kernel/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 <net/bonding.h>
  41 #include <net/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                         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 479                                                client_info->vlan_id);
 480                 }
 481
 482                 arp_xmit(skb);
 483         }
 484 }
 485
 486 /* sends ARP REPLIES that update the clients that need updating */
 487 static void rlb_update_rx_clients(struct bonding *bond)
 488 {
 489         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 490         struct rlb_client_info *client_info;
 491         u32 hash_index;
 492
 493         spin_lock_bh(&bond->mode_lock);
 494
 495         hash_index = bond_info->rx_hashtbl_used_head;
 496         for (; hash_index != RLB_NULL_INDEX;
 497              hash_index = client_info->used_next) {
 498                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 499                 if (client_info->ntt) {
 500                         rlb_update_client(client_info);
 501                         if (bond_info->rlb_update_retry_counter == 0)
 502                                 client_info->ntt = 0;
 503                 }
 504         }
 505
 506         /* do not update the entries again until this counter is zero so that
 507          * not to confuse the clients.
 508          */
 509         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 510
 511         spin_unlock_bh(&bond->mode_lock);
 512 }
 513
 514 /* The slave was assigned a new mac address - update the clients */
 515 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 516 {
 517         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 518         struct rlb_client_info *client_info;
 519         int ntt = 0;
 520         u32 hash_index;
 521
 522         spin_lock_bh(&bond->mode_lock);
 523
 524         hash_index = bond_info->rx_hashtbl_used_head;
 525         for (; hash_index != RLB_NULL_INDEX;
 526              hash_index = client_info->used_next) {
 527                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 528
 529                 if ((client_info->slave == slave) &&
 530                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 531                         client_info->ntt = 1;
 532                         ntt = 1;
 533                 }
 534         }
 535
 536         /* update the team's flag only after the whole iteration */
 537         if (ntt) {
 538                 bond_info->rx_ntt = 1;
 539                 /* fasten the change */
 540                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 541         }
 542
 543         spin_unlock_bh(&bond->mode_lock);
 544 }
 545
 546 /* mark all clients using src_ip to be updated */
 547 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 548 {
 549         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 550         struct rlb_client_info *client_info;
 551         u32 hash_index;
 552
 553         spin_lock(&bond->mode_lock);
 554
 555         hash_index = bond_info->rx_hashtbl_used_head;
 556         for (; hash_index != RLB_NULL_INDEX;
 557              hash_index = client_info->used_next) {
 558                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 559
 560                 if (!client_info->slave) {
 561                         netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
 562                         continue;
 563                 }
 564                 /* update all clients using this src_ip, that are not assigned
 565                  * to the team's address (curr_active_slave) and have a known
 566                  * unicast mac address.
 567                  */
 568                 if ((client_info->ip_src == src_ip) &&
 569                     !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 570                                              bond->dev->dev_addr) &&
 571                     !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 572                         client_info->ntt = 1;
 573                         bond_info->rx_ntt = 1;
 574                 }
 575         }
 576
 577         spin_unlock(&bond->mode_lock);
 578 }
 579
 580 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 581 {
 582         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 583         struct arp_pkt *arp = arp_pkt(skb);
 584         struct slave *assigned_slave, *curr_active_slave;
 585         struct rlb_client_info *client_info;
 586         u32 hash_index = 0;
 587
 588         spin_lock(&bond->mode_lock);
 589
 590         curr_active_slave = rcu_dereference(bond->curr_active_slave);
 591
 592         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 593         client_info = &(bond_info->rx_hashtbl[hash_index]);
 594
 595         if (client_info->assigned) {
 596                 if ((client_info->ip_src == arp->ip_src) &&
 597                     (client_info->ip_dst == arp->ip_dst)) {
 598                         /* the entry is already assigned to this client */
 599                         if (!ether_addr_equal_64bits(arp->mac_dst, mac_bcast)) {
 600                                 /* update mac address from arp */
 601                                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 602                         }
 603                         ether_addr_copy(client_info->mac_src, arp->mac_src);
 604
 605                         assigned_slave = client_info->slave;
 606                         if (assigned_slave) {
 607                                 spin_unlock(&bond->mode_lock);
 608                                 return assigned_slave;
 609                         }
 610                 } else {
 611                         /* the entry is already assigned to some other client,
 612                          * move the old client to primary (curr_active_slave) so
 613                          * that the new client can be assigned to this entry.
 614                          */
 615                         if (curr_active_slave &&
 616                             client_info->slave != curr_active_slave) {
 617                                 client_info->slave = curr_active_slave;
 618                                 rlb_update_client(client_info);
 619                         }
 620                 }
 621         }
 622         /* assign a new slave */
 623         assigned_slave = __rlb_next_rx_slave(bond);
 624
 625         if (assigned_slave) {
 626                 if (!(client_info->assigned &&
 627                       client_info->ip_src == arp->ip_src)) {
 628                         /* ip_src is going to be updated,
 629                          * fix the src hash list
 630                          */
 631                         u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 632                                                     sizeof(arp->ip_src));
 633                         rlb_src_unlink(bond, hash_index);
 634                         rlb_src_link(bond, hash_src, hash_index);
 635                 }
 636
 637                 client_info->ip_src = arp->ip_src;
 638                 client_info->ip_dst = arp->ip_dst;
 639                 /* arp->mac_dst is broadcast for arp reqeusts.
