Merge branch 'upstream' into topic/asoc
[linux-2.6] / 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 BONDING_DEBUG 1
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 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
48 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
49                                          * Used for division - never set
50                                          * to zero !!!
51                                          */
52 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
53                                          * learning packets to the switch
54                                          */
55
56 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
57                                   * ALB_TIMER_TICKS_PER_SEC)
58
59 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
60                            * ALB_TIMER_TICKS_PER_SEC)
61
62 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
63                                  * Note that this value MUST NOT be smaller
64                                  * because the key hash table is BYTE wide !
65                                  */
66
67
68 #define TLB_NULL_INDEX          0xffffffff
69 #define MAX_LP_BURST            3
70
71 /* rlb defs */
72 #define RLB_HASH_TABLE_SIZE     256
73 #define RLB_NULL_INDEX          0xffffffff
74 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
75 #define RLB_ARP_BURST_SIZE      2
76 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
77                                          * rebalance interval (5 min).
78                                          */
79 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
80  * promiscuous after failover
81  */
82 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
83
84 static const u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
85 static const u8 mac_v6_allmcast[ETH_ALEN] = {0x33,0x33,0x00,0x00,0x00,0x01};
86 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
87
88 #pragma pack(1)
89 struct learning_pkt {
90         u8 mac_dst[ETH_ALEN];
91         u8 mac_src[ETH_ALEN];
92         __be16 type;
93         u8 padding[ETH_ZLEN - ETH_HLEN];
94 };
95
96 struct arp_pkt {
97         __be16  hw_addr_space;
98         __be16  prot_addr_space;
99         u8      hw_addr_len;
100         u8      prot_addr_len;
101         __be16  op_code;
102         u8      mac_src[ETH_ALEN];      /* sender hardware address */
103         __be32  ip_src;                 /* sender IP address */
104         u8      mac_dst[ETH_ALEN];      /* target hardware address */
105         __be32  ip_dst;                 /* target IP address */
106 };
107 #pragma pack()
108
109 static inline struct arp_pkt *arp_pkt(const struct sk_buff *skb)
110 {
111         return (struct arp_pkt *)skb_network_header(skb);
112 }
113
114 /* Forward declaration */
115 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
116
117 static inline u8 _simple_hash(const u8 *hash_start, int hash_size)
118 {
119         int i;
120         u8 hash = 0;
121
122         for (i = 0; i < hash_size; i++) {
123                 hash ^= hash_start[i];
124         }
125
126         return hash;
127 }
128
129 /*********************** tlb specific functions ***************************/
130
131 static inline void _lock_tx_hashtbl(struct bonding *bond)
132 {
133         spin_lock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
134 }
135
136 static inline void _unlock_tx_hashtbl(struct bonding *bond)
137 {
138         spin_unlock_bh(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
139 }
140
141 /* Caller must hold tx_hashtbl lock */
142 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
143 {
144         if (save_load) {
145                 entry->load_history = 1 + entry->tx_bytes /
146                                       BOND_TLB_REBALANCE_INTERVAL;
147                 entry->tx_bytes = 0;
148         }
149
150         entry->tx_slave = NULL;
151         entry->next = TLB_NULL_INDEX;
152         entry->prev = TLB_NULL_INDEX;
153 }
154
155 static inline void tlb_init_slave(struct slave *slave)
156 {
157         SLAVE_TLB_INFO(slave).load = 0;
158         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
159 }
160
161 /* Caller must hold bond lock for read */
162 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
163 {
164         struct tlb_client_info *tx_hash_table;
165         u32 index;
166
167         _lock_tx_hashtbl(bond);
168
169         /* clear slave from tx_hashtbl */
170         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
171
172         /* skip this if we've already freed the tx hash table */
173         if (tx_hash_table) {
174                 index = SLAVE_TLB_INFO(slave).head;
175                 while (index != TLB_NULL_INDEX) {
176                         u32 next_index = tx_hash_table[index].next;
177                         tlb_init_table_entry(&tx_hash_table[index], save_load);
178                         index = next_index;
179                 }
180         }
181
182         tlb_init_slave(slave);
183
184         _unlock_tx_hashtbl(bond);
185 }
186
187 /* Must be called before starting the monitor timer */
188 static int tlb_initialize(struct bonding *bond)
189 {
190         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
191         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
192         struct tlb_client_info *new_hashtbl;
193         int i;
194
195         spin_lock_init(&(bond_info->tx_hashtbl_lock));
196
197         new_hashtbl = kzalloc(size, GFP_KERNEL);
198         if (!new_hashtbl) {
199                 printk(KERN_ERR DRV_NAME
200                        ": %s: Error: Failed to allocate TLB hash table\n",
201                        bond->dev->name);
202                 return -1;
203         }
204         _lock_tx_hashtbl(bond);
205
206         bond_info->tx_hashtbl = new_hashtbl;
207
208         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
209                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
210         }
211
212         _unlock_tx_hashtbl(bond);
213
214         return 0;
215 }
216
217 /* Must be called only after all slaves have been released */
218 static void tlb_deinitialize(struct bonding *bond)
219 {
220         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
221
222         _lock_tx_hashtbl(bond);
223
224         kfree(bond_info->tx_hashtbl);
225         bond_info->tx_hashtbl = NULL;
226
227         _unlock_tx_hashtbl(bond);
228 }
229
230 /* Caller must hold bond lock for read */
231 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
232 {
233         struct slave *slave, *least_loaded;
234         s64 max_gap;
235         int i, found = 0;
236
237         /* Find the first enabled slave */
238         bond_for_each_slave(bond, slave, i) {
239                 if (SLAVE_IS_OK(slave)) {
240                         found = 1;
241                         break;
242                 }
243         }
244
245         if (!found) {
246                 return NULL;
247         }
248
249         least_loaded = slave;
250         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
251                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
252
253         /* Find the slave with the largest gap */
254         bond_for_each_slave_from(bond, slave, i, least_loaded) {
255                 if (SLAVE_IS_OK(slave)) {
256                         s64 gap = (s64)(slave->speed << 20) -
257                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
258                         if (max_gap < gap) {
259                                 least_loaded = slave;
260                                 max_gap = gap;
261                         }
262                 }
263         }
264
265         return least_loaded;
266 }
267
268 /* Caller must hold bond lock for read */
269 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
270 {
271         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
272         struct tlb_client_info *hash_table;
273         struct slave *assigned_slave;
274
275         _lock_tx_hashtbl(bond);
276
277         hash_table = bond_info->tx_hashtbl;
278         assigned_slave = hash_table[hash_index].tx_slave;
279         if (!assigned_slave) {
280                 assigned_slave = tlb_get_least_loaded_slave(bond);
281
282                 if (assigned_slave) {
283                         struct tlb_slave_info *slave_info =
284                                 &(SLAVE_TLB_INFO(assigned_slave));
285                         u32 next_index = slave_info->head;
286
287                         hash_table[hash_index].tx_slave = assigned_slave;
288                         hash_table[hash_index].next = next_index;
289                         hash_table[hash_index].prev = TLB_NULL_INDEX;
290
291                         if (next_index != TLB_NULL_INDEX) {
292                                 hash_table[next_index].prev = hash_index;
293                         }
294
295                         slave_info->head = hash_index;
296                         slave_info->load +=
297                                 hash_table[hash_index].load_history;
298                 }
