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, see <http://www.gnu.org/licenses/>.
  16  *
  17  * The full GNU General Public License is included in this distribution in the
  18  * file called LICENSE.
  19  *
  20  */
  21
  22 #include <linux/skbuff.h>
  23 #include <linux/netdevice.h>
  24 #include <linux/etherdevice.h>
  25 #include <linux/pkt_sched.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/slab.h>
  28 #include <linux/timer.h>
  29 #include <linux/ip.h>
  30 #include <linux/ipv6.h>
  31 #include <linux/if_arp.h>
  32 #include <linux/if_ether.h>
  33 #include <linux/if_bonding.h>
  34 #include <linux/if_vlan.h>
  35 #include <linux/in.h>
  36 #include <net/ipx.h>
  37 #include <net/arp.h>
  38 #include <net/ipv6.h>
  39 #include <asm/byteorder.h>
  40 #include "bonding.h"
  41 #include "bond_alb.h"
  42
  43
  44
  45 #ifndef __long_aligned
  46 #define __long_aligned __attribute__((aligned((sizeof(long)))))
  47 #endif
  48 static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
  49         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  50 };
  51 static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
  52         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  53 };
  54 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  55
  56 #pragma pack(1)
  57 struct learning_pkt {
  58         u8 mac_dst[ETH_ALEN];
  59         u8 mac_src[ETH_ALEN];
  60         __be16 type;
  61         u8 padding[ETH_ZLEN - ETH_HLEN];
  62 };
  63
  64 struct arp_pkt {
  65         __be16  hw_addr_space;
  66         __be16  prot_addr_space;
  67         u8      hw_addr_len;
  68         u8      prot_addr_len;
  69         __be16  op_code;
  70         u8      mac_src[ETH_ALEN];      /* sender hardware address */
  71         __be32  ip_src;                 /* sender IP address */
  72         u8      mac_dst[ETH_ALEN];      /* target hardware address */
  73         __be32  ip_dst;                 /* target IP address */
  74 };
  75 #pragma pack()
  76
  77 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
  78 {
  79         return (struct arp_pkt *)skb_network_header(skb);
  80 }
  81
  82 /* Forward declaration */
  83 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
  84                                       bool strict_match);
  85 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  86 static void rlb_src_unlink(struct bonding *bond, u32 index);
  87 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  88                          u32 ip_dst_hash);
  89
  90 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  91 {
  92         int i;
  93         u8 hash = 0;
  94
  95         for (i = 0; i < hash_size; i++)
  96                 hash ^= hash_start[i];
  97
  98         return hash;
  99 }
 100
 101 /*********************** tlb specific functions ***************************/
 102
 103 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 104 {
 105         if (save_load) {
 106                 entry->load_history = 1 + entry->tx_bytes /
 107                                       BOND_TLB_REBALANCE_INTERVAL;
 108                 entry->tx_bytes = 0;
 109         }
 110
 111         entry->tx_slave = NULL;
 112         entry->next = TLB_NULL_INDEX;
 113         entry->prev = TLB_NULL_INDEX;
 114 }
 115
 116 static inline void tlb_init_slave(struct slave *slave)
 117 {
 118         SLAVE_TLB_INFO(slave).load = 0;
 119         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 120 }
 121
 122 static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
 123                          int save_load)
 124 {
 125         struct tlb_client_info *tx_hash_table;
 126         u32 index;
 127
 128         /* clear slave from tx_hashtbl */
 129         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 130
 131         /* skip this if we've already freed the tx hash table */
 132         if (tx_hash_table) {
 133                 index = SLAVE_TLB_INFO(slave).head;
 134                 while (index != TLB_NULL_INDEX) {
 135                         u32 next_index = tx_hash_table[index].next;
 136                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 137                         index = next_index;
 138                 }
 139         }
 140
 141         tlb_init_slave(slave);
 142 }
 143
 144 static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 145                          int save_load)
 146 {
 147         spin_lock_bh(&bond->mode_lock);
 148         __tlb_clear_slave(bond, slave, save_load);
 149         spin_unlock_bh(&bond->mode_lock);
 150 }
 151
 152 /* Must be called before starting the monitor timer */
 153 static int tlb_initialize(struct bonding *bond)
 154 {
 155         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 156         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 157         struct tlb_client_info *new_hashtbl;
 158         int i;
 159
 160         new_hashtbl = kzalloc(size, GFP_KERNEL);
 161         if (!new_hashtbl)
 162                 return -1;
 163
 164         spin_lock_bh(&bond->mode_lock);
 165
 166         bond_info->tx_hashtbl = new_hashtbl;
 167
 168         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
 169                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 170
 171         spin_unlock_bh(&bond->mode_lock);
 172
 173         return 0;
 174 }
 175
 176 /* Must be called only after all slaves have been released */
 177 static void tlb_deinitialize(struct bonding *bond)
 178 {
 179         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 180
 181         spin_lock_bh(&bond->mode_lock);
 182
 183         kfree(bond_info->tx_hashtbl);
 184         bond_info->tx_hashtbl = NULL;
 185
 186         spin_unlock_bh(&bond->mode_lock);
 187 }
 188
 189 static long long compute_gap(struct slave *slave)
 190 {
 191         return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 192                (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 193 }
 194
 195 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 196 {
 197         struct slave *slave, *least_loaded;
 198         struct list_head *iter;
 199         long long max_gap;
 200
 201         least_loaded = NULL;
 202         max_gap = LLONG_MIN;
 203
 204         /* Find the slave with the largest gap */
 205         bond_for_each_slave_rcu(bond, slave, iter) {
 206                 if (bond_slave_can_tx(slave)) {
 207                         long long gap = compute_gap(slave);
 208
 209                         if (max_gap < gap) {
 210                                 least_loaded = slave;
 211                                 max_gap = gap;
 212                         }
 213                 }
 214         }
 215
 216         return least_loaded;
 217 }
 218
 219 static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 220                                                 u32 skb_len)
 221 {
 222         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 223         struct tlb_client_info *hash_table;
 224         struct slave *assigned_slave;
 225
 226         hash_table = bond_info->tx_hashtbl;
 227         assigned_slave = hash_table[hash_index].tx_slave;
 228         if (!assigned_slave) {
 229                 assigned_slave = tlb_get_least_loaded_slave(bond);
 230
 231                 if (assigned_slave) {
 232                         struct tlb_slave_info *slave_info =
 233                                 &(SLAVE_TLB_INFO(assigned_slave));
 234                         u32 next_index = slave_info->head;
 235
 236                         hash_table[hash_index].tx_slave = assigned_slave;
 237                         hash_table[hash_index].next = next_index;
 238                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 239
 240                         if (next_index != TLB_NULL_INDEX)
 241                                 hash_table[next_index].prev = hash_index;
 242
 243                         slave_info->head = hash_index;
 244                         slave_info->load +=
 245                                 hash_table[hash_index].load_history;
 246                 }
 247         }
 248
 249         if (assigned_slave)
 250                 hash_table[hash_index].tx_bytes += skb_len;
 251
 252         return assigned_slave;
 253 }
 254
 255 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 256                                         u32 skb_len)
 257 {
 258         struct slave *tx_slave;
 259
 260         /* We don't need to disable softirq here, becase
 261          * tlb_choose_channel() is only called by bond_alb_xmit()
 262          * which already has softirq disabled.
