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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 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 kfree_skb(skb);
92 sch->qstats.drops++;
93 return NET_XMIT_DROP;
94}
95
96static struct sk_buff *
97teql_dequeue(struct Qdisc *sch)
98{
99 struct teql_sched_data *dat = qdisc_priv(sch);
100 struct netdev_queue *dat_queue;
101 struct sk_buff *skb;
102
103 skb = __skb_dequeue(&dat->q);
104 dat_queue = netdev_get_tx_queue(dat->m->dev, 0);
105 if (skb == NULL) {
106 struct net_device *m = qdisc_dev(dat_queue->qdisc);
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 + dat_queue->qdisc->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 inline void
126teql_neigh_release(struct neighbour *n)
127{
128 if (n)
129 neigh_release(n);
130}
131
132static void
133teql_reset(struct Qdisc *sch)
134{
135 struct teql_sched_data *dat = qdisc_priv(sch);
136
137 skb_queue_purge(&dat->q);
138 sch->q.qlen = 0;
139 teql_neigh_release(xchg(&dat->ncache, NULL));
140}
141
142static void
143teql_destroy(struct Qdisc *sch)
144{
145 struct Qdisc *q, *prev;
146 struct teql_sched_data *dat = qdisc_priv(sch);
147 struct teql_master *master = dat->m;
148
149 prev = master->slaves;
150 if (prev) {
151 do {
152 q = NEXT_SLAVE(prev);
153 if (q == sch) {
154 NEXT_SLAVE(prev) = NEXT_SLAVE(q);
155 if (q == master->slaves) {
156 master->slaves = NEXT_SLAVE(q);
157 if (q == master->slaves) {
158 struct netdev_queue *txq;
159 spinlock_t *root_lock;
160
161 txq = netdev_get_tx_queue(master->dev, 0);
162 master->slaves = NULL;
163
164 root_lock = qdisc_root_sleeping_lock(txq->qdisc);
165 spin_lock_bh(root_lock);
166 qdisc_reset(txq->qdisc);
167 spin_unlock_bh(root_lock);
168 }
169 }
170 skb_queue_purge(&dat->q);
171 teql_neigh_release(xchg(&dat->ncache, NULL));
172 break;
173 }
174
175 } while ((prev = q) != master->slaves);
176 }
177}
178
179static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt)
180{
181 struct net_device *dev = qdisc_dev(sch);
182 struct teql_master *m = (struct teql_master *)sch->ops;
183 struct teql_sched_data *q = qdisc_priv(sch);
184
185 if (dev->hard_header_len > m->dev->hard_header_len)
186 return -EINVAL;
187
188 if (m->dev == dev)
189 return -ELOOP;
190
191 q->m = m;
192
193 skb_queue_head_init(&q->q);
194
195 if (m->slaves) {
196 if (m->dev->flags & IFF_UP) {
197 if ((m->dev->flags & IFF_POINTOPOINT &&
198 !(dev->flags & IFF_POINTOPOINT)) ||
199 (m->dev->flags & IFF_BROADCAST &&
200 !(dev->flags & IFF_BROADCAST)) ||
201 (m->dev->flags & IFF_MULTICAST &&
202 !(dev->flags & IFF_MULTICAST)) ||
203 dev->mtu < m->dev->mtu)
204 return -EINVAL;
205 } else {
206 if (!(dev->flags&IFF_POINTOPOINT))
207 m->dev->flags &= ~IFF_POINTOPOINT;
208 if (!(dev->flags&IFF_BROADCAST))
209 m->dev->flags &= ~IFF_BROADCAST;
210 if (!(dev->flags&IFF_MULTICAST))
211 m->dev->flags &= ~IFF_MULTICAST;
212 if (dev->mtu < m->dev->mtu)
213 m->dev->mtu = dev->mtu;
214 }
215 q->next = NEXT_SLAVE(m->slaves);
216 NEXT_SLAVE(m->slaves) = sch;
217 } else {
218 q->next = sch;
219 m->slaves = sch;
220 m->dev->mtu = dev->mtu;
221 m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
222 }
223 return 0;
224}
225
226
227static int
228__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res, struct net_device *dev)
