bonding: fix enslaving in alb mode when link down
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / net / bonding / bond_alb.c
1 /*
2  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the
6  * Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
11  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * for more details.
13  *
14  * You should have received a copy of the GNU General Public License along
15  * with this program; if not, write to the Free Software Foundation, Inc.,
16  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  */
22
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25 #include <linux/skbuff.h>
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
28 #include <linux/pkt_sched.h>
29 #include <linux/spinlock.h>
30 #include <linux/slab.h>
31 #include <linux/timer.h>
32 #include <linux/ip.h>
33 #include <linux/ipv6.h>
34 #include <linux/if_arp.h>
35 #include <linux/if_ether.h>
36 #include <linux/if_bonding.h>
37 #include <linux/if_vlan.h>
38 #include <linux/in.h>
39 #include <net/ipx.h>
40 #include <net/arp.h>
41 #include <net/ipv6.h>
42 #include <asm/byteorder.h>
43 #include "bonding.h"
44 #include "bond_alb.h"
45
46
47
48 #ifndef __long_aligned
49 #define __long_aligned __attribute__((aligned((sizeof(long)))))
50 #endif
51 static const u8 mac_bcast[ETH_ALEN] __long_aligned = {
52         0xff, 0xff, 0xff, 0xff, 0xff, 0xff
53 };
54 static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = {
55         0x33, 0x33, 0x00, 0x00, 0x00, 0x01
56 };
57 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
58
59 #pragma pack(1)
60 struct learning_pkt {
61         u8 mac_dst[ETH_ALEN];
62         u8 mac_src[ETH_ALEN];
63         __be16 type;
64         u8 padding[ETH_ZLEN - ETH_HLEN];
65 };
66
67 struct arp_pkt {
68         __be16  hw_addr_space;
69         __be16  prot_addr_space;
70         u8      hw_addr_len;
71         u8      prot_addr_len;
72         __be16  op_code;
73         u8      mac_src[ETH_ALEN];      /* sender hardware address */
74         __be32  ip_src;                 /* sender IP address */
75         u8      mac_dst[ETH_ALEN];      /* target hardware address */
76         __be32  ip_dst;                 /* target IP address */
77 };
78 #pragma pack()
79
80 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
81 {
82         return (struct arp_pkt *)skb_network_header(skb);
83 }
84
85 /* Forward declaration */
86 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
87
88 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
89 {
90         int i;
91         u8 hash = 0;
92
93         for (i = 0; i < hash_size; i++) {
94                 hash ^= hash_start[i];
95         }
96
97         return hash;
98 }
99
100 /*********************** tlb specific functions ***************************/
101
102 static inline void _lock_tx_hashtbl_bh(struct bonding *bond)
103 {
104         spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
105 }
106
107 static inline void _unlock_tx_hashtbl_bh(struct bonding *bond)
108 {
109         spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
110 }
111
112 static inline void _lock_tx_hashtbl(struct bonding *bond)
113 {
114         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
115 }
116
117 static inline void _unlock_tx_hashtbl(struct bonding *bond)
118 {
119         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
120 }
121
122 /* Caller must hold tx_hashtbl lock */
123 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
124 {
125         if (save_load) {
126                 entry->load_history = 1 + entry->tx_bytes /
127                                       BOND_TLB_REBALANCE_INTERVAL;
128                 entry->tx_bytes = 0;
129         }
130
131         entry->tx_slave = NULL;
132         entry->next = TLB_NULL_INDEX;
133         entry->prev = TLB_NULL_INDEX;
134 }
135
136 static inline void tlb_init_slave(struct slave *slave)
137 {
138         SLAVE_TLB_INFO(slave).load = 0;
139         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
140 }
141
142 /* Caller must hold bond lock for read, BH disabled */
143 static void __tlb_clear_slave(struct bonding *bond, struct slave *slave,
144                          int save_load)
145 {
146         struct tlb_client_info *tx_hash_table;
147         u32 index;
148
149         /* clear slave from tx_hashtbl */
150         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
151
152         /* skip this if we've already freed the tx hash table */
153         if (tx_hash_table) {
154                 index = SLAVE_TLB_INFO(slave).head;
155                 while (index != TLB_NULL_INDEX) {
156                         u32 next_index = tx_hash_table[index].next;
157                         tlb_init_table_entry(&tx_hash_table[index], save_load);
158                         index = next_index;
159                 }
160         }
161
162         tlb_init_slave(slave);
163 }
164
165 /* Caller must hold bond lock for read */
166 static void tlb_clear_slave(struct bonding *bond, struct slave *slave,
167                          int save_load)
168 {
169         _lock_tx_hashtbl_bh(bond);
170         __tlb_clear_slave(bond, slave, save_load);
171         _unlock_tx_hashtbl_bh(bond);
172 }
173
174 /* Must be called before starting the monitor timer */
175 static int tlb_initialize(struct bonding *bond)
176 {
177         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
178         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
179         struct tlb_client_info *new_hashtbl;
180         int i;
181
182         new_hashtbl = kzalloc(size, GFP_KERNEL);
183         if (!new_hashtbl) {
184                 pr_err("%s: Error: Failed to allocate TLB hash table\n",
185                        bond->dev->name);
186                 return -1;
187         }
188         _lock_tx_hashtbl_bh(bond);
189
190         bond_info->tx_hashtbl = new_hashtbl;
191
192         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
193                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 0);
194         }
195
196         _unlock_tx_hashtbl_bh(bond);
197
198         return 0;
199 }
200
201 /* Must be called only after all slaves have been released */
202 static 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
214 static 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 */
221 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
222 {
223         struct slave *slave, *least_loaded;
224         long long max_gap;
225         int i;
226
227         least_loaded = NULL;
228         max_gap = LLONG_MIN;
229
230         /* Find the slave with the largest gap */
231         bond_for_each_slave(bond, slave, i) {
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
245 static 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
270                         slave_info->head = hash_index;
271                         slave_info->load +=
272                                 hash_table[hash_index].load_history;
273                 }
274         }
275
276         if (assigned_slave) {
277                 hash_table[hash_index].tx_bytes += skb_len;
278         }
279
280         return assigned_slave;
281 }
282
283 /* Caller must hold bond lock for read */
284 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index,
285                                         u32 skb_len)
286 {
287         struct slave *tx_slave;
288         /*
289          * We don't need to disable softirq here, becase
290          * tlb_choose_channel() is only called by bond_alb_xmit()
291          * which already has softirq disabled.
