git.oblomov.eu Git - linux-2.6/blob - drivers/net/bonding/bond_alb.c

   1 /*
   2  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License as published by the
   6  * Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  */
  22
  23 //#define BONDING_DEBUG 1
  24
  25 #include <linux/skbuff.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/pkt_sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/slab.h>
  31 #include <linux/timer.h>
  32 #include <linux/ip.h>
  33 #include <linux/ipv6.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/if_ether.h>
  36 #include <linux/if_bonding.h>
  37 #include <linux/if_vlan.h>
  38 #include <linux/in.h>
  39 #include <net/ipx.h>
  40 #include <net/arp.h>
  41 #include <asm/byteorder.h>
  42 #include "bonding.h"
  43 #include "bond_alb.h"
  44
  45
  46 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
  47 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
  48                                          * Used for division - never set
  49                                          * to zero !!!
  50                                          */
  51 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
  52                                          * learning packets to the switch
  53                                          */
  54
  55 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
  56                                   * ALB_TIMER_TICKS_PER_SEC)
  57
  58 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
  59                            * ALB_TIMER_TICKS_PER_SEC)
  60
  61 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
  62                                  * Note that this value MUST NOT be smaller
  63                                  * because the key hash table is BYTE wide !
  64                                  */
  65
  66
  67 #define TLB_NULL_INDEX          0xffffffff
  68 #define MAX_LP_BURST            3
  69
  70 /* rlb defs */
  71 #define RLB_HASH_TABLE_SIZE     256
  72 #define RLB_NULL_INDEX          0xffffffff
  73 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
  74 #define RLB_ARP_BURST_SIZE      2
  75 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
  76                                          * rebalance interval (5 min).
  77                                          */
  78 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
  79  * promiscuous after failover
  80  */
  81 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
  82
  83 static const u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
  84 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  85
  86 #pragma pack(1)
  87 struct learning_pkt {
  88         u8 mac_dst[ETH_ALEN];
  89         u8 mac_src[ETH_ALEN];
  90         u16 type;
  91         u8 padding[ETH_ZLEN - ETH_HLEN];
  92 };
  93
  94 struct arp_pkt {
  95         u16     hw_addr_space;
  96         u16     prot_addr_space;
  97         u8      hw_addr_len;
  98         u8      prot_addr_len;
  99         u16     op_code;
 100         u8      mac_src[ETH_ALEN];      /* sender hardware address */
 101         u32     ip_src;                 /* sender IP address */
 102         u8      mac_dst[ETH_ALEN];      /* target hardware address */
 103         u32     ip_dst;                 /* target IP address */
 104 };
 105 #pragma pack()
 106
 107 /* Forward declaration */
 108 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
 109
 110 static inline u8 _simple_hash(u8 *hash_start, int hash_size)
 111 {
 112         int i;
 113         u8 hash = 0;
 114
 115         for (i = 0; i < hash_size; i++) {
 116                 hash ^= hash_start[i];
 117         }
 118
 119         return hash;
 120 }
 121
 122 /*********************** tlb specific functions ***************************/
 123
 124 static inline void _lock_tx_hashtbl(struct bonding *bond)
 125 {
 126         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 127 }
 128
 129 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 130 {
 131         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 132 }
 133
 134 /* Caller must hold tx_hashtbl lock */
 135 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 136 {
 137         if (save_load) {
 138                 entry->load_history = 1 + entry->tx_bytes /
 139                                       BOND_TLB_REBALANCE_INTERVAL;
 140                 entry->tx_bytes = 0;
 141         }
 142
 143         entry->tx_slave = NULL;
 144         entry->next = TLB_NULL_INDEX;
 145         entry->prev = TLB_NULL_INDEX;
 146 }
 147
 148 static inline void tlb_init_slave(struct slave *slave)
 149 {
 150         SLAVE_TLB_INFO(slave).load = 0;
 151         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 152 }
 153
 154 /* Caller must hold bond lock for read */
 155 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
 156 {
 157         struct tlb_client_info *tx_hash_table;
 158         u32 index;
 159
 160         _lock_tx_hashtbl(bond);
 161
 162         /* clear slave from tx_hashtbl */
 163         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 164
 165         index = SLAVE_TLB_INFO(slave).head;
 166         while (index != TLB_NULL_INDEX) {
 167                 u32 next_index = tx_hash_table[index].next;
 168                 tlb_init_table_entry(&tx_hash_table[index], save_load);
 169                 index = next_index;
 170         }
 171
 172         tlb_init_slave(slave);
 173
 174         _unlock_tx_hashtbl(bond);
 175 }
 176
 177 /* Must be called before starting the monitor timer */
 178 static int tlb_initialize(struct bonding *bond)
 179 {
 180         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 181         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 182         struct tlb_client_info *new_hashtbl;
 183         int i;
 184
 185         spin_lock_init(&(bond_info->tx_hashtbl_lock));
 186
 187         new_hashtbl = kmalloc(size, GFP_KERNEL);
 188         if (!new_hashtbl) {
 189                 printk(KERN_ERR DRV_NAME
 190                        ": %s: Error: Failed to allocate TLB hash table\n",
 191                        bond->dev->name);
 192                 return -1;
 193         }
 194         _lock_tx_hashtbl(bond);
 195
 196         bond_info->tx_hashtbl = new_hashtbl;
 197
 198         memset(bond_info->tx_hashtbl, 0, size);
 199
 200         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 201                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
 202         }
 203
 204         _unlock_tx_hashtbl(bond);
 205
 206         return 0;
 207 }
 208
 209 /* Must be called only after all slaves have been released */
 210 static void tlb_deinitialize(struct bonding *bond)
 211 {
 212         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 213
 214         _lock_tx_hashtbl(bond);
 215
 216         kfree(bond_info->tx_hashtbl);
 217         bond_info->tx_hashtbl = NULL;
 218
 219         _unlock_tx_hashtbl(bond);
 220 }
 221
 222 /* Caller must hold bond lock for read */
 223 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 224 {
 225         struct slave *slave, *least_loaded;
 226         s64 max_gap;
 227         int i, found = 0;
 228
 229         /* Find the first enabled slave */
 230         bond_for_each_slave(bond, slave, i) {
 231                 if (SLAVE_IS_OK(slave)) {
 232                         found = 1;
 233                         break;
 234                 }
 235         }
 236
 237         if (!found) {
 238                 return NULL;
 239         }
 240
 241         least_loaded = slave;
 242         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
 243                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 244
 245         /* Find the slave with the largest gap */
 246         bond_for_each_slave_from(bond, slave, i, least_loaded) {
 247                 if (SLAVE_IS_OK(slave)) {
 248                         s64 gap = (s64)(slave->speed << 20) -
 249                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
 250                         if (max_gap < gap) {
 251                                 least_loaded = slave;
