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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>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <linux/string.h>
16#include <linux/errno.h>
17#include <linux/if_arp.h>
18#include <linux/netdevice.h>
19#include <linux/init.h>
20#include <linux/skbuff.h>
21#include <linux/moduleparam.h>
22#include <net/dst.h>
23#include <net/neighbour.h>
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
56struct teql_master {
57 struct Qdisc_ops qops;
58 struct net_device *dev;
59 struct Qdisc *slaves;
60 struct list_head master_list;
61 unsigned long tx_bytes;
62 unsigned long tx_packets;
63 unsigned long tx_errors;
64 unsigned long tx_dropped;
65};
66
67struct teql_sched_data {
68 struct Qdisc *next;
69 struct teql_master *m;
70 struct sk_buff_head q;
71};
72
73#define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next)
74
75#define FMASK (IFF_BROADCAST | IFF_POINTOPOINT)
76
77/* "teql*" qdisc routines */
78
79static int
80teql_enqueue(struct sk_buff *skb, struct Qdisc *sch)
81{
82 struct net_device *dev = qdisc_dev(sch);
83 struct teql_sched_data *q = qdisc_priv(sch);
84
85 if (q->q.qlen < dev->tx_queue_len) {
86 __skb_queue_tail(&q->q, skb);
87 return NET_XMIT_SUCCESS;
88 }
89
90 return qdisc_drop(skb, sch);
91}
92
93static struct sk_buff *
94teql_dequeue(struct Qdisc *sch)
95{
96 struct teql_sched_data *dat = qdisc_priv(sch);
97 struct netdev_queue *dat_queue;
98 struct sk_buff *skb;
99 struct Qdisc *q;
100
101 skb = __skb_dequeue(&dat->q);
102 dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
103 q = rcu_dereference_bh(dat_queue->qdisc);
104
105 if (skb == NULL) {
106 struct net_device *m = qdisc_dev(q);
107 if (m) {
108 dat->m->slaves = sch;
109 netif_wake_queue(m);
110 }
111 } else {
112 qdisc_bstats_update(sch, skb);
113 }
114 sch->q.qlen = dat->q.qlen + q->q.qlen;
115 return skb;
116}
117
118static struct sk_buff *
119teql_peek(struct Qdisc *sch)
120{
121 /* teql is meant to be used as root qdisc */
122 return NULL;
123}
124
125static void
126teql_reset(struct Qdisc *sch)
127{
128 struct teql_sched_data *dat = qdisc_priv(sch);
129
130 skb_queue_purge(&dat->q);
131 sch->q.qlen = 0;
132}
133
134static void
135teql_destroy(struct Qdisc *sch)
136{
137 struct Qdisc *q, *prev;
138 struct teql_sched_data *dat = qdisc_priv(sch);
139 struct teql_master *master = dat->m;
140
141 prev = master->slaves;
142 if (prev) {
143 do {
144 q = NEXT_SLAVE(prev);
145 if (q == sch) {
146 NEXT_SLAVE(prev) = NEXT_SLAVE(q);
147 if (q == master->slaves) {
148 master->slaves = NEXT_SLAVE(q);
149 if (q == master->slaves) {
150 struct netdev_queue *txq;
151 spinlock_t *root_lock;
152
153 txq = netdev_get_tx_queue(master->dev, 0);
154 master->slaves = NULL;
155
156 root_lock = qdisc_root_sleeping_lock(rtnl_dereference(txq->qdisc));
157 spin_lock_bh(root_lock);
158 qdisc_reset(rtnl_dereference(txq->qdisc));
159 spin_unlock_bh(root_lock);
160 }
161 }
162 skb_queue_purge(&dat->q);
163 break;
164 }
165
166 } while ((prev = q) != master->slaves);
167 }
168}
169
170static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt)
171{
172 struct net_device *dev = qdisc_dev(sch);
173 struct teql_master *m = (struct teql_master *)sch->ops;
174 struct teql_sched_data *q = qdisc_priv(sch);
175
176 if (dev->hard_header_len > m->dev->hard_header_len)
177 return -EINVAL;
178
179 if (m->dev == dev)
180 return -ELOOP;
181
182 q->m = m;
183
184 skb_queue_head_init(&q->q);
185
186 if (m->slaves) {
187 if (m->dev->flags & IFF_UP) {
188 if ((m->dev->flags & IFF_POINTOPOINT &&
189 !(dev->flags & IFF_POINTOPOINT)) ||
190 (m->dev->flags & IFF_BROADCAST &&
191 !(dev->flags & IFF_BROADCAST)) ||
192 (m->dev->flags & IFF_MULTICAST &&
193 !(dev->flags & IFF_MULTICAST)) ||
194 dev->mtu < m->dev->mtu)
195 return -EINVAL;
196 } else {
197 if (!(dev->flags&IFF_POINTOPOINT))
198 m->dev->flags &= ~IFF_POINTOPOINT;
199 if (!(dev->flags&IFF_BROADCAST))
200 m->dev->flags &= ~IFF_BROADCAST;
201 if (!(dev->flags&IFF_MULTICAST))