299         }
300
301         if (assigned_slave) {
302                 hash_table[hash_index].tx_bytes += skb_len;
303         }
304
305         _unlock_tx_hashtbl(bond);
306
307         return assigned_slave;
308 }
309
310 /*********************** rlb specific functions ***************************/
311 static inline void _lock_rx_hashtbl(struct bonding *bond)
312 {
313         spin_lock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
314 }
315
316 static inline void _unlock_rx_hashtbl(struct bonding *bond)
317 {
318         spin_unlock_bh(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
319 }
320
321 /* when an ARP REPLY is received from a client update its info
322  * in the rx_hashtbl
323  */
324 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
325 {
326         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
327         struct rlb_client_info *client_info;
328         u32 hash_index;
329
330         _lock_rx_hashtbl(bond);
331
332         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
333         client_info = &(bond_info->rx_hashtbl[hash_index]);
334
335         if ((client_info->assigned) &&
336             (client_info->ip_src == arp->ip_dst) &&
337             (client_info->ip_dst == arp->ip_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(bond);
345 }
346
347 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype, struct net_device *orig_dev)
348 {
349         struct bonding *bond = bond_dev->priv;
350         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
351         int res = NET_RX_DROP;
352
353         if (dev_net(bond_dev) != &init_net)
354                 goto out;
355
356         if (!(bond_dev->flags & IFF_MASTER))
357                 goto out;
358
359         if (!arp) {
360                 dprintk("Packet has no ARP data\n");
361                 goto out;
362         }
363
364         if (skb->len < sizeof(struct arp_pkt)) {
365                 dprintk("Packet is too small to be an ARP\n");
366                 goto out;
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                 dprintk("Server received an ARP Reply from client\n");
373         }
374
375         res = NET_RX_SUCCESS;
376
377 out:
378         dev_kfree_skb(skb);
379
380         return res;
381 }
382
383 /* Caller must hold bond lock for read */
384 static struct slave *rlb_next_rx_slave(struct bonding *bond)
385 {
386         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
387         struct slave *rx_slave, *slave, *start_at;
388         int i = 0;
389
390         if (bond_info->next_rx_slave) {
391                 start_at = bond_info->next_rx_slave;
392         } else {
393                 start_at = bond->first_slave;
394         }
395
396         rx_slave = NULL;
397
398         bond_for_each_slave_from(bond, slave, i, start_at) {
399                 if (SLAVE_IS_OK(slave)) {
400                         if (!rx_slave) {
401                                 rx_slave = slave;
402                         } else if (slave->speed > rx_slave->speed) {
403                                 rx_slave = slave;
404                         }
405                 }
406         }
407
408         if (rx_slave) {
409                 bond_info->next_rx_slave = rx_slave->next;
410         }
411
412         return rx_slave;
413 }
414
415 /* teach the switch the mac of a disabled slave
416  * on the primary for fault tolerance
417  *
418  * Caller must hold bond->curr_slave_lock for write or bond lock for write
419  */
420 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
421 {
422         if (!bond->curr_active_slave) {
423                 return;
424         }
425
426         if (!bond->alb_info.primary_is_promisc) {
427                 if (!dev_set_promiscuity(bond->curr_active_slave->dev, 1))
428                         bond->alb_info.primary_is_promisc = 1;
429                 else
430                         bond->alb_info.primary_is_promisc = 0;
431         }
432
433         bond->alb_info.rlb_promisc_timeout_counter = 0;
434
435         alb_send_learning_packets(bond->curr_active_slave, addr);
436 }
437
438 /* slave being removed should not be active at this point
439  *
440  * Caller must hold bond lock for read
441  */
442 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
443 {
444         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
445         struct rlb_client_info *rx_hash_table;
446         u32 index, next_index;
447
448         /* clear slave from rx_hashtbl */
449         _lock_rx_hashtbl(bond);
450
451         rx_hash_table = bond_info->rx_hashtbl;
452         index = bond_info->rx_hashtbl_head;
453         for (; index != RLB_NULL_INDEX; index = next_index) {
454                 next_index = rx_hash_table[index].next;
455                 if (rx_hash_table[index].slave == slave) {
456                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
457
458                         if (assigned_slave) {
459                                 rx_hash_table[index].slave = assigned_slave;
460                                 if (memcmp(rx_hash_table[index].mac_dst,
461                                            mac_bcast, ETH_ALEN)) {
462                                         bond_info->rx_hashtbl[index].ntt = 1;
463                                         bond_info->rx_ntt = 1;
464                                         /* A slave has been removed from the
465                                          * table because it is either disabled
466                                          * or being released. We must retry the
467                                          * update to avoid clients from not
468                                          * being updated & disconnecting when
469                                          * there is stress
470                                          */
471                                         bond_info->rlb_update_retry_counter =
472                                                 RLB_UPDATE_RETRY;
473                                 }
474                         } else {  /* there is no active slave */
475                                 rx_hash_table[index].slave = NULL;
476                         }
477                 }
478         }
479
480         _unlock_rx_hashtbl(bond);
481
482         write_lock_bh(&bond->curr_slave_lock);
483
484         if (slave != bond->curr_active_slave) {
485                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
486         }
487
488         write_unlock_bh(&bond->curr_slave_lock);
489 }
490
491 static void rlb_update_client(struct rlb_client_info *client_info)
492 {
493         int i;
494
495         if (!client_info->slave) {
496                 return;
497         }
498
499         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
500                 struct sk_buff *skb;
501
502                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
503                                  client_info->ip_dst,
504                                  client_info->slave->dev,
505                                  client_info->ip_src,
506                                  client_info->mac_dst,
507                                  client_info->slave->dev->dev_addr,
508                                  client_info->mac_dst);
509                 if (!skb) {
510                         printk(KERN_ERR DRV_NAME
511                                ": %s: Error: failed to create an ARP packet\n",
512                                client_info->slave->dev->master->name);
513                         continue;
514                 }
515
516                 skb->dev = client_info->slave->dev;
517
518                 if (client_info->tag) {
519                         skb = vlan_put_tag(skb, client_info->vlan_id);
520                         if (!skb) {
521                                 printk(KERN_ERR DRV_NAME
522                                        ": %s: Error: failed to insert VLAN tag\n",
523                                        client_info->slave->dev->master->name);
524                                 continue;
525                         }
526                 }
527
528                 arp_xmit(skb);
529         }
530 }
531
532 /* sends ARP REPLIES that update the clients that need updating */
533 static void rlb_update_rx_clients(struct bonding *bond)
534 {
535         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
536         struct rlb_client_info *client_info;
537         u32 hash_index;
538
539         _lock_rx_hashtbl(bond);
540
541         hash_index = bond_info->rx_hashtbl_head;
542         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
543                 client_info = &(bond_info->rx_hashtbl[hash_index]);
544                 if (client_info->ntt) {
545                         rlb_update_client(client_info);
546                         if (bond_info->rlb_update_retry_counter == 0) {
547                                 client_info->ntt = 0;
548                         }
549                 }
550         }
551
552         /* do not update the entries again untill this counter is zero so that
553          * not to confuse the clients.