 640                  * will be updated with clients actual unicast mac address
 641                  * upon receiving an arp reply.
 642                  */
 643                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 644                 ether_addr_copy(client_info->mac_src, arp->mac_src);
 645                 client_info->slave = assigned_slave;
 646
 647                 if (!ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 648                         client_info->ntt = 1;
 649                         bond->alb_info.rx_ntt = 1;
 650                 } else {
 651                         client_info->ntt = 0;
 652                 }
 653
 654                 if (vlan_get_tag(skb, &client_info->vlan_id))
 655                         client_info->vlan_id = 0;
 656
 657                 if (!client_info->assigned) {
 658                         u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 659                         bond_info->rx_hashtbl_used_head = hash_index;
 660                         client_info->used_next = prev_tbl_head;
 661                         if (prev_tbl_head != RLB_NULL_INDEX) {
 662                                 bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 663                                         hash_index;
 664                         }
 665                         client_info->assigned = 1;
 666                 }
 667         }
 668
 669         spin_unlock(&bond->mode_lock);
 670
 671         return assigned_slave;
 672 }
 673
 674 /* chooses (and returns) transmit channel for arp reply
 675  * does not choose channel for other arp types since they are
 676  * sent on the curr_active_slave
 677  */
 678 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 679 {
 680         struct arp_pkt *arp = arp_pkt(skb);
 681         struct slave *tx_slave = NULL;
 682
 683         /* Don't modify or load balance ARPs that do not originate locally
 684          * (e.g.,arrive via a bridge).
 685          */
 686         if (!bond_slave_has_mac_rx(bond, arp->mac_src))
 687                 return NULL;
 688
 689         if (arp->op_code == htons(ARPOP_REPLY)) {
 690                 /* the arp must be sent on the selected rx channel */
 691                 tx_slave = rlb_choose_channel(skb, bond);
 692                 if (tx_slave)
 693                         ether_addr_copy(arp->mac_src, tx_slave->dev->dev_addr);
 694                 netdev_dbg(bond->dev, "Server sent ARP Reply packet\n");
 695         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 696                 /* Create an entry in the rx_hashtbl for this client as a
 697                  * place holder.
 698                  * When the arp reply is received the entry will be updated
 699                  * with the correct unicast address of the client.
 700                  */
 701                 rlb_choose_channel(skb, bond);
 702
 703                 /* The ARP reply packets must be delayed so that
 704                  * they can cancel out the influence of the ARP request.
 705                  */
 706                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 707
 708                 /* arp requests are broadcast and are sent on the primary
 709                  * the arp request will collapse all clients on the subnet to
 710                  * the primary slave. We must register these clients to be
 711                  * updated with their assigned mac.
 712                  */
 713                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 714                 netdev_dbg(bond->dev, "Server sent ARP Request packet\n");
 715         }
 716
 717         return tx_slave;
 718 }
 719
 720 static void rlb_rebalance(struct bonding *bond)
 721 {
 722         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 723         struct slave *assigned_slave;
 724         struct rlb_client_info *client_info;
 725         int ntt;
 726         u32 hash_index;
 727
 728         spin_lock_bh(&bond->mode_lock);
 729
 730         ntt = 0;
 731         hash_index = bond_info->rx_hashtbl_used_head;
 732         for (; hash_index != RLB_NULL_INDEX;
 733              hash_index = client_info->used_next) {
 734                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 735                 assigned_slave = __rlb_next_rx_slave(bond);
 736                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 737                         client_info->slave = assigned_slave;
 738                         client_info->ntt = 1;
 739                         ntt = 1;
 740                 }
 741         }
 742
 743         /* update the team's flag only after the whole iteration */
 744         if (ntt)
 745                 bond_info->rx_ntt = 1;
 746         spin_unlock_bh(&bond->mode_lock);
 747 }
 748
 749 /* Caller must hold mode_lock */
 750 static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 751 {
 752         entry->used_next = RLB_NULL_INDEX;
 753         entry->used_prev = RLB_NULL_INDEX;
 754         entry->assigned = 0;
 755         entry->slave = NULL;
 756         entry->vlan_id = 0;
 757 }
 758 static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 759 {
 760         entry->src_first = RLB_NULL_INDEX;
 761         entry->src_prev = RLB_NULL_INDEX;
 762         entry->src_next = RLB_NULL_INDEX;
 763 }
 764
 765 static void rlb_init_table_entry(struct rlb_client_info *entry)
 766 {
 767         memset(entry, 0, sizeof(struct rlb_client_info));
 768         rlb_init_table_entry_dst(entry);
 769         rlb_init_table_entry_src(entry);
 770 }
 771
 772 static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 773 {
 774         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 775         u32 next_index = bond_info->rx_hashtbl[index].used_next;
 776         u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 777
 778         if (index == bond_info->rx_hashtbl_used_head)
 779                 bond_info->rx_hashtbl_used_head = next_index;
 780         if (prev_index != RLB_NULL_INDEX)
 781                 bond_info->rx_hashtbl[prev_index].used_next = next_index;
 782         if (next_index != RLB_NULL_INDEX)
 783                 bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 784 }
 785
 786 /* unlink a rlb hash table entry from the src list */
 787 static void rlb_src_unlink(struct bonding *bond, u32 index)
 788 {
 789         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 790         u32 next_index = bond_info->rx_hashtbl[index].src_next;
