Loading...
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 neighbour *ncache;
71 struct sk_buff_head q;
72};
73
74#define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next)
75
76#define FMASK (IFF_BROADCAST | IFF_POINTOPOINT)
77
78/* "teql*" qdisc routines */
79
80static int
81teql_enqueue(struct sk_buff *skb, struct Qdisc *sch)
82{
83 struct net_device *dev = qdisc_dev(sch);
84 struct teql_sched_data *q = qdisc_priv(sch);
85
86 if (q->q.qlen < dev->tx_queue_len) {
87 __skb_queue_tail(&q->q, skb);
88 return NET_XMIT_SUCCESS;
89 }
90
91 return qdisc_drop(skb, sch);
92}
93
94static struct sk_buff *
95teql_dequeue(struct Qdisc *sch)
96{
97 struct teql_sched_data *dat = qdisc_priv(sch);
98 struct netdev_queue *dat_queue;
99 struct sk_buff *skb;
100
101 skb = __skb_dequeue(&dat->q);
102 dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
103 if (skb == NULL) {
104 struct net_device *m = qdisc_dev(dat_queue->qdisc);
105 if (m) {
106 dat->m->slaves = sch;
107 netif_wake_queue(m);
108 }
109 } else {
110 qdisc_bstats_update(sch, skb);
111 }
112 sch->q.qlen = dat->q.qlen + dat_queue->qdisc->q.qlen;
113 return skb;
114}
115
116static struct sk_buff *
117teql_peek(struct Qdisc *sch)
118{
119 /* teql is meant to be used as root qdisc */
120 return NULL;
121}
122
123static inline void
124teql_neigh_release(struct neighbour *n)
125{
126 if (n)
127 neigh_release(n);
128}
129
130static void
131teql_reset(struct Qdisc *sch)
132{
133 struct teql_sched_data *dat = qdisc_priv(sch);
134
135 skb_queue_purge(&dat->q);
136 sch->q.qlen = 0;
137 teql_neigh_release(xchg(&dat->ncache, NULL));
138}
139
140static void
141teql_destroy(struct Qdisc *sch)
142{
143 struct Qdisc *q, *prev;
144 struct teql_sched_data *dat = qdisc_priv(sch);
145 struct teql_master *master = dat->m;
146
147 prev = master->slaves;
148 if (prev) {
149 do {
150 q = NEXT_SLAVE(prev);
151 if (q == sch) {
152 NEXT_SLAVE(prev) = NEXT_SLAVE(q);
153 if (q == master->slaves) {
154 master->slaves = NEXT_SLAVE(q);
155 if (q == master->slaves) {
156 struct netdev_queue *txq;
157 spinlock_t *root_lock;
158
159 txq = netdev_get_tx_queue(master->dev, 0);
160 master->slaves = NULL;
161
162 root_lock = qdisc_root_sleeping_lock(txq->qdisc);
163 spin_lock_bh(root_lock);
164 qdisc_reset(txq->qdisc);
165 spin_unlock_bh(root_lock);
166 }
167 }
168 skb_queue_purge(&dat->q);
169 teql_neigh_release(xchg(&dat->ncache, NULL));
170 break;
171 }
172
173 } while ((prev = q) != master->slaves);
174 }
175}
176
177static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt)
178{
179 struct net_device *dev = qdisc_dev(sch);
180 struct teql_master *m = (struct teql_master *)sch->ops;
181 struct teql_sched_data *q = qdisc_priv(sch);
182
183 if (dev->hard_header_len > m->dev->hard_header_len)
184 return -EINVAL;
185
186 if (m->dev == dev)
187 return -ELOOP;
188
189 q->m = m;
190
191 skb_queue_head_init(&q->q);
192
193 if (m->slaves) {
194 if (m->dev->flags & IFF_UP) {
195 if ((m->dev->flags & IFF_POINTOPOINT &&
196 !(dev->flags & IFF_POINTOPOINT)) ||
197 (m->dev->flags & IFF_BROADCAST &&
198 !(dev->flags & IFF_BROADCAST)) ||
199 (m->dev->flags & IFF_MULTICAST &&
200 !(dev->flags & IFF_MULTICAST)) ||
201 dev->mtu < m->dev->mtu)
202 return -EINVAL;
203 } else {
204 if (!(dev->flags&IFF_POINTOPOINT))
205 m->dev->flags &= ~IFF_POINTOPOINT;
206 if (!(dev->flags&IFF_BROADCAST))
207 m->dev->flags &= ~IFF_BROADCAST;
208 if (!(dev->flags&IFF_MULTICAST))
209 m->dev->flags &= ~IFF_MULTICAST;
210 if (dev->mtu < m->dev->mtu)
211 m->dev->mtu = dev->mtu;
212 }
213 q->next = NEXT_SLAVE(m->slaves);
214 NEXT_SLAVE(m->slaves) = sch;
215 } else {
216 q->next = sch;
217 m->slaves = sch;
218 m->dev->mtu = dev->mtu;
219 m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
220 }
221 return 0;
222}
223
224
225static int
226__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
