blob: 7266f6dbdd955710bab92d2336ba1be1516c701a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Equalizer Load-balancer for serial network interfaces.
3 *
4 * (c) Copyright 1995 Simon "Guru Aleph-Null" Janes
5 * NCM: Network and Communications Management, Inc.
6 *
7 * (c) Copyright 2002 David S. Miller (davem@redhat.com)
8 *
9 * This software may be used and distributed according to the terms
10 * of the GNU General Public License, incorporated herein by reference.
Jeff Garzik6aa20a22006-09-13 13:24:59 -040011 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * The author may be reached as simon@ncm.com, or C/O
13 * NCM
14 * Attn: Simon Janes
15 * 6803 Whittier Ave
16 * McLean VA 22101
17 * Phone: 1-703-847-0040 ext 103
18 */
19
20/*
21 * Sources:
22 * skeleton.c by Donald Becker.
23 * Inspirations:
24 * The Harried and Overworked Alan Cox
25 * Conspiracies:
Jeff Garzik6aa20a22006-09-13 13:24:59 -040026 * The Alan Cox and Mike McLagan plot to get someone else to do the code,
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 * which turned out to be me.
28 */
29
30/*
31 * $Log: eql.c,v $
32 * Revision 1.2 1996/04/11 17:51:52 guru
33 * Added one-line eql_remove_slave patch.
34 *
35 * Revision 1.1 1996/04/11 17:44:17 guru
36 * Initial revision
37 *
38 * Revision 3.13 1996/01/21 15:17:18 alan
39 * tx_queue_len changes.
40 * reformatted.
41 *
42 * Revision 3.12 1995/03/22 21:07:51 anarchy
43 * Added capable() checks on configuration.
44 * Moved header file.
45 *
46 * Revision 3.11 1995/01/19 23:14:31 guru
47 * slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
48 * (priority_Bps) + bytes_queued * 8;
49 *
50 * Revision 3.10 1995/01/19 23:07:53 guru
51 * back to
52 * slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
53 * (priority_Bps) + bytes_queued;
54 *
55 * Revision 3.9 1995/01/19 22:38:20 guru
56 * slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
57 * (priority_Bps) + bytes_queued * 4;
58 *
59 * Revision 3.8 1995/01/19 22:30:55 guru
60 * slave_load = (ULONG_MAX - (ULONG_MAX / 2)) -
61 * (priority_Bps) + bytes_queued * 2;
62 *
63 * Revision 3.7 1995/01/19 21:52:35 guru
64 * printk's trimmed out.
65 *
66 * Revision 3.6 1995/01/19 21:49:56 guru
67 * This is working pretty well. I gained 1 K/s in speed.. now it's just
68 * robustness and printk's to be diked out.
69 *
70 * Revision 3.5 1995/01/18 22:29:59 guru
71 * still crashes the kernel when the lock_wait thing is woken up.
72 *
73 * Revision 3.4 1995/01/18 21:59:47 guru
74 * Broken set-bit locking snapshot
75 *
76 * Revision 3.3 1995/01/17 22:09:18 guru
77 * infinite sleep in a lock somewhere..
78 *
79 * Revision 3.2 1995/01/15 16:46:06 guru
80 * Log trimmed of non-pertinent 1.x branch messages
81 *
82 * Revision 3.1 1995/01/15 14:41:45 guru
83 * New Scheduler and timer stuff...
84 *
85 * Revision 1.15 1995/01/15 14:29:02 guru
86 * Will make 1.14 (now 1.15) the 3.0 branch, and the 1.12 the 2.0 branch, the one
87 * with the dumber scheduler
88 *
89 * Revision 1.14 1995/01/15 02:37:08 guru
90 * shock.. the kept-new-versions could have zonked working
91 * stuff.. shudder
92 *
93 * Revision 1.13 1995/01/15 02:36:31 guru
94 * big changes
95 *
96 * scheduler was torn out and replaced with something smarter
97 *
98 * global names not prefixed with eql_ were renamed to protect
99 * against namespace collisions
100 *
101 * a few more abstract interfaces were added to facilitate any
102 * potential change of datastructure. the driver is still using
103 * a linked list of slaves. going to a heap would be a bit of
104 * an overkill.