292          */
293         _lock_tx_hashtbl(bond);
294         tx_slave = __tlb_choose_channel(bond, hash_index, skb_len);
295         _unlock_tx_hashtbl(bond);
296         return tx_slave;
297 }
298
299 /*********************** rlb specific functions ***************************/
300 static inline void _lock_rx_hashtbl_bh(struct bonding *bond)
301 {
302         spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
303 }
304
305 static inline void _unlock_rx_hashtbl_bh(struct bonding *bond)
306 {
307         spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
308 }
309
310 static inline void _lock_rx_hashtbl(struct bonding *bond)
311 {
312         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
313 }
314
315 static inline void _unlock_rx_hashtbl(struct bonding *bond)
316 {
317         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
318 }
319
320 /* when an ARP REPLY is received from a client update its info
321  * in the rx_hashtbl
322  */
323 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
324 {
325         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
326         struct rlb_client_info *client_info;
327         u32 hash_index;
328
329         _lock_rx_hashtbl_bh(bond);
330
331         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
332         client_info = &(bond_info->rx_hashtbl[hash_index]);
333
334         if ((client_info->assigned) &&
335             (client_info->ip_src == arp->ip_dst) &&
336             (client_info->ip_dst == arp->ip_src) &&
337             (compare_ether_addr_64bits(client_info->mac_dst, arp->mac_src))) {
338                 /* update the clients MAC address */
339                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
340                 client_info->ntt = 1;
341                 bond_info->rx_ntt = 1;
342         }
343
344         _unlock_rx_hashtbl_bh(bond);
345 }
346
347 static void rlb_arp_recv(struct sk_buff *skb, struct bonding *bond,
348                          struct slave *slave)
349 {
350         struct arp_pkt *arp;
351
352         if (skb->protocol != cpu_to_be16(ETH_P_ARP))
353                 return;
354
355         arp = (struct arp_pkt *) skb->data;
356         if (!arp) {
357                 pr_debug("Packet has no ARP data\n");
358                 return;
359         }
360
361         if (!pskb_may_pull(skb, arp_hdr_len(bond->dev)))
362                 return;
363
364         if (skb->len < sizeof(struct arp_pkt)) {
365                 pr_debug("Packet is too small to be an ARP\n");
366                 return;
367         }
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         }
374 }
375
376 /* Caller must hold bond lock for read */
377 static struct slave *rlb_next_rx_slave(struct bonding *bond)
378 {
379         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
380         struct slave *rx_slave, *slave, *start_at;
381         int i = 0;
382
383         if (bond_info->next_rx_slave) {
384                 start_at = bond_info->next_rx_slave;
385         } else {
386                 start_at = bond->first_slave;
387         }
388
389         rx_slave = NULL;
390
391         bond_for_each_slave_from(bond, slave, i, start_at) {
392                 if (SLAVE_IS_OK(slave)) {
393                         if (!rx_slave) {
394                                 rx_slave = slave;
395                         } else if (slave->speed > rx_slave->speed) {
396                                 rx_slave = slave;
397                         }
398                 }
399         }
400
401         if (rx_slave) {
402                 bond_info->next_rx_slave = rx_slave->next;
403         }
404
405         return rx_slave;
406 }
407
408 /* teach the switch the mac of a disabled slave
409  * on the primary for fault tolerance
410  *
411  * Caller must hold bond->curr_slave_lock for write or bond lock for write
412  */
413 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
414 {
415         if (!bond->curr_active_slave) {
416                 return;
417         }
418
419         if (!bond->alb_info.primary_is_promisc) {
420                 if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
421                         bond->alb_info.primary_is_promisc = 1;
422                 else
423                         bond->alb_info.primary_is_promisc = 0;
424         }
425
426         bond->alb_info.rlb_promisc_timeout_counter = 0;
427
428         alb_send_learning_packets(bond->curr_active_slave, addr);
429 }
430
431 /* slave being removed should not be active at this point
432  *
433  * Caller must hold bond lock for read
434  */
435 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
436 {
437         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
438         struct rlb_client_info *rx_hash_table;
439         u32 index, next_index;
440
441         /* clear slave from rx_hashtbl */
442         _lock_rx_hashtbl_bh(bond);
443
444         rx_hash_table = bond_info->rx_hashtbl;
445         index = bond_info->rx_hashtbl_head;
446         for (; index != RLB_NULL_INDEX; index = next_index) {
447                 next_index = rx_hash_table[index].next;
448                 if (rx_hash_table[index].slave == slave) {
449                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
450
451                         if (assigned_slave) {
452                                 rx_hash_table[index].slave = assigned_slave;
453                                 if (compare_ether_addr_64bits(rx_hash_table[index].mac_dst,
454                                                               mac_bcast)) {
455                                         bond_info->rx_hashtbl[index].ntt = 1;
456                                         bond_info->rx_ntt = 1;
457                                         /* A slave has been removed from the
458                                          * table because it is either disabled
459                                          * or being released. We must retry the
460                                          * update to avoid clients from not
461                                          * being updated & disconnecting when
462                                          * there is stress
463                                          */
464                                         bond_info->rlb_update_retry_counter =
465                                                 RLB_UPDATE_RETRY;
466                                 }
467                         } else {  /* there is no active slave */
468                                 rx_hash_table[index].slave = NULL;
469                         }
470                 }
471         }
472
473         _unlock_rx_hashtbl_bh(bond);
474
475         write_lock_bh(&bond->curr_slave_lock);
476
477         if (slave != bond->curr_active_slave) {
478                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
479         }
480
481         write_unlock_bh(&bond->curr_slave_lock);
482 }
483
484 static void rlb_update_client(struct rlb_client_info *client_info)
485 {
486         int i;
487
488         if (!client_info->slave) {
489                 return;
490         }
491
492         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
493                 struct sk_buff *skb;
494
495                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
496                                  client_info->ip_dst,
497                                  client_info->slave->dev,
498                                  client_info->ip_src,
499                                  client_info->mac_dst,
500                                  client_info->slave->dev->dev_addr,
501                                  client_info->mac_dst);
502                 if (!skb) {
503                         pr_err("%s: Error: failed to create an ARP packet\n",
504                                client_info->slave->dev->master->name);
505                         continue;
506                 }
507
508                 skb->dev = client_info->slave->dev;
509
510                 if (client_info->tag) {
511                         skb = vlan_put_tag(skb, client_info->vlan_id);
512                         if (!skb) {
513                                 pr_err("%s: Error: failed to insert VLAN tag\n",
514                                        client_info->slave->dev->master->name);
515                                 continue;
516                         }
517                 }
518
519                 arp_xmit(skb);
520         }
521 }
522
523 /* sends ARP REPLIES that update the clients that need updating */
524 static void rlb_update_rx_clients(struct bonding *bond)
525 {
526         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
527         struct rlb_client_info *client_info;
528         u32 hash_index;
529
530         _lock_rx_hashtbl_bh(bond);
531
532         hash_index = bond_info->rx_hashtbl_head;
533         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
534                 client_info = &(bond_info->rx_hashtbl[hash_index]);
535                 if (client_info->ntt) {
536                         rlb_update_client(client_info);
537                         if (bond_info->rlb_update_retry_counter == 0) {
538                                 client_info->ntt = 0;
539                         }
540                 }
541         }
542
543         /* do not update the entries again until this counter is zero so that
544          * not to confuse the clients.
