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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24#include <linux/skbuff.h>
  25#include <linux/netdevice.h>
  26#include <linux/etherdevice.h>
  27#include <linux/pkt_sched.h>
  28#include <linux/spinlock.h>
  29#include <linux/slab.h>
  30#include <linux/timer.h>
  31#include <linux/ip.h>
  32#include <linux/ipv6.h>
  33#include <linux/if_arp.h>
  34#include <linux/if_ether.h>
  35#include <linux/if_bonding.h>
  36#include <linux/if_vlan.h>
  37#include <linux/in.h>
  38#include <net/ipx.h>
  39#include <net/arp.h>
  40#include <net/ipv6.h>
 
  41#include <asm/byteorder.h>
  42#include "bonding.h"
  43#include "bond_alb.h"
  44
  45
  46
  47#ifndef __long_aligned
  48#define __long_aligned __attribute__((aligned((sizeof(long)))))
  49#endif
  50static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
  51	0xff, 0xff, 0xff, 0xff, 0xff, 0xff
  52};
  53static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
  54	0x33, 0x33, 0x00, 0x00, 0x00, 0x01
  55};
  56static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
  57
  58#pragma pack(1)
  59struct learning_pkt {
  60	u8 mac_dst[ETH_ALEN];
  61	u8 mac_src[ETH_ALEN];
  62	__be16 type;
  63	u8 padding[ETH_ZLEN - ETH_HLEN];
  64};
  65
  66struct arp_pkt {
  67	__be16  hw_addr_space;
  68	__be16  prot_addr_space;
  69	u8      hw_addr_len;
  70	u8      prot_addr_len;
  71	__be16  op_code;
  72	u8      mac_src[ETH_ALEN];	/* sender hardware address */
  73	__be32  ip_src;			/* sender IP address */
  74	u8      mac_dst[ETH_ALEN];	/* target hardware address */
  75	__be32  ip_dst;			/* target IP address */
  76};
  77#pragma pack()
  78
  79static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
  80{
  81	return (struct arp_pkt *)skb_network_header(skb);
  82}
  83
  84/* Forward declaration */
  85static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
  86				      bool strict_match);
  87static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
  88static void rlb_src_unlink(struct bonding *bond, u32 index);
  89static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
  90			 u32 ip_dst_hash);
  91
  92static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
  93{
  94	int i;
  95	u8 hash = 0;
  96
  97	for (i = 0; i < hash_size; i++)
  98		hash ^= hash_start[i];
  99
 100	return hash;
 101}
 102
 103/*********************** tlb specific functions ***************************/
 104
 105static inline void _lock_tx_hashtbl_bh(struct bonding *bond)
 106{
 107	spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 108}
 109
 110static inline void _unlock_tx_hashtbl_bh(struct bonding *bond)
 111{
 112	spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 113}
 114
 115static inline void _lock_tx_hashtbl(struct bonding *bond)
 116{
 117	spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 118}
 119
 120static inline void _unlock_tx_hashtbl(struct bonding *bond)
 121{
 122	spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
 123}
 124
 125/* Caller must hold tx_hashtbl lock */
 126static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
 127{
 128	if (save_load) {
 129		entry->load_history = 1 + entry->tx_bytes /
 130				      BOND_TLB_REBALANCE_INTERVAL;
 131		entry->tx_bytes = 0;
 132	}
 133
 134	entry->tx_slave = NULL;
 135	entry->next = TLB_NULL_INDEX;
 136	entry->prev = TLB_NULL_INDEX;
 137}
 138
 139static inline void tlb_init_slave(struct slave *slave)
 140{
 141	SLAVE_TLB_INFO(slave).load = 0;
 142	SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
 143}
 144
 145/* Caller must hold bond lock for read, BH disabled */
 146static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
 147			 int save_load)
 148{
 149	struct tlb_client_info *tx_hash_table;
 150	u32 index;
 151
 152	/* clear slave from tx_hashtbl */
 153	tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
 154
 155	/* skip this if we've already freed the tx hash table */
 156	if (tx_hash_table) {
 157		index = SLAVE_TLB_INFO(slave).head;
 158		while (index != TLB_NULL_INDEX) {
 159			u32 next_index = tx_hash_table[index].next;
 
 160			tlb_init_table_entry(&tx_hash_table[index], save_load);
 161			index = next_index;
 162		}
 163	}
 164
 165	tlb_init_slave(slave);
 166}
 167
 168/* Caller must hold bond lock for read */
 169static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
 170			 int save_load)
 171{
 172	_lock_tx_hashtbl_bh(bond);
 173	__tlb_clear_slave(bond, slave, save_load);
 174	_unlock_tx_hashtbl_bh(bond);
 175}
 176
 177/* Must be called before starting the monitor timer */
 178static int tlb_initialize(struct bonding *bond)
 179{
 180	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 181	int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
 182	struct tlb_client_info *new_hashtbl;
 183	int i;
 184
 185	new_hashtbl = kzalloc(size, GFP_KERNEL);
 186	if (!new_hashtbl)
 187		return -1;
 188
 189	_lock_tx_hashtbl_bh(bond);
 190
 191	bond_info->tx_hashtbl = new_hashtbl;
 192
 193	for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
 194		tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
 195
 196	_unlock_tx_hashtbl_bh(bond);
 197
 198	return 0;
 199}
 200
 201/* Must be called only after all slaves have been released */
 202static void tlb_deinitialize(struct bonding *bond)
 203{
 204	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 205
 206	_lock_tx_hashtbl_bh(bond);
 207
 208	kfree(bond_info->tx_hashtbl);
 209	bond_info->tx_hashtbl = NULL;
 210
 211	_unlock_tx_hashtbl_bh(bond);
 212}
 213
 214static long long compute_gap(struct slave *slave)
 215{
 216	return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
 217	       (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
 218}
 219
 220/* Caller must hold bond lock for read */
 221static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
 222{
 223	struct slave *slave, *least_loaded;
 224	struct list_head *iter;
 225	long long max_gap;
 226
 227	least_loaded = NULL;
 228	max_gap = LLONG_MIN;
 229
 230	/* Find the slave with the largest gap */
 231	bond_for_each_slave_rcu(bond, slave, iter) {
 232		if (SLAVE_IS_OK(slave)) {
 233			long long gap = compute_gap(slave);
 234
 235			if (max_gap < gap) {
 236				least_loaded = slave;
 237				max_gap = gap;
 238			}
 239		}
 240	}
 241
 242	return least_loaded;
 243}
 244
 245static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
 246						u32 skb_len)
 247{
 248	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 249	struct tlb_client_info *hash_table;
 250	struct slave *assigned_slave;
 251
 252	hash_table = bond_info->tx_hashtbl;
 253	assigned_slave = hash_table[hash_index].tx_slave;
 254	if (!assigned_slave) {
 255		assigned_slave = tlb_get_least_loaded_slave(bond);
 256
 257		if (assigned_slave) {
 258			struct tlb_slave_info *slave_info =
 259				&(SLAVE_TLB_INFO(assigned_slave));
 260			u32 next_index = slave_info->head;
 261
 262			hash_table[hash_index].tx_slave = assigned_slave;
 263			hash_table[hash_index].next = next_index;
 264			hash_table[hash_index].prev = TLB_NULL_INDEX;
 265
 266			if (next_index != TLB_NULL_INDEX)
 267				hash_table[next_index].prev = hash_index;
 268
 269			slave_info->head = hash_index;
 270			slave_info->load +=
 271				hash_table[hash_index].load_history;
 272		}
 273	}
 274
 275	if (assigned_slave)
 276		hash_table[hash_index].tx_bytes += skb_len;
 277
 278	return assigned_slave;
 279}
 280
 281/* Caller must hold bond lock for read */
 282static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
 283					u32 skb_len)
 284{
 285	struct slave *tx_slave;
 286	/*
 287	 * We don't need to disable softirq here, becase
 288	 * tlb_choose_channel() is only called by bond_alb_xmit()
 289	 * which already has softirq disabled.
 290	 */
 291	_lock_tx_hashtbl(bond);
 292	tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
 293	_unlock_tx_hashtbl(bond);
 
