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 <linux/in.h>
  58 #include <net/ipx.h>
  59 #include <net/arp.h>
  60 #include <asm/byteorder.h>
  61 #include "bonding.h"
  62 #include "bond_alb.h"
  63
  64
  65 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
  66 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
  67                                          * Used for division - never set
  68                                          * to zero !!!
  69                                          */
  70 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
  71                                          * learning packets to the switch
  72                                          */
  73
  74 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
  75                                   * ALB_TIMER_TICKS_PER_SEC)
  76
  77 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
  78                            * ALB_TIMER_TICKS_PER_SEC)
  79
  80 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
  81                                  * Note that this value MUST NOT be smaller
  82                                  * because the key hash table is BYTE wide !
  83                                  */
  84
  85
  86 #define TLB_NULL_INDEX          0xffffffff
  87 #define MAX_LP_BURST            3
  88
  89 /* rlb defs */
  90 #define RLB_HASH_TABLE_SIZE     256
  91 #define RLB_NULL_INDEX          0xffffffff
  92 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
  93 #define RLB_ARP_BURST_SIZE      2
  94 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
  95                                          * rebalance interval (5 min).
  96                                          */
  97 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
  98  * promiscuous after failover
  99  */
 100 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
 101
 102 static const u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
 103 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
 104
 105 #pragma pack(1)
 106 struct learning_pkt {
 107         u8 mac_dst[ETH_ALEN];
 108         u8 mac_src[ETH_ALEN];
 109         u16 type;
 110         u8 padding[ETH_ZLEN - ETH_HLEN];
 111 };
 112
 113 struct arp_pkt {
 114         u16     hw_addr_space;
 115         u16     prot_addr_space;
 116         u8      hw_addr_len;
 117         u8      prot_addr_len;
 118         u16     op_code;
 119         u8      mac_src[ETH_ALEN];      /* sender hardware address */
 120         u32     ip_src;                 /* sender IP address */
 121         u8      mac_dst[ETH_ALEN];      /* target hardware address */
 122         u32     ip_dst;                 /* target IP address */
 123 };
 124 #pragma pack()
 125
 126 /* Forward declaration */
 127 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
 128
 129 static inline u8 _simple_hash(u8 *hash_start, int hash_size)
 130 {
 131         int i;
 132         u8 hash = 0;
 133
 134         for (i = 0; i < hash_size; i++) {
 135                 hash ^= hash_start[i];
 136         }
 137
 138         return hash;
 139 }
 140
 141 /*********************** tlb specific functions ***************************/
 142
 143 static inline void _lock_tx_hashtbl(struct bonding *bond)
 144 {
 145         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 146 }
 147
 148 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 149 {
 150         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 151 }
 152
 153 /* Caller must hold tx_hashtbl lock */
 154 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 155 {
 156         if (save_load) {
 157                 entry->load_history = 1 + entry->tx_bytes /
 158                                       BOND_TLB_REBALANCE_INTERVAL;
 159                 entry->tx_bytes = 0;
 160         }
 161
 162         entry->tx_slave = NULL;
 163         entry->next = TLB_NULL_INDEX;
 164         entry->prev = TLB_NULL_INDEX;
 165 }
 166
 167 static inline void tlb_init_slave(struct slave *slave)
 168 {
 169         SLAVE_TLB_INFO(slave).load = 0;
 170         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 171 }
 172
 173 /* Caller must hold bond lock for read */
 174 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
 175 {
 176         struct tlb_client_info *tx_hash_table;
 177         u32 index;
 178
 179         _lock_tx_hashtbl(bond);
 180
 181         /* clear slave from tx_hashtbl */
 182         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 183
 184         index = SLAVE_TLB_INFO(slave).head;
 185         while (index != TLB_NULL_INDEX) {
 186                 u32 next_index = tx_hash_table[index].next;
 187                 tlb_init_table_entry(&tx_hash_table[index], save_load);
 188                 index = next_index;
 189         }
 190
 191         _unlock_tx_hashtbl(bond);
 192
 193         tlb_init_slave(slave);
 194 }
 195
 196 /* Must be called before starting the monitor timer */
 197 static int tlb_initialize(struct bonding *bond)
 198 {
 199         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 200         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 201         int i;
 202
 203         spin_lock_init(&(bond_info->tx_hashtbl_lock));
 204
 205         _lock_tx_hashtbl(bond);
 206
 207         bond_info->tx_hashtbl = kmalloc(size, GFP_KERNEL);
 208         if (!bond_info->tx_hashtbl) {
 209                 printk(KERN_ERR DRV_NAME
 210                        ": Error: %s: Failed to allocate TLB hash table\n",
 211                        bond->dev->name);
 212                 _unlock_tx_hashtbl(bond);
 213                 return -1;
 214         }
 215
 216         memset(bond_info->tx_hashtbl, 0, size);
 217