202 m->dev->flags &= ~IFF_MULTICAST;
203 if (dev->mtu < m->dev->mtu)
204 m->dev->mtu = dev->mtu;
205 }
206 q->next = NEXT_SLAVE(m->slaves);
207 NEXT_SLAVE(m->slaves) = sch;
208 } else {
209 q->next = sch;
210 m->slaves = sch;
211 m->dev->mtu = dev->mtu;
212 m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
213 }
214 return 0;
215}
216
217
218static int
219__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
220 struct net_device *dev, struct netdev_queue *txq,
221 struct dst_entry *dst)
222{
223 struct neighbour *n;
224 int err = 0;
225
226 n = dst_neigh_lookup_skb(dst, skb);
227 if (!n)
228 return -ENOENT;
229
230 if (dst->dev != dev) {
231 struct neighbour *mn;
232
233 mn = __neigh_lookup_errno(n->tbl, n->primary_key, dev);
234 neigh_release(n);
235 if (IS_ERR(mn))
236 return PTR_ERR(mn);
237 n = mn;
238 }
239
240 if (neigh_event_send(n, skb_res) == 0) {
241 int err;
242 char haddr[MAX_ADDR_LEN];
243
244 neigh_ha_snapshot(haddr, n, dev);
245 err = dev_hard_header(skb, dev, ntohs(tc_skb_protocol(skb)),
246 haddr, NULL, skb->len);
247
248 if (err < 0)
249 err = -EINVAL;
250 } else {
251 err = (skb_res == NULL) ? -EAGAIN : 1;
252 }
253 neigh_release(n);
254 return err;
255}
256
257static inline int teql_resolve(struct sk_buff *skb,
258 struct sk_buff *skb_res,
259 struct net_device *dev,
260 struct netdev_queue *txq)
261{
262 struct dst_entry *dst = skb_dst(skb);
263 int res;
264
265 if (rcu_access_pointer(txq->qdisc) == &noop_qdisc)
266 return -ENODEV;
267
268 if (!dev->header_ops || !dst)
269 return 0;
270
271 rcu_read_lock();
272 res = __teql_resolve(skb, skb_res, dev, txq, dst);
273 rcu_read_unlock();
274
275 return res;
276}
277
278static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
279{
280 struct teql_master *master = netdev_priv(dev);
281 struct Qdisc *start, *q;
282 int busy;
283 int nores;
284 int subq = skb_get_queue_mapping(skb);
285 struct sk_buff *skb_res = NULL;
286
287 start = master->slaves;
288
289restart:
290 nores = 0;
291 busy = 0;
292
293 q = start;
294 if (!q)
295 goto drop;
296
297 do {
298 struct net_device *slave = qdisc_dev(q);
299 struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
300
301 if (slave_txq->qdisc_sleeping != q)
302 continue;
303 if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
304 !netif_running(slave)) {
305 busy = 1;
306 continue;
307 }
308
309 switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
310 case 0:
311 if (__netif_tx_trylock(slave_txq)) {
312 unsigned int length = qdisc_pkt_len(skb);
313
314 if (!netif_xmit_frozen_or_stopped(slave_txq) &&
315 netdev_start_xmit(skb, slave, slave_txq, false) ==
316 NETDEV_TX_OK) {
317 __netif_tx_unlock(slave_txq);
318 master->slaves = NEXT_SLAVE(q);
319 netif_wake_queue(dev);
320 master->tx_packets++;
321 master->tx_bytes += length;
322 return NETDEV_TX_OK;
323 }
324 __netif_tx_unlock(slave_txq);
325 }
326 if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
327 busy = 1;
328 break;
329 case 1:
330 master->slaves = NEXT_SLAVE(q);
331 return NETDEV_TX_OK;
332 default:
333 nores = 1;
334 break;
335 }
336 __skb_pull(skb, skb_network_offset(skb));
337 } while ((q = NEXT_SLAVE(q)) != start);
338
339 if (nores && skb_res == NULL) {
340 skb_res = skb;
341 goto restart;
342 }
343
344 if (busy) {
345 netif_stop_queue(dev);
346 return NETDEV_TX_BUSY;
347 }
348 master->tx_errors++;
349
350drop:
351 master->tx_dropped++;
352 dev_kfree_skb(skb);
353 return NETDEV_TX_OK;
354}
355
356static int teql_master_open(struct net_device *dev)
357{
358 struct Qdisc *q;
359 struct teql_master *m = netdev_priv(dev);
360 int mtu = 0xFFFE;
361 unsigned int flags = IFF_NOARP | IFF_MULTICAST;
362
363 if (m->slaves == NULL)
364 return -EUNATCH;
365
366 flags = FMASK;
367
368 q = m->slaves;
369 do {
370 struct net_device *slave = qdisc_dev(q);
371
372 if (slave == NULL)
373 return -EUNATCH;
374
375 if (slave->mtu < mtu)
376 mtu = slave->mtu;
377 if (slave->hard_header_len > LL_MAX_HEADER)
378 return -EINVAL;
