macvlan: validate flags
[linux-3.10.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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
115
116 #include <linux/capability.h>
117 #include <linux/module.h>
118 #include <linux/kernel.h>
119 #include <linux/init.h>
120 #include <linux/slab.h>
121 #include <linux/timer.h>
122 #include <linux/netdevice.h>
123 #include <net/net_namespace.h>
124
125 #include <linux/if.h>
126 #include <linux/if_arp.h>
127 #include <linux/if_eql.h>
128 #include <linux/pkt_sched.h>
129
130 #include <asm/uaccess.h>
131
132 static int eql_open(struct net_device *dev);
133 static int eql_close(struct net_device *dev);
134 static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
135 static netdev_tx_t eql_slave_xmit(struct sk_buff *skb, struct net_device *dev);
136
137 #define eql_is_slave(dev)       ((dev->flags & IFF_SLAVE) == IFF_SLAVE)
138 #define eql_is_master(dev)      ((dev->flags & IFF_MASTER) == IFF_MASTER)
139
140 static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave);
141
142 static void eql_timer(unsigned long param)
143 {
144         equalizer_t *eql = (equalizer_t *) param;
145         struct list_head *this, *tmp, *head;
146
147         spin_lock(&eql->queue.lock);
148         head = &eql->queue.all_slaves;
149         list_for_each_safe(this, tmp, head) {
150                 slave_t *slave = list_entry(this, slave_t, list);
151
152                 if ((slave->dev->flags & IFF_UP) == IFF_UP) {
153                         slave->bytes_queued -= slave->priority_Bps;
154                         if (slave->bytes_queued < 0)
155                                 slave->bytes_queued = 0;
156                 } else {
157                         eql_kill_one_slave(&eql->queue, slave);
158                 }
159
160         }
161         spin_unlock(&eql->queue.lock);
162
163         eql->timer.expires = jiffies + EQL_DEFAULT_RESCHED_IVAL;
164         add_timer(&eql->timer);
165 }
166
167 static const char version[] __initconst =
168         "Equalizer2002: Simon Janes (simon@ncm.com) and David S. Miller (davem@redhat.com)";
169
170 static const struct net_device_ops eql_netdev_ops = {
171         .ndo_open       = eql_open,
172         .ndo_stop       = eql_close,
173         .ndo_do_ioctl   = eql_ioctl,
174         .ndo_start_xmit = eql_slave_xmit,
175 };
176
177 static void __init eql_setup(struct net_device *dev)
178 {
179         equalizer_t *eql = netdev_priv(dev);
180
181         init_timer(&eql->timer);
182         eql->timer.data         = (unsigned long) eql;
183         eql->timer.expires      = jiffies + EQL_DEFAULT_RESCHED_IVAL;
184         eql->timer.function     = eql_timer;
185
186         spin_lock_init(&eql->queue.lock);
187         INIT_LIST_HEAD(&eql->queue.all_slaves);
188         eql->queue.master_dev   = dev;
189
190         dev->netdev_ops         = &eql_netdev_ops;
191
192         /*
193          *      Now we undo some of the things that eth_setup does
194          *      that we don't like
195          */
196
197         dev->mtu                = EQL_DEFAULT_MTU;      /* set to 576 in if_eql.h */
198         dev->flags              = IFF_MASTER;
199
200         dev->type               = ARPHRD_SLIP;
201         dev->tx_queue_len       = 5;            /* Hands them off fast */
202         dev->priv_flags        &= ~IFF_XMIT_DST_RELEASE;
203 }
204
205 static int eql_open(struct net_device *dev)
206 {
207         equalizer_t *eql = netdev_priv(dev);
208
209         /* XXX We should force this off automatically for the user. */
210         netdev_info(dev,
211                     "remember to turn off Van-Jacobson compression on your slave devices\n");
212
213         BUG_ON(!list_empty(&eql->queue.all_slaves));
214
215         eql->min_slaves = 1;
216         eql->max_slaves = EQL_DEFAULT_MAX_SLAVES; /* 4 usually... */
217
218         add_timer(&eql->timer);
219
220         return 0;
221 }
222
223 static void eql_kill_one_slave(slave_queue_t *queue, slave_t *slave)
224 {
225         list_del(&slave->list);
226         queue->num_slaves--;
227         slave->dev->flags &= ~IFF_SLAVE;
228         dev_put(slave->dev);
229         kfree(slave);
230 }
231
232 static void eql_kill_slave_queue(slave_queue_t *queue)
233 {
234         struct list_head *head, *tmp, *this;
235
236         spin_lock_bh(&queue->lock);
237
238         head = &queue->all_slaves;
239         list_for_each_safe(this, tmp, head) {
240                 slave_t *s = list_entry(this, slave_t, list);
241
242                 eql_kill_one_slave(queue, s);
243         }
244
245         spin_unlock_bh(&queue->lock);
246 }
247
248 static int eql_close(struct net_device *dev)
249 {
250         equalizer_t *eql = netdev_priv(dev);
251
252         /*
253          *      The timer has to be stopped first before we start hacking away
254          *      at the data structure it scans every so often...