227 struct net_device *dev, struct netdev_queue *txq,
228 struct neighbour *mn)
229{
230 struct teql_sched_data *q = qdisc_priv(txq->qdisc);
231 struct neighbour *n = q->ncache;
232
233 if (mn->tbl == NULL)
234 return -EINVAL;
235 if (n && n->tbl == mn->tbl &&
236 memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
237 atomic_inc(&n->refcnt);
238 } else {
239 n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
240 if (IS_ERR(n))
241 return PTR_ERR(n);
242 }
243 if (neigh_event_send(n, skb_res) == 0) {
244 int err;
245 char haddr[MAX_ADDR_LEN];
246
247 neigh_ha_snapshot(haddr, n, dev);
248 err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
249 NULL, skb->len);
250
251 if (err < 0) {
252 neigh_release(n);
253 return -EINVAL;
254 }
255 teql_neigh_release(xchg(&q->ncache, n));
256 return 0;
257 }
258 neigh_release(n);
259 return (skb_res == NULL) ? -EAGAIN : 1;
260}
261
262static inline int teql_resolve(struct sk_buff *skb,
263 struct sk_buff *skb_res,
264 struct net_device *dev,
265 struct netdev_queue *txq)
266{
267 struct dst_entry *dst = skb_dst(skb);
268 struct neighbour *mn;
269 int res;
270
271 if (txq->qdisc == &noop_qdisc)
272 return -ENODEV;
273
274 if (!dev->header_ops || !dst)
275 return 0;
276
277 rcu_read_lock();
278 mn = dst_get_neighbour_noref(dst);
279 res = mn ? __teql_resolve(skb, skb_res, dev, txq, mn) : 0;
280 rcu_read_unlock();
281
282 return res;
283}
284
285static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
286{
287 struct teql_master *master = netdev_priv(dev);
288 struct Qdisc *start, *q;
289 int busy;
290 int nores;
291 int subq = skb_get_queue_mapping(skb);
292 struct sk_buff *skb_res = NULL;
293
294 start = master->slaves;
295
296restart:
297 nores = 0;
298 busy = 0;
299
300 q = start;
301 if (!q)
302 goto drop;
303
304 do {
305 struct net_device *slave = qdisc_dev(q);
306 struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
307 const struct net_device_ops *slave_ops = slave->netdev_ops;
308
309 if (slave_txq->qdisc_sleeping != q)
310 continue;
311 if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
312 !netif_running(slave)) {
313 busy = 1;
314 continue;
315 }
316
317 switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
318 case 0:
319 if (__netif_tx_trylock(slave_txq)) {
320 unsigned int length = qdisc_pkt_len(skb);
321
322 if (!netif_xmit_frozen_or_stopped(slave_txq) &&
323 slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
324 txq_trans_update(slave_txq);
325 __netif_tx_unlock(slave_txq);
326 master->slaves = NEXT_SLAVE(q);
327 netif_wake_queue(dev);
328 master->tx_packets++;
329 master->tx_bytes += length;
330 return NETDEV_TX_OK;
331 }
332 __netif_tx_unlock(slave_txq);
333 }
334 if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
335 busy = 1;
336 break;
337 case 1:
338 master->slaves = NEXT_SLAVE(q);
339 return NETDEV_TX_OK;
340 default:
341 nores = 1;
342 break;
343 }
344 __skb_pull(skb, skb_network_offset(skb));
345 } while ((q = NEXT_SLAVE(q)) != start);
346
347 if (nores && skb_res == NULL) {
348 skb_res = skb;
349 goto restart;
350 }
351
352 if (busy) {
353 netif_stop_queue(dev);
354 return NETDEV_TX_BUSY;
355 }
356 master->tx_errors++;
357
358drop:
359 master->tx_dropped++;
360 dev_kfree_skb(skb);
361 return NETDEV_TX_OK;
362}
363
364static int teql_master_open(struct net_device *dev)
365{
366 struct Qdisc *q;
367 struct teql_master *m = netdev_priv(dev);
368 int mtu = 0xFFFE;
369 unsigned int flags = IFF_NOARP | IFF_MULTICAST;
370
371 if (m->slaves == NULL)
372 return -EUNATCH;
373
374 flags = FMASK;
375
376 q = m->slaves;
377 do {
378 struct net_device *slave = qdisc_dev(q);
379
380 if (slave == NULL)
381 return -EUNATCH;
382
383 if (slave->mtu < mtu)
384 mtu = slave->mtu;
385 if (slave->hard_header_len > LL_MAX_HEADER)
386 return -EINVAL;
