drivers/net/bonding/bond_alb.c

   1 /*
   2  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License as published by the
   6  * Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  */
  22
  23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  24
  25 #include <linux/skbuff.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/pkt_sched.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/slab.h>
  31 #include <linux/timer.h>
  32 #include <linux/ip.h>
  33 #include <linux/ipv6.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/if_ether.h>
  36 #include <linux/if_bonding.h>
  37 #include <linux/if_vlan.h>
  38 #include <linux/in.h>
  39 #include <net/ipx.h>
  40 #include <net/arp.h>
  41 #include <net/ipv6.h>
  42 #include <asm/byteorder.h>
  43 #include "bonding.h"
  44 #include "bond_alb.h"
  45
  46
  47
  48 #ifndef __long_aligned
  49 #define __long_aligned __attribute__((aligned((sizeof(long)))))
  50 #endif
  51 static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
  52         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  53 };
  54 static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
  55         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  56 };
  57 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  58
  59 #pragma pack(1)
  60 struct learning_pkt {
  61         u8 mac_dst[ETH_ALEN];
  62         u8 mac_src[ETH_ALEN];
  63         __be16 type;
  64         u8 padding[ETH_ZLEN - ETH_HLEN];
  65 };
  66
  67 struct arp_pkt {
  68         __be16  hw_addr_space;
  69         __be16  prot_addr_space;
  70         u8      hw_addr_len;
  71         u8      prot_addr_len;
  72         __be16  op_code;
  73         u8      mac_src[ETH_ALEN];      /* sender hardware address */
  74         __be32  ip_src;                 /* sender IP address */
  75         u8      mac_dst[ETH_ALEN];      /* target hardware address */
  76         __be32  ip_dst;                 /* target IP address */
  77 };
  78 #pragma pack()
  79
  80 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
  81 {
  82         return (struct arp_pkt *)skb_network_header(skb);
  83 }
  84
  85 /* Forward declaration */
  86 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
  87
  88 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  89 {
  90         int i;
  91         u8 hash = 0;
  92
  93         for (i = 0; i < hash_size; i++) {
  94                 hash ^= hash_start[i];
  95         }
  96
  97         return hash;
  98 }
  99
 100 /*********************** tlb specific functions ***************************/
 101
 102 static inline void _lock_tx_hashtbl_bh(struct bonding *bond)
 103 {
 104         spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 105 }
 106
 107 static inline void _unlock_tx_hashtbl_bh(struct bonding *bond)
 108 {
 109         spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 110 }
 111
 112 static inline void _lock_tx_hashtbl(struct bonding *bond)
 113 {
 114         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 115 }
 116
 117 static inline void _unlock_tx_hashtbl(struct bonding *bond)
 118 {
 119         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 120 }
 121
 122 /* Caller must hold tx_hashtbl lock */
 123 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 124 {
 125         if (save_load) {
 126                 entry->load_history = 1 + entry->tx_bytes /
 127                                       BOND_TLB_REBALANCE_INTERVAL;
 128                 entry->tx_bytes = 0;
 129         }
 130
 131         entry->tx_slave = NULL;
 132         entry->next = TLB_NULL_INDEX;
 133         entry->prev = TLB_NULL_INDEX;
 134 }
 135
 136 static inline void tlb_init_slave(struct slave *slave)
 137 {
 138         SLAVE_TLB_INFO(slave).load = 0;
 139         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 140 }
 141
 142 /* Caller must hold bond lock for read, BH disabled */
 143 static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
 144                          int save_load)
 145 {
 146         struct tlb_client_info *tx_hash_table;
 147         u32 index;
 148
 149         /* clear slave from tx_hashtbl */
 150         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 151
 152         /* skip this if we've already freed the tx hash table */
 153         if (tx_hash_table) {
 154                 index = SLAVE_TLB_INFO(slave).head;
 155                 while (index != TLB_NULL_INDEX) {
 156                         u32 next_index = tx_hash_table[index].next;
 157                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 158                         index = next_index;
 159                 }
 160         }
 161
 162         tlb_init_slave(slave);
 163 }
 164
 165 /* Caller must hold bond lock for read */
 166 static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 167                          int save_load)
 168 {
 169         _lock_tx_hashtbl_bh(bond);
 170         __tlb_clear_slave(bond, slave, save_load);
 171         _unlock_tx_hashtbl_bh(bond);
 172 }
 173
 174 /* Must be called before starting the monitor timer */
 175 static int tlb_initialize(struct bonding *bond)
 176 {
 177         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 178         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 179         struct tlb_client_info *new_hashtbl;
 180         int i;
 181
 182         new_hashtbl = kzalloc(size, GFP_KERNEL);
 183         if (!new_hashtbl)
 184                 return -1;
 185
 186         _lock_tx_hashtbl_bh(bond);
 187
 188         bond_info->tx_hashtbl = new_hashtbl;
 189
 190         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
 191                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 192         }
 193
 194         _unlock_tx_hashtbl_bh(bond);
 195
 196         return 0;
 197 }
 198
 199 /* Must be called only after all slaves have been released */
 200 static void tlb_deinitialize(struct bonding *bond)
 201 {
 202         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 203
 204         _lock_tx_hashtbl_bh(bond);
 205
 206         kfree(bond_info->tx_hashtbl);
 207         bond_info->tx_hashtbl = NULL;
 208
 209         _unlock_tx_hashtbl_bh(bond);
 210 }
 211
 212 static long long compute_gap(struct slave *slave)
 213 {
 214         return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 215                (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 216 }
 217
 218 /* Caller must hold bond lock for read */
 219 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 220 {
 221         struct slave *slave, *least_loaded;
 222         long long max_gap;
 223         int i;
 224
 225         least_loaded = NULL;
 226         max_gap = LLONG_MIN;
 227
 228         /* Find the slave with the largest gap */
 229         bond_for_each_slave(bond, slave, i) {
 230                 if (SLAVE_IS_OK(slave)) {
 231                         long long gap = compute_gap(slave);
 232
 233                         if (max_gap < gap) {
 234                                 least_loaded = slave;
 235                                 max_gap = gap;
 236                         }
 237                 }
 238         }
 239
 240         return least_loaded;
 241 }
 242
 243 static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 244                                                 u32 skb_len)
 245 {
 246         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 247         struct tlb_client_info *hash_table;
 248         struct slave *assigned_slave;
 249
 250         hash_table = bond_info->tx_hashtbl;
 251         assigned_slave = hash_table[hash_index].tx_slave;
 252         if (!assigned_slave) {
 253                 assigned_slave = tlb_get_least_loaded_slave(bond);
 254
 255                 if (assigned_slave) {
 256                         struct tlb_slave_info *slave_info =
 257                                 &(SLAVE_TLB_INFO(assigned_slave));
 258                         u32 next_index = slave_info->head;
 259
 260                         hash_table[hash_index].tx_slave = assigned_slave;
 261                         hash_table[hash_index].next = next_index;
 262                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 263
 264                         if (next_index != TLB_NULL_INDEX) {
 265                                 hash_table[next_index].prev = hash_index;
 266                         }
 267
 268                         slave_info->head = hash_index;
 269                         slave_info->load +=
 270                                 hash_table[hash_index].load_history;
 271                 }
 272         }
 273
 274         if (assigned_slave) {
 275                 hash_table[hash_index].tx_bytes += skb_len;
 276         }
 277
 278         return assigned_slave;
 279 }
 280
 281 /* Caller must hold bond lock for read */
 282 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 283                                         u32 skb_len)
 284 {
 285         struct slave *tx_slave;
 286         /*
 287          * We don't need to disable softirq here, becase
 288          * tlb_choose_channel() is only called by bond_alb_xmit()
 289          * which already has softirq disabled.