255          */
256
257         del_timer_sync(&eql->timer);
258
259         eql_kill_slave_queue(&eql->queue);
260
261         return 0;
262 }
263
264 static int eql_enslave(struct net_device *dev,  slaving_request_t __user *srq);
265 static int eql_emancipate(struct net_device *dev, slaving_request_t __user *srq);
266
267 static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
268 static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *sc);
269
270 static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mc);
271 static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mc);
272
273 static int eql_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
274 {
275         if (cmd != EQL_GETMASTRCFG && cmd != EQL_GETSLAVECFG &&
276             !capable(CAP_NET_ADMIN))
277                 return -EPERM;
278
279         switch (cmd) {
280                 case EQL_ENSLAVE:
281                         return eql_enslave(dev, ifr->ifr_data);
282                 case EQL_EMANCIPATE:
283                         return eql_emancipate(dev, ifr->ifr_data);
284                 case EQL_GETSLAVECFG:
285                         return eql_g_slave_cfg(dev, ifr->ifr_data);
286                 case EQL_SETSLAVECFG:
287                         return eql_s_slave_cfg(dev, ifr->ifr_data);
288                 case EQL_GETMASTRCFG:
289                         return eql_g_master_cfg(dev, ifr->ifr_data);
290                 case EQL_SETMASTRCFG:
291                         return eql_s_master_cfg(dev, ifr->ifr_data);
292                 default:
293                         return -EOPNOTSUPP;
294         }
295 }
296
297 /* queue->lock must be held */
298 static slave_t *__eql_schedule_slaves(slave_queue_t *queue)
299 {
300         unsigned long best_load = ~0UL;
301         struct list_head *this, *tmp, *head;
302         slave_t *best_slave;
303
304         best_slave = NULL;
305
306         /* Make a pass to set the best slave. */
307         head = &queue->all_slaves;
308         list_for_each_safe(this, tmp, head) {
309                 slave_t *slave = list_entry(this, slave_t, list);
310                 unsigned long slave_load, bytes_queued, priority_Bps;
311
312                 /* Go through the slave list once, updating best_slave
313                  * whenever a new best_load is found.