 294	return tx_slave;
 295}
 296
 297/*********************** rlb specific functions ***************************/
 298static inline void _lock_rx_hashtbl_bh(struct bonding *bond)
 299{
 300	spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 301}
 302
 303static inline void _unlock_rx_hashtbl_bh(struct bonding *bond)
 304{
 305	spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 306}
 307
 308static inline void _lock_rx_hashtbl(struct bonding *bond)
 309{
 310	spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 311}
 312
 313static inline void _unlock_rx_hashtbl(struct bonding *bond)
 314{
 315	spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
 316}
 317
 318/* when an ARP REPLY is received from a client update its info
 319 * in the rx_hashtbl
 320 */
 321static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
 322{
 323	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 324	struct rlb_client_info *client_info;
 325	u32 hash_index;
 326
 327	_lock_rx_hashtbl_bh(bond);
 328
 329	hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 330	client_info = &(bond_info->rx_hashtbl[hash_index]);
 331
 332	if ((client_info->assigned) &&
 333	    (client_info->ip_src == arp->ip_dst) &&
 334	    (client_info->ip_dst == arp->ip_src) &&
 335	    (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
 336		/* update the clients MAC address */
 337		ether_addr_copy(client_info->mac_dst, arp->mac_src);
 338		client_info->ntt = 1;
 339		bond_info->rx_ntt = 1;
 340	}
 341
 342	_unlock_rx_hashtbl_bh(bond);
 343}
 344
 345static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
 346			struct slave *slave)
 347{
 348	struct arp_pkt *arp, _arp;
 349
 350	if (skb->protocol != cpu_to_be16(ETH_P_ARP))
 351		goto out;
 352
 353	arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
 354	if (!arp)
 355		goto out;
 356
 357	/* We received an ARP from arp->ip_src.
 358	 * We might have used this IP address previously (on the bonding host
 359	 * itself or on a system that is bridged together with the bond).
 360	 * However, if arp->mac_src is different than what is stored in
 361	 * rx_hashtbl, some other host is now using the IP and we must prevent
 362	 * sending out client updates with this IP address and the old MAC
 363	 * address.
 364	 * Clean up all hash table entries that have this address as ip_src but
 365	 * have a different mac_src.
 366	 */
 367	rlb_purge_src_ip(bond, arp);
 368
 369	if (arp->op_code == htons(ARPOP_REPLY)) {
 370		/* update rx hash table for this ARP */
 371		rlb_update_entry_from_arp(bond, arp);
 372		pr_debug("Server received an ARP Reply from client\n");
 373	}
 374out:
 375	return RX_HANDLER_ANOTHER;
 376}
 377
 378/* Caller must hold bond lock for read */
 379static struct slave *rlb_next_rx_slave(struct bonding *bond)
 380{
 381	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 382	struct slave *before = NULL, *rx_slave = NULL, *slave;
 383	struct list_head *iter;
 384	bool found = false;
 385
 386	bond_for_each_slave(bond, slave, iter) {
 387		if (!SLAVE_IS_OK(slave))
 388			continue;
 389		if (!found) {
 390			if (!before || before->speed < slave->speed)
 391				before = slave;
 392		} else {
 393			if (!rx_slave || rx_slave->speed < slave->speed)
 394				rx_slave = slave;
 395		}
 396		if (slave == bond_info->rx_slave)
 397			found = true;
 398	}
 399	/* we didn't find anything after the current or we have something
 400	 * better before and up to the current slave
 401	 */
 402	if (!rx_slave || (before && rx_slave->speed < before->speed))
 403		rx_slave = before;
 404
 405	if (rx_slave)
 406		bond_info->rx_slave = rx_slave;
 407
 408	return rx_slave;
 409}
 410
 411/* Caller must hold rcu_read_lock() for read */
 412static struct slave *__rlb_next_rx_slave(struct bonding *bond)
 413{
 414	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 415	struct slave *before = NULL, *rx_slave = NULL, *slave;
 416	struct list_head *iter;
 417	bool found = false;
 418
 419	bond_for_each_slave_rcu(bond, slave, iter) {
 420		if (!SLAVE_IS_OK(slave))
 421			continue;
 422		if (!found) {
 423			if (!before || before->speed < slave->speed)
 424				before = slave;
 425		} else {
 426			if (!rx_slave || rx_slave->speed < slave->speed)
 427				rx_slave = slave;
 428		}
 429		if (slave == bond_info->rx_slave)
 430			found = true;
 431	}
 432	/* we didn't find anything after the current or we have something
 433	 * better before and up to the current slave
 434	 */
 435	if (!rx_slave || (before && rx_slave->speed < before->speed))
 436		rx_slave = before;
 437
 438	if (rx_slave)
 439		bond_info->rx_slave = rx_slave;
 
 440
 441	return rx_slave;
 442}
 443
 444/* teach the switch the mac of a disabled slave
 445 * on the primary for fault tolerance
 446 *
 447 * Caller must hold bond->curr_slave_lock for write or bond lock for write
 448 */
 449static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
 
 450{
 451	if (!bond->curr_active_slave)
 