 290          */
 291         _lock_tx_hashtbl(bond);
 292         tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 293         _unlock_tx_hashtbl(bond);
 294         return tx_slave;
 295 }
 296
 297 /*********************** rlb specific functions ***************************/
 298 static inline void _lock_rx_hashtbl_bh(struct bonding *bond)
 299 {
 300         spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 301 }
 302
 303 static inline void _unlock_rx_hashtbl_bh(struct bonding *bond)
 304 {
 305         spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 306 }
 307
 308 static inline void _lock_rx_hashtbl(struct bonding *bond)
 309 {
 310         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 311 }
 312
 313 static inline void _unlock_rx_hashtbl(struct bonding *bond)
 314 {
 315         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 316 }
 317
 318 /* when an ARP REPLY is received from a client update its info
 319  * in the rx_hashtbl
 320  */
 321 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 322 {
 323         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 324         struct rlb_client_info *client_info;
 325         u32 hash_index;
 326
 327         _lock_rx_hashtbl_bh(bond);
 328
 329         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
 330         client_info = &(bond_info->rx_hashtbl[hash_index]);
 331
 332         if ((client_info->assigned) &&
 333             (client_info->ip_src == arp->ip_dst) &&
 334             (client_info->ip_dst == arp->ip_src) &&
 335             (compare_ether_addr_64bits(client_info->mac_dst, arp->mac_src))) {
 336                 /* update the clients MAC address */
 337                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
 338                 client_info->ntt = 1;
 339                 bond_info->rx_ntt = 1;
 340         }
 341
 342         _unlock_rx_hashtbl_bh(bond);
 343 }
 344
 345 static void rlb_arp_recv(struct sk_buff *skb, struct bonding *bond,
 346                          struct slave *slave)
 347 {
 348         struct arp_pkt *arp;
 349
 350         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 351                 return;
 352
 353         arp = (struct arp_pkt *) skb->data;
 354         if (!arp) {
 355                 pr_debug("Packet has no ARP data\n");
 356                 return;
 357         }
 358
 359         if (!pskb_may_pull(skb, arp_hdr_len(bond->dev)))
 360                 return;
 361
 362         if (skb->len < sizeof(struct arp_pkt)) {
 363                 pr_debug("Packet is too small to be an ARP\n");
 364                 return;
 365         }
 366
 367         if (arp->op_code == htons(ARPOP_REPLY)) {
 368                 /* update rx hash table for this ARP */
 369                 rlb_update_entry_from_arp(bond, arp);
 370                 pr_debug("Server received an ARP Reply from client\n");
 371         }
 372 }
 373
 374 /* Caller must hold bond lock for read */
 375 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 376 {
 377         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 378         struct slave *rx_slave, *slave, *start_at;
 379         int i = 0;
 380
 381         if (bond_info->next_rx_slave) {
 382                 start_at = bond_info->next_rx_slave;
 383         } else {
 384                 start_at = bond->first_slave;
 385         }
 386
 387         rx_slave = NULL;
 388
 389         bond_for_each_slave_from(bond, slave, i, start_at) {
 390                 if (SLAVE_IS_OK(slave)) {
 391                         if (!rx_slave) {
 392                                 rx_slave = slave;
 393                         } else if (slave->speed > rx_slave->speed) {
 394                                 rx_slave = slave;
 395                         }
 396                 }
 397         }
 398
 399         if (rx_slave) {
 400                 bond_info->next_rx_slave = rx_slave->next;
 401         }
 402
 403         return rx_slave;
 404 }
 405
 406 /* teach the switch the mac of a disabled slave
 407  * on the primary for fault tolerance
 408  *
 409  * Caller must hold bond->curr_slave_lock for write or bond lock for write
 410  */
 411 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 412 {
 413         if (!bond->curr_active_slave) {
 414                 return;
 415         }
 416
 417         if (!bond->alb_info.primary_is_promisc) {
 418                 if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
 419                         bond->alb_info.primary_is_promisc = 1;
 420                 else
 421                         bond->alb_info.primary_is_promisc = 0;
 422         }
 423
 424         bond->alb_info.rlb_promisc_timeout_counter = 0;
 425
 426         alb_send_learning_packets(bond->curr_active_slave, addr);
 427 }
 428
 429 /* slave being removed should not be active at this point
 430  *
 431  * Caller must hold bond lock for read
 432  */
 433 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 434 {
 435         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 436         struct rlb_client_info *rx_hash_table;
 437         u32 index, next_index;
 438
 439         /* clear slave from rx_hashtbl */
 440         _lock_rx_hashtbl_bh(bond);
 441
 442         rx_hash_table = bond_info->rx_hashtbl;
 443         index = bond_info->rx_hashtbl_head;
 444         for (; index != RLB_NULL_INDEX; index = next_index) {
 445                 next_index = rx_hash_table[index].next;
 446                 if (rx_hash_table[index].slave == slave) {
 447                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 448
 449                         if (assigned_slave) {
 450                                 rx_hash_table[index].slave = assigned_slave;
 451                                 if (compare_ether_addr_64bits(rx_hash_table[index].mac_dst,
 452                                                               mac_bcast)) {
 453                                         bond_info->rx_hashtbl[index].ntt = 1;
 454                                         bond_info->rx_ntt = 1;
 455                                         /* A slave has been removed from the
 456                                          * table because it is either disabled
 457                                          * or being released. We must retry the
 458                                          * update to avoid clients from not
 459                                          * being updated & disconnecting when
 460                                          * there is stress
 461                                          */
 462                                         bond_info->rlb_update_retry_counter =
 463                                                 RLB_UPDATE_RETRY;
 464                                 }
 465                         } else {  /* there is no active slave */
 466                                 rx_hash_table[index].slave = NULL;
 467                         }
 468                 }
 469         }
 470
 471         _unlock_rx_hashtbl_bh(bond);
 472
 473         write_lock_bh(&bond->curr_slave_lock);
 474
 475         if (slave != bond->curr_active_slave) {
 476                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 477         }
