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  * Changes:
  23  *
  24  * 2003/06/25 - Shmulik Hen <shmulik.hen at intel dot com>
  25  *      - Fixed signed/unsigned calculation errors that caused load sharing
  26  *        to collapse to one slave under very heavy UDP Tx stress.
  27  *
  28  * 2003/08/06 - Amir Noam <amir.noam at intel dot com>
  29  *      - Add support for setting bond's MAC address with special
  30  *        handling required for ALB/TLB.
  31  *
  32  * 2003/12/01 - Shmulik Hen <shmulik.hen at intel dot com>
  33  *      - Code cleanup and style changes
  34  *
  35  * 2003/12/30 - Amir Noam <amir.noam at intel dot com>
  36  *      - Fixed: Cannot remove and re-enslave the original active slave.
  37  *
  38  * 2004/01/14 - Shmulik Hen <shmulik.hen at intel dot com>
  39  *      - Add capability to tag self generated packets in ALB/TLB modes.
  40  */
  41
  42 //#define BONDING_DEBUG 1
  43
  44 #include <linux/skbuff.h>
  45 #include <linux/netdevice.h>
  46 #include <linux/etherdevice.h>
  47 #include <linux/pkt_sched.h>
  48 #include <linux/spinlock.h>
  49 #include <linux/slab.h>
  50 #include <linux/timer.h>
  51 #include <linux/ip.h>
  52 #include <linux/ipv6.h>
  53 #include <linux/if_arp.h>
  54 #include <linux/if_ether.h>
  55 #include <linux/if_bonding.h>
  56 #include <linux/if_vlan.h>
  57 #include <net/ipx.h>
  58 #include <net/arp.h>
  59 #include <asm/byteorder.h>
  60 #include "bonding.h"
  61 #include "bond_alb.h"
  62
  63
  64 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
  65 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
  66                                          * Used for division - never set
  67                                          * to zero !!!
  68                                          */
  69 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
  70                                          * learning packets to the switch
  71                                          */
  72
  73 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
  74                                   * ALB_TIMER_TICKS_PER_SEC)
  75
  76 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
  77                            * ALB_TIMER_TICKS_PER_SEC)
  78
  79 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
  80                                  * Note that this value MUST NOT be smaller
  81                                  * because the key hash table is BYTE wide !
  82                                  */
  83
  84
  85 #define TLB_NULL_INDEX          0xffffffff
  86 #define MAX_LP_BURST            3
  87
  88 /* rlb defs */
  89 #define RLB_HASH_TABLE_SIZE     256
  90 #define RLB_NULL_INDEX          0xffffffff
  91 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
  92 #define RLB_ARP_BURST_SIZE      2
  93 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
  94                                          * rebalance interval (5 min).
  95                                          */
  96 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
  97  * promiscuous after failover
  98  */
  99 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
 100
 101 static const u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
 102 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
 103
 104 #pragma pack(1)
 105 struct learning_pkt {
 106         u8 mac_dst[ETH_ALEN];
 107         u8 mac_src[ETH_ALEN];
 108         u16 type;
 109         u8 padding[ETH_ZLEN - ETH_HLEN];
 110 };
 111
 112 struct arp_pkt {
 113         u16     hw_addr_space;
 114         u16     prot_addr_space;
 115         u8      hw_addr_len;
 116         u8      prot_addr_len;
 117         u16     op_code;
 118         u8      mac_src[ETH_ALEN];      /* sender hardware address */
 119         u32     ip_src;                 /* sender IP address */
 120         u8      mac_dst[ETH_ALEN];      /* target hardware address */
 121         u32     ip_dst;                 /* target IP address */
 122 };
 123 #pragma pack()
 124
 125 /* Forward declaration */
 126 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
 127
 128 static inline u8 _simple_hash(u8 *hash_start, int hash_size)
 129 {
 130         int i;
 131         u8 hash = 0;
 132
 133         for (i = 0; i < hash_size; i++) {
 134                 hash ^= hash_start[i];
 135         }
 136
 137         return hash;
 138 }
 139
 140 /*********************** tlb specific functions ***************************/
 141
 142 static inline void _lock_tx_hashtbl(struct bonding *bond)
 143 {
 144         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 145 }
 146
 147 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 148 {
 149         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 150 }
 151
 152 /* Caller must hold tx_hashtbl lock */
 153 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 154 {
 155         if (save_load) {
 156                 entry->load_history = 1 + entry->tx_bytes /
 157                                       BOND_TLB_REBALANCE_INTERVAL;
 158                 entry->tx_bytes = 0;
 159         }
 160
 161         entry->tx_slave = NULL;
 162         entry->next = TLB_NULL_INDEX;
 163         entry->prev = TLB_NULL_INDEX;
 164 }
 165
 166 static inline void tlb_init_slave(struct slave *slave)
 167 {
 168         SLAVE_TLB_INFO(slave).load = 0;
 169         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 170 }
 171
 172 /* Caller must hold bond lock for read */
 173 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
 174 {
 175         struct tlb_client_info *tx_hash_table;
 176         u32 index;
 177
 178         _lock_tx_hashtbl(bond);
 179
 180         /* clear slave from tx_hashtbl */
 181         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 182
 183         index = SLAVE_TLB_INFO(slave).head;
 184         while (index != TLB_NULL_INDEX) {
 185                 u32 next_index = tx_hash_table[index].next;
 186                 tlb_init_table_entry(&tx_hash_table[index], save_load);
 187                 index = next_index;
 188         }
 189
 190         _unlock_tx_hashtbl(bond);
 191
 192         tlb_init_slave(slave);
 193 }
 194
 195 /* Must be called before starting the monitor timer */
 196 static int tlb_initialize(struct bonding *bond)
 197 {
 198         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 199         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 200         int i;
 201
 202         spin_lock_init(&(bond_info->tx_hashtbl_lock));
 203
 204         _lock_tx_hashtbl(bond);
 205
 206         bond_info->tx_hashtbl = kmalloc(size, GFP_KERNEL);
 207         if (!bond_info->tx_hashtbl) {
 208                 printk(KERN_ERR DRV_NAME
 209                        ": Error: %s: Failed to allocate TLB hash table\n",
 210                        bond->dev->name);
 211                 _unlock_tx_hashtbl(bond);
 212                 return -1;
 213         }
 214
 215         memset(bond_info->tx_hashtbl, 0, size);
 216
 217         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 218                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
 219         }
 220
 221         _unlock_tx_hashtbl(bond);
 222
 223         return 0;
 224 }
 225
 226 /* Must be called only after all slaves have been released */
 227 static void tlb_deinitialize(struct bonding *bond)
 228 {
 229         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 230
 231         _lock_tx_hashtbl(bond);
 232
 233         kfree(bond_info->tx_hashtbl);
 234         bond_info->tx_hashtbl = NULL;
 235
 236         _unlock_tx_hashtbl(bond);
 237 }
 238
 239 /* Caller must hold bond lock for read */
 240 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 241 {
 242         struct slave *slave, *least_loaded;
 243         s64 max_gap;
 244         int i, found = 0;
 245
 246         /* Find the first enabled slave */
 247         bond_for_each_slave(bond, slave, i) {
 248                 if (SLAVE_IS_OK(slave)) {
 249                         found = 1;
 250                         break;
