drivers/net/bonding/bond

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
_simple_hash
tlb_init_table_entry
tlb_init_slave
__tlb_clear_slave
tlb_clear_slave
tlb_initialize
tlb_deinitialize
compute_gap
tlb_get_least_loaded_slave
__tlb_choose_channel
tlb_choose_channel
rlb_update_entry_from_arp
rlb_arp_recv
__rlb_next_rx_slave
rlb_next_rx_slave
rlb_teach_disabled_mac_on_primary
rlb_clear_slave
rlb_update_client
rlb_update_rx_clients
rlb_req_update_slave_clients
rlb_req_update_subnet_clients
rlb_choose_channel
rlb_arp_xmit
rlb_rebalance
rlb_init_table_entry_dst
rlb_init_table_entry_src
rlb_init_table_entry
rlb_delete_table_entry_dst
rlb_src_unlink
rlb_delete_table_entry
rlb_src_link
rlb_purge_src_ip
rlb_initialize
rlb_deinitialize
rlb_clear_vlan
alb_send_lp_vid
alb_upper_dev_walk
alb_send_learning_packets
alb_set_slave_mac_addr
alb_swap_mac_addr
alb_fasten_mac_swap
alb_change_hw_addr_on_detach
alb_handle_addr_collision_on_attach
alb_set_mac_address
bond_alb_initialize
bond_alb_deinitialize
bond_do_alb_xmit
bond_tlb_xmit
bond_alb_xmit
bond_alb_monitor
bond_alb_init_slave
bond_alb_deinit_slave
bond_alb_handle_link_change
bond_alb_handle_active_change
bond_alb_set_mac_address
bond_alb_clear_vlan
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
   4  */
   5 
   6 #include <linux/skbuff.h>
   7 #include <linux/netdevice.h>
   8 #include <linux/etherdevice.h>
   9 #include <linux/pkt_sched.h>
  10 #include <linux/spinlock.h>
  11 #include <linux/slab.h>
  12 #include <linux/timer.h>
  13 #include <linux/ip.h>
  14 #include <linux/ipv6.h>
  15 #include <linux/if_arp.h>
  16 #include <linux/if_ether.h>
  17 #include <linux/if_bonding.h>
  18 #include <linux/if_vlan.h>
  19 #include <linux/in.h>
  20 #include <net/ipx.h>
  21 #include <net/arp.h>
  22 #include <net/ipv6.h>
  23 #include <asm/byteorder.h>
  24 #include <net/bonding.h>
  25 #include <net/bond_alb.h>
  26 
  27 static const u8 mac_v6_allmcast[ETH_ALEN + 2] __long_aligned = {
  28         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  29 };
  30 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  31 
  32 #pragma pack(1)
  33 struct learning_pkt {
  34         u8 mac_dst[ETH_ALEN];
  35         u8 mac_src[ETH_ALEN];
  36         __be16 type;
  37         u8 padding[ETH_ZLEN - ETH_HLEN];
  38 };
  39 
  40 struct arp_pkt {
  41         __be16  hw_addr_space;
  42         __be16  prot_addr_space;
  43         u8      hw_addr_len;
  44         u8      prot_addr_len;
  45         __be16  op_code;
  46         u8      mac_src[ETH_ALEN];      /* sender hardware address */
  47         __be32  ip_src;                 /* sender IP address */
  48         u8      mac_dst[ETH_ALEN];      /* target hardware address */
  49         __be32  ip_dst;                 /* target IP address */
  50 };
  51 #pragma pack()
  52 
  53 /* Forward declaration */
  54 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
  55                                       bool strict_match);
  56 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  57 static void rlb_src_unlink(struct bonding *bond, u32 index);
  58 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  59                          u32 ip_dst_hash);
  60 
  61 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  62 {
  63         int i;
  64         u8 hash = 0;
  65 
  66         for (i = 0; i < hash_size; i++)
  67                 hash ^= hash_start[i];
  68 
  69         return hash;
  70 }
  71 
  72 /*********************** tlb specific functions ***************************/
  73 
  74 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
  75 {
  76         if (save_load) {
  77                 entry->load_history = 1 + entry->tx_bytes /
  78                                       BOND_TLB_REBALANCE_INTERVAL;
  79                 entry->tx_bytes = 0;
  80         }
  81 
  82         entry->tx_slave = NULL;
  83         entry->next = TLB_NULL_INDEX;
  84         entry->prev = TLB_NULL_INDEX;
  85 }
  86 
  87 static inline void tlb_init_slave(struct slave *slave)
  88 {
  89         SLAVE_TLB_INFO(slave).load = 0;
  90         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
  91 }
  92 
  93 static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
  94                          int save_load)
  95 {
  96         struct tlb_client_info *tx_hash_table;
  97         u32 index;
  98 
  99         /* clear slave from tx_hashtbl */
 100         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 101 
 102         /* skip this if we've already freed the tx hash table */
 103         if (tx_hash_table) {
 104                 index = SLAVE_TLB_INFO(slave).head;
 105                 while (index != TLB_NULL_INDEX) {
 106                         u32 next_index = tx_hash_table[index].next;
 107                         tlb_init_table_entry(&tx_hash_table[index], save_load);
 108                         index = next_index;
 109                 }
 110         }
 111 
 112         tlb_init_slave(slave);
 113 }
 114 
 115 static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 116                          int save_load)
 117 {
 118         spin_lock_bh(&bond->mode_lock);
 119         __tlb_clear_slave(bond, slave, save_load);
 120         spin_unlock_bh(&bond->mode_lock);
 121 }
 122 
 123 /* Must be called before starting the monitor timer */
 124 static int tlb_initialize(struct bonding *bond)
 125 {
 126         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 127         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 128         struct tlb_client_info *new_hashtbl;
 129         int i;
 130 
 131         new_hashtbl = kzalloc(size, GFP_KERNEL);
 132         if (!new_hashtbl)
 133                 return -ENOMEM;
 134 
 135         spin_lock_bh(&bond->mode_lock);
 136 
 137         bond_info->tx_hashtbl = new_hashtbl;
 138 
 139         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
 140                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 141 
 142         spin_unlock_bh(&bond->mode_lock);
 143 
 144         return 0;
 145 }
 146 
 147 /* Must be called only after all slaves have been released */
 148 static void tlb_deinitialize(struct bonding *bond)
 149 {
 150         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 151 
 152         spin_lock_bh(&bond->mode_lock);
 153 
 154         kfree(bond_info->tx_hashtbl);
 155         bond_info->tx_hashtbl = NULL;
 156 
 157         spin_unlock_bh(&bond->mode_lock);
 158 }
 159 
 160 static long long compute_gap(struct slave *slave)
 161 {
 162         return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 163                (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 164 }
 165 
 166 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 167 {
 168         struct slave *slave, *least_loaded;
 169         struct list_head *iter;
 170         long long max_gap;
 171 
 172         least_loaded = NULL;
 173         max_gap = LLONG_MIN;
 174 
 175         /* Find the slave with the largest gap */
 176         bond_for_each_slave_rcu(bond, slave, iter) {
 177                 if (bond_slave_can_tx(slave)) {
 178                         long long gap = compute_gap(slave);
 179 
 180                         if (max_gap < gap) {
 181                                 least_loaded = slave;
 182                                 max_gap = gap;
 183                         }
 184                 }
 185         }
 186 
 187         return least_loaded;
 188 }
 189 
 190 static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 191                                                 u32 skb_len)
 192 {
 193         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 194         struct tlb_client_info *hash_table;
 195         struct slave *assigned_slave;
 196 
 197         hash_table = bond_info->tx_hashtbl;
 198         assigned_slave = hash_table[hash_index].tx_slave;
 199         if (!assigned_slave) {
 200                 assigned_slave = tlb_get_least_loaded_slave(bond);
 201 
 202                 if (assigned_slave) {
 203                         struct tlb_slave_info *slave_info =
 204                                 &(SLAVE_TLB_INFO(assigned_slave));
 205                         u32 next_index = slave_info->head;
 206 
 207                         hash_table[hash_index].tx_slave = assigned_slave;
 208                         hash_table[hash_index].next = next_index;
 209                         hash_table[hash_index].prev = TLB_NULL_INDEX;
 210 
 211                         if (next_index != TLB_NULL_INDEX)
 212                                 hash_table[next_index].prev = hash_index;
 213 
 214                         slave_info->head = hash_index;
 215                         slave_info->load +=
 216                                 hash_table[hash_index].load_history;
 217                 }
 218         }
 219 
 220         if (assigned_slave)
 221                 hash_table[hash_index].tx_bytes += skb_len;
 222 
 223         return assigned_slave;
 224 }
 225 
 226 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 227                                         u32 skb_len)
 228 {
 229         struct slave *tx_slave;
 230 
 231         /* We don't need to disable softirq here, becase
 232          * tlb_choose_channel() is only called by bond_alb_xmit()
 233          * which already has softirq disabled.
