[PATCH] bonding: move kmalloc out of spinlock in ALB init
[linux-2.6.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  * Changes:
23  *
24  * 2003/06/25 - Shmulik Hen <shmulik.hen at intel dot com>
25  *      - Fixed signed/unsigned calculation errors that caused load sharing
26  *        to collapse to one slave under very heavy UDP Tx stress.
27  *
28  * 2003/08/06 - Amir Noam <amir.noam at intel dot com>
29  *      - Add support for setting bond's MAC address with special
30  *        handling required for ALB/TLB.
31  *
32  * 2003/12/01 - Shmulik Hen <shmulik.hen at intel dot com>
33  *      - Code cleanup and style changes
34  *
35  * 2003/12/30 - Amir Noam <amir.noam at intel dot com>
36  *      - Fixed: Cannot remove and re-enslave the original active slave.
37  *
38  * 2004/01/14 - Shmulik Hen <shmulik.hen at intel dot com>
39  *      - Add capability to tag self generated packets in ALB/TLB modes.
40  */
41
42 //#define BONDING_DEBUG 1
43
44 #include <linux/skbuff.h>
45 #include <linux/netdevice.h>
46 #include <linux/etherdevice.h>
47 #include <linux/pkt_sched.h>
48 #include <linux/spinlock.h>
49 #include <linux/slab.h>
50 #include <linux/timer.h>
51 #include <linux/ip.h>
52 #include <linux/ipv6.h>
53 #include <linux/if_arp.h>
54 #include <linux/if_ether.h>
55 #include <linux/if_bonding.h>
56 #include <linux/if_vlan.h>
57 #include <linux/in.h>
58 #include <net/ipx.h>
59 #include <net/arp.h>
60 #include <asm/byteorder.h>
61 #include "bonding.h"
62 #include "bond_alb.h"
63
64
65 #define ALB_TIMER_TICKS_PER_SEC     10  /* should be a divisor of HZ */
66 #define BOND_TLB_REBALANCE_INTERVAL 10  /* In seconds, periodic re-balancing.
67                                          * Used for division - never set
68                                          * to zero !!!
69                                          */
70 #define BOND_ALB_LP_INTERVAL        1   /* In seconds, periodic send of
71                                          * learning packets to the switch
72                                          */
73
74 #define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
75                                   * ALB_TIMER_TICKS_PER_SEC)
76
77 #define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
78                            * ALB_TIMER_TICKS_PER_SEC)
79
80 #define TLB_HASH_TABLE_SIZE 256 /* The size of the clients hash table.
81                                  * Note that this value MUST NOT be smaller
82                                  * because the key hash table is BYTE wide !
83                                  */
84
85
86 #define TLB_NULL_INDEX          0xffffffff
87 #define MAX_LP_BURST            3
88
89 /* rlb defs */
90 #define RLB_HASH_TABLE_SIZE     256
91 #define RLB_NULL_INDEX          0xffffffff
92 #define RLB_UPDATE_DELAY        2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
93 #define RLB_ARP_BURST_SIZE      2
94 #define RLB_UPDATE_RETRY        3       /* 3-ticks - must be smaller than the rlb
95                                          * rebalance interval (5 min).
96                                          */
97 /* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
98  * promiscuous after failover
99  */
100 #define RLB_PROMISC_TIMEOUT     10*ALB_TIMER_TICKS_PER_SEC
101
102 static const u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
103 static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC;
104
105 #pragma pack(1)
106 struct learning_pkt {
107         u8 mac_dst[ETH_ALEN];
108         u8 mac_src[ETH_ALEN];
109         u16 type;
110         u8 padding[ETH_ZLEN - ETH_HLEN];
111 };
112
113 struct arp_pkt {
114         u16     hw_addr_space;
115         u16     prot_addr_space;
116         u8      hw_addr_len;
117         u8      prot_addr_len;
118         u16     op_code;
119         u8      mac_src[ETH_ALEN];      /* sender hardware address */
120         u32     ip_src;                 /* sender IP address */
121         u8      mac_dst[ETH_ALEN];      /* target hardware address */
122         u32     ip_dst;                 /* target IP address */
123 };
124 #pragma pack()
125
126 /* Forward declaration */
127 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
128
129 static inline u8 _simple_hash(u8 *hash_start, int hash_size)
130 {
131         int i;
132         u8 hash = 0;
133
134         for (i = 0; i < hash_size; i++) {
135                 hash ^= hash_start[i];
136         }
137
138         return hash;
139 }
140
141 /*********************** tlb specific functions ***************************/
142
143 static inline void _lock_tx_hashtbl(struct bonding *bond)
144 {
145         spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
146 }
147
148 static inline void _unlock_tx_hashtbl(struct bonding *bond)
149 {
150         spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
151 }
152
153 /* Caller must hold tx_hashtbl lock */
154 static inline void tlb_init_table_entry(struct tlb_client_info *entry, int save_load)
155 {
156         if (save_load) {
157                 entry->load_history = 1 + entry->tx_bytes /
158                                       BOND_TLB_REBALANCE_INTERVAL;
159                 entry->tx_bytes = 0;
160         }
161
162         entry->tx_slave = NULL;
163         entry->next = TLB_NULL_INDEX;
164         entry->prev = TLB_NULL_INDEX;
165 }
166
167 static inline void tlb_init_slave(struct slave *slave)
168 {
169         SLAVE_TLB_INFO(slave).load = 0;
170         SLAVE_TLB_INFO(slave).head = TLB_NULL_INDEX;
171 }
172
173 /* Caller must hold bond lock for read */
174 static void tlb_clear_slave(struct bonding *bond, struct slave *slave, int save_load)
175 {
176         struct tlb_client_info *tx_hash_table;
177         u32 index;
178
179         _lock_tx_hashtbl(bond);
180
181         /* clear slave from tx_hashtbl */
182         tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
183
184         index = SLAVE_TLB_INFO(slave).head;
185         while (index != TLB_NULL_INDEX) {
186                 u32 next_index = tx_hash_table[index].next;
187                 tlb_init_table_entry(&tx_hash_table[index], save_load);
188                 index = next_index;
189         }
190
191         _unlock_tx_hashtbl(bond);
192
193         tlb_init_slave(slave);
194 }
195
196 /* Must be called before starting the monitor timer */
197 static int tlb_initialize(struct bonding *bond)
198 {
199         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
200         int size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
201         struct tlb_client_info *new_hashtbl;
202         int i;
203
204         spin_lock_init(&(bond_info->tx_hashtbl_lock));
205
206         new_hashtbl = kmalloc(size, GFP_KERNEL);
207         if (!new_hashtbl) {
208                 printk(KERN_ERR DRV_NAME
209                        ": %s: Error: Failed to allocate TLB hash table\n",
210                        bond->dev->name);
211                 return -1;
212         }
213         _lock_tx_hashtbl(bond);
214
215         bond_info->tx_hashtbl = new_hashtbl;
216
217         memset(bond_info->tx_hashtbl, 0, size);
218
219         for (i = 0; i < TLB_HASH_TABLE_SIZE; i++) {
220                 tlb_init_table_entry(&bond_info->tx_hashtbl[i], 1);
221         }
222
223         _unlock_tx_hashtbl(bond);
224
225         return 0;
226 }
227
228 /* Must be called only after all slaves have been released */
229 static void tlb_deinitialize(struct bonding *bond)
230 {
231         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
232
233         _lock_tx_hashtbl(bond);
234
235         kfree(bond_info->tx_hashtbl);
236         bond_info->tx_hashtbl = NULL;
237
238         _unlock_tx_hashtbl(bond);
239 }
240
241 /* Caller must hold bond lock for read */
242 static struct slave *tlb_get_least_loaded_slave(struct bonding *bond)
243 {
244         struct slave *slave, *least_loaded;
245         s64 max_gap;
246         int i, found = 0;
247
248         /* Find the first enabled slave */
249         bond_for_each_slave(bond, slave, i) {
250                 if (SLAVE_IS_OK(slave)) {
251                         found = 1;
