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, write to the Free Software Foundation, Inc.,
  16  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  */
  22
  23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  24
  25 #include <linux/skbuff.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/pkt_sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/slab.h>
  31 #include <linux/timer.h>
  32 #include <linux/ip.h>
  33 #include <linux/ipv6.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/if_ether.h>
  36 #include <linux/if_bonding.h>
  37 #include <linux/if_vlan.h>
  38 #include <linux/in.h>
  39 #include <net/ipx.h>
  40 #include <net/arp.h>
  41 #include <net/ipv6.h>
  42 #include <asm/byteorder.h>
  43 #include "bonding.h"
  44 #include "bond_alb.h"
  45
  46
  47
  48 #ifndef __long_aligned
  49 #define __long_aligned __attribute__((aligned((sizeof(long)))))
  50 #endif
  51 static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
  52         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  53 };
  54 static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
  55         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  56 };
  57 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  58
  59 #pragma pack(1)
  60 struct learning_pkt {
  61         u8 mac_dst[ETH_ALEN];
  62         u8 mac_src[ETH_ALEN];
  63         __be16 type;
  64         u8 padding[ETH_ZLEN - ETH_HLEN];
  65 };
  66
  67 struct arp_pkt {
  68         __be16  hw_addr_space;
  69         __be16  prot_addr_space;
  70         u8      hw_addr_len;
  71         u8      prot_addr_len;
  72         __be16  op_code;
  73         u8      mac_src[ETH_ALEN];      /* sender hardware address */
  74         __be32  ip_src;                 /* sender IP address */
  75         u8      mac_dst[ETH_ALEN];      /* target hardware address */
  76         __be32  ip_dst;                 /* target IP address */
  77 };
  78 #pragma pack()
  79
  80 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
  81 {
  82         return (struct arp_pkt *)skb_network_header(skb);
  83 }
  84
  85 /* Forward declaration */
  86 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
  87
  88 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  89 {
  90         int i;
  91         u8 hash = 0;
  92
  93         for (i = 0; i < hash_size; i++) {
  94                 hash ^= hash_start[i];
  95         }
  96
  97         return hash;
  98 }
  99
 100 /*********************** tlb specific functions ***************************/
 101
 102 static inline void _lock_tx_hashtbl(struct bonding *bond)
 103 {
 104         spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 105 }
 106
 107 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 108 {
 109         spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 110 }
 111
 112 /* Caller must hold tx_hashtbl lock */
 113 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 114 {
 115         if (save_load) {
 116                 entry->load_history = 1 + entry->tx_bytes /
 117                                       BOND_TLB_REBALANCE_INTERVAL;
 118                 entry->tx_bytes = 0;
 119         }
 120
 121         entry->tx_slave = NULL;
 122         entry->next = TLB_NULL_INDEX;
 123         entry->prev = TLB_NULL_INDEX;
 124 }
 125
 126 static inline void tlb_init_slave(struct slave *slave)
 127 {
 128         SLAVE_TLB_INFO(slave).load = 0;
 129         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 130 }
 131
 132 /* Caller must hold bond lock for read */
 133 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
 134 {
 135         struct tlb_client_info *tx_hash_table;
 136         u32 index;
 137
 138         _lock_tx_hashtbl(bond);
 139
 140         /* clear slave from tx_hashtbl */
 141         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 142
 143         /* skip this if we've already freed the tx hash table */
 144         if (tx_hash_table) {
 145                 index = SLAVE_TLB_INFO(slave).head;
 146                 while (index != TLB_NULL_INDEX) {
 147                         u32 next_index = tx_hash_table[index].next;
 148                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 149                         index = next_index;
 150                 }
 151         }
 152
 153         tlb_init_slave(slave);
 154
 155         _unlock_tx_hashtbl(bond);
 156 }
 157
 158 /* Must be called before starting the monitor timer */
 159 static int tlb_initialize(struct bonding *bond)
 160 {
 161         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 162         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 163         struct tlb_client_info *new_hashtbl;
 164         int i;
 165
 166         new_hashtbl = kzalloc(size, GFP_KERNEL);
 167         if (!new_hashtbl) {
 168                 pr_err("%s: Error: Failed to allocate TLB hash table\n",
 169                        bond->dev->name);
 170                 return -1;
 171         }
 172         _lock_tx_hashtbl(bond);
 173
 174         bond_info->tx_hashtbl = new_hashtbl;
 175
 176         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 177                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 178         }
 179
 180         _unlock_tx_hashtbl(bond);
 181
 182         return 0;
 183 }
 184
 185 /* Must be called only after all slaves have been released */
 186 static void tlb_deinitialize(struct bonding *bond)
 187 {
 188         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 189
 190         _lock_tx_hashtbl(bond);
 191
 192         kfree(bond_info->tx_hashtbl);
 193         bond_info->tx_hashtbl = NULL;
 194
 195         _unlock_tx_hashtbl(bond);
 196 }
 197
 198 static long long compute_gap(struct slave *slave)
 199 {
 200         return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 201                (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 202 }
 203
 204 /* Caller must hold bond lock for read */
 205 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 206 {
 207         struct slave *slave, *least_loaded;
 208         long long max_gap;
 209         int i;
 210
 211         least_loaded = NULL;
 212         max_gap = LLONG_MIN;
 213
 214         /* Find the slave with the largest gap */
 215         bond_for_each_slave(bond, slave, i) {
 216                 if (SLAVE_IS_OK(slave)) {
 217                         long long gap = compute_gap(slave);
 218
 219                         if (max_gap < gap) {
 220                                 least_loaded = slave;
 221                                 max_gap = gap;
 222                         }
 223                 }
 224         }
 225
 226         return least_loaded;
 227 }
 228
 229 /* Caller must hold bond lock for read */
 230 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
 231 {
 232         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 233         struct tlb_client_info *hash_table;
 234         struct slave *assigned_slave;
 235
 236         _lock_tx_hashtbl(bond);
 237
 238         hash_table = bond_info->tx_hashtbl;
 239         assigned_slave = hash_table[hash_index].tx_slave;
 240         if (!assigned_slave) {
 241                 assigned_slave = tlb_get_least_loaded_slave(bond);
 242
 243                 if (assigned_slave) {
 244                         struct tlb_slave_info *slave_info =
 245                                 &(SLAVE_TLB_INFO(assigned_slave));
 246                         u32 next_index = slave_info->head;
 247