314                  */
315                 bytes_queued = slave->bytes_queued;
316                 priority_Bps = slave->priority_Bps;
317                 if ((slave->dev->flags & IFF_UP) == IFF_UP) {
318                         slave_load = (~0UL - (~0UL / 2)) -
319                                 (priority_Bps) + bytes_queued * 8;
320
321                         if (slave_load < best_load) {
322                                 best_load = slave_load;
323                                 best_slave = slave;
324                         }
325                 } else {
326                         /* We found a dead slave, kill it. */
327                         eql_kill_one_slave(queue, slave);
328                 }
329         }
330         return best_slave;
331 }
332
333 static netdev_tx_t eql_slave_xmit(struct sk_buff *skb, struct net_device *dev)
334 {
335         equalizer_t *eql = netdev_priv(dev);
336         slave_t *slave;
337
338         spin_lock(&eql->queue.lock);
339
340         slave = __eql_schedule_slaves(&eql->queue);
341         if (slave) {
342                 struct net_device *slave_dev = slave->dev;
343
344                 skb->dev = slave_dev;
345                 skb->priority = TC_PRIO_FILLER;
346                 slave->bytes_queued += skb->len;
347                 dev_queue_xmit(skb);
348                 dev->stats.tx_packets++;
349         } else {
350                 dev->stats.tx_dropped++;
351                 dev_kfree_skb(skb);
352         }
353
354         spin_unlock(&eql->queue.lock);
355
356         return NETDEV_TX_OK;
357 }
358
359 /*
360  *      Private ioctl functions
361  */
362
363 /* queue->lock must be held */
364 static slave_t *__eql_find_slave_dev(slave_queue_t *queue, struct net_device *dev)
365 {
366         struct list_head *this, *head;
367
368         head = &queue->all_slaves;
369         list_for_each(this, head) {
370                 slave_t *slave = list_entry(this, slave_t, list);
371
372                 if (slave->dev == dev)
373                         return slave;
374         }
375
376         return NULL;
377 }
378
379 static inline int eql_is_full(slave_queue_t *queue)
380 {
381         equalizer_t *eql = netdev_priv(queue->master_dev);
382
383         if (queue->num_slaves >= eql->max_slaves)
384                 return 1;
385         return 0;
386 }
387
388 /* queue->lock must be held */
389 static int __eql_insert_slave(slave_queue_t *queue, slave_t *slave)
390 {
391         if (!eql_is_full(queue)) {
392                 slave_t *duplicate_slave = NULL;
393
394                 duplicate_slave = __eql_find_slave_dev(queue, slave->dev);
395                 if (duplicate_slave)
396                         eql_kill_one_slave(queue, duplicate_slave);
397
398                 list_add(&slave->list, &queue->all_slaves);
399                 queue->num_slaves++;
400                 slave->dev->flags |= IFF_SLAVE;
401
402                 return 0;
403         }
404
405         return -ENOSPC;
406 }
407
408 static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *srqp)
409 {
410         struct net_device *slave_dev;
411         slaving_request_t srq;
412
413         if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
414                 return -EFAULT;
415
416         slave_dev  = dev_get_by_name(&init_net, srq.slave_name);
417         if (slave_dev) {
418                 if ((master_dev->flags & IFF_UP) == IFF_UP) {
419                         /* slave is not a master & not already a slave: */
420                         if (!eql_is_master(slave_dev) &&
421                             !eql_is_slave(slave_dev)) {
422                                 slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
423                                 equalizer_t *eql = netdev_priv(master_dev);
424                                 int ret;
425
426                                 if (!s) {
427                                         dev_put(slave_dev);
428                                         return -ENOMEM;
429                                 }
430
431                                 memset(s, 0, sizeof(*s));
432                                 s->dev = slave_dev;
433                                 s->priority = srq.priority;
434                                 s->priority_bps = srq.priority;
435                                 s->priority_Bps = srq.priority / 8;
436
437                                 spin_lock_bh(&eql->queue.lock);
438                                 ret = __eql_insert_slave(&eql->queue, s);
439                                 if (ret) {
440                                         dev_put(slave_dev);
441                                         kfree(s);
442                                 }
443                                 spin_unlock_bh(&eql->queue.lock);
444
445                                 return ret;
446                         }
447                 }
448                 dev_put(slave_dev);
449         }
450
451         return -EINVAL;
452 }
453
454 static int eql_emancipate(struct net_device *master_dev, slaving_request_t __user *srqp)
