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 #include <linux/skbuff.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/etherdevice.h>
  26 #include <linux/pkt_sched.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/slab.h>
  29 #include <linux/timer.h>
  30 #include <linux/ip.h>
  31 #include <linux/ipv6.h>
  32 #include <linux/if_arp.h>
  33 #include <linux/if_ether.h>
  34 #include <linux/if_bonding.h>
  35 #include <linux/if_vlan.h>
  36 #include <linux/in.h>
  37 #include <net/ipx.h>
  38 #include <net/arp.h>
  39 #include <net/ipv6.h>
  40 #include <asm/byteorder.h>
  41 #include "bonding.h"
  42 #include "bond_alb.h"
  43
  44
  45 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
  46 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
  47                                          * Used for division - never set
  48                                          * to zero !!!
  49                                          */
  50 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
  51                                          * learning packets to the switch
  52                                          */
  53
  54 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
  55                                   * ALB_TIMER_TICKS_PER_SEC)
  56
  57 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
  58                            * ALB_TIMER_TICKS_PER_SEC)
  59
  60 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
  61                                  * Note that this value MUST NOT be smaller
  62                                  * because the key hash table is BYTE wide !
  63                                  */
  64
  65
  66 #define TLB_NULL_INDEX          0xffffffff
  67 #define MAX_LP_BURST            3
  68
  69 /* rlb defs */
  70 #define RLB_HASH_TABLE_SIZE     256
  71 #define RLB_NULL_INDEX          0xffffffff
  72 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
  73 #define RLB_ARP_BURST_SIZE      2
  74 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
  75                                          * rebalance interval (5 min).
  76                                          */
  77 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
  78  * promiscuous after failover
  79  */
  80 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
  81
  82 #ifndef __long_aligned
  83 #define __long_aligned __attribute__((aligned((sizeof(long)))))
  84 #endif
  85 static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
  86         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  87 };
  88 static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
  89         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  90 };
  91 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  92
  93 #pragma pack(1)
  94 struct learning_pkt {
  95         u8 mac_dst[ETH_ALEN];
  96         u8 mac_src[ETH_ALEN];
  97         __be16 type;
  98         u8 padding[ETH_ZLEN - ETH_HLEN];
  99 };
 100
 101 struct arp_pkt {
 102         __be16  hw_addr_space;
 103         __be16  prot_addr_space;
 104         u8      hw_addr_len;
 105         u8      prot_addr_len;
 106         __be16  op_code;
 107         u8      mac_src[ETH_ALEN];      /* sender hardware address */
 108         __be32  ip_src;                 /* sender IP address */
 109         u8      mac_dst[ETH_ALEN];      /* target hardware address */
 110         __be32  ip_dst;                 /* target IP address */
 111 };
 112 #pragma pack()
 113
 114 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
 115 {
 116         return (struct arp_pkt *)skb_network_header(skb);
 117 }
 118
 119 /* Forward declaration */
 120 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
 121
 122 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
 123 {
 124         int i;
 125         u8 hash = 0;
 126
 127         for (i = 0; i < hash_size; i++) {
 128                 hash ^= hash_start[i];
 129         }
 130
 131         return hash;
 132 }
 133
 134 /*********************** tlb specific functions ***************************/
 135
 136 static inline void _lock_tx_hashtbl(struct bonding *bond)
 137 {
 138         spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 139 }
 140
 141 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 142 {
 143         spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 144 }
 145
 146 /* Caller must hold tx_hashtbl lock */
 147 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 148 {
 149         if (save_load) {
 150                 entry->load_history = 1 + entry->tx_bytes /
 151                                       BOND_TLB_REBALANCE_INTERVAL;
 152                 entry->tx_bytes = 0;
 153         }
 154
 155         entry->tx_slave = NULL;
 156         entry->next = TLB_NULL_INDEX;
 157         entry->prev = TLB_NULL_INDEX;
 158 }
 159
 160 static inline void tlb_init_slave(struct slave *slave)
 161 {
 162         SLAVE_TLB_INFO(slave).load = 0;
 163         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 164 }
 165
 166 /* Caller must hold bond lock for read */
 167 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
 168 {
 169         struct tlb_client_info *tx_hash_table;
 170         u32 index;
 171
 172         _lock_tx_hashtbl(bond);
 173
 174         /* clear slave from tx_hashtbl */
 175         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 176
 177         /* skip this if we've already freed the tx hash table */
 178         if (tx_hash_table) {
 179                 index = SLAVE_TLB_INFO(slave).head;
 180                 while (index != TLB_NULL_INDEX) {
 181                         u32 next_index = tx_hash_table[index].next;
 182                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 183                         index = next_index;
 184                 }
 185         }
 186
 187         tlb_init_slave(slave);
 188
 189         _unlock_tx_hashtbl(bond);
 190 }
 191
 192 /* Must be called before starting the monitor timer */
 193 static int tlb_initialize(struct bonding *bond)
 194 {
 195         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 196         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 197         struct tlb_client_info *new_hashtbl;
 198         int i;
 199
 200         spin_lock_init(&(bond_info->tx_hashtbl_lock));
 201
 202         new_hashtbl = kzalloc(size, GFP_KERNEL);
 203         if (!new_hashtbl) {
 204                 pr_err(DRV_NAME
 205                        ": %s: Error: Failed to allocate TLB hash table\n",
 206                        bond->dev->name);
 207                 return -1;
 208         }
 209         _lock_tx_hashtbl(bond);
 210
 211         bond_info->tx_hashtbl = new_hashtbl;
 212
 213         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 214                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
 215         }
 216
 217         _unlock_tx_hashtbl(bond);
 218
 219         return 0;
 220 }
 221
 222 /* Must be called only after all slaves have been released */
 223 static void tlb_deinitialize(struct bonding *bond)
 224 {
 225         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 226
 227         _lock_tx_hashtbl(bond);
 228
 229         kfree(bond_info->tx_hashtbl);
 230         bond_info->tx_hashtbl = NULL;
 231
 232         _unlock_tx_hashtbl(bond);
 233 }
 234
 235 /* Caller must hold bond lock for read */
 236 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 237 {
 238         struct slave *slave, *least_loaded;
 239         s64 max_gap;
 240         int i, found = 0;
 241
 242         /* Find the first enabled slave */
 243         bond_for_each_slave(bond, slave, i) {
 244                 if (SLAVE_IS_OK(slave)) {
 245                         found = 1;
 246                         break;
 247                 }
 248         }
 249
 250         if (!found) {
 251                 return NULL;
 252         }
 253
 254         least_loaded = slave;
 255         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
 256                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 257
 258         /* Find the slave with the largest gap */
 259         bond_for_each_slave_from(bond, slave, i, least_loaded) {
 260                 if (SLAVE_IS_OK(slave)) {
 261                         s64 gap = (s64)(slave->speed << 20) -
 262                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