 234          */
 235         spin_lock(&bond->mode_lock);
 236         tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 237         spin_unlock(&bond->mode_lock);
 238 
 239         return tx_slave;
 240 }
 241 
 242 /*********************** rlb specific functions ***************************/
 243 
 244 /* when an ARP REPLY is received from a client update its info
 245  * in the rx_hashtbl
 246  */
 247 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 248 {
 249         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 250         struct rlb_client_info *client_info;
 251         u32 hash_index;
 252 
 253         spin_lock_bh(&bond->mode_lock);
 254 
 255         hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 256         client_info = &(bond_info->rx_hashtbl[hash_index]);
 257 
 258         if ((client_info->assigned) &&
 259             (client_info->ip_src == arp->ip_dst) &&
 260             (client_info->ip_dst == arp->ip_src) &&
 261             (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
 262                 /* update the clients MAC address */
 263                 ether_addr_copy(client_info->mac_dst, arp->mac_src);
 264                 client_info->ntt = 1;
 265                 bond_info->rx_ntt = 1;
 266         }
 267 
 268         spin_unlock_bh(&bond->mode_lock);
 269 }
 270 
 271 static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
 272                         struct slave *slave)
 273 {
 274         struct arp_pkt *arp, _arp;
 275 
 276         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 277                 goto out;
 278 
 279         arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
 280         if (!arp)
 281                 goto out;
 282 
 283         /* We received an ARP from arp->ip_src.
 284          * We might have used this IP address previously (on the bonding host
 285          * itself or on a system that is bridged together with the bond).
 286          * However, if arp->mac_src is different than what is stored in
 287          * rx_hashtbl, some other host is now using the IP and we must prevent
 288          * sending out client updates with this IP address and the old MAC
 289          * address.
 290          * Clean up all hash table entries that have this address as ip_src but
 291          * have a different mac_src.
 292          */
 293         rlb_purge_src_ip(bond, arp);
 294 
 295         if (arp->op_code == htons(ARPOP_REPLY)) {
 296                 /* update rx hash table for this ARP */
 297                 rlb_update_entry_from_arp(bond, arp);
 298                 slave_dbg(bond->dev, slave->dev, "Server received an ARP Reply from client\n");
 299         }
 300 out:
 301         return RX_HANDLER_ANOTHER;
 302 }
 303 
 304 /* Caller must hold rcu_read_lock() */
 305 static struct slave *__rlb_next_rx_slave(struct bonding *bond)
 306 {
 307         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 308         struct slave *before = NULL, *rx_slave = NULL, *slave;
 309         struct list_head *iter;
 310         bool found = false;
 311 
 312         bond_for_each_slave_rcu(bond, slave, iter) {
 313                 if (!bond_slave_can_tx(slave))
 314                         continue;
 315                 if (!found) {
 316                         if (!before || before->speed < slave->speed)
 317                                 before = slave;
 318                 } else {
 319                         if (!rx_slave || rx_slave->speed < slave->speed)
 320                                 rx_slave = slave;
 321                 }
 322                 if (slave == bond_info->rx_slave)
 323                         found = true;
 324         }
 325         /* we didn't find anything after the current or we have something
 326          * better before and up to the current slave
 327          */
 328         if (!rx_slave || (before && rx_slave->speed < before->speed))
 329                 rx_slave = before;
 330 
 331         if (rx_slave)
 332                 bond_info->rx_slave = rx_slave;
 333 
 334         return rx_slave;
 335 }
 336 
 337 /* Caller must hold RTNL, rcu_read_lock is obtained only to silence checkers */
 338 static struct slave *rlb_next_rx_slave(struct bonding *bond)
 339 {
 340         struct slave *rx_slave;
 341 
 342         ASSERT_RTNL();
 343 
 344         rcu_read_lock();
 345         rx_slave = __rlb_next_rx_slave(bond);
 346         rcu_read_unlock();
 347 
 348         return rx_slave;
 349 }
 350 
 351 /* teach the switch the mac of a disabled slave
 352  * on the primary for fault tolerance
 353  *
 354  * Caller must hold RTNL
 355  */
 356 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 357 {
 358         struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
 359 
 360         if (!curr_active)
 361                 return;
 362 
 363         if (!bond->alb_info.primary_is_promisc) {
 364                 if (!dev_set_promiscuity(curr_active->dev, 1))
 365                         bond->alb_info.primary_is_promisc = 1;
 366                 else
 367                         bond->alb_info.primary_is_promisc = 0;
 368         }
 369 
 370         bond->alb_info.rlb_promisc_timeout_counter = 0;
 371 
 372         alb_send_learning_packets(curr_active, addr, true);
 373 }
 374 
 375 /* slave being removed should not be active at this point
 376  *
 377  * Caller must hold rtnl.
 378  */
 379 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 380 {
 381         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 382         struct rlb_client_info *rx_hash_table;
 383         u32 index, next_index;
 384 
 385         /* clear slave from rx_hashtbl */
 386         spin_lock_bh(&bond->mode_lock);
 387 
 388         rx_hash_table = bond_info->rx_hashtbl;
 389         index = bond_info->rx_hashtbl_used_head;
 390         for (; index != RLB_NULL_INDEX; index = next_index) {
 391                 next_index = rx_hash_table[index].used_next;
 392                 if (rx_hash_table[index].slave == slave) {
 393                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
 394 
 395                         if (assigned_slave) {
 396                                 rx_hash_table[index].slave = assigned_slave;
 397                                 if (is_valid_ether_addr(rx_hash_table[index].mac_dst)) {
 398                                         bond_info->rx_hashtbl[index].ntt = 1;
 399                                         bond_info->rx_ntt = 1;
 400                                         /* A slave has been removed from the
 401                                          * table because it is either disabled
 402                                          * or being released. We must retry the
 403                                          * update to avoid clients from not
 404                                          * being updated & disconnecting when
 405                                          * there is stress
 406                                          */
 407                                         bond_info->rlb_update_retry_counter =
 408                                                 RLB_UPDATE_RETRY;
 409                                 }
 410                         } else {  /* there is no active slave */
 411                                 rx_hash_table[index].slave = NULL;
 412                         }
 413                 }
 414         }
 415 
 416         spin_unlock_bh(&bond->mode_lock);
 417 
 418         if (slave != rtnl_dereference(bond->curr_active_slave))
 419                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 420 }
 421 
 422 static void rlb_update_client(struct rlb_client_info *client_info)
 423 {
 424         int i;
 425 
 426         if (!client_info->slave || !is_valid_ether_addr(client_info->mac_dst))
 427                 return;
 428 
 429         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 430                 struct sk_buff *skb;
 431 
 432                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 433                                  client_info->ip_dst,
 434                                  client_info->slave->dev,
 435                                  client_info->ip_src,
 436                                  client_info->mac_dst,
 437                                  client_info->slave->dev->dev_addr,
 438                                  client_info->mac_dst);
 439                 if (!skb) {
 440                         slave_err(client_info->slave->bond->dev,
 441                                   client_info->slave->dev,
 442                                   "failed to create an ARP packet\n");
 443                         continue;
 444                 }
 445 
 446                 skb->dev = client_info->slave->dev;
 447 
 448                 if (client_info->vlan_id) {
 449                         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 450                                                client_info->vlan_id);
 451                 }
 452 
 453                 arp_xmit(skb);
 454         }
 455 }
 456 
 457 /* sends ARP REPLIES that update the clients that need updating */
 458 static void rlb_update_rx_clients(struct bonding *bond)
 459 {
 460         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 461         struct rlb_client_info *client_info;
 462         u32 hash_index;
 463 
 464         spin_lock_bh(&bond->mode_lock);
 465 
 466         hash_index = bond_info->rx_hashtbl_used_head;
 467         for (; hash_index != RLB_NULL_INDEX;
 468              hash_index = client_info->used_next) {
 469                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 470                 if (client_info->ntt) {
 471                         rlb_update_client(client_info);
 472                         if (bond_info->rlb_update_retry_counter == 0)
 473                                 client_info->ntt = 0;
 474                 }
 475         }
 476 
 477         /* do not update the entries again until this counter is zero so that
 478          * not to confuse the clients.