545          */
546         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
547
548         _unlock_rx_hashtbl_bh(bond);
549 }
550
551 /* The slave was assigned a new mac address - update the clients */
552 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
553 {
554         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
555         struct rlb_client_info *client_info;
556         int ntt = 0;
557         u32 hash_index;
558
559         _lock_rx_hashtbl_bh(bond);
560
561         hash_index = bond_info->rx_hashtbl_head;
562         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
563                 client_info = &(bond_info->rx_hashtbl[hash_index]);
564
565                 if ((client_info->slave == slave) &&
566                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
567                         client_info->ntt = 1;
568                         ntt = 1;
569                 }
570         }
571
572         // update the team's flag only after the whole iteration
573         if (ntt) {
574                 bond_info->rx_ntt = 1;
575                 //fasten the change
576                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
577         }
578
579         _unlock_rx_hashtbl_bh(bond);
580 }
581
582 /* mark all clients using src_ip to be updated */
583 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
584 {
585         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
586         struct rlb_client_info *client_info;
587         u32 hash_index;
588
589         _lock_rx_hashtbl(bond);
590
591         hash_index = bond_info->rx_hashtbl_head;
592         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
593                 client_info = &(bond_info->rx_hashtbl[hash_index]);
594
595                 if (!client_info->slave) {
596                         pr_err("%s: Error: found a client with no channel in the client's hash table\n",
597                                bond->dev->name);
598                         continue;
599                 }
600                 /*update all clients using this src_ip, that are not assigned
601                  * to the team's address (curr_active_slave) and have a known
602                  * unicast mac address.
603                  */
604                 if ((client_info->ip_src == src_ip) &&
605                     compare_ether_addr_64bits(client_info->slave->dev->dev_addr,
606                            bond->dev->dev_addr) &&
607                     compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
608                         client_info->ntt = 1;
609                         bond_info->rx_ntt = 1;
610                 }
611         }
612
613         _unlock_rx_hashtbl(bond);
614 }
615
616 /* Caller must hold both bond and ptr locks for read */
617 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
618 {
619         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
620         struct arp_pkt *arp = arp_pkt(skb);
621         struct slave *assigned_slave;
622         struct rlb_client_info *client_info;
623         u32 hash_index = 0;
624
625         _lock_rx_hashtbl(bond);
626
627         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_dst));
628         client_info = &(bond_info->rx_hashtbl[hash_index]);
629
630         if (client_info->assigned) {
631                 if ((client_info->ip_src == arp->ip_src) &&
632                     (client_info->ip_dst == arp->ip_dst)) {
633                         /* the entry is already assigned to this client */
634                         if (compare_ether_addr_64bits(arp->mac_dst, mac_bcast)) {
635                                 /* update mac address from arp */
636                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
637                         }
638
639                         assigned_slave = client_info->slave;
640                         if (assigned_slave) {
641                                 _unlock_rx_hashtbl(bond);
642                                 return assigned_slave;
643                         }
644                 } else {
645                         /* the entry is already assigned to some other client,
646                          * move the old client to primary (curr_active_slave) so
647                          * that the new client can be assigned to this entry.
648                          */
649                         if (bond->curr_active_slave &&
650                             client_info->slave != bond->curr_active_slave) {
651                                 client_info->slave = bond->curr_active_slave;
652                                 rlb_update_client(client_info);
653                         }
654                 }
655         }
656         /* assign a new slave */
657         assigned_slave = rlb_next_rx_slave(bond);
658
659         if (assigned_slave) {
660                 client_info->ip_src = arp->ip_src;
661                 client_info->ip_dst = arp->ip_dst;
662                 /* arp->mac_dst is broadcast for arp reqeusts.
663                  * will be updated with clients actual unicast mac address
664                  * upon receiving an arp reply.
665                  */
666                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
667                 client_info->slave = assigned_slave;
668
669                 if (compare_ether_addr_64bits(client_info->mac_dst, mac_bcast)) {
670                         client_info->ntt = 1;
671                         bond->alb_info.rx_ntt = 1;
672                 } else {
673                         client_info->ntt = 0;
674                 }
675
676                 if (bond_vlan_used(bond)) {
677                         if (!vlan_get_tag(skb, &client_info->vlan_id))
678                                 client_info->tag = 1;
679                 }
680
681                 if (!client_info->assigned) {
682                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
683                         bond_info->rx_hashtbl_head = hash_index;
684                         client_info->next = prev_tbl_head;
685                         if (prev_tbl_head != RLB_NULL_INDEX) {
686                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
687                                         hash_index;
688                         }
689                         client_info->assigned = 1;
690                 }
691         }
692
693         _unlock_rx_hashtbl(bond);
694
695         return assigned_slave;
696 }
697
698 /* chooses (and returns) transmit channel for arp reply
699  * does not choose channel for other arp types since they are
700  * sent on the curr_active_slave
701  */
702 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
703 {
704         struct arp_pkt *arp = arp_pkt(skb);
705         struct slave *tx_slave = NULL;
706
707         if (arp->op_code == htons(ARPOP_REPLY)) {
708                 /* the arp must be sent on the selected
709                 * rx channel
710                 */
711                 tx_slave = rlb_choose_channel(skb, bond);
712                 if (tx_slave) {
713                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
714                 }
715                 pr_debug("Server sent ARP Reply packet\n");
716         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
717                 /* Create an entry in the rx_hashtbl for this client as a
718                  * place holder.