 251                 }
 252         }
 253
 254         if (!found) {
 255                 return NULL;
 256         }
 257
 258         least_loaded = slave;
 259         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
 260                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 261
 262         /* Find the slave with the largest gap */
 263         bond_for_each_slave_from(bond, slave, i, least_loaded) {
 264                 if (SLAVE_IS_OK(slave)) {
 265                         s64 gap = (s64)(slave->speed << 20) -
 266                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
 267                         if (max_gap < gap) {
 268                                 least_loaded = slave;
 269                                 max_gap = gap;
 270                         }
 271                 }
 272         }
 273
 274         return least_loaded;
 275 }
 276
 277 /* Caller must hold bond lock for read */
 278 struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
 279 {
 280         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 281         struct tlb_client_info *hash_table;
 282         struct slave *assigned_slave;
 283
 284         _lock_tx_hashtbl(bond);
 285
 286         hash_table = bond_info->tx_hashtbl;
 287         assigned_slave = hash_table[hash_index].tx_slave;
 288         if (!assigned_slave) {
 289                 assigned_slave = tlb_get_least_loaded_slave(bond);
 290
 291                 if (assigned_slave) {
 292                         struct tlb_slave_info *slave_info =
 293                                 &(SLAVE_TLB_INFO(assigned_slave));
 294                         u32 next_index = slave_info->head;
 295
 296                         hash_table[hash_index].tx_slave = assigned_slave;
 297                         hash_table[hash_index].next = next_index;
 298                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 299
 300                         if (next_index != TLB_NULL_INDEX) {
 301                                 hash_table[next_index].prev = hash_index;
 302                         }
 303
 304                         slave_info->head = hash_index;
 305                         slave_info->load +=
 306                                 hash_table[hash_index].load_history;
 307                 }
 308         }
 309
 310         if (assigned_slave) {
 311                 hash_table[hash_index].tx_bytes += skb_len;
 312         }
 313
 314         _unlock_tx_hashtbl(bond);
 315
 316         return assigned_slave;
 317 }
 318
 319 /*********************** rlb specific functions ***************************/
 320 static inline void _lock_rx_hashtbl(struct bonding *bond)
 321 {
 322         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 323 }
 324
 325 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 326 {
 327         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 328 }
 329
 330 /* when an ARP REPLY is received from a client update its info
 331  * in the rx_hashtbl
 332  */
 333 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 334 {
 335         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 336         struct rlb_client_info *client_info;
 337         u32 hash_index;
 338
 339         _lock_rx_hashtbl(bond);
 340
 341         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 342         client_info = &(bond_info->rx_hashtbl[hash_index]);
 343
 344         if ((client_info->assigned) &&
 345             (client_info->ip_src == arp->ip_dst) &&
 346             (client_info->ip_dst == arp->ip_src)) {
 347                 /* update the clients MAC address */
 348                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 349                 client_info->ntt = 1;
 350                 bond_info->rx_ntt = 1;
 351         }
 352
 353         _unlock_rx_hashtbl(bond);
 354 }
 355
 356 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype)
 357 {
 358         struct bonding *bond = bond_dev->priv;
 359         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
 360         int res = NET_RX_DROP;
 361
 362         if (!(bond_dev->flags & IFF_MASTER)) {
 363                 goto out;
 364         }
 365
 366         if (!arp) {
 367                 dprintk("Packet has no ARP data\n");
 368                 goto out;
 369         }
 370
 371         if (skb->len < sizeof(struct arp_pkt)) {
 372                 dprintk("Packet is too small to be an ARP\n");
 373                 goto out;
 374         }
 375
 376         if (arp->op_code == htons(ARPOP_REPLY)) {
 377                 /* update rx hash table for this ARP */
 378                 rlb_update_entry_from_arp(bond, arp);
 379                 dprintk("Server received an ARP Reply from client\n");
 380         }
 381
 382         res = NET_RX_SUCCESS;
 383
 384 out:
 385         dev_kfree_skb(skb);
 386
 387         return res;
 388 }
 389
 390 /* Caller must hold bond lock for read */
 391 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 392 {
 393         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 394         struct slave *rx_slave, *slave, *start_at;
 395         int i = 0;
 396
 397         if (bond_info->next_rx_slave) {
 398                 start_at = bond_info->next_rx_slave;
 399         } else {
 400                 start_at = bond->first_slave;
 401         }
 402
 403         rx_slave = NULL;
 404
 405         bond_for_each_slave_from(bond, slave, i, start_at) {
 406                 if (SLAVE_IS_OK(slave)) {
 407                         if (!rx_slave) {
 408                                 rx_slave = slave;
 409                         } else if (slave->speed > rx_slave->speed) {
 410                                 rx_slave = slave;
 411                         }
 412                 }
 413         }
 414
 415         if (rx_slave) {
 416                 bond_info->next_rx_slave = rx_slave->next;
 417         }
 418
 419         return rx_slave;
 420 }
 421
 422 /* teach the switch the mac of a disabled slave
 423  * on the primary for fault tolerance
 424  *
 425  * Caller must hold bond->curr_slave_lock for write or bond lock for write
 426  */
 427 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 428 {
 429         if (!bond->curr_active_slave) {
 430                 return;
 431         }
 432
 433         if (!bond->alb_info.primary_is_promisc) {
 434                 bond->alb_info.primary_is_promisc = 1;
 435                 dev_set_promiscuity(bond->curr_active_slave->dev, 1);
 436         }
 437
 438         bond->alb_info.rlb_promisc_timeout_counter = 0;
 439
 440         alb_send_learning_packets(bond->curr_active_slave, addr);
 441 }
 442
 443 /* slave being removed should not be active at this point
 444  *
 445  * Caller must hold bond lock for read
 446  */
 447 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 448 {
 449         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 450         struct rlb_client_info *rx_hash_table;
 451         u32 index, next_index;
 452
 453         /* clear slave from rx_hashtbl */
 454         _lock_rx_hashtbl(bond);
 455
 456         rx_hash_table = bond_info->rx_hashtbl;
 457         index = bond_info->rx_hashtbl_head;
 458         for (; index != RLB_NULL_INDEX; index = next_index) {
 459                 next_index = rx_hash_table[index].next;
 460                 if (rx_hash_table[index].slave == slave) {
 461                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 462
 463                         if (assigned_slave) {
 464                                 rx_hash_table[index].slave = assigned_slave;
 465                                 if (memcmp(rx_hash_table[index].mac_dst,
 466                                            mac_bcast, ETH_ALEN)) {
 467                                         bond_info->rx_hashtbl[index].ntt = 1;
 468                                         bond_info->rx_ntt = 1;
 469                                         /* A slave has been removed from the
 470                                          * table because it is either disabled