 479          */
 480         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 481 
 482         spin_unlock_bh(&bond->mode_lock);
 483 }
 484 
 485 /* The slave was assigned a new mac address - update the clients */
 486 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 487 {
 488         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 489         struct rlb_client_info *client_info;
 490         int ntt = 0;
 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 
 500                 if ((client_info->slave == slave) &&
 501                     is_valid_ether_addr(client_info->mac_dst)) {
 502                         client_info->ntt = 1;
 503                         ntt = 1;
 504                 }
 505         }
 506 
 507         /* update the team's flag only after the whole iteration */
 508         if (ntt) {
 509                 bond_info->rx_ntt = 1;
 510                 /* fasten the change */
 511                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 512         }
 513 
 514         spin_unlock_bh(&bond->mode_lock);
 515 }
 516 
 517 /* mark all clients using src_ip to be updated */
 518 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 519 {
 520         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 521         struct rlb_client_info *client_info;
 522         u32 hash_index;
 523 
 524         spin_lock(&bond->mode_lock);
 525 
 526         hash_index = bond_info->rx_hashtbl_used_head;
 527         for (; hash_index != RLB_NULL_INDEX;
 528              hash_index = client_info->used_next) {
 529                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 530 
 531                 if (!client_info->slave) {
 532                         netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
 533                         continue;
 534                 }
 535                 /* update all clients using this src_ip, that are not assigned
 536                  * to the team's address (curr_active_slave) and have a known
 537                  * unicast mac address.
 538                  */
 539                 if ((client_info->ip_src == src_ip) &&
 540                     !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 541                                              bond->dev->dev_addr) &&
 542                     is_valid_ether_addr(client_info->mac_dst)) {
 543                         client_info->ntt = 1;
 544                         bond_info->rx_ntt = 1;
 545                 }
 546         }
 547 
 548         spin_unlock(&bond->mode_lock);
 549 }
 550 
 551 static struct slave *rlb_choose_channel(struct sk_buff *skb,
 552                                         struct bonding *bond,
 553                                         const struct arp_pkt *arp)
 554 {
 555         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 556         struct slave *assigned_slave, *curr_active_slave;
 557         struct rlb_client_info *client_info;
 558         u32 hash_index = 0;
 559 
 560         spin_lock(&bond->mode_lock);
 561 
 562         curr_active_slave = rcu_dereference(bond->curr_active_slave);
 563 
 564         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 565         client_info = &(bond_info->rx_hashtbl[hash_index]);
 566 
 567         if (client_info->assigned) {
 568                 if ((client_info->ip_src == arp->ip_src) &&
 569                     (client_info->ip_dst == arp->ip_dst)) {
 570                         /* the entry is already assigned to this client */
 571                         if (!is_broadcast_ether_addr(arp->mac_dst)) {
 572                                 /* update mac address from arp */
 573                                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 574                         }
 575                         ether_addr_copy(client_info->mac_src, arp->mac_src);
 576 
 577                         assigned_slave = client_info->slave;
 578                         if (assigned_slave) {
 579                                 spin_unlock(&bond->mode_lock);
 580                                 return assigned_slave;
 581                         }
 582                 } else {
 583                         /* the entry is already assigned to some other client,
 584                          * move the old client to primary (curr_active_slave) so
 585                          * that the new client can be assigned to this entry.
 586                          */
 587                         if (curr_active_slave &&
 588                             client_info->slave != curr_active_slave) {
 589                                 client_info->slave = curr_active_slave;
 590                                 rlb_update_client(client_info);
 591                         }
 592                 }
 593         }
 594         /* assign a new slave */
 595         assigned_slave = __rlb_next_rx_slave(bond);
 596 
 597         if (assigned_slave) {
 598                 if (!(client_info->assigned &&
 599                       client_info->ip_src == arp->ip_src)) {
 600                         /* ip_src is going to be updated,
 601                          * fix the src hash list
 602                          */
 603                         u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 604                                                     sizeof(arp->ip_src));
 605                         rlb_src_unlink(bond, hash_index);
 606                         rlb_src_link(bond, hash_src, hash_index);
 607                 }
 608 
 609                 client_info->ip_src = arp->ip_src;
 610                 client_info->ip_dst = arp->ip_dst;
 611                 /* arp->mac_dst is broadcast for arp reqeusts.
 612                  * will be updated with clients actual unicast mac address
 613                  * upon receiving an arp reply.
 614                  */
 615                 ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 616                 ether_addr_copy(client_info->mac_src, arp->mac_src);
 617                 client_info->slave = assigned_slave;
 618 
 619                 if (is_valid_ether_addr(client_info->mac_dst)) {
 620                         client_info->ntt = 1;
 621                         bond->alb_info.rx_ntt = 1;
 622                 } else {
 623                         client_info->ntt = 0;
 624                 }
 625 
 626                 if (vlan_get_tag(skb, &client_info->vlan_id))
 627                         client_info->vlan_id = 0;
 628 
 629                 if (!client_info->assigned) {
 630                         u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 631                         bond_info->rx_hashtbl_used_head = hash_index;
 632                         client_info->used_next = prev_tbl_head;
 633                         if (prev_tbl_head != RLB_NULL_INDEX) {
 634                                 bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 635                                         hash_index;
 636                         }
 637                         client_info->assigned = 1;
 638                 }
 639         }
 640 
 641         spin_unlock(&bond->mode_lock);
 642 
 643         return assigned_slave;
 644 }
 645 
 646 /* chooses (and returns) transmit channel for arp reply
 647  * does not choose channel for other arp types since they are
 648  * sent on the curr_active_slave
 649  */
 650 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 651 {
 652         struct slave *tx_slave = NULL;
 653         struct arp_pkt *arp;
 654 
 655         if (!pskb_network_may_pull(skb, sizeof(*arp)))
 656                 return NULL;
 657         arp = (struct arp_pkt *)skb_network_header(skb);
 658 
 659         /* Don't modify or load balance ARPs that do not originate locally
 660          * (e.g.,arrive via a bridge).