 248                         hash_table[hash_index].tx_slave = assigned_slave;
 249                         hash_table[hash_index].next = next_index;
 250                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 251
 252                         if (next_index != TLB_NULL_INDEX) {
 253                                 hash_table[next_index].prev = hash_index;
 254                         }
 255
 256                         slave_info->head = hash_index;
 257                         slave_info->load +=
 258                                 hash_table[hash_index].load_history;
 259                 }
 260         }
 261
 262         if (assigned_slave) {
 263                 hash_table[hash_index].tx_bytes += skb_len;
 264         }
 265
 266         _unlock_tx_hashtbl(bond);
 267
 268         return assigned_slave;
 269 }
 270
 271 /*********************** rlb specific functions ***************************/
 272 static inline void _lock_rx_hashtbl(struct bonding *bond)
 273 {
 274         spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 275 }
 276
 277 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 278 {
 279         spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 280 }
 281
 282 /* when an ARP REPLY is received from a client update its info
 283  * in the rx_hashtbl
 284  */
 285 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 286 {
 287         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 288         struct rlb_client_info *client_info;
 289         u32 hash_index;
 290
 291         _lock_rx_hashtbl(bond);
 292
 293         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 294         client_info = &(bond_info->rx_hashtbl[hash_index]);
 295
 296         if ((client_info->assigned) &&
 297             (client_info->ip_src == arp->ip_dst) &&
 298             (client_info->ip_dst == arp->ip_src) &&
 299             (compare_ether_addr_64bits(client_info->mac_dst, arp->mac_src))) {
 300                 /* update the clients MAC address */
 301                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 302                 client_info->ntt = 1;
 303                 bond_info->rx_ntt = 1;
 304         }
 305
 306         _unlock_rx_hashtbl(bond);
 307 }
 308
 309 static void rlb_arp_recv(struct sk_buff *skb, struct bonding *bond,
 310                          struct slave *slave)
 311 {
 312         struct arp_pkt *arp;
 313
 314         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 315                 return;
 316
 317         arp = (struct arp_pkt *) skb->data;
 318         if (!arp) {
 319                 pr_debug("Packet has no ARP data\n");
 320                 return;
 321         }
 322
 323         if (!pskb_may_pull(skb, arp_hdr_len(bond->dev)))
 324                 return;
 325
 326         if (skb->len < sizeof(struct arp_pkt)) {
 327                 pr_debug("Packet is too small to be an ARP\n");
 328                 return;
 329         }
 330
 331         if (arp->op_code == htons(ARPOP_REPLY)) {
 332                 /* update rx hash table for this ARP */
 333                 rlb_update_entry_from_arp(bond, arp);
 334                 pr_debug("Server received an ARP Reply from client\n");
 335         }
 336 }
 337
 338 /* Caller must hold bond lock for read */
 339 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 340 {
 341         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 342         struct slave *rx_slave, *slave, *start_at;
 343         int i = 0;
 344
 345         if (bond_info->next_rx_slave) {
 346                 start_at = bond_info->next_rx_slave;
 347         } else {
 348                 start_at = bond->first_slave;
 349         }
 350
 351         rx_slave = NULL;
 352
 353         bond_for_each_slave_from(bond, slave, i, start_at) {
 354                 if (SLAVE_IS_OK(slave)) {
 355                         if (!rx_slave) {
 356                                 rx_slave = slave;
 357                         } else if (slave->speed > rx_slave->speed) {
 358                                 rx_slave = slave;
 359                         }
 360                 }
 361         }
 362
 363         if (rx_slave) {
 364                 bond_info->next_rx_slave = rx_slave->next;
 365         }
 366
 367         return rx_slave;
 368 }
 369
 370 /* teach the switch the mac of a disabled slave
 371  * on the primary for fault tolerance
 372  *
 373  * Caller must hold bond->curr_slave_lock for write or bond lock for write
 374  */
 375 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 376 {
 377         if (!bond->curr_active_slave) {
 378                 return;
 379         }
 380
 381         if (!bond->alb_info.primary_is_promisc) {
 382                 if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
 383                         bond->alb_info.primary_is_promisc = 1;
 384                 else
 385                         bond->alb_info.primary_is_promisc = 0;
 386         }
 387
 388         bond->alb_info.rlb_promisc_timeout_counter = 0;
 389
 390         alb_send_learning_packets(bond->curr_active_slave, addr);
 391 }
 392
 393 /* slave being removed should not be active at this point
 394  *
 395  * Caller must hold bond lock for read
 396  */
 397 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 398 {
 399         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 400         struct rlb_client_info *rx_hash_table;
 401         u32 index, next_index;
 402
 403         /* clear slave from rx_hashtbl */
 404         _lock_rx_hashtbl(bond);
 405
 406         rx_hash_table = bond_info->rx_hashtbl;
 407         index = bond_info->rx_hashtbl_head;
 408         for (; index != RLB_NULL_INDEX; index = next_index) {
 409                 next_index = rx_hash_table[index].next;
 410                 if (rx_hash_table[index].slave == slave) {
 411                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 412
 413                         if (assigned_slave) {
 414                                 rx_hash_table[index].slave = assigned_slave;
 415                                 if (compare_ether_addr_64bits(rx_hash_table[index].mac_dst,
 416                                                               mac_bcast)) {
 417                                         bond_info->rx_hashtbl[index].ntt = 1;
 418                                         bond_info->rx_ntt = 1;
 419                                         /* A slave has been removed from the
 420                                          * table because it is either disabled
 421                                          * or being released. We must retry the
 422                                          * update to avoid clients from not
 423                                          * being updated & disconnecting when
 424                                          * there is stress
 425                                          */
 426                                         bond_info->rlb_update_retry_counter =
 427                                                 RLB_UPDATE_RETRY;
 428                                 }
 429                         } else {  /* there is no active slave */
 430                                 rx_hash_table[index].slave = NULL;
 431                         }
 432                 }
 433         }
 434
 435         _unlock_rx_hashtbl(bond);
 436
 437         write_lock_bh(&bond->curr_slave_lock);
 438
 439         if (slave != bond->curr_active_slave) {
