1/*
2 * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, see <http://www.gnu.org/licenses/>.
16 *
17 * The full GNU General Public License is included in this distribution in the
18 * file called LICENSE.
19 *
20 */
21
22#include <linux/skbuff.h>
23#include <linux/netdevice.h>
24#include <linux/etherdevice.h>
25#include <linux/pkt_sched.h>
26#include <linux/spinlock.h>
27#include <linux/slab.h>
28#include <linux/timer.h>
29#include <linux/ip.h>
30#include <linux/ipv6.h>
31#include <linux/if_arp.h>
32#include <linux/if_ether.h>
33#include <linux/if_bonding.h>
34#include <linux/if_vlan.h>
35#include <linux/in.h>
36#include <net/ipx.h>
37#include <net/arp.h>
38#include <net/ipv6.h>
39#include <asm/byteorder.h>
40#include <net/bonding.h>
41#include <net/bond_alb.h>
42
43
44
45#ifndef __long_aligned
46#define __long_aligned __attribute__((aligned((sizeof(long)))))
47#endif
48static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
49	0xff, 0xff, 0xff, 0xff, 0xff, 0xff
50};
51static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
52	0x33, 0x33, 0x00, 0x00, 0x00, 0x01
53};
54static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
55
56#pragma pack(1)
57struct learning_pkt {
58	u8 mac_dst[ETH_ALEN];
59	u8 mac_src[ETH_ALEN];
60	__be16 type;
61	u8 padding[ETH_ZLEN - ETH_HLEN];
62};
63
64struct arp_pkt {
65	__be16  hw_addr_space;
66	__be16  prot_addr_space;
67	u8      hw_addr_len;
68	u8      prot_addr_len;
69	__be16  op_code;
70	u8      mac_src[ETH_ALEN];	/* sender hardware address */
71	__be32  ip_src;			/* sender IP address */
72	u8      mac_dst[ETH_ALEN];	/* target hardware address */
73	__be32  ip_dst;			/* target IP address */
74};
75#pragma pack()
76
77static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
78{
79	return (struct arp_pkt *)skb_network_header(skb);
80}
81
82/* Forward declaration */
83static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
84				      bool strict_match);
85static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
86static void rlb_src_unlink(struct bonding *bond, u32 index);
87static void rlb_src_link(struct bonding *bond, u32 ip_src_hash,
88			 u32 ip_dst_hash);
89
90static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
91{
92	int i;
93	u8 hash = 0;
94
95	for (i = 0; i < hash_size; i++)
96		hash ^= hash_start[i];
97
98	return hash;
99}
100
101/*********************** tlb specific functions ***************************/
102
103static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
104{
105	if (save_load) {
106		entry->load_history = 1 + entry->tx_bytes /
107				      BOND_TLB_REBALANCE_INTERVAL;
108		entry->tx_bytes = 0;
109	}
110
111	entry->tx_slave = NULL;
112	entry->next = TLB_NULL_INDEX;
113	entry->prev = TLB_NULL_INDEX;
114}
115
116static inline void tlb_init_slave(struct slave *slave)
117{
118	SLAVE_TLB_INFO(slave).load = 0;
119	SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
120}
121
122static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
123			 int save_load)
124{
125	struct tlb_client_info *tx_hash_table;
126	u32 index;
127
128	/* clear slave from tx_hashtbl */
129	tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
130
131	/* skip this if we've already freed the tx hash table */
132	if (tx_hash_table) {
133		index = SLAVE_TLB_INFO(slave).head;
134		while (index != TLB_NULL_INDEX) {
135			u32 next_index = tx_hash_table[index].next;
136			tlb_init_table_entry(&tx_hash_table[index], save_load);
137			index = next_index;
138		}
139	}
140
141	tlb_init_slave(slave);
142}
143
144static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
145			 int save_load)
146{
147	spin_lock_bh(&bond->mode_lock);
148	__tlb_clear_slave(bond, slave, save_load);
149	spin_unlock_bh(&bond->mode_lock);
150}
151
152/* Must be called before starting the monitor timer */
153static int tlb_initialize(struct bonding *bond)
154{
155	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
156	int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
157	struct tlb_client_info *new_hashtbl;
158	int i;
159
160	new_hashtbl = kzalloc(size, GFP_KERNEL);
161	if (!new_hashtbl)
162		return -1;
163
164	spin_lock_bh(&bond->mode_lock);
165
166	bond_info->tx_hashtbl = new_hashtbl;
167
168	for (i = 0; i < TLB_HASH_TABLE_SIZE; i++)
169		tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
170
171	spin_unlock_bh(&bond->mode_lock);
172
173	return 0;
174}
175
176/* Must be called only after all slaves have been released */
177static void tlb_deinitialize(struct bonding *bond)
178{
179	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
180
181	spin_lock_bh(&bond->mode_lock);
182
183	kfree(bond_info->tx_hashtbl);
184	bond_info->tx_hashtbl = NULL;
185
186	spin_unlock_bh(&bond->mode_lock);
187}
188
189static long long compute_gap(struct slave *slave)
190{
191	return (s64) (slave->speed << 20) - /* Convert to Megabit per sec */
192	       (s64) (SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
193}
194
195static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
196{
197	struct slave *slave, *least_loaded;
198	struct list_head *iter;
199	long long max_gap;
200
201	least_loaded = NULL;
202	max_gap = LLONG_MIN;
203
204	/* Find the slave with the largest gap */
205	bond_for_each_slave_rcu(bond, slave, iter) {
206		if (bond_slave_can_tx(slave)) {
207			long long gap = compute_gap(slave);
208
209			if (max_gap < gap) {
210				least_loaded = slave;
211				max_gap = gap;
212			}
213		}
214	}
215
216	return least_loaded;
217}
218
219static struct slave *__tlb_choose_channel(struct bonding *bond, u32 hash_index,
220						u32 skb_len)
221{
222	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
223	struct tlb_client_info *hash_table;
224	struct slave *assigned_slave;
225
226	hash_table = bond_info->tx_hashtbl;
227	assigned_slave = hash_table[hash_index].tx_slave;
228	if (!assigned_slave) {
229		assigned_slave = tlb_get_least_loaded_slave(bond);
230
231		if (assigned_slave) {
232			struct tlb_slave_info *slave_info =
233				&(SLAVE_TLB_INFO(assigned_slave));
234			u32 next_index = slave_info->head;
235
236			hash_table[hash_index].tx_slave = assigned_slave;
237			hash_table[hash_index].next = next_index;
238			hash_table[hash_index].prev = TLB_NULL_INDEX;
239
240			if (next_index != TLB_NULL_INDEX)
241				hash_table[next_index].prev = hash_index;
242
243			slave_info->head = hash_index;
244			slave_info->load +=
245				hash_table[hash_index].load_history;
246		}
247	}
248
249	if (assigned_slave)
250		hash_table[hash_index].tx_bytes += skb_len;
251
252	return assigned_slave;
253}
254
255static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
256					u32 skb_len)
257{
258	struct slave *tx_slave;
259
260	/* We don't need to disable softirq here, becase
261	 * tlb_choose_channel() is only called by bond_alb_xmit()
262	 * which already has softirq disabled.