 218         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 219                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
 220         }
 221
 222         _unlock_tx_hashtbl(bond);
 223
 224         return 0;
 225 }
 226
 227 /* Must be called only after all slaves have been released */
 228 static void tlb_deinitialize(struct bonding *bond)
 229 {
 230         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 231
 232         _lock_tx_hashtbl(bond);
 233
 234         kfree(bond_info->tx_hashtbl);
 235         bond_info->tx_hashtbl = NULL;
 236
 237         _unlock_tx_hashtbl(bond);
 238 }
 239
 240 /* Caller must hold bond lock for read */
 241 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 242 {
 243         struct slave *slave, *least_loaded;
 244         s64 max_gap;
 245         int i, found = 0;
 246
 247         /* Find the first enabled slave */
 248         bond_for_each_slave(bond, slave, i) {
 249                 if (SLAVE_IS_OK(slave)) {
 250                         found = 1;
 251                         break;
 252                 }
 253         }
 254
 255         if (!found) {
 256                 return NULL;
 257         }
 258
 259         least_loaded = slave;
 260         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
 261                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 262
 263         /* Find the slave with the largest gap */
 264         bond_for_each_slave_from(bond, slave, i, least_loaded) {
 265                 if (SLAVE_IS_OK(slave)) {
 266                         s64 gap = (s64)(slave->speed << 20) -
 267                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
 268                         if (max_gap < gap) {
 269                                 least_loaded = slave;
 270                                 max_gap = gap;
 271                         }
 272                 }
 273         }
 274
 275         return least_loaded;
 276 }
 277
 278 /* Caller must hold bond lock for read */
 279 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
 280 {
 281         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 282         struct tlb_client_info *hash_table;
 283         struct slave *assigned_slave;
 284
 285         _lock_tx_hashtbl(bond);
 286
 287         hash_table = bond_info->tx_hashtbl;
 288         assigned_slave = hash_table[hash_index].tx_slave;
 289         if (!assigned_slave) {
 290                 assigned_slave = tlb_get_least_loaded_slave(bond);
 291
 292                 if (assigned_slave) {
 293                         struct tlb_slave_info *slave_info =
 294                                 &(SLAVE_TLB_INFO(assigned_slave));
 295                         u32 next_index = slave_info->head;
 296
 297                         hash_table[hash_index].tx_slave = assigned_slave;
 298                         hash_table[hash_index].next = next_index;
 299                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 300
 301                         if (next_index != TLB_NULL_INDEX) {
 302                                 hash_table[next_index].prev = hash_index;
 303                         }
 304
 305                         slave_info->head = hash_index;
 306                         slave_info->load +=
 307                                 hash_table[hash_index].load_history;
 308                 }
 309         }
 310
 311         if (assigned_slave) {
 312                 hash_table[hash_index].tx_bytes += skb_len;
 313         }
 314
 315         _unlock_tx_hashtbl(bond);
 316
 317         return assigned_slave;
 318 }
 319
 320 /*********************** rlb specific functions ***************************/
 321 static inline void _lock_rx_hashtbl(struct bonding *bond)
 322 {
 323         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 324 }
 325
 326 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 327 {
 328         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 329 }
 330
 331 /* when an ARP REPLY is received from a client update its info
 332  * in the rx_hashtbl
 333  */
 334 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 335 {
 336         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 337         struct rlb_client_info *client_info;
 338         u32 hash_index;
 339
 340         _lock_rx_hashtbl(bond);
 341
 342         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 343         client_info = &(bond_info->rx_hashtbl[hash_index]);
 344
 345         if ((client_info->assigned) &&
 346             (client_info->ip_src == arp->ip_dst) &&
 347             (client_info->ip_dst == arp->ip_src)) {
 348                 /* update the clients MAC address */
 349                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 350                 client_info->ntt = 1;
 351                 bond_info->rx_ntt = 1;
 352         }
 353
 354         _unlock_rx_hashtbl(bond);
 355 }
 356
 357 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype, struct net_device *orig_dev)
 358 {
 359         struct bonding *bond = bond_dev->priv;
 360         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
 361         int res = NET_RX_DROP;
 362
 363         if (!(bond_dev->flags & IFF_MASTER))
 364                 goto out;
 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 static 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                         return 0;
1110
1111                 /* Try setting slave mac to bond address and fall-through
1112                    to code handling that situation below... */
1113                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1114                                        bond->alb_info.rlb_enabled);
1115         }
1116
1117         /* The slave's address is equal to the address of the bond.