 440                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 441         }
 442
 443         write_unlock_bh(&bond->curr_slave_lock);
 444 }
 445
 446 static void rlb_update_client(struct rlb_client_info *client_info)
 447 {
 448         int i;
 449
 450         if (!client_info->slave) {
 451                 return;
 452         }
 453
 454         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 455                 struct sk_buff *skb;
 456
 457                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 458                                  client_info->ip_dst,
 459                                  client_info->slave->dev,
 460                                  client_info->ip_src,
 461                                  client_info->mac_dst,
 462                                  client_info->slave->dev->dev_addr,
 463                                  client_info->mac_dst);
 464                 if (!skb) {
 465                         pr_err("%s: Error: failed to create an ARP packet\n",
 466                                client_info->slave->dev->master->name);
 467                         continue;
 468                 }
 469
 470                 skb->dev = client_info->slave->dev;
 471
 472                 if (client_info->tag) {
 473                         skb = vlan_put_tag(skb, client_info->vlan_id);
 474                         if (!skb) {
 475                                 pr_err("%s: Error: failed to insert VLAN tag\n",
 476                                        client_info->slave->dev->master->name);
 477                                 continue;
 478                         }
 479                 }
 480
 481                 arp_xmit(skb);
 482         }
 483 }
 484
 485 /* sends ARP REPLIES that update the clients that need updating */
 486 static void rlb_update_rx_clients(struct bonding *bond)
 487 {
 488         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 489         struct rlb_client_info *client_info;
 490         u32 hash_index;
 491
 492         _lock_rx_hashtbl(bond);
 493
 494         hash_index = bond_info->rx_hashtbl_head;
 495         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 496                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 497                 if (client_info->ntt) {
 498                         rlb_update_client(client_info);
 499                         if (bond_info->rlb_update_retry_counter == 0) {
 500                                 client_info->ntt = 0;
 501                         }
 502                 }
 503         }
 504
 505         /* do not update the entries again until this counter is zero so that
 506          * not to confuse the clients.
 507          */
 508         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 509
 510         _unlock_rx_hashtbl(bond);
 511 }
 512
 513 /* The slave was assigned a new mac address - update the clients */
 514 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 515 {
 516         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 517         struct rlb_client_info *client_info;
 518         int ntt = 0;
 519         u32 hash_index;
 520
 521         _lock_rx_hashtbl(bond);
 522
 523         hash_index = bond_info->rx_hashtbl_head;
 524         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 525                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 526
 527                 if ((client_info->slave == slave) &&
 528                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 529                         client_info->ntt = 1;
 530                         ntt = 1;
 531                 }
 532         }
 533
 534         // update the team's flag only after the whole iteration
 535         if (ntt) {
 536                 bond_info->rx_ntt = 1;
 537                 //fasten the change
 538                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 539         }
 540
 541         _unlock_rx_hashtbl(bond);
 542 }
 543
 544 /* mark all clients using src_ip to be updated */
 545 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 546 {
 547         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 548         struct rlb_client_info *client_info;
 549         u32 hash_index;
 550
 551         _lock_rx_hashtbl(bond);
 552
 553         hash_index = bond_info->rx_hashtbl_head;
 554         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 555                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 556
 557                 if (!client_info->slave) {
 558                         pr_err("%s: Error: found a client with no channel in the client's hash table\n",
 559                                bond->dev->name);
 560                         continue;
 561                 }
 562                 /*update all clients using this src_ip, that are not assigned
 563                  * to the team's address (curr_active_slave) and have a known
 564                  * unicast mac address.
 565                  */
 566                 if ((client_info->ip_src == src_ip) &&
 567                     compare_ether_addr_64bits(client_info->slave->dev->dev_addr,
 568                            bond->dev->dev_addr) &&
 569                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 570                         client_info->ntt = 1;
 571                         bond_info->rx_ntt = 1;
 572                 }
 573         }
 574
 575         _unlock_rx_hashtbl(bond);
 576 }
 577
 578 /* Caller must hold both bond and ptr locks for read */
 579 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 580 {
 581         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 582         struct arp_pkt *arp = arp_pkt(skb);
 583         struct slave *assigned_slave;
 584         struct rlb_client_info *client_info;
 585         u32 hash_index = 0;
 586
 587         _lock_rx_hashtbl(bond);
 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 (compare_ether_addr_64bits(arp->mac_dst, mac_bcast)) {
 597                                 /* update mac address from arp */
 598                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 599                         }
 600
 601                         assigned_slave = client_info->slave;
 602                         if (assigned_slave) {
 603                                 _unlock_rx_hashtbl(bond);
 604                                 return assigned_slave;
 605                         }
 606                 } else {
 607                         /* the entry is already assigned to some other client,
 608                          * move the old client to primary (curr_active_slave) so
 609                          * that the new client can be assigned to this entry.
 610                          */
 611                         if (bond->curr_active_slave &&
 612                             client_info->slave != bond->curr_active_slave) {
 613                                 client_info->slave = bond->curr_active_slave;
 614                                 rlb_update_client(client_info);
 615                         }
 616                 }
 617         }
 618         /* assign a new slave */
 619         assigned_slave = rlb_next_rx_slave(bond);
 620
 621         if (assigned_slave) {
 622                 client_info->ip_src = arp->ip_src;
 623                 client_info->ip_dst = arp->ip_dst;
 624                 /* arp->mac_dst is broadcast for arp reqeusts.
 625                  * will be updated with clients actual unicast mac address
 626                  * upon receiving an arp reply.