 661          */
 662         if (!bond_slave_has_mac_rx(bond, arp->mac_src))
 663                 return NULL;
 664 
 665         if (arp->op_code == htons(ARPOP_REPLY)) {
 666                 /* the arp must be sent on the selected rx channel */
 667                 tx_slave = rlb_choose_channel(skb, bond, arp);
 668                 if (tx_slave)
 669                         bond_hw_addr_copy(arp->mac_src, tx_slave->dev->dev_addr,
 670                                           tx_slave->dev->addr_len);
 671                 netdev_dbg(bond->dev, "(slave %s): Server sent ARP Reply packet\n",
 672                            tx_slave ? tx_slave->dev->name : "NULL");
 673         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
 674                 /* Create an entry in the rx_hashtbl for this client as a
 675                  * place holder.
 676                  * When the arp reply is received the entry will be updated
 677                  * with the correct unicast address of the client.
 678                  */
 679                 tx_slave = rlb_choose_channel(skb, bond, arp);
 680 
 681                 /* The ARP reply packets must be delayed so that
 682                  * they can cancel out the influence of the ARP request.
 683                  */
 684                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 685 
 686                 /* arp requests are broadcast and are sent on the primary
 687                  * the arp request will collapse all clients on the subnet to
 688                  * the primary slave. We must register these clients to be
 689                  * updated with their assigned mac.
 690                  */
 691                 rlb_req_update_subnet_clients(bond, arp->ip_src);
 692                 netdev_dbg(bond->dev, "(slave %s): Server sent ARP Request packet\n",
 693                            tx_slave ? tx_slave->dev->name : "NULL");
 694         }
 695 
 696         return tx_slave;
 697 }
 698 
 699 static void rlb_rebalance(struct bonding *bond)
 700 {
 701         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 702         struct slave *assigned_slave;
 703         struct rlb_client_info *client_info;
 704         int ntt;
 705         u32 hash_index;
 706 
 707         spin_lock_bh(&bond->mode_lock);
 708 
 709         ntt = 0;
 710         hash_index = bond_info->rx_hashtbl_used_head;
 711         for (; hash_index != RLB_NULL_INDEX;
 712              hash_index = client_info->used_next) {
 713                 client_info = &(bond_info->rx_hashtbl[hash_index]);
 714                 assigned_slave = __rlb_next_rx_slave(bond);
 715                 if (assigned_slave && (client_info->slave != assigned_slave)) {
 716                         client_info->slave = assigned_slave;
 717                         if (!is_zero_ether_addr(client_info->mac_dst)) {
 718                                 client_info->ntt = 1;
 719                                 ntt = 1;
 720                         }
 721                 }
 722         }
 723 
 724         /* update the team's flag only after the whole iteration */
 725         if (ntt)
 726                 bond_info->rx_ntt = 1;
 727         spin_unlock_bh(&bond->mode_lock);
 728 }
 729 
 730 /* Caller must hold mode_lock */
 731 static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 732 {
 733         entry->used_next = RLB_NULL_INDEX;
 734         entry->used_prev = RLB_NULL_INDEX;
 735         entry->assigned = 0;
 736         entry->slave = NULL;
 737         entry->vlan_id = 0;
 738 }
 739 static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 740 {
 741         entry->src_first = RLB_NULL_INDEX;
 742         entry->src_prev = RLB_NULL_INDEX;
 743         entry->src_next = RLB_NULL_INDEX;
 744 }
 745 
 746 static void rlb_init_table_entry(struct rlb_client_info *entry)
 747 {
 748         memset(entry, 0, sizeof(struct rlb_client_info));
 749         rlb_init_table_entry_dst(entry);
 750         rlb_init_table_entry_src(entry);
 751 }
 752 
 753 static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 754 {
 755         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 756         u32 next_index = bond_info->rx_hashtbl[index].used_next;
 757         u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 758 
 759         if (index == bond_info->rx_hashtbl_used_head)
 760                 bond_info->rx_hashtbl_used_head = next_index;
 761         if (prev_index != RLB_NULL_INDEX)
 762                 bond_info->rx_hashtbl[prev_index].used_next = next_index;
 763         if (next_index != RLB_NULL_INDEX)
 764                 bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 765 }
 766 
 767 /* unlink a rlb hash table entry from the src list */
 768 static void rlb_src_unlink(struct bonding *bond, u32 index)
 769 {
 770         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 771         u32 next_index = bond_info->rx_hashtbl[index].src_next;
 772         u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 773 
 774         bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 775         bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 776 
 777         if (next_index != RLB_NULL_INDEX)
 778                 bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 779 
 780         if (prev_index == RLB_NULL_INDEX)
 781                 return;
 782 
 783         /* is prev_index pointing to the head of this list? */
 784         if (bond_info->rx_hashtbl[prev_index].src_first == index)
 785                 bond_info->rx_hashtbl[prev_index].src_first = next_index;
 786         else
 787                 bond_info->rx_hashtbl[prev_index].src_next = next_index;
 788 
 789 }
 790 
 791 static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 792 {
 793         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 794         struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 795 
 796         rlb_delete_table_entry_dst(bond, index);
 797         rlb_init_table_entry_dst(entry);
 798 
 799         rlb_src_unlink(bond, index);
 800 }
 801 
 802 /* add the rx_hashtbl[ip_dst_hash] entry to the list
 803  * of entries with identical ip_src_hash
 804  */
 805 static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 806 {
 807         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 808         u32 next;
 809 
 810         bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 811         next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 812         bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 813         if (next != RLB_NULL_INDEX)
 814                 bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 815         bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 816 }
 817 
 818 /* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
 819  * not match arp->mac_src
 820  */
 821 static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 822 {
 823         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 824         u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 825         u32 index;
 826 
 827         spin_lock_bh(&bond->mode_lock);
 828 
 829         index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 830         while (index != RLB_NULL_INDEX) {
 831                 struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 832                 u32 next_index = entry->src_next;
 833                 if (entry->ip_src == arp->ip_src &&
 834                     !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 835                                 rlb_delete_table_entry(bond, index);
 836                 index = next_index;
 837         }
 838         spin_unlock_bh(&bond->mode_lock);
 839 }
 840 
 841 static int rlb_initialize(struct bonding *bond)
 842 {
 843         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 844         struct rlb_client_info  *new_hashtbl;
 845         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 846         int i;
 847 
 848         new_hashtbl = kmalloc(size, GFP_KERNEL);
 849         if (!new_hashtbl)
 850                 return -1;
 851 
 852         spin_lock_bh(&bond->mode_lock);
 853 
 854         bond_info->rx_hashtbl = new_hashtbl;
 855 
 856         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 857 
 858         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 859                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
 860 
 861         spin_unlock_bh(&bond->mode_lock);
 862 
 863         /* register to receive ARPs */
 864         bond->recv_probe = rlb_arp_recv;
 865 
 866         return 0;
 867 }
 868 
 869 static void rlb_deinitialize(struct bonding *bond)
 870 {
 871         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 872 
 873         spin_lock_bh(&bond->mode_lock);
 874 
 875         kfree(bond_info->rx_hashtbl);
 876         bond_info->rx_hashtbl = NULL;
 877         bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 878 
 879         spin_unlock_bh(&bond->mode_lock);
 880 }
 881 
 882 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 883 {
 884         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 885         u32 curr_index;
 886 
 887         spin_lock_bh(&bond->mode_lock);
 888 
 889         curr_index = bond_info->rx_hashtbl_used_head;
 890         while (curr_index != RLB_NULL_INDEX) {