105 *
106 * this compiles fine with no warnings.
107 *
108 * the locking mechanism and timer stuff must be written however,
109 * this version will not work otherwise
110 *
111 * Sorry, I had to rewrite most of this for 2.5.x -DaveM
112 */
113
114#include <linux/module.h>
115#include <linux/kernel.h>
116#include <linux/init.h>
117#include <linux/timer.h>
118#include <linux/netdevice.h>
Eric W. Biederman881d9662007-09-17 11:56:21 -0700119#include <net/net_namespace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
121#include <linux/if.h>
122#include <linux/if_arp.h>
123#include <linux/if_eql.h>
124
125#include <asm/uaccess.h>
126
127static int eql_open(struct net_device *dev);
128static int eql_close(struct net_device *dev);
129static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
130static int eql_slave_xmit(struct sk_buff *skb, struct net_device *dev);
131static struct net_device_stats *eql_get_stats(struct net_device *dev);
132
133#define eql_is_slave(dev) ((dev->flags & IFF_SLAVE) == IFF_SLAVE)
134#define eql_is_master(dev) ((dev->flags & IFF_MASTER) == IFF_MASTER)
135
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700136static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137
138static void eql_timer(unsigned long param)
139{
140 equalizer_t *eql = (equalizer_t *) param;
141 struct list_head *this, *tmp, *head;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400142
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 spin_lock_bh(&eql->queue.lock);
144 head = &eql->queue.all_slaves;
145 list_for_each_safe(this, tmp, head) {
146 slave_t *slave = list_entry(this, slave_t, list);
147
148 if ((slave->dev->flags & IFF_UP) == IFF_UP) {
149 slave->bytes_queued -= slave->priority_Bps;
150 if (slave->bytes_queued < 0)
151 slave->bytes_queued = 0;
152 } else {
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700153 eql_kill_one_slave(&eql->queue, slave);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 }
155
156 }
157 spin_unlock_bh(&eql->queue.lock);
158
159 eql->timer.expires = jiffies + EQL_DEFAULT_RESCHED_IVAL;
160 add_timer(&eql->timer);
161}
162
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400163static char version[] __initdata =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 "Equalizer2002: Simon Janes (simon@ncm.com) and David S. Miller (davem@redhat.com)\n";
165
166static void __init eql_setup(struct net_device *dev)
167{
168 equalizer_t *eql = netdev_priv(dev);
169
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 init_timer(&eql->timer);
171 eql->timer.data = (unsigned long) eql;
172 eql->timer.expires = jiffies + EQL_DEFAULT_RESCHED_IVAL;
173 eql->timer.function = eql_timer;
174
175 spin_lock_init(&eql->queue.lock);
176 INIT_LIST_HEAD(&eql->queue.all_slaves);
177 eql->queue.master_dev = dev;
178
179 dev->open = eql_open;
180 dev->stop = eql_close;
181 dev->do_ioctl = eql_ioctl;
182 dev->hard_start_xmit = eql_slave_xmit;
183 dev->get_stats = eql_get_stats;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 /*
186 * Now we undo some of the things that eth_setup does
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400187 * that we don't like
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 */
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400189
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 dev->mtu = EQL_DEFAULT_MTU; /* set to 576 in if_eql.h */
191 dev->flags = IFF_MASTER;
192
193 dev->type = ARPHRD_SLIP;
194 dev->tx_queue_len = 5; /* Hands them off fast */
195}
196
197static int eql_open(struct net_device *dev)
198{
199 equalizer_t *eql = netdev_priv(dev);
200
201 /* XXX We should force this off automatically for the user. */
202 printk(KERN_INFO "%s: remember to turn off Van-Jacobson compression on "
203 "your slave devices.\n", dev->name);
204
Eric Sesterhenn5d9428d2006-04-02 13:52:48 +0200205 BUG_ON(!list_empty(&eql->queue.all_slaves));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
207 eql->min_slaves = 1;
208 eql->max_slaves = EQL_DEFAULT_MAX_SLAVES; /* 4 usually... */
209
210 add_timer(&eql->timer);
211
212 return 0;
213}
214
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700215static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216{
217 list_del(&slave->list);
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700218 queue->num_slaves--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 slave->dev->flags &= ~IFF_SLAVE;
220 dev_put(slave->dev);
221 kfree(slave);
222}
223
224static void eql_kill_slave_queue(slave_queue_t *queue)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400225{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 struct list_head *head, *tmp, *this;
227
228 spin_lock_bh(&queue->lock);
229
230 head = &queue->all_slaves;
231 list_for_each_safe(this, tmp, head) {
232 slave_t *s = list_entry(this, slave_t, list);
233
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700234 eql_kill_one_slave(queue, s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 }
236
237 spin_unlock_bh(&queue->lock);
238}
239
240static int eql_close(struct net_device *dev)
241{
242 equalizer_t *eql = netdev_priv(dev);
243
244 /*
245 * The timer has to be stopped first before we start hacking away
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400246 * at the data structure it scans every so often...