 627                  */
 628                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 629                 client_info->slave = assigned_slave;
 630
 631                 if (compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 632                         client_info->ntt = 1;
 633                         bond->alb_info.rx_ntt = 1;
 634                 } else {
 635                         client_info->ntt = 0;
 636                 }
 637
 638                 if (bond_vlan_used(bond)) {
 639                         if (!vlan_get_tag(skb, &client_info->vlan_id))
 640                                 client_info->tag = 1;
 641                 }
 642
 643                 if (!client_info->assigned) {
 644                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
 645                         bond_info->rx_hashtbl_head = hash_index;
 646                         client_info->next = prev_tbl_head;
 647                         if (prev_tbl_head != RLB_NULL_INDEX) {
 648                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
 649                                         hash_index;
 650                         }
 651                         client_info->assigned = 1;
 652                 }
 653         }
 654
 655         _unlock_rx_hashtbl(bond);
 656
 657         return assigned_slave;
 658 }
 659
 660 /* chooses (and returns) transmit channel for arp reply
 661  * does not choose channel for other arp types since they are
 662  * sent on the curr_active_slave
 663  */
 664 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 665 {
 666         struct arp_pkt *arp = arp_pkt(skb);
 667         struct slave *tx_slave = NULL;
 668
 669         if (arp->op_code == htons(ARPOP_REPLY)) {
 670                 /* the arp must be sent on the selected
 671                 * rx channel
 672                 */
 673                 tx_slave = rlb_choose_channel(skb, bond);
 674                 if (tx_slave) {
 675                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
 676                 }
 677                 pr_debug("Server sent ARP Reply packet\n");
 678         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 679                 /* Create an entry in the rx_hashtbl for this client as a
 680                  * place holder.
 681                  * When the arp reply is received the entry will be updated
 682                  * with the correct unicast address of the client.
 683                  */
 684                 rlb_choose_channel(skb, bond);
 685
 686                 /* The ARP reply packets must be delayed so that
 687                  * they can cancel out the influence of the ARP request.
 688                  */
 689                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 690
 691                 /* arp requests are broadcast and are sent on the primary
 692                  * the arp request will collapse all clients on the subnet to
 693                  * the primary slave. We must register these clients to be
 694                  * updated with their assigned mac.
 695                  */
 696                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 697                 pr_debug("Server sent ARP Request packet\n");
 698         }
 699
 700         return tx_slave;
 701 }
 702
 703 /* Caller must hold bond lock for read */
 704 static void rlb_rebalance(struct bonding *bond)
 705 {
 706         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 707         struct slave *assigned_slave;
 708         struct rlb_client_info *client_info;
 709         int ntt;
 710         u32 hash_index;
 711
 712         _lock_rx_hashtbl(bond);
 713
 714         ntt = 0;
 715         hash_index = bond_info->rx_hashtbl_head;
 716         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 717                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 718                 assigned_slave = rlb_next_rx_slave(bond);
 719                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 720                         client_info->slave = assigned_slave;
 721                         client_info->ntt = 1;
 722                         ntt = 1;
 723                 }
 724         }
 725
 726         /* update the team's flag only after the whole iteration */
 727         if (ntt) {
 728                 bond_info->rx_ntt = 1;
 729         }
 730         _unlock_rx_hashtbl(bond);
 731 }
 732
 733 /* Caller must hold rx_hashtbl lock */
 734 static void rlb_init_table_entry(struct rlb_client_info *entry)
 735 {
 736         memset(entry, 0, sizeof(struct rlb_client_info));
 737         entry->next = RLB_NULL_INDEX;
 738         entry->prev = RLB_NULL_INDEX;
 739 }
 740
 741 static int rlb_initialize(struct bonding *bond)
 742 {
 743         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 744         struct rlb_client_info  *new_hashtbl;
 745         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 746         int i;
 747
 748         new_hashtbl = kmalloc(size, GFP_KERNEL);
 749         if (!new_hashtbl) {
 750                 pr_err("%s: Error: Failed to allocate RLB hash table\n",
 751                        bond->dev->name);
 752                 return -1;
 753         }
 754         _lock_rx_hashtbl(bond);
 755
 756         bond_info->rx_hashtbl = new_hashtbl;
 757
 758         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 759
 760         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
 761                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 762         }
 763
 764         _unlock_rx_hashtbl(bond);
 765
 766         /* register to receive ARPs */
 767         bond->recv_probe = rlb_arp_recv;
 768
 769         return 0;
 770 }
 771
 772 static void rlb_deinitialize(struct bonding *bond)
 773 {
 774         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 775
 776         _lock_rx_hashtbl(bond);
 777
 778         kfree(bond_info->rx_hashtbl);
 779         bond_info->rx_hashtbl = NULL;
 780         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 781
 782         _unlock_rx_hashtbl(bond);
 783 }
 784
 785 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 786 {
 787         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 788         u32 curr_index;
 789
 790         _lock_rx_hashtbl(bond);
 791
 792         curr_index = bond_info->rx_hashtbl_head;
 793         while (curr_index != RLB_NULL_INDEX) {
 794                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 795                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
 796                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
 797
 798                 if (curr->tag && (curr->vlan_id == vlan_id)) {
 799                         if (curr_index == bond_info->rx_hashtbl_head) {
 800                                 bond_info->rx_hashtbl_head = next_index;
 801                         }
 802                         if (prev_index != RLB_NULL_INDEX) {
 803                                 bond_info->rx_hashtbl[prev_index].next = next_index;
 804                         }
 805                         if (next_index != RLB_NULL_INDEX) {
 806                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
 807                         }
 808
 809                         rlb_init_table_entry(curr);
 810                 }
 811
 812                 curr_index = next_index;
 813         }
 814
 815         _unlock_rx_hashtbl(bond);
 816 }
 817
 818 /*********************** tlb/rlb shared functions *********************/
 819
 820 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
 821 {
 822         struct bonding *bond = bond_get_bond_by_slave(slave);
 823         struct learning_pkt pkt;
 824         int size = sizeof(struct learning_pkt);
 825         int i;
 826
 827         memset(&pkt, 0, size);
 828         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
 829         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
 830         pkt.type = cpu_to_be16(ETH_P_LOOP);
 831
 832         for (i = 0; i < MAX_LP_BURST; i++) {
 833                 struct sk_buff *skb;
 834                 char *data;
 835
 836                 skb = dev_alloc_skb(size);
 837                 if (!skb) {
 838                         return;
 839                 }
 840
 841                 data = skb_put(skb, size);
 842                 memcpy(data, &pkt, size);
 843
 844                 skb_reset_mac_header(skb);
 845                 skb->network_header = skb->mac_header + ETH_HLEN;
 846                 skb->protocol = pkt.type;
 847                 skb->priority = TC_PRIO_CONTROL;
 848                 skb->dev = slave->dev;
 849
 850                 if (bond_vlan_used(bond)) {
 851                         struct vlan_entry *vlan;
 852
 853                         vlan = bond_next_vlan(bond,
 854                                               bond->alb_info.current_alb_vlan);
 855
 856                         bond->alb_info.current_alb_vlan = vlan;
 857                         if (!vlan) {
 858                                 kfree_skb(skb);
 859                                 continue;
 860                         }
 861
 862                         skb = vlan_put_tag(skb, vlan->vlan_id);
 863                         if (!skb) {
 864                                 pr_err("%s: Error: failed to insert VLAN tag\n",
 865                                        bond->dev->name);
 866                                 continue;
 867                         }
 868                 }
 869
 870                 dev_queue_xmit(skb);
 871         }
 872 }
 873
 874 /* hw is a boolean parameter that determines whether we should try and
 875  * set the hw address of the device as well as the hw address of the
 876  * net_device
 877  */
 878 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
 879 {
 880         struct net_device *dev = slave->dev;
 881         struct sockaddr s_addr;
 882
 883         if (!hw) {
 884                 memcpy(dev->dev_addr, addr, dev->addr_len);
 885                 return 0;
 886         }
 887
 888         /* for rlb each slave must have a unique hw mac addresses so that */
 889         /* each slave will receive packets destined to a different mac */
 890         memcpy(s_addr.sa_data, addr, dev->addr_len);
 891         s_addr.sa_family = dev->type;
 892         if (dev_set_mac_address(dev, &s_addr)) {
 893                 pr_err("%s: Error: dev_set_mac_address of dev %s failed!\n"
 894                        "ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
 895                        dev->master->name, dev->name);
 896                 return -EOPNOTSUPP;
 897         }
 898         return 0;
 899 }
 900
 901 /*
 902  * Swap MAC addresses between two slaves.