554          */
555         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
556
557         _unlock_rx_hashtbl(bond);
558 }
559
560 /* The slave was assigned a new mac address - update the clients */
561 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
562 {
563         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
564         struct rlb_client_info *client_info;
565         int ntt = 0;
566         u32 hash_index;
567
568         _lock_rx_hashtbl(bond);
569
570         hash_index = bond_info->rx_hashtbl_head;
571         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
572                 client_info = &(bond_info->rx_hashtbl[hash_index]);
573
574                 if ((client_info->slave == slave) &&
575                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
576                         client_info->ntt = 1;
577                         ntt = 1;
578                 }
579         }
580
581         // update the team's flag only after the whole iteration
582         if (ntt) {
583                 bond_info->rx_ntt = 1;
584                 //fasten the change
585                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
586         }
587
588         _unlock_rx_hashtbl(bond);
589 }
590
591 /* mark all clients using src_ip to be updated */
592 static void rlb_req_update_subnet_clients(struct bonding *bond, __be32 src_ip)
593 {
594         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
595         struct rlb_client_info *client_info;
596         u32 hash_index;
597
598         _lock_rx_hashtbl(bond);
599
600         hash_index = bond_info->rx_hashtbl_head;
601         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
602                 client_info = &(bond_info->rx_hashtbl[hash_index]);
603
604                 if (!client_info->slave) {
605                         printk(KERN_ERR DRV_NAME
606                                ": %s: Error: found a client with no channel in "
607                                "the client's hash table\n",
608                                bond->dev->name);
609                         continue;
610                 }
611                 /*update all clients using this src_ip, that are not assigned
612                  * to the team's address (curr_active_slave) and have a known
613                  * unicast mac address.
614                  */
615                 if ((client_info->ip_src == src_ip) &&
616                     memcmp(client_info->slave->dev->dev_addr,
617                            bond->dev->dev_addr, ETH_ALEN) &&
618                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
619                         client_info->ntt = 1;
620                         bond_info->rx_ntt = 1;
621                 }
622         }
623
624         _unlock_rx_hashtbl(bond);
625 }
626
627 /* Caller must hold both bond and ptr locks for read */
628 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
629 {
630         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
631         struct arp_pkt *arp = arp_pkt(skb);
632         struct slave *assigned_slave;
633         struct rlb_client_info *client_info;
634         u32 hash_index = 0;
635
636         _lock_rx_hashtbl(bond);
637
638         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_src));
639         client_info = &(bond_info->rx_hashtbl[hash_index]);
640
641         if (client_info->assigned) {
642                 if ((client_info->ip_src == arp->ip_src) &&
643                     (client_info->ip_dst == arp->ip_dst)) {
644                         /* the entry is already assigned to this client */
645                         if (memcmp(arp->mac_dst, mac_bcast, ETH_ALEN)) {
646                                 /* update mac address from arp */
647                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
648                         }
649
650                         assigned_slave = client_info->slave;
651                         if (assigned_slave) {
652                                 _unlock_rx_hashtbl(bond);
653                                 return assigned_slave;
654                         }
655                 } else {
656                         /* the entry is already assigned to some other client,
657                          * move the old client to primary (curr_active_slave) so
658                          * that the new client can be assigned to this entry.
659                          */
660                         if (bond->curr_active_slave &&
661                             client_info->slave != bond->curr_active_slave) {
662                                 client_info->slave = bond->curr_active_slave;
663                                 rlb_update_client(client_info);
664                         }
665                 }
666         }
667         /* assign a new slave */
668         assigned_slave = rlb_next_rx_slave(bond);
669
670         if (assigned_slave) {
671                 client_info->ip_src = arp->ip_src;
672                 client_info->ip_dst = arp->ip_dst;
673                 /* arp->mac_dst is broadcast for arp reqeusts.
674                  * will be updated with clients actual unicast mac address
675                  * upon receiving an arp reply.
676                  */
677                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
678                 client_info->slave = assigned_slave;
679
680                 if (memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
681                         client_info->ntt = 1;
682                         bond->alb_info.rx_ntt = 1;
683                 } else {
684                         client_info->ntt = 0;
685                 }
686
687                 if (!list_empty(&bond->vlan_list)) {
688                         if (!vlan_get_tag(skb, &client_info->vlan_id))
689                                 client_info->tag = 1;
690                 }
691
692                 if (!client_info->assigned) {
693                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
694                         bond_info->rx_hashtbl_head = hash_index;
695                         client_info->next = prev_tbl_head;
696                         if (prev_tbl_head != RLB_NULL_INDEX) {
697                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
698                                         hash_index;
699                         }
700                         client_info->assigned = 1;
701                 }
702         }
703
704         _unlock_rx_hashtbl(bond);
705
706         return assigned_slave;
707 }
708
709 /* chooses (and returns) transmit channel for arp reply
710  * does not choose channel for other arp types since they are
711  * sent on the curr_active_slave
712  */
713 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
714 {
715         struct arp_pkt *arp = arp_pkt(skb);
716         struct slave *tx_slave = NULL;
717
718         if (arp->op_code == htons(ARPOP_REPLY)) {
719                 /* the arp must be sent on the selected
720                 * rx channel
721                 */
722                 tx_slave = rlb_choose_channel(skb, bond);
723                 if (tx_slave) {
724                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
725                 }
726                 dprintk("Server sent ARP Reply packet\n");
727         } else if (arp->op_code == htons(ARPOP_REQUEST)) {
728                 /* Create an entry in the rx_hashtbl for this client as a
729                  * place holder.