 791         u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 792
 793         bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 794         bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 795
 796         if (next_index != RLB_NULL_INDEX)
 797                 bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 798
 799         if (prev_index == RLB_NULL_INDEX)
 800                 return;
 801
 802         /* is prev_index pointing to the head of this list? */
 803         if (bond_info->rx_hashtbl[prev_index].src_first == index)
 804                 bond_info->rx_hashtbl[prev_index].src_first = next_index;
 805         else
 806                 bond_info->rx_hashtbl[prev_index].src_next = next_index;
 807
 808 }
 809
 810 static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 811 {
 812         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 813         struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 814
 815         rlb_delete_table_entry_dst(bond, index);
 816         rlb_init_table_entry_dst(entry);
 817
 818         rlb_src_unlink(bond, index);
 819 }
 820
 821 /* add the rx_hashtbl[ip_dst_hash] entry to the list
 822  * of entries with identical ip_src_hash
 823  */
 824 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 825 {
 826         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 827         u32 next;
 828
 829         bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 830         next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 831         bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 832         if (next != RLB_NULL_INDEX)
 833                 bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 834         bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 835 }
 836
 837 /* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
 838  * not match arp->mac_src
 839  */
 840 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 841 {
 842         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 843         u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 844         u32 index;
 845
 846         spin_lock_bh(&bond->mode_lock);
 847
 848         index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 849         while (index != RLB_NULL_INDEX) {
 850                 struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 851                 u32 next_index = entry->src_next;
 852                 if (entry->ip_src == arp->ip_src &&
 853                     !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 854                                 rlb_delete_table_entry(bond, index);
 855                 index = next_index;
 856         }
 857         spin_unlock_bh(&bond->mode_lock);
 858 }
 859
 860 static int rlb_initialize(struct bonding *bond)
 861 {
 862         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 863         struct rlb_client_info  *new_hashtbl;
 864         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 865         int i;
 866
 867         new_hashtbl = kmalloc(size, GFP_KERNEL);
 868         if (!new_hashtbl)
 869                 return -1;
 870
 871         spin_lock_bh(&bond->mode_lock);
 872
 873         bond_info->rx_hashtbl = new_hashtbl;
 874
 875         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 876
 877         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 878                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 879
 880         spin_unlock_bh(&bond->mode_lock);
 881
 882         /* register to receive ARPs */
 883         bond->recv_probe = rlb_arp_recv;
 884
 885         return 0;
 886 }
 887
 888 static void rlb_deinitialize(struct bonding *bond)
 889 {
 890         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 891
 892         spin_lock_bh(&bond->mode_lock);
 893
 894         kfree(bond_info->rx_hashtbl);
 895         bond_info->rx_hashtbl = NULL;
 896         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 897
 898         spin_unlock_bh(&bond->mode_lock);
 899 }
 900
 901 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 902 {
 903         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 904         u32 curr_index;
 905
 906         spin_lock_bh(&bond->mode_lock);
 907
 908         curr_index = bond_info->rx_hashtbl_used_head;
 909         while (curr_index != RLB_NULL_INDEX) {
 910                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 911                 u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 912
 913                 if (curr->vlan_id == vlan_id)
 914                         rlb_delete_table_entry(bond, curr_index);
 915
 916                 curr_index = next_index;
 917         }
 918
 919         spin_unlock_bh(&bond->mode_lock);
 920 }
 921
 922 /*********************** tlb/rlb shared functions *********************/
 923
 924 static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
 925                             __be16 vlan_proto, u16 vid)
 926 {
 927         struct learning_pkt pkt;
 928         struct sk_buff *skb;
 929         int size = sizeof(struct learning_pkt);
 930         char *data;
 931
 932         memset(&pkt, 0, size);
 933         ether_addr_copy(pkt.mac_dst, mac_addr);
 934         ether_addr_copy(pkt.mac_src, mac_addr);
 935         pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
 936
 937         skb = dev_alloc_skb(size);
 938         if (!skb)
 939                 return;
 940
 941         data = skb_put(skb, size);
 942         memcpy(data, &pkt, size);
 943
 944         skb_reset_mac_header(skb);
 945         skb->network_header = skb->mac_header + ETH_HLEN;
 946         skb->protocol = pkt.type;
 947         skb->priority = TC_PRIO_CONTROL;
 948         skb->dev = slave->dev;
 949
 950         if (vid)
 951                 __vlan_hwaccel_put_tag(skb, vlan_proto, vid);
 952
 953         dev_queue_xmit(skb);
 954 }
 955
 956 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
 957                                       bool strict_match)
 958 {
 959         struct bonding *bond = bond_get_bond_by_slave(slave);
 960         struct net_device *upper;
 961         struct list_head *iter;
 962         struct bond_vlan_tag *tags;
 963
 964         /* send untagged */
 965         alb_send_lp_vid(slave, mac_addr, 0, 0);
 966
 967         /* loop through all devices and see if we need to send a packet
 968          * for that device.