 478
 479         write_unlock_bh(&bond->curr_slave_lock);
 480 }
 481
 482 static void rlb_update_client(struct rlb_client_info *client_info)
 483 {
 484         int i;
 485
 486         if (!client_info->slave) {
 487                 return;
 488         }
 489
 490         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 491                 struct sk_buff *skb;
 492
 493                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 494                                  client_info->ip_dst,
 495                                  client_info->slave->dev,
 496                                  client_info->ip_src,
 497                                  client_info->mac_dst,
 498                                  client_info->slave->dev->dev_addr,
 499                                  client_info->mac_dst);
 500                 if (!skb) {
 501                         pr_err("%s: Error: failed to create an ARP packet\n",
 502                                client_info->slave->dev->master->name);
 503                         continue;
 504                 }
 505
 506                 skb->dev = client_info->slave->dev;
 507
 508                 if (client_info->tag) {
 509                         skb = vlan_put_tag(skb, client_info->vlan_id);
 510                         if (!skb) {
 511                                 pr_err("%s: Error: failed to insert VLAN tag\n",
 512                                        client_info->slave->dev->master->name);
 513                                 continue;
 514                         }
 515                 }
 516
 517                 arp_xmit(skb);
 518         }
 519 }
 520
 521 /* sends ARP REPLIES that update the clients that need updating */
 522 static void rlb_update_rx_clients(struct bonding *bond)
 523 {
 524         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 525         struct rlb_client_info *client_info;
 526         u32 hash_index;
 527
 528         _lock_rx_hashtbl_bh(bond);
 529
 530         hash_index = bond_info->rx_hashtbl_head;
 531         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 532                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 533                 if (client_info->ntt) {
 534                         rlb_update_client(client_info);
 535                         if (bond_info->rlb_update_retry_counter == 0) {
 536                                 client_info->ntt = 0;
 537                         }
 538                 }
 539         }
 540
 541         /* do not update the entries again until this counter is zero so that
 542          * not to confuse the clients.
 543          */
 544         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 545
 546         _unlock_rx_hashtbl_bh(bond);
 547 }
 548
 549 /* The slave was assigned a new mac address - update the clients */
 550 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 551 {
 552         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 553         struct rlb_client_info *client_info;
 554         int ntt = 0;
 555         u32 hash_index;
 556
 557         _lock_rx_hashtbl_bh(bond);
 558
 559         hash_index = bond_info->rx_hashtbl_head;
 560         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 561                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 562
 563                 if ((client_info->slave == slave) &&
 564                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 565                         client_info->ntt = 1;
 566                         ntt = 1;
 567                 }
 568         }
 569
 570         // update the team's flag only after the whole iteration
 571         if (ntt) {
 572                 bond_info->rx_ntt = 1;
 573                 //fasten the change
 574                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 575         }
 576
 577         _unlock_rx_hashtbl_bh(bond);
 578 }
 579
 580 /* mark all clients using src_ip to be updated */
 581 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 582 {
 583         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 584         struct rlb_client_info *client_info;
 585         u32 hash_index;
 586
 587         _lock_rx_hashtbl(bond);
 588
 589         hash_index = bond_info->rx_hashtbl_head;
 590         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 591                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 592
 593                 if (!client_info->slave) {
 594                         pr_err("%s: Error: found a client with no channel in 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                     compare_ether_addr_64bits(client_info->slave->dev->dev_addr,
 604                            bond->dev->dev_addr) &&
 605                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 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 = arp_pkt(skb);
 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_dst));
 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 (compare_ether_addr_64bits(arp->mac_dst, mac_bcast)) {
 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 (compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
 668                         client_info->ntt = 1;
 669                         bond->alb_info.rx_ntt = 1;
 670                 } else {
 671                         client_info->ntt = 0;
 672                 }
 673
 674                 if (bond_vlan_used(bond)) {
 675                         if (!vlan_get_tag(skb, &client_info->vlan_id))
 676                                 client_info->tag = 1;
 677                 }
 678
 679                 if (!client_info->assigned) {
 680                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
 681                         bond_info->rx_hashtbl_head = hash_index;
 682                         client_info->next = prev_tbl_head;
 683                         if (prev_tbl_head != RLB_NULL_INDEX) {
 684                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
 685                                         hash_index;
 686                         }
 687                         client_info->assigned = 1;
 688                 }
 689         }
 690
 691         _unlock_rx_hashtbl(bond);
 692
 693         return assigned_slave;
 694 }
 695
 696 /* chooses (and returns) transmit channel for arp reply
 697  * does not choose channel for other arp types since they are
 698  * sent on the curr_active_slave
 699  */
 700 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 701 {
 702         struct arp_pkt *arp = arp_pkt(skb);
 703         struct slave *tx_slave = NULL;
 704
 705         if (arp->op_code == htons(ARPOP_REPLY)) {
 706                 /* the arp must be sent on the selected
 707                 * rx channel
 708                 */
 709                 tx_slave = rlb_choose_channel(skb, bond);
 710                 if (tx_slave) {
 711                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
 712                 }
 713                 pr_debug("Server sent ARP Reply packet\n");
 714         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 715                 /* Create an entry in the rx_hashtbl for this client as a
 716                  * place holder.