263	 */
264	spin_lock(&bond->mode_lock);
265	tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
266	spin_unlock(&bond->mode_lock);
267
268	return tx_slave;
269}
270
271/*********************** rlb specific functions ***************************/
272
273/* when an ARP REPLY is received from a client update its info
274 * in the rx_hashtbl
275 */
276static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
277{
278	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
279	struct rlb_client_info *client_info;
280	u32 hash_index;
281
282	spin_lock_bh(&bond->mode_lock);
283
284	hash_index = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
285	client_info = &(bond_info->rx_hashtbl[hash_index]);
286
287	if ((client_info->assigned) &&
288	    (client_info->ip_src == arp->ip_dst) &&
289	    (client_info->ip_dst == arp->ip_src) &&
290	    (!ether_addr_equal_64bits(client_info->mac_dst, arp->mac_src))) {
291		/* update the clients MAC address */
292		ether_addr_copy(client_info->mac_dst, arp->mac_src);
293		client_info->ntt = 1;
294		bond_info->rx_ntt = 1;
295	}
296
297	spin_unlock_bh(&bond->mode_lock);
298}
299
300static int rlb_arp_recv(const struct sk_buff *skb, struct bonding *bond,
301			struct slave *slave)
302{
303	struct arp_pkt *arp, _arp;
304
305	if (skb->protocol != cpu_to_be16(ETH_P_ARP))
306		goto out;
307
308	arp = skb_header_pointer(skb, 0, sizeof(_arp), &_arp);
309	if (!arp)
310		goto out;
311
312	/* We received an ARP from arp->ip_src.
313	 * We might have used this IP address previously (on the bonding host
314	 * itself or on a system that is bridged together with the bond).
315	 * However, if arp->mac_src is different than what is stored in
316	 * rx_hashtbl, some other host is now using the IP and we must prevent
317	 * sending out client updates with this IP address and the old MAC
318	 * address.
319	 * Clean up all hash table entries that have this address as ip_src but
320	 * have a different mac_src.
321	 */
322	rlb_purge_src_ip(bond, arp);
323
324	if (arp->op_code == htons(ARPOP_REPLY)) {
325		/* update rx hash table for this ARP */
326		rlb_update_entry_from_arp(bond, arp);
327		netdev_dbg(bond->dev, "Server received an ARP Reply from client\n");
328	}
329out:
330	return RX_HANDLER_ANOTHER;
331}
332
333/* Caller must hold rcu_read_lock() */
334static struct slave *__rlb_next_rx_slave(struct bonding *bond)
335{
336	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
337	struct slave *before = NULL, *rx_slave = NULL, *slave;
338	struct list_head *iter;
339	bool found = false;
340
341	bond_for_each_slave_rcu(bond, slave, iter) {
342		if (!bond_slave_can_tx(slave))
343			continue;
344		if (!found) {
345			if (!before || before->speed < slave->speed)
346				before = slave;
347		} else {
348			if (!rx_slave || rx_slave->speed < slave->speed)
349				rx_slave = slave;
350		}
351		if (slave == bond_info->rx_slave)
352			found = true;
353	}
354	/* we didn't find anything after the current or we have something
355	 * better before and up to the current slave
356	 */
357	if (!rx_slave || (before && rx_slave->speed < before->speed))
358		rx_slave = before;
359
360	if (rx_slave)
361		bond_info->rx_slave = rx_slave;
362
363	return rx_slave;
364}
365
366/* Caller must hold RTNL, rcu_read_lock is obtained only to silence checkers */
367static struct slave *rlb_next_rx_slave(struct bonding *bond)
368{
369	struct slave *rx_slave;
370
371	ASSERT_RTNL();
372
373	rcu_read_lock();
374	rx_slave = __rlb_next_rx_slave(bond);
375	rcu_read_unlock();
376
377	return rx_slave;
378}
379
380/* teach the switch the mac of a disabled slave
381 * on the primary for fault tolerance
382 *
383 * Caller must hold RTNL
384 */
385static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
386{
387	struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
388
389	if (!curr_active)
390		return;
391
392	if (!bond->alb_info.primary_is_promisc) {
393		if (!dev_set_promiscuity(curr_active->dev, 1))
394			bond->alb_info.primary_is_promisc = 1;
395		else
396			bond->alb_info.primary_is_promisc = 0;
397	}
398
399	bond->alb_info.rlb_promisc_timeout_counter = 0;
400
401	alb_send_learning_packets(curr_active, addr, true);
402}
403
404/* slave being removed should not be active at this point
405 *
406 * Caller must hold rtnl.
407 */
408static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
409{
410	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
411	struct rlb_client_info *rx_hash_table;
412	u32 index, next_index;
413
414	/* clear slave from rx_hashtbl */
415	spin_lock_bh(&bond->mode_lock);
416
417	rx_hash_table = bond_info->rx_hashtbl;
418	index = bond_info->rx_hashtbl_used_head;
419	for (; index != RLB_NULL_INDEX; index = next_index) {
420		next_index = rx_hash_table[index].used_next;
421		if (rx_hash_table[index].slave == slave) {
422			struct slave *assigned_slave = rlb_next_rx_slave(bond);
423
424			if (assigned_slave) {
425				rx_hash_table[index].slave = assigned_slave;
426				if (!ether_addr_equal_64bits(rx_hash_table[index].mac_dst,
427							     mac_bcast)) {
428					bond_info->rx_hashtbl[index].ntt = 1;
429					bond_info->rx_ntt = 1;
430					/* A slave has been removed from the
431					 * table because it is either disabled
432					 * or being released. We must retry the
433					 * update to avoid clients from not
434					 * being updated & disconnecting when
435					 * there is stress
436					 */
437					bond_info->rlb_update_retry_counter =
438						RLB_UPDATE_RETRY;
439				}
440			} else {  /* there is no active slave */
441				rx_hash_table[index].slave = NULL;
442			}
443		}
444	}
445
446	spin_unlock_bh(&bond->mode_lock);
447
448	if (slave != rtnl_dereference(bond->curr_active_slave))
449		rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
450}
451
452static void rlb_update_client(struct rlb_client_info *client_info)
453{
454	int i;
455
456	if (!client_info->slave)
457		return;
458
459	for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
460		struct sk_buff *skb;
461
462		skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
463				 client_info->ip_dst,
464				 client_info->slave->dev,
465				 client_info->ip_src,
466				 client_info->mac_dst,
467				 client_info->slave->dev->dev_addr,
468				 client_info->mac_dst);
469		if (!skb) {
470			netdev_err(client_info->slave->bond->dev,
471				   "failed to create an ARP packet\n");
472			continue;
473		}
474
475		skb->dev = client_info->slave->dev;
476
477		if (client_info->vlan_id) {
478			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
479					       client_info->vlan_id);
480		}
481
482		arp_xmit(skb);
483	}
484}
485
486/* sends ARP REPLIES that update the clients that need updating */
487static void rlb_update_rx_clients(struct bonding *bond)
488{
489	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
490	struct rlb_client_info *client_info;
491	u32 hash_index;
492
493	spin_lock_bh(&bond->mode_lock);
494
495	hash_index = bond_info->rx_hashtbl_used_head;
496	for (; hash_index != RLB_NULL_INDEX;
497	     hash_index = client_info->used_next) {
498		client_info = &(bond_info->rx_hashtbl[hash_index]);
499		if (client_info->ntt) {
500			rlb_update_client(client_info);
501			if (bond_info->rlb_update_retry_counter == 0)
502				client_info->ntt = 0;
503		}
504	}
505
506	/* do not update the entries again until this counter is zero so that
507	 * not to confuse the clients.