719                  * When the arp reply is received the entry will be updated
720                  * with the correct unicast address of the client.
721                  */
722                 rlb_choose_channel(skb, bond);
723
724                 /* The ARP reply packets must be delayed so that
725                  * they can cancel out the influence of the ARP request.
726                  */
727                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
728
729                 /* arp requests are broadcast and are sent on the primary
730                  * the arp request will collapse all clients on the subnet to
731                  * the primary slave. We must register these clients to be
732                  * updated with their assigned mac.
733                  */
734                 rlb_req_update_subnet_clients(bond, arp->ip_src);
735                 pr_debug("Server sent ARP Request packet\n");
736         }
737
738         return tx_slave;
739 }
740
741 /* Caller must hold bond lock for read */
742 static void rlb_rebalance(struct bonding *bond)
743 {
744         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
745         struct slave *assigned_slave;
746         struct rlb_client_info *client_info;
747         int ntt;
748         u32 hash_index;
749
750         _lock_rx_hashtbl_bh(bond);
751
752         ntt = 0;
753         hash_index = bond_info->rx_hashtbl_head;
754         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
755                 client_info = &(bond_info->rx_hashtbl[hash_index]);
756                 assigned_slave = rlb_next_rx_slave(bond);
757                 if (assigned_slave && (client_info->slave != assigned_slave)) {
758                         client_info->slave = assigned_slave;
759                         client_info->ntt = 1;
760                         ntt = 1;
761                 }
762         }
763
764         /* update the team's flag only after the whole iteration */
765         if (ntt) {
766                 bond_info->rx_ntt = 1;
767         }
768         _unlock_rx_hashtbl_bh(bond);
769 }
770
771 /* Caller must hold rx_hashtbl lock */
772 static void rlb_init_table_entry(struct rlb_client_info *entry)
773 {
774         memset(entry, 0, sizeof(struct rlb_client_info));
775         entry->next = RLB_NULL_INDEX;
776         entry->prev = RLB_NULL_INDEX;
777 }
778
779 static int rlb_initialize(struct bonding *bond)
780 {
781         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
782         struct rlb_client_info  *new_hashtbl;
783         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
784         int i;
785
786         new_hashtbl = kmalloc(size, GFP_KERNEL);
787         if (!new_hashtbl) {
788                 pr_err("%s: Error: Failed to allocate RLB hash table\n",
789                        bond->dev->name);
790                 return -1;
791         }
792         _lock_rx_hashtbl_bh(bond);
793
794         bond_info->rx_hashtbl = new_hashtbl;
795
796         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
797
798         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
799                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
800         }
801
802         _unlock_rx_hashtbl_bh(bond);
803
804         /* register to receive ARPs */
805         bond->recv_probe = rlb_arp_recv;
806
807         return 0;
808 }
809
810 static void rlb_deinitialize(struct bonding *bond)
811 {
812         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
813
814         _lock_rx_hashtbl_bh(bond);
815
816         kfree(bond_info->rx_hashtbl);
817         bond_info->rx_hashtbl = NULL;
818         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
819
820         _unlock_rx_hashtbl_bh(bond);
821 }
822
823 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
824 {
825         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
826         u32 curr_index;
827
828         _lock_rx_hashtbl_bh(bond);
829
830         curr_index = bond_info->rx_hashtbl_head;
831         while (curr_index != RLB_NULL_INDEX) {
832                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
833                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
834                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
835
836                 if (curr->tag && (curr->vlan_id == vlan_id)) {
837                         if (curr_index == bond_info->rx_hashtbl_head) {
838                                 bond_info->rx_hashtbl_head = next_index;
839                         }
840                         if (prev_index != RLB_NULL_INDEX) {
841                                 bond_info->rx_hashtbl[prev_index].next = next_index;
842                         }
843                         if (next_index != RLB_NULL_INDEX) {
844                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
845                         }
846
847                         rlb_init_table_entry(curr);
848                 }
849
850                 curr_index = next_index;
851         }
852
853         _unlock_rx_hashtbl_bh(bond);
854 }
855
856 /*********************** tlb/rlb shared functions *********************/
857
858 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
859 {
860         struct bonding *bond = bond_get_bond_by_slave(slave);
861         struct learning_pkt pkt;
862         int size = sizeof(struct learning_pkt);
863         int i;
864
865         memset(&pkt, 0, size);
866         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
867         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
868         pkt.type = cpu_to_be16(ETH_P_LOOP);
869
870         for (i = 0; i < MAX_LP_BURST; i++) {
871                 struct sk_buff *skb;
872                 char *data;
873
874                 skb = dev_alloc_skb(size);
875                 if (!skb) {
876                         return;
877                 }
878
879                 data = skb_put(skb, size);
880                 memcpy(data, &pkt, size);
881
882                 skb_reset_mac_header(skb);
883                 skb->network_header = skb->mac_header + ETH_HLEN;
884                 skb->protocol = pkt.type;
885                 skb->priority = TC_PRIO_CONTROL;
886                 skb->dev = slave->dev;
887
888                 if (bond_vlan_used(bond)) {
889                         struct vlan_entry *vlan;
890
891                         vlan = bond_next_vlan(bond,
892                                               bond->alb_info.current_alb_vlan);
893
894                         bond->alb_info.current_alb_vlan = vlan;
895                         if (!vlan) {
896                                 kfree_skb(skb);
897                                 continue;
898                         }
899
900                         skb = vlan_put_tag(skb, vlan->vlan_id);
901                         if (!skb) {
902                                 pr_err("%s: Error: failed to insert VLAN tag\n",
903                                        bond->dev->name);
904                                 continue;
905                         }
906                 }
907
908                 dev_queue_xmit(skb);
909         }
910 }
911
912 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
913 {
914         struct net_device *dev = slave->dev;
915         struct sockaddr s_addr;
916
917         if (slave->bond->params.mode == BOND_MODE_TLB) {
918                 memcpy(dev->dev_addr, addr, dev->addr_len);
919                 return 0;
920         }
921
922         /* for rlb each slave must have a unique hw mac addresses so that */
923         /* each slave will receive packets destined to a different mac */
924         memcpy(s_addr.sa_data, addr, dev->addr_len);
925         s_addr.sa_family = dev->type;
926         if (dev_set_mac_address(dev, &s_addr)) {
927                 pr_err("%s: Error: dev_set_mac_address of dev %s failed!\n"
928                        "ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
929                        dev->master->name, dev->name);
930                 return -EOPNOTSUPP;
931         }
932         return 0;
933 }
934
935 /*
936  * Swap MAC addresses between two slaves.
