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Commit | Line | Data |
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1da177e4 LT |
1 | /* net/sched/sch_teql.c "True" (or "trivial") link equalizer. |
2 | * | |
3 | * This program is free software; you can redistribute it and/or | |
4 | * modify it under the terms of the GNU General Public License | |
5 | * as published by the Free Software Foundation; either version | |
6 | * 2 of the License, or (at your option) any later version. | |
7 | * | |
8 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
9 | */ | |
10 | ||
11 | #include <linux/module.h> | |
1da177e4 LT |
12 | #include <linux/types.h> |
13 | #include <linux/kernel.h> | |
5a0e3ad6 | 14 | #include <linux/slab.h> |
1da177e4 | 15 | #include <linux/string.h> |
1da177e4 | 16 | #include <linux/errno.h> |
14c85021 | 17 | #include <linux/if_arp.h> |
1da177e4 | 18 | #include <linux/netdevice.h> |
1da177e4 | 19 | #include <linux/init.h> |
1da177e4 LT |
20 | #include <linux/skbuff.h> |
21 | #include <linux/moduleparam.h> | |
0ba48053 PM |
22 | #include <net/dst.h> |
23 | #include <net/neighbour.h> | |
1da177e4 LT |
24 | #include <net/pkt_sched.h> |
25 | ||
26 | /* | |
27 | How to setup it. | |
28 | ---------------- | |
29 | ||
30 | After loading this module you will find a new device teqlN | |
31 | and new qdisc with the same name. To join a slave to the equalizer | |
32 | you should just set this qdisc on a device f.e. | |
33 | ||
34 | # tc qdisc add dev eth0 root teql0 | |
35 | # tc qdisc add dev eth1 root teql0 | |
36 | ||
37 | That's all. Full PnP 8) | |
38 | ||
39 | Applicability. | |
40 | -------------- | |
41 | ||
42 | 1. Slave devices MUST be active devices, i.e., they must raise the tbusy | |
43 | signal and generate EOI events. If you want to equalize virtual devices | |
44 | like tunnels, use a normal eql device. | |
45 | 2. This device puts no limitations on physical slave characteristics | |
46 | f.e. it will equalize 9600baud line and 100Mb ethernet perfectly :-) | |
47 | Certainly, large difference in link speeds will make the resulting | |
48 | eqalized link unusable, because of huge packet reordering. | |
49 | I estimate an upper useful difference as ~10 times. | |
50 | 3. If the slave requires address resolution, only protocols using | |
51 | neighbour cache (IPv4/IPv6) will work over the equalized link. | |
52 | Other protocols are still allowed to use the slave device directly, | |
53 | which will not break load balancing, though native slave | |
54 | traffic will have the highest priority. */ | |
55 | ||
cc7ec456 | 56 | struct teql_master { |
1da177e4 LT |
57 | struct Qdisc_ops qops; |
58 | struct net_device *dev; | |
59 | struct Qdisc *slaves; | |
60 | struct list_head master_list; | |
1ac9ad13 ED |
61 | unsigned long tx_bytes; |
62 | unsigned long tx_packets; | |
63 | unsigned long tx_errors; | |
64 | unsigned long tx_dropped; | |
1da177e4 LT |
65 | }; |
66 | ||
cc7ec456 | 67 | struct teql_sched_data { |
1da177e4 LT |
68 | struct Qdisc *next; |
69 | struct teql_master *m; | |
1da177e4 LT |