 969          */
 970         rcu_read_lock();
 971         netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
 972                 if (is_vlan_dev(upper) && vlan_get_encap_level(upper) == 0) {
 973                         if (strict_match &&
 974                             ether_addr_equal_64bits(mac_addr,
 975                                                     upper->dev_addr)) {
 976                                 alb_send_lp_vid(slave, mac_addr,
 977                                                 vlan_dev_vlan_proto(upper),
 978                                                 vlan_dev_vlan_id(upper));
 979                         } else if (!strict_match) {
 980                                 alb_send_lp_vid(slave, upper->dev_addr,
 981                                                 vlan_dev_vlan_proto(upper),
 982                                                 vlan_dev_vlan_id(upper));
 983                         }
 984                 }
 985
 986                 /* If this is a macvlan device, then only send updates
 987                  * when strict_match is turned off.
 988                  */
 989                 if (netif_is_macvlan(upper) && !strict_match) {
 990                         tags = bond_verify_device_path(bond->dev, upper, 0);
 991                         if (IS_ERR_OR_NULL(tags))
 992                                 BUG();
 993                         alb_send_lp_vid(slave, upper->dev_addr,
 994                                         tags[0].vlan_proto, tags[0].vlan_id);
 995                         kfree(tags);
 996                 }
 997         }
 998         rcu_read_unlock();
 999 }
1000
1001 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
1002 {
1003         struct net_device *dev = slave->dev;
1004         struct sockaddr s_addr;
1005
1006         if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1007                 memcpy(dev->dev_addr, addr, dev->addr_len);
1008                 return 0;
1009         }
1010
1011         /* for rlb each slave must have a unique hw mac addresses so that
1012          * each slave will receive packets destined to a different mac
1013          */
1014         memcpy(s_addr.sa_data, addr, dev->addr_len);
1015         s_addr.sa_family = dev->type;
1016         if (dev_set_mac_address(dev, &s_addr)) {
1017                 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",
1018                            dev->name);
1019                 return -EOPNOTSUPP;
1020         }
1021         return 0;
1022 }
1023
1024 /* Swap MAC addresses between two slaves.
1025  *
1026  * Called with RTNL held, and no other locks.
1027  */
1028 static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1029 {
1030         u8 tmp_mac_addr[ETH_ALEN];
1031
1032         ether_addr_copy(tmp_mac_addr, slave1->dev->dev_addr);
1033         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
1034         alb_set_slave_mac_addr(slave2, tmp_mac_addr);
1035
1036 }
1037
1038 /* Send learning packets after MAC address swap.
1039  *
1040  * Called with RTNL and no other locks
1041  */
1042 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1043                                 struct slave *slave2)
1044 {
1045         int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1046         struct slave *disabled_slave = NULL;
1047
1048         ASSERT_RTNL();
1049
1050         /* fasten the change in the switch */
1051         if (bond_slave_can_tx(slave1)) {
1052                 alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1053                 if (bond->alb_info.rlb_enabled) {
1054                         /* inform the clients that the mac address
1055                          * has changed
1056                          */
1057                         rlb_req_update_slave_clients(bond, slave1);
1058                 }
1059         } else {
1060                 disabled_slave = slave1;
1061         }
1062
1063         if (bond_slave_can_tx(slave2)) {
1064                 alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1065                 if (bond->alb_info.rlb_enabled) {
1066                         /* inform the clients that the mac address
1067                          * has changed
1068                          */
1069                         rlb_req_update_slave_clients(bond, slave2);
1070                 }
1071         } else {
1072                 disabled_slave = slave2;
1073         }
1074
1075         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1076                 /* A disabled slave was assigned an active mac addr */
1077                 rlb_teach_disabled_mac_on_primary(bond,
1078                                                   disabled_slave->dev->dev_addr);
1079         }
1080 }
1081
1082 /**
1083  * alb_change_hw_addr_on_detach
1084  * @bond: bonding we're working on
1085  * @slave: the slave that was just detached
1086  *
1087  * We assume that @slave was already detached from the slave list.
1088  *
1089  * If @slave's permanent hw address is different both from its current
1090  * address and from @bond's address, then somewhere in the bond there's
1091  * a slave that has @slave's permanet address as its current address.
1092  * We'll make sure that that slave no longer uses @slave's permanent address.
1093  *
1094  * Caller must hold RTNL and no other locks
1095  */
1096 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1097 {
1098         int perm_curr_diff;
1099         int perm_bond_diff;
1100         struct slave *found_slave;
1101
1102         perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1103                                                   slave->dev->dev_addr);
1104         perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1105                                                   bond->dev->dev_addr);
1106
1107         if (perm_curr_diff && perm_bond_diff) {
1108                 found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1109
1110                 if (found_slave) {
1111                         alb_swap_mac_addr(slave, found_slave);
1112                         alb_fasten_mac_swap(bond, slave, found_slave);
1113                 }
1114         }
1115 }
1116
1117 /**
1118  * alb_handle_addr_collision_on_attach
1119  * @bond: bonding we're working on
1120  * @slave: the slave that was just attached
1121  *
1122  * checks uniqueness of slave's mac address and handles the case the
1123  * new slave uses the bonds mac address.