 471                                          * or being released. We must retry the
 472                                          * update to avoid clients from not
 473                                          * being updated & disconnecting when
 474                                          * there is stress
 475                                          */
 476                                         bond_info->rlb_update_retry_counter =
 477                                                 RLB_UPDATE_RETRY;
 478                                 }
 479                         } else {  /* there is no active slave */
 480                                 rx_hash_table[index].slave = NULL;
 481                         }
 482                 }
 483         }
 484
 485         _unlock_rx_hashtbl(bond);
 486
 487         write_lock(&bond->curr_slave_lock);
 488
 489         if (slave != bond->curr_active_slave) {
 490                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 491         }
 492
 493         write_unlock(&bond->curr_slave_lock);
 494 }
 495
 496 static void rlb_update_client(struct rlb_client_info *client_info)
 497 {
 498         int i;
 499
 500         if (!client_info->slave) {
 501                 return;
 502         }
 503
 504         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 505                 struct sk_buff *skb;
 506
 507                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 508                                  client_info->ip_dst,
 509                                  client_info->slave->dev,
 510                                  client_info->ip_src,
 511                                  client_info->mac_dst,
 512                                  client_info->slave->dev->dev_addr,
 513                                  client_info->mac_dst);
 514                 if (!skb) {
 515                         printk(KERN_ERR DRV_NAME
 516                                ": Error: failed to create an ARP packet\n");
 517                         continue;
 518                 }
 519
 520                 skb->dev = client_info->slave->dev;
 521
 522                 if (client_info->tag) {
 523                         skb = vlan_put_tag(skb, client_info->vlan_id);
 524                         if (!skb) {
 525                                 printk(KERN_ERR DRV_NAME
 526                                        ": Error: failed to insert VLAN tag\n");
 527                                 continue;
 528                         }
 529                 }
 530
 531                 arp_xmit(skb);
 532         }
 533 }
 534
 535 /* sends ARP REPLIES that update the clients that need updating */
 536 static void rlb_update_rx_clients(struct bonding *bond)
 537 {
 538         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 539         struct rlb_client_info *client_info;
 540         u32 hash_index;
 541
 542         _lock_rx_hashtbl(bond);
 543
 544         hash_index = bond_info->rx_hashtbl_head;
 545         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 546                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 547                 if (client_info->ntt) {
 548                         rlb_update_client(client_info);
 549                         if (bond_info->rlb_update_retry_counter == 0) {
 550                                 client_info->ntt = 0;
 551                         }
 552                 }
 553         }
 554
 555         /* do not update the entries again untill this counter is zero so that
 556          * not to confuse the clients.
 557          */
 558         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 559
 560         _unlock_rx_hashtbl(bond);
 561 }
 562
 563 /* The slave was assigned a new mac address - update the clients */
 564 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 565 {
 566         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 567         struct rlb_client_info *client_info;
 568         int ntt = 0;
 569         u32 hash_index;
 570
 571         _lock_rx_hashtbl(bond);
 572
 573         hash_index = bond_info->rx_hashtbl_head;
 574         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 575                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 576
 577                 if ((client_info->slave == slave) &&
 578                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 579                         client_info->ntt = 1;
 580                         ntt = 1;
 581                 }
 582         }
 583
 584         // update the team's flag only after the whole iteration
 585         if (ntt) {
 586                 bond_info->rx_ntt = 1;
 587                 //fasten the change
 588                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 589         }
 590
 591         _unlock_rx_hashtbl(bond);
 592 }
 593
 594 /* mark all clients using src_ip to be updated */
 595 static void rlb_req_update_subnet_clients(struct bonding *bond, u32 src_ip)
 596 {
 597         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 598         struct rlb_client_info *client_info;
 599         u32 hash_index;
 600
 601         _lock_rx_hashtbl(bond);
 602
 603         hash_index = bond_info->rx_hashtbl_head;
 604         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 605                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 606
 607                 if (!client_info->slave) {
 608                         printk(KERN_ERR DRV_NAME
 609                                ": Error: found a client with no channel in "
 610                                "the client's hash table\n");
 611                         continue;
 612                 }
 613                 /*update all clients using this src_ip, that are not assigned
 614                  * to the team's address (curr_active_slave) and have a known
 615                  * unicast mac address.
 616                  */
 617                 if ((client_info->ip_src == src_ip) &&
 618                     memcmp(client_info->slave->dev->dev_addr,
 619                            bond->dev->dev_addr, ETH_ALEN) &&
 620                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 621                         client_info->ntt = 1;
 622                         bond_info->rx_ntt = 1;
 623                 }
 624         }
 625
 626         _unlock_rx_hashtbl(bond);
 627 }
 628
 629 /* Caller must hold both bond and ptr locks for read */
 630 struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 631 {
 632         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 633         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
 634         struct slave *assigned_slave;
 635         struct rlb_client_info *client_info;
 636         u32 hash_index = 0;
 637
 638         _lock_rx_hashtbl(bond);
 639
 640         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_src));
 641         client_info = &(bond_info->rx_hashtbl[hash_index]);
 642
 643         if (client_info->assigned) {
 644                 if ((client_info->ip_src == arp->ip_src) &&
 645                     (client_info->ip_dst == arp->ip_dst)) {
 646                         /* the entry is already assigned to this client */
 647                         if (memcmp(arp->mac_dst, mac_bcast, ETH_ALEN)) {
 648                                 /* update mac address from arp */
 649                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 650                         }
 651
 652                         assigned_slave = client_info->slave;
 653                         if (assigned_slave) {
 654                                 _unlock_rx_hashtbl(bond);
 655                                 return assigned_slave;
 656                         }
 657                 } else {
 658                         /* the entry is already assigned to some other client,
 659                          * move the old client to primary (curr_active_slave) so
 660                          * that the new client can be assigned to this entry.