 
 452		return;
 453
 454	if (!bond->alb_info.primary_is_promisc) {
 455		if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
 456			bond->alb_info.primary_is_promisc = 1;
 457		else
 458			bond->alb_info.primary_is_promisc = 0;
 459	}
 460
 461	bond->alb_info.rlb_promisc_timeout_counter = 0;
 462
 463	alb_send_learning_packets(bond->curr_active_slave, addr, true);
 464}
 465
 466/* slave being removed should not be active at this point
 467 *
 468 * Caller must hold rtnl.
 469 */
 470static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
 471{
 472	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 473	struct rlb_client_info *rx_hash_table;
 474	u32 index, next_index;
 475
 476	/* clear slave from rx_hashtbl */
 477	_lock_rx_hashtbl_bh(bond);
 478
 479	rx_hash_table = bond_info->rx_hashtbl;
 480	index = bond_info->rx_hashtbl_used_head;
 481	for (; index != RLB_NULL_INDEX; index = next_index) {
 482		next_index = rx_hash_table[index].used_next;
 483		if (rx_hash_table[index].slave == slave) {
 484			struct slave *assigned_slave = rlb_next_rx_slave(bond);
 485
 486			if (assigned_slave) {
 487				rx_hash_table[index].slave = assigned_slave;
 488				if (!ether_addr_equal_64bits(rx_hash_table[index].mac_dst,
 489							     mac_bcast)) {
 490					bond_info->rx_hashtbl[index].ntt = 1;
 491					bond_info->rx_ntt = 1;
 492					/* A slave has been removed from the
 493					 * table because it is either disabled
 494					 * or being released. We must retry the
 495					 * update to avoid clients from not
 496					 * being updated & disconnecting when
 497					 * there is stress
 498					 */
 499					bond_info->rlb_update_retry_counter =
 500						RLB_UPDATE_RETRY;
 501				}
 502			} else {  /* there is no active slave */
 503				rx_hash_table[index].slave = NULL;
 504			}
 505		}
 506	}
 507
 508	_unlock_rx_hashtbl_bh(bond);
 509
 510	write_lock_bh(&bond->curr_slave_lock);
 511
 512	if (slave != bond->curr_active_slave)
 513		rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
 514
 515	write_unlock_bh(&bond->curr_slave_lock);
 516}
 517
 518static void rlb_update_client(struct rlb_client_info *client_info)
 519{
 520	int i;
 521
 522	if (!client_info->slave)
 523		return;
 524
 525	for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
 526		struct sk_buff *skb;
 527
 528		skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
 529				 client_info->ip_dst,
 530				 client_info->slave->dev,
 531				 client_info->ip_src,
 532				 client_info->mac_dst,
 533				 client_info->slave->dev->dev_addr,
 534				 client_info->mac_dst);
 535		if (!skb) {
 536			pr_err("%s: Error: failed to create an ARP packet\n",
 537			       client_info->slave->bond->dev->name);
 
 538			continue;
 539		}
 540
 541		skb->dev = client_info->slave->dev;
 542
 543		if (client_info->vlan_id) {
 544			skb = vlan_put_tag(skb, htons(ETH_P_8021Q), client_info->vlan_id);
 545			if (!skb) {
 546				pr_err("%s: Error: failed to insert VLAN tag\n",
 547				       client_info->slave->bond->dev->name);
 548				continue;
 549			}
 550		}
 551
 552		arp_xmit(skb);
 553	}
 554}
 555
 556/* sends ARP REPLIES that update the clients that need updating */
 557static void rlb_update_rx_clients(struct bonding *bond)
 558{
 559	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 560	struct rlb_client_info *client_info;
 561	u32 hash_index;
 562
 563	_lock_rx_hashtbl_bh(bond);
 564
 565	hash_index = bond_info->rx_hashtbl_used_head;
 566	for (; hash_index != RLB_NULL_INDEX;
 567	     hash_index = client_info->used_next) {
 568		client_info = &(bond_info->rx_hashtbl[hash_index]);
 569		if (client_info->ntt) {
 570			rlb_update_client(client_info);
 571			if (bond_info->rlb_update_retry_counter == 0)
 572				client_info->ntt = 0;
 573		}
 574	}
 575
 576	/* do not update the entries again until this counter is zero so that
 577	 * not to confuse the clients.
 578	 */
 579	bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
 580
 581	_unlock_rx_hashtbl_bh(bond);
 582}
 583
 584/* The slave was assigned a new mac address - update the clients */
 585static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
 586{
 587	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 588	struct rlb_client_info *client_info;
 589	int ntt = 0;
 590	u32 hash_index;
 591
 592	_lock_rx_hashtbl_bh(bond);
 593
 594	hash_index = bond_info->rx_hashtbl_used_head;
 595	for (; hash_index != RLB_NULL_INDEX;
 596	     hash_index = client_info->used_next) {
 597		client_info = &(bond_info->rx_hashtbl[hash_index]);
 598
 599		if ((client_info->slave == slave) &&
 600		    !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 601			client_info->ntt = 1;
 602			ntt = 1;
 603		}
 604	}
 605
 606	/* update the team's flag only after the whole iteration */
 607	if (ntt) {
 608		bond_info->rx_ntt = 1;
 609		/* fasten the change */
 610		bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
 611	}
 612
 613	_unlock_rx_hashtbl_bh(bond);
 614}
 615
 616/* mark all clients using src_ip to be updated */
 617static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
 618{
 619	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 620	struct rlb_client_info *client_info;
 621	u32 hash_index;
 622
 623	_lock_rx_hashtbl(bond);
 624
 625	hash_index = bond_info->rx_hashtbl_used_head;
 626	for (; hash_index != RLB_NULL_INDEX;
 627	     hash_index = client_info->used_next) {
 628		client_info = &(bond_info->rx_hashtbl[hash_index]);
 629
 630		if (!client_info->slave) {
 631			pr_err("%s: Error: found a client with no channel in the client's hash table\n",
 632			       bond->dev->name);
 633			continue;
 634		}
 635		/*update all clients using this src_ip, that are not assigned
 636		 * to the team's address (curr_active_slave) and have a known
 637		 * unicast mac address.
 638		 */
 639		if ((client_info->ip_src == src_ip) &&
 640		    !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
 641					     bond->dev->dev_addr) &&
 642		    !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 643			client_info->ntt = 1;
 644			bond_info->rx_ntt = 1;
 645		}
 646	}
 647
 648	_unlock_rx_hashtbl(bond);
 649}
 650
 651/* Caller must hold both bond and ptr locks for read */
 652static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
 
 653{
 654	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 655	struct arp_pkt *arp = arp_pkt(skb);
 656	struct slave *assigned_slave, *curr_active_slave;
 657	struct rlb_client_info *client_info;
 658	u32 hash_index = 0;
 659
 660	_lock_rx_hashtbl(bond);
 661
 662	curr_active_slave = rcu_dereference(bond->curr_active_slave);
 663
 664	hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
 665	client_info = &(bond_info->rx_hashtbl[hash_index]);
 666
 667	if (client_info->assigned) {
 668		if ((client_info->ip_src == arp->ip_src) &&
 669		    (client_info->ip_dst == arp->ip_dst)) {
 670			/* the entry is already assigned to this client */
 671			if (!ether_addr_equal_64bits(arp->mac_dst, mac_bcast)) {
 672				/* update mac address from arp */
 673				ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 674			}
 675			ether_addr_copy(client_info->mac_src, arp->mac_src);
 676
 677			assigned_slave = client_info->slave;
 678			if (assigned_slave) {
 679				_unlock_rx_hashtbl(bond);
 680				return assigned_slave;
 681			}
 682		} else {
 683			/* the entry is already assigned to some other client,
 684			 * move the old client to primary (curr_active_slave) so
 685			 * that the new client can be assigned to this entry.
 686			 */
 687			if (bond->curr_active_slave &&
 688			    client_info->slave != curr_active_slave) {
 689				client_info->slave = curr_active_slave;
 690				rlb_update_client(client_info);
 691			}
 692		}
 693	}
 694	/* assign a new slave */
 695	assigned_slave = __rlb_next_rx_slave(bond);
 696
 697	if (assigned_slave) {
 698		if (!(client_info->assigned &&
 699		      client_info->ip_src == arp->ip_src)) {
 700			/* ip_src is going to be updated,
 701			 * fix the src hash list
 702			 */
 703			u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
 704						    sizeof(arp->ip_src));
 705			rlb_src_unlink(bond, hash_index);
 706			rlb_src_link(bond, hash_src, hash_index);
 707		}
 708
 709		client_info->ip_src = arp->ip_src;
 710		client_info->ip_dst = arp->ip_dst;
 711		/* arp->mac_dst is broadcast for arp reqeusts.
 712		 * will be updated with clients actual unicast mac address
 713		 * upon receiving an arp reply.
 714		 */
 715		ether_addr_copy(client_info->mac_dst, arp->mac_dst);
 716		ether_addr_copy(client_info->mac_src, arp->mac_src);
 717		client_info->slave = assigned_slave;
 718
 719		if (!ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
 720			client_info->ntt = 1;
 721			bond->alb_info.rx_ntt = 1;
 722		} else {
 723			client_info->ntt = 0;
 724		}
 725
 726		if (vlan_get_tag(skb, &client_info->vlan_id))
 727			client_info->vlan_id = 0;
 728
 729		if (!client_info->assigned) {
 730			u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
 