730                  * When the arp reply is received the entry will be updated
731                  * with the correct unicast address of the client.
732                  */
733                 rlb_choose_channel(skb, bond);
734
735                 /* The ARP relpy packets must be delayed so that
736                  * they can cancel out the influence of the ARP request.
737                  */
738                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
739
740                 /* arp requests are broadcast and are sent on the primary
741                  * the arp request will collapse all clients on the subnet to
742                  * the primary slave. We must register these clients to be
743                  * updated with their assigned mac.
744                  */
745                 rlb_req_update_subnet_clients(bond, arp->ip_src);
746                 dprintk("Server sent ARP Request packet\n");
747         }
748
749         return tx_slave;
750 }
751
752 /* Caller must hold bond lock for read */
753 static void rlb_rebalance(struct bonding *bond)
754 {
755         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
756         struct slave *assigned_slave;
757         struct rlb_client_info *client_info;
758         int ntt;
759         u32 hash_index;
760
761         _lock_rx_hashtbl(bond);
762
763         ntt = 0;
764         hash_index = bond_info->rx_hashtbl_head;
765         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
766                 client_info = &(bond_info->rx_hashtbl[hash_index]);
767                 assigned_slave = rlb_next_rx_slave(bond);
768                 if (assigned_slave && (client_info->slave != assigned_slave)) {
769                         client_info->slave = assigned_slave;
770                         client_info->ntt = 1;
771                         ntt = 1;
772                 }
773         }
774
775         /* update the team's flag only after the whole iteration */
776         if (ntt) {
777                 bond_info->rx_ntt = 1;
778         }
779         _unlock_rx_hashtbl(bond);
780 }
781
782 /* Caller must hold rx_hashtbl lock */
783 static void rlb_init_table_entry(struct rlb_client_info *entry)
784 {
785         memset(entry, 0, sizeof(struct rlb_client_info));
786         entry->next = RLB_NULL_INDEX;
787         entry->prev = RLB_NULL_INDEX;
788 }
789
790 static int rlb_initialize(struct bonding *bond)
791 {
792         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
793         struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
794         struct rlb_client_info  *new_hashtbl;
795         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
796         int i;
797
798         spin_lock_init(&(bond_info->rx_hashtbl_lock));
799
800         new_hashtbl = kmalloc(size, GFP_KERNEL);
801         if (!new_hashtbl) {
802                 printk(KERN_ERR DRV_NAME
803                        ": %s: Error: Failed to allocate RLB hash table\n",
804                        bond->dev->name);
805                 return -1;
806         }
807         _lock_rx_hashtbl(bond);
808
809         bond_info->rx_hashtbl = new_hashtbl;
810
811         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
812
813         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
814                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
815         }
816
817         _unlock_rx_hashtbl(bond);
818
819         /*initialize packet type*/
820         pk_type->type = __constant_htons(ETH_P_ARP);
821         pk_type->dev = bond->dev;
822         pk_type->func = rlb_arp_recv;
823
824         /* register to receive ARPs */
825         dev_add_pack(pk_type);
826
827         return 0;
828 }
829
830 static void rlb_deinitialize(struct bonding *bond)
831 {
832         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
833
834         dev_remove_pack(&(bond_info->rlb_pkt_type));
835
836         _lock_rx_hashtbl(bond);
837
838         kfree(bond_info->rx_hashtbl);
839         bond_info->rx_hashtbl = NULL;
840         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
841
842         _unlock_rx_hashtbl(bond);
843 }
844
845 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
846 {
847         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
848         u32 curr_index;
849
850         _lock_rx_hashtbl(bond);
851
852         curr_index = bond_info->rx_hashtbl_head;
853         while (curr_index != RLB_NULL_INDEX) {
854                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
855                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
856                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
857
858                 if (curr->tag && (curr->vlan_id == vlan_id)) {
859                         if (curr_index == bond_info->rx_hashtbl_head) {
860                                 bond_info->rx_hashtbl_head = next_index;
861                         }
862                         if (prev_index != RLB_NULL_INDEX) {
863                                 bond_info->rx_hashtbl[prev_index].next = next_index;
864                         }
865                         if (next_index != RLB_NULL_INDEX) {
866                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
867                         }
868
869                         rlb_init_table_entry(curr);
870                 }
871
872                 curr_index = next_index;
873         }
874
875         _unlock_rx_hashtbl(bond);
876 }
877
878 /*********************** tlb/rlb shared functions *********************/
879
880 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
881 {
882         struct bonding *bond = bond_get_bond_by_slave(slave);
883         struct learning_pkt pkt;
884         int size = sizeof(struct learning_pkt);
885         int i;
886
887         memset(&pkt, 0, size);
888         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
889         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
890         pkt.type = __constant_htons(ETH_P_LOOP);
891
892         for (i = 0; i < MAX_LP_BURST; i++) {
893                 struct sk_buff *skb;
894                 char *data;
895
896                 skb = dev_alloc_skb(size);
897                 if (!skb) {
898                         return;
899                 }
900
901                 data = skb_put(skb, size);
902                 memcpy(data, &pkt, size);
903
904                 skb_reset_mac_header(skb);
905                 skb->network_header = skb->mac_header + ETH_HLEN;
906                 skb->protocol = pkt.type;
907                 skb->priority = TC_PRIO_CONTROL;
908                 skb->dev = slave->dev;
909
910                 if (!list_empty(&bond->vlan_list)) {
911                         struct vlan_entry *vlan;
912
913                         vlan = bond_next_vlan(bond,
914                                               bond->alb_info.current_alb_vlan);
915
916                         bond->alb_info.current_alb_vlan = vlan;
917                         if (!vlan) {
918                                 kfree_skb(skb);
919                                 continue;
920                         }
921
922                         skb = vlan_put_tag(skb, vlan->vlan_id);
923                         if (!skb) {
924                                 printk(KERN_ERR DRV_NAME
925                                        ": %s: Error: failed to insert VLAN tag\n",
926                                        bond->dev->name);
927                                 continue;
928                         }
929                 }
930
931                 dev_queue_xmit(skb);
932         }
933 }
934
935 /* hw is a boolean parameter that determines whether we should try and
936  * set the hw address of the device as well as the hw address of the
937  * net_device
938  */
939 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
940 {
941         struct net_device *dev = slave->dev;
942         struct sockaddr s_addr;
943
944         if (!hw) {
945                 memcpy(dev->dev_addr, addr, dev->addr_len);
946                 return 0;
947         }
948
949         /* for rlb each slave must have a unique hw mac addresses so that */
950         /* each slave will receive packets destined to a different mac */
951         memcpy(s_addr.sa_data, addr, dev->addr_len);
952         s_addr.sa_family = dev->type;
953         if (dev_set_mac_address(dev, &s_addr)) {
954                 printk(KERN_ERR DRV_NAME
955                        ": %s: Error: dev_set_mac_address of dev %s failed! ALB "
956                        "mode requires that the base driver support setting "
957                        "the hw address also when the network device's "
958                        "interface is open\n",
959                        dev->master->name, dev->name);
960                 return -EOPNOTSUPP;
961         }
962         return 0;
963 }
964
965 /*
966  * Swap MAC addresses between two slaves.