1118          * Search for a spare address in the bond for this slave.
1119          */
1120         free_mac_slave = NULL;
1121
1122         bond_for_each_slave(bond, tmp_slave1, i) {
1123                 found = 0;
1124                 bond_for_each_slave(bond, tmp_slave2, j) {
1125                         if (!memcmp(tmp_slave1->perm_hwaddr,
1126                                     tmp_slave2->dev->dev_addr,
1127                                     ETH_ALEN)) {
1128                                 found = 1;
1129                                 break;
1130                         }
1131                 }
1132
1133                 if (!found) {
1134                         /* no slave has tmp_slave1's perm addr
1135                          * as its curr addr
1136                          */
1137                         free_mac_slave = tmp_slave1;
1138                         break;
1139                 }
1140
1141                 if (!has_bond_addr) {
1142                         if (!memcmp(tmp_slave1->dev->dev_addr,
1143                                     bond->dev->dev_addr,
1144                                     ETH_ALEN)) {
1145
1146                                 has_bond_addr = tmp_slave1;
1147                         }
1148                 }
1149         }
1150
1151         if (free_mac_slave) {
1152                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1153                                        bond->alb_info.rlb_enabled);
1154
1155                 printk(KERN_WARNING DRV_NAME
1156                        ": Warning: the hw address of slave %s is in use by "
1157                        "the bond; giving it the hw address of %s\n",
1158                        slave->dev->name, free_mac_slave->dev->name);
1159
1160         } else if (has_bond_addr) {
1161                 printk(KERN_ERR DRV_NAME
1162                        ": Error: the hw address of slave %s is in use by the "
1163                        "bond; couldn't find a slave with a free hw address to "
1164                        "give it (this should not have happened)\n",
1165                        slave->dev->name);
1166                 return -EFAULT;
1167         }
1168
1169         return 0;
1170 }
1171
1172 /**
1173  * alb_set_mac_address
1174  * @bond:
1175  * @addr:
1176  *
1177  * In TLB mode all slaves are configured to the bond's hw address, but set
1178  * their dev_addr field to different addresses (based on their permanent hw
1179  * addresses).
1180  *
1181  * For each slave, this function sets the interface to the new address and then
1182  * changes its dev_addr field to its previous value.
1183  *
1184  * Unwinding assumes bond's mac address has not yet changed.
1185  */
1186 static int alb_set_mac_address(struct bonding *bond, void *addr)
1187 {
1188         struct sockaddr sa;
1189         struct slave *slave, *stop_at;
1190         char tmp_addr[ETH_ALEN];
1191         int res;
1192         int i;
1193
1194         if (bond->alb_info.rlb_enabled) {
1195                 return 0;
1196         }
1197
1198         bond_for_each_slave(bond, slave, i) {
1199                 if (slave->dev->set_mac_address == NULL) {
1200                         res = -EOPNOTSUPP;
1201                         goto unwind;
1202                 }
1203
1204                 /* save net_device's current hw address */
1205                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1206
1207                 res = dev_set_mac_address(slave->dev, addr);
1208
1209                 /* restore net_device's hw address */
1210                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1211
1212                 if (res) {
1213                         goto unwind;
1214                 }
1215         }
1216
1217         return 0;
1218
1219 unwind:
1220         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1221         sa.sa_family = bond->dev->type;
1222
1223         /* unwind from head to the slave that failed */
1224         stop_at = slave;
1225         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1226                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1227                 dev_set_mac_address(slave->dev, &sa);
1228                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1229         }
1230
1231         return res;
1232 }
1233
1234 /************************ exported alb funcions ************************/
1235
1236 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1237 {
1238         int res;
1239
1240         res = tlb_initialize(bond);
1241         if (res) {
1242                 return res;
1243         }
1244
1245         if (rlb_enabled) {
1246                 bond->alb_info.rlb_enabled = 1;
1247                 /* initialize rlb */
1248                 res = rlb_initialize(bond);
1249                 if (res) {
1250                         tlb_deinitialize(bond);
1251                         return res;
1252                 }
1253         }
1254
1255         return 0;
1256 }
1257
1258 void bond_alb_deinitialize(struct bonding *bond)
1259 {
1260         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1261
1262         tlb_deinitialize(bond);
1263