 661                          */
 662                         if (bond->curr_active_slave &&
 663                             client_info->slave != bond->curr_active_slave) {
 664                                 client_info->slave = bond->curr_active_slave;
 665                                 rlb_update_client(client_info);
 666                         }
 667                 }
 668         }
 669         /* assign a new slave */
 670         assigned_slave = rlb_next_rx_slave(bond);
 671
 672         if (assigned_slave) {
 673                 client_info->ip_src = arp->ip_src;
 674                 client_info->ip_dst = arp->ip_dst;
 675                 /* arp->mac_dst is broadcast for arp reqeusts.
 676                  * will be updated with clients actual unicast mac address
 677                  * upon receiving an arp reply.
 678                  */
 679                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 680                 client_info->slave = assigned_slave;
 681
 682                 if (memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 683                         client_info->ntt = 1;
 684                         bond->alb_info.rx_ntt = 1;
 685                 } else {
 686                         client_info->ntt = 0;
 687                 }
 688
 689                 if (!list_empty(&bond->vlan_list)) {
 690                         unsigned short vlan_id;
 691                         int res = vlan_get_tag(skb, &vlan_id);
 692                         if (!res) {
 693                                 client_info->tag = 1;
 694                                 client_info->vlan_id = vlan_id;
 695                         }
 696                 }
 697
 698                 if (!client_info->assigned) {
 699                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
 700                         bond_info->rx_hashtbl_head = hash_index;
 701                         client_info->next = prev_tbl_head;
 702                         if (prev_tbl_head != RLB_NULL_INDEX) {
 703                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
 704                                         hash_index;
 705                         }
 706                         client_info->assigned = 1;
 707                 }
 708         }
 709
 710         _unlock_rx_hashtbl(bond);
 711
 712         return assigned_slave;
 713 }
 714
 715 /* chooses (and returns) transmit channel for arp reply
 716  * does not choose channel for other arp types since they are
 717  * sent on the curr_active_slave
 718  */
 719 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 720 {
 721         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
 722         struct slave *tx_slave = NULL;
 723
 724         if (arp->op_code == __constant_htons(ARPOP_REPLY)) {
 725                 /* the arp must be sent on the selected
 726                 * rx channel
 727                 */
 728                 tx_slave = rlb_choose_channel(skb, bond);
 729                 if (tx_slave) {
 730                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
 731                 }
 732                 dprintk("Server sent ARP Reply packet\n");
 733         } else if (arp->op_code == __constant_htons(ARPOP_REQUEST)) {
 734                 /* Create an entry in the rx_hashtbl for this client as a
 735                  * place holder.
 736                  * When the arp reply is received the entry will be updated
 737                  * with the correct unicast address of the client.
 738                  */
 739                 rlb_choose_channel(skb, bond);
 740
 741                 /* The ARP relpy packets must be delayed so that
 742                  * they can cancel out the influence of the ARP request.
 743                  */
 744                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 745
 746                 /* arp requests are broadcast and are sent on the primary
 747                  * the arp request will collapse all clients on the subnet to
 748                  * the primary slave. We must register these clients to be
 749                  * updated with their assigned mac.
 750                  */
 751                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 752                 dprintk("Server sent ARP Request packet\n");
 753         }
 754
 755         return tx_slave;
 756 }
 757
 758 /* Caller must hold bond lock for read */
 759 static void rlb_rebalance(struct bonding *bond)
 760 {
 761         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 762         struct slave *assigned_slave;
 763         struct rlb_client_info *client_info;
 764         int ntt;
 765         u32 hash_index;
 766
 767         _lock_rx_hashtbl(bond);
 768
 769         ntt = 0;
 770         hash_index = bond_info->rx_hashtbl_head;
 771         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 772                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 773                 assigned_slave = rlb_next_rx_slave(bond);
 774                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 775                         client_info->slave = assigned_slave;
 776                         client_info->ntt = 1;
 777                         ntt = 1;
 778                 }
 779         }
 780
 781         /* update the team's flag only after the whole iteration */
 782         if (ntt) {
 783                 bond_info->rx_ntt = 1;
 784         }
 785         _unlock_rx_hashtbl(bond);
 786 }
 787
 788 /* Caller must hold rx_hashtbl lock */
 789 static void rlb_init_table_entry(struct rlb_client_info *entry)
 790 {
 791         memset(entry, 0, sizeof(struct rlb_client_info));
 792         entry->next = RLB_NULL_INDEX;
 793         entry->prev = RLB_NULL_INDEX;
 794 }
 795
 796 static int rlb_initialize(struct bonding *bond)
 797 {
 798         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 799         struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
 800         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 801         int i;
 802
 803         spin_lock_init(&(bond_info->rx_hashtbl_lock));
 804
 805         _lock_rx_hashtbl(bond);
 806
 807         bond_info->rx_hashtbl = kmalloc(size, GFP_KERNEL);
 808         if (!bond_info->rx_hashtbl) {
 809                 printk(KERN_ERR DRV_NAME
 810                        ": Error: %s: Failed to allocate RLB hash table\n",
 811                        bond->dev->name);
 812                 _unlock_rx_hashtbl(bond);
 813                 return -1;
 814         }
 815
 816         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 817
 818         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
 819                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 820         }
 821
 822         _unlock_rx_hashtbl(bond);
 823
 824         /*initialize packet type*/
 825         pk_type->type = __constant_htons(ETH_P_ARP);
 826         pk_type->dev = bond->dev;
 827         pk_type->func = rlb_arp_recv;
 828
 829         /* register to receive ARPs */
 830         dev_add_pack(pk_type);
 831
 832         return 0;
 833 }
 834
 835 static void rlb_deinitialize(struct bonding *bond)
 836 {
 837         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 838
 839         dev_remove_pack(&(bond_info->rlb_pkt_type));
 840
 841         _lock_rx_hashtbl(bond);
 842
 843         kfree(bond_info->rx_hashtbl);
 844         bond_info->rx_hashtbl = NULL;
 845         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 846
 847         _unlock_rx_hashtbl(bond);
 848 }
 849
 850 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 851 {
 852         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 853         u32 curr_index;
 854
 855         _lock_rx_hashtbl(bond);
 856
 857         curr_index = bond_info->rx_hashtbl_head;
 858         while (curr_index != RLB_NULL_INDEX) {
 859                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 860                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
 861                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
 862