 731			bond_info->rx_hashtbl_used_head = hash_index;
 732			client_info->used_next = prev_tbl_head;
 733			if (prev_tbl_head != RLB_NULL_INDEX) {
 734				bond_info->rx_hashtbl[prev_tbl_head].used_prev =
 735					hash_index;
 736			}
 737			client_info->assigned = 1;
 738		}
 739	}
 740
 741	_unlock_rx_hashtbl(bond);
 742
 743	return assigned_slave;
 744}
 745
 746/* chooses (and returns) transmit channel for arp reply
 747 * does not choose channel for other arp types since they are
 748 * sent on the curr_active_slave
 749 */
 750static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
 751{
 752	struct arp_pkt *arp = arp_pkt(skb);
 753	struct slave *tx_slave = NULL;
 
 
 
 
 
 
 754
 755	/* Don't modify or load balance ARPs that do not originate locally
 756	 * (e.g.,arrive via a bridge).
 757	 */
 758	if (!bond_slave_has_mac_rcu(bond, arp->mac_src))
 759		return NULL;
 760
 
 
 
 
 
 
 
 
 
 761	if (arp->op_code == htons(ARPOP_REPLY)) {
 762		/* the arp must be sent on the selected
 763		* rx channel
 764		*/
 765		tx_slave = rlb_choose_channel(skb, bond);
 766		if (tx_slave)
 767			ether_addr_copy(arp->mac_src, tx_slave->dev->dev_addr);
 768		pr_debug("Server sent ARP Reply packet\n");
 
 
 769	} else if (arp->op_code == htons(ARPOP_REQUEST)) {
 770		/* Create an entry in the rx_hashtbl for this client as a
 771		 * place holder.
 772		 * When the arp reply is received the entry will be updated
 773		 * with the correct unicast address of the client.
 774		 */
 775		rlb_choose_channel(skb, bond);
 776
 777		/* The ARP reply packets must be delayed so that
 778		 * they can cancel out the influence of the ARP request.
 779		 */
 780		bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
 781
 782		/* arp requests are broadcast and are sent on the primary
 783		 * the arp request will collapse all clients on the subnet to
 784		 * the primary slave. We must register these clients to be
 785		 * updated with their assigned mac.
 786		 */
 787		rlb_req_update_subnet_clients(bond, arp->ip_src);
 788		pr_debug("Server sent ARP Request packet\n");
 
 789	}
 790
 791	return tx_slave;
 792}
 793
 794/* Caller must hold bond lock for read */
 795static void rlb_rebalance(struct bonding *bond)
 796{
 797	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 798	struct slave *assigned_slave;
 799	struct rlb_client_info *client_info;
 800	int ntt;
 801	u32 hash_index;
 802
 803	_lock_rx_hashtbl_bh(bond);
 804
 805	ntt = 0;
 806	hash_index = bond_info->rx_hashtbl_used_head;
 807	for (; hash_index != RLB_NULL_INDEX;
 808	     hash_index = client_info->used_next) {
 809		client_info = &(bond_info->rx_hashtbl[hash_index]);
 810		assigned_slave = __rlb_next_rx_slave(bond);
 811		if (assigned_slave && (client_info->slave != assigned_slave)) {
 812			client_info->slave = assigned_slave;
 813			client_info->ntt = 1;
 814			ntt = 1;
 
 
 815		}
 816	}
 817
 818	/* update the team's flag only after the whole iteration */
 819	if (ntt)
 820		bond_info->rx_ntt = 1;
 821	_unlock_rx_hashtbl_bh(bond);
 822}
 823
 824/* Caller must hold rx_hashtbl lock */
 825static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
 826{
 827	entry->used_next = RLB_NULL_INDEX;
 828	entry->used_prev = RLB_NULL_INDEX;
 829	entry->assigned = 0;
 830	entry->slave = NULL;
 831	entry->vlan_id = 0;
 832}
 833static void rlb_init_table_entry_src(struct rlb_client_info *entry)
 834{
 835	entry->src_first = RLB_NULL_INDEX;
 836	entry->src_prev = RLB_NULL_INDEX;
 837	entry->src_next = RLB_NULL_INDEX;
 838}
 839
 840static void rlb_init_table_entry(struct rlb_client_info *entry)
 841{
 842	memset(entry, 0, sizeof(struct rlb_client_info));
 843	rlb_init_table_entry_dst(entry);
 844	rlb_init_table_entry_src(entry);
 845}
 846
 847static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
 848{
 849	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 850	u32 next_index = bond_info->rx_hashtbl[index].used_next;
 851	u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
 852
 853	if (index == bond_info->rx_hashtbl_used_head)
 854		bond_info->rx_hashtbl_used_head = next_index;
 855	if (prev_index != RLB_NULL_INDEX)
 856		bond_info->rx_hashtbl[prev_index].used_next = next_index;
 857	if (next_index != RLB_NULL_INDEX)
 858		bond_info->rx_hashtbl[next_index].used_prev = prev_index;
 859}
 860
 861/* unlink a rlb hash table entry from the src list */
 862static void rlb_src_unlink(struct bonding *bond, u32 index)
 863{
 864	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 865	u32 next_index = bond_info->rx_hashtbl[index].src_next;
 866	u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
 867
 868	bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
 869	bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
 870
 871	if (next_index != RLB_NULL_INDEX)
 872		bond_info->rx_hashtbl[next_index].src_prev = prev_index;
 873
 874	if (prev_index == RLB_NULL_INDEX)
 875		return;
 876
 877	/* is prev_index pointing to the head of this list? */
 878	if (bond_info->rx_hashtbl[prev_index].src_first == index)
 879		bond_info->rx_hashtbl[prev_index].src_first = next_index;
 880	else
 881		bond_info->rx_hashtbl[prev_index].src_next = next_index;
 882
 883}
 884
 885static void rlb_delete_table_entry(struct bonding *bond, u32 index)
 886{
 887	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 888	struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 889
 890	rlb_delete_table_entry_dst(bond, index);
 891	rlb_init_table_entry_dst(entry);
 892
 893	rlb_src_unlink(bond, index);
 894}
 895
 896/* add the rx_hashtbl[ip_dst_hash] entry to the list
 897 * of entries with identical ip_src_hash
 898 */
 899static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
 900{
 901	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 902	u32 next;
 903
 904	bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
 905	next = bond_info->rx_hashtbl[ip_src_hash].src_first;
 906	bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
 907	if (next != RLB_NULL_INDEX)
 908		bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
 909	bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
 910}
 911
 912/* deletes all rx_hashtbl entries with  arp->ip_src if their mac_src does
 913 * not match arp->mac_src */
 