70 | struct sk_buff_head q; |
71 | }; | |
72 | ||
cc7ec456 | 73 | #define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next) |
1da177e4 | 74 | |
cc7ec456 | 75 | #define FMASK (IFF_BROADCAST | IFF_POINTOPOINT) |
1da177e4 LT |
76 | |
77 | /* "teql*" qdisc routines */ | |
78 | ||
79 | static int | |
cc7ec456 | 80 | teql_enqueue(struct sk_buff *skb, struct Qdisc *sch) |
1da177e4 | 81 | { |
5ce2d488 | 82 | struct net_device *dev = qdisc_dev(sch); |
1da177e4 LT |
83 | struct teql_sched_data *q = qdisc_priv(sch); |
84 | ||
4cd8c9e8 KK |
85 | if (q->q.qlen < dev->tx_queue_len) { |
86 | __skb_queue_tail(&q->q, skb); | |
9871e50e | 87 | return NET_XMIT_SUCCESS; |
1da177e4 LT |
88 | } |
89 | ||
17045755 | 90 | return qdisc_drop(skb, sch); |
1da177e4 LT |
91 | } |
92 | ||
1da177e4 | 93 | static struct sk_buff * |
cc7ec456 | 94 | teql_dequeue(struct Qdisc *sch) |
1da177e4 LT |
95 | { |
96 | struct teql_sched_data *dat = qdisc_priv(sch); | |
b0e1e646 | 97 | struct netdev_queue *dat_queue; |
1da177e4 LT |
98 | struct sk_buff *skb; |
99 | ||
100 | skb = __skb_dequeue(&dat->q); | |
e8a0464c | 101 | dat_queue = netdev_get_tx_queue(dat->m->dev, 0); |
1da177e4 | 102 | if (skb == NULL) { |
b0e1e646 | 103 | struct net_device *m = qdisc_dev(dat_queue->qdisc); |
1da177e4 LT |
104 | if (m) { |
105 | dat->m->slaves = sch; | |
106 | netif_wake_queue(m); | |
107 | } | |
9190b3b3 ED |
108 | } else { |
109 | qdisc_bstats_update(sch, skb); | |
1da177e4 | 110 | } |
b0e1e646 | 111 | sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen; |
1da177e4 LT |
112 | return skb; |
113 | } | |
114 | ||
8e3af978 | 115 | static struct sk_buff * |
cc7ec456 | 116 | teql_peek(struct Qdisc *sch) |
8e3af978 JP |
117 | { |
118 | /* teql is meant to be used as root qdisc */ | |
119 | return NULL; | |
120 | } | |
121 | ||
cc7ec456 | 122 | static inline void |
1da177e4 LT |
123 | teql_neigh_release(struct neighbour *n) |
124 | { | |
125 | if (n) | |
126 | neigh_release(n); | |
127 | } | |
128 | ||
129 | static void | |
cc7ec456 | 130 | teql_reset(struct Qdisc *sch) |
1da177e4 LT |
131 | { |
132 | struct teql_sched_data *dat = qdisc_priv(sch); | |
133 | ||
134 | skb_queue_purge(&dat->q); | |
135 | sch->q.qlen = 0; | |
1da177e4 LT |
136 | } |
137 | ||
138 | static void | |
cc7ec456 | 139 | teql_destroy(struct Qdisc *sch) |
1da177e4 LT |
140 | { |
141 | struct Qdisc *q, *prev; | |
142 | struct teql_sched_data *dat = qdisc_priv(sch); | |
143 | struct teql_master *master = dat->m; | |
144 | ||
cc7ec456 ED |
145 | prev = master->slaves; |
146 | if (prev) { | |
1da177e4 LT |
147 | do { |
148 | q = NEXT_SLAVE(prev); | |
149 | if (q == sch) { | |
150 | NEXT_SLAVE(prev) = NEXT_SLAVE(q); | |
151 | if (q == master->slaves) { | |
152 | master->slaves = NEXT_SLAVE(q); | |
153 | if (q == master->slaves) { | |
e8a0464c | 154 | struct netdev_queue *txq; |
83874000 | 155 | spinlock_t *root_lock; |
e8a0464c DM |
156 | |
157 | txq = netdev_get_tx_queue(master->dev, 0); | |
1da177e4 | 158 | master->slaves = NULL; |
83874000 | 159 | |
102396ae | 160 | root_lock = qdisc_root_sleeping_lock(txq->qdisc); |