 263          */
 264         spin_lock(&bond->mode_lock);
 265         tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 266         spin_unlock(&bond->mode_lock);
 267
 268         return tx_slave;
 269 }
 270
 271 /*********************** rlb specific functions ***************************/
 272
 273 /* when an ARP REPLY is received from a client update its info
 274  * in the rx_hashtbl
 275  */
 276 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 277 {
 278         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 279         struct rlb_client_info *client_info;
 280         u32 hash_index;
 281
 282         spin_lock_bh(&bond->mode_lock);
 283
 284         hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 285         client_info = &(bond_info->rx_hashtbl[hash_index]);
 286
 287         if ((client_info->assigned) &&
 288             (client_info->ip_src == arp->ip_dst) &&
 289             (client_info->ip_dst == arp->ip_src) &&
 290             (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
 291                 /* update the clients MAC address */
 292                 ether_addr_copy(client_info->mac_dst, arp->mac_src);
 293                 client_info->ntt = 1;
 294                 bond_info->rx_ntt = 1;
 295         }
 296
 297         spin_unlock_bh(&bond->mode_lock);
 298 }
 299
 300 static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
 301                         struct slave *slave)
 302 {
 303         struct arp_pkt *arp, _arp;
 304
 305         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 306                 goto out;
 307
 308         arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
 309         if (!arp)
 310                 goto out;
 311
 312         /* We received an ARP from arp->ip_src.
 313          * We might have used this IP address previously (on the bonding host
 314          * itself or on a system that is bridged together with the bond).
 315          * However, if arp->mac_src is different than what is stored in
 316          * rx_hashtbl, some other host is now using the IP and we must prevent
 317          * sending out client updates with this IP address and the old MAC
 318          * address.
 319          * Clean up all hash table entries that have this address as ip_src but
 320          * have a different mac_src.
 321          */
 322         rlb_purge_src_ip(bond, arp);
 323
 324         if (arp->op_code == htons(ARPOP_REPLY)) {
 325                 /* update rx hash table for this ARP */
 326                 rlb_update_entry_from_arp(bond, arp);
 327                 netdev_dbg(bond->dev, "Server received an ARP Reply from client\n");
 328         }
 329 out:
 330         return RX_HANDLER_ANOTHER;
 331 }
 332
 333 /* Caller must hold rcu_read_lock() */
 334 static struct slave *__rlb_next_rx_slave(struct bonding *bond)
 335 {
 336         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 337         struct slave *before = NULL, *rx_slave = NULL, *slave;
 338         struct list_head *iter;
 339         bool found = false;
 340
 341         bond_for_each_slave_rcu(bond, slave, iter) {
 342                 if (!bond_slave_can_tx(slave))
 343                         continue;
 344                 if (!found) {
 345                         if (!before || before->speed < slave->speed)
 346                                 before = slave;
 347                 } else {
 348                         if (!rx_slave || rx_slave->speed < slave->speed)
 349                                 rx_slave = slave;
 350                 }
 351                 if (slave == bond_info->rx_slave)
 352                         found = true;
 353         }
 354         /* we didn't find anything after the current or we have something
 355          * better before and up to the current slave
 356          */
 357         if (!rx_slave || (before && rx_slave->speed < before->speed))
 358                 rx_slave = before;
 359
 360         if (rx_slave)
 361                 bond_info->rx_slave = rx_slave;
 362
 363         return rx_slave;
 364 }
 365
 366 /* Caller must hold RTNL, rcu_read_lock is obtained only to silence checkers */
 367 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 368 {
 369         struct slave *rx_slave;
 370
 371         ASSERT_RTNL();
 372
 373         rcu_read_lock();
 374         rx_slave = __rlb_next_rx_slave(bond);
 375         rcu_read_unlock();
 376
 377         return rx_slave;
 378 }
 379
 380 /* teach the switch the mac of a disabled slave
 381  * on the primary for fault tolerance
 382  *
 383  * Caller must hold RTNL
 384  */
 385 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 386 {
 387         struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
 388
 389         if (!curr_active)
 390                 return;
 391
 392         if (!bond->alb_info.primary_is_promisc) {
 393                 if (!dev_set_promiscuity(curr_active->dev, 1))
 394                         bond->alb_info.primary_is_promisc = 1;
 395                 else
 396                         bond->alb_info.primary_is_promisc = 0;
 397         }
 398
 399         bond->alb_info.rlb_promisc_timeout_counter = 0;
 400
 401         alb_send_learning_packets(curr_active, addr, true);
 402 }
 403
 404 /* slave being removed should not be active at this point
 405  *
 406  * Caller must hold rtnl.
 407  */
 408 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 409 {
 410         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 411         struct rlb_client_info *rx_hash_table;
 412         u32 index, next_index;
 413
 414         /* clear slave from rx_hashtbl */
 415         spin_lock_bh(&bond->mode_lock);
 416
 417         rx_hash_table = bond_info->rx_hashtbl;
 418         index = bond_info->rx_hashtbl_used_head;
 419         for (; index != RLB_NULL_INDEX; index = next_index) {
 420                 next_index = rx_hash_table[index].used_next;
 421                 if (rx_hash_table[index].slave == slave) {
 422                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 423
 424                         if (assigned_slave) {
 425                                 rx_hash_table[index].slave = assigned_slave;
 426                                 if (!ether_addr_equal_64bits(rx_hash_table[index].mac_dst,
 427                                                              mac_bcast)) {
 428                                         bond_info->rx_hashtbl[index].ntt = 1;
 429                                         bond_info->rx_ntt = 1;
 430                                         /* A slave has been removed from the
 431                                          * table because it is either disabled
 432                                          * or being released. We must retry the
 433                                          * update to avoid clients from not
 434                                          * being updated & disconnecting when
 435                                          * there is stress
 436                                          */
 437                                         bond_info->rlb_update_retry_counter =
 438                                                 RLB_UPDATE_RETRY;
 439                                 }
 440                         } else {  /* there is no active slave */
 441                                 rx_hash_table[index].slave = NULL;
 442                         }
 443                 }
 444         }
 445
 446         spin_unlock_bh(&bond->mode_lock);
 447
 448         if (slave != rtnl_dereference(bond->curr_active_slave))
 449                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 450 }
 451
 452 static void rlb_update_client(struct rlb_client_info *client_info)
 453 {
 454         int i;
 455
 456         if (!client_info->slave)
 457                 return;
 458
 459         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 460                 struct sk_buff *skb;
 461
 462                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 463                                  client_info->ip_dst,
 464                                  client_info->slave->dev,
 465                                  client_info->ip_src,
 466                                  client_info->mac_dst,
 467                                  client_info->slave->dev->dev_addr,
 468                                  client_info->mac_dst);
 469                 if (!skb) {
 470                         netdev_err(client_info->slave->bond->dev,
 471                                    "failed to create an ARP packet\n");
 472                         continue;
 473                 }
 474
 475                 skb->dev = client_info->slave->dev;
 476
 477                 if (client_info->vlan_id) {
 478                         skb = vlan_put_tag(skb, htons(ETH_P_8021Q), client_info->vlan_id);
 479                         if (!skb) {
 480                                 netdev_err(client_info->slave->bond->dev,
 481                                            "failed to insert VLAN tag\n");
 482                                 continue;
 483                         }
 484                 }
 485
 486                 arp_xmit(skb);
 487         }
 488 }
 489
 490 /* sends ARP REPLIES that update the clients that need updating */
 491 static void rlb_update_rx_clients(struct bonding *bond)
 492 {
 493         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 494         struct rlb_client_info *client_info;
 495         u32 hash_index;
 496
 497         spin_lock_bh(&bond->mode_lock);
 498
 499         hash_index = bond_info->rx_hashtbl_used_head;
 500         for (; hash_index != RLB_NULL_INDEX;
 501              hash_index = client_info->used_next) {
 502                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 503                 if (client_info->ntt) {
 504                         rlb_update_client(client_info);
 505                         if (bond_info->rlb_update_retry_counter == 0)
 506                                 client_info->ntt = 0;
 507                 }
 508         }
 509
 510         /* do not update the entries again until this counter is zero so that
 511          * not to confuse the clients.
