[NET]: Nuke SET_MODULE_OWNER macro.
[linux-2.6.git] / drivers / net / eql.c
1 /*
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.
11  *
12  * 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:
26  *   The Alan Cox and Mike McLagan plot to get someone else to do the code,
27  *   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>
119 #include <net/net_namespace.h>
120
121 #include <linux/if.h>
122 #include <linux/if_arp.h>
123 #include <linux/if_eql.h>
124
125 #include <asm/uaccess.h>
126
127 static int eql_open(struct net_device *dev);
128 static int eql_close(struct net_device *dev);
129 static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
130 static int eql_slave_xmit(struct sk_buff *skb, struct net_device *dev);
131 static 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
136 static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave);
137
138 static void eql_timer(unsigned long param)
139 {
140         equalizer_t *eql = (equalizer_t *) param;
141         struct list_head *this, *tmp, *head;
142
143         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 {
153                         eql_kill_one_slave(&eql->queue, slave);
154                 }
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
163 static char version[] __initdata =
164         "Equalizer2002: Simon Janes (simon@ncm.com) and David S. Miller (davem@redhat.com)\n";
165
166 static void __init eql_setup(struct net_device *dev)
167 {
168         equalizer_t *eql = netdev_priv(dev);
169
170         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;
184
185         /*
186          *      Now we undo some of the things that eth_setup does
187          *      that we don't like
188          */
189
190         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
197 static 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
205         BUG_ON(!list_empty(&eql->queue.all_slaves));
206
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
215 static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave)
216 {
217         list_del(&slave->list);
218         queue->num_slaves--;
219         slave->dev->flags &= ~IFF_SLAVE;
220         dev_put(slave->dev);
221         kfree(slave);
222 }
223
224 static void eql_kill_slave_queue(slave_queue_t *queue)
225 {
226         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
234                 eql_kill_one_slave(queue, s);
235         }
236
237         spin_unlock_bh(&queue->lock);
238 }
239
240 static 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
246          *      at the data structure it scans every so often...
247          */
248
249         del_timer_sync(&eql->timer);
250
251         eql_kill_slave_queue(&eql->queue);
252
253         return 0;
254 }
255
256 static int eql_enslave(struct net_device *dev,  slaving_request_t __user *srq);
257 static int eql_emancipate(struct net_device *dev, slaving_request_t __user *srq);
258
259 static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
260 static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
261
262 static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mc);
263 static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mc);
264
265 static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
266 {
267         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 */
290 static 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);
302                 unsigned long slave_load, bytes_queued, priority_Bps;
303
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;
308                 priority_Bps = slave->priority_Bps;
309                 if ((slave->dev->flags & IFF_UP) == IFF_UP) {
310                         slave_load = (~0UL - (~0UL / 2)) -
311                                 (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. */
319                         eql_kill_one_slave(queue, slave);
320                 }
321         }
322         return best_slave;
323 }
324
325 static 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;
338                 slave->bytes_queued += skb->len;
339                 dev_queue_xmit(skb);
340                 eql->stats.tx_packets++;
341         } else {
342                 eql->stats.tx_dropped++;
343                 dev_kfree_skb(skb);
344         }
345
346         spin_unlock(&eql->queue.lock);
347
348         return 0;
349 }
350
351 static 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 */
362 static 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
377 static 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 */
387 static 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);
393                 if (duplicate_slave)
394                         eql_kill_one_slave(queue, duplicate_slave);
395
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
406 static 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
414         slave_dev  = dev_get_by_name(&init_net, srq.slave_name);
415         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
452 static 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
462         slave_dev = dev_get_by_name(&init_net, srq.slave_name);
463         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) {
472                                 eql_kill_one_slave(&eql->queue, slave);
473                                 ret = 0;
474                         }
475                 }
476                 dev_put(slave_dev);
477
478                 spin_unlock_bh(&eql->queue.lock);
479         }
480
481         return ret;
482 }
483
484 static 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
495         slave_dev = dev_get_by_name(&init_net, sc.slave_name);
496         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
519 static 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
530         slave_dev = dev_get_by_name(&init_net, sc.slave_name);
531         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
552 static 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
568 static 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
585 static struct net_device *dev_eql;
586
587 static 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);
598         if (err)
599                 free_netdev(dev_eql);
600         return err;
601 }
602
603 static void __exit eql_cleanup_module(void)
604 {
605         unregister_netdev(dev_eql);
606         free_netdev(dev_eql);
607 }
608
609 module_init(eql_init_module);
610 module_exit(eql_cleanup_module);
611 MODULE_LICENSE("GPL");