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 */
248
249 del_timer_sync(&eql->timer);
250
251 eql_kill_slave_queue(&eql->queue);
252
253 return 0;
254}
255
256static int eql_enslave(struct net_device *dev, slaving_request_t __user *srq);
257static int eql_emancipate(struct net_device *dev, slaving_request_t __user *srq);
258
259static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
260static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
261
262static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mc);
263static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mc);
264
265static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400266{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 if (cmd != EQL_GETMASTRCFG && cmd != EQL_GETSLAVECFG &&
268 !capable(CAP_NET_ADMIN))
269 return -EPERM;
270
271 switch (cmd) {
272 case EQL_ENSLAVE:
273 return eql_enslave(dev, ifr->ifr_data);
274 case EQL_EMANCIPATE:
275 return eql_emancipate(dev, ifr->ifr_data);
276 case EQL_GETSLAVECFG:
277 return eql_g_slave_cfg(dev, ifr->ifr_data);
278 case EQL_SETSLAVECFG:
279 return eql_s_slave_cfg(dev, ifr->ifr_data);
280 case EQL_GETMASTRCFG:
281 return eql_g_master_cfg(dev, ifr->ifr_data);
282 case EQL_SETMASTRCFG:
283 return eql_s_master_cfg(dev, ifr->ifr_data);
284 default:
285 return -EOPNOTSUPP;
286 };
287}
288
289/* queue->lock must be held */
290static slave_t *__eql_schedule_slaves(slave_queue_t *queue)
291{
292 unsigned long best_load = ~0UL;
293 struct list_head *this, *tmp, *head;
294 slave_t *best_slave;
295
296 best_slave = NULL;
297
298 /* Make a pass to set the best slave. */
299 head = &queue->all_slaves;
300 list_for_each_safe(this, tmp, head) {
301 slave_t *slave = list_entry(this, slave_t, list);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400302 unsigned long slave_load, bytes_queued, priority_Bps;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303
304 /* Go through the slave list once, updating best_slave
305 * whenever a new best_load is found.