 512          */
 513         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 514
 515         spin_unlock_bh(&bond->mode_lock);
 516 }
 517
 518 /* The slave was assigned a new mac address - update the clients */
 519 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 520 {
 521         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 522         struct rlb_client_info *client_info;
 523         int ntt = 0;
 524         u32 hash_index;
 525
 526         spin_lock_bh(&bond->mode_lock);
 527
 528         hash_index = bond_info->rx_hashtbl_used_head;
 529         for (; hash_index != RLB_NULL_INDEX;
 530              hash_index = client_info->used_next) {
 531                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 532
 533                 if ((client_info->slave == slave) &&
 534                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 535                         client_info->ntt = 1;
 536                         ntt = 1;
 537                 }
 538         }
 539
 540         /* update the team's flag only after the whole iteration */
 541         if (ntt) {
 542                 bond_info->rx_ntt = 1;
 543                 /* fasten the change */
 544                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 545         }
 546
 547         spin_unlock_bh(&bond->mode_lock);
 548 }
 549
 550 /* mark all clients using src_ip to be updated */
 551 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 552 {
 553         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 554         struct rlb_client_info *client_info;
 555         u32 hash_index;
 556
 557         spin_lock(&bond->mode_lock);
 558
 559         hash_index = bond_info->rx_hashtbl_used_head;
 560         for (; hash_index != RLB_NULL_INDEX;
 561              hash_index = client_info->used_next) {
 562                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 563
 564                 if (!client_info->slave) {
 565                         netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
 566                         continue;
 567                 }
 568                 /* update all clients using this src_ip, that are not assigned
 569                  * to the team's address (curr_active_slave) and have a known
 570                  * unicast mac address.
 571                  */
 572                 if ((client_info->ip_src == src_ip) &&
 573                     !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 574                                              bond->dev->dev_addr) &&
 575                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 576                         client_info->ntt = 1;
 577                         bond_info->rx_ntt = 1;
 578                 }
 579         }
 580
 581         spin_unlock(&bond->mode_lock);
 582 }
 583
 584 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 585 {
 586         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 587         struct arp_pkt *arp = arp_pkt(skb);
 588         struct slave *assigned_slave, *curr_active_slave;
 589         struct rlb_client_info *client_info;
 590         u32 hash_index = 0;
 591
 592         spin_lock(&bond->mode_lock);
 593
 594         curr_active_slave = rcu_dereference(bond->curr_active_slave);
 595
 596         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 597         client_info = &(bond_info->rx_hashtbl[hash_index]);
 598
 599         if (client_info->assigned) {
 600                 if ((client_info->ip_src == arp->ip_src) &&
 601                     (client_info->ip_dst == arp->ip_dst)) {
 602                         /* the entry is already assigned to this client */
 603                         if (!ether_addr_equal_64bits(arp->mac_dst, mac_bcast)) {
 604                                 /* update mac address from arp */
 605                                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 606                         }
 607                         ether_addr_copy(client_info->mac_src, arp->mac_src);
 608
 609                         assigned_slave = client_info->slave;
 610                         if (assigned_slave) {
 611                                 spin_unlock(&bond->mode_lock);
 612                                 return assigned_slave;
 613                         }
 614                 } else {
 615                         /* the entry is already assigned to some other client,
 616                          * move the old client to primary (curr_active_slave) so
 617                          * that the new client can be assigned to this entry.
 618                          */
 619                         if (curr_active_slave &&
 620                             client_info->slave != curr_active_slave) {
 621                                 client_info->slave = curr_active_slave;
 622                                 rlb_update_client(client_info);
 623                         }
 624                 }
 625         }
 626         /* assign a new slave */
 627         assigned_slave = __rlb_next_rx_slave(bond);
 628
 629         if (assigned_slave) {
 630                 if (!(client_info->assigned &&
 631                       client_info->ip_src == arp->ip_src)) {
 632                         /* ip_src is going to be updated,
 633                          * fix the src hash list
 634                          */
 635                         u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 636                                                     sizeof(arp->ip_src));
 637                         rlb_src_unlink(bond, hash_index);
 638                         rlb_src_link(bond, hash_src, hash_index);
 639                 }
 640
 641                 client_info->ip_src = arp->ip_src;
 642                 client_info->ip_dst = arp->ip_dst;
 643                 /* arp->mac_dst is broadcast for arp reqeusts.
 644                  * will be updated with clients actual unicast mac address
 645                  * upon receiving an arp reply.
 646                  */
 647                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 648                 ether_addr_copy(client_info->mac_src, arp->mac_src);
 649                 client_info->slave = assigned_slave;
 650
 651                 if (!ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 652                         client_info->ntt = 1;
 653                         bond->alb_info.rx_ntt = 1;
 654                 } else {
 655                         client_info->ntt = 0;
 656                 }
 657
 658                 if (vlan_get_tag(skb, &client_info->vlan_id))
 659                         client_info->vlan_id = 0;
 660
 661                 if (!client_info->assigned) {
 662                         u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 663                         bond_info->rx_hashtbl_used_head = hash_index;
 664                         client_info->used_next = prev_tbl_head;
 665                         if (prev_tbl_head != RLB_NULL_INDEX) {
 666                                 bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 667                                         hash_index;
 668                         }
 669                         client_info->assigned = 1;
 670                 }
 671         }
 672
 673         spin_unlock(&bond->mode_lock);
 674
 675         return assigned_slave;
 676 }
 677
 678 /* chooses (and returns) transmit channel for arp reply
 679  * does not choose channel for other arp types since they are
 680  * sent on the curr_active_slave
 681  */
 682 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 683 {
 684         struct arp_pkt *arp = arp_pkt(skb);
 685         struct slave *tx_slave = NULL;
 686
 687         /* Don't modify or load balance ARPs that do not originate locally
 688          * (e.g.,arrive via a bridge).