229{
230 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, 0);
231 struct teql_sched_data *q = qdisc_priv(dev_queue->qdisc);
232 struct neighbour *mn = dst_get_neighbour(skb_dst(skb));
233 struct neighbour *n = q->ncache;
234
235 if (mn->tbl == NULL)
236 return -EINVAL;
237 if (n && n->tbl == mn->tbl &&
238 memcmp(n->primary_key, mn->primary_key, mn->tbl->key_len) == 0) {
239 atomic_inc(&n->refcnt);
240 } else {
241 n = __neigh_lookup_errno(mn->tbl, mn->primary_key, dev);
242 if (IS_ERR(n))
243 return PTR_ERR(n);
244 }
245 if (neigh_event_send(n, skb_res) == 0) {
246 int err;
247 char haddr[MAX_ADDR_LEN];
248
249 neigh_ha_snapshot(haddr, n, dev);
250 err = dev_hard_header(skb, dev, ntohs(skb->protocol), haddr,
251 NULL, skb->len);
252
253 if (err < 0) {
254 neigh_release(n);
255 return -EINVAL;
256 }
257 teql_neigh_release(xchg(&q->ncache, n));
258 return 0;
259 }
260 neigh_release(n);
261 return (skb_res == NULL) ? -EAGAIN : 1;
262}
263
264static inline int teql_resolve(struct sk_buff *skb,
265 struct sk_buff *skb_res, struct net_device *dev)
266{
267 struct netdev_queue *txq = netdev_get_tx_queue(dev, 0);
268 if (txq->qdisc == &noop_qdisc)
269 return -ENODEV;
270
271 if (dev->header_ops == NULL ||
272 skb_dst(skb) == NULL ||
273 dst_get_neighbour(skb_dst(skb)) == NULL)
274 return 0;
275 return __teql_resolve(skb, skb_res, dev);
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 const struct net_device_ops *slave_ops = slave->netdev_ops;
301
302 if (slave_txq->qdisc_sleeping != q)
303 continue;
304 if (__netif_subqueue_stopped(slave, subq) ||
305 !netif_running(slave)) {
306 busy = 1;
307 continue;
308 }
309
310 switch (teql_resolve(skb, skb_res, slave)) {
311 case 0:
312 if (__netif_tx_trylock(slave_txq)) {
313 unsigned int length = qdisc_pkt_len(skb);
314
315 if (!netif_tx_queue_frozen_or_stopped(slave_txq) &&
316 slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
317 txq_trans_update(slave_txq);
318 __netif_tx_unlock(slave_txq);
319 master->slaves = NEXT_SLAVE(q);
320 netif_wake_queue(dev);
321 master->tx_packets++;
322 master->tx_bytes += length;
323 return NETDEV_TX_OK;
324 }
325 __netif_tx_unlock(slave_txq);
326 }
327 if (netif_queue_stopped(dev))
328 busy = 1;
329 break;
330 case 1:
331 master->slaves = NEXT_SLAVE(q);
332 return NETDEV_TX_OK;
333 default:
334 nores = 1;
335 break;
336 }
337 __skb_pull(skb, skb_network_offset(skb));
338 } while ((q = NEXT_SLAVE(q)) != start);
339
340 if (nores && skb_res == NULL) {
341 skb_res = skb;
342 goto restart;
343 }
344
345 if (busy) {
346 netif_stop_queue(dev);
347 return NETDEV_TX_BUSY;
348 }
349 master->tx_errors++;
350
351drop:
352 master->tx_dropped++;
353 dev_kfree_skb(skb);
354 return NETDEV_TX_OK;
355}
356
357static int teql_master_open(struct net_device *dev)
358{
359 struct Qdisc *q;
360 struct teql_master *m = netdev_priv(dev);
361 int mtu = 0xFFFE;
362 unsigned int flags = IFF_NOARP | IFF_MULTICAST;
363
364 if (m->slaves == NULL)
365 return -EUNATCH;
366
367 flags = FMASK;
368
369 q = m->slaves;
370 do {
371 struct net_device *slave = qdisc_dev(q);
372
373 if (slave == NULL)
374 return -EUNATCH;
375
376 if (slave->mtu < mtu)
377 mtu = slave->mtu;
378 if (slave->hard_header_len > LL_MAX_HEADER)
379 return -EINVAL;