252                         break;
253                 }
254         }
255
256         if (!found) {
257                 return NULL;
258         }
259
260         least_loaded = slave;
261         max_gap = (s64)(slave->speed << 20) - /* Convert to Megabit per sec */
262                         (s64)(SLAVE_TLB_INFO(slave).load << 3); /* Bytes to bits */
263
264         /* Find the slave with the largest gap */
265         bond_for_each_slave_from(bond, slave, i, least_loaded) {
266                 if (SLAVE_IS_OK(slave)) {
267                         s64 gap = (s64)(slave->speed << 20) -
268                                         (s64)(SLAVE_TLB_INFO(slave).load << 3);
269                         if (max_gap < gap) {
270                                 least_loaded = slave;
271                                 max_gap = gap;
272                         }
273                 }
274         }
275
276         return least_loaded;
277 }
278
279 /* Caller must hold bond lock for read */
280 static struct slave *tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
281 {
282         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
283         struct tlb_client_info *hash_table;
284         struct slave *assigned_slave;
285
286         _lock_tx_hashtbl(bond);
287
288         hash_table = bond_info->tx_hashtbl;
289         assigned_slave = hash_table[hash_index].tx_slave;
290         if (!assigned_slave) {
291                 assigned_slave = tlb_get_least_loaded_slave(bond);
292
293                 if (assigned_slave) {
294                         struct tlb_slave_info *slave_info =
295                                 &(SLAVE_TLB_INFO(assigned_slave));
296                         u32 next_index = slave_info->head;
297
298                         hash_table[hash_index].tx_slave = assigned_slave;
299                         hash_table[hash_index].next = next_index;
300                         hash_table[hash_index].prev = TLB_NULL_INDEX;
301
302                         if (next_index != TLB_NULL_INDEX) {
303                                 hash_table[next_index].prev = hash_index;
304                         }
305
306                         slave_info->head = hash_index;
307                         slave_info->load +=
308                                 hash_table[hash_index].load_history;
309                 }
310         }
311
312         if (assigned_slave) {
313                 hash_table[hash_index].tx_bytes += skb_len;
314         }
315
316         _unlock_tx_hashtbl(bond);
317
318         return assigned_slave;
319 }
320
321 /*********************** rlb specific functions ***************************/
322 static inline void _lock_rx_hashtbl(struct bonding *bond)
323 {
324         spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
325 }
326
327 static inline void _unlock_rx_hashtbl(struct bonding *bond)
328 {
329         spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
330 }
331
332 /* when an ARP REPLY is received from a client update its info
333  * in the rx_hashtbl
334  */
335 static void rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
336 {
337         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
338         struct rlb_client_info *client_info;
339         u32 hash_index;
340
341         _lock_rx_hashtbl(bond);
342
343         hash_index = _simple_hash((u8*)&(arp->ip_src), sizeof(arp->ip_src));
344         client_info = &(bond_info->rx_hashtbl[hash_index]);
345
346         if ((client_info->assigned) &&
347             (client_info->ip_src == arp->ip_dst) &&
348             (client_info->ip_dst == arp->ip_src)) {
349                 /* update the clients MAC address */
350                 memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
351                 client_info->ntt = 1;
352                 bond_info->rx_ntt = 1;
353         }
354
355         _unlock_rx_hashtbl(bond);
356 }
357
358 static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct packet_type *ptype, struct net_device *orig_dev)
359 {
360         struct bonding *bond = bond_dev->priv;
361         struct arp_pkt *arp = (struct arp_pkt *)skb->data;
362         int res = NET_RX_DROP;
363
364         if (!(bond_dev->flags & IFF_MASTER))
365                 goto out;
366
367         if (!arp) {
368                 dprintk("Packet has no ARP data\n");
369                 goto out;
370         }
371
372         if (skb->len < sizeof(struct arp_pkt)) {
373                 dprintk("Packet is too small to be an ARP\n");
374                 goto out;
375         }
376
377         if (arp->op_code == htons(ARPOP_REPLY)) {
378                 /* update rx hash table for this ARP */
379                 rlb_update_entry_from_arp(bond, arp);
380                 dprintk("Server received an ARP Reply from client\n");
381         }
382
383         res = NET_RX_SUCCESS;
384
385 out:
386         dev_kfree_skb(skb);
387
388         return res;
389 }
390
391 /* Caller must hold bond lock for read */
392 static struct slave *rlb_next_rx_slave(struct bonding *bond)
393 {
394         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
395         struct slave *rx_slave, *slave, *start_at;
396         int i = 0;
397
398         if (bond_info->next_rx_slave) {
399                 start_at = bond_info->next_rx_slave;
400         } else {
401                 start_at = bond->first_slave;
402         }
403
404         rx_slave = NULL;
405
406         bond_for_each_slave_from(bond, slave, i, start_at) {
407                 if (SLAVE_IS_OK(slave)) {
408                         if (!rx_slave) {
409                                 rx_slave = slave;
410                         } else if (slave->speed > rx_slave->speed) {
411                                 rx_slave = slave;
412                         }
413                 }
414         }
415
416         if (rx_slave) {
417                 bond_info->next_rx_slave = rx_slave->next;
418         }
419
420         return rx_slave;
421 }
422
423 /* teach the switch the mac of a disabled slave
424  * on the primary for fault tolerance
425  *
426  * Caller must hold bond->curr_slave_lock for write or bond lock for write
427  */
428 static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
429 {
430         if (!bond->curr_active_slave) {
431                 return;
432         }
433
434         if (!bond->alb_info.primary_is_promisc) {
435                 bond->alb_info.primary_is_promisc = 1;
436                 dev_set_promiscuity(bond->curr_active_slave->dev, 1);
437         }
438
439         bond->alb_info.rlb_promisc_timeout_counter = 0;
440
441         alb_send_learning_packets(bond->curr_active_slave, addr);
442 }
443
444 /* slave being removed should not be active at this point
445  *
446  * Caller must hold bond lock for read
447  */
448 static void rlb_clear_slave(struct bonding *bond, struct slave *slave)
449 {
450         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
451         struct rlb_client_info *rx_hash_table;
452         u32 index, next_index;
453
454         /* clear slave from rx_hashtbl */
455         _lock_rx_hashtbl(bond);
456
457         rx_hash_table = bond_info->rx_hashtbl;
458         index = bond_info->rx_hashtbl_head;
459         for (; index != RLB_NULL_INDEX; index = next_index) {
460                 next_index = rx_hash_table[index].next;
461                 if (rx_hash_table[index].slave == slave) {
462                         struct slave *assigned_slave = rlb_next_rx_slave(bond);
463
464                         if (assigned_slave) {
465                                 rx_hash_table[index].slave = assigned_slave;
466                                 if (memcmp(rx_hash_table[index].mac_dst,
467                                            mac_bcast, ETH_ALEN)) {
468                                         bond_info->rx_hashtbl[index].ntt = 1;
469                                         bond_info->rx_ntt = 1;
470                                         /* A slave has been removed from the
471                                          * table because it is either disabled