 252                                 max_gap = gap;
 253                         }
 254                 }
 255         }
 256
 257         return least_loaded;
 258 }
 259
 260 /* Caller must hold bond lock for read */
 261 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
 262 {
 263         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 264         struct tlb_client_info *hash_table;
 265         struct slave *assigned_slave;
 266
 267         _lock_tx_hashtbl(bond);
 268
 269         hash_table = bond_info->tx_hashtbl;
 270         assigned_slave = hash_table[hash_index].tx_slave;
 271         if (!assigned_slave) {
 272                 assigned_slave = tlb_get_least_loaded_slave(bond);
 273
 274                 if (assigned_slave) {
 275                         struct tlb_slave_info *slave_info =
 276                                 &(SLAVE_TLB_INFO(assigned_slave));
 277                         u32 next_index = slave_info->head;
 278
 279                         hash_table[hash_index].tx_slave = assigned_slave;
 280                         hash_table[hash_index].next = next_index;
 281                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 282
 283                         if (next_index != TLB_NULL_INDEX) {
 284                                 hash_table[next_index].prev = hash_index;
 285                         }
 286
 287                         slave_info->head = hash_index;
 288                         slave_info->load +=
 289                                 hash_table[hash_index].load_history;
 290                 }
 291         }
 292
 293         if (assigned_slave) {
 294                 hash_table[hash_index].tx_bytes += skb_len;
 295         }
 296
 297         _unlock_tx_hashtbl(bond);
 298
 299         return assigned_slave;
 300 }
 301
 302 /*********************** rlb specific functions ***************************/
 303 static inline void _lock_rx_hashtbl(struct bonding *bond)
 304 {
 305         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 306 }
 307
 308 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 309 {
 310         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 311 }
 312
 313 /* when an ARP REPLY is received from a client update its info
 314  * in the rx_hashtbl
 315  */
 316 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 317 {
 318         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 319         struct rlb_client_info *client_info;
 320         u32 hash_index;
 321
 322         _lock_rx_hashtbl(bond);
 323
 324         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 325         client_info = &(bond_info->rx_hashtbl[hash_index]);
 326
 327         if ((client_info->assigned) &&
 328             (client_info->ip_src == arp->ip_dst) &&
 329             (client_info->ip_dst == arp->ip_src)) {
 330                 /* update the clients MAC address */
 331                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 332                 client_info->ntt = 1;
 333                 bond_info->rx_ntt = 1;
 334         }
 335
 336         _unlock_rx_hashtbl(bond);
 337 }
 338
 339 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype, struct net_device *orig_dev)
 340 {
 341         struct bonding *bond = bond_dev->priv;
 342         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
 343         int res = NET_RX_DROP;
 344
 345         if (!(bond_dev->flags & IFF_MASTER))
 346                 goto out;
 347
 348         if (!arp) {
 349                 dprintk("Packet has no ARP data\n");
 350                 goto out;
 351         }
 352
 353         if (skb->len < sizeof(struct arp_pkt)) {
 354                 dprintk("Packet is too small to be an ARP\n");
 355                 goto out;
 356         }
 357
 358         if (arp->op_code == htons(ARPOP_REPLY)) {
 359                 /* update rx hash table for this ARP */
 360                 rlb_update_entry_from_arp(bond, arp);
 361                 dprintk("Server received an ARP Reply from client\n");
 362         }
 363
 364         res = NET_RX_SUCCESS;
 365
 366 out:
 367         dev_kfree_skb(skb);
 368
 369         return res;
 370 }
 371
 372 /* Caller must hold bond lock for read */
 373 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 374 {
 375         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 376         struct slave *rx_slave, *slave, *start_at;
 377         int i = 0;
 378
 379         if (bond_info->next_rx_slave) {
 380                 start_at = bond_info->next_rx_slave;
 381         } else {
 382                 start_at = bond->first_slave;
 383         }
 384
 385         rx_slave = NULL;
 386
 387         bond_for_each_slave_from(bond, slave, i, start_at) {
 388                 if (SLAVE_IS_OK(slave)) {
 389                         if (!rx_slave) {
 390                                 rx_slave = slave;
 391                         } else if (slave->speed > rx_slave->speed) {
 392                                 rx_slave = slave;
 393                         }
 394                 }
 395         }
 396
 397         if (rx_slave) {
 398                 bond_info->next_rx_slave = rx_slave->next;
 399         }
 400
 401         return rx_slave;
 402 }
 403
 404 /* teach the switch the mac of a disabled slave
 405  * on the primary for fault tolerance
 406  *
 407  * Caller must hold bond->curr_slave_lock for write or bond lock for write
 408  */
 409 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 410 {
 411         if (!bond->curr_active_slave) {
 412                 return;
 413         }
 414
 415         if (!bond->alb_info.primary_is_promisc) {
 416                 bond->alb_info.primary_is_promisc = 1;
 417                 dev_set_promiscuity(bond->curr_active_slave->dev, 1);
 418         }
 419
 420         bond->alb_info.rlb_promisc_timeout_counter = 0;
 421
 422         alb_send_learning_packets(bond->curr_active_slave, addr);
 423 }
 424
 425 /* slave being removed should not be active at this point
 426  *
 427  * Caller must hold bond lock for read
 428  */
 429 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 430 {
 431         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 432         struct rlb_client_info *rx_hash_table;
 433         u32 index, next_index;
 434
 435         /* clear slave from rx_hashtbl */
 436         _lock_rx_hashtbl(bond);
 437
 438         rx_hash_table = bond_info->rx_hashtbl;
 439         index = bond_info->rx_hashtbl_head;
 440         for (; index != RLB_NULL_INDEX; index = next_index) {
 441                 next_index = rx_hash_table[index].next;
 442                 if (rx_hash_table[index].slave == slave) {
 443                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 444
 445                         if (assigned_slave) {
 446                                 rx_hash_table[index].slave = assigned_slave;
 447                                 if (memcmp(rx_hash_table[index].mac_dst,
 448                                            mac_bcast, ETH_ALEN)) {
 449                                         bond_info->rx_hashtbl[index].ntt = 1;
 450                                         bond_info->rx_ntt = 1;
 451                                         /* A slave has been removed from the
 452                                          * table because it is either disabled
 453                                          * or being released. We must retry the
 454                                          * update to avoid clients from not
 455                                          * being updated & disconnecting when
 456                                          * there is stress
 457                                          */
 458                                         bond_info->rlb_update_retry_counter =
 459                                                 RLB_UPDATE_RETRY;
 460                                 }
 461                         } else {  /* there is no active slave */
 462                                 rx_hash_table[index].slave = NULL;
 463                         }
 464                 }
 465         }
 466
 467         _unlock_rx_hashtbl(bond);
 468