 263                         if (max_gap < gap) {
 264                                 least_loaded = slave;
 265                                 max_gap = gap;
 266                         }
 267                 }
 268         }
 269
 270         return least_loaded;
 271 }
 272
 273 /* Caller must hold bond lock for read */
 274 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
 275 {
 276         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 277         struct tlb_client_info *hash_table;
 278         struct slave *assigned_slave;
 279
 280         _lock_tx_hashtbl(bond);
 281
 282         hash_table = bond_info->tx_hashtbl;
 283         assigned_slave = hash_table[hash_index].tx_slave;
 284         if (!assigned_slave) {
 285                 assigned_slave = tlb_get_least_loaded_slave(bond);
 286
 287                 if (assigned_slave) {
 288                         struct tlb_slave_info *slave_info =
 289                                 &(SLAVE_TLB_INFO(assigned_slave));
 290                         u32 next_index = slave_info->head;
 291
 292                         hash_table[hash_index].tx_slave = assigned_slave;
 293                         hash_table[hash_index].next = next_index;
 294                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 295
 296                         if (next_index != TLB_NULL_INDEX) {
 297                                 hash_table[next_index].prev = hash_index;
 298                         }
 299
 300                         slave_info->head = hash_index;
 301                         slave_info->load +=
 302                                 hash_table[hash_index].load_history;
 303                 }
 304         }
 305
 306         if (assigned_slave) {
 307                 hash_table[hash_index].tx_bytes += skb_len;
 308         }
 309
 310         _unlock_tx_hashtbl(bond);
 311
 312         return assigned_slave;
 313 }
 314
 315 /*********************** rlb specific functions ***************************/
 316 static inline void _lock_rx_hashtbl(struct bonding *bond)
 317 {
 318         spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 319 }
 320
 321 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 322 {
 323         spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 324 }
 325
 326 /* when an ARP REPLY is received from a client update its info
 327  * in the rx_hashtbl
 328  */
 329 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 330 {
 331         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 332         struct rlb_client_info *client_info;
 333         u32 hash_index;
 334
 335         _lock_rx_hashtbl(bond);
 336
 337         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 338         client_info = &(bond_info->rx_hashtbl[hash_index]);
 339
 340         if ((client_info->assigned) &&
 341             (client_info->ip_src == arp->ip_dst) &&
 342             (client_info->ip_dst == arp->ip_src)) {
 343                 /* update the clients MAC address */
 344                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 345                 client_info->ntt = 1;
 346                 bond_info->rx_ntt = 1;
 347         }
 348
 349         _unlock_rx_hashtbl(bond);
 350 }
 351
 352 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype, struct net_device *orig_dev)
 353 {
 354         struct bonding *bond;
 355         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
 356         int res = NET_RX_DROP;
 357
 358         if (dev_net(bond_dev) != &init_net)
 359                 goto out;
 360
 361         while (bond_dev->priv_flags & IFF_802_1Q_VLAN)
 362                 bond_dev = vlan_dev_real_dev(bond_dev);
 363
 364         if (!(bond_dev->priv_flags & IFF_BONDING) ||
 365             !(bond_dev->flags & IFF_MASTER))
 366                 goto out;
 367
 368         if (!arp) {
 369                 pr_debug("Packet has no ARP data\n");
 370                 goto out;
 371         }
 372
 373         if (skb->len < sizeof(struct arp_pkt)) {
 374                 pr_debug("Packet is too small to be an ARP\n");
 375                 goto out;
 376         }
 377
 378         if (arp->op_code == htons(ARPOP_REPLY)) {
 379                 /* update rx hash table for this ARP */
 380                 bond = netdev_priv(bond_dev);
 381                 rlb_update_entry_from_arp(bond, arp);
 382                 pr_debug("Server received an ARP Reply from client\n");
 383         }
 384
 385         res = NET_RX_SUCCESS;
 386
 387 out:
 388         dev_kfree_skb(skb);
 389
 390         return res;
 391 }
 392
 393 /* Caller must hold bond lock for read */
 394 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 395 {
 396         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 397         struct slave *rx_slave, *slave, *start_at;
 398         int i = 0;
 399
 400         if (bond_info->next_rx_slave) {
 401                 start_at = bond_info->next_rx_slave;
 402         } else {
 403                 start_at = bond->first_slave;
 404         }
 405
 406         rx_slave = NULL;
 407
 408         bond_for_each_slave_from(bond, slave, i, start_at) {
 409                 if (SLAVE_IS_OK(slave)) {
 410                         if (!rx_slave) {
 411                                 rx_slave = slave;
 412                         } else if (slave->speed > rx_slave->speed) {
 413                                 rx_slave = slave;
 414                         }
 415                 }
 416         }
 417
 418         if (rx_slave) {
 419                 bond_info->next_rx_slave = rx_slave->next;
 420         }
 421
 422         return rx_slave;
 423 }
 424
 425 /* teach the switch the mac of a disabled slave
 426  * on the primary for fault tolerance
 427  *
 428  * Caller must hold bond->curr_slave_lock for write or bond lock for write
 429  */
 430 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 431 {
 432         if (!bond->curr_active_slave) {
 433                 return;
 434         }
 435
 436         if (!bond->alb_info.primary_is_promisc) {
 437                 if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
 438                         bond->alb_info.primary_is_promisc = 1;
 439                 else
 440                         bond->alb_info.primary_is_promisc = 0;
 441         }
 442
 443         bond->alb_info.rlb_promisc_timeout_counter = 0;
 444
 445         alb_send_learning_packets(bond->curr_active_slave, addr);
 446 }
 447
 448 /* slave being removed should not be active at this point
 449  *
 450  * Caller must hold bond lock for read
 451  */
 452 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 453 {
 454         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 455         struct rlb_client_info *rx_hash_table;
 456         u32 index, next_index;
 457
 458         /* clear slave from rx_hashtbl */
 459         _lock_rx_hashtbl(bond);
 460
 461         rx_hash_table = bond_info->rx_hashtbl;
 462         index = bond_info->rx_hashtbl_head;
 463         for (; index != RLB_NULL_INDEX; index = next_index) {
 464                 next_index = rx_hash_table[index].next;
 465                 if (rx_hash_table[index].slave == slave) {
 466                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 467
 468                         if (assigned_slave) {
 469                                 rx_hash_table[index].slave = assigned_slave;
 470                                 if (compare_ether_addr_64bits(rx_hash_table[index].mac_dst,
 471                                                               mac_bcast)) {
 472                                         bond_info->rx_hashtbl[index].ntt = 1;
 473                                         bond_info->rx_ntt = 1;
 474                                         /* A slave has been removed from the
 475                                          * table because it is either disabled
 476                                          * or being released. We must retry the
 477                                          * update to avoid clients from not
 478                                          * being updated & disconnecting when
 479                                          * there is stress
 480                                          */
 481                                         bond_info->rlb_update_retry_counter =
 482                                                 RLB_UPDATE_RETRY;