508	 */
509	bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
510
511	spin_unlock_bh(&bond->mode_lock);
512}
513
514/* The slave was assigned a new mac address - update the clients */
515static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
516{
517	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
518	struct rlb_client_info *client_info;
519	int ntt = 0;
520	u32 hash_index;
521
522	spin_lock_bh(&bond->mode_lock);
523
524	hash_index = bond_info->rx_hashtbl_used_head;
525	for (; hash_index != RLB_NULL_INDEX;
526	     hash_index = client_info->used_next) {
527		client_info = &(bond_info->rx_hashtbl[hash_index]);
528
529		if ((client_info->slave == slave) &&
530		    !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
531			client_info->ntt = 1;
532			ntt = 1;
533		}
534	}
535
536	/* update the team's flag only after the whole iteration */
537	if (ntt) {
538		bond_info->rx_ntt = 1;
539		/* fasten the change */
540		bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
541	}
542
543	spin_unlock_bh(&bond->mode_lock);
544}
545
546/* mark all clients using src_ip to be updated */
547static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
548{
549	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
550	struct rlb_client_info *client_info;
551	u32 hash_index;
552
553	spin_lock(&bond->mode_lock);
554
555	hash_index = bond_info->rx_hashtbl_used_head;
556	for (; hash_index != RLB_NULL_INDEX;
557	     hash_index = client_info->used_next) {
558		client_info = &(bond_info->rx_hashtbl[hash_index]);
559
560		if (!client_info->slave) {
561			netdev_err(bond->dev, "found a client with no channel in the client's hash table\n");
562			continue;
563		}
564		/* update all clients using this src_ip, that are not assigned
565		 * to the team's address (curr_active_slave) and have a known
566		 * unicast mac address.
567		 */
568		if ((client_info->ip_src == src_ip) &&
569		    !ether_addr_equal_64bits(client_info->slave->dev->dev_addr,
570					     bond->dev->dev_addr) &&
571		    !ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
572			client_info->ntt = 1;
573			bond_info->rx_ntt = 1;
574		}
575	}
576
577	spin_unlock(&bond->mode_lock);
578}
579
580static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
581{
582	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
583	struct arp_pkt *arp = arp_pkt(skb);
584	struct slave *assigned_slave, *curr_active_slave;
585	struct rlb_client_info *client_info;
586	u32 hash_index = 0;
587
588	spin_lock(&bond->mode_lock);
589
590	curr_active_slave = rcu_dereference(bond->curr_active_slave);
591
592	hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
593	client_info = &(bond_info->rx_hashtbl[hash_index]);
594
595	if (client_info->assigned) {
596		if ((client_info->ip_src == arp->ip_src) &&
597		    (client_info->ip_dst == arp->ip_dst)) {
598			/* the entry is already assigned to this client */
599			if (!ether_addr_equal_64bits(arp->mac_dst, mac_bcast)) {
600				/* update mac address from arp */
601				ether_addr_copy(client_info->mac_dst, arp->mac_dst);
602			}
603			ether_addr_copy(client_info->mac_src, arp->mac_src);
604
605			assigned_slave = client_info->slave;
606			if (assigned_slave) {
607				spin_unlock(&bond->mode_lock);
608				return assigned_slave;
609			}
610		} else {
611			/* the entry is already assigned to some other client,
612			 * move the old client to primary (curr_active_slave) so
613			 * that the new client can be assigned to this entry.
614			 */
615			if (curr_active_slave &&
616			    client_info->slave != curr_active_slave) {
617				client_info->slave = curr_active_slave;
618				rlb_update_client(client_info);
619			}
620		}
621	}
622	/* assign a new slave */
623	assigned_slave = __rlb_next_rx_slave(bond);
624
625	if (assigned_slave) {
626		if (!(client_info->assigned &&
627		      client_info->ip_src == arp->ip_src)) {
628			/* ip_src is going to be updated,
629			 * fix the src hash list
630			 */
631			u32 hash_src = _simple_hash((u8 *)&arp->ip_src,
632						    sizeof(arp->ip_src));
633			rlb_src_unlink(bond, hash_index);
634			rlb_src_link(bond, hash_src, hash_index);
635		}
636
637		client_info->ip_src = arp->ip_src;
638		client_info->ip_dst = arp->ip_dst;
639		/* arp->mac_dst is broadcast for arp reqeusts.
640		 * will be updated with clients actual unicast mac address
641		 * upon receiving an arp reply.
642		 */
643		ether_addr_copy(client_info->mac_dst, arp->mac_dst);
644		ether_addr_copy(client_info->mac_src, arp->mac_src);
645		client_info->slave = assigned_slave;
646
647		if (!ether_addr_equal_64bits(client_info->mac_dst, mac_bcast)) {
648			client_info->ntt = 1;
649			bond->alb_info.rx_ntt = 1;
650		} else {
651			client_info->ntt = 0;
652		}
653
654		if (vlan_get_tag(skb, &client_info->vlan_id))
655			client_info->vlan_id = 0;
656
657		if (!client_info->assigned) {
658			u32 prev_tbl_head = bond_info->rx_hashtbl_used_head;
659			bond_info->rx_hashtbl_used_head = hash_index;
660			client_info->used_next = prev_tbl_head;
661			if (prev_tbl_head != RLB_NULL_INDEX) {
662				bond_info->rx_hashtbl[prev_tbl_head].used_prev =
663					hash_index;
664			}
665			client_info->assigned = 1;
666		}
667	}
668
669	spin_unlock(&bond->mode_lock);
670
671	return assigned_slave;
672}
673
674/* chooses (and returns) transmit channel for arp reply
675 * does not choose channel for other arp types since they are
676 * sent on the curr_active_slave
677 */
678static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
679{
680	struct arp_pkt *arp = arp_pkt(skb);
681	struct slave *tx_slave = NULL;
682
683	/* Don't modify or load balance ARPs that do not originate locally
684	 * (e.g.,arrive via a bridge).
685	 */
686	if (!bond_slave_has_mac_rx(bond, arp->mac_src))
687		return NULL;
688
689	if (arp->op_code == htons(ARPOP_REPLY)) {
690		/* the arp must be sent on the selected rx channel */
691		tx_slave = rlb_choose_channel(skb, bond);
692		if (tx_slave)
693			ether_addr_copy(arp->mac_src, tx_slave->dev->dev_addr);
694		netdev_dbg(bond->dev, "Server sent ARP Reply packet\n");
695	} else if (arp->op_code == htons(ARPOP_REQUEST)) {
696		/* Create an entry in the rx_hashtbl for this client as a
697		 * place holder.
698		 * When the arp reply is received the entry will be updated
699		 * with the correct unicast address of the client.
700		 */
701		rlb_choose_channel(skb, bond);
702
703		/* The ARP reply packets must be delayed so that
704		 * they can cancel out the influence of the ARP request.