967  *
968  * Called with RTNL held, and no other locks.
969  *
970  */
971
972 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
973 {
974         u8 tmp_mac_addr[ETH_ALEN];
975
976         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
977         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
978         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
979
980 }
981
982 /*
983  * Send learning packets after MAC address swap.
984  *
985  * Called with RTNL and no other locks
986  */
987 static void alb_fasten_mac_swap(struct bonding *bond, struct slave *slave1,
988                                 struct slave *slave2)
989 {
990         int slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
991         struct slave *disabled_slave = NULL;
992
993         ASSERT_RTNL();
994
995         /* fasten the change in the switch */
996         if (SLAVE_IS_OK(slave1)) {
997                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
998                 if (bond->alb_info.rlb_enabled) {
999                         /* inform the clients that the mac address
1000                          * has changed
1001                          */
1002                         rlb_req_update_slave_clients(bond, slave1);
1003                 }
1004         } else {
1005                 disabled_slave = slave1;
1006         }
1007
1008         if (SLAVE_IS_OK(slave2)) {
1009                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
1010                 if (bond->alb_info.rlb_enabled) {
1011                         /* inform the clients that the mac address
1012                          * has changed
1013                          */
1014                         rlb_req_update_slave_clients(bond, slave2);
1015                 }
1016         } else {
1017                 disabled_slave = slave2;
1018         }
1019
1020         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1021                 /* A disabled slave was assigned an active mac addr */
1022                 rlb_teach_disabled_mac_on_primary(bond,
1023                                                   disabled_slave->dev->dev_addr);
1024         }
1025 }
1026
1027 /**
1028  * alb_change_hw_addr_on_detach
1029  * @bond: bonding we're working on
1030  * @slave: the slave that was just detached
1031  *
1032  * We assume that @slave was already detached from the slave list.
1033  *
1034  * If @slave's permanent hw address is different both from its current
1035  * address and from @bond's address, then somewhere in the bond there's
1036  * a slave that has @slave's permanet address as its current address.
1037  * We'll make sure that that slave no longer uses @slave's permanent address.
1038  *
1039  * Caller must hold RTNL and no other locks
1040  */
1041 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1042 {
1043         int perm_curr_diff;
1044         int perm_bond_diff;
1045
1046         perm_curr_diff = memcmp(slave->perm_hwaddr,
1047                                 slave->dev->dev_addr,
1048                                 ETH_ALEN);
1049         perm_bond_diff = memcmp(slave->perm_hwaddr,
1050                                 bond->dev->dev_addr,
1051                                 ETH_ALEN);
1052
1053         if (perm_curr_diff && perm_bond_diff) {
1054                 struct slave *tmp_slave;
1055                 int i, found = 0;
1056
1057                 bond_for_each_slave(bond, tmp_slave, i) {
1058                         if (!memcmp(slave->perm_hwaddr,
1059                                     tmp_slave->dev->dev_addr,
1060                                     ETH_ALEN)) {
1061                                 found = 1;
1062                                 break;
1063                         }
1064                 }
1065
1066                 if (found) {
1067                         /* locking: needs RTNL and nothing else */
1068                         alb_swap_mac_addr(bond, slave, tmp_slave);
1069                         alb_fasten_mac_swap(bond, slave, tmp_slave);
1070                 }
1071         }
1072 }
1073
1074 /**
1075  * alb_handle_addr_collision_on_attach
1076  * @bond: bonding we're working on
1077  * @slave: the slave that was just attached
1078  *
1079  * checks uniqueness of slave's mac address and handles the case the
1080  * new slave uses the bonds mac address.
1081  *
1082  * If the permanent hw address of @slave is @bond's hw address, we need to
1083  * find a different hw address to give @slave, that isn't in use by any other
1084  * slave in the bond. This address must be, of course, one of the premanent
1085  * addresses of the other slaves.
1086  *
1087  * We go over the slave list, and for each slave there we compare its
1088  * permanent hw address with the current address of all the other slaves.
1089  * If no match was found, then we've found a slave with a permanent address
1090  * that isn't used by any other slave in the bond, so we can assign it to
1091  * @slave.
1092  *
1093  * assumption: this function is called before @slave is attached to the
1094  *             bond slave list.
1095  *
1096  * caller must hold the bond lock for write since the mac addresses are compared
1097  * and may be swapped.
1098  */
1099 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1100 {
1101         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1102         struct slave *has_bond_addr = bond->curr_active_slave;
1103         int i, j, found = 0;
1104
1105         if (bond->slave_cnt == 0) {
1106                 /* this is the first slave */
1107                 return 0;
1108         }
1109
1110         /* if slave's mac address differs from bond's mac address
1111          * check uniqueness of slave's mac address against the other
1112          * slaves in the bond.
1113          */
1114         if (memcmp(slave->perm_hwaddr, bond->dev->dev_addr, ETH_ALEN)) {
1115                 bond_for_each_slave(bond, tmp_slave1, i) {
1116                         if (!memcmp(tmp_slave1->dev->dev_addr, slave->dev->dev_addr,
1117                                     ETH_ALEN)) {
1118                                 found = 1;
1119                                 break;
1120                         }
1121                 }
1122
1123                 if (!found)
1124                         return 0;
1125
1126                 /* Try setting slave mac to bond address and fall-through
1127                    to code handling that situation below... */
1128                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1129                                        bond->alb_info.rlb_enabled);
1130         }
1131
1132         /* The slave's address is equal to the address of the bond.
1133          * Search for a spare address in the bond for this slave.