 483                                 }
 484                         } else {  /* there is no active slave */
 485                                 rx_hash_table[index].slave = NULL;
 486                         }
 487                 }
 488         }
 489
 490         _unlock_rx_hashtbl(bond);
 491
 492         write_lock_bh(&bond->curr_slave_lock);
 493
 494         if (slave != bond->curr_active_slave) {
 495                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 496         }
 497
 498         write_unlock_bh(&bond->curr_slave_lock);
 499 }
 500
 501 static void rlb_update_client(struct rlb_client_info *client_info)
 502 {
 503         int i;
 504
 505         if (!client_info->slave) {
 506                 return;
 507         }
 508
 509         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 510                 struct sk_buff *skb;
 511
 512                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 513                                  client_info->ip_dst,
 514                                  client_info->slave->dev,
 515                                  client_info->ip_src,
 516                                  client_info->mac_dst,
 517                                  client_info->slave->dev->dev_addr,
 518                                  client_info->mac_dst);
 519                 if (!skb) {
 520                         pr_err(DRV_NAME
 521                                ": %s: Error: failed to create an ARP packet\n",
 522                                client_info->slave->dev->master->name);
 523                         continue;
 524                 }
 525
 526                 skb->dev = client_info->slave->dev;
 527
 528                 if (client_info->tag) {
 529                         skb = vlan_put_tag(skb, client_info->vlan_id);
 530                         if (!skb) {
 531                                 pr_err(DRV_NAME
 532                                        ": %s: Error: failed to insert VLAN tag\n",
 533                                        client_info->slave->dev->master->name);
 534                                 continue;
 535                         }
 536                 }
 537
 538                 arp_xmit(skb);
 539         }
 540 }
 541
 542 /* sends ARP REPLIES that update the clients that need updating */
 543 static void rlb_update_rx_clients(struct bonding *bond)
 544 {
 545         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 546         struct rlb_client_info *client_info;
 547         u32 hash_index;
 548
 549         _lock_rx_hashtbl(bond);
 550
 551         hash_index = bond_info->rx_hashtbl_head;
 552         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 553                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 554                 if (client_info->ntt) {
 555                         rlb_update_client(client_info);
 556                         if (bond_info->rlb_update_retry_counter == 0) {
 557                                 client_info->ntt = 0;
 558                         }
 559                 }
 560         }
 561
 562         /* do not update the entries again until this counter is zero so that
 563          * not to confuse the clients.
 564          */
 565         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 566
 567         _unlock_rx_hashtbl(bond);
 568 }
 569
 570 /* The slave was assigned a new mac address - update the clients */
 571 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 572 {
 573         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 574         struct rlb_client_info *client_info;
 575         int ntt = 0;
 576         u32 hash_index;
 577
 578         _lock_rx_hashtbl(bond);
 579
 580         hash_index = bond_info->rx_hashtbl_head;
 581         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 582                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 583
 584                 if ((client_info->slave == slave) &&
 585                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 586                         client_info->ntt = 1;
 587                         ntt = 1;
 588                 }
 589         }
 590
 591         // update the team's flag only after the whole iteration
 592         if (ntt) {
 593                 bond_info->rx_ntt = 1;
 594                 //fasten the change
 595                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 596         }
 597
 598         _unlock_rx_hashtbl(bond);
 599 }
 600
 601 /* mark all clients using src_ip to be updated */
 602 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 603 {
 604         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 605         struct rlb_client_info *client_info;
 606         u32 hash_index;
 607
 608         _lock_rx_hashtbl(bond);
 609
 610         hash_index = bond_info->rx_hashtbl_head;
 611         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 612                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 613
 614                 if (!client_info->slave) {
 615                         pr_err(DRV_NAME
 616                                ": %s: Error: found a client with no channel in "
 617                                "the client's hash table\n",
 618                                bond->dev->name);
 619                         continue;
 620                 }
 621                 /*update all clients using this src_ip, that are not assigned
 622                  * to the team's address (curr_active_slave) and have a known
 623                  * unicast mac address.
 624                  */
 625                 if ((client_info->ip_src == src_ip) &&
 626                     compare_ether_addr_64bits(client_info->slave->dev->dev_addr,
 627                            bond->dev->dev_addr) &&
 628                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 629                         client_info->ntt = 1;
 630                         bond_info->rx_ntt = 1;
 631                 }
 632         }
 633
 634         _unlock_rx_hashtbl(bond);
 635 }
 636
 637 /* Caller must hold both bond and ptr locks for read */
 638 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 639 {
 640         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 641         struct arp_pkt *arp = arp_pkt(skb);
 642         struct slave *assigned_slave;
 643         struct rlb_client_info *client_info;
 644         u32 hash_index = 0;
 645
 646         _lock_rx_hashtbl(bond);
 647
 648         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_src));
 649         client_info = &(bond_info->rx_hashtbl[hash_index]);
 650
 651         if (client_info->assigned) {
 652                 if ((client_info->ip_src == arp->ip_src) &&
 653                     (client_info->ip_dst == arp->ip_dst)) {
 654                         /* the entry is already assigned to this client */
 655                         if (compare_ether_addr_64bits(arp->mac_dst, mac_bcast)) {
 656                                 /* update mac address from arp */
 657                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 658                         }
 659
 660                         assigned_slave = client_info->slave;
 661                         if (assigned_slave) {
 662                                 _unlock_rx_hashtbl(bond);
 663                                 return assigned_slave;
 664                         }
 665                 } else {
 666                         /* the entry is already assigned to some other client,
 667                          * move the old client to primary (curr_active_slave) so
 668                          * that the new client can be assigned to this entry.
 669                          */
 670                         if (bond->curr_active_slave &&
 671                             client_info->slave != bond->curr_active_slave) {
 672                                 client_info->slave = bond->curr_active_slave;
 673                                 rlb_update_client(client_info);
 674                         }
 675                 }
 676         }
 677         /* assign a new slave */
 678         assigned_slave = rlb_next_rx_slave(bond);
 679
 680         if (assigned_slave) {
 681                 client_info->ip_src = arp->ip_src;
 682                 client_info->ip_dst = arp->ip_dst;
 683                 /* arp->mac_dst is broadcast for arp reqeusts.