1264         if (bond_info->rlb_enabled) {
1265                 rlb_deinitialize(bond);
1266         }
1267 }
1268
1269 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1270 {
1271         struct bonding *bond = bond_dev->priv;
1272         struct ethhdr *eth_data;
1273         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1274         struct slave *tx_slave = NULL;
1275         static u32 ip_bcast = 0xffffffff;
1276         int hash_size = 0;
1277         int do_tx_balance = 1;
1278         u32 hash_index = 0;
1279         u8 *hash_start = NULL;
1280         int res = 1;
1281
1282         skb->mac.raw = (unsigned char *)skb->data;
1283         eth_data = eth_hdr(skb);
1284
1285         /* make sure that the curr_active_slave and the slaves list do
1286          * not change during tx
1287          */
1288         read_lock(&bond->lock);
1289         read_lock(&bond->curr_slave_lock);
1290
1291         if (!BOND_IS_OK(bond)) {
1292                 goto out;
1293         }
1294
1295         switch (ntohs(skb->protocol)) {
1296         case ETH_P_IP:
1297                 if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
1298                     (skb->nh.iph->daddr == ip_bcast) ||
1299                     (skb->nh.iph->protocol == IPPROTO_IGMP)) {
1300                         do_tx_balance = 0;
1301                         break;
1302                 }
1303                 hash_start = (char*)&(skb->nh.iph->daddr);
1304                 hash_size = sizeof(skb->nh.iph->daddr);
1305                 break;
1306         case ETH_P_IPV6:
1307                 if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
1308                         do_tx_balance = 0;
1309                         break;
1310                 }
1311
1312                 hash_start = (char*)&(skb->nh.ipv6h->daddr);
1313                 hash_size = sizeof(skb->nh.ipv6h->daddr);
1314                 break;
1315         case ETH_P_IPX:
1316                 if (ipx_hdr(skb)->ipx_checksum !=
1317                     __constant_htons(IPX_NO_CHECKSUM)) {
1318                         /* something is wrong with this packet */
1319                         do_tx_balance = 0;
1320                         break;
1321                 }
1322
1323                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1324                         /* The only protocol worth balancing in
1325                          * this family since it has an "ARP" like
1326                          * mechanism
1327                          */
1328                         do_tx_balance = 0;
1329                         break;
1330                 }
1331
1332                 hash_start = (char*)eth_data->h_dest;
1333                 hash_size = ETH_ALEN;
1334                 break;
1335         case ETH_P_ARP:
1336                 do_tx_balance = 0;
1337                 if (bond_info->rlb_enabled) {
1338                         tx_slave = rlb_arp_xmit(skb, bond);
1339                 }
1340                 break;
1341         default:
1342                 do_tx_balance = 0;
1343                 break;
1344         }
1345
1346         if (do_tx_balance) {
1347                 hash_index = _simple_hash(hash_start, hash_size);
1348                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1349         }
1350
1351         if (!tx_slave) {
1352                 /* unbalanced or unassigned, send through primary */
1353                 tx_slave = bond->curr_active_slave;
1354                 bond_info->unbalanced_load += skb->len;
1355         }
1356
1357         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1358                 if (tx_slave != bond->curr_active_slave) {
1359                         memcpy(eth_data->h_source,
1360                                tx_slave->dev->dev_addr,
1361                                ETH_ALEN);
1362                 }
1363
1364                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1365         } else {
1366                 if (tx_slave) {
1367                         tlb_clear_slave(bond, tx_slave, 0);
1368                 }
1369         }
1370
1371 out:
1372         if (res) {
1373                 /* no suitable interface, frame not sent */
1374                 dev_kfree_skb(skb);
1375         }
1376         read_unlock(&bond->curr_slave_lock);
1377         read_unlock(&bond->lock);
1378         return 0;
1379 }
1380
1381 void bond_alb_monitor(struct bonding *bond)
1382 {
1383         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1384         struct slave *slave;
1385         int i;
1386
1387         read_lock(&bond->lock);
1388
1389         if (bond->kill_timers) {
1390                 goto out;
1391         }
1392
1393         if (bond->slave_cnt == 0) {
1394                 bond_info->tx_rebalance_counter = 0;
1395                 bond_info->lp_counter = 0;
1396                 goto re_arm;
1397         }
1398
1399         bond_info->tx_rebalance_counter++;
1400         bond_info->lp_counter++;
1401
1402         /* send learning packets */
1403         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1404                 /* change of curr_active_slave involves swapping of mac addresses.