380
381 /* If all the slaves are BROADCAST, master is BROADCAST
382 If all the slaves are PtP, master is PtP
383 Otherwise, master is NBMA.
384 */
385 if (!(slave->flags&IFF_POINTOPOINT))
386 flags &= ~IFF_POINTOPOINT;
387 if (!(slave->flags&IFF_BROADCAST))
388 flags &= ~IFF_BROADCAST;
389 if (!(slave->flags&IFF_MULTICAST))
390 flags &= ~IFF_MULTICAST;
391 } while ((q = NEXT_SLAVE(q)) != m->slaves);
392
393 m->dev->mtu = mtu;
394 m->dev->flags = (m->dev->flags&~FMASK) | flags;
395 netif_start_queue(m->dev);
396 return 0;
397}
398
399static int teql_master_close(struct net_device *dev)
400{
401 netif_stop_queue(dev);
402 return 0;
403}
404
405static struct rtnl_link_stats64 *teql_master_stats64(struct net_device *dev,
406 struct rtnl_link_stats64 *stats)
407{
408 struct teql_master *m = netdev_priv(dev);
409
410 stats->tx_packets = m->tx_packets;
411 stats->tx_bytes = m->tx_bytes;
412 stats->tx_errors = m->tx_errors;
413 stats->tx_dropped = m->tx_dropped;
414 return stats;
415}
416
417static int teql_master_mtu(struct net_device *dev, int new_mtu)
418{
419 struct teql_master *m = netdev_priv(dev);
420 struct Qdisc *q;
421
422 if (new_mtu < 68)
423 return -EINVAL;
424
425 q = m->slaves;
426 if (q) {
427 do {
428 if (new_mtu > qdisc_dev(q)->mtu)
429 return -EINVAL;
430 } while ((q = NEXT_SLAVE(q)) != m->slaves);
431 }
432
433 dev->mtu = new_mtu;
434 return 0;
435}
436
437static const struct net_device_ops teql_netdev_ops = {
438 .ndo_open = teql_master_open,
439 .ndo_stop = teql_master_close,
440 .ndo_start_xmit = teql_master_xmit,
441 .ndo_get_stats64 = teql_master_stats64,
442 .ndo_change_mtu = teql_master_mtu,
443};
444
445static __init void teql_master_setup(struct net_device *dev)
446{
447 struct teql_master *master = netdev_priv(dev);
448 struct Qdisc_ops *ops = &master->qops;
449
450 master->dev = dev;
451 ops->priv_size = sizeof(struct teql_sched_data);
452
453 ops->enqueue = teql_enqueue;
454 ops->dequeue = teql_dequeue;
455 ops->peek = teql_peek;
456 ops->init = teql_qdisc_init;
457 ops->reset = teql_reset;
458 ops->destroy = teql_destroy;
459 ops->owner = THIS_MODULE;
460
461 dev->netdev_ops = &teql_netdev_ops;
462 dev->type = ARPHRD_VOID;
463 dev->mtu = 1500;
464 dev->tx_queue_len = 100;
465 dev->flags = IFF_NOARP;
466 dev->hard_header_len = LL_MAX_HEADER;
467 dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
468}
469
470static LIST_HEAD(master_dev_list);
471static int max_equalizers = 1;
472module_param(max_equalizers, int, 0);
473MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
474
475static int __init teql_init(void)
476{
477 int i;
478 int err = -ENODEV;
479
480 for (i = 0; i < max_equalizers; i++) {
481 struct net_device *dev;
482 struct teql_master *master;
483
484 dev = alloc_netdev(sizeof(struct teql_master),
485 "teql%d", teql_master_setup);
486 if (!dev) {
487 err = -ENOMEM;
488 break;
489 }
490
491 if ((err = register_netdev(dev))) {
492 free_netdev(dev);
493 break;
494 }
495
496 master = netdev_priv(dev);
497
498 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
499 err = register_qdisc(&master->qops);
500
501 if (err) {