705		 */
706		bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
707
708		/* arp requests are broadcast and are sent on the primary
709		 * the arp request will collapse all clients on the subnet to
710		 * the primary slave. We must register these clients to be
711		 * updated with their assigned mac.
712		 */
713		rlb_req_update_subnet_clients(bond, arp->ip_src);
714		netdev_dbg(bond->dev, "Server sent ARP Request packet\n");
715	}
716
717	return tx_slave;
718}
719
720static void rlb_rebalance(struct bonding *bond)
721{
722	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
723	struct slave *assigned_slave;
724	struct rlb_client_info *client_info;
725	int ntt;
726	u32 hash_index;
727
728	spin_lock_bh(&bond->mode_lock);
729
730	ntt = 0;
731	hash_index = bond_info->rx_hashtbl_used_head;
732	for (; hash_index != RLB_NULL_INDEX;
733	     hash_index = client_info->used_next) {
734		client_info = &(bond_info->rx_hashtbl[hash_index]);
735		assigned_slave = __rlb_next_rx_slave(bond);
736		if (assigned_slave && (client_info->slave != assigned_slave)) {
737			client_info->slave = assigned_slave;
738			client_info->ntt = 1;
739			ntt = 1;
740		}
741	}
742
743	/* update the team's flag only after the whole iteration */
744	if (ntt)
745		bond_info->rx_ntt = 1;
746	spin_unlock_bh(&bond->mode_lock);
747}
748
749/* Caller must hold mode_lock */
750static void rlb_init_table_entry_dst(struct rlb_client_info *entry)
751{
752	entry->used_next = RLB_NULL_INDEX;
753	entry->used_prev = RLB_NULL_INDEX;
754	entry->assigned = 0;
755	entry->slave = NULL;
756	entry->vlan_id = 0;
757}
758static void rlb_init_table_entry_src(struct rlb_client_info *entry)
759{
760	entry->src_first = RLB_NULL_INDEX;
761	entry->src_prev = RLB_NULL_INDEX;
762	entry->src_next = RLB_NULL_INDEX;
763}
764
765static void rlb_init_table_entry(struct rlb_client_info *entry)
766{
767	memset(entry, 0, sizeof(struct rlb_client_info));
768	rlb_init_table_entry_dst(entry);
769	rlb_init_table_entry_src(entry);
770}
771
772static void rlb_delete_table_entry_dst(struct bonding *bond, u32 index)
773{
774	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
775	u32 next_index = bond_info->rx_hashtbl[index].used_next;
776	u32 prev_index = bond_info->rx_hashtbl[index].used_prev;
777
778	if (index == bond_info->rx_hashtbl_used_head)
779		bond_info->rx_hashtbl_used_head = next_index;
780	if (prev_index != RLB_NULL_INDEX)
781		bond_info->rx_hashtbl[prev_index].used_next = next_index;
782	if (next_index != RLB_NULL_INDEX)
783		bond_info->rx_hashtbl[next_index].used_prev = prev_index;
784}
785
786/* unlink a rlb hash table entry from the src list */
787static void rlb_src_unlink(struct bonding *bond, u32 index)
788{
789	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
790	u32 next_index = bond_info->rx_hashtbl[index].src_next;
791	u32 prev_index = bond_info->rx_hashtbl[index].src_prev;
792
793	bond_info->rx_hashtbl[index].src_next = RLB_NULL_INDEX;
794	bond_info->rx_hashtbl[index].src_prev = RLB_NULL_INDEX;
795
796	if (next_index != RLB_NULL_INDEX)
797		bond_info->rx_hashtbl[next_index].src_prev = prev_index;
798
799	if (prev_index == RLB_NULL_INDEX)
800		return;
801
802	/* is prev_index pointing to the head of this list? */
803	if (bond_info->rx_hashtbl[prev_index].src_first == index)
804		bond_info->rx_hashtbl[prev_index].src_first = next_index;
805	else
806		bond_info->rx_hashtbl[prev_index].src_next = next_index;
807
808}
809
810static void rlb_delete_table_entry(struct bonding *bond, u32 index)
811{
812	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
813	struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
814
815	rlb_delete_table_entry_dst(bond, index);
816	rlb_init_table_entry_dst(entry);
817
818	rlb_src_unlink(bond, index);
819}
820
821/* add the rx_hashtbl[ip_dst_hash] entry to the list
822 * of entries with identical ip_src_hash
823 */
824static void rlb_src_link(struct bonding *bond, u32 ip_src_hash, u32 ip_dst_hash)
825{
826	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
827	u32 next;
828
829	bond_info->rx_hashtbl[ip_dst_hash].src_prev = ip_src_hash;
830	next = bond_info->rx_hashtbl[ip_src_hash].src_first;
831	bond_info->rx_hashtbl[ip_dst_hash].src_next = next;
832	if (next != RLB_NULL_INDEX)
833		bond_info->rx_hashtbl[next].src_prev = ip_dst_hash;
834	bond_info->rx_hashtbl[ip_src_hash].src_first = ip_dst_hash;
835}
836
837/* deletes all rx_hashtbl entries with arp->ip_src if their mac_src does
838 * not match arp->mac_src
839 */
840static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp)
841{
842	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
843	u32 ip_src_hash = _simple_hash((u8 *)&(arp->ip_src), sizeof(arp->ip_src));
844	u32 index;
845
846	spin_lock_bh(&bond->mode_lock);
847
848	index = bond_info->rx_hashtbl[ip_src_hash].src_first;
849	while (index != RLB_NULL_INDEX) {
850		struct rlb_client_info *entry = &(bond_info->rx_hashtbl[index]);
851		u32 next_index = entry->src_next;
852		if (entry->ip_src == arp->ip_src &&
853		    !ether_addr_equal_64bits(arp->mac_src, entry->mac_src))
854				rlb_delete_table_entry(bond, index);
855		index = next_index;
856	}
857	spin_unlock_bh(&bond->mode_lock);
858}
859
860static int rlb_initialize(struct bonding *bond)
861{
862	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
863	struct rlb_client_info	*new_hashtbl;
864	int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
865	int i;
866
867	new_hashtbl = kmalloc(size, GFP_KERNEL);
868	if (!new_hashtbl)
869		return -1;
870
871	spin_lock_bh(&bond->mode_lock);
872
873	bond_info->rx_hashtbl = new_hashtbl;
874
875	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
876
877	for (i = 0; i < RLB_HASH_TABLE_SIZE; i++)
878		rlb_init_table_entry(bond_info->rx_hashtbl + i);
879
880	spin_unlock_bh(&bond->mode_lock);
881
882	/* register to receive ARPs */
883	bond->recv_probe = rlb_arp_recv;
884
885	return 0;
886}
887
888static void rlb_deinitialize(struct bonding *bond)
889{
890	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
891
892	spin_lock_bh(&bond->mode_lock);
893
894	kfree(bond_info->rx_hashtbl);
895	bond_info->rx_hashtbl = NULL;
896	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
897
898	spin_unlock_bh(&bond->mode_lock);
899}
900
901static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
902{
903	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
904	u32 curr_index;
905
906	spin_lock_bh(&bond->mode_lock);
907
908	curr_index = bond_info->rx_hashtbl_used_head;
909	while (curr_index != RLB_NULL_INDEX) {
910		struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
911		u32 next_index = bond_info->rx_hashtbl[curr_index].used_next;
912
913		if (curr->vlan_id == vlan_id)
914			rlb_delete_table_entry(bond, curr_index);
915
916		curr_index = next_index;
917	}
918
919	spin_unlock_bh(&bond->mode_lock);
920}
921
922/*********************** tlb/rlb shared functions *********************/
923
924static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
925			    __be16 vlan_proto, u16 vid)
926{
927	struct learning_pkt pkt;
928	struct sk_buff *skb;
929	int size = sizeof(struct learning_pkt);
930	char *data;
931
932	memset(&pkt, 0, size);
933	ether_addr_copy(pkt.mac_dst, mac_addr);
934	ether_addr_copy(pkt.mac_src, mac_addr);
935	pkt.type = cpu_to_be16(ETH_P_LOOPBACK);
936
937	skb = dev_alloc_skb(size);
938	if (!skb)
939		return;
940
941	data = skb_put(skb, size);
942	memcpy(data, &pkt, size);
943
944	skb_reset_mac_header(skb);
945	skb->network_header = skb->mac_header + ETH_HLEN;
946	skb->protocol = pkt.type;
947	skb->priority = TC_PRIO_CONTROL;
948	skb->dev = slave->dev;
949
950	if (vid)
951		__vlan_hwaccel_put_tag(skb, vlan_proto, vid);
952
953	dev_queue_xmit(skb);
954}
955
956static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
957				      bool strict_match)
958{
959	struct bonding *bond = bond_get_bond_by_slave(slave);
960	struct net_device *upper;
961	struct list_head *iter;
962	struct bond_vlan_tag *tags;
963
964	/* send untagged */
965	alb_send_lp_vid(slave, mac_addr, 0, 0);
966
967	/* loop through all devices and see if we need to send a packet
968	 * for that device.