83874000 | 161 | spin_lock_bh(root_lock); |
e8a0464c | 162 | qdisc_reset(txq->qdisc); |
83874000 | 163 | spin_unlock_bh(root_lock); |
1da177e4 LT |
164 | } |
165 | } | |
166 | skb_queue_purge(&dat->q); | |
1da177e4 LT |
167 | break; |
168 | } | |
10297b99 | 169 | |
1da177e4 LT |
170 | } while ((prev = q) != master->slaves); |
171 | } | |
172 | } | |
173 | ||
1e90474c | 174 | static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt) |
1da177e4 | 175 | { |
5ce2d488 | 176 | struct net_device *dev = qdisc_dev(sch); |
cc7ec456 | 177 | struct teql_master *m = (struct teql_master *)sch->ops; |
1da177e4 LT |
178 | struct teql_sched_data *q = qdisc_priv(sch); |
179 | ||
180 | if (dev->hard_header_len > m->dev->hard_header_len) | |
181 | return -EINVAL; | |
182 | ||
183 | if (m->dev == dev) | |
184 | return -ELOOP; | |
185 | ||
186 | q->m = m; | |
187 | ||
188 | skb_queue_head_init(&q->q); | |
189 | ||
190 | if (m->slaves) { | |
191 | if (m->dev->flags & IFF_UP) { | |
f64f9e71 JP |
192 | if ((m->dev->flags & IFF_POINTOPOINT && |
193 | !(dev->flags & IFF_POINTOPOINT)) || | |
194 | (m->dev->flags & IFF_BROADCAST && | |
195 | !(dev->flags & IFF_BROADCAST)) || | |
196 | (m->dev->flags & IFF_MULTICAST && | |
197 | !(dev->flags & IFF_MULTICAST)) || | |
198 | dev->mtu < m->dev->mtu) | |
1da177e4 LT |
199 | return -EINVAL; |
200 | } else { | |
201 | if (!(dev->flags&IFF_POINTOPOINT)) | |
202 | m->dev->flags &= ~IFF_POINTOPOINT; | |
203 | if (!(dev->flags&IFF_BROADCAST)) | |
204 | m->dev->flags &= ~IFF_BROADCAST; | |
205 | if (!(dev->flags&IFF_MULTICAST)) | |
206 | m->dev->flags &= ~IFF_MULTICAST; | |
207 | if (dev->mtu < m->dev->mtu) | |
208 | m->dev->mtu = dev->mtu; | |
209 | } | |
210 | q->next = NEXT_SLAVE(m->slaves); | |
211 | NEXT_SLAVE(m->slaves) = sch; | |
212 | } else { | |
213 | q->next = sch; | |
214 | m->slaves = sch; | |
215 | m->dev->mtu = dev->mtu; | |
216 | m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK); | |
217 | } | |
218 | return 0; | |
219 | } | |
220 | ||
1da177e4 LT |
221 | |
222 | static int | |
f7e57044 ED |
223 | __teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, |
224 | struct net_device *dev, struct netdev_queue *txq, | |
dbedbe6d | 225 | struct dst_entry *dst) |
1da177e4 | 226 | { |
dbedbe6d DM |
227 | struct neighbour *n; |
228 | int err = 0; | |
1da177e4 | 229 | |
dbedbe6d DM |
230 | n = dst_neigh_lookup_skb(dst, skb); |
231 | if (!n) | |
232 | return -ENOENT; | |
233 | ||
234 | if (dst->dev != dev) { | |
235 | struct neighbour *mn; | |
236 | ||
237 | mn = __neigh_lookup_errno(n->tbl, n->primary_key, dev); | |
238 | neigh_release(n); | |
239 | if (IS_ERR(mn)) | |
240 | return PTR_ERR(mn); | |
241 | n = mn; | |
1da177e4 | 242 | } |
dbedbe6d | 243 | |
1da177e4 LT |
244 | if (neigh_event_send(n, skb_res) == 0) { |
245 | int err; | |
0ed8ddf4 | 246 | char haddr[MAX_ADDR_LEN]; |
0c4e8581 | 247 | |
0ed8ddf4 ED |
248 | neigh_ha_snapshot(haddr, n, dev); |
249 | err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr, | |
250 | NULL, skb->len); | |
0c4e8581 | 251 | |
dbedbe6d DM |