379
380 /* If all the slaves are BROADCAST, master is BROADCAST
381 If all the slaves are PtP, master is PtP
382 Otherwise, master is NBMA.
383 */
384 if (!(slave->flags&IFF_POINTOPOINT))
385 flags &= ~IFF_POINTOPOINT;
386 if (!(slave->flags&IFF_BROADCAST))
387 flags &= ~IFF_BROADCAST;
388 if (!(slave->flags&IFF_MULTICAST))
389 flags &= ~IFF_MULTICAST;
390 } while ((q = NEXT_SLAVE(q)) != m->slaves);
391
392 m->dev->mtu = mtu;
393 m->dev->flags = (m->dev->flags&~FMASK) | flags;
394 netif_start_queue(m->dev);
395 return 0;
396}
397
398static int teql_master_close(struct net_device *dev)
399{
400 netif_stop_queue(dev);
401 return 0;
402}
403
404static struct rtnl_link_stats64 *teql_master_stats64(struct net_device *dev,
405 struct rtnl_link_stats64 *stats)
406{
407 struct teql_master *m = netdev_priv(dev);
408
409 stats->tx_packets = m->tx_packets;
410 stats->tx_bytes = m->tx_bytes;
411 stats->tx_errors = m->tx_errors;
412 stats->tx_dropped = m->tx_dropped;
413 return stats;
414}
415
416static int teql_master_mtu(struct net_device *dev, int new_mtu)
417{
418 struct teql_master *m = netdev_priv(dev);
419 struct Qdisc *q;
420
421 if (new_mtu < 68)
422 return -EINVAL;
423
424 q = m->slaves;
425 if (q) {
426 do {
427 if (new_mtu > qdisc_dev(q)->mtu)
428 return -EINVAL;
429 } while ((q = NEXT_SLAVE(q)) != m->slaves);
430 }
431
432 dev->mtu = new_mtu;
433 return 0;
434}
435
436static const struct net_device_ops teql_netdev_ops = {
437 .ndo_open = teql_master_open,
438 .ndo_stop = teql_master_close,
439 .ndo_start_xmit = teql_master_xmit,
440 .ndo_get_stats64 = teql_master_stats64,
441 .ndo_change_mtu = teql_master_mtu,
442};
443
444static __init void teql_master_setup(struct net_device *dev)
445{
446 struct teql_master *master = netdev_priv(dev);
447 struct Qdisc_ops *ops = &master->qops;
448
449 master->dev = dev;
450 ops->priv_size = sizeof(struct teql_sched_data);
451
452 ops->enqueue = teql_enqueue;
453 ops->dequeue = teql_dequeue;
454 ops->peek = teql_peek;
455 ops->init = teql_qdisc_init;
456 ops->reset = teql_reset;
457 ops->destroy = teql_destroy;
458 ops->owner = THIS_MODULE;
459
460 dev->netdev_ops = &teql_netdev_ops;
461 dev->type = ARPHRD_VOID;
462 dev->mtu = 1500;
463 dev->tx_queue_len = 100;
464 dev->flags = IFF_NOARP;
465 dev->hard_header_len = LL_MAX_HEADER;
466 netif_keep_dst(dev);
467}
468
469static LIST_HEAD(master_dev_list);
470static int max_equalizers = 1;
471module_param(max_equalizers, int, 0);
472MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
473
474static int __init teql_init(void)
475{
476 int i;
477 int err = -ENODEV;
478
479 for (i = 0; i < max_equalizers; i++) {
480 struct net_device *dev;
481 struct teql_master *master;
482
483 dev = alloc_netdev(sizeof(struct teql_master), "teql%d",
484 NET_NAME_UNKNOWN, teql_master_setup);
485 if (!dev) {
486 err = -ENOMEM;
487 break;
488 }
489
490 if ((err = register_netdev(dev))) {
491 free_netdev(dev);
492 break;
493 }
494
495 master = netdev_priv(dev);
496
497 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
498 err = register_qdisc(&master->qops);
499
500 if (err) {
501 unregister_netdev(dev);
502 free_netdev(dev);
503 break;
504 }
505
506 list_add_tail(&master->master_list, &master_dev_list);
507 }
508 return i ? 0 : err;
509}
510
511static void __exit teql_exit(void)
512{
513 struct teql_master *master, *nxt;
514
515 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
516
517 list_del(&master->master_list);
518