1405                  * in order to avoid this swapping from happening while
1406                  * sending the learning packets, the curr_slave_lock must be held for
1407                  * read.
1408                  */
1409                 read_lock(&bond->curr_slave_lock);
1410
1411                 bond_for_each_slave(bond, slave, i) {
1412                         alb_send_learning_packets(slave,slave->dev->dev_addr);
1413                 }
1414
1415                 read_unlock(&bond->curr_slave_lock);
1416
1417                 bond_info->lp_counter = 0;
1418         }
1419
1420         /* rebalance tx traffic */
1421         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1422
1423                 read_lock(&bond->curr_slave_lock);
1424
1425                 bond_for_each_slave(bond, slave, i) {
1426                         tlb_clear_slave(bond, slave, 1);
1427                         if (slave == bond->curr_active_slave) {
1428                                 SLAVE_TLB_INFO(slave).load =
1429                                         bond_info->unbalanced_load /
1430                                                 BOND_TLB_REBALANCE_INTERVAL;
1431                                 bond_info->unbalanced_load = 0;
1432                         }
1433                 }
1434
1435                 read_unlock(&bond->curr_slave_lock);
1436
1437                 bond_info->tx_rebalance_counter = 0;
1438         }
1439
1440         /* handle rlb stuff */
1441         if (bond_info->rlb_enabled) {
1442                 /* the following code changes the promiscuity of the
1443                  * the curr_active_slave. It needs to be locked with a
1444                  * write lock to protect from other code that also
1445                  * sets the promiscuity.
1446                  */
1447                 write_lock(&bond->curr_slave_lock);
1448
1449                 if (bond_info->primary_is_promisc &&
1450                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1451
1452                         bond_info->rlb_promisc_timeout_counter = 0;
1453
1454                         /* If the primary was set to promiscuous mode
1455                          * because a slave was disabled then
1456                          * it can now leave promiscuous mode.
1457                          */
1458                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1459                         bond_info->primary_is_promisc = 0;
1460                 }
1461
1462                 write_unlock(&bond->curr_slave_lock);
1463
1464                 if (bond_info->rlb_rebalance) {
1465                         bond_info->rlb_rebalance = 0;
1466                         rlb_rebalance(bond);
1467                 }
1468
1469                 /* check if clients need updating */
1470                 if (bond_info->rx_ntt) {
1471                         if (bond_info->rlb_update_delay_counter) {
1472                                 --bond_info->rlb_update_delay_counter;
1473                         } else {
1474                                 rlb_update_rx_clients(bond);
1475                                 if (bond_info->rlb_update_retry_counter) {
1476                                         --bond_info->rlb_update_retry_counter;
1477                                 } else {
1478                                         bond_info->rx_ntt = 0;
1479                                 }
1480                         }
1481                 }
1482         }
1483
1484 re_arm:
1485         mod_timer(&(bond_info->alb_timer), jiffies + alb_delta_in_ticks);
1486 out:
1487         read_unlock(&bond->lock);
1488 }
1489
1490 /* assumption: called before the slave is attached to the bond
1491  * and not locked by the bond lock
1492  */
1493 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1494 {
1495         int res;
1496
1497         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1498                                      bond->alb_info.rlb_enabled);
1499         if (res) {
1500                 return res;
1501         }
1502
1503         /* caller must hold the bond lock for write since the mac addresses
1504          * are compared and may be swapped.
1505          */
1506         write_lock_bh(&bond->lock);
1507
1508         res = alb_handle_addr_collision_on_attach(bond, slave);
1509
1510         write_unlock_bh(&bond->lock);
1511
1512         if (res) {
1513                 return res;
1514         }
1515
1516         tlb_init_slave(slave);
1517
1518         /* order a rebalance ASAP */
1519         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1520
1521         if (bond->alb_info.rlb_enabled) {
1522                 bond->alb_info.rlb_rebalance = 1;
1523         }
1524
1525         return 0;
1526 }
1527
1528 /* Caller must hold bond lock for write */
1529 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1530 {
1531         if (bond->slave_cnt > 1) {
1532                 alb_change_hw_addr_on_detach(bond, slave);
1533         }
1534
1535         tlb_clear_slave(bond, slave, 0);
1536
1537         if (bond->alb_info.rlb_enabled) {
1538                 bond->alb_info.next_rx_slave = NULL;
1539                 rlb_clear_slave(bond, slave);
1540         }
1541 }
1542
1543 /* Caller must hold bond lock for read */
1544 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1545 {
1546         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1547
1548         if (link == BOND_LINK_DOWN) {
1549                 tlb_clear_slave(bond, slave, 0);
1550                 if (bond->alb_info.rlb_enabled) {
1551                         rlb_clear_slave(bond, slave);
1552                 }
1553         } else if (link == BOND_LINK_UP) {
1554                 /* order a rebalance ASAP */
1555                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1556                 if (bond->alb_info.rlb_enabled) {
1557                         bond->alb_info.rlb_rebalance = 1;
1558                         /* If the updelay module parameter is smaller than the
1559                          * forwarding delay of the switch the rebalance will
1560                          * not work because the rebalance arp replies will
1561                          * not be forwarded to the clients..