937  *
938  * Called with RTNL held, and no other locks.
939  *
940  */
941
942 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
943 {
944         u8 tmp_mac_addr[ETH_ALEN];
945
946         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
947         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr);
948         alb_set_slave_mac_addr(slave2, tmp_mac_addr);
949
950 }
951
952 /*
953  * Send learning packets after MAC address swap.
954  *
955  * Called with RTNL and no other locks
956  */
957 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
958                                 struct slave *slave2)
959 {
960         int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
961         struct slave *disabled_slave = NULL;
962
963         ASSERT_RTNL();
964
965         /* fasten the change in the switch */
966         if (SLAVE_IS_OK(slave1)) {
967                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
968                 if (bond->alb_info.rlb_enabled) {
969                         /* inform the clients that the mac address
970                          * has changed
971                          */
972                         rlb_req_update_slave_clients(bond, slave1);
973                 }
974         } else {
975                 disabled_slave = slave1;
976         }
977
978         if (SLAVE_IS_OK(slave2)) {
979                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
980                 if (bond->alb_info.rlb_enabled) {
981                         /* inform the clients that the mac address
982                          * has changed
983                          */
984                         rlb_req_update_slave_clients(bond, slave2);
985                 }
986         } else {
987                 disabled_slave = slave2;
988         }
989
990         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
991                 /* A disabled slave was assigned an active mac addr */
992                 rlb_teach_disabled_mac_on_primary(bond,
993                                                   disabled_slave->dev->dev_addr);
994         }
995 }
996
997 /**
998  * alb_change_hw_addr_on_detach
999  * @bond: bonding we're working on
1000  * @slave: the slave that was just detached
1001  *
1002  * We assume that @slave was already detached from the slave list.
1003  *
1004  * If @slave's permanent hw address is different both from its current
1005  * address and from @bond's address, then somewhere in the bond there's
1006  * a slave that has @slave's permanet address as its current address.
1007  * We'll make sure that that slave no longer uses @slave's permanent address.
1008  *
1009  * Caller must hold RTNL and no other locks
1010  */
1011 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1012 {
1013         int perm_curr_diff;
1014         int perm_bond_diff;
1015
1016         perm_curr_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1017                                                    slave->dev->dev_addr);
1018         perm_bond_diff = compare_ether_addr_64bits(slave->perm_hwaddr,
1019                                                    bond->dev->dev_addr);
1020
1021         if (perm_curr_diff && perm_bond_diff) {
1022                 struct slave *tmp_slave;
1023                 int i, found = 0;
1024
1025                 bond_for_each_slave(bond, tmp_slave, i) {
1026                         if (!compare_ether_addr_64bits(slave->perm_hwaddr,
1027                                                        tmp_slave->dev->dev_addr)) {
1028                                 found = 1;
1029                                 break;
1030                         }
1031                 }
1032
1033                 if (found) {
1034                         /* locking: needs RTNL and nothing else */
1035                         alb_swap_mac_addr(bond, slave, tmp_slave);
1036                         alb_fasten_mac_swap(bond, slave, tmp_slave);
1037                 }
1038         }
1039 }
1040
1041 /**
1042  * alb_handle_addr_collision_on_attach
1043  * @bond: bonding we're working on
1044  * @slave: the slave that was just attached
1045  *
1046  * checks uniqueness of slave's mac address and handles the case the
1047  * new slave uses the bonds mac address.
1048  *
1049  * If the permanent hw address of @slave is @bond's hw address, we need to
1050  * find a different hw address to give @slave, that isn't in use by any other
1051  * slave in the bond. This address must be, of course, one of the permanent
1052  * addresses of the other slaves.
1053  *
1054  * We go over the slave list, and for each slave there we compare its
1055  * permanent hw address with the current address of all the other slaves.
1056  * If no match was found, then we've found a slave with a permanent address
1057  * that isn't used by any other slave in the bond, so we can assign it to
1058  * @slave.
1059  *
1060  * assumption: this function is called before @slave is attached to the
1061  *             bond slave list.
1062  *
1063  * caller must hold the bond lock for write since the mac addresses are compared
1064  * and may be swapped.
1065  */
1066 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1067 {
1068         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1069         struct slave *has_bond_addr = bond->curr_active_slave;
1070         int i, j, found = 0;
1071
1072         if (bond->slave_cnt == 0) {
1073                 /* this is the first slave */
1074                 return 0;
1075         }
1076
1077         /* if slave's mac address differs from bond's mac address
1078          * check uniqueness of slave's mac address against the other
1079          * slaves in the bond.
1080          */
1081         if (compare_ether_addr_64bits(slave->perm_hwaddr, bond->dev->dev_addr)) {
1082                 bond_for_each_slave(bond, tmp_slave1, i) {
1083                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1084                                                        slave->dev->dev_addr)) {
1085                                 found = 1;
1086                                 break;
1087                         }
1088                 }
1089
1090                 if (!found)
1091                         return 0;
1092
1093                 /* Try setting slave mac to bond address and fall-through
1094                    to code handling that situation below... */
1095                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr);
1096         }
1097
1098         /* The slave's address is equal to the address of the bond.
1099          * Search for a spare address in the bond for this slave.