969	 */
970	rcu_read_lock();
971	netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
972		if (is_vlan_dev(upper) && vlan_get_encap_level(upper) == 0) {
973			if (strict_match &&
974			    ether_addr_equal_64bits(mac_addr,
975						    upper->dev_addr)) {
976				alb_send_lp_vid(slave, mac_addr,
977						vlan_dev_vlan_proto(upper),
978						vlan_dev_vlan_id(upper));
979			} else if (!strict_match) {
980				alb_send_lp_vid(slave, upper->dev_addr,
981						vlan_dev_vlan_proto(upper),
982						vlan_dev_vlan_id(upper));
983			}
984		}
985
986		/* If this is a macvlan device, then only send updates
987		 * when strict_match is turned off.
988		 */
989		if (netif_is_macvlan(upper) && !strict_match) {
990			tags = bond_verify_device_path(bond->dev, upper, 0);
991			if (IS_ERR_OR_NULL(tags))
992				BUG();
993			alb_send_lp_vid(slave, upper->dev_addr,
994					tags[0].vlan_proto, tags[0].vlan_id);
995			kfree(tags);
996		}
997	}
998	rcu_read_unlock();
999}
1000
1001static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
1002{
1003	struct net_device *dev = slave->dev;
1004	struct sockaddr s_addr;
1005
1006	if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
1007		memcpy(dev->dev_addr, addr, dev->addr_len);
1008		return 0;
1009	}
1010
1011	/* for rlb each slave must have a unique hw mac addresses so that
1012	 * each slave will receive packets destined to a different mac
1013	 */
1014	memcpy(s_addr.sa_data, addr, dev->addr_len);
1015	s_addr.sa_family = dev->type;
1016	if (dev_set_mac_address(dev, &s_addr)) {
1017		netdev_err(slave->bond->dev, "dev_set_mac_address of dev %s failed! ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
1018			   dev->name);
1019		return -EOPNOTSUPP;
1020	}
1021	return 0;
1022}
1023
1024/* Swap MAC addresses between two slaves.
1025 *
1026 * Called with RTNL held, and no other locks.
1027 */
1028static void alb_swap_mac_addr(struct slave *slave1, struct slave *slave2)
1029{
1030	u8 tmp_mac_addr[ETH_ALEN];
1031
1032	ether_addr_copy(tmp_mac_addr, slave1->dev->dev_addr);
1033	alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
1034	alb_set_slave_mac_addr(slave2, tmp_mac_addr);
1035
1036}
1037
1038/* Send learning packets after MAC address swap.
1039 *
1040 * Called with RTNL and no other locks
1041 */
1042static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
1043				struct slave *slave2)
1044{
1045	int slaves_state_differ = (bond_slave_can_tx(slave1) != bond_slave_can_tx(slave2));
1046	struct slave *disabled_slave = NULL;
1047
1048	ASSERT_RTNL();
1049
1050	/* fasten the change in the switch */
1051	if (bond_slave_can_tx(slave1)) {
1052		alb_send_learning_packets(slave1, slave1->dev->dev_addr, false);
1053		if (bond->alb_info.rlb_enabled) {
1054			/* inform the clients that the mac address
1055			 * has changed
1056			 */
1057			rlb_req_update_slave_clients(bond, slave1);
1058		}
1059	} else {
1060		disabled_slave = slave1;
1061	}
1062
1063	if (bond_slave_can_tx(slave2)) {
1064		alb_send_learning_packets(slave2, slave2->dev->dev_addr, false);
1065		if (bond->alb_info.rlb_enabled) {
1066			/* inform the clients that the mac address
1067			 * has changed
1068			 */
1069			rlb_req_update_slave_clients(bond, slave2);
1070		}
1071	} else {
1072		disabled_slave = slave2;
1073	}
1074
1075	if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1076		/* A disabled slave was assigned an active mac addr */
1077		rlb_teach_disabled_mac_on_primary(bond,
1078						  disabled_slave->dev->dev_addr);
1079	}
1080}
1081
1082/**
1083 * alb_change_hw_addr_on_detach
1084 * @bond: bonding we're working on
1085 * @slave: the slave that was just detached
1086 *
1087 * We assume that @slave was already detached from the slave list.
1088 *
1089 * If @slave's permanent hw address is different both from its current
1090 * address and from @bond's address, then somewhere in the bond there's
1091 * a slave that has @slave's permanet address as its current address.
1092 * We'll make sure that that slave no longer uses @slave's permanent address.
1093 *
1094 * Caller must hold RTNL and no other locks
1095 */
1096static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1097{
1098	int perm_curr_diff;
1099	int perm_bond_diff;
1100	struct slave *found_slave;
1101
1102	perm_curr_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1103						  slave->dev->dev_addr);
1104	perm_bond_diff = !ether_addr_equal_64bits(slave->perm_hwaddr,
1105						  bond->dev->dev_addr);
1106
1107	if (perm_curr_diff && perm_bond_diff) {
1108		found_slave = bond_slave_has_mac(bond, slave->perm_hwaddr);
1109
1110		if (found_slave) {
1111			alb_swap_mac_addr(slave, found_slave);
1112			alb_fasten_mac_swap(bond, slave, found_slave);
1113		}
1114	}
1115}
1116
1117/**
1118 * alb_handle_addr_collision_on_attach
1119 * @bond: bonding we're working on
1120 * @slave: the slave that was just attached
1121 *
1122 * checks uniqueness of slave's mac address and handles the case the
1123 * new slave uses the bonds mac address.