 863                 if (curr->tag && (curr->vlan_id == vlan_id)) {
 864                         if (curr_index == bond_info->rx_hashtbl_head) {
 865                                 bond_info->rx_hashtbl_head = next_index;
 866                         }
 867                         if (prev_index != RLB_NULL_INDEX) {
 868                                 bond_info->rx_hashtbl[prev_index].next = next_index;
 869                         }
 870                         if (next_index != RLB_NULL_INDEX) {
 871                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
 872                         }
 873
 874                         rlb_init_table_entry(curr);
 875                 }
 876
 877                 curr_index = next_index;
 878         }
 879
 880         _unlock_rx_hashtbl(bond);
 881 }
 882
 883 /*********************** tlb/rlb shared functions *********************/
 884
 885 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
 886 {
 887         struct bonding *bond = bond_get_bond_by_slave(slave);
 888         struct learning_pkt pkt;
 889         int size = sizeof(struct learning_pkt);
 890         int i;
 891
 892         memset(&pkt, 0, size);
 893         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
 894         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
 895         pkt.type = __constant_htons(ETH_P_LOOP);
 896
 897         for (i = 0; i < MAX_LP_BURST; i++) {
 898                 struct sk_buff *skb;
 899                 char *data;
 900
 901                 skb = dev_alloc_skb(size);
 902                 if (!skb) {
 903                         return;
 904                 }
 905
 906                 data = skb_put(skb, size);
 907                 memcpy(data, &pkt, size);
 908
 909                 skb->mac.raw = data;
 910                 skb->nh.raw = data + ETH_HLEN;
 911                 skb->protocol = pkt.type;
 912                 skb->priority = TC_PRIO_CONTROL;
 913                 skb->dev = slave->dev;
 914
 915                 if (!list_empty(&bond->vlan_list)) {
 916                         struct vlan_entry *vlan;
 917
 918                         vlan = bond_next_vlan(bond,
 919                                               bond->alb_info.current_alb_vlan);
 920
 921                         bond->alb_info.current_alb_vlan = vlan;
 922                         if (!vlan) {
 923                                 kfree_skb(skb);
 924                                 continue;
 925                         }
 926
 927                         skb = vlan_put_tag(skb, vlan->vlan_id);
 928                         if (!skb) {
 929                                 printk(KERN_ERR DRV_NAME
 930                                        ": Error: failed to insert VLAN tag\n");
 931                                 continue;
 932                         }
 933                 }
 934
 935                 dev_queue_xmit(skb);
 936         }
 937 }
 938
 939 /* hw is a boolean parameter that determines whether we should try and
 940  * set the hw address of the device as well as the hw address of the
 941  * net_device
 942  */
 943 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
 944 {
 945         struct net_device *dev = slave->dev;
 946         struct sockaddr s_addr;
 947
 948         if (!hw) {
 949                 memcpy(dev->dev_addr, addr, dev->addr_len);
 950                 return 0;
 951         }
 952
 953         /* for rlb each slave must have a unique hw mac addresses so that */
 954         /* each slave will receive packets destined to a different mac */
 955         memcpy(s_addr.sa_data, addr, dev->addr_len);
 956         s_addr.sa_family = dev->type;
 957         if (dev->set_mac_address(dev, &s_addr)) {
 958                 printk(KERN_ERR DRV_NAME
 959                        ": Error: dev->set_mac_address of dev %s failed! ALB "
 960                        "mode requires that the base driver support setting "
 961                        "the hw address also when the network device's "
 962                        "interface is open\n",
 963                        dev->name);
 964                 return -EOPNOTSUPP;
 965         }
 966         return 0;
 967 }
 968
 969 /* Caller must hold bond lock for write or curr_slave_lock for write*/
 970 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
 971 {
 972         struct slave *disabled_slave = NULL;
 973         u8 tmp_mac_addr[ETH_ALEN];
 974         int slaves_state_differ;
 975
 976         slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
 977
 978         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
 979         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
 980         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
 981
 982         /* fasten the change in the switch */
 983         if (SLAVE_IS_OK(slave1)) {
 984                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
 985                 if (bond->alb_info.rlb_enabled) {
 986                         /* inform the clients that the mac address
 987                          * has changed
 988                          */
 989                         rlb_req_update_slave_clients(bond, slave1);
 990                 }
 991         } else {
 992                 disabled_slave = slave1;
 993         }
 994
 995         if (SLAVE_IS_OK(slave2)) {
 996                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
 997                 if (bond->alb_info.rlb_enabled) {
 998                         /* inform the clients that the mac address
 999                          * has changed
1000                          */
1001                         rlb_req_update_slave_clients(bond, slave2);
1002                 }
1003         } else {
1004                 disabled_slave = slave2;
1005         }
1006
1007         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1008                 /* A disabled slave was assigned an active mac addr */
1009                 rlb_teach_disabled_mac_on_primary(bond,
1010                                                   disabled_slave->dev->dev_addr);
1011         }
1012 }
1013
1014 /**
1015  * alb_change_hw_addr_on_detach
1016  * @bond: bonding we're working on
1017  * @slave: the slave that was just detached
1018  *
1019  * We assume that @slave was already detached from the slave list.
1020  *
1021  * If @slave's permanent hw address is different both from its current
1022  * address and from @bond's address, then somewhere in the bond there's
1023  * a slave that has @slave's permanet address as its current address.
1024  * We'll make sure that that slave no longer uses @slave's permanent address.
1025  *
1026  * Caller must hold bond lock
1027  */
1028 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1029 {
1030         int perm_curr_diff;
1031         int perm_bond_diff;
1032
1033         perm_curr_diff = memcmp(slave->perm_hwaddr,
1034                                 slave->dev->dev_addr,
1035                                 ETH_ALEN);
1036         perm_bond_diff = memcmp(slave->perm_hwaddr,
1037                                 bond->dev->dev_addr,
1038                                 ETH_ALEN);
1039
1040         if (perm_curr_diff && perm_bond_diff) {
1041                 struct slave *tmp_slave;
1042                 int i, found = 0;
1043
1044                 bond_for_each_slave(bond, tmp_slave, i) {
1045                         if (!memcmp(slave->perm_hwaddr,
1046                                     tmp_slave->dev->dev_addr,
1047                                     ETH_ALEN)) {
1048                                 found = 1;
1049                                 break;
1050                         }
1051                 }
1052
1053                 if (found) {
1054                         alb_swap_mac_addr(bond, slave, tmp_slave);
1055                 }
1056         }
1057 }
1058
1059 /**
1060  * alb_handle_addr_collision_on_attach
1061  * @bond: bonding we're working on
1062  * @slave: the slave that was just attached
1063  *
1064  * checks uniqueness of slave's mac address and handles the case the
1065  * new slave uses the bonds mac address.