 903  *
 904  * Called with RTNL held, and no other locks.
 905  *
 906  */
 907
 908 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
 909 {
 910         u8 tmp_mac_addr[ETH_ALEN];
 911
 912         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
 913         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
 914         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
 915
 916 }
 917
 918 /*
 919  * Send learning packets after MAC address swap.
 920  *
 921  * Called with RTNL and no other locks
 922  */
 923 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
 924                                 struct slave *slave2)
 925 {
 926         int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
 927         struct slave *disabled_slave = NULL;
 928
 929         ASSERT_RTNL();
 930
 931         /* fasten the change in the switch */
 932         if (SLAVE_IS_OK(slave1)) {
 933                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
 934                 if (bond->alb_info.rlb_enabled) {
 935                         /* inform the clients that the mac address
 936                          * has changed
 937                          */
 938                         rlb_req_update_slave_clients(bond, slave1);
 939                 }
 940         } else {
 941                 disabled_slave = slave1;
 942         }
 943
 944         if (SLAVE_IS_OK(slave2)) {
 945                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
 946                 if (bond->alb_info.rlb_enabled) {
 947                         /* inform the clients that the mac address
 948                          * has changed
 949                          */
 950                         rlb_req_update_slave_clients(bond, slave2);
 951                 }
 952         } else {
 953                 disabled_slave = slave2;
 954         }
 955
 956         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
 957                 /* A disabled slave was assigned an active mac addr */
 958                 rlb_teach_disabled_mac_on_primary(bond,
 959                                                   disabled_slave->dev->dev_addr);
 960         }
 961 }
 962
 963 /**
 964  * alb_change_hw_addr_on_detach
 965  * @bond: bonding we're working on
 966  * @slave: the slave that was just detached
 967  *
 968  * We assume that @slave was already detached from the slave list.
 969  *
 970  * If @slave's permanent hw address is different both from its current
 971  * address and from @bond's address, then somewhere in the bond there's
 972  * a slave that has @slave's permanet address as its current address.
 973  * We'll make sure that that slave no longer uses @slave's permanent address.
 974  *
 975  * Caller must hold RTNL and no other locks
 976  */
 977 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
 978 {
 979         int perm_curr_diff;
 980         int perm_bond_diff;
 981
 982         perm_curr_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
 983                                                    slave->dev->dev_addr);
 984         perm_bond_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
 985                                                    bond->dev->dev_addr);
 986
 987         if (perm_curr_diff && perm_bond_diff) {
 988                 struct slave *tmp_slave;
 989                 int i, found = 0;
 990
 991                 bond_for_each_slave(bond, tmp_slave, i) {
 992                         if (!compare_ether_addr_64bits(slave->perm_hwaddr,
 993                                                        tmp_slave->dev->dev_addr)) {
 994                                 found = 1;
 995                                 break;
 996                         }
 997                 }
 998
 999                 if (found) {
1000                         /* locking: needs RTNL and nothing else */
1001                         alb_swap_mac_addr(bond, slave, tmp_slave);
1002                         alb_fasten_mac_swap(bond, slave, tmp_slave);
1003                 }
1004         }
1005 }
1006
1007 /**
1008  * alb_handle_addr_collision_on_attach
1009  * @bond: bonding we're working on
1010  * @slave: the slave that was just attached
1011  *
1012  * checks uniqueness of slave's mac address and handles the case the
1013  * new slave uses the bonds mac address.
1014  *
1015  * If the permanent hw address of @slave is @bond's hw address, we need to
1016  * find a different hw address to give @slave, that isn't in use by any other
1017  * slave in the bond. This address must be, of course, one of the permanent
1018  * addresses of the other slaves.
1019  *
1020  * We go over the slave list, and for each slave there we compare its
1021  * permanent hw address with the current address of all the other slaves.
1022  * If no match was found, then we've found a slave with a permanent address
1023  * that isn't used by any other slave in the bond, so we can assign it to
1024  * @slave.
1025  *
1026  * assumption: this function is called before @slave is attached to the
1027  *             bond slave list.
1028  *
1029  * caller must hold the bond lock for write since the mac addresses are compared
1030  * and may be swapped.
1031  */
1032 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1033 {
1034         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1035         struct slave *has_bond_addr = bond->curr_active_slave;
1036         int i, j, found = 0;
1037
1038         if (bond->slave_cnt == 0) {
1039                 /* this is the first slave */
1040                 return 0;
1041         }
1042
1043         /* if slave's mac address differs from bond's mac address
1044          * check uniqueness of slave's mac address against the other
1045          * slaves in the bond.