472                                          * or being released. We must retry the
473                                          * update to avoid clients from not
474                                          * being updated & disconnecting when
475                                          * there is stress
476                                          */
477                                         bond_info->rlb_update_retry_counter =
478                                                 RLB_UPDATE_RETRY;
479                                 }
480                         } else {  /* there is no active slave */
481                                 rx_hash_table[index].slave = NULL;
482                         }
483                 }
484         }
485
486         _unlock_rx_hashtbl(bond);
487
488         write_lock(&bond->curr_slave_lock);
489
490         if (slave != bond->curr_active_slave) {
491                 rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
492         }
493
494         write_unlock(&bond->curr_slave_lock);
495 }
496
497 static void rlb_update_client(struct rlb_client_info *client_info)
498 {
499         int i;
500
501         if (!client_info->slave) {
502                 return;
503         }
504
505         for (i = 0; i < RLB_ARP_BURST_SIZE; i++) {
506                 struct sk_buff *skb;
507
508                 skb = arp_create(ARPOP_REPLY, ETH_P_ARP,
509                                  client_info->ip_dst,
510                                  client_info->slave->dev,
511                                  client_info->ip_src,
512                                  client_info->mac_dst,
513                                  client_info->slave->dev->dev_addr,
514                                  client_info->mac_dst);
515                 if (!skb) {
516                         printk(KERN_ERR DRV_NAME
517                                ": %s: Error: failed to create an ARP packet\n",
518                                client_info->slave->dev->master->name);
519                         continue;
520                 }
521
522                 skb->dev = client_info->slave->dev;
523
524                 if (client_info->tag) {
525                         skb = vlan_put_tag(skb, client_info->vlan_id);
526                         if (!skb) {
527                                 printk(KERN_ERR DRV_NAME
528                                        ": %s: Error: failed to insert VLAN tag\n",
529                                        client_info->slave->dev->master->name);
530                                 continue;
531                         }
532                 }
533
534                 arp_xmit(skb);
535         }
536 }
537
538 /* sends ARP REPLIES that update the clients that need updating */
539 static void rlb_update_rx_clients(struct bonding *bond)
540 {
541         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
542         struct rlb_client_info *client_info;
543         u32 hash_index;
544
545         _lock_rx_hashtbl(bond);
546
547         hash_index = bond_info->rx_hashtbl_head;
548         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
549                 client_info = &(bond_info->rx_hashtbl[hash_index]);
550                 if (client_info->ntt) {
551                         rlb_update_client(client_info);
552                         if (bond_info->rlb_update_retry_counter == 0) {
553                                 client_info->ntt = 0;
554                         }
555                 }
556         }
557
558         /* do not update the entries again untill this counter is zero so that
559          * not to confuse the clients.
560          */
561         bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
562
563         _unlock_rx_hashtbl(bond);
564 }
565
566 /* The slave was assigned a new mac address - update the clients */
567 static void rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
568 {
569         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
570         struct rlb_client_info *client_info;
571         int ntt = 0;
572         u32 hash_index;
573
574         _lock_rx_hashtbl(bond);
575
576         hash_index = bond_info->rx_hashtbl_head;
577         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
578                 client_info = &(bond_info->rx_hashtbl[hash_index]);
579
580                 if ((client_info->slave == slave) &&
581                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
582                         client_info->ntt = 1;
583                         ntt = 1;
584                 }
585         }
586
587         // update the team's flag only after the whole iteration
588         if (ntt) {
589                 bond_info->rx_ntt = 1;
590                 //fasten the change
591                 bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
592         }
593
594         _unlock_rx_hashtbl(bond);
595 }
596
597 /* mark all clients using src_ip to be updated */
598 static void rlb_req_update_subnet_clients(struct bonding *bond, u32 src_ip)
599 {
600         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
601         struct rlb_client_info *client_info;
602         u32 hash_index;
603
604         _lock_rx_hashtbl(bond);
605
606         hash_index = bond_info->rx_hashtbl_head;
607         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
608                 client_info = &(bond_info->rx_hashtbl[hash_index]);
609
610                 if (!client_info->slave) {
611                         printk(KERN_ERR DRV_NAME
612                                ": %s: Error: found a client with no channel in "
613                                "the client's hash table\n",
614                                bond->dev->name);
615                         continue;
616                 }
617                 /*update all clients using this src_ip, that are not assigned
618                  * to the team's address (curr_active_slave) and have a known
619                  * unicast mac address.
620                  */
621                 if ((client_info->ip_src == src_ip) &&
622                     memcmp(client_info->slave->dev->dev_addr,
623                            bond->dev->dev_addr, ETH_ALEN) &&
624                     memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
625                         client_info->ntt = 1;
626                         bond_info->rx_ntt = 1;
627                 }
628         }
629
630         _unlock_rx_hashtbl(bond);
631 }
632
633 /* Caller must hold both bond and ptr locks for read */
634 static struct slave *rlb_choose_channel(struct sk_buff *skb, struct bonding *bond)
635 {
636         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
637         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
638         struct slave *assigned_slave;
639         struct rlb_client_info *client_info;
640         u32 hash_index = 0;
641
642         _lock_rx_hashtbl(bond);
643
644         hash_index = _simple_hash((u8 *)&arp->ip_dst, sizeof(arp->ip_src));
645         client_info = &(bond_info->rx_hashtbl[hash_index]);
646
647         if (client_info->assigned) {
648                 if ((client_info->ip_src == arp->ip_src) &&
649                     (client_info->ip_dst == arp->ip_dst)) {
650                         /* the entry is already assigned to this client */
651                         if (memcmp(arp->mac_dst, mac_bcast, ETH_ALEN)) {
652                                 /* update mac address from arp */
653                                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
654                         }
655
656                         assigned_slave = client_info->slave;
657                         if (assigned_slave) {
658                                 _unlock_rx_hashtbl(bond);
659                                 return assigned_slave;
660                         }
661                 } else {
662                         /* the entry is already assigned to some other client,
663                          * move the old client to primary (curr_active_slave) so
664                          * that the new client can be assigned to this entry.