 469         write_lock(&bond->curr_slave_lock);
 470
 471         if (slave != bond->curr_active_slave) {
 472                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 473         }
 474
 475         write_unlock(&bond->curr_slave_lock);
 476 }
 477
 478 static void rlb_update_client(struct rlb_client_info *client_info)
 479 {
 480         int i;
 481
 482         if (!client_info->slave) {
 483                 return;
 484         }
 485
 486         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 487                 struct sk_buff *skb;
 488
 489                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 490                                  client_info->ip_dst,
 491                                  client_info->slave->dev,
 492                                  client_info->ip_src,
 493                                  client_info->mac_dst,
 494                                  client_info->slave->dev->dev_addr,
 495                                  client_info->mac_dst);
 496                 if (!skb) {
 497                         printk(KERN_ERR DRV_NAME
 498                                ": %s: Error: failed to create an ARP packet\n",
 499                                client_info->slave->dev->master->name);
 500                         continue;
 501                 }
 502
 503                 skb->dev = client_info->slave->dev;
 504
 505                 if (client_info->tag) {
 506                         skb = vlan_put_tag(skb, client_info->vlan_id);
 507                         if (!skb) {
 508                                 printk(KERN_ERR DRV_NAME
 509                                        ": %s: Error: failed to insert VLAN tag\n",
 510                                        client_info->slave->dev->master->name);
 511                                 continue;
 512                         }
 513                 }
 514
 515                 arp_xmit(skb);
 516         }
 517 }
 518
 519 /* sends ARP REPLIES that update the clients that need updating */
 520 static void rlb_update_rx_clients(struct bonding *bond)
 521 {
 522         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 523         struct rlb_client_info *client_info;
 524         u32 hash_index;
 525
 526         _lock_rx_hashtbl(bond);
 527
 528         hash_index = bond_info->rx_hashtbl_head;
 529         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 530                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 531                 if (client_info->ntt) {
 532                         rlb_update_client(client_info);
 533                         if (bond_info->rlb_update_retry_counter == 0) {
 534                                 client_info->ntt = 0;
 535                         }
 536                 }
 537         }
 538
 539         /* do not update the entries again untill this counter is zero so that
 540          * not to confuse the clients.
 541          */
 542         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 543
 544         _unlock_rx_hashtbl(bond);
 545 }
 546
 547 /* The slave was assigned a new mac address - update the clients */
 548 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 549 {
 550         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 551         struct rlb_client_info *client_info;
 552         int ntt = 0;
 553         u32 hash_index;
 554
 555         _lock_rx_hashtbl(bond);
 556
 557         hash_index = bond_info->rx_hashtbl_head;
 558         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 559                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 560
 561                 if ((client_info->slave == slave) &&
 562                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 563                         client_info->ntt = 1;
 564                         ntt = 1;
 565                 }
 566         }
 567
 568         // update the team's flag only after the whole iteration
 569         if (ntt) {
 570                 bond_info->rx_ntt = 1;
 571                 //fasten the change
 572                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 573         }
 574
 575         _unlock_rx_hashtbl(bond);
 576 }
 577
 578 /* mark all clients using src_ip to be updated */
 579 static void rlb_req_update_subnet_clients(struct bonding *bond, u32 src_ip)
 580 {
 581         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 582         struct rlb_client_info *client_info;
 583         u32 hash_index;
 584
 585         _lock_rx_hashtbl(bond);
 586
 587         hash_index = bond_info->rx_hashtbl_head;
 588         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 589                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 590
 591                 if (!client_info->slave) {
 592                         printk(KERN_ERR DRV_NAME
 593                                ": %s: Error: found a client with no channel in "
 594                                "the client's hash table\n",
 595                                bond->dev->name);
 596                         continue;
 597                 }
 598                 /*update all clients using this src_ip, that are not assigned
 599                  * to the team's address (curr_active_slave) and have a known
 600                  * unicast mac address.
 601                  */
 602                 if ((client_info->ip_src == src_ip) &&
 603                     memcmp(client_info->slave->dev->dev_addr,
 604                            bond->dev->dev_addr, ETH_ALEN) &&
 605                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 606                         client_info->ntt = 1;
 607                         bond_info->rx_ntt = 1;
 608                 }
 609         }
 610
 611         _unlock_rx_hashtbl(bond);
 612 }
 613
 614 /* Caller must hold both bond and ptr locks for read */
 615 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 616 {
 617         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 618         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
 619         struct slave *assigned_slave;
 620         struct rlb_client_info *client_info;
 621         u32 hash_index = 0;
 622
 623         _lock_rx_hashtbl(bond);
 624
 625         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_src));
 626         client_info = &(bond_info->rx_hashtbl[hash_index]);
 627
 628         if (client_info->assigned) {
 629                 if ((client_info->ip_src == arp->ip_src) &&
 630                     (client_info->ip_dst == arp->ip_dst)) {
 631                         /* the entry is already assigned to this client */
 632                         if (memcmp(arp->mac_dst, mac_bcast, ETH_ALEN)) {
 633                                 /* update mac address from arp */
 634                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 635                         }
 636
 637                         assigned_slave = client_info->slave;
 638                         if (assigned_slave) {
 639                                 _unlock_rx_hashtbl(bond);
 640                                 return assigned_slave;
 641                         }
 642                 } else {
 643                         /* the entry is already assigned to some other client,
 644                          * move the old client to primary (curr_active_slave) so
 645                          * that the new client can be assigned to this entry.
 646                          */
 647                         if (bond->curr_active_slave &&
 648                             client_info->slave != bond->curr_active_slave) {
 649                                 client_info->slave = bond->curr_active_slave;
 650                                 rlb_update_client(client_info);
 651                         }
 652                 }
 653         }
 654         /* assign a new slave */
 655         assigned_slave = rlb_next_rx_slave(bond);
 656
 657         if (assigned_slave) {
 658                 client_info->ip_src = arp->ip_src;
 659                 client_info->ip_dst = arp->ip_dst;
 660                 /* arp->mac_dst is broadcast for arp reqeusts.