 689          */
 690         if (!bond_slave_has_mac_rx(bond, arp->mac_src))
 691                 return NULL;
 692
 693         if (arp->op_code == htons(ARPOP_REPLY)) {
 694                 /* the arp must be sent on the selected rx channel */
 695                 tx_slave = rlb_choose_channel(skb, bond);
 696                 if (tx_slave)
 697                         ether_addr_copy(arp->mac_src, tx_slave->dev->dev_addr);
 698                 netdev_dbg(bond->dev, "Server sent ARP Reply packet\n");
 699         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 700                 /* Create an entry in the rx_hashtbl for this client as a
 701                  * place holder.
 702                  * When the arp reply is received the entry will be updated
 703                  * with the correct unicast address of the client.
 704                  */
 705                 rlb_choose_channel(skb, bond);
 706
 707                 /* The ARP reply packets must be delayed so that
 708                  * they can cancel out the influence of the ARP request.
 709                  */
 710                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 711
 712                 /* arp requests are broadcast and are sent on the primary
 713                  * the arp request will collapse all clients on the subnet to
 714                  * the primary slave. We must register these clients to be
 715                  * updated with their assigned mac.
 716                  */
 717                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 718                 netdev_dbg(bond->dev, "Server sent ARP Request packet\n");
 719         }
 720
 721         return tx_slave;
 722 }
 723
 724 static void rlb_rebalance(struct bonding *bond)
 725 {
 726         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 727         struct slave *assigned_slave;
 728         struct rlb_client_info *client_info;
 729         int ntt;
 730         u32 hash_index;
 731
 732         spin_lock_bh(&bond->mode_lock);
 733
 734         ntt = 0;
 735         hash_index = bond_info->rx_hashtbl_used_head;
 736         for (; hash_index != RLB_NULL_INDEX;
 737              hash_index = client_info->used_next) {
 738                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 739                 assigned_slave = __rlb_next_rx_slave(bond);
 740                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 741                         client_info->slave = assigned_slave;
 742                         client_info->ntt = 1;
 743                         ntt = 1;
 744                 }
 745         }
 746
 747         /* update the team's flag only after the whole iteration */
 748         if (ntt)
 749                 bond_info->rx_ntt = 1;
 750         spin_unlock_bh(&bond->mode_lock);
 751 }
 752
 753 /* Caller must hold mode_lock */
 754 static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 755 {
 756         entry->used_next = RLB_NULL_INDEX;
 757         entry->used_prev = RLB_NULL_INDEX;
 758         entry->assigned = 0;
 759         entry->slave = NULL;
 760         entry->vlan_id = 0;
 761 }
 762 static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 763 {
 764         entry->src_first = RLB_NULL_INDEX;
 765         entry->src_prev = RLB_NULL_INDEX;
 766         entry->src_next = RLB_NULL_INDEX;
 767 }
 768
 769 static void rlb_init_table_entry(struct rlb_client_info *entry)
 770 {
 771         memset(entry, 0, sizeof(struct rlb_client_info));
 772         rlb_init_table_entry_dst(entry);
 773         rlb_init_table_entry_src(entry);
 774 }
 775
 776 static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 777 {
 778         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 779         u32 next_index = bond_info->rx_hashtbl[index].used_next;
 780         u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 781
 782         if (index == bond_info->rx_hashtbl_used_head)
 783                 bond_info->rx_hashtbl_used_head = next_index;
 784         if (prev_index != RLB_NULL_INDEX)
 785                 bond_info->rx_hashtbl[prev_index].used_next = next_index;
 786         if (next_index != RLB_NULL_INDEX)
 787                 bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 788 }
 789
 790 /* unlink a rlb hash table entry from the src list */
 791 static void rlb_src_unlink(struct bonding *bond, u32 index)
 792 {
 793         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 794         u32 next_index = bond_info->rx_hashtbl[index].src_next;
 795         u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 796
 797         bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 798         bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 799
 800         if (next_index != RLB_NULL_INDEX)
 801                 bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 802
 803         if (prev_index == RLB_NULL_INDEX)
 804                 return;
 805
 806         /* is prev_index pointing to the head of this list? */
 807         if (bond_info->rx_hashtbl[prev_index].src_first == index)
 808                 bond_info->rx_hashtbl[prev_index].src_first = next_index;
 809         else
 810                 bond_info->rx_hashtbl[prev_index].src_next = next_index;
 811
 812 }
 813
 814 static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 815 {
 816         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 817         struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 818
 819         rlb_delete_table_entry_dst(bond, index);
 820         rlb_init_table_entry_dst(entry);
 821
 822         rlb_src_unlink(bond, index);
 823 }
 824
 825 /* add the rx_hashtbl[ip_dst_hash] entry to the list
 826  * of entries with identical ip_src_hash
 827  */
 828 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 829 {
 830         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 831         u32 next;
 832
 833         bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 834         next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 835         bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 836         if (next != RLB_NULL_INDEX)
 837                 bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 838         bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 839 }
 840
 841 /* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
 842  * not match arp->mac_src
 843  */
 844 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 845 {
 846         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 847         u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 848         u32 index;
 849
 850         spin_lock_bh(&bond->mode_lock);
 851
 852         index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 853         while (index != RLB_NULL_INDEX) {
 854                 struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 855                 u32 next_index = entry->src_next;
 856                 if (entry->ip_src == arp->ip_src &&
 857                     !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 858                                 rlb_delete_table_entry(bond, index);
 859                 index = next_index;
 860         }
 861         spin_unlock_bh(&bond->mode_lock);
 862 }
 863
 864 static int rlb_initialize(struct bonding *bond)
 865 {
 866         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 867         struct rlb_client_info  *new_hashtbl;
 868         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 869         int i;
 870
 871         new_hashtbl = kmalloc(size, GFP_KERNEL);
 872         if (!new_hashtbl)
 873                 return -1;
 874
 875         spin_lock_bh(&bond->mode_lock);
 876
 877         bond_info->rx_hashtbl = new_hashtbl;
 878
 879         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 880
 881         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 882                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 883
 884         spin_unlock_bh(&bond->mode_lock);
 885
 886         /* register to receive ARPs */
 887         bond->recv_probe = rlb_arp_recv;
 888
 889         return 0;
 890 }
 891
 892 static void rlb_deinitialize(struct bonding *bond)
 893 {