 684                  * will be updated with clients actual unicast mac address
 685                  * upon receiving an arp reply.
 686                  */
 687                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 688                 client_info->slave = assigned_slave;
 689
 690                 if (compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 691                         client_info->ntt = 1;
 692                         bond->alb_info.rx_ntt = 1;
 693                 } else {
 694                         client_info->ntt = 0;
 695                 }
 696
 697                 if (!list_empty(&bond->vlan_list)) {
 698                         if (!vlan_get_tag(skb, &client_info->vlan_id))
 699                                 client_info->tag = 1;
 700                 }
 701
 702                 if (!client_info->assigned) {
 703                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
 704                         bond_info->rx_hashtbl_head = hash_index;
 705                         client_info->next = prev_tbl_head;
 706                         if (prev_tbl_head != RLB_NULL_INDEX) {
 707                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
 708                                         hash_index;
 709                         }
 710                         client_info->assigned = 1;
 711                 }
 712         }
 713
 714         _unlock_rx_hashtbl(bond);
 715
 716         return assigned_slave;
 717 }
 718
 719 /* chooses (and returns) transmit channel for arp reply
 720  * does not choose channel for other arp types since they are
 721  * sent on the curr_active_slave
 722  */
 723 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 724 {
 725         struct arp_pkt *arp = arp_pkt(skb);
 726         struct slave *tx_slave = NULL;
 727
 728         if (arp->op_code == htons(ARPOP_REPLY)) {
 729                 /* the arp must be sent on the selected
 730                 * rx channel
 731                 */
 732                 tx_slave = rlb_choose_channel(skb, bond);
 733                 if (tx_slave) {
 734                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
 735                 }
 736                 pr_debug("Server sent ARP Reply packet\n");
 737         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 738                 /* Create an entry in the rx_hashtbl for this client as a
 739                  * place holder.
 740                  * When the arp reply is received the entry will be updated
 741                  * with the correct unicast address of the client.
 742                  */
 743                 rlb_choose_channel(skb, bond);
 744
 745                 /* The ARP relpy packets must be delayed so that
 746                  * they can cancel out the influence of the ARP request.
 747                  */
 748                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 749
 750                 /* arp requests are broadcast and are sent on the primary
 751                  * the arp request will collapse all clients on the subnet to
 752                  * the primary slave. We must register these clients to be
 753                  * updated with their assigned mac.
 754                  */
 755                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 756                 pr_debug("Server sent ARP Request packet\n");
 757         }
 758
 759         return tx_slave;
 760 }
 761
 762 /* Caller must hold bond lock for read */
 763 static void rlb_rebalance(struct bonding *bond)
 764 {
 765         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 766         struct slave *assigned_slave;
 767         struct rlb_client_info *client_info;
 768         int ntt;
 769         u32 hash_index;
 770
 771         _lock_rx_hashtbl(bond);
 772
 773         ntt = 0;
 774         hash_index = bond_info->rx_hashtbl_head;
 775         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 776                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 777                 assigned_slave = rlb_next_rx_slave(bond);
 778                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 779                         client_info->slave = assigned_slave;
 780                         client_info->ntt = 1;
 781                         ntt = 1;
 782                 }
 783         }
 784
 785         /* update the team's flag only after the whole iteration */
 786         if (ntt) {
 787                 bond_info->rx_ntt = 1;
 788         }
 789         _unlock_rx_hashtbl(bond);
 790 }
 791
 792 /* Caller must hold rx_hashtbl lock */
 793 static void rlb_init_table_entry(struct rlb_client_info *entry)
 794 {
 795         memset(entry, 0, sizeof(struct rlb_client_info));
 796         entry->next = RLB_NULL_INDEX;
 797         entry->prev = RLB_NULL_INDEX;
 798 }
 799
 800 static int rlb_initialize(struct bonding *bond)
 801 {
 802         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 803         struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
 804         struct rlb_client_info  *new_hashtbl;
 805         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 806         int i;
 807
 808         spin_lock_init(&(bond_info->rx_hashtbl_lock));
 809
 810         new_hashtbl = kmalloc(size, GFP_KERNEL);
 811         if (!new_hashtbl) {
 812                 pr_err(DRV_NAME
 813                        ": %s: Error: Failed to allocate RLB hash table\n",
 814                        bond->dev->name);
 815                 return -1;
 816         }
 817         _lock_rx_hashtbl(bond);
 818
 819         bond_info->rx_hashtbl = new_hashtbl;
 820
 821         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 822
 823         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
 824                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 825         }
 826
 827         _unlock_rx_hashtbl(bond);
 828
 829         /*initialize packet type*/
 830         pk_type->type = cpu_to_be16(ETH_P_ARP);
 831         pk_type->dev = NULL;
 832         pk_type->func = rlb_arp_recv;
 833
 834         /* register to receive ARPs */
 835         dev_add_pack(pk_type);
 836
 837         return 0;
 838 }
 839
 840 static void rlb_deinitialize(struct bonding *bond)
 841 {
 842         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 843
 844         dev_remove_pack(&(bond_info->rlb_pkt_type));
 845
 846         _lock_rx_hashtbl(bond);
 847
 848         kfree(bond_info->rx_hashtbl);
 849         bond_info->rx_hashtbl = NULL;
 850         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 851
 852         _unlock_rx_hashtbl(bond);
 853 }
 854
 855 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 856 {
 857         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 858         u32 curr_index;
 859
 860         _lock_rx_hashtbl(bond);
 861
 862         curr_index = bond_info->rx_hashtbl_head;
 863         while (curr_index != RLB_NULL_INDEX) {
 864                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 865                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
 866                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
 867
 868                 if (curr->tag && (curr->vlan_id == vlan_id)) {
 869                         if (curr_index == bond_info->rx_hashtbl_head) {
 870                                 bond_info->rx_hashtbl_head = next_index;
 871                         }
 872                         if (prev_index != RLB_NULL_INDEX) {
 873                                 bond_info->rx_hashtbl[prev_index].next = next_index;
 874                         }
 875                         if (next_index != RLB_NULL_INDEX) {
 876                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
 877                         }
 878
 879                         rlb_init_table_entry(curr);
 880                 }
 881
 882                 curr_index = next_index;
 883         }
 884
 885         _unlock_rx_hashtbl(bond);
 886 }
 887
 888 /*********************** tlb/rlb shared functions *********************/
 889
 890 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
 891 {
 892         struct bonding *bond = bond_get_bond_by_slave(slave);
 893         struct learning_pkt pkt;
 894         int size = sizeof(struct learning_pkt);