1134          */
1135         free_mac_slave = NULL;
1136
1137         bond_for_each_slave(bond, tmp_slave1, i) {
1138                 found = 0;
1139                 bond_for_each_slave(bond, tmp_slave2, j) {
1140                         if (!memcmp(tmp_slave1->perm_hwaddr,
1141                                     tmp_slave2->dev->dev_addr,
1142                                     ETH_ALEN)) {
1143                                 found = 1;
1144                                 break;
1145                         }
1146                 }
1147
1148                 if (!found) {
1149                         /* no slave has tmp_slave1's perm addr
1150                          * as its curr addr
1151                          */
1152                         free_mac_slave = tmp_slave1;
1153                         break;
1154                 }
1155
1156                 if (!has_bond_addr) {
1157                         if (!memcmp(tmp_slave1->dev->dev_addr,
1158                                     bond->dev->dev_addr,
1159                                     ETH_ALEN)) {
1160
1161                                 has_bond_addr = tmp_slave1;
1162                         }
1163                 }
1164         }
1165
1166         if (free_mac_slave) {
1167                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1168                                        bond->alb_info.rlb_enabled);
1169
1170                 printk(KERN_WARNING DRV_NAME
1171                        ": %s: Warning: the hw address of slave %s is in use by "
1172                        "the bond; giving it the hw address of %s\n",
1173                        bond->dev->name, slave->dev->name, free_mac_slave->dev->name);
1174
1175         } else if (has_bond_addr) {
1176                 printk(KERN_ERR DRV_NAME
1177                        ": %s: Error: the hw address of slave %s is in use by the "
1178                        "bond; couldn't find a slave with a free hw address to "
1179                        "give it (this should not have happened)\n",
1180                        bond->dev->name, slave->dev->name);
1181                 return -EFAULT;
1182         }
1183
1184         return 0;
1185 }
1186
1187 /**
1188  * alb_set_mac_address
1189  * @bond:
1190  * @addr:
1191  *
1192  * In TLB mode all slaves are configured to the bond's hw address, but set
1193  * their dev_addr field to different addresses (based on their permanent hw
1194  * addresses).
1195  *
1196  * For each slave, this function sets the interface to the new address and then
1197  * changes its dev_addr field to its previous value.
1198  *
1199  * Unwinding assumes bond's mac address has not yet changed.
1200  */
1201 static int alb_set_mac_address(struct bonding *bond, void *addr)
1202 {
1203         struct sockaddr sa;
1204         struct slave *slave, *stop_at;
1205         char tmp_addr[ETH_ALEN];
1206         int res;
1207         int i;
1208
1209         if (bond->alb_info.rlb_enabled) {
1210                 return 0;
1211         }
1212
1213         bond_for_each_slave(bond, slave, i) {
1214                 if (slave->dev->set_mac_address == NULL) {
1215                         res = -EOPNOTSUPP;
1216                         goto unwind;
1217                 }
1218
1219                 /* save net_device's current hw address */
1220                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1221
1222                 res = dev_set_mac_address(slave->dev, addr);
1223
1224                 /* restore net_device's hw address */
1225                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1226
1227                 if (res) {
1228                         goto unwind;
1229                 }
1230         }
1231
1232         return 0;
1233
1234 unwind:
1235         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1236         sa.sa_family = bond->dev->type;
1237
1238         /* unwind from head to the slave that failed */
1239         stop_at = slave;
1240         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1241                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1242                 dev_set_mac_address(slave->dev, &sa);
1243                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1244         }
1245
1246         return res;
1247 }
1248
1249 /************************ exported alb funcions ************************/
1250
1251 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1252 {
1253         int res;
1254
1255         res = tlb_initialize(bond);
1256         if (res) {
1257                 return res;
1258         }
1259
1260         if (rlb_enabled) {
1261                 bond->alb_info.rlb_enabled = 1;
1262                 /* initialize rlb */
1263                 res = rlb_initialize(bond);
1264                 if (res) {
1265                         tlb_deinitialize(bond);
1266                         return res;
1267                 }
1268         } else {
1269                 bond->alb_info.rlb_enabled = 0;
1270         }
1271
1272         return 0;
1273 }
1274
1275 void bond_alb_deinitialize(struct bonding *bond)
1276 {
1277         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1278
1279         tlb_deinitialize(bond);
1280
1281         if (bond_info->rlb_enabled) {
1282                 rlb_deinitialize(bond);
1283         }
1284 }
1285
1286 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1287 {
1288         struct bonding *bond = bond_dev->priv;
1289         struct ethhdr *eth_data;
1290         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1291         struct slave *tx_slave = NULL;
1292         static const __be32 ip_bcast = htonl(0xffffffff);
1293         int hash_size = 0;
1294         int do_tx_balance = 1;
1295         u32 hash_index = 0;
1296         const u8 *hash_start = NULL;
1297         int res = 1;
1298         struct ipv6hdr *ip6hdr;
1299
1300         skb_reset_mac_header(skb);
1301         eth_data = eth_hdr(skb);
1302
1303         /* make sure that the curr_active_slave and the slaves list do
1304          * not change during tx
1305          */
1306         read_lock(&bond->lock);
1307         read_lock(&bond->curr_slave_lock);
1308
1309         if (!BOND_IS_OK(bond)) {
1310                 goto out;
1311         }
1312
1313         switch (ntohs(skb->protocol)) {
1314         case ETH_P_IP: {
1315                 const struct iphdr *iph = ip_hdr(skb);
1316
1317                 if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
1318                     (iph->daddr == ip_bcast) ||
1319                     (iph->protocol == IPPROTO_IGMP)) {
1320                         do_tx_balance = 0;
1321                         break;
1322                 }
1323                 hash_start = (char *)&(iph->daddr);
1324                 hash_size = sizeof(iph->daddr);
1325         }
1326                 break;
1327         case ETH_P_IPV6:
1328                 /* IPv6 doesn't really use broadcast mac address, but leave
1329                  * that here just in case.
1330                  */
1331                 if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
1332                         do_tx_balance = 0;
1333                         break;
1334                 }
1335
1336                 /* IPv6 uses all-nodes multicast as an equivalent to
1337                  * broadcasts in IPv4.
1338                  */
1339                 if (memcmp(eth_data->h_dest, mac_v6_allmcast, ETH_ALEN) == 0) {
1340                         do_tx_balance = 0;
1341                         break;
1342                 }
1343
1344                 /* Additianally, DAD probes should not be tx-balanced as that
1345                  * will lead to false positives for duplicate addresses and
1346                  * prevent address configuration from working.