 717                  * When the arp reply is received the entry will be updated
 718                  * with the correct unicast address of the client.
 719                  */
 720                 rlb_choose_channel(skb, bond);
 721
 722                 /* The ARP reply packets must be delayed so that
 723                  * they can cancel out the influence of the ARP request.
 724                  */
 725                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 726
 727                 /* arp requests are broadcast and are sent on the primary
 728                  * the arp request will collapse all clients on the subnet to
 729                  * the primary slave. We must register these clients to be
 730                  * updated with their assigned mac.
 731                  */
 732                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 733                 pr_debug("Server sent ARP Request packet\n");
 734         }
 735
 736         return tx_slave;
 737 }
 738
 739 /* Caller must hold bond lock for read */
 740 static void rlb_rebalance(struct bonding *bond)
 741 {
 742         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 743         struct slave *assigned_slave;
 744         struct rlb_client_info *client_info;
 745         int ntt;
 746         u32 hash_index;
 747
 748         _lock_rx_hashtbl_bh(bond);
 749
 750         ntt = 0;
 751         hash_index = bond_info->rx_hashtbl_head;
 752         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
 753                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 754                 assigned_slave = rlb_next_rx_slave(bond);
 755                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 756                         client_info->slave = assigned_slave;
 757                         client_info->ntt = 1;
 758                         ntt = 1;
 759                 }
 760         }
 761
 762         /* update the team's flag only after the whole iteration */
 763         if (ntt) {
 764                 bond_info->rx_ntt = 1;
 765         }
 766         _unlock_rx_hashtbl_bh(bond);
 767 }
 768
 769 /* Caller must hold rx_hashtbl lock */
 770 static void rlb_init_table_entry(struct rlb_client_info *entry)
 771 {
 772         memset(entry, 0, sizeof(struct rlb_client_info));
 773         entry->next = RLB_NULL_INDEX;
 774         entry->prev = RLB_NULL_INDEX;
 775 }
 776
 777 static int rlb_initialize(struct bonding *bond)
 778 {
 779         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 780         struct rlb_client_info  *new_hashtbl;
 781         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 782         int i;
 783
 784         new_hashtbl = kmalloc(size, GFP_KERNEL);
 785         if (!new_hashtbl)
 786                 return -1;
 787
 788         _lock_rx_hashtbl_bh(bond);
 789
 790         bond_info->rx_hashtbl = new_hashtbl;
 791
 792         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 793
 794         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
 795                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 796         }
 797
 798         _unlock_rx_hashtbl_bh(bond);
 799
 800         /* register to receive ARPs */
 801         bond->recv_probe = rlb_arp_recv;
 802
 803         return 0;
 804 }
 805
 806 static void rlb_deinitialize(struct bonding *bond)
 807 {
 808         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 809
 810         _lock_rx_hashtbl_bh(bond);
 811
 812         kfree(bond_info->rx_hashtbl);
 813         bond_info->rx_hashtbl = NULL;
 814         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
 815
 816         _unlock_rx_hashtbl_bh(bond);
 817 }
 818
 819 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 820 {
 821         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 822         u32 curr_index;
 823
 824         _lock_rx_hashtbl_bh(bond);
 825
 826         curr_index = bond_info->rx_hashtbl_head;
 827         while (curr_index != RLB_NULL_INDEX) {
 828                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 829                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
 830                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
 831
 832                 if (curr->tag && (curr->vlan_id == vlan_id)) {
 833                         if (curr_index == bond_info->rx_hashtbl_head) {
 834                                 bond_info->rx_hashtbl_head = next_index;
 835                         }
 836                         if (prev_index != RLB_NULL_INDEX) {
 837                                 bond_info->rx_hashtbl[prev_index].next = next_index;
 838                         }
 839                         if (next_index != RLB_NULL_INDEX) {
 840                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
 841                         }
 842
 843                         rlb_init_table_entry(curr);
 844                 }
 845
 846                 curr_index = next_index;
 847         }
 848
 849         _unlock_rx_hashtbl_bh(bond);
 850 }
 851
 852 /*********************** tlb/rlb shared functions *********************/
 853
 854 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
 855 {
 856         struct bonding *bond = bond_get_bond_by_slave(slave);
 857         struct learning_pkt pkt;
 858         int size = sizeof(struct learning_pkt);
 859         int i;
 860
 861         memset(&pkt, 0, size);
 862         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
 863         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
 864         pkt.type = cpu_to_be16(ETH_P_LOOP);
 865
 866         for (i = 0; i < MAX_LP_BURST; i++) {
 867                 struct sk_buff *skb;
 868                 char *data;
 869
 870                 skb = dev_alloc_skb(size);
 871                 if (!skb) {
 872                         return;
 873                 }
 874
 875                 data = skb_put(skb, size);
 876                 memcpy(data, &pkt, size);
 877
 878                 skb_reset_mac_header(skb);
 879                 skb->network_header = skb->mac_header + ETH_HLEN;
 880                 skb->protocol = pkt.type;
 881                 skb->priority = TC_PRIO_CONTROL;
 882                 skb->dev = slave->dev;
 883
 884                 if (bond_vlan_used(bond)) {
 885                         struct vlan_entry *vlan;
 886
 887                         vlan = bond_next_vlan(bond,
 888                                               bond->alb_info.current_alb_vlan);
 889
 890                         bond->alb_info.current_alb_vlan = vlan;
 891                         if (!vlan) {
 892                                 kfree_skb(skb);
 893                                 continue;
 894                         }
 895
 896                         skb = vlan_put_tag(skb, vlan->vlan_id);
 897                         if (!skb) {
 898                                 pr_err("%s: Error: failed to insert VLAN tag\n",
 899                                        bond->dev->name);
 900                                 continue;
 901                         }
 902                 }
 903
 904                 dev_queue_xmit(skb);
 905         }
 906 }
 907
 908 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
 909 {
 910         struct net_device *dev = slave->dev;
 911         struct sockaddr s_addr;
 912
 913         if (slave->bond->params.mode == BOND_MODE_TLB) {
 914                 memcpy(dev->dev_addr, addr, dev->addr_len);
 915                 return 0;
 916         }
 917
 918         /* for rlb each slave must have a unique hw mac addresses so that */
 919         /* each slave will receive packets destined to a different mac */
 920         memcpy(s_addr.sa_data, addr, dev->addr_len);
 921         s_addr.sa_family = dev->type;
 922         if (dev_set_mac_address(dev, &s_addr)) {
 923                 pr_err("%s: Error: dev_set_mac_address of dev %s failed!\n"
 924                        "ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
 925                        dev->master->name, dev->name);
 926                 return -EOPNOTSUPP;
 927         }
 928         return 0;
 929 }
 930
 931 /*
 932  * Swap MAC addresses between two slaves.