 894         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 895
 896         spin_lock_bh(&bond->mode_lock);
 897
 898         kfree(bond_info->rx_hashtbl);
 899         bond_info->rx_hashtbl = NULL;
 900         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 901
 902         spin_unlock_bh(&bond->mode_lock);
 903 }
 904
 905 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 906 {
 907         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 908         u32 curr_index;
 909
 910         spin_lock_bh(&bond->mode_lock);
 911
 912         curr_index = bond_info->rx_hashtbl_used_head;
 913         while (curr_index != RLB_NULL_INDEX) {
 914                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 915                 u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 916
 917                 if (curr->vlan_id == vlan_id)
 918                         rlb_delete_table_entry(bond, curr_index);
 919
 920                 curr_index = next_index;
 921         }
 922
 923         spin_unlock_bh(&bond->mode_lock);
 924 }
 925
 926 /*********************** tlb/rlb shared functions *********************/
 927
 928 static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
 929                             __be16 vlan_proto, u16 vid)
 930 {
 931         struct learning_pkt pkt;
 932         struct sk_buff *skb;
 933         int size = sizeof(struct learning_pkt);
 934         char *data;
 935
 936         memset(&pkt, 0, size);
 937         ether_addr_copy(pkt.mac_dst, mac_addr);
 938         ether_addr_copy(pkt.mac_src, mac_addr);
 939         pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
 940
 941         skb = dev_alloc_skb(size);
 942         if (!skb)
 943                 return;
 944
 945         data = skb_put(skb, size);
 946         memcpy(data, &pkt, size);
 947
 948         skb_reset_mac_header(skb);
 949         skb->network_header = skb->mac_header + ETH_HLEN;
 950         skb->protocol = pkt.type;
 951         skb->priority = TC_PRIO_CONTROL;
 952         skb->dev = slave->dev;
 953
 954         if (vid) {
 955                 skb = vlan_put_tag(skb, vlan_proto, vid);
 956                 if (!skb) {
 957                         netdev_err(slave->bond->dev, "failed to insert VLAN tag\n");
 958                         return;
 959                 }
 960         }
 961
 962         dev_queue_xmit(skb);
 963 }
 964
 965 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
 966                                       bool strict_match)
 967 {
 968         struct bonding *bond = bond_get_bond_by_slave(slave);
 969         struct net_device *upper;
 970         struct list_head *iter;
 971         struct bond_vlan_tag *tags;
 972
 973         /* send untagged */
 974         alb_send_lp_vid(slave, mac_addr, 0, 0);
 975
 976         /* loop through all devices and see if we need to send a packet
 977          * for that device.
 978          */
 979         rcu_read_lock();
 980         netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
 981                 if (is_vlan_dev(upper) && vlan_get_encap_level(upper) == 0) {
 982                         if (strict_match &&
 983                             ether_addr_equal_64bits(mac_addr,
 984                                                     upper->dev_addr)) {
 985                                 alb_send_lp_vid(slave, mac_addr,
 986                                                 vlan_dev_vlan_proto(upper),
 987                                                 vlan_dev_vlan_id(upper));
 988                         } else if (!strict_match) {
 989                                 alb_send_lp_vid(slave, upper->dev_addr,
 990                                                 vlan_dev_vlan_proto(upper),
 991                                                 vlan_dev_vlan_id(upper));
 992                         }
 993                 }
 994
 995                 /* If this is a macvlan device, then only send updates
 996                  * when strict_match is turned off.
 997                  */
 998                 if (netif_is_macvlan(upper) && !strict_match) {
 999                         tags = bond_verify_device_path(bond->dev, upper, 0);
1000                         if (IS_ERR_OR_NULL(tags))
1001                                 BUG();
1002                         alb_send_lp_vid(slave, upper->dev_addr,
1003                                         tags[0].vlan_proto, tags[0].vlan_id);
1004                         kfree(tags);
1005                 }
1006         }
1007         rcu_read_unlock();
1008 }
1009
1010 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
1011 {
1012         struct net_device *dev = slave->dev;
1013         struct sockaddr s_addr;
1014
1015         if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1016                 memcpy(dev->dev_addr, addr, dev->addr_len);
1017                 return 0;
1018         }
1019
1020         /* for rlb each slave must have a unique hw mac addresses so that
1021          * each slave will receive packets destined to a different mac
1022          */
1023         memcpy(s_addr.sa_data, addr, dev->addr_len);
1024         s_addr.sa_family = dev->type;
1025         if (dev_set_mac_address(dev, &s_addr)) {
1026                 netdev_err(slave->bond->dev, "dev_set_mac_address of dev %s failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
1027                            dev->name);
1028                 return -EOPNOTSUPP;
1029         }
1030         return 0;
1031 }
1032
1033 /* Swap MAC addresses between two slaves.
1034  *
1035  * Called with RTNL held, and no other locks.
1036  */
1037 static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1038 {
1039         u8 tmp_mac_addr[ETH_ALEN];
1040
1041         ether_addr_copy(tmp_mac_addr, slave1->dev->dev_addr);
1042         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
1043         alb_set_slave_mac_addr(slave2, tmp_mac_addr);
1044
1045 }
1046
1047 /* Send learning packets after MAC address swap.
1048  *
1049  * Called with RTNL and no other locks
1050  */
1051 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1052                                 struct slave *slave2)
1053 {
1054         int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1055         struct slave *disabled_slave = NULL;
1056
1057         ASSERT_RTNL();
1058
1059         /* fasten the change in the switch */
1060         if (bond_slave_can_tx(slave1)) {
1061                 alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1062                 if (bond->alb_info.rlb_enabled) {
1063                         /* inform the clients that the mac address
1064                          * has changed
1065                          */
1066                         rlb_req_update_slave_clients(bond, slave1);
1067                 }
1068         } else {
1069                 disabled_slave = slave1;
1070         }
1071
1072         if (bond_slave_can_tx(slave2)) {
1073                 alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1074                 if (bond->alb_info.rlb_enabled) {
1075                         /* inform the clients that the mac address
1076                          * has changed
1077                          */
1078                         rlb_req_update_slave_clients(bond, slave2);
1079                 }
1080         } else {
1081                 disabled_slave = slave2;
1082         }
1083
1084         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1085                 /* A disabled slave was assigned an active mac addr */
1086                 rlb_teach_disabled_mac_on_primary(bond,
1087                                                   disabled_slave->dev->dev_addr);
1088         }
1089 }
1090
1091 /**
1092  * alb_change_hw_addr_on_detach
1093  * @bond: bonding we're working on
1094  * @slave: the slave that was just detached
1095  *
1096  * We assume that @slave was already detached from the slave list.
1097  *
1098  * If @slave's permanent hw address is different both from its current
1099  * address and from @bond's address, then somewhere in the bond there's
1100  * a slave that has @slave's permanet address as its current address.
1101  * We'll make sure that that slave no longer uses @slave's permanent address.