 895         int i;
 896
 897         memset(&pkt, 0, size);
 898         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
 899         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
 900         pkt.type = cpu_to_be16(ETH_P_LOOP);
 901
 902         for (i = 0; i < MAX_LP_BURST; i++) {
 903                 struct sk_buff *skb;
 904                 char *data;
 905
 906                 skb = dev_alloc_skb(size);
 907                 if (!skb) {
 908                         return;
 909                 }
 910
 911                 data = skb_put(skb, size);
 912                 memcpy(data, &pkt, size);
 913
 914                 skb_reset_mac_header(skb);
 915                 skb->network_header = skb->mac_header + ETH_HLEN;
 916                 skb->protocol = pkt.type;
 917                 skb->priority = TC_PRIO_CONTROL;
 918                 skb->dev = slave->dev;
 919
 920                 if (!list_empty(&bond->vlan_list)) {
 921                         struct vlan_entry *vlan;
 922
 923                         vlan = bond_next_vlan(bond,
 924                                               bond->alb_info.current_alb_vlan);
 925
 926                         bond->alb_info.current_alb_vlan = vlan;
 927                         if (!vlan) {
 928                                 kfree_skb(skb);
 929                                 continue;
 930                         }
 931
 932                         skb = vlan_put_tag(skb, vlan->vlan_id);
 933                         if (!skb) {
 934                                 pr_err(DRV_NAME
 935                                        ": %s: Error: failed to insert VLAN tag\n",
 936                                        bond->dev->name);
 937                                 continue;
 938                         }
 939                 }
 940
 941                 dev_queue_xmit(skb);
 942         }
 943 }
 944
 945 /* hw is a boolean parameter that determines whether we should try and
 946  * set the hw address of the device as well as the hw address of the
 947  * net_device
 948  */
 949 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
 950 {
 951         struct net_device *dev = slave->dev;
 952         struct sockaddr s_addr;
 953
 954         if (!hw) {
 955                 memcpy(dev->dev_addr, addr, dev->addr_len);
 956                 return 0;
 957         }
 958
 959         /* for rlb each slave must have a unique hw mac addresses so that */
 960         /* each slave will receive packets destined to a different mac */
 961         memcpy(s_addr.sa_data, addr, dev->addr_len);
 962         s_addr.sa_family = dev->type;
 963         if (dev_set_mac_address(dev, &s_addr)) {
 964                 pr_err(DRV_NAME
 965                        ": %s: Error: dev_set_mac_address of dev %s failed! ALB "
 966                        "mode requires that the base driver support setting "
 967                        "the hw address also when the network device's "
 968                        "interface is open\n",
 969                        dev->master->name, dev->name);
 970                 return -EOPNOTSUPP;
 971         }
 972         return 0;
 973 }
 974
 975 /*
 976  * Swap MAC addresses between two slaves.
 977  *
 978  * Called with RTNL held, and no other locks.
 979  *
 980  */
 981
 982 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
 983 {
 984         u8 tmp_mac_addr[ETH_ALEN];
 985
 986         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
 987         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
 988         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
 989
 990 }
 991
 992 /*
 993  * Send learning packets after MAC address swap.
 994  *
 995  * Called with RTNL and no other locks
 996  */
 997 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
 998                                 struct slave *slave2)
 999 {
1000         int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
1001         struct slave *disabled_slave = NULL;
1002
1003         ASSERT_RTNL();
1004
1005         /* fasten the change in the switch */
1006         if (SLAVE_IS_OK(slave1)) {
1007                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
1008                 if (bond->alb_info.rlb_enabled) {
1009                         /* inform the clients that the mac address
1010                          * has changed
1011                          */
1012                         rlb_req_update_slave_clients(bond, slave1);
1013                 }
1014         } else {
1015                 disabled_slave = slave1;
1016         }
1017
1018         if (SLAVE_IS_OK(slave2)) {
1019                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
1020                 if (bond->alb_info.rlb_enabled) {
1021                         /* inform the clients that the mac address
1022                          * has changed
1023                          */
1024                         rlb_req_update_slave_clients(bond, slave2);
1025                 }
1026         } else {
1027                 disabled_slave = slave2;
1028         }
1029
1030         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1031                 /* A disabled slave was assigned an active mac addr */
1032                 rlb_teach_disabled_mac_on_primary(bond,
1033                                                   disabled_slave->dev->dev_addr);
1034         }
1035 }
1036
1037 /**
1038  * alb_change_hw_addr_on_detach
1039  * @bond: bonding we're working on
1040  * @slave: the slave that was just detached
1041  *
1042  * We assume that @slave was already detached from the slave list.
1043  *
1044  * If @slave's permanent hw address is different both from its current
1045  * address and from @bond's address, then somewhere in the bond there's
1046  * a slave that has @slave's permanet address as its current address.
1047  * We'll make sure that that slave no longer uses @slave's permanent address.
1048  *
1049  * Caller must hold RTNL and no other locks
1050  */
1051 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1052 {
1053         int perm_curr_diff;
1054         int perm_bond_diff;
1055
1056         perm_curr_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1057                                                    slave->dev->dev_addr);
1058         perm_bond_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1059                                                    bond->dev->dev_addr);
1060
1061         if (perm_curr_diff && perm_bond_diff) {
1062                 struct slave *tmp_slave;
1063                 int i, found = 0;
1064
1065                 bond_for_each_slave(bond, tmp_slave, i) {
1066                         if (!compare_ether_addr_64bits(slave->perm_hwaddr,
1067                                                        tmp_slave->dev->dev_addr)) {
1068                                 found = 1;
1069                                 break;
1070                         }
1071                 }
1072
1073                 if (found) {
1074                         /* locking: needs RTNL and nothing else */
1075                         alb_swap_mac_addr(bond, slave, tmp_slave);
1076                         alb_fasten_mac_swap(bond, slave, tmp_slave);
1077                 }
1078         }
1079 }
1080
1081 /**
1082  * alb_handle_addr_collision_on_attach
1083  * @bond: bonding we're working on
1084  * @slave: the slave that was just attached
1085  *
1086  * checks uniqueness of slave's mac address and handles the case the
1087  * new slave uses the bonds mac address.
1088  *
1089  * If the permanent hw address of @slave is @bond's hw address, we need to
1090  * find a different hw address to give @slave, that isn't in use by any other
1091  * slave in the bond. This address must be, of course, one of the premanent
1092  * addresses of the other slaves.
1093  *
1094  * We go over the slave list, and for each slave there we compare its
1095  * permanent hw address with the current address of all the other slaves.
1096  * If no match was found, then we've found a slave with a permanent address
1097  * that isn't used by any other slave in the bond, so we can assign it to
1098  * @slave.
1099  *
1100  * assumption: this function is called before @slave is attached to the
1101  *             bond slave list.