 891                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 892                 u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 893 
 894                 if (curr->vlan_id == vlan_id)
 895                         rlb_delete_table_entry(bond, curr_index);
 896 
 897                 curr_index = next_index;
 898         }
 899 
 900         spin_unlock_bh(&bond->mode_lock);
 901 }
 902 
 903 /*********************** tlb/rlb shared functions *********************/
 904 
 905 static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
 906                             __be16 vlan_proto, u16 vid)
 907 {
 908         struct learning_pkt pkt;
 909         struct sk_buff *skb;
 910         int size = sizeof(struct learning_pkt);
 911 
 912         memset(&pkt, 0, size);
 913         ether_addr_copy(pkt.mac_dst, mac_addr);
 914         ether_addr_copy(pkt.mac_src, mac_addr);
 915         pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
 916 
 917         skb = dev_alloc_skb(size);
 918         if (!skb)
 919                 return;
 920 
 921         skb_put_data(skb, &pkt, size);
 922 
 923         skb_reset_mac_header(skb);
 924         skb->network_header = skb->mac_header + ETH_HLEN;
 925         skb->protocol = pkt.type;
 926         skb->priority = TC_PRIO_CONTROL;
 927         skb->dev = slave->dev;
 928 
 929         slave_dbg(slave->bond->dev, slave->dev,
 930                   "Send learning packet: mac %pM vlan %d\n", mac_addr, vid);
 931 
 932         if (vid)
 933                 __vlan_hwaccel_put_tag(skb, vlan_proto, vid);
 934 
 935         dev_queue_xmit(skb);
 936 }
 937 
 938 struct alb_walk_data {
 939         struct bonding *bond;
 940         struct slave *slave;
 941         u8 *mac_addr;
 942         bool strict_match;
 943 };
 944 
 945 static int alb_upper_dev_walk(struct net_device *upper, void *_data)
 946 {
 947         struct alb_walk_data *data = _data;
 948         bool strict_match = data->strict_match;
 949         struct bonding *bond = data->bond;
 950         struct slave *slave = data->slave;
 951         u8 *mac_addr = data->mac_addr;
 952         struct bond_vlan_tag *tags;
 953 
 954         if (is_vlan_dev(upper) &&
 955             bond->dev->lower_level == upper->lower_level - 1) {
 956                 if (upper->addr_assign_type == NET_ADDR_STOLEN) {
 957                         alb_send_lp_vid(slave, mac_addr,
 958                                         vlan_dev_vlan_proto(upper),
 959                                         vlan_dev_vlan_id(upper));
 960                 } else {
 961                         alb_send_lp_vid(slave, upper->dev_addr,
 962                                         vlan_dev_vlan_proto(upper),
 963                                         vlan_dev_vlan_id(upper));
 964                 }
 965         }
 966 
 967         /* If this is a macvlan device, then only send updates
 968          * when strict_match is turned off.
 969          */
 970         if (netif_is_macvlan(upper) && !strict_match) {
 971                 tags = bond_verify_device_path(bond->dev, upper, 0);
 972                 if (IS_ERR_OR_NULL(tags))
 973                         BUG();
 974                 alb_send_lp_vid(slave, upper->dev_addr,
 975                                 tags[0].vlan_proto, tags[0].vlan_id);
 976                 kfree(tags);
 977         }
 978 
 979         return 0;
 980 }
 981 
 982 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
 983                                       bool strict_match)
 984 {
 985         struct bonding *bond = bond_get_bond_by_slave(slave);
 986         struct alb_walk_data data = {
 987                 .strict_match = strict_match,
 988                 .mac_addr = mac_addr,
 989                 .slave = slave,
 990                 .bond = bond,
 991         };
 992 
 993         /* send untagged */
 994         alb_send_lp_vid(slave, mac_addr, 0, 0);
 995 
 996         /* loop through all devices and see if we need to send a packet
 997          * for that device.
 998          */
 999         rcu_read_lock();
1000         netdev_walk_all_upper_dev_rcu(bond->dev, alb_upper_dev_walk, &data);
1001         rcu_read_unlock();
1002 }
1003 
1004 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[],
1005                                   unsigned int len)
1006 {
1007         struct net_device *dev = slave->dev;
1008         struct sockaddr_storage ss;
1009 
1010         if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1011                 memcpy(dev->dev_addr, addr, len);
1012                 return 0;
1013         }
1014 
1015         /* for rlb each slave must have a unique hw mac addresses so that
1016          * each slave will receive packets destined to a different mac
1017          */
1018         memcpy(ss.__data, addr, len);
1019         ss.ss_family = dev->type;
1020         if (dev_set_mac_address(dev, (struct sockaddr *)&ss, NULL)) {
1021                 slave_err(slave->bond->dev, dev, "dev_set_mac_address on slave failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n");
1022                 return -EOPNOTSUPP;
1023         }
1024         return 0;
1025 }
1026 
1027 /* Swap MAC addresses between two slaves.
1028  *
1029  * Called with RTNL held, and no other locks.
1030  */
1031 static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1032 {
1033         u8 tmp_mac_addr[MAX_ADDR_LEN];
1034 
1035         bond_hw_addr_copy(tmp_mac_addr, slave1->dev->dev_addr,
1036                           slave1->dev->addr_len);
1037         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr,
1038                                slave2->dev->addr_len);
1039         alb_set_slave_mac_addr(slave2, tmp_mac_addr,
1040                                slave1->dev->addr_len);
1041 
1042 }
1043 
1044 /* Send learning packets after MAC address swap.
1045  *
1046  * Called with RTNL and no other locks
1047  */
1048 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1049                                 struct slave *slave2)
1050 {
1051         int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1052         struct slave *disabled_slave = NULL;
1053 
1054         ASSERT_RTNL();
1055 
1056         /* fasten the change in the switch */
1057         if (bond_slave_can_tx(slave1)) {
1058                 alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1059                 if (bond->alb_info.rlb_enabled) {
1060                         /* inform the clients that the mac address
1061                          * has changed
1062                          */
1063                         rlb_req_update_slave_clients(bond, slave1);
1064                 }
1065         } else {
1066                 disabled_slave = slave1;
1067         }
1068 
1069         if (bond_slave_can_tx(slave2)) {
1070                 alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1071                 if (bond->alb_info.rlb_enabled) {
1072                         /* inform the clients that the mac address
1073                          * has changed
1074                          */
1075                         rlb_req_update_slave_clients(bond, slave2);
1076                 }
1077         } else {
1078                 disabled_slave = slave2;
1079         }
1080 
1081         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1082                 /* A disabled slave was assigned an active mac addr */
1083                 rlb_teach_disabled_mac_on_primary(bond,
1084                                                   disabled_slave->dev->dev_addr);
1085         }
1086 }
1087 
1088 /**
1089  * alb_change_hw_addr_on_detach
1090  * @bond: bonding we're working on
1091  * @slave: the slave that was just detached
1092  *
1093  * We assume that @slave was already detached from the slave list.
1094  *
1095  * If @slave's permanent hw address is different both from its current
1096  * address and from @bond's address, then somewhere in the bond there's
1097  * a slave that has @slave's permanet address as its current address.
1098  * We'll make sure that that slave no longer uses @slave's permanent address.
1099  *
1100  * Caller must hold RTNL and no other locks
1101  */
1102 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1103 {
1104         int perm_curr_diff;
1105         int perm_bond_diff;
1106         struct slave *found_slave;
1107 
1108         perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1109                                                   slave->dev->dev_addr);
1110         perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1111                                                   bond->dev->dev_addr);
1112 
1113         if (perm_curr_diff && perm_bond_diff) {
1114                 found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1115 
1116                 if (found_slave) {
1117                         alb_swap_mac_addr(slave, found_slave);
1118                         alb_fasten_mac_swap(bond, slave, found_slave);
1119                 }
1120         }
1121 }
1122 
1123 /**
1124  * alb_handle_addr_collision_on_attach
1125  * @bond: bonding we're working on
1126  * @slave: the slave that was just attached
1127  *
1128  * checks uniqueness of slave's mac address and handles the case the
1129  * new slave uses the bonds mac address.