1102  *
1103  * Caller must hold RTNL and no other locks
1104  */
1105 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1106 {
1107         int perm_curr_diff;
1108         int perm_bond_diff;
1109         struct slave *found_slave;
1110
1111         perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1112                                                   slave->dev->dev_addr);
1113         perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1114                                                   bond->dev->dev_addr);
1115
1116         if (perm_curr_diff && perm_bond_diff) {
1117                 found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1118
1119                 if (found_slave) {
1120                         alb_swap_mac_addr(slave, found_slave);
1121                         alb_fasten_mac_swap(bond, slave, found_slave);
1122                 }
1123         }
1124 }
1125
1126 /**
1127  * alb_handle_addr_collision_on_attach
1128  * @bond: bonding we're working on
1129  * @slave: the slave that was just attached
1130  *
1131  * checks uniqueness of slave's mac address and handles the case the
1132  * new slave uses the bonds mac address.
1133  *
1134  * If the permanent hw address of @slave is @bond's hw address, we need to
1135  * find a different hw address to give @slave, that isn't in use by any other
1136  * slave in the bond. This address must be, of course, one of the permanent
1137  * addresses of the other slaves.
1138  *
1139  * We go over the slave list, and for each slave there we compare its
1140  * permanent hw address with the current address of all the other slaves.
1141  * If no match was found, then we've found a slave with a permanent address
1142  * that isn't used by any other slave in the bond, so we can assign it to
1143  * @slave.
1144  *
1145  * assumption: this function is called before @slave is attached to the
1146  *             bond slave list.
1147  */
1148 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1149 {
1150         struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1151         struct slave *tmp_slave1, *free_mac_slave = NULL;
1152         struct list_head *iter;
1153
1154         if (!bond_has_slaves(bond)) {
1155                 /* this is the first slave */
1156                 return 0;
1157         }
1158
1159         /* if slave's mac address differs from bond's mac address
1160          * check uniqueness of slave's mac address against the other
1161          * slaves in the bond.
1162          */
1163         if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1164                 if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1165                         return 0;
1166
1167                 /* Try setting slave mac to bond address and fall-through
1168                  * to code handling that situation below...
1169                  */
1170                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1171         }
1172
1173         /* The slave's address is equal to the address of the bond.
1174          * Search for a spare address in the bond for this slave.
1175          */
1176         bond_for_each_slave(bond, tmp_slave1, iter) {
1177                 if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1178                         /* no slave has tmp_slave1's perm addr
1179                          * as its curr addr
1180                          */
1181                         free_mac_slave = tmp_slave1;
1182                         break;
1183                 }
1184
1185                 if (!has_bond_addr) {
1186                         if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1187                                                     bond->dev->dev_addr)) {
1188
1189                                 has_bond_addr = tmp_slave1;
1190                         }
1191                 }
1192         }
1193
1194         if (free_mac_slave) {
1195                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1196
1197                 netdev_warn(bond->dev, "the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1198                             slave->dev->name, free_mac_slave->dev->name);
1199
1200         } else if (has_bond_addr) {
1201                 netdev_err(bond->dev, "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",
1202                            slave->dev->name);
1203                 return -EFAULT;
1204         }
1205
1206         return 0;
1207 }
1208
1209 /**
1210  * alb_set_mac_address
1211  * @bond:
1212  * @addr:
1213  *
1214  * In TLB mode all slaves are configured to the bond's hw address, but set
1215  * their dev_addr field to different addresses (based on their permanent hw
1216  * addresses).
1217  *
1218  * For each slave, this function sets the interface to the new address and then
1219  * changes its dev_addr field to its previous value.
1220  *
1221  * Unwinding assumes bond's mac address has not yet changed.
1222  */
1223 static int alb_set_mac_address(struct bonding *bond, void *addr)
1224 {
1225         struct slave *slave, *rollback_slave;
1226         struct list_head *iter;
1227         struct sockaddr sa;
1228         char tmp_addr[ETH_ALEN];
1229         int res;
1230
1231         if (bond->alb_info.rlb_enabled)
1232                 return 0;
1233
1234         bond_for_each_slave(bond, slave, iter) {
1235                 /* save net_device's current hw address */
1236                 ether_addr_copy(tmp_addr, slave->dev->dev_addr);
1237
1238                 res = dev_set_mac_address(slave->dev, addr);
1239
1240                 /* restore net_device's hw address */
1241                 ether_addr_copy(slave->dev->dev_addr, tmp_addr);
1242
1243                 if (res)
1244                         goto unwind;
1245         }
1246
1247         return 0;
1248
1249 unwind:
1250         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1251         sa.sa_family = bond->dev->type;
1252
1253         /* unwind from head to the slave that failed */
1254         bond_for_each_slave(bond, rollback_slave, iter) {
1255                 if (rollback_slave == slave)
1256                         break;
1257                 ether_addr_copy(tmp_addr, rollback_slave->dev->dev_addr);
1258                 dev_set_mac_address(rollback_slave->dev, &sa);
1259                 ether_addr_copy(rollback_slave->dev->dev_addr, tmp_addr);
1260         }
1261
1262         return res;
1263 }
1264
1265 /************************ exported alb funcions ************************/
1266
1267 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1268 {
1269         int res;
1270
1271         res = tlb_initialize(bond);
1272         if (res)
1273                 return res;
1274
1275         if (rlb_enabled) {
1276                 bond->alb_info.rlb_enabled = 1;
1277                 res = rlb_initialize(bond);
1278                 if (res) {
1279                         tlb_deinitialize(bond);
1280                         return res;
1281                 }
1282         } else {
1283                 bond->alb_info.rlb_enabled = 0;
1284         }
1285
1286         return 0;
1287 }
1288
1289 void bond_alb_deinitialize(struct bonding *bond)
1290 {
1291         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1292
1293         tlb_deinitialize(bond);
1294
1295         if (bond_info->rlb_enabled)
1296                 rlb_deinitialize(bond);
1297 }
1298
1299 static int bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1300                             struct slave *tx_slave)
1301 {
1302         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1303         struct ethhdr *eth_data = eth_hdr(skb);
1304
1305         if (!tx_slave) {
1306                 /* unbalanced or unassigned, send through primary */
1307                 tx_slave = rcu_dereference(bond->curr_active_slave);
1308                 if (bond->params.tlb_dynamic_lb)
1309                         bond_info->unbalanced_load += skb->len;
1310         }
1311
1312         if (tx_slave && bond_slave_can_tx(tx_slave)) {
1313                 if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1314                         ether_addr_copy(eth_data->h_source,
1315                                         tx_slave->dev->dev_addr);
1316                 }
1317
1318                 bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1319                 goto out;
1320         }
1321
1322         if (tx_slave && bond->params.tlb_dynamic_lb) {
1323                 spin_lock(&bond->mode_lock);
1324                 __tlb_clear_slave(bond, tx_slave, 0);
1325                 spin_unlock(&bond->mode_lock);
1326         }
1327
1328         /* no suitable interface, frame not sent */
1329         dev_kfree_skb_any(skb);
1330 out:
1331         return NETDEV_TX_OK;
1332 }
1333
1334 int bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1335 {