665                          */
666                         if (bond->curr_active_slave &&
667                             client_info->slave != bond->curr_active_slave) {
668                                 client_info->slave = bond->curr_active_slave;
669                                 rlb_update_client(client_info);
670                         }
671                 }
672         }
673         /* assign a new slave */
674         assigned_slave = rlb_next_rx_slave(bond);
675
676         if (assigned_slave) {
677                 client_info->ip_src = arp->ip_src;
678                 client_info->ip_dst = arp->ip_dst;
679                 /* arp->mac_dst is broadcast for arp reqeusts.
680                  * will be updated with clients actual unicast mac address
681                  * upon receiving an arp reply.
682                  */
683                 memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
684                 client_info->slave = assigned_slave;
685
686                 if (memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
687                         client_info->ntt = 1;
688                         bond->alb_info.rx_ntt = 1;
689                 } else {
690                         client_info->ntt = 0;
691                 }
692
693                 if (!list_empty(&bond->vlan_list)) {
694                         unsigned short vlan_id;
695                         int res = vlan_get_tag(skb, &vlan_id);
696                         if (!res) {
697                                 client_info->tag = 1;
698                                 client_info->vlan_id = vlan_id;
699                         }
700                 }
701
702                 if (!client_info->assigned) {
703                         u32 prev_tbl_head = bond_info->rx_hashtbl_head;
704                         bond_info->rx_hashtbl_head = hash_index;
705                         client_info->next = prev_tbl_head;
706                         if (prev_tbl_head != RLB_NULL_INDEX) {
707                                 bond_info->rx_hashtbl[prev_tbl_head].prev =
708                                         hash_index;
709                         }
710                         client_info->assigned = 1;
711                 }
712         }
713
714         _unlock_rx_hashtbl(bond);
715
716         return assigned_slave;
717 }
718
719 /* chooses (and returns) transmit channel for arp reply
720  * does not choose channel for other arp types since they are
721  * sent on the curr_active_slave
722  */
723 static struct slave *rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
724 {
725         struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
726         struct slave *tx_slave = NULL;
727
728         if (arp->op_code == __constant_htons(ARPOP_REPLY)) {
729                 /* the arp must be sent on the selected
730                 * rx channel
731                 */
732                 tx_slave = rlb_choose_channel(skb, bond);
733                 if (tx_slave) {
734                         memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
735                 }
736                 dprintk("Server sent ARP Reply packet\n");
737         } else if (arp->op_code == __constant_htons(ARPOP_REQUEST)) {
738                 /* Create an entry in the rx_hashtbl for this client as a
739                  * place holder.
740                  * When the arp reply is received the entry will be updated
741                  * with the correct unicast address of the client.
742                  */
743                 rlb_choose_channel(skb, bond);
744
745                 /* The ARP relpy packets must be delayed so that
746                  * they can cancel out the influence of the ARP request.
747                  */
748                 bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
749
750                 /* arp requests are broadcast and are sent on the primary
751                  * the arp request will collapse all clients on the subnet to
752                  * the primary slave. We must register these clients to be
753                  * updated with their assigned mac.
754                  */
755                 rlb_req_update_subnet_clients(bond, arp->ip_src);
756                 dprintk("Server sent ARP Request packet\n");
757         }
758
759         return tx_slave;
760 }
761
762 /* Caller must hold bond lock for read */
763 static void rlb_rebalance(struct bonding *bond)
764 {
765         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
766         struct slave *assigned_slave;
767         struct rlb_client_info *client_info;
768         int ntt;
769         u32 hash_index;
770
771         _lock_rx_hashtbl(bond);
772
773         ntt = 0;
774         hash_index = bond_info->rx_hashtbl_head;
775         for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
776                 client_info = &(bond_info->rx_hashtbl[hash_index]);
777                 assigned_slave = rlb_next_rx_slave(bond);
778                 if (assigned_slave && (client_info->slave != assigned_slave)) {
779                         client_info->slave = assigned_slave;
780                         client_info->ntt = 1;
781                         ntt = 1;
782                 }
783         }
784
785         /* update the team's flag only after the whole iteration */
786         if (ntt) {
787                 bond_info->rx_ntt = 1;
788         }
789         _unlock_rx_hashtbl(bond);
790 }
791
792 /* Caller must hold rx_hashtbl lock */
793 static void rlb_init_table_entry(struct rlb_client_info *entry)
794 {
795         memset(entry, 0, sizeof(struct rlb_client_info));
796         entry->next = RLB_NULL_INDEX;
797         entry->prev = RLB_NULL_INDEX;
798 }
799
800 static int rlb_initialize(struct bonding *bond)
801 {
802         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
803         struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
804         struct rlb_client_info  *new_hashtbl;
805         int size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
806         int i;
807
808         spin_lock_init(&(bond_info->rx_hashtbl_lock));
809
810         new_hashtbl = kmalloc(size, GFP_KERNEL);
811         if (!new_hashtbl) {
812                 printk(KERN_ERR DRV_NAME
813                        ": %s: Error: Failed to allocate RLB hash table\n",
814                        bond->dev->name);
815                 return -1;
816         }
817         _lock_rx_hashtbl(bond);
818
819         bond_info->rx_hashtbl = new_hashtbl;
820
821         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
822
823         for (i = 0; i < RLB_HASH_TABLE_SIZE; i++) {
824                 rlb_init_table_entry(bond_info->rx_hashtbl + i);
825         }
826
827         _unlock_rx_hashtbl(bond);
828
829         /*initialize packet type*/
830         pk_type->type = __constant_htons(ETH_P_ARP);
831         pk_type->dev = bond->dev;
832         pk_type->func = rlb_arp_recv;
833
834         /* register to receive ARPs */
835         dev_add_pack(pk_type);
836
837         return 0;
838 }
839
840 static void rlb_deinitialize(struct bonding *bond)
841 {
842         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
843
844         dev_remove_pack(&(bond_info->rlb_pkt_type));
845
846         _lock_rx_hashtbl(bond);
847
848         kfree(bond_info->rx_hashtbl);
849         bond_info->rx_hashtbl = NULL;
850         bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
851
852         _unlock_rx_hashtbl(bond);
853 }
854
855 static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
856 {
857         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
858         u32 curr_index;
859
860         _lock_rx_hashtbl(bond);
861
862         curr_index = bond_info->rx_hashtbl_head;
863         while (curr_index != RLB_NULL_INDEX) {
864                 struct rlb_client_info *curr = &(bond_info->rx_hashtbl[curr_index]);
865                 u32 next_index = bond_info->rx_hashtbl[curr_index].next;
866                 u32 prev_index = bond_info->rx_hashtbl[curr_index].prev;
867
868                 if (curr->tag && (curr->vlan_id == vlan_id)) {
869                         if (curr_index == bond_info->rx_hashtbl_head) {
870                                 bond_info->rx_hashtbl_head = next_index;
871                         }
872                         if (prev_index != RLB_NULL_INDEX) {