 914static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
 915{
 916	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 917	u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
 918	u32 index;
 919
 920	_lock_rx_hashtbl_bh(bond);
 921
 922	index = bond_info->rx_hashtbl[ip_src_hash].src_first;
 923	while (index != RLB_NULL_INDEX) {
 924		struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
 925		u32 next_index = entry->src_next;
 
 926		if (entry->ip_src == arp->ip_src &&
 927		    !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
 928				rlb_delete_table_entry(bond, index);
 929		index = next_index;
 930	}
 931	_unlock_rx_hashtbl_bh(bond);
 932}
 933
 934static int rlb_initialize(struct bonding *bond)
 935{
 936	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 937	struct rlb_client_info	*new_hashtbl;
 938	int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
 939	int i;
 940
 941	new_hashtbl = kmalloc(size, GFP_KERNEL);
 942	if (!new_hashtbl)
 943		return -1;
 944
 945	_lock_rx_hashtbl_bh(bond);
 946
 947	bond_info->rx_hashtbl = new_hashtbl;
 948
 949	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 950
 951	for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
 952		rlb_init_table_entry(bond_info->rx_hashtbl + i);
 953
 954	_unlock_rx_hashtbl_bh(bond);
 955
 956	/* register to receive ARPs */
 957	bond->recv_probe = rlb_arp_recv;
 958
 959	return 0;
 960}
 961
 962static void rlb_deinitialize(struct bonding *bond)
 963{
 964	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 965
 966	_lock_rx_hashtbl_bh(bond);
 967
 968	kfree(bond_info->rx_hashtbl);
 969	bond_info->rx_hashtbl = NULL;
 970	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
 971
 972	_unlock_rx_hashtbl_bh(bond);
 973}
 974
 975static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
 976{
 977	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 978	u32 curr_index;
 979
 980	_lock_rx_hashtbl_bh(bond);
 981
 982	curr_index = bond_info->rx_hashtbl_used_head;
 983	while (curr_index != RLB_NULL_INDEX) {
 984		struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
 985		u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
 986
 987		if (curr->vlan_id == vlan_id)
 988			rlb_delete_table_entry(bond, curr_index);
 989
 990		curr_index = next_index;
 991	}
 992
 993	_unlock_rx_hashtbl_bh(bond);
 994}
 995
 996/*********************** tlb/rlb shared functions *********************/
 997
 998static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
 999			    __be16 vlan_proto, u16 vid)
1000{
1001	struct learning_pkt pkt;
1002	struct sk_buff *skb;
1003	int size = sizeof(struct learning_pkt);
1004	char *data;
1005
1006	memset(&pkt, 0, size);
1007	ether_addr_copy(pkt.mac_dst, mac_addr);
1008	ether_addr_copy(pkt.mac_src, mac_addr);
1009	pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
1010
1011	skb = dev_alloc_skb(size);
1012	if (!skb)
1013		return;
1014
1015	data = skb_put(skb, size);
1016	memcpy(data, &pkt, size);
1017
1018	skb_reset_mac_header(skb);
1019	skb->network_header = skb->mac_header + ETH_HLEN;
1020	skb->protocol = pkt.type;
1021	skb->priority = TC_PRIO_CONTROL;
1022	skb->dev = slave->dev;
1023
1024	if (vid) {
1025		skb = vlan_put_tag(skb, vlan_proto, vid);
1026		if (!skb) {
1027			pr_err("%s: Error: failed to insert VLAN tag\n",
1028			       slave->bond->dev->name);
1029			return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1030		}
1031	}
1032
1033	dev_queue_xmit(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
1034}
1035
1036static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
1037				      bool strict_match)
1038{
1039	struct bonding *bond = bond_get_bond_by_slave(slave);
1040	struct net_device *upper;
1041	struct list_head *iter;
 
 
 
 
 
1042
 
1043	/* send untagged */
1044	alb_send_lp_vid(slave, mac_addr, 0, 0);
1045
1046	/* loop through vlans and send one packet for each */
 
 
1047	rcu_read_lock();
1048	netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
1049		if (is_vlan_dev(upper) && vlan_get_encap_level(upper) == 0) {
1050			if (strict_match &&
1051			    ether_addr_equal_64bits(mac_addr,
1052						    upper->dev_addr)) {
1053				alb_send_lp_vid(slave, mac_addr,
1054						vlan_dev_vlan_proto(upper),
1055						vlan_dev_vlan_id(upper));
1056			} else if (!strict_match) {
1057				alb_send_lp_vid(slave, upper->dev_addr,
1058						vlan_dev_vlan_proto(upper),
1059						vlan_dev_vlan_id(upper));
1060			}
1061		}
1062	}
1063	rcu_read_unlock();
1064}
1065
1066static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
 
1067{
1068	struct net_device *dev = slave->dev;
1069	struct sockaddr s_addr;
1070
1071	if (slave->bond->params.mode == BOND_MODE_TLB) {
1072		memcpy(dev->dev_addr, addr, dev->addr_len);
1073		return 0;
1074	}
1075
1076	/* for rlb each slave must have a unique hw mac addresses so that */
1077	/* each slave will receive packets destined to a different mac */
1078	memcpy(s_addr.sa_data, addr, dev->addr_len);
1079	s_addr.sa_family = dev->type;
1080	if (dev_set_mac_address(dev, &s_addr)) {
1081		pr_err("%s: Error: dev_set_mac_address of dev %s failed!\n"
1082		       "ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
1083		       slave->bond->dev->name, dev->name);
1084		return -EOPNOTSUPP;
1085	}
1086	return 0;
1087}
1088
1089/*
1090 * Swap MAC addresses between two slaves.
1091 *
1092 * Called with RTNL held, and no other locks.
1093 *
1094 */
1095
1096static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1097{
1098	u8 tmp_mac_addr[ETH_ALEN];
1099
1100	ether_addr_copy(tmp_mac_addr, slave1->dev->dev_addr);
1101	alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
1102	alb_set_slave_mac_addr(slave2, tmp_mac_addr);
 
 
 