1130  *
1131  * If the permanent hw address of @slave is @bond's hw address, we need to
1132  * find a different hw address to give @slave, that isn't in use by any other
1133  * slave in the bond. This address must be, of course, one of the permanent
1134  * addresses of the other slaves.
1135  *
1136  * We go over the slave list, and for each slave there we compare its
1137  * permanent hw address with the current address of all the other slaves.
1138  * If no match was found, then we've found a slave with a permanent address
1139  * that isn't used by any other slave in the bond, so we can assign it to
1140  * @slave.
1141  *
1142  * assumption: this function is called before @slave is attached to the
1143  *             bond slave list.
1144  */
1145 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1146 {
1147         struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1148         struct slave *tmp_slave1, *free_mac_slave = NULL;
1149         struct list_head *iter;
1150 
1151         if (!bond_has_slaves(bond)) {
1152                 /* this is the first slave */
1153                 return 0;
1154         }
1155 
1156         /* if slave's mac address differs from bond's mac address
1157          * check uniqueness of slave's mac address against the other
1158          * slaves in the bond.
1159          */
1160         if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1161                 if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1162                         return 0;
1163 
1164                 /* Try setting slave mac to bond address and fall-through
1165                  * to code handling that situation below...
1166                  */
1167                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1168                                        bond->dev->addr_len);
1169         }
1170 
1171         /* The slave's address is equal to the address of the bond.
1172          * Search for a spare address in the bond for this slave.
1173          */
1174         bond_for_each_slave(bond, tmp_slave1, iter) {
1175                 if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1176                         /* no slave has tmp_slave1's perm addr
1177                          * as its curr addr
1178                          */
1179                         free_mac_slave = tmp_slave1;
1180                         break;
1181                 }
1182 
1183                 if (!has_bond_addr) {
1184                         if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1185                                                     bond->dev->dev_addr)) {
1186 
1187                                 has_bond_addr = tmp_slave1;
1188                         }
1189                 }
1190         }
1191 
1192         if (free_mac_slave) {
1193                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1194                                        free_mac_slave->dev->addr_len);
1195 
1196                 slave_warn(bond->dev, slave->dev, "the slave hw address is in use by the bond; giving it the hw address of %s\n",
1197                            free_mac_slave->dev->name);
1198 
1199         } else if (has_bond_addr) {
1200                 slave_err(bond->dev, slave->dev, "the slave hw address 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");
1201                 return -EFAULT;
1202         }
1203 
1204         return 0;
1205 }
1206 
1207 /**
1208  * alb_set_mac_address
1209  * @bond:
1210  * @addr:
1211  *
1212  * In TLB mode all slaves are configured to the bond's hw address, but set
1213  * their dev_addr field to different addresses (based on their permanent hw
1214  * addresses).
1215  *
1216  * For each slave, this function sets the interface to the new address and then
1217  * changes its dev_addr field to its previous value.
1218  *
1219  * Unwinding assumes bond's mac address has not yet changed.
1220  */
1221 static int alb_set_mac_address(struct bonding *bond, void *addr)
1222 {
1223         struct slave *slave, *rollback_slave;
1224         struct list_head *iter;
1225         struct sockaddr_storage ss;
1226         char tmp_addr[MAX_ADDR_LEN];
1227         int res;
1228 
1229         if (bond->alb_info.rlb_enabled)
1230                 return 0;
1231 
1232         bond_for_each_slave(bond, slave, iter) {
1233                 /* save net_device's current hw address */
1234                 bond_hw_addr_copy(tmp_addr, slave->dev->dev_addr,
1235                                   slave->dev->addr_len);
1236 
1237                 res = dev_set_mac_address(slave->dev, addr, NULL);
1238 
1239                 /* restore net_device's hw address */
1240                 bond_hw_addr_copy(slave->dev->dev_addr, tmp_addr,
1241                                   slave->dev->addr_len);
1242 
1243                 if (res)
1244                         goto unwind;
1245         }
1246 
1247         return 0;
1248 
1249 unwind:
1250         memcpy(ss.__data, bond->dev->dev_addr, bond->dev->addr_len);
1251         ss.ss_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                 bond_hw_addr_copy(tmp_addr, rollback_slave->dev->dev_addr,
1258                                   rollback_slave->dev->addr_len);
1259                 dev_set_mac_address(rollback_slave->dev,
1260                                     (struct sockaddr *)&ss, NULL);
1261                 bond_hw_addr_copy(rollback_slave->dev->dev_addr, tmp_addr,
1262                                   rollback_slave->dev->addr_len);
1263         }
1264 
1265         return res;
1266 }
1267 
1268 /************************ exported alb funcions ************************/
1269 
1270 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1271 {
1272         int res;
1273 
1274         res = tlb_initialize(bond);
1275         if (res)
1276                 return res;
1277 
1278         if (rlb_enabled) {
1279                 bond->alb_info.rlb_enabled = 1;
1280                 res = rlb_initialize(bond);
1281                 if (res) {
1282                         tlb_deinitialize(bond);
1283                         return res;
1284                 }
1285         } else {
1286                 bond->alb_info.rlb_enabled = 0;
1287         }
1288 
1289         return 0;
1290 }
1291 
1292 void bond_alb_deinitialize(struct bonding *bond)
1293 {
1294         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1295 
1296         tlb_deinitialize(bond);
1297 
1298         if (bond_info->rlb_enabled)
1299                 rlb_deinitialize(bond);
1300 }
1301 
1302 static netdev_tx_t bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1303                                     struct slave *tx_slave)
1304 {
1305         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1306         struct ethhdr *eth_data = eth_hdr(skb);
1307 
1308         if (!tx_slave) {
1309                 /* unbalanced or unassigned, send through primary */
1310                 tx_slave = rcu_dereference(bond->curr_active_slave);
1311                 if (bond->params.tlb_dynamic_lb)
1312                         bond_info->unbalanced_load += skb->len;
1313         }
1314 
1315         if (tx_slave && bond_slave_can_tx(tx_slave)) {
1316                 if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1317                         ether_addr_copy(eth_data->h_source,
1318                                         tx_slave->dev->dev_addr);
1319                 }
1320 
1321                 bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1322                 goto out;
1323         }
1324 
1325         if (tx_slave && bond->params.tlb_dynamic_lb) {
1326                 spin_lock(&bond->mode_lock);
1327                 __tlb_clear_slave(bond, tx_slave, 0);
1328                 spin_unlock(&bond->mode_lock);
1329         }
1330 
1331         /* no suitable interface, frame not sent */
1332         bond_tx_drop(bond->dev, skb);
1333 out:
1334         return NETDEV_TX_OK;
1335 }
1336 
1337 netdev_tx_t bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1338 {
1339         struct bonding *bond = netdev_priv(bond_dev);
1340         struct ethhdr *eth_data;
1341         struct slave *tx_slave = NULL;
1342         u32 hash_index;
1343 
1344         skb_reset_mac_header(skb);
1345         eth_data = eth_hdr(skb);
1346 
1347         /* Do not TX balance any multicast or broadcast */
1348         if (!is_multicast_ether_addr(eth_data->h_dest)) {
1349                 switch (skb->protocol) {
1350                 case htons(ETH_P_IP):
1351                 case htons(ETH_P_IPX):
1352                     /* In case of IPX, it will falback to L2 hash */
1353                 case htons(ETH_P_IPV6):
1354                         hash_index = bond_xmit_hash(bond, skb);
1355                         if (bond->params.tlb_dynamic_lb) {
1356                                 tx_slave = tlb_choose_channel(bond,
1357                                                               hash_index & 0xFF,
1358                                                               skb->len);
1359                         } else {
1360                                 struct bond_up_slave *slaves;
1361                                 unsigned int count;
1362 
1363                                 slaves = rcu_dereference(bond->slave_arr);
1364                                 count = slaves ? READ_ONCE(slaves->count) : 0;
1365                                 if (likely(count))
1366                                         tx_slave = slaves->arr[hash_index %
1367                                                                count];
1368                         }
1369                         break;
1370                 }
1371         }
1372         return bond_do_alb_xmit(skb, bond, tx_slave);
1373 }
1374 
1375 netdev_tx_t bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1376 {
1377         struct bonding *bond = netdev_priv(bond_dev);
1378         struct ethhdr *eth_data;
1379         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1380         struct slave *tx_slave = NULL;
1381         static const __be32 ip_bcast = htonl(0xffffffff);
1382         int hash_size = 0;
1383         bool do_tx_balance = true;
1384         u32 hash_index = 0;
1385         const u8 *hash_start = NULL;
1386 
1387         skb_reset_mac_header(skb);
1388         eth_data = eth_hdr(skb);
1389 
1390         switch (ntohs(skb->protocol)) {
1391         case ETH_P_IP: {
1392                 const struct iphdr *iph;
1393 
1394                 if (is_broadcast_ether_addr(eth_data->h_dest) ||
1395                     !pskb_network_may_pull(skb, sizeof(*iph))) {
1396                         do_tx_balance = false;
1397                         break;
1398                 }
1399                 iph = ip_hdr(skb);
1400                 if (iph->daddr == ip_bcast || iph->protocol == IPPROTO_IGMP) {
1401                         do_tx_balance = false;
1402                         break;
1403                 }
1404                 hash_start = (char *)&(iph->daddr);
1405                 hash_size = sizeof(iph->daddr);
1406                 break;
1407         }
1408         case ETH_P_IPV6: {
1409                 const struct ipv6hdr *ip6hdr;
1410 
1411                 /* IPv6 doesn't really use broadcast mac address, but leave
1412                  * that here just in case.