1066  *
1067  * If the permanent hw address of @slave is @bond's hw address, we need to
1068  * find a different hw address to give @slave, that isn't in use by any other
1069  * slave in the bond. This address must be, of course, one of the premanent
1070  * addresses of the other slaves.
1071  *
1072  * We go over the slave list, and for each slave there we compare its
1073  * permanent hw address with the current address of all the other slaves.
1074  * If no match was found, then we've found a slave with a permanent address
1075  * that isn't used by any other slave in the bond, so we can assign it to
1076  * @slave.
1077  *
1078  * assumption: this function is called before @slave is attached to the
1079  *             bond slave list.
1080  *
1081  * caller must hold the bond lock for write since the mac addresses are compared
1082  * and may be swapped.
1083  */
1084 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1085 {
1086         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1087         struct slave *has_bond_addr = bond->curr_active_slave;
1088         int i, j, found = 0;
1089
1090         if (bond->slave_cnt == 0) {
1091                 /* this is the first slave */
1092                 return 0;
1093         }
1094
1095         /* if slave's mac address differs from bond's mac address
1096          * check uniqueness of slave's mac address against the other
1097          * slaves in the bond.
1098          */
1099         if (memcmp(slave->perm_hwaddr, bond->dev->dev_addr, ETH_ALEN)) {
1100                 bond_for_each_slave(bond, tmp_slave1, i) {
1101                         if (!memcmp(tmp_slave1->dev->dev_addr, slave->dev->dev_addr,
1102                                     ETH_ALEN)) {
1103                                 found = 1;
1104                                 break;
1105                         }
1106                 }
1107
1108                 if (found) {
1109                         /* a slave was found that is using the mac address
1110                          * of the new slave
1111                          */
1112                         printk(KERN_ERR DRV_NAME
1113                                ": Error: the hw address of slave %s is not "
1114                                "unique - cannot enslave it!",
1115                                slave->dev->name);
1116                         return -EINVAL;
1117                 }
1118
1119                 return 0;
1120         }
1121
1122         /* The slave's address is equal to the address of the bond.
1123          * Search for a spare address in the bond for this slave.
1124          */
1125         free_mac_slave = NULL;
1126
1127         bond_for_each_slave(bond, tmp_slave1, i) {
1128                 found = 0;
1129                 bond_for_each_slave(bond, tmp_slave2, j) {
1130                         if (!memcmp(tmp_slave1->perm_hwaddr,
1131                                     tmp_slave2->dev->dev_addr,
1132                                     ETH_ALEN)) {
1133                                 found = 1;
1134                                 break;
1135                         }
1136                 }
1137
1138                 if (!found) {
1139                         /* no slave has tmp_slave1's perm addr
1140                          * as its curr addr
1141                          */
1142                         free_mac_slave = tmp_slave1;
1143                         break;
1144                 }
1145
1146                 if (!has_bond_addr) {
1147                         if (!memcmp(tmp_slave1->dev->dev_addr,
1148                                     bond->dev->dev_addr,
1149                                     ETH_ALEN)) {
1150
1151                                 has_bond_addr = tmp_slave1;
1152                         }
1153                 }
1154         }
1155
1156         if (free_mac_slave) {
1157                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1158                                        bond->alb_info.rlb_enabled);
1159
1160                 printk(KERN_WARNING DRV_NAME
1161                        ": Warning: the hw address of slave %s is in use by "
1162                        "the bond; giving it the hw address of %s\n",
1163                        slave->dev->name, free_mac_slave->dev->name);
1164
1165         } else if (has_bond_addr) {
1166                 printk(KERN_ERR DRV_NAME
1167                        ": Error: the hw address of slave %s is in use by the "
1168                        "bond; couldn't find a slave with a free hw address to "
1169                        "give it (this should not have happened)\n",
1170                        slave->dev->name);
1171                 return -EFAULT;
1172         }
1173
1174         return 0;
1175 }
1176
1177 /**
1178  * alb_set_mac_address
1179  * @bond:
1180  * @addr:
1181  *
1182  * In TLB mode all slaves are configured to the bond's hw address, but set
1183  * their dev_addr field to different addresses (based on their permanent hw
1184  * addresses).
1185  *
1186  * For each slave, this function sets the interface to the new address and then
1187  * changes its dev_addr field to its previous value.
1188  *
1189  * Unwinding assumes bond's mac address has not yet changed.