1124 *
1125 * If the permanent hw address of @slave is @bond's hw address, we need to
1126 * find a different hw address to give @slave, that isn't in use by any other
1127 * slave in the bond. This address must be, of course, one of the permanent
1128 * addresses of the other slaves.
1129 *
1130 * We go over the slave list, and for each slave there we compare its
1131 * permanent hw address with the current address of all the other slaves.
1132 * If no match was found, then we've found a slave with a permanent address
1133 * that isn't used by any other slave in the bond, so we can assign it to
1134 * @slave.
1135 *
1136 * assumption: this function is called before @slave is attached to the
1137 *	       bond slave list.
1138 */
1139static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1140{
1141	struct slave *has_bond_addr = rcu_access_pointer(bond->curr_active_slave);
1142	struct slave *tmp_slave1, *free_mac_slave = NULL;
1143	struct list_head *iter;
1144
1145	if (!bond_has_slaves(bond)) {
1146		/* this is the first slave */
1147		return 0;
1148	}
1149
1150	/* if slave's mac address differs from bond's mac address
1151	 * check uniqueness of slave's mac address against the other
1152	 * slaves in the bond.
1153	 */
1154	if (!ether_addr_equal_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1155		if (!bond_slave_has_mac(bond, slave->dev->dev_addr))
1156			return 0;
1157
1158		/* Try setting slave mac to bond address and fall-through
1159		 * to code handling that situation below...
1160		 */
1161		alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1162	}
1163
1164	/* The slave's address is equal to the address of the bond.
1165	 * Search for a spare address in the bond for this slave.
1166	 */
1167	bond_for_each_slave(bond, tmp_slave1, iter) {
1168		if (!bond_slave_has_mac(bond, tmp_slave1->perm_hwaddr)) {
1169			/* no slave has tmp_slave1's perm addr
1170			 * as its curr addr
1171			 */
1172			free_mac_slave = tmp_slave1;
1173			break;
1174		}
1175
1176		if (!has_bond_addr) {
1177			if (ether_addr_equal_64bits(tmp_slave1->dev->dev_addr,
1178						    bond->dev->dev_addr)) {
1179
1180				has_bond_addr = tmp_slave1;
1181			}
1182		}
1183	}
1184
1185	if (free_mac_slave) {
1186		alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1187
1188		netdev_warn(bond->dev, "the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1189			    slave->dev->name, free_mac_slave->dev->name);
1190
1191	} else if (has_bond_addr) {
1192		netdev_err(bond->dev, "the hw address of slave %s is in use by the bond; couldn't find a slave with a free hw address to give it (this should not have happened)\n",
1193			   slave->dev->name);
1194		return -EFAULT;
1195	}
1196
1197	return 0;
1198}
1199
1200/**
1201 * alb_set_mac_address
1202 * @bond:
1203 * @addr:
1204 *
1205 * In TLB mode all slaves are configured to the bond's hw address, but set
1206 * their dev_addr field to different addresses (based on their permanent hw
1207 * addresses).
1208 *
1209 * For each slave, this function sets the interface to the new address and then
1210 * changes its dev_addr field to its previous value.
1211 *
1212 * Unwinding assumes bond's mac address has not yet changed.
1213 */
1214static int alb_set_mac_address(struct bonding *bond, void *addr)
1215{
1216	struct slave *slave, *rollback_slave;
1217	struct list_head *iter;
1218	struct sockaddr sa;
1219	char tmp_addr[ETH_ALEN];
1220	int res;
1221
1222	if (bond->alb_info.rlb_enabled)
1223		return 0;
1224
1225	bond_for_each_slave(bond, slave, iter) {
1226		/* save net_device's current hw address */
1227		ether_addr_copy(tmp_addr, slave->dev->dev_addr);
1228
1229		res = dev_set_mac_address(slave->dev, addr);
1230
1231		/* restore net_device's hw address */
1232		ether_addr_copy(slave->dev->dev_addr, tmp_addr);
1233
1234		if (res)
1235			goto unwind;
1236	}
1237
1238	return 0;
1239
1240unwind:
1241	memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1242	sa.sa_family = bond->dev->type;
1243
1244	/* unwind from head to the slave that failed */
1245	bond_for_each_slave(bond, rollback_slave, iter) {
1246		if (rollback_slave == slave)
1247			break;
1248		ether_addr_copy(tmp_addr, rollback_slave->dev->dev_addr);
1249		dev_set_mac_address(rollback_slave->dev, &sa);
1250		ether_addr_copy(rollback_slave->dev->dev_addr, tmp_addr);
1251	}
1252
1253	return res;
1254}
1255
1256/************************ exported alb funcions ************************/
1257
1258int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1259{
1260	int res;
1261
1262	res = tlb_initialize(bond);
1263	if (res)
1264		return res;
1265
1266	if (rlb_enabled) {
1267		bond->alb_info.rlb_enabled = 1;
1268		res = rlb_initialize(bond);
1269		if (res) {
1270			tlb_deinitialize(bond);
1271			return res;
1272		}
1273	} else {
1274		bond->alb_info.rlb_enabled = 0;
1275	}
1276
1277	return 0;
1278}
1279
1280void bond_alb_deinitialize(struct bonding *bond)
1281{
1282	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1283
1284	tlb_deinitialize(bond);
1285
1286	if (bond_info->rlb_enabled)
1287		rlb_deinitialize(bond);
1288}
1289
1290static int bond_do_alb_xmit(struct sk_buff *skb, struct bonding *bond,
1291			    struct slave *tx_slave)
1292{
1293	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1294	struct ethhdr *eth_data = eth_hdr(skb);
1295
1296	if (!tx_slave) {
1297		/* unbalanced or unassigned, send through primary */
1298		tx_slave = rcu_dereference(bond->curr_active_slave);
1299		if (bond->params.tlb_dynamic_lb)
1300			bond_info->unbalanced_load += skb->len;
1301	}
1302
1303	if (tx_slave && bond_slave_can_tx(tx_slave)) {
1304		if (tx_slave != rcu_access_pointer(bond->curr_active_slave)) {
1305			ether_addr_copy(eth_data->h_source,
1306					tx_slave->dev->dev_addr);
1307		}
1308
1309		bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1310		goto out;
1311	}
1312
1313	if (tx_slave && bond->params.tlb_dynamic_lb) {
1314		spin_lock(&bond->mode_lock);
1315		__tlb_clear_slave(bond, tx_slave, 0);
1316		spin_unlock(&bond->mode_lock);
1317	}
1318
1319	/* no suitable interface, frame not sent */
1320	bond_tx_drop(bond->dev, skb);
1321out:
1322	return NETDEV_TX_OK;