1046          */
1047         if (compare_ether_addr_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1048                 bond_for_each_slave(bond, tmp_slave1, i) {
1049                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1050                                                        slave->dev->dev_addr)) {
1051                                 found = 1;
1052                                 break;
1053                         }
1054                 }
1055
1056                 if (!found)
1057                         return 0;
1058
1059                 /* Try setting slave mac to bond address and fall-through
1060                    to code handling that situation below... */
1061                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1062                                        bond->alb_info.rlb_enabled);
1063         }
1064
1065         /* The slave's address is equal to the address of the bond.
1066          * Search for a spare address in the bond for this slave.
1067          */
1068         free_mac_slave = NULL;
1069
1070         bond_for_each_slave(bond, tmp_slave1, i) {
1071                 found = 0;
1072                 bond_for_each_slave(bond, tmp_slave2, j) {
1073                         if (!compare_ether_addr_64bits(tmp_slave1->perm_hwaddr,
1074                                                        tmp_slave2->dev->dev_addr)) {
1075                                 found = 1;
1076                                 break;
1077                         }
1078                 }
1079
1080                 if (!found) {
1081                         /* no slave has tmp_slave1's perm addr
1082                          * as its curr addr
1083                          */
1084                         free_mac_slave = tmp_slave1;
1085                         break;
1086                 }
1087
1088                 if (!has_bond_addr) {
1089                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1090                                                        bond->dev->dev_addr)) {
1091
1092                                 has_bond_addr = tmp_slave1;
1093                         }
1094                 }
1095         }
1096
1097         if (free_mac_slave) {
1098                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1099                                        bond->alb_info.rlb_enabled);
1100
1101                 pr_warning("%s: Warning: the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1102                            bond->dev->name, slave->dev->name,
1103                            free_mac_slave->dev->name);
1104
1105         } else if (has_bond_addr) {
1106                 pr_err("%s: Error: 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",
1107                        bond->dev->name, slave->dev->name);
1108                 return -EFAULT;
1109         }
1110
1111         return 0;
1112 }
1113
1114 /**
1115  * alb_set_mac_address
1116  * @bond:
1117  * @addr:
1118  *
1119  * In TLB mode all slaves are configured to the bond's hw address, but set
1120  * their dev_addr field to different addresses (based on their permanent hw
1121  * addresses).
1122  *
1123  * For each slave, this function sets the interface to the new address and then
1124  * changes its dev_addr field to its previous value.
1125  *
1126  * Unwinding assumes bond's mac address has not yet changed.
1127  */
1128 static int alb_set_mac_address(struct bonding *bond, void *addr)
1129 {
1130         struct sockaddr sa;
1131         struct slave *slave, *stop_at;
1132         char tmp_addr[ETH_ALEN];
1133         int res;
1134         int i;
1135
1136         if (bond->alb_info.rlb_enabled) {
1137                 return 0;
1138         }
1139
1140         bond_for_each_slave(bond, slave, i) {
1141                 /* save net_device's current hw address */
1142                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1143
1144                 res = dev_set_mac_address(slave->dev, addr);
1145
1146                 /* restore net_device's hw address */
1147                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1148
1149                 if (res)
1150                         goto unwind;
1151         }
1152
1153         return 0;
1154
1155 unwind:
1156         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1157         sa.sa_family = bond->dev->type;
1158
1159         /* unwind from head to the slave that failed */
1160         stop_at = slave;
1161         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1162                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1163                 dev_set_mac_address(slave->dev, &sa);
1164                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1165         }
1166
1167         return res;
1168 }
1169
1170 /************************ exported alb funcions ************************/
1171
1172 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1173 {
1174         int res;
1175
1176         res = tlb_initialize(bond);
1177         if (res) {
1178                 return res;
1179         }
1180
1181         if (rlb_enabled) {
1182                 bond->alb_info.rlb_enabled = 1;
1183                 /* initialize rlb */
1184                 res = rlb_initialize(bond);
1185                 if (res) {
1186                         tlb_deinitialize(bond);
1187                         return res;
1188                 }
1189         } else {
1190                 bond->alb_info.rlb_enabled = 0;
1191         }
1192
1193         return 0;
1194 }
1195
1196 void bond_alb_deinitialize(struct bonding *bond)
1197 {
1198         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1199
1200         tlb_deinitialize(bond);
1201
1202         if (bond_info->rlb_enabled) {
1203                 rlb_deinitialize(bond);
1204         }
1205 }
1206
1207 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1208 {
1209         struct bonding *bond = netdev_priv(bond_dev);
1210         struct ethhdr *eth_data;
1211         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1212         struct slave *tx_slave = NULL;
1213         static const __be32 ip_bcast = htonl(0xffffffff);
1214         int hash_size = 0;
1215         int do_tx_balance = 1;
1216         u32 hash_index = 0;
1217         const u8 *hash_start = NULL;
1218         int res = 1;
1219         struct ipv6hdr *ip6hdr;
1220
1221         skb_reset_mac_header(skb);
1222         eth_data = eth_hdr(skb);
1223
1224         /* make sure that the curr_active_slave do not change during tx
1225          */
1226         read_lock(&bond->curr_slave_lock);
1227
1228         switch (ntohs(skb->protocol)) {
1229         case ETH_P_IP: {
1230                 const struct iphdr *iph = ip_hdr(skb);
1231
1232                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast) ||
1233                     (iph->daddr == ip_bcast) ||
1234                     (iph->protocol == IPPROTO_IGMP)) {
1235                         do_tx_balance = 0;
1236                         break;
1237                 }
1238                 hash_start = (char *)&(iph->daddr);
1239                 hash_size = sizeof(iph->daddr);
1240         }
1241                 break;
1242         case ETH_P_IPV6:
1243                 /* IPv6 doesn't really use broadcast mac address, but leave
1244                  * that here just in case.
1245                  */
1246                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast)) {
1247                         do_tx_balance = 0;
1248                         break;
1249                 }
1250
1251                 /* IPv6 uses all-nodes multicast as an equivalent to
1252                  * broadcasts in IPv4.
1253                  */
1254                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1255                         do_tx_balance = 0;
1256                         break;
1257                 }
1258
1259                 /* Additianally, DAD probes should not be tx-balanced as that
1260                  * will lead to false positives for duplicate addresses and
1261                  * prevent address configuration from working.