 661                  * will be updated with clients actual unicast mac address
 662                  * upon receiving an arp reply.
 663                  */
 664                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
 665                 client_info->slave = assigned_slave;
 666
 667                 if (memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
 668                         client_info->ntt = 1;
 669                         bond->alb_info.rx_ntt = 1;
 670                 } else {
 671                         client_info->ntt = 0;
 672                 }
 673
 674                 if (!list_empty(&bond->vlan_list)) {
 675                         unsigned short vlan_id;
 676                         int res = vlan_get_tag(skb, &vlan_id);
 677                         if (!res) {
 678                                 client_info->tag = 1;
 679                                 client_info->vlan_id = vlan_id;
 680                         }
 681                 }
 682
 683                 if (!client_info->assigned) {
 684                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
 685                         bond_info->rx_hashtbl_head = hash_index;
 686                         client_info->next = prev_tbl_head;
 687                         if (prev_tbl_head != RLB_NULL_INDEX) {
 688                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
 689                                         hash_index;
 690                         }
 691                         client_info->assigned = 1;
 692                 }
 693         }
 694
 695         _unlock_rx_hashtbl(bond);
 696
 697         return assigned_slave;
 698 }
 699
 700 /* chooses (and returns) transmit channel for arp reply
 701  * does not choose channel for other arp types since they are
 702  * sent on the curr_active_slave
 703  */
 704 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 705 {
 706         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
 707         struct slave *tx_slave = NULL;
 708
 709         if (arp->op_code == __constant_htons(ARPOP_REPLY)) {
 710                 /* the arp must be sent on the selected
 711                 * rx channel
 712                 */
 713                 tx_slave = rlb_choose_channel(skb, bond);
 714                 if (tx_slave) {
 715                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
 716                 }
 717                 dprintk("Server sent ARP Reply packet\n");
 718         } else if (arp->op_code == __constant_htons(ARPOP_REQUEST)) {
 719                 /* Create an entry in the rx_hashtbl for this client as a
 720                  * place holder.
 721                  * When the arp reply is received the entry will be updated
 722                  * with the correct unicast address of the client.
 723                  */
 724                 rlb_choose_channel(skb, bond);
 725
 726                 /* The ARP relpy packets must be delayed so that
 727                  * they can cancel out the influence of the ARP request.
 728                  */
 729                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 730
 731                 /* arp requests are broadcast and are sent on the primary
 732                  * the arp request will collapse all clients on the subnet to
 733                  * the primary slave. We must register these clients to be
 734                  * updated with their assigned mac.
 735                  */
 736                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 737                 dprintk("Server sent ARP Request packet\n");
 738         }
 739
 740         return tx_slave;
 741 }
 742
 743 /* Caller must hold bond lock for read */
 744 static void rlb_rebalance(struct bonding *bond)
 745 {
 746         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 747         struct slave *assigned_slave;
 748         struct rlb_client_info *client_info;
 749         int ntt;
 750         u32 hash_index;
 751
 752         _lock_rx_hashtbl(bond);
 753
 754         ntt = 0;
 755         hash_index = bond_info->rx_hashtbl_head;
 756         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 757                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 758                 assigned_slave = rlb_next_rx_slave(bond);
 759                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 760                         client_info->slave = assigned_slave;
 761                         client_info->ntt = 1;
 762                         ntt = 1;
 763                 }
 764         }
 765
 766         /* update the team's flag only after the whole iteration */
 767         if (ntt) {
 768                 bond_info->rx_ntt = 1;
 769         }
 770         _unlock_rx_hashtbl(bond);
 771 }
 772
 773 /* Caller must hold rx_hashtbl lock */
 774 static void rlb_init_table_entry(struct rlb_client_info *entry)
 775 {
 776         memset(entry, 0, sizeof(struct rlb_client_info));
 777         entry->next = RLB_NULL_INDEX;
 778         entry->prev = RLB_NULL_INDEX;
 779 }
 780
 781 static int rlb_initialize(struct bonding *bond)
 782 {
 783         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 784         struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
 785         struct rlb_client_info  *new_hashtbl;
 786         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 787         int i;
 788
 789         spin_lock_init(&(bond_info->rx_hashtbl_lock));
 790
 791         new_hashtbl = kmalloc(size, GFP_KERNEL);
 792         if (!new_hashtbl) {
 793                 printk(KERN_ERR DRV_NAME
 794                        ": %s: Error: Failed to allocate RLB hash table\n",
 795                        bond->dev->name);
 796                 return -1;
 797         }
 798         _lock_rx_hashtbl(bond);
 799
 800         bond_info->rx_hashtbl = new_hashtbl;
 801
 802         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 803
 804         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
 805                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 806         }
 807
 808         _unlock_rx_hashtbl(bond);
 809
 810         /*initialize packet type*/
 811         pk_type->type = __constant_htons(ETH_P_ARP);
 812         pk_type->dev = bond->dev;
 813         pk_type->func = rlb_arp_recv;
 814
 815         /* register to receive ARPs */
 816         dev_add_pack(pk_type);
 817
 818         return 0;
 819 }
 820
 821 static void rlb_deinitialize(struct bonding *bond)
 822 {
 823         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 824
 825         dev_remove_pack(&(bond_info->rlb_pkt_type));
 826
 827         _lock_rx_hashtbl(bond);
 828
 829         kfree(bond_info->rx_hashtbl);
 830         bond_info->rx_hashtbl = NULL;
 831         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 832
 833         _unlock_rx_hashtbl(bond);
 834 }
 835
 836 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 837 {
 838         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 839         u32 curr_index;
 840
 841         _lock_rx_hashtbl(bond);
 842
 843         curr_index = bond_info->rx_hashtbl_head;
 844         while (curr_index != RLB_NULL_INDEX) {
 845                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 846                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
 847                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
 848
 849                 if (curr->tag && (curr->vlan_id == vlan_id)) {
 850                         if (curr_index == bond_info->rx_hashtbl_head) {
 851                                 bond_info->rx_hashtbl_head = next_index;
 852                         }
 853                         if (prev_index != RLB_NULL_INDEX) {
 854                                 bond_info->rx_hashtbl[prev_index].next = next_index;