1100          */
1101         free_mac_slave = NULL;
1102
1103         bond_for_each_slave(bond, tmp_slave1, i) {
1104                 found = 0;
1105                 bond_for_each_slave(bond, tmp_slave2, j) {
1106                         if (!compare_ether_addr_64bits(tmp_slave1->perm_hwaddr,
1107                                                        tmp_slave2->dev->dev_addr)) {
1108                                 found = 1;
1109                                 break;
1110                         }
1111                 }
1112
1113                 if (!found) {
1114                         /* no slave has tmp_slave1's perm addr
1115                          * as its curr addr
1116                          */
1117                         free_mac_slave = tmp_slave1;
1118                         break;
1119                 }
1120
1121                 if (!has_bond_addr) {
1122                         if (!compare_ether_addr_64bits(tmp_slave1->dev->dev_addr,
1123                                                        bond->dev->dev_addr)) {
1124
1125                                 has_bond_addr = tmp_slave1;
1126                         }
1127                 }
1128         }
1129
1130         if (free_mac_slave) {
1131                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr);
1132
1133                 pr_warning("%s: Warning: the hw address of slave %s is in use by the bond; giving it the hw address of %s\n",
1134                            bond->dev->name, slave->dev->name,
1135                            free_mac_slave->dev->name);
1136
1137         } else if (has_bond_addr) {
1138                 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",
1139                        bond->dev->name, slave->dev->name);
1140                 return -EFAULT;
1141         }
1142
1143         return 0;
1144 }
1145
1146 /**
1147  * alb_set_mac_address
1148  * @bond:
1149  * @addr:
1150  *
1151  * In TLB mode all slaves are configured to the bond's hw address, but set
1152  * their dev_addr field to different addresses (based on their permanent hw
1153  * addresses).
1154  *
1155  * For each slave, this function sets the interface to the new address and then
1156  * changes its dev_addr field to its previous value.
1157  *
1158  * Unwinding assumes bond's mac address has not yet changed.
1159  */
1160 static int alb_set_mac_address(struct bonding *bond, void *addr)
1161 {
1162         struct sockaddr sa;
1163         struct slave *slave, *stop_at;
1164         char tmp_addr[ETH_ALEN];
1165         int res;
1166         int i;
1167
1168         if (bond->alb_info.rlb_enabled) {
1169                 return 0;
1170         }
1171
1172         bond_for_each_slave(bond, slave, i) {
1173                 /* save net_device's current hw address */
1174                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1175
1176                 res = dev_set_mac_address(slave->dev, addr);
1177
1178                 /* restore net_device's hw address */
1179                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1180
1181                 if (res)
1182                         goto unwind;
1183         }
1184
1185         return 0;
1186
1187 unwind:
1188         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1189         sa.sa_family = bond->dev->type;
1190
1191         /* unwind from head to the slave that failed */
1192         stop_at = slave;
1193         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1194                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1195                 dev_set_mac_address(slave->dev, &sa);
1196                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1197         }
1198
1199         return res;
1200 }
1201
1202 /************************ exported alb funcions ************************/
1203
1204 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1205 {
1206         int res;
1207
1208         res = tlb_initialize(bond);
1209         if (res) {
1210                 return res;
1211         }
1212
1213         if (rlb_enabled) {
1214                 bond->alb_info.rlb_enabled = 1;
1215                 /* initialize rlb */
1216                 res = rlb_initialize(bond);
1217                 if (res) {
1218                         tlb_deinitialize(bond);
1219                         return res;
1220                 }
1221         } else {
1222                 bond->alb_info.rlb_enabled = 0;
1223         }
1224
1225         return 0;
1226 }
1227
1228 void bond_alb_deinitialize(struct bonding *bond)
1229 {
1230         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1231
1232         tlb_deinitialize(bond);
1233
1234         if (bond_info->rlb_enabled) {
1235                 rlb_deinitialize(bond);
1236         }
1237 }
1238
1239 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1240 {
1241         struct bonding *bond = netdev_priv(bond_dev);
1242         struct ethhdr *eth_data;
1243         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1244         struct slave *tx_slave = NULL;
1245         static const __be32 ip_bcast = htonl(0xffffffff);
1246         int hash_size = 0;
1247         int do_tx_balance = 1;
1248         u32 hash_index = 0;
1249         const u8 *hash_start = NULL;
1250         int res = 1;
1251         struct ipv6hdr *ip6hdr;
1252
1253         skb_reset_mac_header(skb);
1254         eth_data = eth_hdr(skb);
1255
1256         /* make sure that the curr_active_slave do not change during tx
1257          */
1258         read_lock(&bond->curr_slave_lock);
1259
1260         switch (ntohs(skb->protocol)) {
1261         case ETH_P_IP: {
1262                 const struct iphdr *iph = ip_hdr(skb);
1263
1264                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast) ||
1265                     (iph->daddr == ip_bcast) ||
1266                     (iph->protocol == IPPROTO_IGMP)) {
1267                         do_tx_balance = 0;
1268                         break;
1269                 }
1270                 hash_start = (char *)&(iph->daddr);
1271                 hash_size = sizeof(iph->daddr);
1272         }
1273                 break;
1274         case ETH_P_IPV6:
1275                 /* IPv6 doesn't really use broadcast mac address, but leave
1276                  * that here just in case.
1277                  */
1278                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_bcast)) {
1279                         do_tx_balance = 0;
1280                         break;
1281                 }
1282
1283                 /* IPv6 uses all-nodes multicast as an equivalent to
1284                  * broadcasts in IPv4.
1285                  */
1286                 if (!compare_ether_addr_64bits(eth_data->h_dest, mac_v6_allmcast)) {
1287                         do_tx_balance = 0;
1288                         break;
1289                 }
1290
1291                 /* Additianally, DAD probes should not be tx-balanced as that
1292                  * will lead to false positives for duplicate addresses and
1293                  * prevent address configuration from working.