502 unregister_netdev(dev);
503 free_netdev(dev);
504 break;
505 }
506
507 list_add_tail(&master->master_list, &master_dev_list);
508 }
509 return i ? 0 : err;
510}
511
512static void __exit teql_exit(void)
513{
514 struct teql_master *master, *nxt;
515
516 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
517
518 list_del(&master->master_list);
519
520 unregister_qdisc(&master->qops);
521 unregister_netdev(master->dev);
522 free_netdev(master->dev);
523 }
524}
525
526module_init(teql_init);
527module_exit(teql_exit);
528
529MODULE_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 prev = master->slaves;
138 if (prev) {
139 do {
140 q = NEXT_SLAVE(prev);
141 if (q == sch) {
142 NEXT_SLAVE(prev) = NEXT_SLAVE(q);
143 if (q == master->slaves) {
144 master->slaves = NEXT_SLAVE(q);
145 if (q == master->slaves) {
146 struct netdev_queue *txq;
147 spinlock_t *root_lock;
148
149 txq = netdev_get_tx_queue(master->dev, 0);
150 master->slaves = NULL;
151
152 root_lock = qdisc_root_sleeping_lock(rtnl_dereference(txq->qdisc));
153 spin_lock_bh(root_lock);
154 qdisc_reset(rtnl_dereference(txq->qdisc));
155 spin_unlock_bh(root_lock);
156 }
157 }
158 skb_queue_purge(&dat->q);
159 break;
160 }
161
162 } while ((prev = q) != master->slaves);
163 }
164}
165
166static int teql_qdisc_init(struct Qdisc *sch, struct nlattr *opt,
167 struct netlink_ext_ack *extack)
168{
169 struct net_device *dev = qdisc_dev(sch);
170 struct teql_master *m = (struct teql_master *)sch->ops;
171 struct teql_sched_data *q = qdisc_priv(sch);
172
173 if (dev->hard_header_len > m->dev->hard_header_len)
174 return -EINVAL;
175
176 if (m->dev == dev)
177 return -ELOOP;
178
179 q->m = m;
180
181 skb_queue_head_init(&q->q);
182
183 if (m->slaves) {
184 if (m->dev->flags & IFF_UP) {
185 if ((m->dev->flags & IFF_POINTOPOINT &&
186 !(dev->flags & IFF_POINTOPOINT)) ||
187 (m->dev->flags & IFF_BROADCAST &&
188 !(dev->flags & IFF_BROADCAST)) ||
189 (m->dev->flags & IFF_MULTICAST &&
190 !(dev->flags & IFF_MULTICAST)) ||
191 dev->mtu < m->dev->mtu)
192 return -EINVAL;
193 } else {
194 if (!(dev->flags&IFF_POINTOPOINT))
195 m->dev->flags &= ~IFF_POINTOPOINT;
196 if (!(dev->flags&IFF_BROADCAST))
197 m->dev->flags &= ~IFF_BROADCAST;
198 if (!(dev->flags&IFF_MULTICAST))
199 m->dev->flags &= ~IFF_MULTICAST;
200 if (dev->mtu < m->dev->mtu)
201 m->dev->mtu = dev->mtu;
202 }
203 q->next = NEXT_SLAVE(m->slaves);
204 NEXT_SLAVE(m->slaves) = sch;
205 } else {
206 q->next = sch;
207 m->slaves = sch;
208 m->dev->mtu = dev->mtu;
209 m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
210 }
211 return 0;
212}
213
214
215static int
216__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
217 struct net_device *dev, struct netdev_queue *txq,
218 struct dst_entry *dst)
219{
220 struct neighbour *n;
221 int err = 0;
222
223 n = dst_neigh_lookup_skb(dst, skb);
224 if (!n)
225 return -ENOENT;
226
227 if (dst->dev != dev) {
228 struct neighbour *mn;
229
230 mn = __neigh_lookup_errno(n->tbl, n->primary_key, dev);
231 neigh_release(n);
232 if (IS_ERR(mn))
233 return PTR_ERR(mn);
234 n = mn;
235 }
236
237 if (neigh_event_send(n, skb_res) == 0) {