 933  *
 934  * Called with RTNL held, and no other locks.
 935  *
 936  */
 937
 938 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
 939 {
 940         u8 tmp_mac_addr[ETH_ALEN];
 941
 942         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
 943         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
 944         alb_set_slave_mac_addr(slave2, tmp_mac_addr);
 945
 946 }
 947
 948 /*
 949  * Send learning packets after MAC address swap.
 950  *
 951  * Called with RTNL and no other locks
 952  */
 953 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
 954                                 struct slave *slave2)
 955 {
 956         int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
 957         struct slave *disabled_slave = NULL;
 958
 959         ASSERT_RTNL();
 960
 961         /* fasten the change in the switch */
 962         if (SLAVE_IS_OK(slave1)) {
 963                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
 964                 if (bond->alb_info.rlb_enabled) {
 965                         /* inform the clients that the mac address
 966                          * has changed
 967                          */
 968                         rlb_req_update_slave_clients(bond, slave1);
 969                 }
 970         } else {
 971                 disabled_slave = slave1;
 972         }
 973
 974         if (SLAVE_IS_OK(slave2)) {
 975                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
 976                 if (bond->alb_info.rlb_enabled) {
 977                         /* inform the clients that the mac address
 978                          * has changed
 979                          */
 980                         rlb_req_update_slave_clients(bond, slave2);
 981                 }
 982         } else {
 983                 disabled_slave = slave2;
 984         }
 985
 986         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
 987                 /* A disabled slave was assigned an active mac addr */
 988                 rlb_teach_disabled_mac_on_primary(bond,
 989                                                   disabled_slave->dev->dev_addr);
 990         }
 991 }
 992
 993 /**
 994  * alb_change_hw_addr_on_detach
 995  * @bond: bonding we're working on
 996  * @slave: the slave that was just detached
 997  *
 998  * We assume that @slave was already detached from the slave list.
 999  *
1000  * If @slave's permanent hw address is different both from its current
1001  * address and from @bond's address, then somewhere in the bond there's
1002  * a slave that has @slave's permanet address as its current address.
1003  * We'll make sure that that slave no longer uses @slave's permanent address.
1004  *
1005  * Caller must hold RTNL and no other locks
1006  */
1007 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1008 {
1009         int perm_curr_diff;
1010         int perm_bond_diff;
1011
1012         perm_curr_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1013                                                    slave->dev->dev_addr);
1014         perm_bond_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1015                                                    bond->dev->dev_addr);
1016
1017         if (perm_curr_diff && perm_bond_diff) {
1018                 struct slave *tmp_slave;
1019                 int i, found = 0;
1020
1021                 bond_for_each_slave(bond, tmp_slave, i) {
1022                         if (!compare_ether_addr_64bits(slave->perm_hwaddr,
1023                                                        tmp_slave->dev->dev_addr)) {
1024                                 found = 1;
1025                                 break;
1026                         }
1027                 }
1028
1029                 if (found) {
1030                         /* locking: needs RTNL and nothing else */
1031                         alb_swap_mac_addr(bond, slave, tmp_slave);
1032                         alb_fasten_mac_swap(bond, slave, tmp_slave);
1033                 }
1034         }
1035 }
1036
1037 /**
1038  * alb_handle_addr_collision_on_attach
1039  * @bond: bonding we're working on
1040  * @slave: the slave that was just attached
1041  *
1042  * checks uniqueness of slave's mac address and handles the case the
1043  * new slave uses the bonds mac address.
1044  *
1045  * If the permanent hw address of @slave is @bond's hw address, we need to
1046  * find a different hw address to give @slave, that isn't in use by any other
1047  * slave in the bond. This address must be, of course, one of the permanent
1048  * addresses of the other slaves.
1049  *
1050  * We go over the slave list, and for each slave there we compare its
1051  * permanent hw address with the current address of all the other slaves.
1052  * If no match was found, then we've found a slave with a permanent address
1053  * that isn't used by any other slave in the bond, so we can assign it to
1054  * @slave.
1055  *
1056  * assumption: this function is called before @slave is attached to the
1057  *             bond slave list.
1058  *
1059  * caller must hold the bond lock for write since the mac addresses are compared
1060  * and may be swapped.
1061  */
1062 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1063 {
1064         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1065         struct slave *has_bond_addr = bond->curr_active_slave;
1066         int i, j, found = 0;
1067
1068         if (bond->slave_cnt == 0) {
1069                 /* this is the first slave */
1070                 return 0;
1071         }
1072
1073         /* if slave's mac address differs from bond's mac address
1074          * check uniqueness of slave's mac address against the other
1075          * slaves in the bond.