252 | if (err < 0) |
253 | err = -EINVAL; | |
254 | } else { | |
255 | err = (skb_res == NULL) ? -EAGAIN : 1; | |
1da177e4 LT |
256 | } |
257 | neigh_release(n); | |
dbedbe6d | 258 | return err; |
1da177e4 LT |
259 | } |
260 | ||
3b04ddde | 261 | static inline int teql_resolve(struct sk_buff *skb, |
f7e57044 ED |
262 | struct sk_buff *skb_res, |
263 | struct net_device *dev, | |
264 | struct netdev_queue *txq) | |
1da177e4 | 265 | { |
f7e57044 | 266 | struct dst_entry *dst = skb_dst(skb); |
f7e57044 ED |
267 | int res; |
268 | ||
e8a0464c | 269 | if (txq->qdisc == &noop_qdisc) |
4f9f8311 EP |
270 | return -ENODEV; |
271 | ||
f7e57044 | 272 | if (!dev->header_ops || !dst) |
1da177e4 | 273 | return 0; |
f7e57044 ED |
274 | |
275 | rcu_read_lock(); | |
dbedbe6d | 276 | res = __teql_resolve(skb, skb_res, dev, txq, dst); |
f7e57044 ED |
277 | rcu_read_unlock(); |
278 | ||
279 | return res; | |
1da177e4 LT |
280 | } |
281 | ||
6fef4c0c | 282 | static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev) |
1da177e4 | 283 | { |
2941a486 | 284 | struct teql_master *master = netdev_priv(dev); |
1da177e4 LT |
285 | struct Qdisc *start, *q; |
286 | int busy; | |
287 | int nores; | |
4e3ab47a | 288 | int subq = skb_get_queue_mapping(skb); |
1da177e4 LT |
289 | struct sk_buff *skb_res = NULL; |
290 | ||
291 | start = master->slaves; | |
292 | ||
293 | restart: | |
294 | nores = 0; | |
295 | busy = 0; | |
296 | ||
cc7ec456 ED |
297 | q = start; |
298 | if (!q) | |
1da177e4 LT |
299 | goto drop; |
300 | ||
301 | do { | |
5ce2d488 | 302 | struct net_device *slave = qdisc_dev(q); |
61294e2e | 303 | struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0); |
10297b99 | 304 | |
e8a0464c | 305 | if (slave_txq->qdisc_sleeping != q) |
1da177e4 | 306 | continue; |
73466498 | 307 | if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) || |
f25f4e44 | 308 | !netif_running(slave)) { |
1da177e4 LT |
309 | busy = 1; |
310 | continue; | |
311 | } | |
312 | ||
f7e57044 | 313 | switch (teql_resolve(skb, skb_res, slave, slave_txq)) { |
1da177e4 | 314 | case 0: |
c3f26a26 | 315 | if (__netif_tx_trylock(slave_txq)) { |
c0f84d0d ED |
316 | unsigned int length = qdisc_pkt_len(skb); |
317 | ||
73466498 | 318 | if (!netif_xmit_frozen_or_stopped(slave_txq) && |
10b3ad8c | 319 | netdev_start_xmit(skb, slave, slave_txq) == NETDEV_TX_OK) { |
c3f26a26 | 320 | __netif_tx_unlock(slave_txq); |
1da177e4 LT |
321 | master->slaves = NEXT_SLAVE(q); |
322 | netif_wake_queue(dev); | |
1ac9ad13 ED |
323 | master->tx_packets++; |
324 | master->tx_bytes += length; | |
6ed10654 | 325 | return NETDEV_TX_OK; |
1da177e4 | 326 | } |
c3f26a26 | 327 | __netif_tx_unlock(slave_txq); |
1da177e4 | 328 | } |
73466498 | 329 | if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0))) |
1da177e4 LT |
330 | busy = 1; |
331 | break; | |
332 | case 1: | |
333 | master->slaves = NEXT_SLAVE(q); | |
6ed10654 | 334 | return NETDEV_TX_OK; |
1da177e4 LT |
335 | default: |
336 | nores = 1; | |
337 | break; | |
338 | } | |
bbe735e4 | 339 | __skb_pull(skb, skb_network_offset(skb)); |