238 int err;
239 char haddr[MAX_ADDR_LEN];
240
241 neigh_ha_snapshot(haddr, n, dev);
242 err = dev_hard_header(skb, dev, ntohs(tc_skb_protocol(skb)),
243 haddr, NULL, skb->len);
244
245 if (err < 0)
246 err = -EINVAL;
247 } else {
248 err = (skb_res == NULL) ? -EAGAIN : 1;
249 }
250 neigh_release(n);
251 return err;
252}
253
254static inline int teql_resolve(struct sk_buff *skb,
255 struct sk_buff *skb_res,
256 struct net_device *dev,
257 struct netdev_queue *txq)
258{
259 struct dst_entry *dst = skb_dst(skb);
260 int res;
261
262 if (rcu_access_pointer(txq->qdisc) == &noop_qdisc)
263 return -ENODEV;
264
265 if (!dev->header_ops || !dst)
266 return 0;
267
268 rcu_read_lock();
269 res = __teql_resolve(skb, skb_res, dev, txq, dst);
270 rcu_read_unlock();
271
272 return res;
273}
274
275static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
276{
277 struct teql_master *master = netdev_priv(dev);
278 struct Qdisc *start, *q;
279 int busy;
280 int nores;
281 int subq = skb_get_queue_mapping(skb);
282 struct sk_buff *skb_res = NULL;
283
284 start = master->slaves;
285
286restart:
287 nores = 0;
288 busy = 0;
289
290 q = start;
291 if (!q)
292 goto drop;
293
294 do {
295 struct net_device *slave = qdisc_dev(q);
296 struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
297
298 if (slave_txq->qdisc_sleeping != q)
299 continue;
300 if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
301 !netif_running(slave)) {
302 busy = 1;
303 continue;
304 }
305
306 switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
307 case 0:
308 if (__netif_tx_trylock(slave_txq)) {
309 unsigned int length = qdisc_pkt_len(skb);
310
311 if (!netif_xmit_frozen_or_stopped(slave_txq) &&
312 netdev_start_xmit(skb, slave, slave_txq, false) ==
313 NETDEV_TX_OK) {
314 __netif_tx_unlock(slave_txq);
315 master->slaves = NEXT_SLAVE(q);
316 netif_wake_queue(dev);
317 master->tx_packets++;
318 master->tx_bytes += length;
319 return NETDEV_TX_OK;
320 }
321 __netif_tx_unlock(slave_txq);
322 }
323 if (netif_xmit_stopped(netdev_get_tx_queue(dev, 0)))
324 busy = 1;
325 break;
326 case 1:
327 master->slaves = NEXT_SLAVE(q);
328 return NETDEV_TX_OK;
329 default:
330 nores = 1;
331 break;
332 }
333 __skb_pull(skb, skb_network_offset(skb));
334 } while ((q = NEXT_SLAVE(q)) != start);
335
336 if (nores && skb_res == NULL) {
337 skb_res = skb;
338 goto restart;
339 }
340
341 if (busy) {
342 netif_stop_queue(dev);
343 return NETDEV_TX_BUSY;
344 }
345 master->tx_errors++;
346
347drop:
348 master->tx_dropped++;
349 dev_kfree_skb(skb);
350 return NETDEV_TX_OK;
351}
352
353static int teql_master_open(struct net_device *dev)
354{
355 struct Qdisc *q;
356 struct teql_master *m = netdev_priv(dev);
357 int mtu = 0xFFFE;
358 unsigned int flags = IFF_NOARP | IFF_MULTICAST;
359
360 if (m->slaves == NULL)
361 return -EUNATCH;
362
363 flags = FMASK;
364
365 q = m->slaves;
366 do {
367 struct net_device *slave = qdisc_dev(q);
368
369 if (slave == NULL)
370 return -EUNATCH;
371
372 if (slave->mtu < mtu)
373 mtu = slave->mtu;
374 if (slave->hard_header_len > LL_MAX_HEADER)
375 return -EINVAL;