306 */
307 bytes_queued = slave->bytes_queued;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400308 priority_Bps = slave->priority_Bps;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 if ((slave->dev->flags & IFF_UP) == IFF_UP) {
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400310 slave_load = (~0UL - (~0UL / 2)) -
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 (priority_Bps) + bytes_queued * 8;
312
313 if (slave_load < best_load) {
314 best_load = slave_load;
315 best_slave = slave;
316 }
317 } else {
318 /* We found a dead slave, kill it. */
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700319 eql_kill_one_slave(queue, slave);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 }
321 }
322 return best_slave;
323}
324
325static int eql_slave_xmit(struct sk_buff *skb, struct net_device *dev)
326{
327 equalizer_t *eql = netdev_priv(dev);
328 slave_t *slave;
329
330 spin_lock(&eql->queue.lock);
331
332 slave = __eql_schedule_slaves(&eql->queue);
333 if (slave) {
334 struct net_device *slave_dev = slave->dev;
335
336 skb->dev = slave_dev;
337 skb->priority = 1;
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400338 slave->bytes_queued += skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 dev_queue_xmit(skb);
340 eql->stats.tx_packets++;
341 } else {
342 eql->stats.tx_dropped++;
343 dev_kfree_skb(skb);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400344 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345
346 spin_unlock(&eql->queue.lock);
347
348 return 0;
349}
350
351static struct net_device_stats * eql_get_stats(struct net_device *dev)
352{
353 equalizer_t *eql = netdev_priv(dev);
354 return &eql->stats;
355}
356
357/*
358 * Private ioctl functions
359 */
360
361/* queue->lock must be held */
362static slave_t *__eql_find_slave_dev(slave_queue_t *queue, struct net_device *dev)
363{
364 struct list_head *this, *head;
365
366 head = &queue->all_slaves;
367 list_for_each(this, head) {
368 slave_t *slave = list_entry(this, slave_t, list);
369
370 if (slave->dev == dev)
371 return slave;
372 }
373
374 return NULL;
375}
376
377static inline int eql_is_full(slave_queue_t *queue)
378{
379 equalizer_t *eql = netdev_priv(queue->master_dev);
380
381 if (queue->num_slaves >= eql->max_slaves)
382 return 1;
383 return 0;
384}
385
386/* queue->lock must be held */
387static int __eql_insert_slave(slave_queue_t *queue, slave_t *slave)
388{
389 if (!eql_is_full(queue)) {
390 slave_t *duplicate_slave = NULL;
391
392 duplicate_slave = __eql_find_slave_dev(queue, slave->dev);
Stephen Hemminger37d2e732007-08-24 22:37:49 -0700393 if (duplicate_slave)
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700394 eql_kill_one_slave(queue, duplicate_slave);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395
396 list_add(&slave->list, &queue->all_slaves);
397 queue->num_slaves++;
398 slave->dev->flags |= IFF_SLAVE;
399
400 return 0;
401 }
402
403 return -ENOSPC;
404}
405
406static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *srqp)
407{
408 struct net_device *slave_dev;
409 slaving_request_t srq;
410
411 if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
412 return -EFAULT;
413
Eric W. Biederman881d9662007-09-17 11:56:21 -0700414 slave_dev = dev_get_by_name(&init_net, srq.slave_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 if (slave_dev) {
416 if ((master_dev->flags & IFF_UP) == IFF_UP) {
417 /* slave is not a master & not already a slave: */
418 if (!eql_is_master(slave_dev) &&
419 !eql_is_slave(slave_dev)) {
420 slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
421 equalizer_t *eql = netdev_priv(master_dev);
422 int ret;
423
424 if (!s) {
425 dev_put(slave_dev);
426 return -ENOMEM;
427 }
428
429 memset(s, 0, sizeof(*s));
430 s->dev = slave_dev;
431 s->priority = srq.priority;
432 s->priority_bps = srq.priority;
433 s->priority_Bps = srq.priority / 8;
434
435 spin_lock_bh(&eql->queue.lock);
436 ret = __eql_insert_slave(&eql->queue, s);
437 if (ret) {
438 dev_put(slave_dev);
439 kfree(s);
440 }
441 spin_unlock_bh(&eql->queue.lock);
442
443 return ret;
444 }
445 }
446 dev_put(slave_dev);
447 }
448