1190  */
1191 static int alb_set_mac_address(struct bonding *bond, void *addr)
1192 {
1193         struct sockaddr sa;
1194         struct slave *slave, *stop_at;
1195         char tmp_addr[ETH_ALEN];
1196         int res;
1197         int i;
1198
1199         if (bond->alb_info.rlb_enabled) {
1200                 return 0;
1201         }
1202
1203         bond_for_each_slave(bond, slave, i) {
1204                 if (slave->dev->set_mac_address == NULL) {
1205                         res = -EOPNOTSUPP;
1206                         goto unwind;
1207                 }
1208
1209                 /* save net_device's current hw address */
1210                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1211
1212                 res = slave->dev->set_mac_address(slave->dev, addr);
1213
1214                 /* restore net_device's hw address */
1215                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1216
1217                 if (res) {
1218                         goto unwind;
1219                 }
1220         }
1221
1222         return 0;
1223
1224 unwind:
1225         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1226         sa.sa_family = bond->dev->type;
1227
1228         /* unwind from head to the slave that failed */
1229         stop_at = slave;
1230         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1231                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1232                 slave->dev->set_mac_address(slave->dev, &sa);
1233                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1234         }
1235
1236         return res;
1237 }
1238
1239 /************************ exported alb funcions ************************/
1240
1241 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1242 {
1243         int res;
1244
1245         res = tlb_initialize(bond);
1246         if (res) {
1247                 return res;
1248         }
1249
1250         if (rlb_enabled) {
1251                 bond->alb_info.rlb_enabled = 1;
1252                 /* initialize rlb */
1253                 res = rlb_initialize(bond);
1254                 if (res) {
1255                         tlb_deinitialize(bond);
1256                         return res;
1257                 }
1258         }
1259
1260         return 0;
1261 }
1262
1263 void bond_alb_deinitialize(struct bonding *bond)
1264 {
1265         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1266
1267         tlb_deinitialize(bond);
1268
1269         if (bond_info->rlb_enabled) {
1270                 rlb_deinitialize(bond);
1271         }
1272 }
1273
1274 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1275 {
1276         struct bonding *bond = bond_dev->priv;
1277         struct ethhdr *eth_data;
1278         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1279         struct slave *tx_slave = NULL;
1280         static u32 ip_bcast = 0xffffffff;
1281         int hash_size = 0;
1282         int do_tx_balance = 1;
1283         u32 hash_index = 0;
1284         u8 *hash_start = NULL;
1285         int res = 1;
1286
1287         skb->mac.raw = (unsigned char *)skb->data;
1288         eth_data = eth_hdr(skb);
1289
1290         /* make sure that the curr_active_slave and the slaves list do
1291          * not change during tx
1292          */
1293         read_lock(&bond->lock);
1294         read_lock(&bond->curr_slave_lock);
1295
1296         if (!BOND_IS_OK(bond)) {
1297                 goto out;
1298         }
1299
1300         switch (ntohs(skb->protocol)) {
1301         case ETH_P_IP:
1302                 if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
1303                     (skb->nh.iph->daddr == ip_bcast)) {
1304                         do_tx_balance = 0;
1305                         break;
1306                 }
1307                 hash_start = (char*)&(skb->nh.iph->daddr);
1308                 hash_size = sizeof(skb->nh.iph->daddr);
1309                 break;
1310         case ETH_P_IPV6:
1311                 if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
1312                         do_tx_balance = 0;
1313                         break;
1314                 }
1315
1316                 hash_start = (char*)&(skb->nh.ipv6h->daddr);
1317                 hash_size = sizeof(skb->nh.ipv6h->daddr);
1318                 break;
1319         case ETH_P_IPX:
1320                 if (ipx_hdr(skb)->ipx_checksum !=
1321                     __constant_htons(IPX_NO_CHECKSUM)) {
1322                         /* something is wrong with this packet */
1323                         do_tx_balance = 0;
1324                         break;
1325                 }
1326
1327                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1328                         /* The only protocol worth balancing in
1329                          * this family since it has an "ARP" like
1330                          * mechanism
1331                          */
1332                         do_tx_balance = 0;
1333                         break;
1334                 }
1335
1336                 hash_start = (char*)eth_data->h_dest;
1337                 hash_size = ETH_ALEN;
1338                 break;
1339         case ETH_P_ARP:
1340                 do_tx_balance = 0;
1341                 if (bond_info->rlb_enabled) {
1342                         tx_slave = rlb_arp_xmit(skb, bond);
1343                 }
1344                 break;
1345         default:
1346                 do_tx_balance = 0;
1347                 break;
1348         }
1349
1350         if (do_tx_balance) {
1351                 hash_index = _simple_hash(hash_start, hash_size);
1352                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1353         }
1354
1355         if (!tx_slave) {
1356                 /* unbalanced or unassigned, send through primary */
1357                 tx_slave = bond->curr_active_slave;
1358                 bond_info->unbalanced_load += skb->len;
1359         }
1360
1361         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1362                 if (tx_slave != bond->curr_active_slave) {
1363                         memcpy(eth_data->h_source,
1364                                tx_slave->dev->dev_addr,
1365                                ETH_ALEN);
1366                 }
1367
1368                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1369         } else {
1370                 if (tx_slave) {
1371                         tlb_clear_slave(bond, tx_slave, 0);
1372                 }
1373         }
1374
1375 out:
1376         if (res) {
1377                 /* no suitable interface, frame not sent */
1378                 dev_kfree_skb(skb);
1379         }
1380         read_unlock(&bond->curr_slave_lock);
1381         read_unlock(&bond->lock);
1382         return 0;
1383 }
1384
1385 void bond_alb_monitor(struct bonding *bond)
1386 {
1387         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1388         struct slave *slave;
1389         int i;
1390
1391         read_lock(&bond->lock);
1392
1393         if (bond->kill_timers) {
1394                 goto out;
1395         }
1396
1397         if (bond->slave_cnt == 0) {
1398                 bond_info->tx_rebalance_counter = 0;
1399                 bond_info->lp_counter = 0;
1400                 goto re_arm;
1401         }
1402
1403         bond_info->tx_rebalance_counter++;
1404         bond_info->lp_counter++;
1405
1406         /* send learning packets */
1407         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1408                 /* change of curr_active_slave involves swapping of mac addresses.
1409                  * in order to avoid this swapping from happening while
1410                  * sending the learning packets, the curr_slave_lock must be held for
1411                  * read.
1412                  */
1413                 read_lock(&bond->curr_slave_lock);
1414
1415                 bond_for_each_slave(bond, slave, i) {
1416                         alb_send_learning_packets(slave,slave->dev->dev_addr);
1417                 }
1418
1419                 read_unlock(&bond->curr_slave_lock);
1420
1421                 bond_info->lp_counter = 0;
1422         }
1423
1424         /* rebalance tx traffic */
1425         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1426
1427                 read_lock(&bond->curr_slave_lock);
1428
1429                 bond_for_each_slave(bond, slave, i) {
1430                         tlb_clear_slave(bond, slave, 1);
1431                         if (slave == bond->curr_active_slave) {
1432                                 SLAVE_TLB_INFO(slave).load =
1433                                         bond_info->unbalanced_load /
1434                                                 BOND_TLB_REBALANCE_INTERVAL;
1435                                 bond_info->unbalanced_load = 0;
1436                         }
1437                 }
1438
1439                 read_unlock(&bond->curr_slave_lock);
1440
1441                 bond_info->tx_rebalance_counter = 0;
1442         }
1443
1444         /* handle rlb stuff */
1445         if (bond_info->rlb_enabled) {
1446                 /* the following code changes the promiscuity of the
1447                  * the curr_active_slave. It needs to be locked with a
1448                  * write lock to protect from other code that also
1449                  * sets the promiscuity.
1450                  */
1451                 write_lock(&bond->curr_slave_lock);
1452
1453                 if (bond_info->primary_is_promisc &&
1454                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1455
1456                         bond_info->rlb_promisc_timeout_counter = 0;
1457
1458                         /* If the primary was set to promiscuous mode
1459                          * because a slave was disabled then
1460                          * it can now leave promiscuous mode.