1102  *
1103  * caller must hold the bond lock for write since the mac addresses are compared
1104  * and may be swapped.
1105  */
1106 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1107 {
1108         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1109         struct slave *has_bond_addr = bond->curr_active_slave;
1110         int i, j, found = 0;
1111
1112         if (bond->slave_cnt == 0) {
1113                 /* this is the first slave */
1114                 return 0;
1115         }
1116
1117         /* if slave's mac address differs from bond's mac address
1118          * check uniqueness of slave's mac address against the other
1119          * slaves in the bond.
1120          */
1121         if (compare_ether_addr_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1122                 bond_for_each_slave(bond, tmp_slave1, i) {
1123                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1124                                                        slave->dev->dev_addr)) {
1125                                 found = 1;
1126                                 break;
1127                         }
1128                 }
1129
1130                 if (!found)
1131                         return 0;
1132
1133                 /* Try setting slave mac to bond address and fall-through
1134                    to code handling that situation below... */
1135                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1136                                        bond->alb_info.rlb_enabled);
1137         }
1138
1139         /* The slave's address is equal to the address of the bond.
1140          * Search for a spare address in the bond for this slave.
1141          */
1142         free_mac_slave = NULL;
1143
1144         bond_for_each_slave(bond, tmp_slave1, i) {
1145                 found = 0;
1146                 bond_for_each_slave(bond, tmp_slave2, j) {
1147                         if (!compare_ether_addr_64bits(tmp_slave1->perm_hwaddr,
1148                                                        tmp_slave2->dev->dev_addr)) {
1149                                 found = 1;
1150                                 break;
1151                         }
1152                 }
1153
1154                 if (!found) {
1155                         /* no slave has tmp_slave1's perm addr
1156                          * as its curr addr
1157                          */
1158                         free_mac_slave = tmp_slave1;
1159                         break;
1160                 }
1161
1162                 if (!has_bond_addr) {
1163                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1164                                                        bond->dev->dev_addr)) {
1165
1166                                 has_bond_addr = tmp_slave1;
1167                         }
1168                 }
1169         }
1170
1171         if (free_mac_slave) {
1172                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1173                                        bond->alb_info.rlb_enabled);
1174
1175                 pr_warning(DRV_NAME
1176                            ": %s: Warning: the hw address of slave %s is "
1177                            "in use by the bond; giving it the hw address "
1178                            "of %s\n",
1179                            bond->dev->name, slave->dev->name,
1180                            free_mac_slave->dev->name);
1181
1182         } else if (has_bond_addr) {
1183                 pr_err(DRV_NAME
1184                        ": %s: Error: the hw address of slave %s is in use by the "
1185                        "bond; couldn't find a slave with a free hw address to "
1186                        "give it (this should not have happened)\n",
1187                        bond->dev->name, slave->dev->name);
1188                 return -EFAULT;
1189         }
1190
1191         return 0;
1192 }
1193
1194 /**
1195  * alb_set_mac_address
1196  * @bond:
1197  * @addr:
1198  *
1199  * In TLB mode all slaves are configured to the bond's hw address, but set
1200  * their dev_addr field to different addresses (based on their permanent hw
1201  * addresses).
1202  *
1203  * For each slave, this function sets the interface to the new address and then
1204  * changes its dev_addr field to its previous value.
1205  *
1206  * Unwinding assumes bond's mac address has not yet changed.
1207  */
1208 static int alb_set_mac_address(struct bonding *bond, void *addr)
1209 {
1210         struct sockaddr sa;
1211         struct slave *slave, *stop_at;
1212         char tmp_addr[ETH_ALEN];
1213         int res;
1214         int i;
1215
1216         if (bond->alb_info.rlb_enabled) {
1217                 return 0;
1218         }
1219
1220         bond_for_each_slave(bond, slave, i) {
1221                 /* save net_device's current hw address */
1222                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1223
1224                 res = dev_set_mac_address(slave->dev, addr);
1225
1226                 /* restore net_device's hw address */
1227                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1228
1229                 if (res)
1230                         goto unwind;
1231         }
1232
1233         return 0;
1234
1235 unwind:
1236         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1237         sa.sa_family = bond->dev->type;
1238
1239         /* unwind from head to the slave that failed */
1240         stop_at = slave;
1241         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1242                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1243                 dev_set_mac_address(slave->dev, &sa);
1244                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1245         }
1246
1247         return res;
1248 }
1249
1250 /************************ exported alb funcions ************************/
1251
1252 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1253 {
1254         int res;
1255
1256         res = tlb_initialize(bond);
1257         if (res) {
1258                 return res;
1259         }
1260
1261         if (rlb_enabled) {
1262                 bond->alb_info.rlb_enabled = 1;
1263                 /* initialize rlb */
1264                 res = rlb_initialize(bond);
1265                 if (res) {
1266                         tlb_deinitialize(bond);
1267                         return res;
1268                 }
1269         } else {
1270                 bond->alb_info.rlb_enabled = 0;
1271         }
1272
1273         return 0;
1274 }
1275
1276 void bond_alb_deinitialize(struct bonding *bond)
1277 {
1278         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1279
1280         tlb_deinitialize(bond);
1281
1282         if (bond_info->rlb_enabled) {
1283                 rlb_deinitialize(bond);
1284         }
1285 }
1286
1287 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1288 {
1289         struct bonding *bond = netdev_priv(bond_dev);
1290         struct ethhdr *eth_data;
1291         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1292         struct slave *tx_slave = NULL;
1293         static const __be32 ip_bcast = htonl(0xffffffff);
1294         int hash_size = 0;
1295         int do_tx_balance = 1;
1296         u32 hash_index = 0;
1297         const u8 *hash_start = NULL;
1298         int res = 1;
1299         struct ipv6hdr *ip6hdr;
1300
1301         skb_reset_mac_header(skb);
1302         eth_data = eth_hdr(skb);
1303
1304         /* make sure that the curr_active_slave and the slaves list do
1305          * not change during tx
1306          */
1307         read_lock(&bond->lock);
1308         read_lock(&bond->curr_slave_lock);
1309
1310         if (!BOND_IS_OK(bond)) {
1311                 goto out;
1312         }
1313
1314         switch (ntohs(skb->protocol)) {
1315         case ETH_P_IP: {
1316                 const struct iphdr *iph = ip_hdr(skb);
1317
1318                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast) ||
1319                     (iph->daddr == ip_bcast) ||
1320                     (iph->protocol == IPPROTO_IGMP)) {
1321                         do_tx_balance = 0;
1322                         break;
1323                 }
1324                 hash_start = (char *)&(iph->daddr);
1325                 hash_size = sizeof(iph->daddr);
1326         }
1327                 break;
1328         case ETH_P_IPV6:
1329                 /* IPv6 doesn't really use broadcast mac address, but leave
1330                  * that here just in case.