1124  *
1125  * If the permanent hw address of @slave is @bond's hw address, we need to
1126  * find a different hw address to give @slave, that isn't in use by any other
1127  * slave in the bond. This address must be, of course, one of the permanent
1128  * addresses of the other slaves.
1129  *
1130  * We go over the slave list, and for each slave there we compare its
1131  * permanent hw address with the current address of all the other slaves.
1132  * If no match was found, then we've found a slave with a permanent address
1133  * that isn't used by any other slave in the bond, so we can assign it to
1134  * @slave.
1135  *
1136  * assumption: this function is called before @slave is attached to the
1137  *             bond slave list.
1138  */
1139 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1140 {
1141         struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1142         struct slave *tmp_slave1, *free_mac_slave = NULL;
1143         struct list_head *iter;
1144
1145         if (!bond_has_slaves(bond)) {
1146                 /* this is the first slave */
1147                 return 0;
1148         }
1149
1150         /* if slave's mac address differs from bond's mac address
1151          * check uniqueness of slave's mac address against the other
1152          * slaves in the bond.
1153          */
1154         if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1155                 if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1156                         return 0;
1157
1158                 /* Try setting slave mac to bond address and fall-through
1159                  * to code handling that situation below...
1160                  */
1161                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1162         }
1163
1164         /* The slave's address is equal to the address of the bond.
1165          * Search for a spare address in the bond for this slave.
1166          */
1167         bond_for_each_slave(bond, tmp_slave1, iter) {
1168                 if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1169                         /* no slave has tmp_slave1's perm addr
1170                          * as its curr addr
1171                          */
1172                         free_mac_slave = tmp_slave1;
1173                         break;
1174                 }
1175
1176                 if (!has_bond_addr) {
1177                         if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1178                                                     bond->dev->dev_addr)) {
1179
1180                                 has_bond_addr = tmp_slave1;
1181                         }
1182                 }
1183         }
1184
1185         if (free_mac_slave) {
1186                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1187
1188                 netdev_warn(bond->dev, "the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1189                             slave->dev->name, free_mac_slave->dev->name);
1190
1191         } else if (has_bond_addr) {
1192                 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",
1193                            slave->dev->name);
1194                 return -EFAULT;
1195         }
1196
1197         return 0;
1198 }
1199
1200 /**
1201  * alb_set_mac_address
1202  * @bond:
1203  * @addr:
1204  *
1205  * In TLB mode all slaves are configured to the bond's hw address, but set
1206  * their dev_addr field to different addresses (based on their permanent hw
1207  * addresses).
1208  *
1209  * For each slave, this function sets the interface to the new address and then
1210  * changes its dev_addr field to its previous value.
1211  *
1212  * Unwinding assumes bond's mac address has not yet changed.
1213  */
1214 static int alb_set_mac_address(struct bonding *bond, void *addr)
1215 {
1216         struct slave *slave, *rollback_slave;
1217         struct list_head *iter;
1218         struct sockaddr sa;
1219         char tmp_addr[ETH_ALEN];
1220         int res;
1221
1222         if (bond->alb_info.rlb_enabled)
1223                 return 0;
1224
1225         bond_for_each_slave(bond, slave, iter) {
1226                 /* save net_device's current hw address */
1227                 ether_addr_copy(tmp_addr, slave->dev->dev_addr);
1228
1229                 res = dev_set_mac_address(slave->dev, addr);
1230
1231                 /* restore net_device's hw address */
1232                 ether_addr_copy(slave->dev->dev_addr, tmp_addr);
1233
1234                 if (res)
1235                         goto unwind;
1236         }
1237
1238         return 0;
1239
1240 unwind:
1241         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1242         sa.sa_family = bond->dev->type;
1243
1244         /* unwind from head to the slave that failed */
1245         bond_for_each_slave(bond, rollback_slave, iter) {
1246                 if (rollback_slave == slave)
1247                         break;
1248                 ether_addr_copy(tmp_addr, rollback_slave->dev->dev_addr);
1249                 dev_set_mac_address(rollback_slave->dev, &sa);
1250                 ether_addr_copy(rollback_slave->dev->dev_addr, tmp_addr);
1251         }
1252
1253         return res;
1254 }
1255
1256 /************************ exported alb funcions ************************/
1257
1258 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1259 {
1260         int res;
1261
1262         res = tlb_initialize(bond);
1263         if (res)
1264                 return res;
1265
1266         if (rlb_enabled) {
1267                 bond->alb_info.rlb_enabled = 1;
1268                 res = rlb_initialize(bond);
1269                 if (res) {
1270                         tlb_deinitialize(bond);
1271                         return res;