873                                 bond_info->rx_hashtbl[prev_index].next = next_index;
874                         }
875                         if (next_index != RLB_NULL_INDEX) {
876                                 bond_info->rx_hashtbl[next_index].prev = prev_index;
877                         }
878
879                         rlb_init_table_entry(curr);
880                 }
881
882                 curr_index = next_index;
883         }
884
885         _unlock_rx_hashtbl(bond);
886 }
887
888 /*********************** tlb/rlb shared functions *********************/
889
890 static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
891 {
892         struct bonding *bond = bond_get_bond_by_slave(slave);
893         struct learning_pkt pkt;
894         int size = sizeof(struct learning_pkt);
895         int i;
896
897         memset(&pkt, 0, size);
898         memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
899         memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
900         pkt.type = __constant_htons(ETH_P_LOOP);
901
902         for (i = 0; i < MAX_LP_BURST; i++) {
903                 struct sk_buff *skb;
904                 char *data;
905
906                 skb = dev_alloc_skb(size);
907                 if (!skb) {
908                         return;
909                 }
910
911                 data = skb_put(skb, size);
912                 memcpy(data, &pkt, size);
913
914                 skb->mac.raw = data;
915                 skb->nh.raw = data + ETH_HLEN;
916                 skb->protocol = pkt.type;
917                 skb->priority = TC_PRIO_CONTROL;
918                 skb->dev = slave->dev;
919
920                 if (!list_empty(&bond->vlan_list)) {
921                         struct vlan_entry *vlan;
922
923                         vlan = bond_next_vlan(bond,
924                                               bond->alb_info.current_alb_vlan);
925
926                         bond->alb_info.current_alb_vlan = vlan;
927                         if (!vlan) {
928                                 kfree_skb(skb);
929                                 continue;
930                         }
931
932                         skb = vlan_put_tag(skb, vlan->vlan_id);
933                         if (!skb) {
934                                 printk(KERN_ERR DRV_NAME
935                                        ": %s: Error: failed to insert VLAN tag\n",
936                                        bond->dev->name);
937                                 continue;
938                         }
939                 }
940
941                 dev_queue_xmit(skb);
942         }
943 }
944
945 /* hw is a boolean parameter that determines whether we should try and
946  * set the hw address of the device as well as the hw address of the
947  * net_device
948  */
949 static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[], int hw)
950 {
951         struct net_device *dev = slave->dev;
952         struct sockaddr s_addr;
953
954         if (!hw) {
955                 memcpy(dev->dev_addr, addr, dev->addr_len);
956                 return 0;
957         }
958
959         /* for rlb each slave must have a unique hw mac addresses so that */
960         /* each slave will receive packets destined to a different mac */
961         memcpy(s_addr.sa_data, addr, dev->addr_len);
962         s_addr.sa_family = dev->type;
963         if (dev_set_mac_address(dev, &s_addr)) {
964                 printk(KERN_ERR DRV_NAME
965                        ": %s: Error: dev_set_mac_address of dev %s failed! ALB "
966                        "mode requires that the base driver support setting "
967                        "the hw address also when the network device's "
968                        "interface is open\n",
969                        dev->master->name, dev->name);
970                 return -EOPNOTSUPP;
971         }
972         return 0;
973 }
974
975 /* Caller must hold bond lock for write or curr_slave_lock for write*/
976 static void alb_swap_mac_addr(struct bonding *bond, struct slave *slave1, struct slave *slave2)
977 {
978         struct slave *disabled_slave = NULL;
979         u8 tmp_mac_addr[ETH_ALEN];
980         int slaves_state_differ;
981
982         slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
983
984         memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
985         alb_set_slave_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
986         alb_set_slave_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
987
988         /* fasten the change in the switch */
989         if (SLAVE_IS_OK(slave1)) {
990                 alb_send_learning_packets(slave1, slave1->dev->dev_addr);
991                 if (bond->alb_info.rlb_enabled) {
992                         /* inform the clients that the mac address
993                          * has changed
994                          */
995                         rlb_req_update_slave_clients(bond, slave1);
996                 }
997         } else {
998                 disabled_slave = slave1;
999         }
1000
1001         if (SLAVE_IS_OK(slave2)) {
1002                 alb_send_learning_packets(slave2, slave2->dev->dev_addr);
1003                 if (bond->alb_info.rlb_enabled) {
1004                         /* inform the clients that the mac address
1005                          * has changed
1006                          */
1007                         rlb_req_update_slave_clients(bond, slave2);
1008                 }
1009         } else {
1010                 disabled_slave = slave2;
1011         }
1012
1013         if (bond->alb_info.rlb_enabled && slaves_state_differ) {
1014                 /* A disabled slave was assigned an active mac addr */
1015                 rlb_teach_disabled_mac_on_primary(bond,
1016                                                   disabled_slave->dev->dev_addr);
1017         }
1018 }
1019
1020 /**
1021  * alb_change_hw_addr_on_detach
1022  * @bond: bonding we're working on
1023  * @slave: the slave that was just detached
1024  *
1025  * We assume that @slave was already detached from the slave list.
1026  *
1027  * If @slave's permanent hw address is different both from its current
1028  * address and from @bond's address, then somewhere in the bond there's
1029  * a slave that has @slave's permanet address as its current address.
1030  * We'll make sure that that slave no longer uses @slave's permanent address.
1031  *
1032  * Caller must hold bond lock
1033  */
1034 static void alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
1035 {
1036         int perm_curr_diff;
1037         int perm_bond_diff;
1038
1039         perm_curr_diff = memcmp(slave->perm_hwaddr,
1040                                 slave->dev->dev_addr,
1041                                 ETH_ALEN);
1042         perm_bond_diff = memcmp(slave->perm_hwaddr,
1043                                 bond->dev->dev_addr,
1044                                 ETH_ALEN);
1045
1046         if (perm_curr_diff && perm_bond_diff) {
1047                 struct slave *tmp_slave;
1048                 int i, found = 0;
1049
1050                 bond_for_each_slave(bond, tmp_slave, i) {
1051                         if (!memcmp(slave->perm_hwaddr,
1052                                     tmp_slave->dev->dev_addr,
1053                                     ETH_ALEN)) {
1054                                 found = 1;
1055                                 break;
1056                         }
1057                 }
1058
1059                 if (found) {
1060                         alb_swap_mac_addr(bond, slave, tmp_slave);
1061                 }
1062         }
1063 }
1064
1065 /**
1066  * alb_handle_addr_collision_on_attach
1067  * @bond: bonding we're working on
1068  * @slave: the slave that was just attached
1069  *
1070  * checks uniqueness of slave's mac address and handles the case the
1071  * new slave uses the bonds mac address.
1072  *
1073  * If the permanent hw address of @slave is @bond's hw address, we need to
1074  * find a different hw address to give @slave, that isn't in use by any other
1075  * slave in the bond. This address must be, of course, one of the premanent
1076  * addresses of the other slaves.
1077  *
1078  * We go over the slave list, and for each slave there we compare its
1079  * permanent hw address with the current address of all the other slaves.