1331                  */
1332                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast)) {
1333                         do_tx_balance = 0;
1334                         break;
1335                 }
1336
1337                 /* IPv6 uses all-nodes multicast as an equivalent to
1338                  * broadcasts in IPv4.
1339                  */
1340                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1341                         do_tx_balance = 0;
1342                         break;
1343                 }
1344
1345                 /* Additianally, DAD probes should not be tx-balanced as that
1346                  * will lead to false positives for duplicate addresses and
1347                  * prevent address configuration from working.
1348                  */
1349                 ip6hdr = ipv6_hdr(skb);
1350                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1351                         do_tx_balance = 0;
1352                         break;
1353                 }
1354
1355                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1356                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1357                 break;
1358         case ETH_P_IPX:
1359                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1360                         /* something is wrong with this packet */
1361                         do_tx_balance = 0;
1362                         break;
1363                 }
1364
1365                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1366                         /* The only protocol worth balancing in
1367                          * this family since it has an "ARP" like
1368                          * mechanism
1369                          */
1370                         do_tx_balance = 0;
1371                         break;
1372                 }
1373
1374                 hash_start = (char*)eth_data->h_dest;
1375                 hash_size = ETH_ALEN;
1376                 break;
1377         case ETH_P_ARP:
1378                 do_tx_balance = 0;
1379                 if (bond_info->rlb_enabled) {
1380                         tx_slave = rlb_arp_xmit(skb, bond);
1381                 }
1382                 break;
1383         default:
1384                 do_tx_balance = 0;
1385                 break;
1386         }
1387
1388         if (do_tx_balance) {
1389                 hash_index = _simple_hash(hash_start, hash_size);
1390                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1391         }
1392
1393         if (!tx_slave) {
1394                 /* unbalanced or unassigned, send through primary */
1395                 tx_slave = bond->curr_active_slave;
1396                 bond_info->unbalanced_load += skb->len;
1397         }
1398
1399         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1400                 if (tx_slave != bond->curr_active_slave) {
1401                         memcpy(eth_data->h_source,
1402                                tx_slave->dev->dev_addr,
1403                                ETH_ALEN);
1404                 }
1405
1406                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1407         } else {
1408                 if (tx_slave) {
1409                         tlb_clear_slave(bond, tx_slave, 0);
1410                 }
1411         }
1412
1413 out:
1414         if (res) {
1415                 /* no suitable interface, frame not sent */
1416                 dev_kfree_skb(skb);
1417         }
1418         read_unlock(&bond->curr_slave_lock);
1419         read_unlock(&bond->lock);
1420         return NETDEV_TX_OK;
1421 }
1422
1423 void bond_alb_monitor(struct work_struct *work)
1424 {
1425         struct bonding *bond = container_of(work, struct bonding,
1426                                             alb_work.work);
1427         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1428         struct slave *slave;
1429         int i;
1430
1431         read_lock(&bond->lock);
1432
1433         if (bond->kill_timers) {
1434                 goto out;
1435         }
1436
1437         if (bond->slave_cnt == 0) {
1438                 bond_info->tx_rebalance_counter = 0;
1439                 bond_info->lp_counter = 0;
1440                 goto re_arm;
1441         }
1442
1443         bond_info->tx_rebalance_counter++;
1444         bond_info->lp_counter++;
1445
1446         /* send learning packets */
1447         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1448                 /* change of curr_active_slave involves swapping of mac addresses.
1449                  * in order to avoid this swapping from happening while
1450                  * sending the learning packets, the curr_slave_lock must be held for
1451                  * read.
1452                  */
1453                 read_lock(&bond->curr_slave_lock);
1454
1455                 bond_for_each_slave(bond, slave, i) {
1456                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1457                 }
1458
1459                 read_unlock(&bond->curr_slave_lock);
1460
1461                 bond_info->lp_counter = 0;
1462         }
1463
1464         /* rebalance tx traffic */
1465         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1466
1467                 read_lock(&bond->curr_slave_lock);
1468
1469                 bond_for_each_slave(bond, slave, i) {
1470                         tlb_clear_slave(bond, slave, 1);
1471                         if (slave == bond->curr_active_slave) {
1472                                 SLAVE_TLB_INFO(slave).load =
1473                                         bond_info->unbalanced_load /
1474                                                 BOND_TLB_REBALANCE_INTERVAL;
1475                                 bond_info->unbalanced_load = 0;
1476                         }
1477                 }
1478
1479                 read_unlock(&bond->curr_slave_lock);
1480
1481                 bond_info->tx_rebalance_counter = 0;
1482         }
1483
1484         /* handle rlb stuff */
1485         if (bond_info->rlb_enabled) {
1486                 if (bond_info->primary_is_promisc &&
1487                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1488
1489                         /*
1490                          * dev_set_promiscuity requires rtnl and
1491                          * nothing else.
1492                          */
1493                         read_unlock(&bond->lock);
1494                         rtnl_lock();
1495
1496                         bond_info->rlb_promisc_timeout_counter = 0;
1497
1498                         /* If the primary was set to promiscuous mode
1499                          * because a slave was disabled then
1500                          * it can now leave promiscuous mode.
1501                          */
1502                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1503                         bond_info->primary_is_promisc = 0;
1504
1505                         rtnl_unlock();
1506                         read_lock(&bond->lock);
1507                 }
1508
1509                 if (bond_info->rlb_rebalance) {
1510                         bond_info->rlb_rebalance = 0;
1511                         rlb_rebalance(bond);
1512                 }
1513
1514                 /* check if clients need updating */
1515                 if (bond_info->rx_ntt) {
1516                         if (bond_info->rlb_update_delay_counter) {
1517                                 --bond_info->rlb_update_delay_counter;
1518                         } else {
1519                                 rlb_update_rx_clients(bond);
1520                                 if (bond_info->rlb_update_retry_counter) {
1521                                         --bond_info->rlb_update_retry_counter;
1522                                 } else {
1523                                         bond_info->rx_ntt = 0;
1524                                 }
1525                         }
1526                 }
1527         }
1528
1529 re_arm:
1530         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1531 out:
1532         read_unlock(&bond->lock);
1533 }
1534
1535 /* assumption: called before the slave is attached to the bond
1536  * and not locked by the bond lock
1537  */
1538 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1539 {
1540         int res;
1541
1542         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1543                                      bond->alb_info.rlb_enabled);
1544         if (res) {
1545                 return res;
1546         }
1547
1548         /* caller must hold the bond lock for write since the mac addresses
1549          * are compared and may be swapped.