1076          */
1077         if (compare_ether_addr_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1078                 bond_for_each_slave(bond, tmp_slave1, i) {
1079                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1080                                                        slave->dev->dev_addr)) {
1081                                 found = 1;
1082                                 break;
1083                         }
1084                 }
1085
1086                 if (!found)
1087                         return 0;
1088
1089                 /* Try setting slave mac to bond address and fall-through
1090                    to code handling that situation below... */
1091                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1092         }
1093
1094         /* The slave's address is equal to the address of the bond.
1095          * Search for a spare address in the bond for this slave.
1096          */
1097         free_mac_slave = NULL;
1098
1099         bond_for_each_slave(bond, tmp_slave1, i) {
1100                 found = 0;
1101                 bond_for_each_slave(bond, tmp_slave2, j) {
1102                         if (!compare_ether_addr_64bits(tmp_slave1->perm_hwaddr,
1103                                                        tmp_slave2->dev->dev_addr)) {
1104                                 found = 1;
1105                                 break;
1106                         }
1107                 }
1108
1109                 if (!found) {
1110                         /* no slave has tmp_slave1's perm addr
1111                          * as its curr addr
1112                          */
1113                         free_mac_slave = tmp_slave1;
1114                         break;
1115                 }
1116
1117                 if (!has_bond_addr) {
1118                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1119                                                        bond->dev->dev_addr)) {
1120
1121                                 has_bond_addr = tmp_slave1;
1122                         }
1123                 }
1124         }
1125
1126         if (free_mac_slave) {
1127                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1128
1129                 pr_warning("%s: Warning: the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1130                            bond->dev->name, slave->dev->name,
1131                            free_mac_slave->dev->name);
1132
1133         } else if (has_bond_addr) {
1134                 pr_err("%s: Error: the hw address of slave %s is in use by the bond; couldn't find a slave with a free hw address to give it (this should not have happened)\n",
1135                        bond->dev->name, slave->dev->name);
1136                 return -EFAULT;
1137         }
1138
1139         return 0;
1140 }
1141
1142 /**
1143  * alb_set_mac_address
1144  * @bond:
1145  * @addr:
1146  *
1147  * In TLB mode all slaves are configured to the bond's hw address, but set
1148  * their dev_addr field to different addresses (based on their permanent hw
1149  * addresses).
1150  *
1151  * For each slave, this function sets the interface to the new address and then
1152  * changes its dev_addr field to its previous value.
1153  *
1154  * Unwinding assumes bond's mac address has not yet changed.
1155  */
1156 static int alb_set_mac_address(struct bonding *bond, void *addr)
1157 {
1158         struct sockaddr sa;
1159         struct slave *slave, *stop_at;
1160         char tmp_addr[ETH_ALEN];
1161         int res;
1162         int i;
1163
1164         if (bond->alb_info.rlb_enabled) {
1165                 return 0;
1166         }
1167
1168         bond_for_each_slave(bond, slave, i) {
1169                 /* save net_device's current hw address */
1170                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1171
1172                 res = dev_set_mac_address(slave->dev, addr);
1173
1174                 /* restore net_device's hw address */
1175                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1176
1177                 if (res)
1178                         goto unwind;
1179         }
1180
1181         return 0;
1182
1183 unwind:
1184         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1185         sa.sa_family = bond->dev->type;
1186
1187         /* unwind from head to the slave that failed */
1188         stop_at = slave;
1189         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1190                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1191                 dev_set_mac_address(slave->dev, &sa);
1192                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1193         }
1194
1195         return res;
1196 }
1197
1198 /************************ exported alb funcions ************************/
1199
1200 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1201 {
1202         int res;
1203
1204         res = tlb_initialize(bond);
1205         if (res) {
1206                 return res;
1207         }
1208
1209         if (rlb_enabled) {
1210                 bond->alb_info.rlb_enabled = 1;
1211                 /* initialize rlb */
1212                 res = rlb_initialize(bond);
1213                 if (res) {
1214                         tlb_deinitialize(bond);
1215                         return res;
1216                 }
1217         } else {
1218                 bond->alb_info.rlb_enabled = 0;
1219         }
1220
1221         return 0;
1222 }
1223
1224 void bond_alb_deinitialize(struct bonding *bond)
1225 {
1226         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1227
1228         tlb_deinitialize(bond);
1229
1230         if (bond_info->rlb_enabled) {
1231                 rlb_deinitialize(bond);
1232         }
1233 }
1234
1235 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1236 {
1237         struct bonding *bond = netdev_priv(bond_dev);
1238         struct ethhdr *eth_data;
1239         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1240         struct slave *tx_slave = NULL;
1241         static const __be32 ip_bcast = htonl(0xffffffff);
1242         int hash_size = 0;
1243         int do_tx_balance = 1;
1244         u32 hash_index = 0;
1245         const u8 *hash_start = NULL;
1246         int res = 1;
1247         struct ipv6hdr *ip6hdr;
1248
1249         skb_reset_mac_header(skb);
1250         eth_data = eth_hdr(skb);
1251
1252         /* make sure that the curr_active_slave do not change during tx
1253          */
1254         read_lock(&bond->curr_slave_lock);
1255
1256         switch (ntohs(skb->protocol)) {
1257         case ETH_P_IP: {
1258                 const struct iphdr *iph = ip_hdr(skb);
1259
1260                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast) ||
1261                     (iph->daddr == ip_bcast) ||
1262                     (iph->protocol == IPPROTO_IGMP)) {
1263                         do_tx_balance = 0;
1264                         break;
1265                 }
1266                 hash_start = (char *)&(iph->daddr);
1267                 hash_size = sizeof(iph->daddr);
1268         }
1269                 break;
1270         case ETH_P_IPV6:
1271                 /* IPv6 doesn't really use broadcast mac address, but leave
1272                  * that here just in case.
1273                  */
1274                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast)) {
1275                         do_tx_balance = 0;
1276                         break;
1277                 }
1278
1279                 /* IPv6 uses all-nodes multicast as an equivalent to
1280                  * broadcasts in IPv4.