1103
1104}
1105
1106/*
1107 * Send learning packets after MAC address swap.
1108 *
1109 * Called with RTNL and no other locks
1110 */
1111static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1112				struct slave *slave2)
1113{
1114	int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
1115	struct slave *disabled_slave = NULL;
1116
1117	ASSERT_RTNL();
1118
1119	/* fasten the change in the switch */
1120	if (SLAVE_IS_OK(slave1)) {
1121		alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1122		if (bond->alb_info.rlb_enabled) {
1123			/* inform the clients that the mac address
1124			 * has changed
1125			 */
1126			rlb_req_update_slave_clients(bond, slave1);
1127		}
1128	} else {
1129		disabled_slave = slave1;
1130	}
1131
1132	if (SLAVE_IS_OK(slave2)) {
1133		alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1134		if (bond->alb_info.rlb_enabled) {
1135			/* inform the clients that the mac address
1136			 * has changed
1137			 */
1138			rlb_req_update_slave_clients(bond, slave2);
1139		}
1140	} else {
1141		disabled_slave = slave2;
1142	}
1143
1144	if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1145		/* A disabled slave was assigned an active mac addr */
1146		rlb_teach_disabled_mac_on_primary(bond,
1147						  disabled_slave->dev->dev_addr);
1148	}
1149}
1150
1151/**
1152 * alb_change_hw_addr_on_detach
1153 * @bond: bonding we're working on
1154 * @slave: the slave that was just detached
1155 *
1156 * We assume that @slave was already detached from the slave list.
1157 *
1158 * If @slave's permanent hw address is different both from its current
1159 * address and from @bond's address, then somewhere in the bond there's
1160 * a slave that has @slave's permanet address as its current address.
1161 * We'll make sure that that slave no longer uses @slave's permanent address.
1162 *
1163 * Caller must hold RTNL and no other locks
1164 */
1165static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1166{
1167	int perm_curr_diff;
1168	int perm_bond_diff;
1169	struct slave *found_slave;
1170
1171	perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1172						  slave->dev->dev_addr);
1173	perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1174						  bond->dev->dev_addr);
1175
1176	if (perm_curr_diff && perm_bond_diff) {
1177		found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1178
1179		if (found_slave) {
1180			/* locking: needs RTNL and nothing else */
1181			alb_swap_mac_addr(slave, found_slave);
1182			alb_fasten_mac_swap(bond, slave, found_slave);
1183		}
1184	}
1185}
1186
1187/**
1188 * alb_handle_addr_collision_on_attach
1189 * @bond: bonding we're working on
1190 * @slave: the slave that was just attached
1191 *
1192 * checks uniqueness of slave's mac address and handles the case the
1193 * new slave uses the bonds mac address.
1194 *
1195 * If the permanent hw address of @slave is @bond's hw address, we need to
1196 * find a different hw address to give @slave, that isn't in use by any other
1197 * slave in the bond. This address must be, of course, one of the permanent
1198 * addresses of the other slaves.
1199 *
1200 * We go over the slave list, and for each slave there we compare its
1201 * permanent hw address with the current address of all the other slaves.
1202 * If no match was found, then we've found a slave with a permanent address
1203 * that isn't used by any other slave in the bond, so we can assign it to
1204 * @slave.
1205 *
1206 * assumption: this function is called before @slave is attached to the
1207 *	       bond slave list.
1208 */
1209static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1210{
1211	struct slave *has_bond_addr = bond->curr_active_slave;
1212	struct slave *tmp_slave1, *free_mac_slave = NULL;
1213	struct list_head *iter;
1214
1215	if (!bond_has_slaves(bond)) {
1216		/* this is the first slave */
1217		return 0;
1218	}
1219
1220	/* if slave's mac address differs from bond's mac address
1221	 * check uniqueness of slave's mac address against the other
1222	 * slaves in the bond.
1223	 */
1224	if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1225		if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1226			return 0;
1227
1228		/* Try setting slave mac to bond address and fall-through
1229		   to code handling that situation below... */
1230		alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
 
 
1231	}
1232
1233	/* The slave's address is equal to the address of the bond.
1234	 * Search for a spare address in the bond for this slave.
1235	 */
1236	bond_for_each_slave(bond, tmp_slave1, iter) {
1237		if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1238			/* no slave has tmp_slave1's perm addr
1239			 * as its curr addr
1240			 */
1241			free_mac_slave = tmp_slave1;
1242			break;
1243		}
1244
1245		if (!has_bond_addr) {
1246			if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1247						    bond->dev->dev_addr)) {
1248
1249				has_bond_addr = tmp_slave1;
1250			}
1251		}
1252	}
1253
1254	if (free_mac_slave) {
1255		alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
 
1256
1257		pr_warn("%s: Warning: the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1258			bond->dev->name, slave->dev->name,
1259			free_mac_slave->dev->name);
1260
1261	} else if (has_bond_addr) {
1262		pr_err("%s: Error: the hw address of slave %s is in use by the bond; couldn't find a slave with a free hw address to give it (this should not have happened)\n",
1263		       bond->dev->name, slave->dev->name);
1264		return -EFAULT;
1265	}
1266
1267	return 0;
1268}
1269
1270/**
1271 * alb_set_mac_address
1272 * @bond:
1273 * @addr:
1274 *
1275 * In TLB mode all slaves are configured to the bond's hw address, but set
1276 * their dev_addr field to different addresses (based on their permanent hw
1277 * addresses).
1278 *
1279 * For each slave, this function sets the interface to the new address and then
1280 * changes its dev_addr field to its previous value.
1281 *
1282 * Unwinding assumes bond's mac address has not yet changed.
1283 */
1284static int alb_set_mac_address(struct bonding *bond, void *addr)
1285{
1286	struct slave *slave, *rollback_slave;
1287	struct list_head *iter;
1288	struct sockaddr sa;
1289	char tmp_addr[ETH_ALEN];
1290	int res;
1291
1292	if (bond->alb_info.rlb_enabled)
1293		return 0;
1294
1295	bond_for_each_slave(bond, slave, iter) {
1296		/* save net_device's current hw address */
1297		ether_addr_copy(tmp_addr, slave->dev->dev_addr);
 
1298
1299		res = dev_set_mac_address(slave->dev, addr);
1300
1301		/* restore net_device's hw address */
1302		ether_addr_copy(slave->dev->dev_addr, tmp_addr);
1303
1304		if (res)
1305			goto unwind;
1306	}
1307
1308	return 0;
1309
1310unwind:
1311	memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1312	sa.sa_family = bond->dev->type;
1313
1314	/* unwind from head to the slave that failed */
1315	bond_for_each_slave(bond, rollback_slave, iter) {
1316		if (rollback_slave == slave)
1317			break;
1318		ether_addr_copy(tmp_addr, rollback_slave->dev->dev_addr);
1319		dev_set_mac_address(rollback_slave->dev, &sa);
1320		ether_addr_copy(rollback_slave->dev->dev_addr, tmp_addr);
 
 
1321	}
1322
1323	return res;
1324}
1325
1326/************************ exported alb funcions ************************/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1327
1328int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1329{
1330	int res;
1331
1332	res = tlb_initialize(bond);
1333	if (res)
1334		return res;
1335
1336	if (rlb_enabled) {
1337		bond->alb_info.rlb_enabled = 1;
1338		/* initialize rlb */
1339		res = rlb_initialize(bond);
1340		if (res) {
1341			tlb_deinitialize(bond);
1342			return res;
1343		}
 
1344	} else {
1345		bond->alb_info.rlb_enabled = 0;
1346	}
1347
1348	return 0;
1349}
1350
1351void bond_alb_deinitialize(struct bonding *bond)
1352{
1353	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1354
1355	tlb_deinitialize(bond);
1356
1357	if (bond_info->rlb_enabled)
1358		rlb_deinitialize(bond);
1359}
1360
1361int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
 