1294                  */
1295                 ip6hdr = ipv6_hdr(skb);
1296                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1297                         do_tx_balance = 0;
1298                         break;
1299                 }
1300
1301                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1302                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1303                 break;
1304         case ETH_P_IPX:
1305                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1306                         /* something is wrong with this packet */
1307                         do_tx_balance = 0;
1308                         break;
1309                 }
1310
1311                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1312                         /* The only protocol worth balancing in
1313                          * this family since it has an "ARP" like
1314                          * mechanism
1315                          */
1316                         do_tx_balance = 0;
1317                         break;
1318                 }
1319
1320                 hash_start = (char*)eth_data->h_dest;
1321                 hash_size = ETH_ALEN;
1322                 break;
1323         case ETH_P_ARP:
1324                 do_tx_balance = 0;
1325                 if (bond_info->rlb_enabled) {
1326                         tx_slave = rlb_arp_xmit(skb, bond);
1327                 }
1328                 break;
1329         default:
1330                 do_tx_balance = 0;
1331                 break;
1332         }
1333
1334         if (do_tx_balance) {
1335                 hash_index = _simple_hash(hash_start, hash_size);
1336                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1337         }
1338
1339         if (!tx_slave) {
1340                 /* unbalanced or unassigned, send through primary */
1341                 tx_slave = bond->curr_active_slave;
1342                 bond_info->unbalanced_load += skb->len;
1343         }
1344
1345         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1346                 if (tx_slave != bond->curr_active_slave) {
1347                         memcpy(eth_data->h_source,
1348                                tx_slave->dev->dev_addr,
1349                                ETH_ALEN);
1350                 }
1351
1352                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1353         } else {
1354                 if (tx_slave) {
1355                         _lock_tx_hashtbl(bond);
1356                         __tlb_clear_slave(bond, tx_slave, 0);
1357                         _unlock_tx_hashtbl(bond);
1358                 }
1359         }
1360
1361         if (res) {
1362                 /* no suitable interface, frame not sent */
1363                 dev_kfree_skb(skb);
1364         }
1365         read_unlock(&bond->curr_slave_lock);
1366
1367         return NETDEV_TX_OK;
1368 }
1369
1370 void bond_alb_monitor(struct work_struct *work)
1371 {
1372         struct bonding *bond = container_of(work, struct bonding,
1373                                             alb_work.work);
1374         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1375         struct slave *slave;
1376         int i;
1377
1378         read_lock(&bond->lock);
1379
1380         if (bond->slave_cnt == 0) {
1381                 bond_info->tx_rebalance_counter = 0;
1382                 bond_info->lp_counter = 0;
1383                 goto re_arm;
1384         }
1385
1386         bond_info->tx_rebalance_counter++;
1387         bond_info->lp_counter++;
1388
1389         /* send learning packets */
1390         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1391                 /* change of curr_active_slave involves swapping of mac addresses.
1392                  * in order to avoid this swapping from happening while
1393                  * sending the learning packets, the curr_slave_lock must be held for
1394                  * read.
1395                  */
1396                 read_lock(&bond->curr_slave_lock);
1397
1398                 bond_for_each_slave(bond, slave, i) {
1399                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1400                 }
1401
1402                 read_unlock(&bond->curr_slave_lock);
1403
1404                 bond_info->lp_counter = 0;
1405         }
1406
1407         /* rebalance tx traffic */
1408         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1409
1410                 read_lock(&bond->curr_slave_lock);
1411
1412                 bond_for_each_slave(bond, slave, i) {
1413                         tlb_clear_slave(bond, slave, 1);
1414                         if (slave == bond->curr_active_slave) {
1415                                 SLAVE_TLB_INFO(slave).load =
1416                                         bond_info->unbalanced_load /
1417                                                 BOND_TLB_REBALANCE_INTERVAL;
1418                                 bond_info->unbalanced_load = 0;
1419                         }
1420                 }
1421
1422                 read_unlock(&bond->curr_slave_lock);
1423
1424                 bond_info->tx_rebalance_counter = 0;
1425         }
1426
1427         /* handle rlb stuff */
1428         if (bond_info->rlb_enabled) {
1429                 if (bond_info->primary_is_promisc &&
1430                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1431
1432                         /*
1433                          * dev_set_promiscuity requires rtnl and
1434                          * nothing else.  Avoid race with bond_close.
1435                          */
1436                         read_unlock(&bond->lock);
1437                         if (!rtnl_trylock()) {
1438                                 read_lock(&bond->lock);
1439                                 goto re_arm;
1440                         }
1441
1442                         bond_info->rlb_promisc_timeout_counter = 0;
1443
1444                         /* If the primary was set to promiscuous mode
1445                          * because a slave was disabled then
1446                          * it can now leave promiscuous mode.
1447                          */
1448                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1449                         bond_info->primary_is_promisc = 0;
1450
1451                         rtnl_unlock();
1452                         read_lock(&bond->lock);
1453                 }
1454
1455                 if (bond_info->rlb_rebalance) {
1456                         bond_info->rlb_rebalance = 0;
1457                         rlb_rebalance(bond);
1458                 }
1459
1460                 /* check if clients need updating */
1461                 if (bond_info->rx_ntt) {
1462                         if (bond_info->rlb_update_delay_counter) {
1463                                 --bond_info->rlb_update_delay_counter;
1464                         } else {
1465                                 rlb_update_rx_clients(bond);
1466                                 if (bond_info->rlb_update_retry_counter) {
1467                                         --bond_info->rlb_update_retry_counter;
1468                                 } else {
1469                                         bond_info->rx_ntt = 0;
1470                                 }
1471                         }
1472                 }
1473         }
1474
1475 re_arm:
1476         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1477
1478         read_unlock(&bond->lock);
1479 }
1480
1481 /* assumption: called before the slave is attached to the bond
1482  * and not locked by the bond lock
1483  */
1484 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1485 {
1486         int res;
1487
1488         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr);
1489         if (res) {
1490                 return res;
1491         }
1492
1493         /* caller must hold the bond lock for write since the mac addresses
1494          * are compared and may be swapped.
1495          */
1496         read_lock(&bond->lock);
1497
1498         res = alb_handle_addr_collision_on_attach(bond, slave);
1499
1500         read_unlock(&bond->lock);
1501
1502         if (res) {
1503                 return res;
1504         }
1505
1506         tlb_init_slave(slave);
1507
1508         /* order a rebalance ASAP */
1509         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1510
1511         if (bond->alb_info.rlb_enabled) {
1512                 bond->alb_info.rlb_rebalance = 1;
1513         }
1514
1515         return 0;
1516 }
1517
1518 /*
1519  * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1520  * if necessary.