1272                 }
1273         } else {
1274                 bond->alb_info.rlb_enabled = 0;
1275         }
1276
1277         return 0;
1278 }
1279
1280 void bond_alb_deinitialize(struct bonding *bond)
1281 {
1282         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1283
1284         tlb_deinitialize(bond);
1285
1286         if (bond_info->rlb_enabled)
1287                 rlb_deinitialize(bond);
1288 }
1289
1290 static int bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1291                             struct slave *tx_slave)
1292 {
1293         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1294         struct ethhdr *eth_data = eth_hdr(skb);
1295
1296         if (!tx_slave) {
1297                 /* unbalanced or unassigned, send through primary */
1298                 tx_slave = rcu_dereference(bond->curr_active_slave);
1299                 if (bond->params.tlb_dynamic_lb)
1300                         bond_info->unbalanced_load += skb->len;
1301         }
1302
1303         if (tx_slave && bond_slave_can_tx(tx_slave)) {
1304                 if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1305                         ether_addr_copy(eth_data->h_source,
1306                                         tx_slave->dev->dev_addr);
1307                 }
1308
1309                 bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1310                 goto out;
1311         }
1312
1313         if (tx_slave && bond->params.tlb_dynamic_lb) {
1314                 spin_lock(&bond->mode_lock);
1315                 __tlb_clear_slave(bond, tx_slave, 0);
1316                 spin_unlock(&bond->mode_lock);
1317         }
1318
1319         /* no suitable interface, frame not sent */
1320         bond_tx_drop(bond->dev, skb);
1321 out:
1322         return NETDEV_TX_OK;
1323 }
1324
1325 int bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1326 {
1327         struct bonding *bond = netdev_priv(bond_dev);
1328         struct ethhdr *eth_data;
1329         struct slave *tx_slave = NULL;
1330         u32 hash_index;
1331
1332         skb_reset_mac_header(skb);
1333         eth_data = eth_hdr(skb);
1334
1335         /* Do not TX balance any multicast or broadcast */
1336         if (!is_multicast_ether_addr(eth_data->h_dest)) {
1337                 switch (skb->protocol) {
1338                 case htons(ETH_P_IP):
1339                 case htons(ETH_P_IPX):
1340                     /* In case of IPX, it will falback to L2 hash */
1341                 case htons(ETH_P_IPV6):
1342                         hash_index = bond_xmit_hash(bond, skb);
1343                         if (bond->params.tlb_dynamic_lb) {
1344                                 tx_slave = tlb_choose_channel(bond,
1345                                                               hash_index & 0xFF,
1346                                                               skb->len);
1347                         } else {
1348                                 struct bond_up_slave *slaves;
1349                                 unsigned int count;
1350
1351                                 slaves = rcu_dereference(bond->slave_arr);
1352                                 count = slaves ? ACCESS_ONCE(slaves->count) : 0;
1353                                 if (likely(count))
1354                                         tx_slave = slaves->arr[hash_index %
1355                                                                count];
1356                         }
1357                         break;
1358                 }
1359         }
1360         return bond_do_alb_xmit(skb, bond, tx_slave);
1361 }
1362
1363 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1364 {
1365         struct bonding *bond = netdev_priv(bond_dev);
1366         struct ethhdr *eth_data;
1367         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1368         struct slave *tx_slave = NULL;
1369         static const __be32 ip_bcast = htonl(0xffffffff);
1370         int hash_size = 0;
1371         bool do_tx_balance = true;
1372         u32 hash_index = 0;
1373         const u8 *hash_start = NULL;
1374         struct ipv6hdr *ip6hdr;
1375
1376         skb_reset_mac_header(skb);
1377         eth_data = eth_hdr(skb);
1378
1379         switch (ntohs(skb->protocol)) {
1380         case ETH_P_IP: {
1381                 const struct iphdr *iph = ip_hdr(skb);
1382
1383                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast) ||
1384                     (iph->daddr == ip_bcast) ||
1385                     (iph->protocol == IPPROTO_IGMP)) {
1386                         do_tx_balance = false;
1387                         break;
1388                 }
1389                 hash_start = (char *)&(iph->daddr);
1390                 hash_size = sizeof(iph->daddr);
1391         }
1392                 break;
1393         case ETH_P_IPV6:
1394                 /* IPv6 doesn't really use broadcast mac address, but leave
1395                  * that here just in case.
1396                  */
1397                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast)) {
1398                         do_tx_balance = false;
1399                         break;
1400                 }
1401
1402                 /* IPv6 uses all-nodes multicast as an equivalent to
1403                  * broadcasts in IPv4.
1404                  */
1405                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1406                         do_tx_balance = false;
1407                         break;
1408                 }
1409
1410                 /* Additianally, DAD probes should not be tx-balanced as that
1411                  * will lead to false positives for duplicate addresses and
1412                  * prevent address configuration from working.