1080  * If no match was found, then we've found a slave with a permanent address
1081  * that isn't used by any other slave in the bond, so we can assign it to
1082  * @slave.
1083  *
1084  * assumption: this function is called before @slave is attached to the
1085  *             bond slave list.
1086  *
1087  * caller must hold the bond lock for write since the mac addresses are compared
1088  * and may be swapped.
1089  */
1090 static int alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
1091 {
1092         struct slave *tmp_slave1, *tmp_slave2, *free_mac_slave;
1093         struct slave *has_bond_addr = bond->curr_active_slave;
1094         int i, j, found = 0;
1095
1096         if (bond->slave_cnt == 0) {
1097                 /* this is the first slave */
1098                 return 0;
1099         }
1100
1101         /* if slave's mac address differs from bond's mac address
1102          * check uniqueness of slave's mac address against the other
1103          * slaves in the bond.
1104          */
1105         if (memcmp(slave->perm_hwaddr, bond->dev->dev_addr, ETH_ALEN)) {
1106                 bond_for_each_slave(bond, tmp_slave1, i) {
1107                         if (!memcmp(tmp_slave1->dev->dev_addr, slave->dev->dev_addr,
1108                                     ETH_ALEN)) {
1109                                 found = 1;
1110                                 break;
1111                         }
1112                 }
1113
1114                 if (!found)
1115                         return 0;
1116
1117                 /* Try setting slave mac to bond address and fall-through
1118                    to code handling that situation below... */
1119                 alb_set_slave_mac_addr(slave, bond->dev->dev_addr,
1120                                        bond->alb_info.rlb_enabled);
1121         }
1122
1123         /* The slave's address is equal to the address of the bond.
1124          * Search for a spare address in the bond for this slave.
1125          */
1126         free_mac_slave = NULL;
1127
1128         bond_for_each_slave(bond, tmp_slave1, i) {
1129                 found = 0;
1130                 bond_for_each_slave(bond, tmp_slave2, j) {
1131                         if (!memcmp(tmp_slave1->perm_hwaddr,
1132                                     tmp_slave2->dev->dev_addr,
1133                                     ETH_ALEN)) {
1134                                 found = 1;
1135                                 break;
1136                         }
1137                 }
1138
1139                 if (!found) {
1140                         /* no slave has tmp_slave1's perm addr
1141                          * as its curr addr
1142                          */
1143                         free_mac_slave = tmp_slave1;
1144                         break;
1145                 }
1146
1147                 if (!has_bond_addr) {
1148                         if (!memcmp(tmp_slave1->dev->dev_addr,
1149                                     bond->dev->dev_addr,
1150                                     ETH_ALEN)) {
1151
1152                                 has_bond_addr = tmp_slave1;
1153                         }
1154                 }
1155         }
1156
1157         if (free_mac_slave) {
1158                 alb_set_slave_mac_addr(slave, free_mac_slave->perm_hwaddr,
1159                                        bond->alb_info.rlb_enabled);
1160
1161                 printk(KERN_WARNING DRV_NAME
1162                        ": %s: Warning: the hw address of slave %s is in use by "
1163                        "the bond; giving it the hw address of %s\n",
1164                        bond->dev->name, slave->dev->name, free_mac_slave->dev->name);
1165
1166         } else if (has_bond_addr) {
1167                 printk(KERN_ERR DRV_NAME
1168                        ": %s: Error: the hw address of slave %s is in use by the "
1169                        "bond; couldn't find a slave with a free hw address to "
1170                        "give it (this should not have happened)\n",
1171                        bond->dev->name, slave->dev->name);
1172                 return -EFAULT;
1173         }
1174
1175         return 0;
1176 }
1177
1178 /**
1179  * alb_set_mac_address
1180  * @bond:
1181  * @addr:
1182  *
1183  * In TLB mode all slaves are configured to the bond's hw address, but set
1184  * their dev_addr field to different addresses (based on their permanent hw
1185  * addresses).
1186  *
1187  * For each slave, this function sets the interface to the new address and then
1188  * changes its dev_addr field to its previous value.
1189  *
1190  * Unwinding assumes bond's mac address has not yet changed.
1191  */
1192 static int alb_set_mac_address(struct bonding *bond, void *addr)
1193 {
1194         struct sockaddr sa;
1195         struct slave *slave, *stop_at;
1196         char tmp_addr[ETH_ALEN];
1197         int res;
1198         int i;
1199
1200         if (bond->alb_info.rlb_enabled) {
1201                 return 0;
1202         }
1203
1204         bond_for_each_slave(bond, slave, i) {
1205                 if (slave->dev->set_mac_address == NULL) {
1206                         res = -EOPNOTSUPP;
1207                         goto unwind;
1208                 }
1209
1210                 /* save net_device's current hw address */
1211                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1212
1213                 res = dev_set_mac_address(slave->dev, addr);
1214
1215                 /* restore net_device's hw address */
1216                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1217
1218                 if (res) {
1219                         goto unwind;
1220                 }
1221         }
1222
1223         return 0;
1224
1225 unwind:
1226         memcpy(sa.sa_data, bond->dev->dev_addr, bond->dev->addr_len);
1227         sa.sa_family = bond->dev->type;
1228
1229         /* unwind from head to the slave that failed */
1230         stop_at = slave;
1231         bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
1232                 memcpy(tmp_addr, slave->dev->dev_addr, ETH_ALEN);
1233                 dev_set_mac_address(slave->dev, &sa);
1234                 memcpy(slave->dev->dev_addr, tmp_addr, ETH_ALEN);
1235         }
1236
1237         return res;
1238 }
1239
1240 /************************ exported alb funcions ************************/
1241
1242 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
1243 {
1244         int res;
1245
1246         res = tlb_initialize(bond);
1247         if (res) {
1248                 return res;
1249         }
1250
1251         if (rlb_enabled) {
1252                 bond->alb_info.rlb_enabled = 1;
1253                 /* initialize rlb */
1254                 res = rlb_initialize(bond);
1255                 if (res) {
1256                         tlb_deinitialize(bond);
1257                         return res;
1258                 }
1259         }
1260
1261         return 0;
1262 }
1263
1264 void bond_alb_deinitialize(struct bonding *bond)
1265 {
1266         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1267
1268         tlb_deinitialize(bond);
1269
1270         if (bond_info->rlb_enabled) {
1271                 rlb_deinitialize(bond);
1272         }
1273 }
1274
1275 int bond_alb_xmit(struct sk_buff *skb, struct net_device *bond_dev)
1276 {
1277         struct bonding *bond = bond_dev->priv;
1278         struct ethhdr *eth_data;
1279         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1280         struct slave *tx_slave = NULL;
1281         static u32 ip_bcast = 0xffffffff;
1282         int hash_size = 0;
1283         int do_tx_balance = 1;
1284         u32 hash_index = 0;
1285         u8 *hash_start = NULL;
1286         int res = 1;
1287
1288         skb->mac.raw = (unsigned char *)skb->data;
1289         eth_data = eth_hdr(skb);
1290
1291         /* make sure that the curr_active_slave and the slaves list do
1292          * not change during tx
1293          */
1294         read_lock(&bond->lock);
1295         read_lock(&bond->curr_slave_lock);
1296
1297         if (!BOND_IS_OK(bond)) {
1298                 goto out;
1299         }
1300
1301         switch (ntohs(skb->protocol)) {
1302         case ETH_P_IP:
1303                 if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