1323}
1324
1325int bond_tlb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1326{
1327	struct bonding *bond = netdev_priv(bond_dev);
1328	struct ethhdr *eth_data;
1329	struct slave *tx_slave = NULL;
1330	u32 hash_index;
1331
1332	skb_reset_mac_header(skb);
1333	eth_data = eth_hdr(skb);
1334
1335	/* Do not TX balance any multicast or broadcast */
1336	if (!is_multicast_ether_addr(eth_data->h_dest)) {
1337		switch (skb->protocol) {
1338		case htons(ETH_P_IP):
1339		case htons(ETH_P_IPX):
1340		    /* In case of IPX, it will falback to L2 hash */
1341		case htons(ETH_P_IPV6):
1342			hash_index = bond_xmit_hash(bond, skb);
1343			if (bond->params.tlb_dynamic_lb) {
1344				tx_slave = tlb_choose_channel(bond,
1345							      hash_index & 0xFF,
1346							      skb->len);
1347			} else {
1348				struct bond_up_slave *slaves;
1349				unsigned int count;
1350
1351				slaves = rcu_dereference(bond->slave_arr);
1352				count = slaves ? ACCESS_ONCE(slaves->count) : 0;
1353				if (likely(count))
1354					tx_slave = slaves->arr[hash_index %
1355							       count];
1356			}
1357			break;
1358		}
1359	}
1360	return bond_do_alb_xmit(skb, bond, tx_slave);
1361}
1362
1363int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1364{
1365	struct bonding *bond = netdev_priv(bond_dev);
1366	struct ethhdr *eth_data;
1367	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1368	struct slave *tx_slave = NULL;
1369	static const __be32 ip_bcast = htonl(0xffffffff);
1370	int hash_size = 0;
1371	bool do_tx_balance = true;
1372	u32 hash_index = 0;
1373	const u8 *hash_start = NULL;
1374	struct ipv6hdr *ip6hdr;
1375
1376	skb_reset_mac_header(skb);
1377	eth_data = eth_hdr(skb);
1378
1379	switch (ntohs(skb->protocol)) {
1380	case ETH_P_IP: {
1381		const struct iphdr *iph = ip_hdr(skb);
1382
1383		if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast) ||
1384		    (iph->daddr == ip_bcast) ||
1385		    (iph->protocol == IPPROTO_IGMP)) {
1386			do_tx_balance = false;
1387			break;
1388		}
1389		hash_start = (char *)&(iph->daddr);
1390		hash_size = sizeof(iph->daddr);
1391	}
1392		break;
1393	case ETH_P_IPV6:
1394		/* IPv6 doesn't really use broadcast mac address, but leave
1395		 * that here just in case.
1396		 */
1397		if (ether_addr_equal_64bits(eth_data->h_dest, mac_bcast)) {
1398			do_tx_balance = false;
1399			break;
1400		}
1401
1402		/* IPv6 uses all-nodes multicast as an equivalent to
1403		 * broadcasts in IPv4.
1404		 */
1405		if (ether_addr_equal_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1406			do_tx_balance = false;
1407			break;
1408		}
1409
1410		/* Additianally, DAD probes should not be tx-balanced as that
1411		 * will lead to false positives for duplicate addresses and
1412		 * prevent address configuration from working.
1413		 */
1414		ip6hdr = ipv6_hdr(skb);
1415		if (ipv6_addr_any(&ip6hdr->saddr)) {
1416			do_tx_balance = false;
1417			break;
1418		}
1419
1420		hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1421		hash_size = sizeof(ipv6_hdr(skb)->daddr);
1422		break;
1423	case ETH_P_IPX:
1424		if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1425			/* something is wrong with this packet */
1426			do_tx_balance = false;
1427			break;
1428		}
1429
1430		if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1431			/* The only protocol worth balancing in
1432			 * this family since it has an "ARP" like
1433			 * mechanism
1434			 */
1435			do_tx_balance = false;
1436			break;
1437		}
1438
1439		hash_start = (char *)eth_data->h_dest;
1440		hash_size = ETH_ALEN;
1441		break;
1442	case ETH_P_ARP:
1443		do_tx_balance = false;
1444		if (bond_info->rlb_enabled)
1445			tx_slave = rlb_arp_xmit(skb, bond);
1446		break;
1447	default:
1448		do_tx_balance = false;
1449		break;
1450	}
1451
1452	if (do_tx_balance) {
1453		hash_index = _simple_hash(hash_start, hash_size);
1454		tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1455	}
1456
1457	return bond_do_alb_xmit(skb, bond, tx_slave);
1458}
1459
1460void bond_alb_monitor(struct work_struct *work)
1461{
1462	struct bonding *bond = container_of(work, struct bonding,
1463					    alb_work.work);
1464	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1465	struct list_head *iter;
1466	struct slave *slave;
1467
1468	if (!bond_has_slaves(bond)) {
1469		bond_info->tx_rebalance_counter = 0;
1470		bond_info->lp_counter = 0;
1471		goto re_arm;
1472	}
1473
1474	rcu_read_lock();
1475
1476	bond_info->tx_rebalance_counter++;
1477	bond_info->lp_counter++;
1478
1479	/* send learning packets */
1480	if (bond_info->lp_counter >= BOND_ALB_LP_TICKS(bond)) {
1481		bool strict_match;
1482
1483		bond_for_each_slave_rcu(bond, slave, iter) {
1484			/* If updating current_active, use all currently
1485			 * user mac addreses (!strict_match).  Otherwise, only
1486			 * use mac of the slave device.
1487			 * In RLB mode, we always use strict matches.
1488			 */
1489			strict_match = (slave != rcu_access_pointer(bond->curr_active_slave) ||
1490					bond_info->rlb_enabled);
1491			alb_send_learning_packets(slave, slave->dev->dev_addr,
1492						  strict_match);
1493		}
1494		bond_info->lp_counter = 0;
1495	}
1496
1497	/* rebalance tx traffic */
1498	if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1499		bond_for_each_slave_rcu(bond, slave, iter) {
1500			tlb_clear_slave(bond, slave, 1);
1501			if (slave == rcu_access_pointer(bond->curr_active_slave)) {
1502				SLAVE_TLB_INFO(slave).load =
1503					bond_info->unbalanced_load /
1504						BOND_TLB_REBALANCE_INTERVAL;
1505				bond_info->unbalanced_load = 0;
1506			}
1507		}
1508		bond_info->tx_rebalance_counter = 0;
1509	}
1510
1511	if (bond_info->rlb_enabled) {
1512		if (bond_info->primary_is_promisc &&
1513		    (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1514
1515			/* dev_set_promiscuity requires rtnl and
1516			 * nothing else.  Avoid race with bond_close.
1517			 */
1518			rcu_read_unlock();
1519			if (!rtnl_trylock())
1520				goto re_arm;
1521
1522			bond_info->rlb_promisc_timeout_counter = 0;
1523
1524			/* If the primary was set to promiscuous mode
1525			 * because a slave was disabled then
1526			 * it can now leave promiscuous mode.