1413                  */
1414                 if (is_broadcast_ether_addr(eth_data->h_dest)) {
1415                         do_tx_balance = false;
1416                         break;
1417                 }
1418 
1419                 /* IPv6 uses all-nodes multicast as an equivalent to
1420                  * broadcasts in IPv4.
1421                  */
1422                 if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1423                         do_tx_balance = false;
1424                         break;
1425                 }
1426 
1427                 if (!pskb_network_may_pull(skb, sizeof(*ip6hdr))) {
1428                         do_tx_balance = false;
1429                         break;
1430                 }
1431                 /* Additionally, DAD probes should not be tx-balanced as that
1432                  * will lead to false positives for duplicate addresses and
1433                  * prevent address configuration from working.
1434                  */
1435                 ip6hdr = ipv6_hdr(skb);
1436                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1437                         do_tx_balance = false;
1438                         break;
1439                 }
1440 
1441                 hash_start = (char *)&ip6hdr->daddr;
1442                 hash_size = sizeof(ip6hdr->daddr);
1443                 break;
1444         }
1445         case ETH_P_IPX: {
1446                 const struct ipxhdr *ipxhdr;
1447 
1448                 if (pskb_network_may_pull(skb, sizeof(*ipxhdr))) {
1449                         do_tx_balance = false;
1450                         break;
1451                 }
1452                 ipxhdr = (struct ipxhdr *)skb_network_header(skb);
1453 
1454                 if (ipxhdr->ipx_checksum != IPX_NO_CHECKSUM) {
1455                         /* something is wrong with this packet */
1456                         do_tx_balance = false;
1457                         break;
1458                 }
1459 
1460                 if (ipxhdr->ipx_type != IPX_TYPE_NCP) {
1461                         /* The only protocol worth balancing in
1462                          * this family since it has an "ARP" like
1463                          * mechanism
1464                          */
1465                         do_tx_balance = false;
1466                         break;
1467                 }
1468 
1469                 eth_data = eth_hdr(skb);
1470                 hash_start = (char *)eth_data->h_dest;
1471                 hash_size = ETH_ALEN;
1472                 break;
1473         }
1474         case ETH_P_ARP:
1475                 do_tx_balance = false;
1476                 if (bond_info->rlb_enabled)
1477                         tx_slave = rlb_arp_xmit(skb, bond);
1478                 break;
1479         default:
1480                 do_tx_balance = false;
1481                 break;
1482         }
1483 
1484         if (do_tx_balance) {
1485                 if (bond->params.tlb_dynamic_lb) {
1486                         hash_index = _simple_hash(hash_start, hash_size);
1487                         tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1488                 } else {
1489                         /*
1490                          * do_tx_balance means we are free to select the tx_slave
1491                          * So we do exactly what tlb would do for hash selection
1492                          */
1493 
1494                         struct bond_up_slave *slaves;
1495                         unsigned int count;
1496 
1497                         slaves = rcu_dereference(bond->slave_arr);
1498                         count = slaves ? READ_ONCE(slaves->count) : 0;
1499                         if (likely(count))
1500                                 tx_slave = slaves->arr[bond_xmit_hash(bond, skb) %
1501                                                        count];
1502                 }
1503         }
1504 
1505         return bond_do_alb_xmit(skb, bond, tx_slave);
1506 }
1507 
1508 void bond_alb_monitor(struct work_struct *work)
1509 {
1510         struct bonding *bond = container_of(work, struct bonding,
1511                                             alb_work.work);
1512         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1513         struct list_head *iter;
1514         struct slave *slave;
1515 
1516         if (!bond_has_slaves(bond)) {
1517                 bond_info->tx_rebalance_counter = 0;
1518                 bond_info->lp_counter = 0;
1519                 goto re_arm;
1520         }
1521 
1522         rcu_read_lock();
1523 
1524         bond_info->tx_rebalance_counter++;
1525         bond_info->lp_counter++;
1526 
1527         /* send learning packets */
1528         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1529                 bool strict_match;
1530 
1531                 bond_for_each_slave_rcu(bond, slave, iter) {
1532                         /* If updating current_active, use all currently
1533                          * user mac addreses (!strict_match).  Otherwise, only
1534                          * use mac of the slave device.
1535                          * In RLB mode, we always use strict matches.
1536                          */
1537                         strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1538                                         bond_info->rlb_enabled);
1539                         alb_send_learning_packets(slave, slave->dev->dev_addr,
1540                                                   strict_match);
1541                 }
1542                 bond_info->lp_counter = 0;
1543         }
1544 
1545         /* rebalance tx traffic */
1546         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1547                 bond_for_each_slave_rcu(bond, slave, iter) {
1548                         tlb_clear_slave(bond, slave, 1);
1549                         if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1550                                 SLAVE_TLB_INFO(slave).load =
1551                                         bond_info->unbalanced_load /
1552                                                 BOND_TLB_REBALANCE_INTERVAL;
1553                                 bond_info->unbalanced_load = 0;
1554                         }
1555                 }
1556                 bond_info->tx_rebalance_counter = 0;
1557         }
1558 
1559         if (bond_info->rlb_enabled) {
1560                 if (bond_info->primary_is_promisc &&
1561                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1562 
1563                         /* dev_set_promiscuity requires rtnl and
1564                          * nothing else.  Avoid race with bond_close.
1565                          */
1566                         rcu_read_unlock();
1567                         if (!rtnl_trylock())
1568                                 goto re_arm;
1569 
1570                         bond_info->rlb_promisc_timeout_counter = 0;
1571 
1572                         /* If the primary was set to promiscuous mode
1573                          * because a slave was disabled then
1574                          * it can now leave promiscuous mode.