1336         struct bonding *bond = netdev_priv(bond_dev);
1337         struct ethhdr *eth_data;
1338         struct slave *tx_slave = NULL;
1339         u32 hash_index;
1340
1341         skb_reset_mac_header(skb);
1342         eth_data = eth_hdr(skb);
1343
1344         /* Do not TX balance any multicast or broadcast */
1345         if (!is_multicast_ether_addr(eth_data->h_dest)) {
1346                 switch (skb->protocol) {
1347                 case htons(ETH_P_IP):
1348                 case htons(ETH_P_IPX):
1349                     /* In case of IPX, it will falback to L2 hash */
1350                 case htons(ETH_P_IPV6):
1351                         hash_index = bond_xmit_hash(bond, skb);
1352                         if (bond->params.tlb_dynamic_lb) {
1353                                 tx_slave = tlb_choose_channel(bond,
1354                                                               hash_index & 0xFF,
1355                                                               skb->len);
1356                         } else {
1357                                 struct bond_up_slave *slaves;
1358                                 unsigned int count;
1359
1360                                 slaves = rcu_dereference(bond->slave_arr);
1361                                 count = slaves ? ACCESS_ONCE(slaves->count) : 0;
1362                                 if (likely(count))
1363                                         tx_slave = slaves->arr[hash_index %
1364                                                                count];
1365                         }
1366                         break;
1367                 }
1368         }
1369         return bond_do_alb_xmit(skb, bond, tx_slave);
1370 }
1371
1372 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1373 {
1374         struct bonding *bond = netdev_priv(bond_dev);
1375         struct ethhdr *eth_data;
1376         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1377         struct slave *tx_slave = NULL;
1378         static const __be32 ip_bcast = htonl(0xffffffff);
1379         int hash_size = 0;
1380         bool do_tx_balance = true;
1381         u32 hash_index = 0;
1382         const u8 *hash_start = NULL;
1383         struct ipv6hdr *ip6hdr;
1384
1385         skb_reset_mac_header(skb);
1386         eth_data = eth_hdr(skb);
1387
1388         switch (ntohs(skb->protocol)) {
1389         case ETH_P_IP: {
1390                 const struct iphdr *iph = ip_hdr(skb);
1391
1392                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast) ||
1393                     (iph->daddr == ip_bcast) ||
1394                     (iph->protocol == IPPROTO_IGMP)) {
1395                         do_tx_balance = false;
1396                         break;
1397                 }
1398                 hash_start = (char *)&(iph->daddr);
1399                 hash_size = sizeof(iph->daddr);
1400         }
1401                 break;
1402         case ETH_P_IPV6:
1403                 /* IPv6 doesn't really use broadcast mac address, but leave
1404                  * that here just in case.
1405                  */
1406                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast)) {
1407                         do_tx_balance = false;
1408                         break;
1409                 }
1410
1411                 /* IPv6 uses all-nodes multicast as an equivalent to
1412                  * broadcasts in IPv4.
1413                  */
1414                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1415                         do_tx_balance = false;
1416                         break;
1417                 }
1418
1419                 /* Additianally, DAD probes should not be tx-balanced as that
1420                  * will lead to false positives for duplicate addresses and
1421                  * prevent address configuration from working.
1422                  */
1423                 ip6hdr = ipv6_hdr(skb);
1424                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1425                         do_tx_balance = false;
1426                         break;
1427                 }
1428
1429                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1430                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1431                 break;
1432         case ETH_P_IPX:
1433                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1434                         /* something is wrong with this packet */
1435                         do_tx_balance = false;
1436                         break;
1437                 }
1438
1439                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1440                         /* The only protocol worth balancing in
1441                          * this family since it has an "ARP" like
1442                          * mechanism
1443                          */
1444                         do_tx_balance = false;
1445                         break;
1446                 }
1447
1448                 hash_start = (char *)eth_data->h_dest;
1449                 hash_size = ETH_ALEN;
1450                 break;
1451         case ETH_P_ARP:
1452                 do_tx_balance = false;
1453                 if (bond_info->rlb_enabled)
1454                         tx_slave = rlb_arp_xmit(skb, bond);
1455                 break;
1456         default:
1457                 do_tx_balance = false;
1458                 break;
1459         }
1460
1461         if (do_tx_balance) {
1462                 hash_index = _simple_hash(hash_start, hash_size);
1463                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1464         }
1465
1466         return bond_do_alb_xmit(skb, bond, tx_slave);
1467 }
1468
1469 void bond_alb_monitor(struct work_struct *work)
1470 {
1471         struct bonding *bond = container_of(work, struct bonding,
1472                                             alb_work.work);
1473         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1474         struct list_head *iter;
1475         struct slave *slave;
1476
1477         if (!bond_has_slaves(bond)) {
1478                 bond_info->tx_rebalance_counter = 0;
1479                 bond_info->lp_counter = 0;
1480                 goto re_arm;
1481         }
1482
1483         rcu_read_lock();
1484
1485         bond_info->tx_rebalance_counter++;
1486         bond_info->lp_counter++;
1487
1488         /* send learning packets */
1489         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1490                 bool strict_match;
1491
1492                 bond_for_each_slave_rcu(bond, slave, iter) {
1493                         /* If updating current_active, use all currently
1494                          * user mac addreses (!strict_match).  Otherwise, only
1495                          * use mac of the slave device.
1496                          * In RLB mode, we always use strict matches.
1497                          */
1498                         strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1499                                         bond_info->rlb_enabled);
1500                         alb_send_learning_packets(slave, slave->dev->dev_addr,
1501                                                   strict_match);
1502                 }
1503                 bond_info->lp_counter = 0;
1504         }
1505
1506         /* rebalance tx traffic */
1507         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1508                 bond_for_each_slave_rcu(bond, slave, iter) {
1509                         tlb_clear_slave(bond, slave, 1);
1510                         if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1511                                 SLAVE_TLB_INFO(slave).load =
1512                                         bond_info->unbalanced_load /
1513                                                 BOND_TLB_REBALANCE_INTERVAL;
1514                                 bond_info->unbalanced_load = 0;
1515                         }
1516                 }
1517                 bond_info->tx_rebalance_counter = 0;
1518         }
1519
1520         if (bond_info->rlb_enabled) {
1521                 if (bond_info->primary_is_promisc &&
1522                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1523
1524                         /* dev_set_promiscuity requires rtnl and
1525                          * nothing else.  Avoid race with bond_close.
1526                          */
1527                         rcu_read_unlock();
1528                         if (!rtnl_trylock())
1529                                 goto re_arm;
1530
1531                         bond_info->rlb_promisc_timeout_counter = 0;
1532
1533                         /* If the primary was set to promiscuous mode
1534                          * because a slave was disabled then
1535                          * it can now leave promiscuous mode.