 855                         }
 856                         if (next_index != RLB_NULL_INDEX) {
 857                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
 858                         }
 859
 860                         rlb_init_table_entry(curr);
 861                 }
 862
 863                 curr_index = next_index;
 864         }
 865
 866         _unlock_rx_hashtbl(bond);
 867 }
 868
 869 /*********************** tlb/rlb shared functions *********************/
 870
 871 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
 872 {
 873         struct bonding *bond = bond_get_bond_by_slave(slave);
 874         struct learning_pkt pkt;
 875         int size = sizeof(struct learning_pkt);
 876         int i;
 877
 878         memset(&pkt, 0, size);
 879         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
 880         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
 881         pkt.type = __constant_htons(ETH_P_LOOP);
 882
 883         for (i = 0; i < MAX_LP_BURST; i++) {
 884                 struct sk_buff *skb;
 885                 char *data;
 886
 887                 skb = dev_alloc_skb(size);
 888                 if (!skb) {
 889                         return;
 890                 }
 891
 892                 data = skb_put(skb, size);
 893                 memcpy(data, &pkt, size);
 894
 895                 skb->mac.raw = data;
 896                 skb->nh.raw = data + ETH_HLEN;
 897                 skb->protocol = pkt.type;
 898                 skb->priority = TC_PRIO_CONTROL;
 899                 skb->dev = slave->dev;
 900
 901                 if (!list_empty(&bond->vlan_list)) {
 902                         struct vlan_entry *vlan;
 903
 904                         vlan = bond_next_vlan(bond,
 905                                               bond->alb_info.current_alb_vlan);
 906
 907                         bond->alb_info.current_alb_vlan = vlan;
 908                         if (!vlan) {
 909                                 kfree_skb(skb);
 910                                 continue;
 911                         }
 912
 913                         skb = vlan_put_tag(skb, vlan->vlan_id);
 914                         if (!skb) {
 915                                 printk(KERN_ERR DRV_NAME
 916                                        ": %s: Error: failed to insert VLAN tag\n",
 917                                        bond->dev->name);
 918                                 continue;
 919                         }
 920                 }
 921
 922                 dev_queue_xmit(skb);
 923         }
 924 }
 925
 926 /* hw is a boolean parameter that determines whether we should try and
 927  * set the hw address of the device as well as the hw address of the
 928  * net_device
 929  */
 930 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
 931 {
 932         struct net_device *dev = slave->dev;
 933         struct sockaddr s_addr;
 934
 935         if (!hw) {
 936                 memcpy(dev->dev_addr, addr, dev->addr_len);
 937                 return 0;
 938         }
 939
 940         /* for rlb each slave must have a unique hw mac addresses so that */
 941         /* each slave will receive packets destined to a different mac */
 942         memcpy(s_addr.sa_data, addr, dev->addr_len);
 943         s_addr.sa_family = dev->type;
 944         if (dev_set_mac_address(dev, &s_addr)) {
 945                 printk(KERN_ERR DRV_NAME
 946                        ": %s: Error: dev_set_mac_address of dev %s failed! ALB "
 947                        "mode requires that the base driver support setting "
 948                        "the hw address also when the network device's "
 949                        "interface is open\n",
 950                        dev->master->name, dev->name);
 951                 return -EOPNOTSUPP;
 952         }
 953         return 0;
 954 }
 955
 956 /* Caller must hold bond lock for write or curr_slave_lock for write*/
 957 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
 958 {
 959         struct slave *disabled_slave = NULL;
 960         u8 tmp_mac_addr[ETH_ALEN];
 961         int slaves_state_differ;
 962
 963         slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
 964
 965         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
 966         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
 967         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
 968
 969         /* fasten the change in the switch */
 970         if (SLAVE_IS_OK(slave1)) {
 971                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
 972                 if (bond->alb_info.rlb_enabled) {
 973                         /* inform the clients that the mac address
 974                          * has changed
 975                          */
 976                         rlb_req_update_slave_clients(bond, slave1);
 977                 }
 978         } else {
 979                 disabled_slave = slave1;
 980         }
 981
 982         if (SLAVE_IS_OK(slave2)) {
 983                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
 984                 if (bond->alb_info.rlb_enabled) {
 985                         /* inform the clients that the mac address
 986                          * has changed
 987                          */
 988                         rlb_req_update_slave_clients(bond, slave2);
 989                 }
 990         } else {
 991                 disabled_slave = slave2;
 992         }
 993
 994         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
 995                 /* A disabled slave was assigned an active mac addr */
 996                 rlb_teach_disabled_mac_on_primary(bond,
 997                                                   disabled_slave->dev->dev_addr);
 998         }
 999 }
1000
1001 /**
1002  * alb_change_hw_addr_on_detach
1003  * @bond: bonding we're working on
1004  * @slave: the slave that was just detached
1005  *
1006  * We assume that @slave was already detached from the slave list.
1007  *
1008  * If @slave's permanent hw address is different both from its current
1009  * address and from @bond's address, then somewhere in the bond there's
1010  * a slave that has @slave's permanet address as its current address.
1011  * We'll make sure that that slave no longer uses @slave's permanent address.
1012  *
1013  * Caller must hold bond lock
1014  */
1015 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1016 {
1017         int perm_curr_diff;
1018         int perm_bond_diff;
1019
1020         perm_curr_diff = memcmp(slave->perm_hwaddr,
1021                                 slave->dev->dev_addr,
1022                                 ETH_ALEN);
1023         perm_bond_diff = memcmp(slave->perm_hwaddr,
1024                                 bond->dev->dev_addr,
1025                                 ETH_ALEN);
1026
1027         if (perm_curr_diff && perm_bond_diff) {
1028                 struct slave *tmp_slave;
1029                 int i, found = 0;
1030
1031                 bond_for_each_slave(bond, tmp_slave, i) {
1032                         if (!memcmp(slave->perm_hwaddr,
1033                                     tmp_slave->dev->dev_addr,
1034                                     ETH_ALEN)) {
1035                                 found = 1;
1036                                 break;
1037                         }
1038                 }
1039
1040                 if (found) {
1041                         alb_swap_mac_addr(bond, slave, tmp_slave);
1042                 }
1043         }
1044 }
1045
1046 /**
1047  * alb_handle_addr_collision_on_attach
1048  * @bond: bonding we're working on
1049  * @slave: the slave that was just attached
1050  *
1051  * checks uniqueness of slave's mac address and handles the case the
1052  * new slave uses the bonds mac address.