1575                          */
1576                         dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1577                                             -1);
1578                         bond_info->primary_is_promisc = 0;
1579 
1580                         rtnl_unlock();
1581                         rcu_read_lock();
1582                 }
1583 
1584                 if (bond_info->rlb_rebalance) {
1585                         bond_info->rlb_rebalance = 0;
1586                         rlb_rebalance(bond);
1587                 }
1588 
1589                 /* check if clients need updating */
1590                 if (bond_info->rx_ntt) {
1591                         if (bond_info->rlb_update_delay_counter) {
1592                                 --bond_info->rlb_update_delay_counter;
1593                         } else {
1594                                 rlb_update_rx_clients(bond);
1595                                 if (bond_info->rlb_update_retry_counter)
1596                                         --bond_info->rlb_update_retry_counter;
1597                                 else
1598                                         bond_info->rx_ntt = 0;
1599                         }
1600                 }
1601         }
1602         rcu_read_unlock();
1603 re_arm:
1604         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1605 }
1606 
1607 /* assumption: called before the slave is attached to the bond
1608  * and not locked by the bond lock
1609  */
1610 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1611 {
1612         int res;
1613 
1614         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1615                                      slave->dev->addr_len);
1616         if (res)
1617                 return res;
1618 
1619         res = alb_handle_addr_collision_on_attach(bond, slave);
1620         if (res)
1621                 return res;
1622 
1623         tlb_init_slave(slave);
1624 
1625         /* order a rebalance ASAP */
1626         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1627 
1628         if (bond->alb_info.rlb_enabled)
1629                 bond->alb_info.rlb_rebalance = 1;
1630 
1631         return 0;
1632 }
1633 
1634 /* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1635  * if necessary.
1636  *
1637  * Caller must hold RTNL and no other locks
1638  */
1639 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1640 {
1641         if (bond_has_slaves(bond))
1642                 alb_change_hw_addr_on_detach(bond, slave);
1643 
1644         tlb_clear_slave(bond, slave, 0);
1645 
1646         if (bond->alb_info.rlb_enabled) {
1647                 bond->alb_info.rx_slave = NULL;
1648                 rlb_clear_slave(bond, slave);
1649         }
1650 
1651 }
1652 
1653 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1654 {
1655         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1656 
1657         if (link == BOND_LINK_DOWN) {
1658                 tlb_clear_slave(bond, slave, 0);
1659                 if (bond->alb_info.rlb_enabled)
1660                         rlb_clear_slave(bond, slave);
1661         } else if (link == BOND_LINK_UP) {
1662                 /* order a rebalance ASAP */
1663                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1664                 if (bond->alb_info.rlb_enabled) {
1665                         bond->alb_info.rlb_rebalance = 1;
1666                         /* If the updelay module parameter is smaller than the
1667                          * forwarding delay of the switch the rebalance will
1668                          * not work because the rebalance arp replies will
1669                          * not be forwarded to the clients..
1670                          */
1671                 }
1672         }
1673 
1674         if (bond_is_nondyn_tlb(bond)) {
1675                 if (bond_update_slave_arr(bond, NULL))
1676                         pr_err("Failed to build slave-array for TLB mode.\n");
1677         }
1678 }
1679 
1680 /**
1681  * bond_alb_handle_active_change - assign new curr_active_slave
1682  * @bond: our bonding struct
1683  * @new_slave: new slave to assign
1684  *
1685  * Set the bond->curr_active_slave to @new_slave and handle
1686  * mac address swapping and promiscuity changes as needed.
1687  *
1688  * Caller must hold RTNL
1689  */
1690 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1691 {
1692         struct slave *swap_slave;
1693         struct slave *curr_active;
1694 
1695         curr_active = rtnl_dereference(bond->curr_active_slave);
1696         if (curr_active == new_slave)
1697                 return;
1698 
1699         if (curr_active && bond->alb_info.primary_is_promisc) {
1700                 dev_set_promiscuity(curr_active->dev, -1);
1701                 bond->alb_info.primary_is_promisc = 0;
1702                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1703         }
1704 
1705         swap_slave = curr_active;
1706         rcu_assign_pointer(bond->curr_active_slave, new_slave);
1707 
1708         if (!new_slave || !bond_has_slaves(bond))
1709                 return;
1710 
1711         /* set the new curr_active_slave to the bonds mac address
1712          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1713          */
1714         if (!swap_slave)
1715                 swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1716 
1717         /* Arrange for swap_slave and new_slave to temporarily be
1718          * ignored so we can mess with their MAC addresses without
1719          * fear of interference from transmit activity.
1720          */
1721         if (swap_slave)
1722                 tlb_clear_slave(bond, swap_slave, 1);
1723         tlb_clear_slave(bond, new_slave, 1);
1724 
1725         /* in TLB mode, the slave might flip down/up with the old dev_addr,
1726          * and thus filter bond->dev_addr's packets, so force bond's mac
1727          */
1728         if (BOND_MODE(bond) == BOND_MODE_TLB) {
1729                 struct sockaddr_storage ss;
1730                 u8 tmp_addr[MAX_ADDR_LEN];
1731 
1732                 bond_hw_addr_copy(tmp_addr, new_slave->dev->dev_addr,
1733                                   new_slave->dev->addr_len);
1734 
1735                 bond_hw_addr_copy(ss.__data, bond->dev->dev_addr,
1736                                   bond->dev->addr_len);
1737                 ss.ss_family = bond->dev->type;
1738                 /* we don't care if it can't change its mac, best effort */
1739                 dev_set_mac_address(new_slave->dev, (struct sockaddr *)&ss,
1740                                     NULL);
1741 
1742                 bond_hw_addr_copy(new_slave->dev->dev_addr, tmp_addr,
1743                                   new_slave->dev->addr_len);
1744         }
1745 
1746         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1747         if (swap_slave) {
1748                 /* swap mac address */
1749                 alb_swap_mac_addr(swap_slave, new_slave);
1750                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1751         } else {
1752                 /* set the new_slave to the bond mac address */
1753                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1754                                        bond->dev->addr_len);
1755                 alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1756                                           false);
1757         }
1758 }
1759 
1760 /* Called with RTNL */
1761 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1762 {
1763         struct bonding *bond = netdev_priv(bond_dev);
1764         struct sockaddr_storage *ss = addr;
1765         struct slave *curr_active;
1766         struct slave *swap_slave;
1767         int res;
1768 
1769         if (!is_valid_ether_addr(ss->__data))
1770                 return -EADDRNOTAVAIL;
1771 
1772         res = alb_set_mac_address(bond, addr);
1773         if (res)
1774                 return res;
1775 
1776         bond_hw_addr_copy(bond_dev->dev_addr, ss->__data, bond_dev->addr_len);
1777 
1778         /* If there is no curr_active_slave there is nothing else to do.
1779          * Otherwise we'll need to pass the new address to it and handle
1780          * duplications.
1781          */
1782         curr_active = rtnl_dereference(bond->curr_active_slave);
1783         if (!curr_active)
1784                 return 0;
1785 
1786         swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1787 
1788         if (swap_slave) {
1789                 alb_swap_mac_addr(swap_slave, curr_active);
1790                 alb_fasten_mac_swap(bond, swap_slave, curr_active);
1791         } else {
1792                 alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr,
1793                                        bond_dev->addr_len);
1794 
1795                 alb_send_learning_packets(curr_active,
1796                                           bond_dev->dev_addr, false);
1797                 if (bond->alb_info.rlb_enabled) {
1798                         /* inform clients mac address has changed */
1799                         rlb_req_update_slave_clients(bond, curr_active);
1800                 }
1801         }
1802 
1803         return 0;
1804 }
1805 
1806 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1807 {
1808         if (bond->alb_info.rlb_enabled)
1809                 rlb_clear_vlan(bond, vlan_id);
1810 }
1811
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/net/bonding/bond_alb.c

DEFINITIONS