1347                  */
1348                 ip6hdr = ipv6_hdr(skb);
1349                 if (ipv6_addr_any(&ip6hdr->saddr)) {
1350                         do_tx_balance = 0;
1351                         break;
1352                 }
1353
1354                 hash_start = (char *)&(ipv6_hdr(skb)->daddr);
1355                 hash_size = sizeof(ipv6_hdr(skb)->daddr);
1356                 break;
1357         case ETH_P_IPX:
1358                 if (ipx_hdr(skb)->ipx_checksum != IPX_NO_CHECKSUM) {
1359                         /* something is wrong with this packet */
1360                         do_tx_balance = 0;
1361                         break;
1362                 }
1363
1364                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1365                         /* The only protocol worth balancing in
1366                          * this family since it has an "ARP" like
1367                          * mechanism
1368                          */
1369                         do_tx_balance = 0;
1370                         break;
1371                 }
1372
1373                 hash_start = (char*)eth_data->h_dest;
1374                 hash_size = ETH_ALEN;
1375                 break;
1376         case ETH_P_ARP:
1377                 do_tx_balance = 0;
1378                 if (bond_info->rlb_enabled) {
1379                         tx_slave = rlb_arp_xmit(skb, bond);
1380                 }
1381                 break;
1382         default:
1383                 do_tx_balance = 0;
1384                 break;
1385         }
1386
1387         if (do_tx_balance) {
1388                 hash_index = _simple_hash(hash_start, hash_size);
1389                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1390         }
1391
1392         if (!tx_slave) {
1393                 /* unbalanced or unassigned, send through primary */
1394                 tx_slave = bond->curr_active_slave;
1395                 bond_info->unbalanced_load += skb->len;
1396         }
1397
1398         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1399                 if (tx_slave != bond->curr_active_slave) {
1400                         memcpy(eth_data->h_source,
1401                                tx_slave->dev->dev_addr,
1402                                ETH_ALEN);
1403                 }
1404
1405                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1406         } else {
1407                 if (tx_slave) {
1408                         tlb_clear_slave(bond, tx_slave, 0);
1409                 }
1410         }
1411
1412 out:
1413         if (res) {
1414                 /* no suitable interface, frame not sent */
1415                 dev_kfree_skb(skb);
1416         }
1417         read_unlock(&bond->curr_slave_lock);
1418         read_unlock(&bond->lock);
1419         return 0;
1420 }
1421
1422 void bond_alb_monitor(struct work_struct *work)
1423 {
1424         struct bonding *bond = container_of(work, struct bonding,
1425                                             alb_work.work);
1426         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1427         struct slave *slave;
1428         int i;
1429
1430         read_lock(&bond->lock);
1431
1432         if (bond->kill_timers) {
1433                 goto out;
1434         }
1435
1436         if (bond->slave_cnt == 0) {
1437                 bond_info->tx_rebalance_counter = 0;
1438                 bond_info->lp_counter = 0;
1439                 goto re_arm;
1440         }
1441
1442         bond_info->tx_rebalance_counter++;
1443         bond_info->lp_counter++;
1444
1445         /* send learning packets */
1446         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1447                 /* change of curr_active_slave involves swapping of mac addresses.
1448                  * in order to avoid this swapping from happening while
1449                  * sending the learning packets, the curr_slave_lock must be held for
1450                  * read.
1451                  */
1452                 read_lock(&bond->curr_slave_lock);
1453
1454                 bond_for_each_slave(bond, slave, i) {
1455                         alb_send_learning_packets(slave, slave->dev->dev_addr);
1456                 }
1457
1458                 read_unlock(&bond->curr_slave_lock);
1459
1460                 bond_info->lp_counter = 0;
1461         }
1462
1463         /* rebalance tx traffic */
1464         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1465
1466                 read_lock(&bond->curr_slave_lock);
1467
1468                 bond_for_each_slave(bond, slave, i) {
1469                         tlb_clear_slave(bond, slave, 1);
1470                         if (slave == bond->curr_active_slave) {
1471                                 SLAVE_TLB_INFO(slave).load =
1472                                         bond_info->unbalanced_load /
1473                                                 BOND_TLB_REBALANCE_INTERVAL;
1474                                 bond_info->unbalanced_load = 0;
1475                         }
1476                 }
1477
1478                 read_unlock(&bond->curr_slave_lock);
1479
1480                 bond_info->tx_rebalance_counter = 0;
1481         }
1482
1483         /* handle rlb stuff */
1484         if (bond_info->rlb_enabled) {
1485                 if (bond_info->primary_is_promisc &&
1486                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1487
1488                         /*
1489                          * dev_set_promiscuity requires rtnl and
1490                          * nothing else.
1491                          */
1492                         read_unlock(&bond->lock);
1493                         rtnl_lock();
1494
1495                         bond_info->rlb_promisc_timeout_counter = 0;
1496
1497                         /* If the primary was set to promiscuous mode
1498                          * because a slave was disabled then
1499                          * it can now leave promiscuous mode.
1500                          */
1501                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1502                         bond_info->primary_is_promisc = 0;
1503
1504                         rtnl_unlock();
1505                         read_lock(&bond->lock);
1506                 }
1507
1508                 if (bond_info->rlb_rebalance) {
1509                         bond_info->rlb_rebalance = 0;
1510                         rlb_rebalance(bond);
1511                 }
1512
1513                 /* check if clients need updating */
1514                 if (bond_info->rx_ntt) {
1515                         if (bond_info->rlb_update_delay_counter) {
1516                                 --bond_info->rlb_update_delay_counter;
1517                         } else {
1518                                 rlb_update_rx_clients(bond);
1519                                 if (bond_info->rlb_update_retry_counter) {
1520                                         --bond_info->rlb_update_retry_counter;
1521                                 } else {
1522                                         bond_info->rx_ntt = 0;
1523                                 }
1524                         }
1525                 }
1526         }
1527
1528 re_arm:
1529         queue_delayed_work(bond->wq, &bond->alb_work, alb_delta_in_ticks);
1530 out:
1531         read_unlock(&bond->lock);
1532 }
1533
1534 /* assumption: called before the slave is attached to the bond
1535  * and not locked by the bond lock
1536  */
1537 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1538 {
1539         int res;
1540
1541         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1542                                      bond->alb_info.rlb_enabled);
1543         if (res) {
1544                 return res;
1545         }
1546
1547         /* caller must hold the bond lock for write since the mac addresses
1548          * are compared and may be swapped.