1521  *
1522  * Caller must hold RTNL and no other locks
1523  */
1524 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1525 {
1526         if (bond->slave_cnt > 1) {
1527                 alb_change_hw_addr_on_detach(bond, slave);
1528         }
1529
1530         tlb_clear_slave(bond, slave, 0);
1531
1532         if (bond->alb_info.rlb_enabled) {
1533                 bond->alb_info.next_rx_slave = NULL;
1534                 rlb_clear_slave(bond, slave);
1535         }
1536 }
1537
1538 /* Caller must hold bond lock for read */
1539 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1540 {
1541         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1542
1543         if (link == BOND_LINK_DOWN) {
1544                 tlb_clear_slave(bond, slave, 0);
1545                 if (bond->alb_info.rlb_enabled) {
1546                         rlb_clear_slave(bond, slave);
1547                 }
1548         } else if (link == BOND_LINK_UP) {
1549                 /* order a rebalance ASAP */
1550                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1551                 if (bond->alb_info.rlb_enabled) {
1552                         bond->alb_info.rlb_rebalance = 1;
1553                         /* If the updelay module parameter is smaller than the
1554                          * forwarding delay of the switch the rebalance will
1555                          * not work because the rebalance arp replies will
1556                          * not be forwarded to the clients..
1557                          */
1558                 }
1559         }
1560 }
1561
1562 /**
1563  * bond_alb_handle_active_change - assign new curr_active_slave
1564  * @bond: our bonding struct
1565  * @new_slave: new slave to assign
1566  *
1567  * Set the bond->curr_active_slave to @new_slave and handle
1568  * mac address swapping and promiscuity changes as needed.
1569  *
1570  * If new_slave is NULL, caller must hold curr_slave_lock or
1571  * bond->lock for write.
1572  *
1573  * If new_slave is not NULL, caller must hold RTNL, bond->lock for
1574  * read and curr_slave_lock for write.  Processing here may sleep, so
1575  * no other locks may be held.
1576  */
1577 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1578         __releases(&bond->curr_slave_lock)
1579         __releases(&bond->lock)
1580         __acquires(&bond->lock)
1581         __acquires(&bond->curr_slave_lock)
1582 {
1583         struct slave *swap_slave;
1584         int i;
1585
1586         if (bond->curr_active_slave == new_slave) {
1587                 return;
1588         }
1589
1590         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1591                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1592                 bond->alb_info.primary_is_promisc = 0;
1593                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1594         }
1595
1596         swap_slave = bond->curr_active_slave;
1597         bond->curr_active_slave = new_slave;
1598
1599         if (!new_slave || (bond->slave_cnt == 0)) {
1600                 return;
1601         }
1602
1603         /* set the new curr_active_slave to the bonds mac address
1604          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1605          */
1606         if (!swap_slave) {
1607                 struct slave *tmp_slave;
1608                 /* find slave that is holding the bond's mac address */
1609                 bond_for_each_slave(bond, tmp_slave, i) {
1610                         if (!compare_ether_addr_64bits(tmp_slave->dev->dev_addr,
1611                                                        bond->dev->dev_addr)) {
1612                                 swap_slave = tmp_slave;
1613                                 break;
1614                         }
1615                 }
1616         }
1617
1618         /*
1619          * Arrange for swap_slave and new_slave to temporarily be
1620          * ignored so we can mess with their MAC addresses without
1621          * fear of interference from transmit activity.
1622          */
1623         if (swap_slave) {
1624                 tlb_clear_slave(bond, swap_slave, 1);
1625         }
1626         tlb_clear_slave(bond, new_slave, 1);
1627
1628         write_unlock_bh(&bond->curr_slave_lock);
1629         read_unlock(&bond->lock);
1630
1631         ASSERT_RTNL();
1632
1633         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1634         if (swap_slave) {
1635                 /* swap mac address */
1636                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1637         } else {
1638                 /* set the new_slave to the bond mac address */
1639                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr);
1640         }
1641
1642         if (swap_slave) {
1643                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1644                 read_lock(&bond->lock);
1645         } else {
1646                 read_lock(&bond->lock);
1647                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1648         }
1649
1650         write_lock_bh(&bond->curr_slave_lock);
1651 }
1652
1653 /*
1654  * Called with RTNL
1655  */
1656 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1657         __acquires(&bond->lock)
1658         __releases(&bond->lock)
1659 {
1660         struct bonding *bond = netdev_priv(bond_dev);
1661         struct sockaddr *sa = addr;
1662         struct slave *slave, *swap_slave;
1663         int res;
1664         int i;
1665
1666         if (!is_valid_ether_addr(sa->sa_data)) {
1667                 return -EADDRNOTAVAIL;
1668         }
1669
1670         res = alb_set_mac_address(bond, addr);
1671         if (res) {
1672                 return res;
1673         }
1674
1675         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1676
1677         /* If there is no curr_active_slave there is nothing else to do.
1678          * Otherwise we'll need to pass the new address to it and handle
1679          * duplications.
1680          */
1681         if (!bond->curr_active_slave) {
1682                 return 0;
1683         }
1684
1685         swap_slave = NULL;
1686
1687         bond_for_each_slave(bond, slave, i) {
1688                 if (!compare_ether_addr_64bits(slave->dev->dev_addr,
1689                                                bond_dev->dev_addr)) {
1690                         swap_slave = slave;
1691                         break;
1692                 }
1693         }
1694
1695         if (swap_slave) {
1696                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1697                 alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1698         } else {
1699                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr);
1700
1701                 read_lock(&bond->lock);
1702                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1703                 if (bond->alb_info.rlb_enabled) {
1704                         /* inform clients mac address has changed */
1705                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1706                 }
1707                 read_unlock(&bond->lock);
1708         }
1709
1710         return 0;
1711 }
1712
1713 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1714 {
1715         if (bond->alb_info.current_alb_vlan &&
1716             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1717                 bond->alb_info.current_alb_vlan = NULL;
1718         }
1719
1720         if (bond->alb_info.rlb_enabled) {
1721                 rlb_clear_vlan(bond, vlan_id);
1722         }
1723 }
1724