519 unregister_qdisc(&master->qops);
520 unregister_netdev(master->dev);
521 free_netdev(master->dev);
522 }
523}
524
525module_init(teql_init);
526module_exit(teql_exit);
527
528MODULE_LICENSE("GPL");
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>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/slab.h>
15#include <linux/string.h>
16#include <linux/errno.h>
17#include <linux/if_arp.h>
18#include <linux/netdevice.h>
19#include <linux/init.h>
20#include <linux/skbuff.h>
21#include <linux/moduleparam.h>
22#include <net/dst.h>
23#include <net/neighbour.h>
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
56struct teql_master {
57 struct Qdisc_ops qops;
58 struct net_device *dev;
59 struct Qdisc *slaves;
60 struct list_head master_list;
61 unsigned long tx_bytes;
62 unsigned long tx_packets;
63 unsigned long tx_errors;
64 unsigned long tx_dropped;
65};
66
67struct teql_sched_data {
68 struct Qdisc *next;
69 struct teql_master *m;
70 struct sk_buff_head q;
71};
72
73#define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next)
74
75#define FMASK (IFF_BROADCAST | IFF_POINTOPOINT)
76
77/* "teql*" qdisc routines */
78
79static int
80teql_enqueue(struct sk_buff *skb, struct Qdisc *sch)
81{
82 struct net_device *dev = qdisc_dev(sch);
83 struct teql_sched_data *q = qdisc_priv(sch);
84
85 if (q->q.qlen < dev->tx_queue_len) {
86 __skb_queue_tail(&q->q, skb);
87 return NET_XMIT_SUCCESS;
88 }
89
90 return qdisc_drop(skb, sch);
91}
92
93static struct sk_buff *
94teql_dequeue(struct Qdisc *sch)
95{
96 struct teql_sched_data *dat = qdisc_priv(sch);
97 struct netdev_queue *dat_queue;
98 struct sk_buff *skb;
99
100 skb = __skb_dequeue(&dat->q);
101 dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
102 if (skb == NULL) {
103 struct net_device *m = qdisc_dev(dat_queue->qdisc);
104 if (m) {
105 dat->m->slaves = sch;
106 netif_wake_queue(m);
107 }
108 } else {
109 qdisc_bstats_update(sch, skb);
110 }
111 sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen;
112 return skb;
113}
114
115static struct sk_buff *
116teql_peek(struct Qdisc *sch)
117{
118 /* teql is meant to be used as root qdisc */
119 return NULL;
120}
121
122static inline void
123teql_neigh_release(struct neighbour *n)
124{
125 if (n)
126 neigh_release(n);
127}
128
129static void
130teql_reset(struct Qdisc *sch)
131{
132 struct teql_sched_data *dat = qdisc_priv(sch);
133
134 skb_queue_purge(&dat->q);
135 sch->q.qlen = 0;
136}
137
138static void
139teql_destroy(struct Qdisc *sch)
140{
141 struct Qdisc *q, *prev;
142 struct teql_sched_data *dat = qdisc_priv(sch);
143 struct teql_master *master = dat->m;
144
145 prev = master->slaves;
146 if (prev) {
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) {
154 struct netdev_queue *txq;
155 spinlock_t *root_lock;
156
157 txq = netdev_get_tx_queue(master->dev, 0);
158 master->slaves = NULL;
159
160 root_lock = qdisc_root_sleeping_lock(txq->qdisc);
161 spin_lock_bh(root_lock);
162 qdisc_reset(txq->qdisc);
163 spin_unlock_bh(root_lock);
164 }
165 }
166 skb_queue_purge(&dat->q);
167 break;
168 }
169
170 } while ((prev = q) != master->slaves);
171 }
172}
173
174static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt)
175{
176 struct net_device *dev = qdisc_dev(sch);
177 struct teql_master *m = (struct teql_master *)sch->ops;
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) {
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)
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
221