387
388 /* If all the slaves are BROADCAST, master is BROADCAST
389 If all the slaves are PtP, master is PtP
390 Otherwise, master is NBMA.
391 */
392 if (!(slave->flags&IFF_POINTOPOINT))
393 flags &= ~IFF_POINTOPOINT;
394 if (!(slave->flags&IFF_BROADCAST))
395 flags &= ~IFF_BROADCAST;
396 if (!(slave->flags&IFF_MULTICAST))
397 flags &= ~IFF_MULTICAST;
398 } while ((q = NEXT_SLAVE(q)) != m->slaves);
399
400 m->dev->mtu = mtu;
401 m->dev->flags = (m->dev->flags&~FMASK) | flags;
402 netif_start_queue(m->dev);
403 return 0;
404}
405
406static int teql_master_close(struct net_device *dev)
407{
408 netif_stop_queue(dev);
409 return 0;
410}
411
412static struct rtnl_link_stats64 *teql_master_stats64(struct net_device *dev,
413 struct rtnl_link_stats64 *stats)
414{
415 struct teql_master *m = netdev_priv(dev);
416
417 stats->tx_packets = m->tx_packets;
418 stats->tx_bytes = m->tx_bytes;
419 stats->tx_errors = m->tx_errors;
420 stats->tx_dropped = m->tx_dropped;
421 return stats;
422}
423
424static int teql_master_mtu(struct net_device *dev, int new_mtu)
425{
426 struct teql_master *m = netdev_priv(dev);
427 struct Qdisc *q;
428
429 if (new_mtu < 68)
430 return -EINVAL;
431
432 q = m->slaves;
433 if (q) {
434 do {
435 if (new_mtu > qdisc_dev(q)->mtu)
436 return -EINVAL;
437 } while ((q = NEXT_SLAVE(q)) != m->slaves);
438 }
439
440 dev->mtu = new_mtu;
441 return 0;
442}
443
444static const struct net_device_ops teql_netdev_ops = {
445 .ndo_open = teql_master_open,
446 .ndo_stop = teql_master_close,
447 .ndo_start_xmit = teql_master_xmit,
448 .ndo_get_stats64 = teql_master_stats64,
449 .ndo_change_mtu = teql_master_mtu,
450};
451
452static __init void teql_master_setup(struct net_device *dev)
453{
454 struct teql_master *master = netdev_priv(dev);
455 struct Qdisc_ops *ops = &master->qops;
456
457 master->dev = dev;
458 ops->priv_size = sizeof(struct teql_sched_data);
459
460 ops->enqueue = teql_enqueue;
461 ops->dequeue = teql_dequeue;
462 ops->peek = teql_peek;
463 ops->init = teql_qdisc_init;
464 ops->reset = teql_reset;
465 ops->destroy = teql_destroy;
466 ops->owner = THIS_MODULE;
467
468 dev->netdev_ops = &teql_netdev_ops;
469 dev->type = ARPHRD_VOID;
470 dev->mtu = 1500;
471 dev->tx_queue_len = 100;
472 dev->flags = IFF_NOARP;
473 dev->hard_header_len = LL_MAX_HEADER;
474 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
475}
476
477static LIST_HEAD(master_dev_list);
478static int max_equalizers = 1;
479module_param(max_equalizers, int, 0);
480MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
481
482static int __init teql_init(void)
483{
484 int i;
485 int err = -ENODEV;
486
487 for (i = 0; i < max_equalizers; i++) {
488 struct net_device *dev;
489 struct teql_master *master;
490
491 dev = alloc_netdev(sizeof(struct teql_master),
492 "teql%d", teql_master_setup);
493 if (!dev) {
494 err = -ENOMEM;
495 break;
496 }
497
498 if ((err = register_netdev(dev))) {
499 free_netdev(dev);
500 break;
501 }
502
503 master = netdev_priv(dev);
504
505 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
506 err = register_qdisc(&master->qops);
507
508 if (err) {
509 unregister_netdev(dev);
510 free_netdev(dev);
511 break;
512 }
513
514 list_add_tail(&master->master_list, &master_dev_list);
515 }
516 return i ? 0 : err;
517}
518
519static void __exit teql_exit(void)
520{
521 struct teql_master *master, *nxt;
522
523 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
524
525 list_del(&master->master_list);
526
527 unregister_qdisc(&master->qops);
528 unregister_netdev(master->dev);
529 free_netdev(master->dev);
530 }
531}
532
533module_init(teql_init);
534module_exit(teql_exit);
535
536MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* net/sched/sch_teql.c "True" (or "trivial") link equalizer.