1527			 */
1528			dev_set_promiscuity(rtnl_dereference(bond->curr_active_slave)->dev,
1529					    -1);
1530			bond_info->primary_is_promisc = 0;
1531
1532			rtnl_unlock();
1533			rcu_read_lock();
1534		}
1535
1536		if (bond_info->rlb_rebalance) {
1537			bond_info->rlb_rebalance = 0;
1538			rlb_rebalance(bond);
1539		}
1540
1541		/* check if clients need updating */
1542		if (bond_info->rx_ntt) {
1543			if (bond_info->rlb_update_delay_counter) {
1544				--bond_info->rlb_update_delay_counter;
1545			} else {
1546				rlb_update_rx_clients(bond);
1547				if (bond_info->rlb_update_retry_counter)
1548					--bond_info->rlb_update_retry_counter;
1549				else
1550					bond_info->rx_ntt = 0;
1551			}
1552		}
1553	}
1554	rcu_read_unlock();
1555re_arm:
1556	queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1557}
1558
1559/* assumption: called before the slave is attached to the bond
1560 * and not locked by the bond lock
1561 */
1562int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1563{
1564	int res;
1565
1566	res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1567	if (res)
1568		return res;
1569
1570	res = alb_handle_addr_collision_on_attach(bond, slave);
1571	if (res)
1572		return res;
1573
1574	tlb_init_slave(slave);
1575
1576	/* order a rebalance ASAP */
1577	bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1578
1579	if (bond->alb_info.rlb_enabled)
1580		bond->alb_info.rlb_rebalance = 1;
1581
1582	return 0;
1583}
1584
1585/* Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1586 * if necessary.
1587 *
1588 * Caller must hold RTNL and no other locks
1589 */
1590void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1591{
1592	if (bond_has_slaves(bond))
1593		alb_change_hw_addr_on_detach(bond, slave);
1594
1595	tlb_clear_slave(bond, slave, 0);
1596
1597	if (bond->alb_info.rlb_enabled) {
1598		bond->alb_info.rx_slave = NULL;
1599		rlb_clear_slave(bond, slave);
1600	}
1601
1602}
1603
1604void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1605{
1606	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1607
1608	if (link == BOND_LINK_DOWN) {
1609		tlb_clear_slave(bond, slave, 0);
1610		if (bond->alb_info.rlb_enabled)
1611			rlb_clear_slave(bond, slave);
1612	} else if (link == BOND_LINK_UP) {
1613		/* order a rebalance ASAP */
1614		bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1615		if (bond->alb_info.rlb_enabled) {
1616			bond->alb_info.rlb_rebalance = 1;
1617			/* If the updelay module parameter is smaller than the
1618			 * forwarding delay of the switch the rebalance will
1619			 * not work because the rebalance arp replies will
1620			 * not be forwarded to the clients..
1621			 */
1622		}
1623	}
1624
1625	if (bond_is_nondyn_tlb(bond)) {
1626		if (bond_update_slave_arr(bond, NULL))
1627			pr_err("Failed to build slave-array for TLB mode.\n");
1628	}
1629}
1630
1631/**
1632 * bond_alb_handle_active_change - assign new curr_active_slave
1633 * @bond: our bonding struct
1634 * @new_slave: new slave to assign
1635 *
1636 * Set the bond->curr_active_slave to @new_slave and handle
1637 * mac address swapping and promiscuity changes as needed.
1638 *
1639 * Caller must hold RTNL
1640 */
1641void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1642{
1643	struct slave *swap_slave;
1644	struct slave *curr_active;
1645
1646	curr_active = rtnl_dereference(bond->curr_active_slave);
1647	if (curr_active == new_slave)
1648		return;
1649
1650	if (curr_active && bond->alb_info.primary_is_promisc) {
1651		dev_set_promiscuity(curr_active->dev, -1);
1652		bond->alb_info.primary_is_promisc = 0;
1653		bond->alb_info.rlb_promisc_timeout_counter = 0;
1654	}
1655
1656	swap_slave = curr_active;
1657	rcu_assign_pointer(bond->curr_active_slave, new_slave);
1658
1659	if (!new_slave || !bond_has_slaves(bond))
1660		return;
1661
1662	/* set the new curr_active_slave to the bonds mac address
1663	 * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1664	 */
1665	if (!swap_slave)
1666		swap_slave = bond_slave_has_mac(bond, bond->dev->dev_addr);
1667
1668	/* Arrange for swap_slave and new_slave to temporarily be
1669	 * ignored so we can mess with their MAC addresses without
1670	 * fear of interference from transmit activity.
1671	 */
1672	if (swap_slave)
1673		tlb_clear_slave(bond, swap_slave, 1);
1674	tlb_clear_slave(bond, new_slave, 1);
1675
1676	/* in TLB mode, the slave might flip down/up with the old dev_addr,
1677	 * and thus filter bond->dev_addr's packets, so force bond's mac
1678	 */
1679	if (BOND_MODE(bond) == BOND_MODE_TLB) {
1680		struct sockaddr sa;
1681		u8 tmp_addr[ETH_ALEN];
1682
1683		ether_addr_copy(tmp_addr, new_slave->dev->dev_addr);
1684
1685		memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1686		sa.sa_family = bond->dev->type;
1687		/* we don't care if it can't change its mac, best effort */
1688		dev_set_mac_address(new_slave->dev, &sa);
1689
1690		ether_addr_copy(new_slave->dev->dev_addr, tmp_addr);
1691	}
1692
1693	/* curr_active_slave must be set before calling alb_swap_mac_addr */
1694	if (swap_slave) {
1695		/* swap mac address */
1696		alb_swap_mac_addr(swap_slave, new_slave);
1697		alb_fasten_mac_swap(bond, swap_slave, new_slave);
1698	} else {
1699		/* set the new_slave to the bond mac address */
1700		alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1701		alb_send_learning_packets(new_slave, bond->dev->dev_addr,
1702					  false);
1703	}
1704}
1705
1706/* Called with RTNL */
1707int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1708{
1709	struct bonding *bond = netdev_priv(bond_dev);
1710	struct sockaddr *sa = addr;
1711	struct slave *curr_active;
1712	struct slave *swap_slave;
1713	int res;
1714
1715	if (!is_valid_ether_addr(sa->sa_data))
1716		return -EADDRNOTAVAIL;
1717
1718	res = alb_set_mac_address(bond, addr);
1719	if (res)
1720		return res;
1721
1722	memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1723
1724	/* If there is no curr_active_slave there is nothing else to do.
1725	 * Otherwise we'll need to pass the new address to it and handle
1726	 * duplications.
1727	 */
1728	curr_active = rtnl_dereference(bond->curr_active_slave);
1729	if (!curr_active)
1730		return 0;
1731
1732	swap_slave = bond_slave_has_mac(bond, bond_dev->dev_addr);
1733
1734	if (swap_slave) {
1735		alb_swap_mac_addr(swap_slave, curr_active);
1736		alb_fasten_mac_swap(bond, swap_slave, curr_active);
1737	} else {
1738		alb_set_slave_mac_addr(curr_active, bond_dev->dev_addr);
1739
1740		alb_send_learning_packets(curr_active,
1741					  bond_dev->dev_addr, false);
1742		if (bond->alb_info.rlb_enabled) {
1743			/* inform clients mac address has changed */
1744			rlb_req_update_slave_clients(bond, curr_active);
1745		}
1746	}
1747
1748	return 0;
1749}
1750
1751void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1752{
1753	if (bond->alb_info.rlb_enabled)
1754		rlb_clear_vlan(bond, vlan_id);
1755}
1756
1757