1281                  */
1282                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1283                         do_tx_balance = 0;
1284                         break;
1285                 }
1286
1287                 /* Additianally, DAD probes should not be tx-balanced as that
1288                  * will lead to false positives for duplicate addresses and
1289                  * prevent address configuration from working.
1290                  */
1291                 ip6hdr = ipv6_hdr(skb);
1292                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1293                         do_tx_balance = 0;
1294                         break;
1295                 }
1296
1297                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1298                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1299                 break;
1300         case ETH_P_IPX:
1301                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1302                         /* something is wrong with this packet */
1303                         do_tx_balance = 0;
1304                         break;
1305                 }
1306
1307                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1308                         /* The only protocol worth balancing in
1309                          * this family since it has an "ARP" like
1310                          * mechanism
1311                          */
1312                         do_tx_balance = 0;
1313                         break;
1314                 }
1315
1316                 hash_start = (char*)eth_data->h_dest;
1317                 hash_size = ETH_ALEN;
1318                 break;
1319         case ETH_P_ARP:
1320                 do_tx_balance = 0;
1321                 if (bond_info->rlb_enabled) {
1322                         tx_slave = rlb_arp_xmit(skb, bond);
1323                 }
1324                 break;
1325         default:
1326                 do_tx_balance = 0;
1327                 break;
1328         }
1329
1330         if (do_tx_balance) {
1331                 hash_index = _simple_hash(hash_start, hash_size);
1332                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1333         }
1334
1335         if (!tx_slave) {
1336                 /* unbalanced or unassigned, send through primary */
1337                 tx_slave = bond->curr_active_slave;
1338                 bond_info->unbalanced_load += skb->len;
1339         }
1340
1341         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1342                 if (tx_slave != bond->curr_active_slave) {
1343                         memcpy(eth_data->h_source,
1344                                tx_slave->dev->dev_addr,
1345                                ETH_ALEN);
1346                 }
1347
1348                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1349         } else {
1350                 if (tx_slave) {
1351                         _lock_tx_hashtbl(bond);
1352                         __tlb_clear_slave(bond, tx_slave, 0);
1353                         _unlock_tx_hashtbl(bond);
1354                 }
1355         }
1356
1357         if (res) {
1358                 /* no suitable interface, frame not sent */
1359                 dev_kfree_skb(skb);
1360         }
1361         read_unlock(&bond->curr_slave_lock);
1362
1363         return NETDEV_TX_OK;
1364 }
1365
1366 void bond_alb_monitor(struct work_struct *work)
1367 {
1368         struct bonding *bond = container_of(work, struct bonding,
1369                                             alb_work.work);
1370         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1371         struct slave *slave;
1372         int i;
1373
1374         read_lock(&bond->lock);
1375
1376         if (bond->slave_cnt == 0) {
1377                 bond_info->tx_rebalance_counter = 0;
1378                 bond_info->lp_counter = 0;
1379                 goto re_arm;
1380         }
1381
1382         bond_info->tx_rebalance_counter++;
1383         bond_info->lp_counter++;
1384
1385         /* send learning packets */
1386         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1387                 /* change of curr_active_slave involves swapping of mac addresses.
1388                  * in order to avoid this swapping from happening while
1389                  * sending the learning packets, the curr_slave_lock must be held for
1390                  * read.
1391                  */
1392                 read_lock(&bond->curr_slave_lock);
1393
1394                 bond_for_each_slave(bond, slave, i) {
1395                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1396                 }
1397
1398                 read_unlock(&bond->curr_slave_lock);
1399
1400                 bond_info->lp_counter = 0;
1401         }
1402
1403         /* rebalance tx traffic */
1404         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1405
1406                 read_lock(&bond->curr_slave_lock);
1407
1408                 bond_for_each_slave(bond, slave, i) {
1409                         tlb_clear_slave(bond, slave, 1);
1410                         if (slave == bond->curr_active_slave) {
1411                                 SLAVE_TLB_INFO(slave).load =
1412                                         bond_info->unbalanced_load /
1413                                                 BOND_TLB_REBALANCE_INTERVAL;
1414                                 bond_info->unbalanced_load = 0;
1415                         }
1416                 }
1417
1418                 read_unlock(&bond->curr_slave_lock);
1419
1420                 bond_info->tx_rebalance_counter = 0;
1421         }
1422
1423         /* handle rlb stuff */
1424         if (bond_info->rlb_enabled) {
1425                 if (bond_info->primary_is_promisc &&
1426                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1427
1428                         /*
1429                          * dev_set_promiscuity requires rtnl and
1430                          * nothing else.  Avoid race with bond_close.
1431                          */
1432                         read_unlock(&bond->lock);
1433                         if (!rtnl_trylock()) {
1434                                 read_lock(&bond->lock);
1435                                 goto re_arm;
1436                         }
1437
1438                         bond_info->rlb_promisc_timeout_counter = 0;
1439
1440                         /* If the primary was set to promiscuous mode
1441                          * because a slave was disabled then
1442                          * it can now leave promiscuous mode.
1443                          */
1444                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1445                         bond_info->primary_is_promisc = 0;
1446
1447                         rtnl_unlock();
1448                         read_lock(&bond->lock);
1449                 }
1450
1451                 if (bond_info->rlb_rebalance) {
1452                         bond_info->rlb_rebalance = 0;
1453                         rlb_rebalance(bond);
1454                 }
1455
1456                 /* check if clients need updating */
1457                 if (bond_info->rx_ntt) {
1458                         if (bond_info->rlb_update_delay_counter) {
1459                                 --bond_info->rlb_update_delay_counter;
1460                         } else {
1461                                 rlb_update_rx_clients(bond);
1462                                 if (bond_info->rlb_update_retry_counter) {
1463                                         --bond_info->rlb_update_retry_counter;
1464                                 } else {
1465                                         bond_info->rx_ntt = 0;
1466                                 }
1467                         }
1468                 }
1469         }
1470
1471 re_arm:
1472         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1473
1474         read_unlock(&bond->lock);
1475 }
1476
1477 /* assumption: called before the slave is attached to the bond
1478  * and not locked by the bond lock
1479  */
1480 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1481 {
1482         int res;
1483
1484         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1485         if (res) {
1486                 return res;
1487         }
1488
1489         /* caller must hold the bond lock for write since the mac addresses
1490          * are compared and may be swapped.