1413                  */
1414                 ip6hdr = ipv6_hdr(skb);
1415                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1416                         do_tx_balance = false;
1417                         break;
1418                 }
1419
1420                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1421                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1422                 break;
1423         case ETH_P_IPX:
1424                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1425                         /* something is wrong with this packet */
1426                         do_tx_balance = false;
1427                         break;
1428                 }
1429
1430                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1431                         /* The only protocol worth balancing in
1432                          * this family since it has an "ARP" like
1433                          * mechanism
1434                          */
1435                         do_tx_balance = false;
1436                         break;
1437                 }
1438
1439                 hash_start = (char *)eth_data->h_dest;
1440                 hash_size = ETH_ALEN;
1441                 break;
1442         case ETH_P_ARP:
1443                 do_tx_balance = false;
1444                 if (bond_info->rlb_enabled)
1445                         tx_slave = rlb_arp_xmit(skb, bond);
1446                 break;
1447         default:
1448                 do_tx_balance = false;
1449                 break;
1450         }
1451
1452         if (do_tx_balance) {
1453                 hash_index = _simple_hash(hash_start, hash_size);
1454                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1455         }
1456
1457         return bond_do_alb_xmit(skb, bond, tx_slave);
1458 }
1459
1460 void bond_alb_monitor(struct work_struct *work)
1461 {
1462         struct bonding *bond = container_of(work, struct bonding,
1463                                             alb_work.work);
1464         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1465         struct list_head *iter;
1466         struct slave *slave;
1467
1468         if (!bond_has_slaves(bond)) {
1469                 bond_info->tx_rebalance_counter = 0;
1470                 bond_info->lp_counter = 0;
1471                 goto re_arm;
1472         }
1473
1474         rcu_read_lock();
1475
1476         bond_info->tx_rebalance_counter++;
1477         bond_info->lp_counter++;
1478
1479         /* send learning packets */
1480         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1481                 bool strict_match;
1482
1483                 bond_for_each_slave_rcu(bond, slave, iter) {
1484                         /* If updating current_active, use all currently
1485                          * user mac addreses (!strict_match).  Otherwise, only
1486                          * use mac of the slave device.
1487                          * In RLB mode, we always use strict matches.
1488                          */
1489                         strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1490                                         bond_info->rlb_enabled);
1491                         alb_send_learning_packets(slave, slave->dev->dev_addr,
1492                                                   strict_match);
1493                 }
1494                 bond_info->lp_counter = 0;
1495         }
1496
1497         /* rebalance tx traffic */
1498         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1499                 bond_for_each_slave_rcu(bond, slave, iter) {
1500                         tlb_clear_slave(bond, slave, 1);
1501                         if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1502                                 SLAVE_TLB_INFO(slave).load =
1503                                         bond_info->unbalanced_load /
1504                                                 BOND_TLB_REBALANCE_INTERVAL;
1505                                 bond_info->unbalanced_load = 0;
1506                         }
1507                 }
1508                 bond_info->tx_rebalance_counter = 0;
1509         }
1510
1511         if (bond_info->rlb_enabled) {
1512                 if (bond_info->primary_is_promisc &&
1513                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1514
1515                         /* dev_set_promiscuity requires rtnl and
1516                          * nothing else.  Avoid race with bond_close.
1517                          */
1518                         rcu_read_unlock();
1519                         if (!rtnl_trylock())
1520                                 goto re_arm;
1521
1522                         bond_info->rlb_promisc_timeout_counter = 0;
1523
1524                         /* If the primary was set to promiscuous mode
1525                          * because a slave was disabled then
1526                          * it can now leave promiscuous mode.
1527                          */
1528                         dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1529                                             -1);
1530                         bond_info->primary_is_promisc = 0;
1531
1532                         rtnl_unlock();
1533                         rcu_read_lock();
1534                 }
1535
1536                 if (bond_info->rlb_rebalance) {
1537                         bond_info->rlb_rebalance = 0;
1538                         rlb_rebalance(bond);
1539                 }
1540
1541                 /* check if clients need updating */
1542                 if (bond_info->rx_ntt) {
1543                         if (bond_info->rlb_update_delay_counter) {
1544                                 --bond_info->rlb_update_delay_counter;
1545                         } else {
1546                                 rlb_update_rx_clients(bond);
1547                                 if (bond_info->rlb_update_retry_counter)
1548                                         --bond_info->rlb_update_retry_counter;
1549                                 else
1550                                         bond_info->rx_ntt = 0;
1551                         }
1552                 }
1553         }
1554         rcu_read_unlock();
1555 re_arm:
1556         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1557 }
1558
1559 /* assumption: called before the slave is attached to the bond
1560  * and not locked by the bond lock
1561  */
1562 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1563 {
1564         int res;
1565
1566         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1567         if (res)
1568                 return res;
1569
1570         res = alb_handle_addr_collision_on_attach(bond, slave);
1571         if (res)
1572                 return res;
1573
1574         tlb_init_slave(slave);
1575
1576         /* order a rebalance ASAP */
1577         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1578
1579         if (bond->alb_info.rlb_enabled)
1580                 bond->alb_info.rlb_rebalance = 1;
1581
1582         return 0;
1583 }
1584
1585 /* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1586  * if necessary.