1053  *
1054  * If the permanent hw address of @slave is @bond's hw address, we need to
1055  * find a different hw address to give @slave, that isn't in use by any other
1056  * slave in the bond. This address must be, of course, one of the premanent
1057  * addresses of the other slaves.
1058  *
1059  * We go over the slave list, and for each slave there we compare its
1060  * permanent hw address with the current address of all the other slaves.
1061  * If no match was found, then we've found a slave with a permanent address
1062  * that isn't used by any other slave in the bond, so we can assign it to
1063  * @slave.
1064  *
1065  * assumption: this function is called before @slave is attached to the
1066  *             bond slave list.
1067  *
1068  * caller must hold the bond lock for write since the mac addresses are compared
1069  * and may be swapped.
1070  */
1071 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1072 {
1073         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1074         struct slave *has_bond_addr = bond->curr_active_slave;
1075         int i, j, found = 0;
1076
1077         if (bond->slave_cnt == 0) {
1078                 /* this is the first slave */
1079                 return 0;
1080         }
1081
1082         /* if slave's mac address differs from bond's mac address
1083          * check uniqueness of slave's mac address against the other
1084          * slaves in the bond.
1085          */
1086         if (memcmp(slave->perm_hwaddr, bond->dev->dev_addr, ETH_ALEN)) {
1087                 bond_for_each_slave(bond, tmp_slave1, i) {
1088                         if (!memcmp(tmp_slave1->dev->dev_addr, slave->dev->dev_addr,
1089                                     ETH_ALEN)) {
1090                                 found = 1;
1091                                 break;
1092                         }
1093                 }
1094
1095                 if (!found)
1096                         return 0;
1097
1098                 /* Try setting slave mac to bond address and fall-through
1099                    to code handling that situation below... */
1100                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1101                                        bond->alb_info.rlb_enabled);
1102         }
1103
1104         /* The slave's address is equal to the address of the bond.
1105          * Search for a spare address in the bond for this slave.
1106          */
1107         free_mac_slave = NULL;
1108
1109         bond_for_each_slave(bond, tmp_slave1, i) {
1110                 found = 0;
1111                 bond_for_each_slave(bond, tmp_slave2, j) {
1112                         if (!memcmp(tmp_slave1->perm_hwaddr,
1113                                     tmp_slave2->dev->dev_addr,
1114                                     ETH_ALEN)) {
1115                                 found = 1;
1116                                 break;
1117                         }
1118                 }
1119
1120                 if (!found) {
1121                         /* no slave has tmp_slave1's perm addr
1122                          * as its curr addr
1123                          */
1124                         free_mac_slave = tmp_slave1;
1125                         break;
1126                 }
1127
1128                 if (!has_bond_addr) {
1129                         if (!memcmp(tmp_slave1->dev->dev_addr,
1130                                     bond->dev->dev_addr,
1131                                     ETH_ALEN)) {
1132
1133                                 has_bond_addr = tmp_slave1;
1134                         }
1135                 }
1136         }
1137
1138         if (free_mac_slave) {
1139                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1140                                        bond->alb_info.rlb_enabled);
1141
1142                 printk(KERN_WARNING DRV_NAME
1143                        ": %s: Warning: the hw address of slave %s is in use by "
1144                        "the bond; giving it the hw address of %s\n",
1145                        bond->dev->name, slave->dev->name, free_mac_slave->dev->name);
1146
1147         } else if (has_bond_addr) {
1148                 printk(KERN_ERR DRV_NAME
1149                        ": %s: Error: the hw address of slave %s is in use by the "
1150                        "bond; couldn't find a slave with a free hw address to "
1151                        "give it (this should not have happened)\n",
1152                        bond->dev->name, slave->dev->name);
1153                 return -EFAULT;
1154         }
1155
1156         return 0;
1157 }
1158
1159 /**
1160  * alb_set_mac_address
1161  * @bond:
1162  * @addr:
1163  *
1164  * In TLB mode all slaves are configured to the bond's hw address, but set
1165  * their dev_addr field to different addresses (based on their permanent hw
1166  * addresses).
1167  *
1168  * For each slave, this function sets the interface to the new address and then
1169  * changes its dev_addr field to its previous value.
1170  *
1171  * Unwinding assumes bond's mac address has not yet changed.
1172  */
1173 static int alb_set_mac_address(struct bonding *bond, void *addr)
1174 {
1175         struct sockaddr sa;
1176         struct slave *slave, *stop_at;
1177         char tmp_addr[ETH_ALEN];
1178         int res;
1179         int i;
1180
1181         if (bond->alb_info.rlb_enabled) {
1182                 return 0;
1183         }
1184
1185         bond_for_each_slave(bond, slave, i) {
1186                 if (slave->dev->set_mac_address == NULL) {
1187                         res = -EOPNOTSUPP;
1188                         goto unwind;
1189                 }
1190
1191                 /* save net_device's current hw address */
1192                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1193
1194                 res = dev_set_mac_address(slave->dev, addr);
1195
1196                 /* restore net_device's hw address */
1197                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1198
1199                 if (res) {
1200                         goto unwind;
1201                 }
1202         }
1203
1204         return 0;
1205
1206 unwind:
1207         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1208         sa.sa_family = bond->dev->type;
1209
1210         /* unwind from head to the slave that failed */
1211         stop_at = slave;
1212         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1213                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1214                 dev_set_mac_address(slave->dev, &sa);
1215                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1216         }
1217
1218         return res;
1219 }
1220
1221 /************************ exported alb funcions ************************/
1222
1223 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1224 {
1225         int res;
1226
1227         res = tlb_initialize(bond);
1228         if (res) {
1229                 return res;
1230         }
1231
1232         if (rlb_enabled) {
1233                 bond->alb_info.rlb_enabled = 1;
1234                 /* initialize rlb */
1235                 res = rlb_initialize(bond);
1236                 if (res) {
1237                         tlb_deinitialize(bond);
1238                         return res;
1239                 }
1240         } else {
1241                 bond->alb_info.rlb_enabled = 0;
1242         }
1243
1244         return 0;
1245 }
1246
1247 void bond_alb_deinitialize(struct bonding *bond)
1248 {