1362{
1363	struct bonding *bond = netdev_priv(bond_dev);
1364	struct ethhdr *eth_data;
1365	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1366	struct slave *tx_slave = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1367	static const __be32 ip_bcast = htonl(0xffffffff);
1368	int hash_size = 0;
1369	int do_tx_balance = 1;
1370	u32 hash_index = 0;
1371	const u8 *hash_start = NULL;
1372	struct ipv6hdr *ip6hdr;
 
 
 
1373
1374	skb_reset_mac_header(skb);
1375	eth_data = eth_hdr(skb);
1376
1377	switch (ntohs(skb->protocol)) {
1378	case ETH_P_IP: {
1379		const struct iphdr *iph = ip_hdr(skb);
1380
1381		if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast) ||
1382		    (iph->daddr == ip_bcast) ||
1383		    (iph->protocol == IPPROTO_IGMP)) {
1384			do_tx_balance = 0;
 
 
 
 
1385			break;
1386		}
1387		hash_start = (char *)&(iph->daddr);
1388		hash_size = sizeof(iph->daddr);
1389	}
1390		break;
1391	case ETH_P_IPV6:
 
 
 
1392		/* IPv6 doesn't really use broadcast mac address, but leave
1393		 * that here just in case.
1394		 */
1395		if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast)) {
1396			do_tx_balance = 0;
1397			break;
1398		}
1399
1400		/* IPv6 uses all-nodes multicast as an equivalent to
1401		 * broadcasts in IPv4.
1402		 */
1403		if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1404			do_tx_balance = 0;
 
 
 
 
 
1405			break;
1406		}
1407
1408		/* Additianally, DAD probes should not be tx-balanced as that
 
1409		 * will lead to false positives for duplicate addresses and
1410		 * prevent address configuration from working.
1411		 */
1412		ip6hdr = ipv6_hdr(skb);
1413		if (ipv6_addr_any(&ip6hdr->saddr)) {
1414			do_tx_balance = 0;
1415			break;
1416		}
1417
1418		hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1419		hash_size = sizeof(ipv6_hdr(skb)->daddr);
1420		break;
1421	case ETH_P_IPX:
1422		if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1423			/* something is wrong with this packet */
1424			do_tx_balance = 0;
1425			break;
1426		}
1427
1428		if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1429			/* The only protocol worth balancing in
1430			 * this family since it has an "ARP" like
1431			 * mechanism
1432			 */
1433			do_tx_balance = 0;
1434			break;
1435		}
1436
1437		hash_start = (char *)eth_data->h_dest;
1438		hash_size = ETH_ALEN;
1439		break;
 
1440	case ETH_P_ARP:
1441		do_tx_balance = 0;
1442		if (bond_info->rlb_enabled)
1443			tx_slave = rlb_arp_xmit(skb, bond);
1444		break;
1445	default:
1446		do_tx_balance = 0;
1447		break;
1448	}
1449
1450	if (do_tx_balance) {
1451		hash_index = _simple_hash(hash_start, hash_size);
1452		tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1453	}
 
 
 
 
 
1454
1455	if (!tx_slave) {
1456		/* unbalanced or unassigned, send through primary */
1457		tx_slave = rcu_dereference(bond->curr_active_slave);
1458		bond_info->unbalanced_load += skb->len;
1459	}
1460
1461	if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1462		if (tx_slave != rcu_dereference(bond->curr_active_slave)) {
1463			ether_addr_copy(eth_data->h_source,
1464					tx_slave->dev->dev_addr);
 
1465		}
1466
1467		bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1468		goto out;
1469	}
 
 
1470
1471	if (tx_slave) {
1472		_lock_tx_hashtbl(bond);
1473		__tlb_clear_slave(bond, tx_slave, 0);
1474		_unlock_tx_hashtbl(bond);
1475	}
1476
1477	/* no suitable interface, frame not sent */
1478	dev_kfree_skb_any(skb);
1479out:
1480	return NETDEV_TX_OK;
1481}
1482
1483void bond_alb_monitor(struct work_struct *work)
1484{
1485	struct bonding *bond = container_of(work, struct bonding,
1486					    alb_work.work);
1487	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1488	struct list_head *iter;
1489	struct slave *slave;
1490
1491	if (!bond_has_slaves(bond)) {
1492		bond_info->tx_rebalance_counter = 0;
1493		bond_info->lp_counter = 0;
1494		goto re_arm;
1495	}
1496
1497	rcu_read_lock();
1498
1499	bond_info->tx_rebalance_counter++;
1500	bond_info->lp_counter++;
1501
1502	/* send learning packets */
1503	if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1504		bool strict_match;
1505
1506		/* change of curr_active_slave involves swapping of mac addresses.
1507		 * in order to avoid this swapping from happening while
1508		 * sending the learning packets, the curr_slave_lock must be held for
1509		 * read.
1510		 */
1511		read_lock(&bond->curr_slave_lock);
1512
1513		bond_for_each_slave_rcu(bond, slave, iter) {
1514			/* If updating current_active, use all currently
1515			 * user mac addreses (!strict_match).  Otherwise, only
1516			 * use mac of the slave device.
 
1517			 */
1518			strict_match = (slave != bond->curr_active_slave);
 
1519			alb_send_learning_packets(slave, slave->dev->dev_addr,
1520						  strict_match);
1521		}
1522
1523		read_unlock(&bond->curr_slave_lock);
1524
1525		bond_info->lp_counter = 0;
1526	}
1527
1528	/* rebalance tx traffic */
1529	if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1530
1531		read_lock(&bond->curr_slave_lock);
1532
1533		bond_for_each_slave_rcu(bond, slave, iter) {
1534			tlb_clear_slave(bond, slave, 1);
1535			if (slave == bond->curr_active_slave) {
1536				SLAVE_TLB_INFO(slave).load =
1537					bond_info->unbalanced_load /
1538						BOND_TLB_REBALANCE_INTERVAL;
1539				bond_info->unbalanced_load = 0;
1540			}
1541		}
1542
1543		read_unlock(&bond->curr_slave_lock);
1544
1545		bond_info->tx_rebalance_counter = 0;
1546	}
1547
1548	/* handle rlb stuff */
1549	if (bond_info->rlb_enabled) {
1550		if (bond_info->primary_is_promisc &&
1551		    (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1552
1553			/*
1554			 * dev_set_promiscuity requires rtnl and
1555			 * nothing else.  Avoid race with bond_close.
1556			 */
1557			rcu_read_unlock();
1558			if (!rtnl_trylock())
1559				goto re_arm;
1560
1561			bond_info->rlb_promisc_timeout_counter = 0;
1562
1563			/* If the primary was set to promiscuous mode
1564			 * because a slave was disabled then
1565			 * it can now leave promiscuous mode.
1566			 */
1567			dev_set_promiscuity(bond->curr_active_slave->dev, -1);
 