1536                          */
1537                         dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1538                                             -1);
1539                         bond_info->primary_is_promisc = 0;
1540
1541                         rtnl_unlock();
1542                         rcu_read_lock();
1543                 }
1544
1545                 if (bond_info->rlb_rebalance) {
1546                         bond_info->rlb_rebalance = 0;
1547                         rlb_rebalance(bond);
1548                 }
1549
1550                 /* check if clients need updating */
1551                 if (bond_info->rx_ntt) {
1552                         if (bond_info->rlb_update_delay_counter) {
1553                                 --bond_info->rlb_update_delay_counter;
1554                         } else {
1555                                 rlb_update_rx_clients(bond);
1556                                 if (bond_info->rlb_update_retry_counter)
1557                                         --bond_info->rlb_update_retry_counter;
1558                                 else
1559                                         bond_info->rx_ntt = 0;
1560                         }
1561                 }
1562         }
1563         rcu_read_unlock();
1564 re_arm:
1565         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1566 }
1567
1568 /* assumption: called before the slave is attached to the bond
1569  * and not locked by the bond lock
1570  */
1571 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1572 {
1573         int res;
1574
1575         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1576         if (res)
1577                 return res;
1578
1579         res = alb_handle_addr_collision_on_attach(bond, slave);
1580         if (res)
1581                 return res;
1582
1583         tlb_init_slave(slave);
1584
1585         /* order a rebalance ASAP */
1586         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1587
1588         if (bond->alb_info.rlb_enabled)
1589                 bond->alb_info.rlb_rebalance = 1;
1590
1591         return 0;
1592 }
1593
1594 /* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1595  * if necessary.
1596  *
1597  * Caller must hold RTNL and no other locks
1598  */
1599 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1600 {
1601         if (bond_has_slaves(bond))
1602                 alb_change_hw_addr_on_detach(bond, slave);
1603
1604         tlb_clear_slave(bond, slave, 0);
1605
1606         if (bond->alb_info.rlb_enabled) {
1607                 bond->alb_info.rx_slave = NULL;
1608                 rlb_clear_slave(bond, slave);
1609         }
1610
1611 }
1612
1613 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1614 {
1615         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1616
1617         if (link == BOND_LINK_DOWN) {
1618                 tlb_clear_slave(bond, slave, 0);
1619                 if (bond->alb_info.rlb_enabled)
1620                         rlb_clear_slave(bond, slave);
1621         } else if (link == BOND_LINK_UP) {
1622                 /* order a rebalance ASAP */
1623                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1624                 if (bond->alb_info.rlb_enabled) {
1625                         bond->alb_info.rlb_rebalance = 1;
1626                         /* If the updelay module parameter is smaller than the
1627                          * forwarding delay of the switch the rebalance will
1628                          * not work because the rebalance arp replies will
1629                          * not be forwarded to the clients..
1630                          */
1631                 }
1632         }
1633
1634         if (bond_is_nondyn_tlb(bond)) {
1635                 if (bond_update_slave_arr(bond, NULL))
1636                         pr_err("Failed to build slave-array for TLB mode.\n");
1637         }
1638 }
1639
1640 /**
1641  * bond_alb_handle_active_change - assign new curr_active_slave
1642  * @bond: our bonding struct
1643  * @new_slave: new slave to assign
1644  *
1645  * Set the bond->curr_active_slave to @new_slave and handle
1646  * mac address swapping and promiscuity changes as needed.
1647  *
1648  * Caller must hold RTNL
1649  */
1650 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1651 {
1652         struct slave *swap_slave;
1653         struct slave *curr_active;
1654
1655         curr_active = rtnl_dereference(bond->curr_active_slave);
1656         if (curr_active == new_slave)
1657                 return;
1658
1659         if (curr_active && bond->alb_info.primary_is_promisc) {
1660                 dev_set_promiscuity(curr_active->dev, -1);
1661                 bond->alb_info.primary_is_promisc = 0;
1662                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1663         }
1664
1665         swap_slave = curr_active;
1666         rcu_assign_pointer(bond->curr_active_slave, new_slave);
1667
1668         if (!new_slave || !bond_has_slaves(bond))
1669                 return;
1670
1671         /* set the new curr_active_slave to the bonds mac address
1672          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1673          */
1674         if (!swap_slave)
1675                 swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1676
1677         /* Arrange for swap_slave and new_slave to temporarily be
1678          * ignored so we can mess with their MAC addresses without
1679          * fear of interference from transmit activity.
1680          */
1681         if (swap_slave)
1682                 tlb_clear_slave(bond, swap_slave, 1);
1683         tlb_clear_slave(bond, new_slave, 1);
1684
1685         /* in TLB mode, the slave might flip down/up with the old dev_addr,
1686          * and thus filter bond->dev_addr's packets, so force bond's mac
1687          */
1688         if (BOND_MODE(bond) == BOND_MODE_TLB) {
1689                 struct sockaddr sa;
1690                 u8 tmp_addr[ETH_ALEN];
1691
1692                 ether_addr_copy(tmp_addr, new_slave->dev->dev_addr);
1693
1694                 memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1695                 sa.sa_family = bond->dev->type;
1696                 /* we don't care if it can't change its mac, best effort */
1697                 dev_set_mac_address(new_slave->dev, &sa);
1698
1699                 ether_addr_copy(new_slave->dev->dev_addr, tmp_addr);
1700         }
1701
1702         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1703         if (swap_slave) {
1704                 /* swap mac address */
1705                 alb_swap_mac_addr(swap_slave, new_slave);
1706                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1707         } else {
1708                 /* set the new_slave to the bond mac address */
1709                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1710                 alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1711                                           false);
1712         }
1713 }
1714
1715 /* Called with RTNL */
1716 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1717 {
1718         struct bonding *bond = netdev_priv(bond_dev);
1719         struct sockaddr *sa = addr;
1720         struct slave *curr_active;
1721         struct slave *swap_slave;
1722         int res;
1723
1724         if (!is_valid_ether_addr(sa->sa_data))
1725                 return -EADDRNOTAVAIL;
1726
1727         res = alb_set_mac_address(bond, addr);
1728         if (res)
1729                 return res;
1730
1731         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1732
1733         /* If there is no curr_active_slave there is nothing else to do.
1734          * Otherwise we'll need to pass the new address to it and handle
1735          * duplications.
1736          */
1737         curr_active = rtnl_dereference(bond->curr_active_slave);
1738         if (!curr_active)
1739                 return 0;
1740
1741         swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1742
1743         if (swap_slave) {
1744                 alb_swap_mac_addr(swap_slave, curr_active);
1745                 alb_fasten_mac_swap(bond, swap_slave, curr_active);
1746         } else {
1747                 alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr);
1748
1749                 alb_send_learning_packets(curr_active,
1750                                           bond_dev->dev_addr, false);
1751                 if (bond->alb_info.rlb_enabled) {
1752                         /* inform clients mac address has changed */
1753                         rlb_req_update_slave_clients(bond, curr_active);
1754                 }
1755         }
1756
1757         return 0;
1758 }
1759
1760 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1761 {
1762         if (bond->alb_info.rlb_enabled)
1763                 rlb_clear_vlan(bond, vlan_id);
1764 }
1765