1249         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1250
1251         tlb_deinitialize(bond);
1252
1253         if (bond_info->rlb_enabled) {
1254                 rlb_deinitialize(bond);
1255         }
1256 }
1257
1258 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1259 {
1260         struct bonding *bond = bond_dev->priv;
1261         struct ethhdr *eth_data;
1262         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1263         struct slave *tx_slave = NULL;
1264         static const u32 ip_bcast = 0xffffffff;
1265         int hash_size = 0;
1266         int do_tx_balance = 1;
1267         u32 hash_index = 0;
1268         u8 *hash_start = NULL;
1269         int res = 1;
1270
1271         skb->mac.raw = (unsigned char *)skb->data;
1272         eth_data = eth_hdr(skb);
1273
1274         /* make sure that the curr_active_slave and the slaves list do
1275          * not change during tx
1276          */
1277         read_lock(&bond->lock);
1278         read_lock(&bond->curr_slave_lock);
1279
1280         if (!BOND_IS_OK(bond)) {
1281                 goto out;
1282         }
1283
1284         switch (ntohs(skb->protocol)) {
1285         case ETH_P_IP:
1286                 if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
1287                     (skb->nh.iph->daddr == ip_bcast) ||
1288                     (skb->nh.iph->protocol == IPPROTO_IGMP)) {
1289                         do_tx_balance = 0;
1290                         break;
1291                 }
1292                 hash_start = (char*)&(skb->nh.iph->daddr);
1293                 hash_size = sizeof(skb->nh.iph->daddr);
1294                 break;
1295         case ETH_P_IPV6:
1296                 if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
1297                         do_tx_balance = 0;
1298                         break;
1299                 }
1300
1301                 hash_start = (char*)&(skb->nh.ipv6h->daddr);
1302                 hash_size = sizeof(skb->nh.ipv6h->daddr);
1303                 break;
1304         case ETH_P_IPX:
1305                 if (ipx_hdr(skb)->ipx_checksum !=
1306                     __constant_htons(IPX_NO_CHECKSUM)) {
1307                         /* something is wrong with this packet */
1308                         do_tx_balance = 0;
1309                         break;
1310                 }
1311
1312                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1313                         /* The only protocol worth balancing in
1314                          * this family since it has an "ARP" like
1315                          * mechanism
1316                          */
1317                         do_tx_balance = 0;
1318                         break;
1319                 }
1320
1321                 hash_start = (char*)eth_data->h_dest;
1322                 hash_size = ETH_ALEN;
1323                 break;
1324         case ETH_P_ARP:
1325                 do_tx_balance = 0;
1326                 if (bond_info->rlb_enabled) {
1327                         tx_slave = rlb_arp_xmit(skb, bond);
1328                 }
1329                 break;
1330         default:
1331                 do_tx_balance = 0;
1332                 break;
1333         }
1334
1335         if (do_tx_balance) {
1336                 hash_index = _simple_hash(hash_start, hash_size);
1337                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1338         }
1339
1340         if (!tx_slave) {
1341                 /* unbalanced or unassigned, send through primary */
1342                 tx_slave = bond->curr_active_slave;
1343                 bond_info->unbalanced_load += skb->len;
1344         }
1345
1346         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1347                 if (tx_slave != bond->curr_active_slave) {
1348                         memcpy(eth_data->h_source,
1349                                tx_slave->dev->dev_addr,
1350                                ETH_ALEN);
1351                 }
1352
1353                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1354         } else {
1355                 if (tx_slave) {
1356                         tlb_clear_slave(bond, tx_slave, 0);
1357                 }
1358         }
1359
1360 out:
1361         if (res) {
1362                 /* no suitable interface, frame not sent */
1363                 dev_kfree_skb(skb);
1364         }
1365         read_unlock(&bond->curr_slave_lock);
1366         read_unlock(&bond->lock);
1367         return 0;
1368 }
1369
1370 void bond_alb_monitor(struct bonding *bond)
1371 {
1372         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1373         struct slave *slave;
1374         int i;
1375
1376         read_lock(&bond->lock);
1377
1378         if (bond->kill_timers) {
1379                 goto out;
1380         }
1381
1382         if (bond->slave_cnt == 0) {
1383                 bond_info->tx_rebalance_counter = 0;
1384                 bond_info->lp_counter = 0;
1385                 goto re_arm;
1386         }
1387
1388         bond_info->tx_rebalance_counter++;
1389         bond_info->lp_counter++;
1390
1391         /* send learning packets */
1392         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1393                 /* change of curr_active_slave involves swapping of mac addresses.
1394                  * in order to avoid this swapping from happening while
1395                  * sending the learning packets, the curr_slave_lock must be held for
1396                  * read.
1397                  */
1398                 read_lock(&bond->curr_slave_lock);
1399
1400                 bond_for_each_slave(bond, slave, i) {
1401                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1402                 }
1403
1404                 read_unlock(&bond->curr_slave_lock);
1405
1406                 bond_info->lp_counter = 0;
1407         }
1408
1409         /* rebalance tx traffic */
1410         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1411
1412                 read_lock(&bond->curr_slave_lock);
1413
1414                 bond_for_each_slave(bond, slave, i) {
1415                         tlb_clear_slave(bond, slave, 1);
1416                         if (slave == bond->curr_active_slave) {
1417                                 SLAVE_TLB_INFO(slave).load =
1418                                         bond_info->unbalanced_load /
1419                                                 BOND_TLB_REBALANCE_INTERVAL;
1420                                 bond_info->unbalanced_load = 0;
1421                         }
1422                 }
1423
1424                 read_unlock(&bond->curr_slave_lock);
1425
1426                 bond_info->tx_rebalance_counter = 0;
1427         }
1428
1429         /* handle rlb stuff */
1430         if (bond_info->rlb_enabled) {
1431                 /* the following code changes the promiscuity of the
1432                  * the curr_active_slave. It needs to be locked with a
1433                  * write lock to protect from other code that also
1434                  * sets the promiscuity.
1435                  */
1436                 write_lock_bh(&bond->curr_slave_lock);
1437
1438                 if (bond_info->primary_is_promisc &&
1439                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1440
1441                         bond_info->rlb_promisc_timeout_counter = 0;
1442
1443                         /* If the primary was set to promiscuous mode
1444                          * because a slave was disabled then
1445                          * it can now leave promiscuous mode.