1da177e4 LT |
340 | } while ((q = NEXT_SLAVE(q)) != start); |
341 | ||
342 | if (nores && skb_res == NULL) { | |
343 | skb_res = skb; | |
344 | goto restart; | |
345 | } | |
346 | ||
347 | if (busy) { | |
348 | netif_stop_queue(dev); | |
5b548140 | 349 | return NETDEV_TX_BUSY; |
1da177e4 | 350 | } |
1ac9ad13 | 351 | master->tx_errors++; |
1da177e4 LT |
352 | |
353 | drop: | |
1ac9ad13 | 354 | master->tx_dropped++; |
1da177e4 | 355 | dev_kfree_skb(skb); |
6ed10654 | 356 | return NETDEV_TX_OK; |
1da177e4 LT |
357 | } |
358 | ||
359 | static int teql_master_open(struct net_device *dev) | |
360 | { | |
cc7ec456 | 361 | struct Qdisc *q; |
2941a486 | 362 | struct teql_master *m = netdev_priv(dev); |
1da177e4 | 363 | int mtu = 0xFFFE; |
cc7ec456 | 364 | unsigned int flags = IFF_NOARP | IFF_MULTICAST; |
1da177e4 LT |
365 | |
366 | if (m->slaves == NULL) | |
367 | return -EUNATCH; | |
368 | ||
369 | flags = FMASK; | |
370 | ||
371 | q = m->slaves; | |
372 | do { | |
5ce2d488 | 373 | struct net_device *slave = qdisc_dev(q); |
1da177e4 LT |
374 | |
375 | if (slave == NULL) | |
376 | return -EUNATCH; | |
377 | ||
378 | if (slave->mtu < mtu) | |
379 | mtu = slave->mtu; | |
380 | if (slave->hard_header_len > LL_MAX_HEADER) | |
381 | return -EINVAL; | |
382 | ||
383 | /* If all the slaves are BROADCAST, master is BROADCAST | |
384 | If all the slaves are PtP, master is PtP | |
385 | Otherwise, master is NBMA. | |
386 | */ | |
387 | if (!(slave->flags&IFF_POINTOPOINT)) | |
388 | flags &= ~IFF_POINTOPOINT; | |
389 | if (!(slave->flags&IFF_BROADCAST)) | |
390 | flags &= ~IFF_BROADCAST; | |
391 | if (!(slave->flags&IFF_MULTICAST)) | |
392 | flags &= ~IFF_MULTICAST; | |
393 | } while ((q = NEXT_SLAVE(q)) != m->slaves); | |
394 | ||
395 | m->dev->mtu = mtu; | |
396 | m->dev->flags = (m->dev->flags&~FMASK) | flags; | |
397 | netif_start_queue(m->dev); | |
398 | return 0; | |
399 | } | |
400 | ||
401 | static int teql_master_close(struct net_device *dev) | |
402 | { | |
403 | netif_stop_queue(dev); | |
404 | return 0; | |
405 | } | |
406 | ||
1ac9ad13 ED |
407 | static struct rtnl_link_stats64 *teql_master_stats64(struct net_device *dev, |
408 | struct rtnl_link_stats64 *stats) | |
409 | { | |
410 | struct teql_master *m = netdev_priv(dev); | |
411 | ||
412 | stats->tx_packets = m->tx_packets; | |
413 | stats->tx_bytes = m->tx_bytes; | |
414 | stats->tx_errors = m->tx_errors; | |
415 | stats->tx_dropped = m->tx_dropped; | |
416 | return stats; | |
417 | } | |
418 | ||
1da177e4 LT |
419 | static int teql_master_mtu(struct net_device *dev, int new_mtu) |
420 | { | |
2941a486 | 421 | struct teql_master *m = netdev_priv(dev); |
1da177e4 LT |
422 | struct Qdisc *q; |
423 | ||
424 | if (new_mtu < 68) | |
425 | return -EINVAL; | |
426 | ||
427 | q = m->slaves; | |
428 | if (q) { | |
429 | do { | |
5ce2d488 | 430 | if (new_mtu > qdisc_dev(q)->mtu) |
1da177e4 | 431 | return -EINVAL; |
cc7ec456 | 432 | } while ((q = NEXT_SLAVE(q)) != m->slaves); |
1da177e4 LT |
433 | } |
434 | ||
435 | dev->mtu = new_mtu; | |
436 | return 0; | |
437 | } | |
438 | ||