1549          */
1550         read_lock(&bond->lock);
1551
1552         res = alb_handle_addr_collision_on_attach(bond, slave);
1553
1554         read_unlock(&bond->lock);
1555
1556         if (res) {
1557                 return res;
1558         }
1559
1560         tlb_init_slave(slave);
1561
1562         /* order a rebalance ASAP */
1563         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1564
1565         if (bond->alb_info.rlb_enabled) {
1566                 bond->alb_info.rlb_rebalance = 1;
1567         }
1568
1569         return 0;
1570 }
1571
1572 /*
1573  * Remove slave from tlb and rlb hash tables, and fix up MAC addresses
1574  * if necessary.
1575  *
1576  * Caller must hold RTNL and no other locks
1577  */
1578 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1579 {
1580         if (bond->slave_cnt > 1) {
1581                 alb_change_hw_addr_on_detach(bond, slave);
1582         }
1583
1584         tlb_clear_slave(bond, slave, 0);
1585
1586         if (bond->alb_info.rlb_enabled) {
1587                 bond->alb_info.next_rx_slave = NULL;
1588                 rlb_clear_slave(bond, slave);
1589         }
1590 }
1591
1592 /* Caller must hold bond lock for read */
1593 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1594 {
1595         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1596
1597         if (link == BOND_LINK_DOWN) {
1598                 tlb_clear_slave(bond, slave, 0);
1599                 if (bond->alb_info.rlb_enabled) {
1600                         rlb_clear_slave(bond, slave);
1601                 }
1602         } else if (link == BOND_LINK_UP) {
1603                 /* order a rebalance ASAP */
1604                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1605                 if (bond->alb_info.rlb_enabled) {
1606                         bond->alb_info.rlb_rebalance = 1;
1607                         /* If the updelay module parameter is smaller than the
1608                          * forwarding delay of the switch the rebalance will
1609                          * not work because the rebalance arp replies will
1610                          * not be forwarded to the clients..
1611                          */
1612                 }
1613         }
1614 }
1615
1616 /**
1617  * bond_alb_handle_active_change - assign new curr_active_slave
1618  * @bond: our bonding struct
1619  * @new_slave: new slave to assign
1620  *
1621  * Set the bond->curr_active_slave to @new_slave and handle
1622  * mac address swapping and promiscuity changes as needed.
1623  *
1624  * If new_slave is NULL, caller must hold curr_slave_lock or
1625  * bond->lock for write.
1626  *
1627  * If new_slave is not NULL, caller must hold RTNL, bond->lock for
1628  * read and curr_slave_lock for write.  Processing here may sleep, so
1629  * no other locks may be held.
1630  */
1631 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1632 {
1633         struct slave *swap_slave;
1634         int i;
1635
1636         if (bond->curr_active_slave == new_slave) {
1637                 return;
1638         }
1639
1640         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1641                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1642                 bond->alb_info.primary_is_promisc = 0;
1643                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1644         }
1645
1646         swap_slave = bond->curr_active_slave;
1647         bond->curr_active_slave = new_slave;
1648
1649         if (!new_slave || (bond->slave_cnt == 0)) {
1650                 return;
1651         }
1652
1653         /* set the new curr_active_slave to the bonds mac address
1654          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1655          */
1656         if (!swap_slave) {
1657                 struct slave *tmp_slave;
1658                 /* find slave that is holding the bond's mac address */
1659                 bond_for_each_slave(bond, tmp_slave, i) {
1660                         if (!memcmp(tmp_slave->dev->dev_addr,
1661                                     bond->dev->dev_addr, ETH_ALEN)) {
1662                                 swap_slave = tmp_slave;
1663                                 break;
1664                         }
1665                 }
1666         }
1667
1668         /*
1669          * Arrange for swap_slave and new_slave to temporarily be
1670          * ignored so we can mess with their MAC addresses without
1671          * fear of interference from transmit activity.
1672          */
1673         if (swap_slave) {
1674                 tlb_clear_slave(bond, swap_slave, 1);
1675         }
1676         tlb_clear_slave(bond, new_slave, 1);
1677
1678         write_unlock_bh(&bond->curr_slave_lock);
1679         read_unlock(&bond->lock);
1680
1681         ASSERT_RTNL();
1682
1683         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1684         if (swap_slave) {
1685                 /* swap mac address */
1686                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1687         } else {
1688                 /* set the new_slave to the bond mac address */
1689                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1690                                        bond->alb_info.rlb_enabled);
1691         }
1692
1693         if (swap_slave) {
1694                 alb_fasten_mac_swap(bond, swap_slave, new_slave);
1695                 read_lock(&bond->lock);
1696         } else {
1697                 read_lock(&bond->lock);
1698                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1699         }
1700
1701         write_lock_bh(&bond->curr_slave_lock);
1702 }
1703
1704 /*
1705  * Called with RTNL
1706  */
1707 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1708 {
1709         struct bonding *bond = bond_dev->priv;
1710         struct sockaddr *sa = addr;
1711         struct slave *slave, *swap_slave;
1712         int res;
1713         int i;
1714
1715         if (!is_valid_ether_addr(sa->sa_data)) {
1716                 return -EADDRNOTAVAIL;
1717         }
1718
1719         res = alb_set_mac_address(bond, addr);
1720         if (res) {
1721                 return res;
1722         }
1723
1724         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1725
1726         /* If there is no curr_active_slave there is nothing else to do.
1727          * Otherwise we'll need to pass the new address to it and handle
1728          * duplications.
1729          */
1730         if (!bond->curr_active_slave) {
1731                 return 0;
1732         }
1733
1734         swap_slave = NULL;
1735
1736         bond_for_each_slave(bond, slave, i) {
1737                 if (!memcmp(slave->dev->dev_addr, bond_dev->dev_addr, ETH_ALEN)) {
1738                         swap_slave = slave;
1739                         break;
1740                 }
1741         }
1742
1743         write_unlock_bh(&bond->curr_slave_lock);
1744         read_unlock(&bond->lock);
1745
1746         if (swap_slave) {
1747                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1748                 alb_fasten_mac_swap(bond, swap_slave, bond->curr_active_slave);
1749         } else {
1750                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1751                                        bond->alb_info.rlb_enabled);
1752
1753                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1754                 if (bond->alb_info.rlb_enabled) {
1755                         /* inform clients mac address has changed */
1756                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1757                 }
1758         }
1759
1760         read_lock(&bond->lock);
1761         write_lock_bh(&bond->curr_slave_lock);
1762
1763         return 0;
1764 }
1765
1766 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1767 {
1768         if (bond->alb_info.current_alb_vlan &&
1769             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1770                 bond->alb_info.current_alb_vlan = NULL;
1771         }
1772
1773         if (bond->alb_info.rlb_enabled) {
1774                 rlb_clear_vlan(bond, vlan_id);
1775         }
1776 }
1777