376
377 /* If all the slaves are BROADCAST, master is BROADCAST
378 If all the slaves are PtP, master is PtP
379 Otherwise, master is NBMA.
380 */
381 if (!(slave->flags&IFF_POINTOPOINT))
382 flags &= ~IFF_POINTOPOINT;
383 if (!(slave->flags&IFF_BROADCAST))
384 flags &= ~IFF_BROADCAST;
385 if (!(slave->flags&IFF_MULTICAST))
386 flags &= ~IFF_MULTICAST;
387 } while ((q = NEXT_SLAVE(q)) != m->slaves);
388
389 m->dev->mtu = mtu;
390 m->dev->flags = (m->dev->flags&~FMASK) | flags;
391 netif_start_queue(m->dev);
392 return 0;
393}
394
395static int teql_master_close(struct net_device *dev)
396{
397 netif_stop_queue(dev);
398 return 0;
399}
400
401static void teql_master_stats64(struct net_device *dev,
402 struct rtnl_link_stats64 *stats)
403{
404 struct teql_master *m = netdev_priv(dev);
405
406 stats->tx_packets = m->tx_packets;
407 stats->tx_bytes = m->tx_bytes;
408 stats->tx_errors = m->tx_errors;
409 stats->tx_dropped = m->tx_dropped;
410}
411
412static int teql_master_mtu(struct net_device *dev, int new_mtu)
413{
414 struct teql_master *m = netdev_priv(dev);
415 struct Qdisc *q;
416
417 q = m->slaves;
418 if (q) {
419 do {
420 if (new_mtu > qdisc_dev(q)->mtu)
421 return -EINVAL;
422 } while ((q = NEXT_SLAVE(q)) != m->slaves);
423 }
424
425 dev->mtu = new_mtu;
426 return 0;
427}
428
429static const struct net_device_ops teql_netdev_ops = {
430 .ndo_open = teql_master_open,
431 .ndo_stop = teql_master_close,
432 .ndo_start_xmit = teql_master_xmit,
433 .ndo_get_stats64 = teql_master_stats64,
434 .ndo_change_mtu = teql_master_mtu,
435};
436
437static __init void teql_master_setup(struct net_device *dev)
438{
439 struct teql_master *master = netdev_priv(dev);
440 struct Qdisc_ops *ops = &master->qops;
441
442 master->dev = dev;
443 ops->priv_size = sizeof(struct teql_sched_data);
444
445 ops->enqueue = teql_enqueue;
446 ops->dequeue = teql_dequeue;
447 ops->peek = teql_peek;
448 ops->init = teql_qdisc_init;
449 ops->reset = teql_reset;
450 ops->destroy = teql_destroy;
451 ops->owner = THIS_MODULE;
452
453 dev->netdev_ops = &teql_netdev_ops;
454 dev->type = ARPHRD_VOID;
455 dev->mtu = 1500;
456 dev->min_mtu = 68;
457 dev->max_mtu = 65535;
458 dev->tx_queue_len = 100;
459 dev->flags = IFF_NOARP;
460 dev->hard_header_len = LL_MAX_HEADER;
461 netif_keep_dst(dev);
462}
463
464static LIST_HEAD(master_dev_list);
465static int max_equalizers = 1;
466module_param(max_equalizers, int, 0);
467MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
468
469static int __init teql_init(void)
470{
471 int i;
472 int err = -ENODEV;
473
474 for (i = 0; i < max_equalizers; i++) {
475 struct net_device *dev;
476 struct teql_master *master;
477
478 dev = alloc_netdev(sizeof(struct teql_master), "teql%d",
479 NET_NAME_UNKNOWN, teql_master_setup);
480 if (!dev) {
481 err = -ENOMEM;
482 break;
483 }
484
485 if ((err = register_netdev(dev))) {
486 free_netdev(dev);
487 break;
488 }
489
490 master = netdev_priv(dev);
491
492 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
493 err = register_qdisc(&master->qops);
494
495 if (err) {
496 unregister_netdev(dev);
497 free_netdev(dev);
498 break;
499 }
500
501 list_add_tail(&master->master_list, &master_dev_list);
502 }
503 return i ? 0 : err;
504}
505
506static void __exit teql_exit(void)
507{
508 struct teql_master *master, *nxt;
509
510 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
511
512 list_del(&master->master_list);
513
514 unregister_qdisc(&master->qops);
515 unregister_netdev(master->dev);
516 free_netdev(master->dev);
517 }
518}
519
520module_init(teql_init);
521module_exit(teql_exit);
522
523MODULE_LICENSE("GPL");