev_addr's packets, so force bond's mac
1697          */
1698         if (BOND_MODE(bond) == BOND_MODE_TLB) {
1699                 struct sockaddr sa;
1700                 u8 tmp_addr[ETH_ALEN];
1701
1702                 ether_addr_copy(tmp_addr, new_slave->dev->dev_addr);
1703
1704                 memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1705                 sa.sa_family = bond->dev->type;
1706                 /* we don't care if it can't change its mac, best effort */
1707                 dev_set_mac_address(new_slave->dev, &sa);
1708
1709                 ether_addr_copy(new_slave->dev->dev_addr, tmp_addr);
1710         }
1711
1712         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1713         if (swap_slave) {
1714                 /* swap mac address */
1715                 alb_swap_mac_addr(swap_slave, new_slave);
1716                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1717         } else {
1718                 /* set the new_slave to the bond mac address */
1719                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1720                 alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1721                                           false);
1722         }
1723 }
1724
1725 /* Called with RTNL */
1726 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1727 {
1728         struct bonding *bond = netdev_priv(bond_dev);
1729         struct sockaddr *sa = addr;
1730         struct slave *curr_active;
1731         struct slave *swap_slave;
1732         int res;
1733
1734         if (!is_valid_ether_addr(sa->sa_data))
1735                 return -EADDRNOTAVAIL;
1736
1737         res = alb_set_mac_address(bond, addr);
1738         if (res)
1739                 return res;
1740
1741         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1742
1743         /* If there is no curr_active_slave there is nothing else to do.
1744          * Otherwise we'll need to pass the new address to it and handle
1745          * duplications.
1746          */
1747         curr_active = rtnl_dereference(bond->curr_active_slave);
1748         if (!curr_active)
1749                 return 0;
1750
1751         swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1752
1753         if (swap_slave) {
1754                 alb_swap_mac_addr(swap_slave, curr_active);
1755                 alb_fasten_mac_swap(bond, swap_slave, curr_active);
1756         } else {
1757                 alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr);
1758
1759                 alb_send_learning_packets(curr_active,
1760                                           bond_dev->dev_addr, false);
1761                 if (bond->alb_info.rlb_enabled) {
1762                         /* inform clients mac address has changed */
1763                         rlb_req_update_slave_clients(bond, curr_active);
1764                 }
1765         }
1766
1767         return 0;
1768 }
1769
1770 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1771 {
1772         if (bond->alb_info.rlb_enabled)
1773                 rlb_clear_vlan(bond, vlan_id);
1774 }
1775