1562                          */
1563                 }
1564         }
1565 }
1566
1567 /**
1568  * bond_alb_handle_active_change - assign new curr_active_slave
1569  * @bond: our bonding struct
1570  * @new_slave: new slave to assign
1571  *
1572  * Set the bond->curr_active_slave to @new_slave and handle
1573  * mac address swapping and promiscuity changes as needed.
1574  *
1575  * Caller must hold bond curr_slave_lock for write (or bond lock for write)
1576  */
1577 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1578 {
1579         struct slave *swap_slave;
1580         int i;
1581
1582         if (bond->curr_active_slave == new_slave) {
1583                 return;
1584         }
1585
1586         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1587                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1588                 bond->alb_info.primary_is_promisc = 0;
1589                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1590         }
1591
1592         swap_slave = bond->curr_active_slave;
1593         bond->curr_active_slave = new_slave;
1594
1595         if (!new_slave || (bond->slave_cnt == 0)) {
1596                 return;
1597         }
1598
1599         /* set the new curr_active_slave to the bonds mac address
1600          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1601          */
1602         if (!swap_slave) {
1603                 struct slave *tmp_slave;
1604                 /* find slave that is holding the bond's mac address */
1605                 bond_for_each_slave(bond, tmp_slave, i) {
1606                         if (!memcmp(tmp_slave->dev->dev_addr,
1607                                     bond->dev->dev_addr, ETH_ALEN)) {
1608                                 swap_slave = tmp_slave;
1609                                 break;
1610                         }
1611                 }
1612         }
1613
1614         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1615         if (swap_slave) {
1616                 /* swap mac address */
1617                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1618         } else {
1619                 /* set the new_slave to the bond mac address */
1620                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1621                                        bond->alb_info.rlb_enabled);
1622                 /* fasten bond mac on new current slave */
1623                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1624         }
1625 }
1626
1627 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1628 {
1629         struct bonding *bond = bond_dev->priv;
1630         struct sockaddr *sa = addr;
1631         struct slave *slave, *swap_slave;
1632         int res;
1633         int i;
1634
1635         if (!is_valid_ether_addr(sa->sa_data)) {
1636                 return -EADDRNOTAVAIL;
1637         }
1638
1639         res = alb_set_mac_address(bond, addr);
1640         if (res) {
1641                 return res;
1642         }
1643
1644         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1645
1646         /* If there is no curr_active_slave there is nothing else to do.
1647          * Otherwise we'll need to pass the new address to it and handle
1648          * duplications.
1649          */
1650         if (!bond->curr_active_slave) {
1651                 return 0;
1652         }
1653
1654         swap_slave = NULL;
1655
1656         bond_for_each_slave(bond, slave, i) {
1657                 if (!memcmp(slave->dev->dev_addr, bond_dev->dev_addr, ETH_ALEN)) {
1658                         swap_slave = slave;
1659                         break;
1660                 }
1661         }
1662
1663         if (swap_slave) {
1664                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1665         } else {
1666                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1667                                        bond->alb_info.rlb_enabled);
1668
1669                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1670                 if (bond->alb_info.rlb_enabled) {
1671                         /* inform clients mac address has changed */
1672                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1673                 }
1674         }
1675
1676         return 0;
1677 }
1678
1679 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1680 {
1681         if (bond->alb_info.current_alb_vlan &&
1682             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1683                 bond->alb_info.current_alb_vlan = NULL;
1684         }
1685
1686         if (bond->alb_info.rlb_enabled) {
1687                 rlb_clear_vlan(bond, vlan_id);
1688         }
1689 }
1690