1262                  */
1263                 ip6hdr = ipv6_hdr(skb);
1264                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1265                         do_tx_balance = 0;
1266                         break;
1267                 }
1268
1269                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1270                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1271                 break;
1272         case ETH_P_IPX:
1273                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1274                         /* something is wrong with this packet */
1275                         do_tx_balance = 0;
1276                         break;
1277                 }
1278
1279                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1280                         /* The only protocol worth balancing in
1281                          * this family since it has an "ARP" like
1282                          * mechanism
1283                          */
1284                         do_tx_balance = 0;
1285                         break;
1286                 }
1287
1288                 hash_start = (char*)eth_data->h_dest;
1289                 hash_size = ETH_ALEN;
1290                 break;
1291         case ETH_P_ARP:
1292                 do_tx_balance = 0;
1293                 if (bond_info->rlb_enabled) {
1294                         tx_slave = rlb_arp_xmit(skb, bond);
1295                 }
1296                 break;
1297         default:
1298                 do_tx_balance = 0;
1299                 break;
1300         }
1301
1302         if (do_tx_balance) {
1303                 hash_index = _simple_hash(hash_start, hash_size);
1304                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1305         }
1306
1307         if (!tx_slave) {
1308                 /* unbalanced or unassigned, send through primary */
1309                 tx_slave = bond->curr_active_slave;
1310                 bond_info->unbalanced_load += skb->len;
1311         }
1312
1313         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1314                 if (tx_slave != bond->curr_active_slave) {
1315                         memcpy(eth_data->h_source,
1316                                tx_slave->dev->dev_addr,
1317                                ETH_ALEN);
1318                 }
1319
1320                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1321         } else {
1322                 if (tx_slave) {
1323                         tlb_clear_slave(bond, tx_slave, 0);
1324                 }
1325         }
1326
1327         if (res) {
1328                 /* no suitable interface, frame not sent */
1329                 dev_kfree_skb(skb);
1330         }
1331         read_unlock(&bond->curr_slave_lock);
1332
1333         return NETDEV_TX_OK;
1334 }
1335
1336 void bond_alb_monitor(struct work_struct *work)
1337 {
1338         struct bonding *bond = container_of(work, struct bonding,
1339                                             alb_work.work);
1340         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1341         struct slave *slave;
1342         int i;
1343
1344         read_lock(&bond->lock);
1345
1346         if (bond->kill_timers) {
1347                 goto out;
1348         }
1349
1350         if (bond->slave_cnt == 0) {
1351                 bond_info->tx_rebalance_counter = 0;
1352                 bond_info->lp_counter = 0;
1353                 goto re_arm;
1354         }
1355
1356         bond_info->tx_rebalance_counter++;
1357         bond_info->lp_counter++;
1358
1359         /* send learning packets */
1360         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1361                 /* change of curr_active_slave involves swapping of mac addresses.
1362                  * in order to avoid this swapping from happening while
1363                  * sending the learning packets, the curr_slave_lock must be held for
1364                  * read.
1365                  */
1366                 read_lock(&bond->curr_slave_lock);
1367
1368                 bond_for_each_slave(bond, slave, i) {
1369                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1370                 }
1371
1372                 read_unlock(&bond->curr_slave_lock);
1373
1374                 bond_info->lp_counter = 0;
1375         }
1376
1377         /* rebalance tx traffic */
1378         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1379
1380                 read_lock(&bond->curr_slave_lock);
1381
1382                 bond_for_each_slave(bond, slave, i) {
1383                         tlb_clear_slave(bond, slave, 1);
1384                         if (slave == bond->curr_active_slave) {
1385                                 SLAVE_TLB_INFO(slave).load =
1386                                         bond_info->unbalanced_load /
1387                                                 BOND_TLB_REBALANCE_INTERVAL;
1388                                 bond_info->unbalanced_load = 0;
1389                         }
1390                 }
1391
1392                 read_unlock(&bond->curr_slave_lock);
1393
1394                 bond_info->tx_rebalance_counter = 0;
1395         }
1396
1397         /* handle rlb stuff */
1398         if (bond_info->rlb_enabled) {
1399                 if (bond_info->primary_is_promisc &&
1400                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1401
1402                         /*
1403                          * dev_set_promiscuity requires rtnl and
1404                          * nothing else.
1405                          */
1406                         read_unlock(&bond->lock);
1407                         rtnl_lock();
1408
1409                         bond_info->rlb_promisc_timeout_counter = 0;
1410
1411                         /* If the primary was set to promiscuous mode
1412                          * because a slave was disabled then
1413                          * it can now leave promiscuous mode.
1414                          */
1415                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1416                         bond_info->primary_is_promisc = 0;
1417
1418                         rtnl_unlock();
1419                         read_lock(&bond->lock);
1420                 }
1421
1422                 if (bond_info->rlb_rebalance) {
1423                         bond_info->rlb_rebalance = 0;
1424                         rlb_rebalance(bond);
1425                 }
1426
1427                 /* check if clients need updating */
1428                 if (bond_info->rx_ntt) {
1429                         if (bond_info->rlb_update_delay_counter) {
1430                                 --bond_info->rlb_update_delay_counter;
1431                         } else {
1432                                 rlb_update_rx_clients(bond);
1433                                 if (bond_info->rlb_update_retry_counter) {
1434                                         --bond_info->rlb_update_retry_counter;
1435                                 } else {
1436                                         bond_info->rx_ntt = 0;
1437                                 }
1438                         }
1439                 }
1440         }
1441
1442 re_arm:
1443         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1444 out:
1445         read_unlock(&bond->lock);
1446 }
1447
1448 /* assumption: called before the slave is attached to the bond
1449  * and not locked by the bond lock
1450  */
1451 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1452 {
1453         int res;
1454
1455         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1456                                      bond->alb_info.rlb_enabled);
1457         if (res) {
1458                 return res;
1459         }
1460
1461         /* caller must hold the bond lock for write since the mac addresses
1462          * are compared and may be swapped.
1463          */
1464         read_lock(&bond->lock);
1465
1466         res = alb_handle_addr_collision_on_attach(bond, slave);
1467
1468         read_unlock(&bond->lock);
1469
1470         if (res) {
1471                 return res;
1472         }
1473
1474         tlb_init_slave(slave);
1475
1476         /* order a rebalance ASAP */
1477         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1478
1479         if (bond->alb_info.rlb_enabled) {
1480                 bond->alb_info.rlb_rebalance = 1;
1481         }
1482
1483         return 0;
1484 }
1485
1486 /*
1487  * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1488  * if necessary.