449 return -EINVAL;
450}
451
452static int eql_emancipate(struct net_device *master_dev, slaving_request_t __user *srqp)
453{
454 equalizer_t *eql = netdev_priv(master_dev);
455 struct net_device *slave_dev;
456 slaving_request_t srq;
457 int ret;
458
459 if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
460 return -EFAULT;
461
Eric W. Biederman881d9662007-09-17 11:56:21 -0700462 slave_dev = dev_get_by_name(&init_net, srq.slave_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 ret = -EINVAL;
464 if (slave_dev) {
465 spin_lock_bh(&eql->queue.lock);
466
467 if (eql_is_slave(slave_dev)) {
468 slave_t *slave = __eql_find_slave_dev(&eql->queue,
469 slave_dev);
470
471 if (slave) {
Loic Le Loarer14a59e12005-07-21 14:16:54 -0700472 eql_kill_one_slave(&eql->queue, slave);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 ret = 0;
474 }
475 }
476 dev_put(slave_dev);
477
478 spin_unlock_bh(&eql->queue.lock);
479 }
480
481 return ret;
482}
483
484static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
485{
486 equalizer_t *eql = netdev_priv(dev);
487 slave_t *slave;
488 struct net_device *slave_dev;
489 slave_config_t sc;
490 int ret;
491
492 if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
493 return -EFAULT;
494
Eric W. Biederman881d9662007-09-17 11:56:21 -0700495 slave_dev = dev_get_by_name(&init_net, sc.slave_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 if (!slave_dev)
497 return -ENODEV;
498
499 ret = -EINVAL;
500
501 spin_lock_bh(&eql->queue.lock);
502 if (eql_is_slave(slave_dev)) {
503 slave = __eql_find_slave_dev(&eql->queue, slave_dev);
504 if (slave) {
505 sc.priority = slave->priority;
506 ret = 0;
507 }
508 }
509 spin_unlock_bh(&eql->queue.lock);
510
511 dev_put(slave_dev);
512
513 if (!ret && copy_to_user(scp, &sc, sizeof (slave_config_t)))
514 ret = -EFAULT;
515
516 return ret;
517}
518
519static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
520{
521 slave_t *slave;
522 equalizer_t *eql;
523 struct net_device *slave_dev;
524 slave_config_t sc;
525 int ret;
526
527 if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
528 return -EFAULT;
529
Eric W. Biederman881d9662007-09-17 11:56:21 -0700530 slave_dev = dev_get_by_name(&init_net, sc.slave_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 if (!slave_dev)
532 return -ENODEV;
533
534 ret = -EINVAL;
535
536 eql = netdev_priv(dev);
537 spin_lock_bh(&eql->queue.lock);
538 if (eql_is_slave(slave_dev)) {
539 slave = __eql_find_slave_dev(&eql->queue, slave_dev);
540 if (slave) {
541 slave->priority = sc.priority;
542 slave->priority_bps = sc.priority;
543 slave->priority_Bps = sc.priority / 8;
544 ret = 0;
545 }
546 }
547 spin_unlock_bh(&eql->queue.lock);
548
549 return ret;
550}
551
552static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mcp)
553{
554 equalizer_t *eql;
555 master_config_t mc;
556
557 if (eql_is_master(dev)) {
558 eql = netdev_priv(dev);
559 mc.max_slaves = eql->max_slaves;
560 mc.min_slaves = eql->min_slaves;
561 if (copy_to_user(mcp, &mc, sizeof (master_config_t)))
562 return -EFAULT;
563 return 0;
564 }
565 return -EINVAL;
566}
567
568static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mcp)
569{
570 equalizer_t *eql;
571 master_config_t mc;
572
573 if (copy_from_user(&mc, mcp, sizeof (master_config_t)))
574 return -EFAULT;
575
576 if (eql_is_master(dev)) {
577 eql = netdev_priv(dev);
578 eql->max_slaves = mc.max_slaves;
579 eql->min_slaves = mc.min_slaves;
580 return 0;
581 }
582 return -EINVAL;
583}
584
585static struct net_device *dev_eql;
586
587static int __init eql_init_module(void)
588{
589 int err;
590
591 printk(version);
592
593 dev_eql = alloc_netdev(sizeof(equalizer_t), "eql", eql_setup);
594 if (!dev_eql)
595 return -ENOMEM;
596
597 err = register_netdev(dev_eql);
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400598 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 free_netdev(dev_eql);
600 return err;
601}
602
603static void __exit eql_cleanup_module(void)
604{
605 unregister_netdev(dev_eql);
606 free_netdev(dev_eql);
607}
608
609module_init(eql_init_module);
610module_exit(eql_cleanup_module);
611MODULE_LICENSE("GPL");