1587  *
1588  * Caller must hold RTNL and no other locks
1589  */
1590 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1591 {
1592         if (bond_has_slaves(bond))
1593                 alb_change_hw_addr_on_detach(bond, slave);
1594
1595         tlb_clear_slave(bond, slave, 0);
1596
1597         if (bond->alb_info.rlb_enabled) {
1598                 bond->alb_info.rx_slave = NULL;
1599                 rlb_clear_slave(bond, slave);
1600         }
1601
1602 }
1603
1604 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1605 {
1606         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1607
1608         if (link == BOND_LINK_DOWN) {
1609                 tlb_clear_slave(bond, slave, 0);
1610                 if (bond->alb_info.rlb_enabled)
1611                         rlb_clear_slave(bond, slave);
1612         } else if (link == BOND_LINK_UP) {
1613                 /* order a rebalance ASAP */
1614                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1615                 if (bond->alb_info.rlb_enabled) {
1616                         bond->alb_info.rlb_rebalance = 1;
1617                         /* If the updelay module parameter is smaller than the
1618                          * forwarding delay of the switch the rebalance will
1619                          * not work because the rebalance arp replies will
1620                          * not be forwarded to the clients..
1621                          */
1622                 }
1623         }
1624
1625         if (bond_is_nondyn_tlb(bond)) {
1626                 if (bond_update_slave_arr(bond, NULL))
1627                         pr_err("Failed to build slave-array for TLB mode.\n");
1628         }
1629 }
1630
1631 /**
1632  * bond_alb_handle_active_change - assign new curr_active_slave
1633  * @bond: our bonding struct
1634  * @new_slave: new slave to assign
1635  *
1636  * Set the bond->curr_active_slave to @new_slave and handle
1637  * mac address swapping and promiscuity changes as needed.
1638  *
1639  * Caller must hold RTNL
1640  */
1641 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1642 {
1643         struct slave *swap_slave;
1644         struct slave *curr_active;
1645
1646         curr_active = rtnl_dereference(bond->curr_active_slave);
1647         if (curr_active == new_slave)
1648                 return;
1649
1650         if (curr_active && bond->alb_info.primary_is_promisc) {
1651                 dev_set_promiscuity(curr_active->dev, -1);
1652                 bond->alb_info.primary_is_promisc = 0;
1653                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1654         }
1655
1656         swap_slave = curr_active;
1657         rcu_assign_pointer(bond->curr_active_slave, new_slave);
1658
1659         if (!new_slave || !bond_has_slaves(bond))
1660                 return;
1661
1662         /* set the new curr_active_slave to the bonds mac address
1663          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1664          */
1665         if (!swap_slave)
1666                 swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1667
1668         /* Arrange for swap_slave and new_slave to temporarily be
1669          * ignored so we can mess with their MAC addresses without
1670          * fear of interference from transmit activity.
1671          */
1672         if (swap_slave)
1673                 tlb_clear_slave(bond, swap_slave, 1);
1674         tlb_clear_slave(bond, new_slave, 1);
1675
1676         /* in TLB mode, the slave might flip down/up with the old dev_addr,
1677          * and thus filter bond->dev_addr's packets, so force bond's mac
1678          */
1679         if (BOND_MODE(bond) == BOND_MODE_TLB) {
1680                 struct sockaddr sa;
1681                 u8 tmp_addr[ETH_ALEN];
1682
1683                 ether_addr_copy(tmp_addr, new_slave->dev->dev_addr);
1684
1685                 memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1686                 sa.sa_family = bond->dev->type;
1687                 /* we don't care if it can't change its mac, best effort */
1688                 dev_set_mac_address(new_slave->dev, &sa);
1689
1690                 ether_addr_copy(new_slave->dev->dev_addr, tmp_addr);
1691         }
1692
1693         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1694         if (swap_slave) {
1695                 /* swap mac address */
1696                 alb_swap_mac_addr(swap_slave, new_slave);
1697                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1698         } else {
1699                 /* set the new_slave to the bond mac address */
1700                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1701                 alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1702                                           false);
1703         }
1704 }
1705
1706 /* Called with RTNL */
1707 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1708 {
1709         struct bonding *bond = netdev_priv(bond_dev);
1710         struct sockaddr *sa = addr;
1711         struct slave *curr_active;
1712         struct slave *swap_slave;
1713         int res;
1714
1715         if (!is_valid_ether_addr(sa->sa_data))
1716                 return -EADDRNOTAVAIL;
1717
1718         res = alb_set_mac_address(bond, addr);
1719         if (res)
1720                 return res;
1721
1722         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1723
1724         /* If there is no curr_active_slave there is nothing else to do.
1725          * Otherwise we'll need to pass the new address to it and handle
1726          * duplications.
1727          */
1728         curr_active = rtnl_dereference(bond->curr_active_slave);
1729         if (!curr_active)
1730                 return 0;
1731
1732         swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1733
1734         if (swap_slave) {
1735                 alb_swap_mac_addr(swap_slave, curr_active);
1736                 alb_fasten_mac_swap(bond, swap_slave, curr_active);
1737         } else {
1738                 alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr);
1739
1740                 alb_send_learning_packets(curr_active,
1741                                           bond_dev->dev_addr, false);
1742                 if (bond->alb_info.rlb_enabled) {
1743                         /* inform clients mac address has changed */
1744                         rlb_req_update_slave_clients(bond, curr_active);
1745                 }
1746         }
1747
1748         return 0;
1749 }
1750
1751 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1752 {
1753         if (bond->alb_info.rlb_enabled)
1754                 rlb_clear_vlan(bond, vlan_id);
1755 }
1756