1491          */
1492         read_lock(&bond->lock);
1493
1494         res = alb_handle_addr_collision_on_attach(bond, slave);
1495
1496         read_unlock(&bond->lock);
1497
1498         if (res) {
1499                 return res;
1500         }
1501
1502         tlb_init_slave(slave);
1503
1504         /* order a rebalance ASAP */
1505         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1506
1507         if (bond->alb_info.rlb_enabled) {
1508                 bond->alb_info.rlb_rebalance = 1;
1509         }
1510
1511         return 0;
1512 }
1513
1514 /*
1515  * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1516  * if necessary.
1517  *
1518  * Caller must hold RTNL and no other locks
1519  */
1520 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1521 {
1522         if (bond->slave_cnt > 1) {
1523                 alb_change_hw_addr_on_detach(bond, slave);
1524         }
1525
1526         tlb_clear_slave(bond, slave, 0);
1527
1528         if (bond->alb_info.rlb_enabled) {
1529                 bond->alb_info.next_rx_slave = NULL;
1530                 rlb_clear_slave(bond, slave);
1531         }
1532 }
1533
1534 /* Caller must hold bond lock for read */
1535 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1536 {
1537         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1538
1539         if (link == BOND_LINK_DOWN) {
1540                 tlb_clear_slave(bond, slave, 0);
1541                 if (bond->alb_info.rlb_enabled) {
1542                         rlb_clear_slave(bond, slave);
1543                 }
1544         } else if (link == BOND_LINK_UP) {
1545                 /* order a rebalance ASAP */
1546                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1547                 if (bond->alb_info.rlb_enabled) {
1548                         bond->alb_info.rlb_rebalance = 1;
1549                         /* If the updelay module parameter is smaller than the
1550                          * forwarding delay of the switch the rebalance will
1551                          * not work because the rebalance arp replies will
1552                          * not be forwarded to the clients..
1553                          */
1554                 }
1555         }
1556 }
1557
1558 /**
1559  * bond_alb_handle_active_change - assign new curr_active_slave
1560  * @bond: our bonding struct
1561  * @new_slave: new slave to assign
1562  *
1563  * Set the bond->curr_active_slave to @new_slave and handle
1564  * mac address swapping and promiscuity changes as needed.
1565  *
1566  * If new_slave is NULL, caller must hold curr_slave_lock or
1567  * bond->lock for write.
1568  *
1569  * If new_slave is not NULL, caller must hold RTNL, bond->lock for
1570  * read and curr_slave_lock for write.  Processing here may sleep, so
1571  * no other locks may be held.
1572  */
1573 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1574         __releases(&bond->curr_slave_lock)
1575         __releases(&bond->lock)
1576         __acquires(&bond->lock)
1577         __acquires(&bond->curr_slave_lock)
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 (!compare_ether_addr_64bits(tmp_slave->dev->dev_addr,
1607                                                        bond->dev->dev_addr)) {
1608                                 swap_slave = tmp_slave;
1609                                 break;
1610                         }
1611                 }
1612         }
1613
1614         /*
1615          * Arrange for swap_slave and new_slave to temporarily be
1616          * ignored so we can mess with their MAC addresses without
1617          * fear of interference from transmit activity.
1618          */
1619         if (swap_slave) {
1620                 tlb_clear_slave(bond, swap_slave, 1);
1621         }
1622         tlb_clear_slave(bond, new_slave, 1);
1623
1624         write_unlock_bh(&bond->curr_slave_lock);
1625         read_unlock(&bond->lock);
1626
1627         ASSERT_RTNL();
1628
1629         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1630         if (swap_slave) {
1631                 /* swap mac address */
1632                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1633         } else {
1634                 /* set the new_slave to the bond mac address */
1635                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1636         }
1637
1638         if (swap_slave) {
1639                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1640                 read_lock(&bond->lock);
1641         } else {
1642                 read_lock(&bond->lock);
1643                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1644         }
1645
1646         write_lock_bh(&bond->curr_slave_lock);
1647 }
1648
1649 /*
1650  * Called with RTNL
1651  */
1652 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1653         __acquires(&bond->lock)
1654         __releases(&bond->lock)
1655 {
1656         struct bonding *bond = netdev_priv(bond_dev);
1657         struct sockaddr *sa = addr;
1658         struct slave *slave, *swap_slave;
1659         int res;
1660         int i;
1661
1662         if (!is_valid_ether_addr(sa->sa_data)) {
1663                 return -EADDRNOTAVAIL;
1664         }
1665
1666         res = alb_set_mac_address(bond, addr);
1667         if (res) {
1668                 return res;
1669         }
1670
1671         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1672
1673         /* If there is no curr_active_slave there is nothing else to do.
1674          * Otherwise we'll need to pass the new address to it and handle
1675          * duplications.
1676          */
1677         if (!bond->curr_active_slave) {
1678                 return 0;
1679         }
1680
1681         swap_slave = NULL;
1682
1683         bond_for_each_slave(bond, slave, i) {
1684                 if (!compare_ether_addr_64bits(slave->dev->dev_addr,
1685                                                bond_dev->dev_addr)) {
1686                         swap_slave = slave;
1687                         break;
1688                 }
1689         }
1690
1691         if (swap_slave) {
1692                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1693                 alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1694         } else {
1695                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr);
1696
1697                 read_lock(&bond->lock);
1698                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1699                 if (bond->alb_info.rlb_enabled) {
1700                         /* inform clients mac address has changed */
1701                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1702                 }
1703                 read_unlock(&bond->lock);
1704         }
1705
1706         return 0;
1707 }
1708
1709 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1710 {
1711         if (bond->alb_info.current_alb_vlan &&
1712             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1713                 bond->alb_info.current_alb_vlan = NULL;
1714         }
1715
1716         if (bond->alb_info.rlb_enabled) {
1717                 rlb_clear_vlan(bond, vlan_id);
1718         }
1719 }
1720