1568			bond_info->primary_is_promisc = 0;
1569
1570			rtnl_unlock();
1571			rcu_read_lock();
1572		}
1573
1574		if (bond_info->rlb_rebalance) {
1575			bond_info->rlb_rebalance = 0;
1576			rlb_rebalance(bond);
1577		}
1578
1579		/* check if clients need updating */
1580		if (bond_info->rx_ntt) {
1581			if (bond_info->rlb_update_delay_counter) {
1582				--bond_info->rlb_update_delay_counter;
1583			} else {
1584				rlb_update_rx_clients(bond);
1585				if (bond_info->rlb_update_retry_counter)
1586					--bond_info->rlb_update_retry_counter;
1587				else
1588					bond_info->rx_ntt = 0;
1589			}
1590		}
1591	}
1592	rcu_read_unlock();
1593re_arm:
1594	queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1595}
1596
1597/* assumption: called before the slave is attached to the bond
1598 * and not locked by the bond lock
1599 */
1600int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1601{
1602	int res;
1603
1604	res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
 
1605	if (res)
1606		return res;
1607
1608	res = alb_handle_addr_collision_on_attach(bond, slave);
1609	if (res)
1610		return res;
1611
1612	tlb_init_slave(slave);
1613
1614	/* order a rebalance ASAP */
1615	bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
 
1616
1617	if (bond->alb_info.rlb_enabled)
1618		bond->alb_info.rlb_rebalance = 1;
1619
1620	return 0;
1621}
1622
1623/*
1624 * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1625 * if necessary.
1626 *
1627 * Caller must hold RTNL and no other locks
1628 */
1629void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1630{
1631	if (bond_has_slaves(bond))
1632		alb_change_hw_addr_on_detach(bond, slave);
1633
1634	tlb_clear_slave(bond, slave, 0);
1635
1636	if (bond->alb_info.rlb_enabled) {
1637		bond->alb_info.rx_slave = NULL;
1638		rlb_clear_slave(bond, slave);
1639	}
 
1640}
1641
1642/* Caller must hold bond lock for read */
1643void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1644{
1645	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1646
1647	if (link == BOND_LINK_DOWN) {
1648		tlb_clear_slave(bond, slave, 0);
1649		if (bond->alb_info.rlb_enabled)
1650			rlb_clear_slave(bond, slave);
1651	} else if (link == BOND_LINK_UP) {
1652		/* order a rebalance ASAP */
1653		bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
 
1654		if (bond->alb_info.rlb_enabled) {
1655			bond->alb_info.rlb_rebalance = 1;
1656			/* If the updelay module parameter is smaller than the
1657			 * forwarding delay of the switch the rebalance will
1658			 * not work because the rebalance arp replies will
1659			 * not be forwarded to the clients..
1660			 */
1661		}
1662	}
 
 
 
 
 
1663}
1664
1665/**
1666 * bond_alb_handle_active_change - assign new curr_active_slave
1667 * @bond: our bonding struct
1668 * @new_slave: new slave to assign
1669 *
1670 * Set the bond->curr_active_slave to @new_slave and handle
1671 * mac address swapping and promiscuity changes as needed.
1672 *
1673 * If new_slave is NULL, caller must hold curr_slave_lock or
1674 * bond->lock for write.
1675 *
1676 * If new_slave is not NULL, caller must hold RTNL, curr_slave_lock
1677 * for write.  Processing here may sleep, so no other locks may be held.
1678 */
1679void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1680	__releases(&bond->curr_slave_lock)
1681	__acquires(&bond->curr_slave_lock)
1682{
1683	struct slave *swap_slave;
 
1684
1685	if (bond->curr_active_slave == new_slave)
 
1686		return;
1687
1688	if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1689		dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1690		bond->alb_info.primary_is_promisc = 0;
1691		bond->alb_info.rlb_promisc_timeout_counter = 0;
1692	}
1693
1694	swap_slave = bond->curr_active_slave;
1695	rcu_assign_pointer(bond->curr_active_slave, new_slave);
1696
1697	if (!new_slave || !bond_has_slaves(bond))
1698		return;
1699
1700	/* set the new curr_active_slave to the bonds mac address
1701	 * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1702	 */
1703	if (!swap_slave)
1704		swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1705
1706	/*
1707	 * Arrange for swap_slave and new_slave to temporarily be
1708	 * ignored so we can mess with their MAC addresses without
1709	 * fear of interference from transmit activity.
1710	 */
1711	if (swap_slave)
1712		tlb_clear_slave(bond, swap_slave, 1);
1713	tlb_clear_slave(bond, new_slave, 1);
1714
1715	write_unlock_bh(&bond->curr_slave_lock);
1716
1717	ASSERT_RTNL();
1718
1719	/* in TLB mode, the slave might flip down/up with the old dev_addr,
1720	 * and thus filter bond->dev_addr's packets, so force bond's mac
1721	 */
1722	if (bond->params.mode == BOND_MODE_TLB) {
1723		struct sockaddr sa;
1724		u8 tmp_addr[ETH_ALEN];
1725
1726		ether_addr_copy(tmp_addr, new_slave->dev->dev_addr);
1727
1728		memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1729		sa.sa_family = bond->dev->type;
 
 
1730		/* we don't care if it can't change its mac, best effort */
1731		dev_set_mac_address(new_slave->dev, &sa);
 
1732
1733		ether_addr_copy(new_slave->dev->dev_addr, tmp_addr);
1734	}
1735
1736	/* curr_active_slave must be set before calling alb_swap_mac_addr */
1737	if (swap_slave) {
1738		/* swap mac address */
1739		alb_swap_mac_addr(swap_slave, new_slave);
1740		alb_fasten_mac_swap(bond, swap_slave, new_slave);
1741	} else {
1742		/* set the new_slave to the bond mac address */
1743		alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
 
1744		alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1745					  false);
1746	}
1747
1748	write_lock_bh(&bond->curr_slave_lock);
1749}
1750
1751/*
1752 * Called with RTNL
1753 */
1754int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1755	__acquires(&bond->lock)
1756	__releases(&bond->lock)
1757{
1758	struct bonding *bond = netdev_priv(bond_dev);
1759	struct sockaddr *sa = addr;
 
1760	struct slave *swap_slave;
1761	int res;
1762
1763	if (!is_valid_ether_addr(sa->sa_data))
1764		return -EADDRNOTAVAIL;
1765
1766	res = alb_set_mac_address(bond, addr);
1767	if (res)
1768		return res;
1769
1770	memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1771
1772	/* If there is no curr_active_slave there is nothing else to do.
1773	 * Otherwise we'll need to pass the new address to it and handle
1774	 * duplications.
1775	 */
1776	if (!bond->curr_active_slave)
 
1777		return 0;
1778
1779	swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1780
1781	if (swap_slave) {
1782		alb_swap_mac_addr(swap_slave, bond->curr_active_slave);
1783		alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1784	} else {
1785		alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr);
 
1786
1787		read_lock(&bond->lock);
1788		alb_send_learning_packets(bond->curr_active_slave,
1789					  bond_dev->dev_addr, false);
1790		if (bond->alb_info.rlb_enabled) {
1791			/* inform clients mac address has changed */
1792			rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1793		}
1794		read_unlock(&bond->lock);
1795	}
1796
1797	return 0;
1798}
1799
1800void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1801{
1802	if (bond->alb_info.rlb_enabled)
1803		rlb_clear_vlan(bond, vlan_id);
1804}
1805