1446                          */
1447                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1448                         bond_info->primary_is_promisc = 0;
1449                 }
1450
1451                 write_unlock_bh(&bond->curr_slave_lock);
1452
1453                 if (bond_info->rlb_rebalance) {
1454                         bond_info->rlb_rebalance = 0;
1455                         rlb_rebalance(bond);
1456                 }
1457
1458                 /* check if clients need updating */
1459                 if (bond_info->rx_ntt) {
1460                         if (bond_info->rlb_update_delay_counter) {
1461                                 --bond_info->rlb_update_delay_counter;
1462                         } else {
1463                                 rlb_update_rx_clients(bond);
1464                                 if (bond_info->rlb_update_retry_counter) {
1465                                         --bond_info->rlb_update_retry_counter;
1466                                 } else {
1467                                         bond_info->rx_ntt = 0;
1468                                 }
1469                         }
1470                 }
1471         }
1472
1473 re_arm:
1474         mod_timer(&(bond_info->alb_timer), jiffies + alb_delta_in_ticks);
1475 out:
1476         read_unlock(&bond->lock);
1477 }
1478
1479 /* assumption: called before the slave is attached to the bond
1480  * and not locked by the bond lock
1481  */
1482 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1483 {
1484         int res;
1485
1486         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1487                                      bond->alb_info.rlb_enabled);
1488         if (res) {
1489                 return res;
1490         }
1491
1492         /* caller must hold the bond lock for write since the mac addresses
1493          * are compared and may be swapped.
1494          */
1495         write_lock_bh(&bond->lock);
1496
1497         res = alb_handle_addr_collision_on_attach(bond, slave);
1498
1499         write_unlock_bh(&bond->lock);
1500
1501         if (res) {
1502                 return res;
1503         }
1504
1505         tlb_init_slave(slave);
1506
1507         /* order a rebalance ASAP */
1508         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1509
1510         if (bond->alb_info.rlb_enabled) {
1511                 bond->alb_info.rlb_rebalance = 1;
1512         }
1513
1514         return 0;
1515 }
1516
1517 /* Caller must hold bond lock for write */
1518 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1519 {
1520         if (bond->slave_cnt > 1) {
1521                 alb_change_hw_addr_on_detach(bond, slave);
1522         }
1523
1524         tlb_clear_slave(bond, slave, 0);
1525
1526         if (bond->alb_info.rlb_enabled) {
1527                 bond->alb_info.next_rx_slave = NULL;
1528                 rlb_clear_slave(bond, slave);
1529         }
1530 }
1531
1532 /* Caller must hold bond lock for read */
1533 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1534 {
1535         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1536
1537         if (link == BOND_LINK_DOWN) {
1538                 tlb_clear_slave(bond, slave, 0);
1539                 if (bond->alb_info.rlb_enabled) {
1540                         rlb_clear_slave(bond, slave);
1541                 }
1542         } else if (link == BOND_LINK_UP) {
1543                 /* order a rebalance ASAP */
1544                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1545                 if (bond->alb_info.rlb_enabled) {
1546                         bond->alb_info.rlb_rebalance = 1;
1547                         /* If the updelay module parameter is smaller than the
1548                          * forwarding delay of the switch the rebalance will
1549                          * not work because the rebalance arp replies will
1550                          * not be forwarded to the clients..
1551                          */
1552                 }
1553         }
1554 }
1555
1556 /**
1557  * bond_alb_handle_active_change - assign new curr_active_slave
1558  * @bond: our bonding struct
1559  * @new_slave: new slave to assign
1560  *
1561  * Set the bond->curr_active_slave to @new_slave and handle
1562  * mac address swapping and promiscuity changes as needed.
1563  *
1564  * Caller must hold bond curr_slave_lock for write (or bond lock for write)
1565  */
1566 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1567 {
1568         struct slave *swap_slave;
1569         int i;
1570
1571         if (bond->curr_active_slave == new_slave) {
1572                 return;
1573         }
1574
1575         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1576                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1577                 bond->alb_info.primary_is_promisc = 0;
1578                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1579         }
1580
1581         swap_slave = bond->curr_active_slave;
1582         bond->curr_active_slave = new_slave;
1583
1584         if (!new_slave || (bond->slave_cnt == 0)) {
1585                 return;
1586         }
1587
1588         /* set the new curr_active_slave to the bonds mac address
1589          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1590          */
1591         if (!swap_slave) {
1592                 struct slave *tmp_slave;
1593                 /* find slave that is holding the bond's mac address */
1594                 bond_for_each_slave(bond, tmp_slave, i) {
1595                         if (!memcmp(tmp_slave->dev->dev_addr,
1596                                     bond->dev->dev_addr, ETH_ALEN)) {
1597                                 swap_slave = tmp_slave;
1598                                 break;
1599                         }
1600                 }
1601         }
1602
1603         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1604         if (swap_slave) {
1605                 /* swap mac address */
1606                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1607         } else {
1608                 /* set the new_slave to the bond mac address */
1609                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1610                                        bond->alb_info.rlb_enabled);
1611                 /* fasten bond mac on new current slave */
1612                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1613         }
1614 }
1615
1616 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1617 {
1618         struct bonding *bond = bond_dev->priv;
1619         struct sockaddr *sa = addr;
1620         struct slave *slave, *swap_slave;
1621         int res;
1622         int i;
1623
1624         if (!is_valid_ether_addr(sa->sa_data)) {
1625                 return -EADDRNOTAVAIL;
1626         }
1627
1628         res = alb_set_mac_address(bond, addr);
1629         if (res) {
1630                 return res;
1631         }
1632
1633         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1634
1635         /* If there is no curr_active_slave there is nothing else to do.
1636          * Otherwise we'll need to pass the new address to it and handle
1637          * duplications.
1638          */
1639         if (!bond->curr_active_slave) {
1640                 return 0;
1641         }
1642
1643         swap_slave = NULL;
1644
1645         bond_for_each_slave(bond, slave, i) {
1646                 if (!memcmp(slave->dev->dev_addr, bond_dev->dev_addr, ETH_ALEN)) {
1647                         swap_slave = slave;
1648                         break;
1649                 }
1650         }
1651
1652         if (swap_slave) {
1653                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1654         } else {
1655                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1656                                        bond->alb_info.rlb_enabled);
1657
1658                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1659                 if (bond->alb_info.rlb_enabled) {
1660                         /* inform clients mac address has changed */
1661                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1662                 }
1663         }
1664
1665         return 0;
1666 }
1667
1668 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1669 {
1670         if (bond->alb_info.current_alb_vlan &&
1671             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1672                 bond->alb_info.current_alb_vlan = NULL;
1673         }
1674
1675         if (bond->alb_info.rlb_enabled) {
1676                 rlb_clear_vlan(bond, vlan_id);
1677         }
1678 }
1679