1304                     (skb->nh.iph->daddr == ip_bcast) ||
1305                     (skb->nh.iph->protocol == IPPROTO_IGMP)) {
1306                         do_tx_balance = 0;
1307                         break;
1308                 }
1309                 hash_start = (char*)&(skb->nh.iph->daddr);
1310                 hash_size = sizeof(skb->nh.iph->daddr);
1311                 break;
1312         case ETH_P_IPV6:
1313                 if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
1314                         do_tx_balance = 0;
1315                         break;
1316                 }
1317
1318                 hash_start = (char*)&(skb->nh.ipv6h->daddr);
1319                 hash_size = sizeof(skb->nh.ipv6h->daddr);
1320                 break;
1321         case ETH_P_IPX:
1322                 if (ipx_hdr(skb)->ipx_checksum !=
1323                     __constant_htons(IPX_NO_CHECKSUM)) {
1324                         /* something is wrong with this packet */
1325                         do_tx_balance = 0;
1326                         break;
1327                 }
1328
1329                 if (ipx_hdr(skb)->ipx_type != IPX_TYPE_NCP) {
1330                         /* The only protocol worth balancing in
1331                          * this family since it has an "ARP" like
1332                          * mechanism
1333                          */
1334                         do_tx_balance = 0;
1335                         break;
1336                 }
1337
1338                 hash_start = (char*)eth_data->h_dest;
1339                 hash_size = ETH_ALEN;
1340                 break;
1341         case ETH_P_ARP:
1342                 do_tx_balance = 0;
1343                 if (bond_info->rlb_enabled) {
1344                         tx_slave = rlb_arp_xmit(skb, bond);
1345                 }
1346                 break;
1347         default:
1348                 do_tx_balance = 0;
1349                 break;
1350         }
1351
1352         if (do_tx_balance) {
1353                 hash_index = _simple_hash(hash_start, hash_size);
1354                 tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
1355         }
1356
1357         if (!tx_slave) {
1358                 /* unbalanced or unassigned, send through primary */
1359                 tx_slave = bond->curr_active_slave;
1360                 bond_info->unbalanced_load += skb->len;
1361         }
1362
1363         if (tx_slave && SLAVE_IS_OK(tx_slave)) {
1364                 if (tx_slave != bond->curr_active_slave) {
1365                         memcpy(eth_data->h_source,
1366                                tx_slave->dev->dev_addr,
1367                                ETH_ALEN);
1368                 }
1369
1370                 res = bond_dev_queue_xmit(bond, skb, tx_slave->dev);
1371         } else {
1372                 if (tx_slave) {
1373                         tlb_clear_slave(bond, tx_slave, 0);
1374                 }
1375         }
1376
1377 out:
1378         if (res) {
1379                 /* no suitable interface, frame not sent */
1380                 dev_kfree_skb(skb);
1381         }
1382         read_unlock(&bond->curr_slave_lock);
1383         read_unlock(&bond->lock);
1384         return 0;
1385 }
1386
1387 void bond_alb_monitor(struct bonding *bond)
1388 {
1389         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1390         struct slave *slave;
1391         int i;
1392
1393         read_lock(&bond->lock);
1394
1395         if (bond->kill_timers) {
1396                 goto out;
1397         }
1398
1399         if (bond->slave_cnt == 0) {
1400                 bond_info->tx_rebalance_counter = 0;
1401                 bond_info->lp_counter = 0;
1402                 goto re_arm;
1403         }
1404
1405         bond_info->tx_rebalance_counter++;
1406         bond_info->lp_counter++;
1407
1408         /* send learning packets */
1409         if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
1410                 /* change of curr_active_slave involves swapping of mac addresses.
1411                  * in order to avoid this swapping from happening while
1412                  * sending the learning packets, the curr_slave_lock must be held for
1413                  * read.
1414                  */
1415                 read_lock(&bond->curr_slave_lock);
1416
1417                 bond_for_each_slave(bond, slave, i) {
1418                         alb_send_learning_packets(slave,slave->dev->dev_addr);
1419                 }
1420
1421                 read_unlock(&bond->curr_slave_lock);
1422
1423                 bond_info->lp_counter = 0;
1424         }
1425
1426         /* rebalance tx traffic */
1427         if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
1428
1429                 read_lock(&bond->curr_slave_lock);
1430
1431                 bond_for_each_slave(bond, slave, i) {
1432                         tlb_clear_slave(bond, slave, 1);
1433                         if (slave == bond->curr_active_slave) {
1434                                 SLAVE_TLB_INFO(slave).load =
1435                                         bond_info->unbalanced_load /
1436                                                 BOND_TLB_REBALANCE_INTERVAL;
1437                                 bond_info->unbalanced_load = 0;
1438                         }
1439                 }
1440
1441                 read_unlock(&bond->curr_slave_lock);
1442
1443                 bond_info->tx_rebalance_counter = 0;
1444         }
1445
1446         /* handle rlb stuff */
1447         if (bond_info->rlb_enabled) {
1448                 /* the following code changes the promiscuity of the
1449                  * the curr_active_slave. It needs to be locked with a
1450                  * write lock to protect from other code that also
1451                  * sets the promiscuity.
1452                  */
1453                 write_lock(&bond->curr_slave_lock);
1454
1455                 if (bond_info->primary_is_promisc &&
1456                     (++bond_info->rlb_promisc_timeout_counter >= RLB_PROMISC_TIMEOUT)) {
1457
1458                         bond_info->rlb_promisc_timeout_counter = 0;
1459
1460                         /* If the primary was set to promiscuous mode
1461                          * because a slave was disabled then
1462                          * it can now leave promiscuous mode.
1463                          */
1464                         dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1465                         bond_info->primary_is_promisc = 0;
1466                 }
1467
1468                 write_unlock(&bond->curr_slave_lock);
1469
1470                 if (bond_info->rlb_rebalance) {
1471                         bond_info->rlb_rebalance = 0;
1472                         rlb_rebalance(bond);
1473                 }
1474
1475                 /* check if clients need updating */
1476                 if (bond_info->rx_ntt) {
1477                         if (bond_info->rlb_update_delay_counter) {
1478                                 --bond_info->rlb_update_delay_counter;
1479                         } else {
1480                                 rlb_update_rx_clients(bond);
1481                                 if (bond_info->rlb_update_retry_counter) {
1482                                         --bond_info->rlb_update_retry_counter;
1483                                 } else {
1484                                         bond_info->rx_ntt = 0;
1485                                 }
1486                         }
1487                 }
1488         }
1489
1490 re_arm:
1491         mod_timer(&(bond_info->alb_timer), jiffies + alb_delta_in_ticks);
1492 out:
1493         read_unlock(&bond->lock);
1494 }
1495
1496 /* assumption: called before the slave is attached to the bond
1497  * and not locked by the bond lock
1498  */
1499 int bond_alb_init_slave(struct bonding *bond, struct slave *slave)
1500 {
1501         int res;
1502
1503         res = alb_set_slave_mac_addr(slave, slave->perm_hwaddr,
1504                                      bond->alb_info.rlb_enabled);
1505         if (res) {
1506                 return res;
1507         }
1508
1509         /* caller must hold the bond lock for write since the mac addresses
1510          * are compared and may be swapped.