3 *
4 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
5 */
6
7#include <linux/module.h>
8#include <linux/types.h>
9#include <linux/kernel.h>
10#include <linux/slab.h>
11#include <linux/string.h>
12#include <linux/errno.h>
13#include <linux/if_arp.h>
14#include <linux/netdevice.h>
15#include <linux/init.h>
16#include <linux/skbuff.h>
17#include <linux/moduleparam.h>
18#include <net/dst.h>
19#include <net/neighbour.h>
20#include <net/pkt_sched.h>
21
22/*
23 How to setup it.
24 ----------------
25
26 After loading this module you will find a new device teqlN
27 and new qdisc with the same name. To join a slave to the equalizer
28 you should just set this qdisc on a device f.e.
29
30 # tc qdisc add dev eth0 root teql0
31 # tc qdisc add dev eth1 root teql0
32
33 That's all. Full PnP 8)
34
35 Applicability.
36 --------------
37
38 1. Slave devices MUST be active devices, i.e., they must raise the tbusy
39 signal and generate EOI events. If you want to equalize virtual devices
40 like tunnels, use a normal eql device.
41 2. This device puts no limitations on physical slave characteristics
42 f.e. it will equalize 9600baud line and 100Mb ethernet perfectly :-)
43 Certainly, large difference in link speeds will make the resulting
44 eqalized link unusable, because of huge packet reordering.
45 I estimate an upper useful difference as ~10 times.
46 3. If the slave requires address resolution, only protocols using
47 neighbour cache (IPv4/IPv6) will work over the equalized link.
48 Other protocols are still allowed to use the slave device directly,
49 which will not break load balancing, though native slave
50 traffic will have the highest priority. */
51
52struct teql_master {
53 struct Qdisc_ops qops;
54 struct net_device *dev;
55 struct Qdisc *slaves;
56 struct list_head master_list;
57 unsigned long tx_bytes;
58 unsigned long tx_packets;
59 unsigned long tx_errors;
60 unsigned long tx_dropped;
61};
62
63struct teql_sched_data {
64 struct Qdisc *next;
65 struct teql_master *m;
66 struct sk_buff_head q;
67};
68
69#define NEXT_SLAVE(q) (((struct teql_sched_data *)qdisc_priv(q))->next)
70
71#define FMASK (IFF_BROADCAST | IFF_POINTOPOINT)
72
73/* "teql*" qdisc routines */
74
75static int
76teql_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free)
77{
78 struct net_device *dev = qdisc_dev(sch);
79 struct teql_sched_data *q = qdisc_priv(sch);
80
81 if (q->q.qlen < dev->tx_queue_len) {
82 __skb_queue_tail(&q->q, skb);
83 return NET_XMIT_SUCCESS;
84 }
85
86 return qdisc_drop(skb, sch, to_free);
87}
88
89static struct sk_buff *
90teql_dequeue(struct Qdisc *sch)
91{
92 struct teql_sched_data *dat = qdisc_priv(sch);
93 struct netdev_queue *dat_queue;
94 struct sk_buff *skb;
95 struct Qdisc *q;
96
97 skb = __skb_dequeue(&dat->q);
98 dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
99 q = rcu_dereference_bh(dat_queue->qdisc);
100
101 if (skb == NULL) {
102 struct net_device *m = qdisc_dev(q);
103 if (m) {
104 dat->m->slaves = sch;
105 netif_wake_queue(m);
106 }
107 } else {
108 qdisc_bstats_update(sch, skb);
109 }
110 sch->q.qlen = dat->q.qlen + q->q.qlen;
111 return skb;
112}
113
114static struct sk_buff *
115teql_peek(struct Qdisc *sch)
116{
117 /* teql is meant to be used as root qdisc */
118 return NULL;
119}
120
121static void
122teql_reset(struct Qdisc *sch)
123{
124 struct teql_sched_data *dat = qdisc_priv(sch);
125
126 skb_queue_purge(&dat->q);
127 sch->q.qlen = 0;
128}
129
130static void
131teql_destroy(struct Qdisc *sch)
132{
133 struct Qdisc *q, *prev;
134 struct teql_sched_data *dat = qdisc_priv(sch);
135 struct teql_master *master = dat->m;
136
137 if (!master)
138 return;