61294e2e SH |
439 | static const struct net_device_ops teql_netdev_ops = { |
440 | .ndo_open = teql_master_open, | |
441 | .ndo_stop = teql_master_close, | |
442 | .ndo_start_xmit = teql_master_xmit, | |
1ac9ad13 | 443 | .ndo_get_stats64 = teql_master_stats64, |
61294e2e SH |
444 | .ndo_change_mtu = teql_master_mtu, |
445 | }; | |
446 | ||
1da177e4 LT |
447 | static __init void teql_master_setup(struct net_device *dev) |
448 | { | |
2941a486 | 449 | struct teql_master *master = netdev_priv(dev); |
1da177e4 LT |
450 | struct Qdisc_ops *ops = &master->qops; |
451 | ||
452 | master->dev = dev; | |
453 | ops->priv_size = sizeof(struct teql_sched_data); | |
10297b99 | 454 | |
1da177e4 LT |
455 | ops->enqueue = teql_enqueue; |
456 | ops->dequeue = teql_dequeue; | |
8e3af978 | 457 | ops->peek = teql_peek; |
1da177e4 LT |
458 | ops->init = teql_qdisc_init; |
459 | ops->reset = teql_reset; | |
460 | ops->destroy = teql_destroy; | |
461 | ops->owner = THIS_MODULE; | |
462 | ||
61294e2e | 463 | dev->netdev_ops = &teql_netdev_ops; |
1da177e4 LT |
464 | dev->type = ARPHRD_VOID; |
465 | dev->mtu = 1500; | |
466 | dev->tx_queue_len = 100; | |
467 | dev->flags = IFF_NOARP; | |
468 | dev->hard_header_len = LL_MAX_HEADER; | |
fa68a782 | 469 | dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; |
1da177e4 LT |
470 | } |
471 | ||
472 | static LIST_HEAD(master_dev_list); | |
473 | static int max_equalizers = 1; | |
474 | module_param(max_equalizers, int, 0); | |
475 | MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers"); | |
476 | ||
477 | static int __init teql_init(void) | |
478 | { | |
479 | int i; | |
480 | int err = -ENODEV; | |
481 | ||
482 | for (i = 0; i < max_equalizers; i++) { | |
483 | struct net_device *dev; | |
484 | struct teql_master *master; | |
485 | ||
c835a677 TG |
486 | dev = alloc_netdev(sizeof(struct teql_master), "teql%d", |
487 | NET_NAME_UNKNOWN, teql_master_setup); | |
1da177e4 LT |
488 | if (!dev) { |
489 | err = -ENOMEM; | |
490 | break; | |
491 | } | |
492 | ||
493 | if ((err = register_netdev(dev))) { | |
494 | free_netdev(dev); | |
495 | break; | |
496 | } | |
497 | ||
2941a486 | 498 | master = netdev_priv(dev); |
1da177e4 LT |
499 | |
500 | strlcpy(master->qops.id, dev->name, IFNAMSIZ); | |
501 | err = register_qdisc(&master->qops); | |
502 | ||
503 | if (err) { | |
504 | unregister_netdev(dev); | |
505 | free_netdev(dev); | |
506 | break; | |
507 | } | |
508 | ||
509 | list_add_tail(&master->master_list, &master_dev_list); | |
510 | } | |
511 | return i ? 0 : err; | |
512 | } | |
513 | ||
10297b99 | 514 | static void __exit teql_exit(void) |
1da177e4 LT |
515 | { |
516 | struct teql_master *master, *nxt; | |
517 | ||
518 | list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) { | |
519 | ||
520 | list_del(&master->master_list); | |
521 | ||
522 | unregister_qdisc(&master->qops); | |
523 | unregister_netdev(master->dev); | |
524 | free_netdev(master->dev); | |
525 | } | |
526 | } | |
527 | ||
528 | module_init(teql_init); | |
529 | module_exit(teql_exit); | |
530 | ||
531 | MODULE_LICENSE("GPL"); |