222static int
223__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
224 struct net_device *dev, struct netdev_queue *txq,
225 struct dst_entry *dst)
226{
227 struct neighbour *n;
228 int err = 0;
229
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;
242 }
243
244 if (neigh_event_send(n, skb_res) == 0) {
245 int err;
246 char haddr[MAX_ADDR_LEN];
247
248 neigh_ha_snapshot(haddr, n, dev);
249 err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
250 NULL, skb->len);
251
252 if (err < 0)
253 err = -EINVAL;
254 } else {
255 err = (skb_res == NULL) ? -EAGAIN : 1;
256 }
257 neigh_release(n);
258 return err;
259}
260
261static inline int teql_resolve(struct sk_buff *skb,
262 struct sk_buff *skb_res,
263 struct net_device *dev,
264 struct netdev_queue *txq)
265{
266 struct dst_entry *dst = skb_dst(skb);
267 int res;
268
269 if (txq->qdisc == &noop_qdisc)
270 return -ENODEV;
271
272 if (!dev->header_ops || !dst)
273 return 0;
274
275 rcu_read_lock();
276 res = __teql_resolve(skb, skb_res, dev, txq, dst);
277 rcu_read_unlock();
278
279 return res;
280}
281
282static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
283{
284 struct teql_master *master = netdev_priv(dev);
285 struct Qdisc *start, *q;
286 int busy;
287 int nores;
288 int subq = skb_get_queue_mapping(skb);
289 struct sk_buff *skb_res = NULL;
290
291 start = master->slaves;
292
293restart:
294 nores = 0;
295 busy = 0;
296
297 q = start;
298 if (!q)
299 goto drop;
300
301 do {
302 struct net_device *slave = qdisc_dev(q);
303 struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
304 const struct net_device_ops *slave_ops = slave->netdev_ops;
305
306 if (slave_txq->qdisc_sleeping != q)
307 continue;
308 if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
309 !netif_running(slave)) {
310 busy = 1;
311 continue;
312 }
313
314 switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
315 case 0:
316 if (__netif_tx_trylock(slave_txq)) {
317 unsigned int length = qdisc_pkt_len(skb);
318
319 if (!netif_xmit_frozen_or_stopped(slave_txq) &&
320 slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
321 txq_trans_update(slave_txq);
322 __netif_tx_unlock(slave_txq);
323 master->slaves = NEXT_SLAVE(q);
324 netif_wake_queue(dev);
325 master->tx_packets++;
326 master->tx_bytes += length;
327 return NETDEV_TX_OK;
328 }
329 __netif_tx_unlock(slave_txq);
330 }
331 if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
332 busy = 1;
333 break;
334 case 1:
335 master->slaves = NEXT_SLAVE(q);
336 return NETDEV_TX_OK;
337 default:
338 nores = 1;
339 break;
340 }
341 __skb_pull(skb, skb_network_offset(skb));
342 } while ((q = NEXT_SLAVE(q)) != start);
343
344 if (nores && skb_res == NULL) {
345 skb_res = skb;
346 goto restart;
347 }
348
349 if (busy) {
350 netif_stop_queue(dev);
351 return NETDEV_TX_BUSY;
352 }
353 master->tx_errors++;
354
355drop:
356 master->tx_dropped++;
357 dev_kfree_skb(skb);
358 return NETDEV_TX_OK;
359}
360
361static int teql_master_open(struct net_device *dev)
362{
363 struct Qdisc *q;
364 struct teql_master *m = netdev_priv(dev);
365 int mtu = 0xFFFE;
366 unsigned int flags = IFF_NOARP | IFF_MULTICAST;
367
368 if (m->slaves == NULL)
369 return -EUNATCH;
370
371 flags = FMASK;
372
373 q = m->slaves;
374 do {
375 struct net_device *slave = qdisc_dev(q);
376
377 if (slave == NULL)
378 return -EUNATCH;
379
380 if (slave->mtu < mtu)
381 mtu = slave->mtu;
382 if (slave->hard_header_len > LL_MAX_HEADER)
383 return -EINVAL;