139
140 prev = master->slaves;
141 if (prev) {
142 do {
143 q = NEXT_SLAVE(prev);
144 if (q == sch) {
145 NEXT_SLAVE(prev) = NEXT_SLAVE(q);
146 if (q == master->slaves) {
147 master->slaves = NEXT_SLAVE(q);
148 if (q == master->slaves) {
149 struct netdev_queue *txq;
150 spinlock_t *root_lock;
151
152 txq = netdev_get_tx_queue(master->dev, 0);
153 master->slaves = NULL;
154
155 root_lock = qdisc_root_sleeping_lock(rtnl_dereference(txq->qdisc));
156 spin_lock_bh(root_lock);
157 qdisc_reset(rtnl_dereference(txq->qdisc));
158 spin_unlock_bh(root_lock);
159 }
160 }
161 skb_queue_purge(&dat->q);
162 break;
163 }
164
165 } while ((prev = q) != master->slaves);
166 }
167}
168
169static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt,
170 struct netlink_ext_ack *extack)
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(skb_protocol(skb, false)),
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 void 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}
414
415static int teql_master_mtu(struct net_device *dev, int new_mtu)
416{
417 struct teql_master *m = netdev_priv(dev);
418 struct Qdisc *q;
419
420 q = m->slaves;
421 if (q) {
422 do {
423 if (new_mtu > qdisc_dev(q)->mtu)
424 return -EINVAL;
425 } while ((q = NEXT_SLAVE(q)) != m->slaves);
426 }
427
428 dev->mtu = new_mtu;
429 return 0;
430}
431
432static const struct net_device_ops teql_netdev_ops = {
433 .ndo_open = teql_master_open,
434 .ndo_stop = teql_master_close,
435 .ndo_start_xmit = teql_master_xmit,
436 .ndo_get_stats64 = teql_master_stats64,
437 .ndo_change_mtu = teql_master_mtu,
438};
439
440static __init void teql_master_setup(struct net_device *dev)
441{
442 struct teql_master *master = netdev_priv(dev);
443 struct Qdisc_ops *ops = &master->qops;
444
445 master->dev = dev;
446 ops->priv_size = sizeof(struct teql_sched_data);
447
448 ops->enqueue = teql_enqueue;
449 ops->dequeue = teql_dequeue;
450 ops->peek = teql_peek;
451 ops->init = teql_qdisc_init;
452 ops->reset = teql_reset;
453 ops->destroy = teql_destroy;
454 ops->owner = THIS_MODULE;
455
456 dev->netdev_ops = &teql_netdev_ops;
457 dev->type = ARPHRD_VOID;
458 dev->mtu = 1500;
459 dev->min_mtu = 68;
460 dev->max_mtu = 65535;
461 dev->tx_queue_len = 100;
462 dev->flags = IFF_NOARP;
463 dev->hard_header_len = LL_MAX_HEADER;
464 netif_keep_dst(dev);
465}
466
467static LIST_HEAD(master_dev_list);
468static int max_equalizers = 1;
469module_param(max_equalizers, int, 0);
470MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
471
472static int __init teql_init(void)
473{
474 int i;
475 int err = -ENODEV;
476
477 for (i = 0; i < max_equalizers; i++) {
478 struct net_device *dev;
479 struct teql_master *master;
480
481 dev = alloc_netdev(sizeof(struct teql_master), "teql%d",
482 NET_NAME_UNKNOWN, teql_master_setup);
483 if (!dev) {
484 err = -ENOMEM;
485 break;
486 }
487
488 if ((err = register_netdev(dev))) {
489 free_netdev(dev);
490 break;
491 }
492
493 master = netdev_priv(dev);
494
495 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
496 err = register_qdisc(&master->qops);
497
498 if (err) {
499 unregister_netdev(dev);
500 free_netdev(dev);
501 break;
502 }
503
504 list_add_tail(&master->master_list, &master_dev_list);
505 }
506 return i ? 0 : err;
507}
508
509static void __exit teql_exit(void)
510{
511 struct teql_master *master, *nxt;
512
513 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
514
515 list_del(&master->master_list);
516
517 unregister_qdisc(&master->qops);
518 unregister_netdev(master->dev);
519 free_netdev(master->dev);
520 }
521}
522
523module_init(teql_init);
524module_exit(teql_exit);
525
526MODULE_LICENSE("GPL");