1511          */
1512         write_lock_bh(&bond->lock);
1513
1514         res = alb_handle_addr_collision_on_attach(bond, slave);
1515
1516         write_unlock_bh(&bond->lock);
1517
1518         if (res) {
1519                 return res;
1520         }
1521
1522         tlb_init_slave(slave);
1523
1524         /* order a rebalance ASAP */
1525         bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1526
1527         if (bond->alb_info.rlb_enabled) {
1528                 bond->alb_info.rlb_rebalance = 1;
1529         }
1530
1531         return 0;
1532 }
1533
1534 /* Caller must hold bond lock for write */
1535 void bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
1536 {
1537         if (bond->slave_cnt > 1) {
1538                 alb_change_hw_addr_on_detach(bond, slave);
1539         }
1540
1541         tlb_clear_slave(bond, slave, 0);
1542
1543         if (bond->alb_info.rlb_enabled) {
1544                 bond->alb_info.next_rx_slave = NULL;
1545                 rlb_clear_slave(bond, slave);
1546         }
1547 }
1548
1549 /* Caller must hold bond lock for read */
1550 void bond_alb_handle_link_change(struct bonding *bond, struct slave *slave, char link)
1551 {
1552         struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
1553
1554         if (link == BOND_LINK_DOWN) {
1555                 tlb_clear_slave(bond, slave, 0);
1556                 if (bond->alb_info.rlb_enabled) {
1557                         rlb_clear_slave(bond, slave);
1558                 }
1559         } else if (link == BOND_LINK_UP) {
1560                 /* order a rebalance ASAP */
1561                 bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
1562                 if (bond->alb_info.rlb_enabled) {
1563                         bond->alb_info.rlb_rebalance = 1;
1564                         /* If the updelay module parameter is smaller than the
1565                          * forwarding delay of the switch the rebalance will
1566                          * not work because the rebalance arp replies will
1567                          * not be forwarded to the clients..
1568                          */
1569                 }
1570         }
1571 }
1572
1573 /**
1574  * bond_alb_handle_active_change - assign new curr_active_slave
1575  * @bond: our bonding struct
1576  * @new_slave: new slave to assign
1577  *
1578  * Set the bond->curr_active_slave to @new_slave and handle
1579  * mac address swapping and promiscuity changes as needed.
1580  *
1581  * Caller must hold bond curr_slave_lock for write (or bond lock for write)
1582  */
1583 void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave)
1584 {
1585         struct slave *swap_slave;
1586         int i;
1587
1588         if (bond->curr_active_slave == new_slave) {
1589                 return;
1590         }
1591
1592         if (bond->curr_active_slave && bond->alb_info.primary_is_promisc) {
1593                 dev_set_promiscuity(bond->curr_active_slave->dev, -1);
1594                 bond->alb_info.primary_is_promisc = 0;
1595                 bond->alb_info.rlb_promisc_timeout_counter = 0;
1596         }
1597
1598         swap_slave = bond->curr_active_slave;
1599         bond->curr_active_slave = new_slave;
1600
1601         if (!new_slave || (bond->slave_cnt == 0)) {
1602                 return;
1603         }
1604
1605         /* set the new curr_active_slave to the bonds mac address
1606          * i.e. swap mac addresses of old curr_active_slave and new curr_active_slave
1607          */
1608         if (!swap_slave) {
1609                 struct slave *tmp_slave;
1610                 /* find slave that is holding the bond's mac address */
1611                 bond_for_each_slave(bond, tmp_slave, i) {
1612                         if (!memcmp(tmp_slave->dev->dev_addr,
1613                                     bond->dev->dev_addr, ETH_ALEN)) {
1614                                 swap_slave = tmp_slave;
1615                                 break;
1616                         }
1617                 }
1618         }
1619
1620         /* curr_active_slave must be set before calling alb_swap_mac_addr */
1621         if (swap_slave) {
1622                 /* swap mac address */
1623                 alb_swap_mac_addr(bond, swap_slave, new_slave);
1624         } else {
1625                 /* set the new_slave to the bond mac address */
1626                 alb_set_slave_mac_addr(new_slave, bond->dev->dev_addr,
1627                                        bond->alb_info.rlb_enabled);
1628                 /* fasten bond mac on new current slave */
1629                 alb_send_learning_packets(new_slave, bond->dev->dev_addr);
1630         }
1631 }
1632
1633 int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
1634 {
1635         struct bonding *bond = bond_dev->priv;
1636         struct sockaddr *sa = addr;
1637         struct slave *slave, *swap_slave;
1638         int res;
1639         int i;
1640
1641         if (!is_valid_ether_addr(sa->sa_data)) {
1642                 return -EADDRNOTAVAIL;
1643         }
1644
1645         res = alb_set_mac_address(bond, addr);
1646         if (res) {
1647                 return res;
1648         }
1649
1650         memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
1651
1652         /* If there is no curr_active_slave there is nothing else to do.
1653          * Otherwise we'll need to pass the new address to it and handle
1654          * duplications.
1655          */
1656         if (!bond->curr_active_slave) {
1657                 return 0;
1658         }
1659
1660         swap_slave = NULL;
1661
1662         bond_for_each_slave(bond, slave, i) {
1663                 if (!memcmp(slave->dev->dev_addr, bond_dev->dev_addr, ETH_ALEN)) {
1664                         swap_slave = slave;
1665                         break;
1666                 }
1667         }
1668
1669         if (swap_slave) {
1670                 alb_swap_mac_addr(bond, swap_slave, bond->curr_active_slave);
1671         } else {
1672                 alb_set_slave_mac_addr(bond->curr_active_slave, bond_dev->dev_addr,
1673                                        bond->alb_info.rlb_enabled);
1674
1675                 alb_send_learning_packets(bond->curr_active_slave, bond_dev->dev_addr);
1676                 if (bond->alb_info.rlb_enabled) {
1677                         /* inform clients mac address has changed */
1678                         rlb_req_update_slave_clients(bond, bond->curr_active_slave);
1679                 }
1680         }
1681
1682         return 0;
1683 }
1684
1685 void bond_alb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
1686 {
1687         if (bond->alb_info.current_alb_vlan &&
1688             (bond->alb_info.current_alb_vlan->vlan_id == vlan_id)) {
1689                 bond->alb_info.current_alb_vlan = NULL;
1690         }
1691
1692         if (bond->alb_info.rlb_enabled) {
1693                 rlb_clear_vlan(bond, vlan_id);
1694         }
1695 }
1696