455 {
456         equalizer_t *eql = netdev_priv(master_dev);
457         struct net_device *slave_dev;
458         slaving_request_t srq;
459         int ret;
460
461         if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
462                 return -EFAULT;
463
464         slave_dev = dev_get_by_name(&init_net, srq.slave_name);
465         ret = -EINVAL;
466         if (slave_dev) {
467                 spin_lock_bh(&eql->queue.lock);
468
469                 if (eql_is_slave(slave_dev)) {
470                         slave_t *slave = __eql_find_slave_dev(&eql->queue,
471                                                               slave_dev);
472
473                         if (slave) {
474                                 eql_kill_one_slave(&eql->queue, slave);
475                                 ret = 0;
476                         }
477                 }
478                 dev_put(slave_dev);
479
480                 spin_unlock_bh(&eql->queue.lock);
481         }
482
483         return ret;
484 }
485
486 static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
487 {
488         equalizer_t *eql = netdev_priv(dev);
489         slave_t *slave;
490         struct net_device *slave_dev;
491         slave_config_t sc;
492         int ret;
493
494         if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
495                 return -EFAULT;
496
497         slave_dev = dev_get_by_name(&init_net, sc.slave_name);
498         if (!slave_dev)
499                 return -ENODEV;
500
501         ret = -EINVAL;
502
503         spin_lock_bh(&eql->queue.lock);
504         if (eql_is_slave(slave_dev)) {
505                 slave = __eql_find_slave_dev(&eql->queue, slave_dev);
506                 if (slave) {
507                         sc.priority = slave->priority;
508                         ret = 0;
509                 }
510         }
511         spin_unlock_bh(&eql->queue.lock);
512
513         dev_put(slave_dev);
514
515         if (!ret && copy_to_user(scp, &sc, sizeof (slave_config_t)))
516                 ret = -EFAULT;
517
518         return ret;
519 }
520
521 static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
522 {
523         slave_t *slave;
524         equalizer_t *eql;
525         struct net_device *slave_dev;
526         slave_config_t sc;
527         int ret;
528
529         if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
530                 return -EFAULT;
531
532         slave_dev = dev_get_by_name(&init_net, sc.slave_name);
533         if (!slave_dev)
534                 return -ENODEV;
535
536         ret = -EINVAL;
537
538         eql = netdev_priv(dev);
539         spin_lock_bh(&eql->queue.lock);
540         if (eql_is_slave(slave_dev)) {
541                 slave = __eql_find_slave_dev(&eql->queue, slave_dev);
542                 if (slave) {
543                         slave->priority = sc.priority;
544                         slave->priority_bps = sc.priority;
545                         slave->priority_Bps = sc.priority / 8;
546                         ret = 0;
547                 }
548         }
549         spin_unlock_bh(&eql->queue.lock);
550
551         dev_put(slave_dev);
552
553         return ret;
554 }
555
556 static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mcp)
557 {
558         equalizer_t *eql;
559         master_config_t mc;
560
561         memset(&mc, 0, sizeof(master_config_t));
562
563         if (eql_is_master(dev)) {
564                 eql = netdev_priv(dev);
565                 mc.max_slaves = eql->max_slaves;
566                 mc.min_slaves = eql->min_slaves;
567                 if (copy_to_user(mcp, &mc, sizeof (master_config_t)))
568                         return -EFAULT;
569                 return 0;
570         }
571         return -EINVAL;
572 }
573
574 static int eql_s_master_cfg(struct net_device *dev, master_config_t __user *mcp)
575 {
576         equalizer_t *eql;
577         master_config_t mc;
578
579         if (copy_from_user(&mc, mcp, sizeof (master_config_t)))
580                 return -EFAULT;
581
582         if (eql_is_master(dev)) {
583                 eql = netdev_priv(dev);
584                 eql->max_slaves = mc.max_slaves;
585                 eql->min_slaves = mc.min_slaves;
586                 return 0;
587         }
588         return -EINVAL;
589 }
590
591 static struct net_device *dev_eql;
592
593 static int __init eql_init_module(void)
594 {
595         int err;
596
597         pr_info("%s\n", version);
598
599         dev_eql = alloc_netdev(sizeof(equalizer_t), "eql", eql_setup);
600         if (!dev_eql)
601                 return -ENOMEM;
602
603         err = register_netdev(dev_eql);
604         if (err)
605                 free_netdev(dev_eql);
606         return err;
607 }
608
609 static void __exit eql_cleanup_module(void)
610 {
611         unregister_netdev(dev_eql);
612         free_netdev(dev_eql);
613 }
614
615 module_init(eql_init_module);
616 module_exit(eql_cleanup_module);
617 MODULE_LICENSE("GPL");