1489  *
1490  * Caller must hold RTNL and no other locks
1491  */
1492 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1493 {
1494         if (bond->slave_cnt > 1) {
1495                 alb_change_hw_addr_on_detach(bond, slave);
1496         }
1497
1498         tlb_clear_slave(bond, slave, 0);
1499
1500         if (bond->alb_info.rlb_enabled) {
1501                 bond->alb_info.next_rx_slave = NULL;
1502                 rlb_clear_slave(bond, slave);
1503         }
1504 }
1505
1506 /* Caller must hold bond lock for read */
1507 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1508 {
1509         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1510
1511         if (link == BOND_LINK_DOWN) {
1512                 tlb_clear_slave(bond, slave, 0);
1513                 if (bond->alb_info.rlb_enabled) {
1514                         rlb_clear_slave(bond, slave);
1515                 }
1516         } else if (link == BOND_LINK_UP) {
1517                 /* order a rebalance ASAP */
1518                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1519                 if (bond->alb_info.rlb_enabled) {
1520                         bond->alb_info.rlb_rebalance = 1;
1521                         /* If the updelay module parameter is smaller than the
1522                          * forwarding delay of the switch the rebalance will
1523                          * not work because the rebalance arp replies will
1524                          * not be forwarded to the clients..
1525                          */
1526                 }
1527         }
1528 }
1529
1530 /**
1531  * bond_alb_handle_active_change - assign new curr_active_slave
1532  * @bond: our bonding struct
1533  * @new_slave: new slave to assign
1534  *
1535  * Set the bond->curr_active_slave to @new_slave and handle
1536  * mac address swapping and promiscuity changes as needed.
1537  *
1538  * If new_slave is NULL, caller must hold curr_slave_lock or
1539  * bond->lock for write.
1540  *
1541  * If new_slave is not NULL, caller must hold RTNL, bond->lock for
1542  * read and curr_slave_lock for write.  Processing here may sleep, so
1543  * no other locks may be held.
1544  */
1545 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1546         __releases(&bond->curr_slave_lock)
1547         __releases(&bond->lock)
1548         __acquires(&bond->lock)
1549         __acquires(&bond->curr_slave_lock)
1550 {
1551         struct slave *swap_slave;
1552         int i;
1553
1554         if (bond->curr_active_slave == new_slave) {
1555                 return;
1556         }
1557
1558         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1559                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1560                 bond->alb_info.primary_is_promisc = 0;
1561                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1562         }
1563
1564         swap_slave = bond->curr_active_slave;
1565         bond->curr_active_slave = new_slave;
1566
1567         if (!new_slave || (bond->slave_cnt == 0)) {
1568                 return;
1569         }
1570
1571         /* set the new curr_active_slave to the bonds mac address
1572          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1573          */
1574         if (!swap_slave) {
1575                 struct slave *tmp_slave;
1576                 /* find slave that is holding the bond's mac address */
1577                 bond_for_each_slave(bond, tmp_slave, i) {
1578                         if (!compare_ether_addr_64bits(tmp_slave->dev->dev_addr,
1579                                                        bond->dev->dev_addr)) {
1580                                 swap_slave = tmp_slave;
1581                                 break;
1582                         }
1583                 }
1584         }
1585
1586         /*
1587          * Arrange for swap_slave and new_slave to temporarily be
1588          * ignored so we can mess with their MAC addresses without
1589          * fear of interference from transmit activity.
1590          */
1591         if (swap_slave) {
1592                 tlb_clear_slave(bond, swap_slave, 1);
1593         }
1594         tlb_clear_slave(bond, new_slave, 1);
1595
1596         write_unlock_bh(&bond->curr_slave_lock);
1597         read_unlock(&bond->lock);
1598
1599         ASSERT_RTNL();
1600
1601         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1602         if (swap_slave) {
1603                 /* swap mac address */
1604                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1605         } else {
1606                 /* set the new_slave to the bond mac address */
1607                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1608                                        bond->alb_info.rlb_enabled);
1609         }
1610
1611         if (swap_slave) {
1612                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1613                 read_lock(&bond->lock);
1614         } else {
1615                 read_lock(&bond->lock);
1616                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1617         }
1618
1619         write_lock_bh(&bond->curr_slave_lock);
1620 }
1621
1622 /*
1623  * Called with RTNL
1624  */
1625 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1626         __acquires(&bond->lock)
1627         __releases(&bond->lock)
1628 {
1629         struct bonding *bond = netdev_priv(bond_dev);
1630         struct sockaddr *sa = addr;
1631         struct slave *slave, *swap_slave;
1632         int res;
1633         int i;
1634
1635         if (!is_valid_ether_addr(sa->sa_data)) {
1636                 return -EADDRNOTAVAIL;
1637         }
1638
1639         res = alb_set_mac_address(bond, addr);
1640         if (res) {
1641                 return res;
1642         }
1643
1644         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1645
1646         /* If there is no curr_active_slave there is nothing else to do.
1647          * Otherwise we'll need to pass the new address to it and handle
1648          * duplications.
1649          */
1650         if (!bond->curr_active_slave) {
1651                 return 0;
1652         }
1653
1654         swap_slave = NULL;
1655
1656         bond_for_each_slave(bond, slave, i) {
1657                 if (!compare_ether_addr_64bits(slave->dev->dev_addr,
1658                                                bond_dev->dev_addr)) {
1659                         swap_slave = slave;
1660                         break;
1661                 }
1662         }
1663
1664         if (swap_slave) {
1665                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1666                 alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1667         } else {
1668                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1669                                        bond->alb_info.rlb_enabled);
1670
1671                 read_lock(&bond->lock);
1672                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1673                 if (bond->alb_info.rlb_enabled) {
1674                         /* inform clients mac address has changed */
1675                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1676                 }
1677                 read_unlock(&bond->lock);
1678         }
1679
1680         return 0;
1681 }
1682
1683 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1684 {
1685         if (bond->alb_info.current_alb_vlan &&
1686             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1687                 bond->alb_info.current_alb_vlan = NULL;
1688         }
1689
1690         if (bond->alb_info.rlb_enabled) {
1691                 rlb_clear_vlan(bond, vlan_id);
1692         }
1693 }
1694