1550          */
1551         read_lock(&bond->lock);
1552
1553         res = alb_handle_addr_collision_on_attach(bond, slave);
1554
1555         read_unlock(&bond->lock);
1556
1557         if (res) {
1558                 return res;
1559         }
1560
1561         tlb_init_slave(slave);
1562
1563         /* order a rebalance ASAP */
1564         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1565
1566         if (bond->alb_info.rlb_enabled) {
1567                 bond->alb_info.rlb_rebalance = 1;
1568         }
1569
1570         return 0;
1571 }
1572
1573 /*
1574  * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1575  * if necessary.
1576  *
1577  * Caller must hold RTNL and no other locks
1578  */
1579 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1580 {
1581         if (bond->slave_cnt > 1) {
1582                 alb_change_hw_addr_on_detach(bond, slave);
1583         }
1584
1585         tlb_clear_slave(bond, slave, 0);
1586
1587         if (bond->alb_info.rlb_enabled) {
1588                 bond->alb_info.next_rx_slave = NULL;
1589                 rlb_clear_slave(bond, slave);
1590         }
1591 }
1592
1593 /* Caller must hold bond lock for read */
1594 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1595 {
1596         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1597
1598         if (link == BOND_LINK_DOWN) {
1599                 tlb_clear_slave(bond, slave, 0);
1600                 if (bond->alb_info.rlb_enabled) {
1601                         rlb_clear_slave(bond, slave);
1602                 }
1603         } else if (link == BOND_LINK_UP) {
1604                 /* order a rebalance ASAP */
1605                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1606                 if (bond->alb_info.rlb_enabled) {
1607                         bond->alb_info.rlb_rebalance = 1;
1608                         /* If the updelay module parameter is smaller than the
1609                          * forwarding delay of the switch the rebalance will
1610                          * not work because the rebalance arp replies will
1611                          * not be forwarded to the clients..
1612                          */
1613                 }
1614         }
1615 }
1616
1617 /**
1618  * bond_alb_handle_active_change - assign new curr_active_slave
1619  * @bond: our bonding struct
1620  * @new_slave: new slave to assign
1621  *
1622  * Set the bond->curr_active_slave to @new_slave and handle
1623  * mac address swapping and promiscuity changes as needed.
1624  *
1625  * If new_slave is NULL, caller must hold curr_slave_lock or
1626  * bond->lock for write.
1627  *
1628  * If new_slave is not NULL, caller must hold RTNL, bond->lock for
1629  * read and curr_slave_lock for write.  Processing here may sleep, so
1630  * no other locks may be held.
1631  */
1632 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1633         __releases(&bond->curr_slave_lock)
1634         __releases(&bond->lock)
1635         __acquires(&bond->lock)
1636         __acquires(&bond->curr_slave_lock)
1637 {
1638         struct slave *swap_slave;
1639         int i;
1640
1641         if (bond->curr_active_slave == new_slave) {
1642                 return;
1643         }
1644
1645         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1646                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1647                 bond->alb_info.primary_is_promisc = 0;
1648                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1649         }
1650
1651         swap_slave = bond->curr_active_slave;
1652         bond->curr_active_slave = new_slave;
1653
1654         if (!new_slave || (bond->slave_cnt == 0)) {
1655                 return;
1656         }
1657
1658         /* set the new curr_active_slave to the bonds mac address
1659          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1660          */
1661         if (!swap_slave) {
1662                 struct slave *tmp_slave;
1663                 /* find slave that is holding the bond's mac address */
1664                 bond_for_each_slave(bond, tmp_slave, i) {
1665                         if (!compare_ether_addr_64bits(tmp_slave->dev->dev_addr,
1666                                                        bond->dev->dev_addr)) {
1667                                 swap_slave = tmp_slave;
1668                                 break;
1669                         }
1670                 }
1671         }
1672
1673         /*
1674          * Arrange for swap_slave and new_slave to temporarily be
1675          * ignored so we can mess with their MAC addresses without
1676          * fear of interference from transmit activity.
1677          */
1678         if (swap_slave) {
1679                 tlb_clear_slave(bond, swap_slave, 1);
1680         }
1681         tlb_clear_slave(bond, new_slave, 1);
1682
1683         write_unlock_bh(&bond->curr_slave_lock);
1684         read_unlock(&bond->lock);
1685
1686         ASSERT_RTNL();
1687
1688         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1689         if (swap_slave) {
1690                 /* swap mac address */
1691                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1692         } else {
1693                 /* set the new_slave to the bond mac address */
1694                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1695                                        bond->alb_info.rlb_enabled);
1696         }
1697
1698         if (swap_slave) {
1699                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1700                 read_lock(&bond->lock);
1701         } else {
1702                 read_lock(&bond->lock);
1703                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1704         }
1705
1706         write_lock_bh(&bond->curr_slave_lock);
1707 }
1708
1709 /*
1710  * Called with RTNL
1711  */
1712 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1713         __acquires(&bond->lock)
1714         __releases(&bond->lock)
1715 {
1716         struct bonding *bond = netdev_priv(bond_dev);
1717         struct sockaddr *sa = addr;
1718         struct slave *slave, *swap_slave;
1719         int res;
1720         int i;
1721
1722         if (!is_valid_ether_addr(sa->sa_data)) {
1723                 return -EADDRNOTAVAIL;
1724         }
1725
1726         res = alb_set_mac_address(bond, addr);
1727         if (res) {
1728                 return res;
1729         }
1730
1731         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1732
1733         /* If there is no curr_active_slave there is nothing else to do.
1734          * Otherwise we'll need to pass the new address to it and handle
1735          * duplications.
1736          */
1737         if (!bond->curr_active_slave) {
1738                 return 0;
1739         }
1740
1741         swap_slave = NULL;
1742
1743         bond_for_each_slave(bond, slave, i) {
1744                 if (!compare_ether_addr_64bits(slave->dev->dev_addr,
1745                                                bond_dev->dev_addr)) {
1746                         swap_slave = slave;
1747                         break;
1748                 }
1749         }
1750
1751         if (swap_slave) {
1752                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1753                 alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1754         } else {
1755                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1756                                        bond->alb_info.rlb_enabled);
1757
1758                 read_lock(&bond->lock);
1759                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1760                 if (bond->alb_info.rlb_enabled) {
1761                         /* inform clients mac address has changed */
1762                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1763                 }
1764                 read_unlock(&bond->lock);
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.current_alb_vlan &&
1773             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1774                 bond->alb_info.current_alb_vlan = NULL;
1775         }
1776
1777         if (bond->alb_info.rlb_enabled) {
1778                 rlb_clear_vlan(bond, vlan_id);
1779         }
1780 }
1781