1461                          */
1462                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1463                         bond_info->primary_is_promisc = 0;
1464                 }
1465
1466                 write_unlock(&bond->curr_slave_lock);
1467
1468                 if (bond_info->rlb_rebalance) {
1469                         bond_info->rlb_rebalance = 0;
1470                         rlb_rebalance(bond);
1471                 }
1472
1473                 /* check if clients need updating */
1474                 if (bond_info->rx_ntt) {
1475                         if (bond_info->rlb_update_delay_counter) {
1476                                 --bond_info->rlb_update_delay_counter;
1477                         } else {
1478                                 rlb_update_rx_clients(bond);
1479                                 if (bond_info->rlb_update_retry_counter) {
1480                                         --bond_info->rlb_update_retry_counter;
1481                                 } else {
1482                                         bond_info->rx_ntt = 0;
1483                                 }
1484                         }
1485                 }
1486         }
1487
1488 re_arm:
1489         mod_timer(&(bond_info->alb_timer), jiffies + alb_delta_in_ticks);
1490 out:
1491         read_unlock(&bond->lock);
1492 }
1493
1494 /* assumption: called before the slave is attached to the bond
1495  * and not locked by the bond lock
1496  */
1497 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1498 {
1499         int res;
1500
1501         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1502                                      bond->alb_info.rlb_enabled);
1503         if (res) {
1504                 return res;
1505         }
1506
1507         /* caller must hold the bond lock for write since the mac addresses
1508          * are compared and may be swapped.
1509          */
1510         write_lock_bh(&bond->lock);
1511
1512         res = alb_handle_addr_collision_on_attach(bond, slave);
1513
1514         write_unlock_bh(&bond->lock);
1515
1516         if (res) {
1517                 return res;
1518         }
1519
1520         tlb_init_slave(slave);
1521
1522         /* order a rebalance ASAP */
1523         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1524
1525         if (bond->alb_info.rlb_enabled) {
1526                 bond->alb_info.rlb_rebalance = 1;
1527         }
1528
1529         return 0;
1530 }
1531
1532 /* Caller must hold bond lock for write */
1533 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1534 {
1535         if (bond->slave_cnt > 1) {
1536                 alb_change_hw_addr_on_detach(bond, slave);
1537         }
1538
1539         tlb_clear_slave(bond, slave, 0);
1540
1541         if (bond->alb_info.rlb_enabled) {
1542                 bond->alb_info.next_rx_slave = NULL;
1543                 rlb_clear_slave(bond, slave);
1544         }
1545 }
1546
1547 /* Caller must hold bond lock for read */
1548 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1549 {
1550         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1551
1552         if (link == BOND_LINK_DOWN) {
1553                 tlb_clear_slave(bond, slave, 0);
1554                 if (bond->alb_info.rlb_enabled) {
1555                         rlb_clear_slave(bond, slave);
1556                 }
1557         } else if (link == BOND_LINK_UP) {
1558                 /* order a rebalance ASAP */
1559                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1560                 if (bond->alb_info.rlb_enabled) {
1561                         bond->alb_info.rlb_rebalance = 1;
1562                         /* If the updelay module parameter is smaller than the
1563                          * forwarding delay of the switch the rebalance will
1564                          * not work because the rebalance arp replies will
1565                          * not be forwarded to the clients..
1566                          */
1567                 }
1568         }
1569 }
1570
1571 /**
1572  * bond_alb_handle_active_change - assign new curr_active_slave
1573  * @bond: our bonding struct
1574  * @new_slave: new slave to assign
1575  *
1576  * Set the bond->curr_active_slave to @new_slave and handle
1577  * mac address swapping and promiscuity changes as needed.
1578  *
1579  * Caller must hold bond curr_slave_lock for write (or bond lock for write)
1580  */
1581 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1582 {
1583         struct slave *swap_slave;
1584         int i;
1585
1586         if (bond->curr_active_slave == new_slave) {
1587                 return;
1588         }
1589
1590         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1591                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1592                 bond->alb_info.primary_is_promisc = 0;
1593                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1594         }
1595
1596         swap_slave = bond->curr_active_slave;
1597         bond->curr_active_slave = new_slave;
1598
1599         if (!new_slave || (bond->slave_cnt == 0)) {
1600                 return;
1601         }
1602
1603         /* set the new curr_active_slave to the bonds mac address
1604          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1605          */
1606         if (!swap_slave) {
1607                 struct slave *tmp_slave;
1608                 /* find slave that is holding the bond's mac address */
1609                 bond_for_each_slave(bond, tmp_slave, i) {
1610                         if (!memcmp(tmp_slave->dev->dev_addr,
1611                                     bond->dev->dev_addr, ETH_ALEN)) {
1612                                 swap_slave = tmp_slave;
1613                                 break;
1614                         }
1615                 }
1616         }
1617
1618         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1619         if (swap_slave) {
1620                 /* swap mac address */
1621                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1622         } else {
1623                 /* set the new_slave to the bond mac address */
1624                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1625                                        bond->alb_info.rlb_enabled);
1626                 /* fasten bond mac on new current slave */
1627                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1628         }
1629 }
1630
1631 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1632 {
1633         struct bonding *bond = bond_dev->priv;
1634         struct sockaddr *sa = addr;
1635         struct slave *slave, *swap_slave;
1636         int res;
1637         int i;
1638
1639         if (!is_valid_ether_addr(sa->sa_data)) {
1640                 return -EADDRNOTAVAIL;
1641         }
1642
1643         res = alb_set_mac_address(bond, addr);
1644         if (res) {
1645                 return res;
1646         }
1647
1648         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1649
1650         /* If there is no curr_active_slave there is nothing else to do.
1651          * Otherwise we'll need to pass the new address to it and handle
1652          * duplications.
1653          */
1654         if (!bond->curr_active_slave) {
1655                 return 0;
1656         }
1657
1658         swap_slave = NULL;
1659
1660         bond_for_each_slave(bond, slave, i) {
1661                 if (!memcmp(slave->dev->dev_addr, bond_dev->dev_addr, ETH_ALEN)) {
1662                         swap_slave = slave;
1663                         break;
1664                 }
1665         }
1666
1667         if (swap_slave) {
1668                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1669         } else {
1670                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1671                                        bond->alb_info.rlb_enabled);
1672
1673                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1674                 if (bond->alb_info.rlb_enabled) {
1675                         /* inform clients mac address has changed */
1676                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1677                 }
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