384
385 /* If all the slaves are BROADCAST, master is BROADCAST
386 If all the slaves are PtP, master is PtP
387 Otherwise, master is NBMA.
388 */
389 if (!(slave->flags&IFF_POINTOPOINT))
390 flags &= ~IFF_POINTOPOINT;
391 if (!(slave->flags&IFF_BROADCAST))
392 flags &= ~IFF_BROADCAST;
393 if (!(slave->flags&IFF_MULTICAST))
394 flags &= ~IFF_MULTICAST;
395 } while ((q = NEXT_SLAVE(q)) != m->slaves);
396
397 m->dev->mtu = mtu;
398 m->dev->flags = (m->dev->flags&~FMASK) | flags;
399 netif_start_queue(m->dev);
400 return 0;
401}
402
403static int teql_master_close(struct net_device *dev)
404{
405 netif_stop_queue(dev);
406 return 0;
407}
408
409static struct rtnl_link_stats64 *teql_master_stats64(struct net_device *dev,
410 struct rtnl_link_stats64 *stats)
411{
412 struct teql_master *m = netdev_priv(dev);
413
414 stats->tx_packets = m->tx_packets;
415 stats->tx_bytes = m->tx_bytes;
416 stats->tx_errors = m->tx_errors;
417 stats->tx_dropped = m->tx_dropped;
418 return stats;
419}
420
421static int teql_master_mtu(struct net_device *dev, int new_mtu)
422{
423 struct teql_master *m = netdev_priv(dev);
424 struct Qdisc *q;
425
426 if (new_mtu < 68)
427 return -EINVAL;
428
429 q = m->slaves;
430 if (q) {
431 do {
432 if (new_mtu > qdisc_dev(q)->mtu)
433 return -EINVAL;
434 } while ((q = NEXT_SLAVE(q)) != m->slaves);
435 }
436
437 dev->mtu = new_mtu;
438 return 0;
439}
440
441static const struct net_device_ops teql_netdev_ops = {
442 .ndo_open = teql_master_open,
443 .ndo_stop = teql_master_close,
444 .ndo_start_xmit = teql_master_xmit,
445 .ndo_get_stats64 = teql_master_stats64,
446 .ndo_change_mtu = teql_master_mtu,
447};
448
449static __init void teql_master_setup(struct net_device *dev)
450{
451 struct teql_master *master = netdev_priv(dev);
452 struct Qdisc_ops *ops = &master->qops;
453
454 master->dev = dev;
455 ops->priv_size = sizeof(struct teql_sched_data);
456
457 ops->enqueue = teql_enqueue;
458 ops->dequeue = teql_dequeue;
459 ops->peek = teql_peek;
460 ops->init = teql_qdisc_init;
461 ops->reset = teql_reset;
462 ops->destroy = teql_destroy;
463 ops->owner = THIS_MODULE;
464
465 dev->netdev_ops = &teql_netdev_ops;
466 dev->type = ARPHRD_VOID;
467 dev->mtu = 1500;
468 dev->tx_queue_len = 100;
469 dev->flags = IFF_NOARP;
470 dev->hard_header_len = LL_MAX_HEADER;
471 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
472}
473
474static LIST_HEAD(master_dev_list);
475static int max_equalizers = 1;
476module_param(max_equalizers, int, 0);
477MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
478
479static int __init teql_init(void)
480{
481 int i;
482 int err = -ENODEV;
483
484 for (i = 0; i < max_equalizers; i++) {
485 struct net_device *dev;
486 struct teql_master *master;
487
488 dev = alloc_netdev(sizeof(struct teql_master),
489 "teql%d", teql_master_setup);
490 if (!dev) {
491 err = -ENOMEM;
492 break;
493 }
494
495 if ((err = register_netdev(dev))) {
496 free_netdev(dev);
497 break;
498 }
499
500 master = netdev_priv(dev);
501
502 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
503 err = register_qdisc(&master->qops);
504
505 if (err) {
506 unregister_netdev(dev);
507 free_netdev(dev);
508 break;
509 }
510
511 list_add_tail(&master->master_list, &master_dev_list);
512 }
513 return i ? 0 : err;
514}
515
516static void __exit teql_exit(void)
517{
518 struct teql_master *master, *nxt;
519
520 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
521
522 list_del(&master->master_list);
523
524 unregister_qdisc(&master->qops);
525 unregister_netdev(master->dev);
526 free_netdev(master->dev);
527 }
528}
529
530module_init(teql_init);
531module_exit(teql_exit);
532
533MODULE_LICENSE("GPL");