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 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/* 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, struct sk_buff **to_free)
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, to_free);
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 struct netlink_ext_ack *extack)
172{
173 struct net_device *dev = qdisc_dev(sch);
174 struct teql_master *m = (struct teql_master *)sch->ops;
175 struct teql_sched_data *q = qdisc_priv(sch);
176
177 if (dev->hard_header_len > m->dev->hard_header_len)
178 return -EINVAL;
179
180 if (m->dev == dev)
181 return -ELOOP;
182
183 q->m = m;
184
185 skb_queue_head_init(&q->q);
186
187 if (m->slaves) {
188 if (m->dev->flags & IFF_UP) {
189 if ((m->dev->flags & IFF_POINTOPOINT &&
190 !(dev->flags & IFF_POINTOPOINT)) ||
191 (m->dev->flags & IFF_BROADCAST &&
192 !(dev->flags & IFF_BROADCAST)) ||
193 (m->dev->flags & IFF_MULTICAST &&
194 !(dev->flags & IFF_MULTICAST)) ||
195 dev->mtu < m->dev->mtu)
196 return -EINVAL;
197 } else {
198 if (!(dev->flags&IFF_POINTOPOINT))
199 m->dev->flags &= ~IFF_POINTOPOINT;
200 if (!(dev->flags&IFF_BROADCAST))
201 m->dev->flags &= ~IFF_BROADCAST;
202 if (!(dev->flags&IFF_MULTICAST))
203 m->dev->flags &= ~IFF_MULTICAST;
204 if (dev->mtu < m->dev->mtu)
205 m->dev->mtu = dev->mtu;
206 }
207 q->next = NEXT_SLAVE(m->slaves);
208 NEXT_SLAVE(m->slaves) = sch;
209 } else {
210 q->next = sch;
211 m->slaves = sch;
212 m->dev->mtu = dev->mtu;
213 m->dev->flags = (m->dev->flags&~FMASK)|(dev->flags&FMASK);
214 }
215 return 0;
216}
217
218
219static int
220__teql_resolve(struct sk_buff *skb, struct sk_buff *skb_res,
221 struct net_device *dev, struct netdev_queue *txq,
222 struct dst_entry *dst)
223{
224 struct neighbour *n;
225 int err = 0;
226
227 n = dst_neigh_lookup_skb(dst, skb);
228 if (!n)
229 return -ENOENT;
230
231 if (dst->dev != dev) {
232 struct neighbour *mn;
233
234 mn = __neigh_lookup_errno(n->tbl, n->primary_key, dev);
235 neigh_release(n);
236 if (IS_ERR(mn))
237 return PTR_ERR(mn);
238 n = mn;
239 }
240
241 if (neigh_event_send(n, skb_res) == 0) {
242 int err;
243 char haddr[MAX_ADDR_LEN];
244
245 neigh_ha_snapshot(haddr, n, dev);
246 err = dev_hard_header(skb, dev, ntohs(tc_skb_protocol(skb)),
247 haddr, NULL, skb->len);
248
249 if (err < 0)
250 err = -EINVAL;
251 } else {
252 err = (skb_res == NULL) ? -EAGAIN : 1;
253 }
254 neigh_release(n);
255 return err;
256}
257
258static inline int teql_resolve(struct sk_buff *skb,
259 struct sk_buff *skb_res,
260 struct net_device *dev,
261 struct netdev_queue *txq)
262{
263 struct dst_entry *dst = skb_dst(skb);
264 int res;
265
266 if (rcu_access_pointer(txq->qdisc) == &noop_qdisc)
267 return -ENODEV;
268
269 if (!dev->header_ops || !dst)
270 return 0;
271
272 rcu_read_lock();
273 res = __teql_resolve(skb, skb_res, dev, txq, dst);
274 rcu_read_unlock();
275
276 return res;
277}
278
279static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
280{
281 struct teql_master *master = netdev_priv(dev);
282 struct Qdisc *start, *q;
283 int busy;
284 int nores;
285 int subq = skb_get_queue_mapping(skb);
286 struct sk_buff *skb_res = NULL;
287
288 start = master->slaves;
289
290restart:
291 nores = 0;
292 busy = 0;
293
294 q = start;
295 if (!q)
296 goto drop;
297
298 do {
299 struct net_device *slave = qdisc_dev(q);
300 struct netdev_queue *slave_txq = netdev_get_tx_queue(slave, 0);
301
302 if (slave_txq->qdisc_sleeping != q)
303 continue;
304 if (netif_xmit_stopped(netdev_get_tx_queue(slave, subq)) ||
305 !netif_running(slave)) {
306 busy = 1;
307 continue;
308 }
309
310 switch (teql_resolve(skb, skb_res, slave, slave_txq)) {
311 case 0:
312 if (__netif_tx_trylock(slave_txq)) {
313 unsigned int length = qdisc_pkt_len(skb);
314
315 if (!netif_xmit_frozen_or_stopped(slave_txq) &&
316 netdev_start_xmit(skb, slave, slave_txq, false) ==
317 NETDEV_TX_OK) {
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_xmit_stopped(netdev_get_tx_queue(dev, 0)))
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 void 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}
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 q = m->slaves;
422 if (q) {
423 do {
424 if (new_mtu > qdisc_dev(q)->mtu)
425 return -EINVAL;
426 } while ((q = NEXT_SLAVE(q)) != m->slaves);
427 }
428
429 dev->mtu = new_mtu;
430 return 0;
431}
432
433static const struct net_device_ops teql_netdev_ops = {
434 .ndo_open = teql_master_open,
435 .ndo_stop = teql_master_close,
436 .ndo_start_xmit = teql_master_xmit,
437 .ndo_get_stats64 = teql_master_stats64,
438 .ndo_change_mtu = teql_master_mtu,
439};
440
441static __init void teql_master_setup(struct net_device *dev)
442{
443 struct teql_master *master = netdev_priv(dev);
444 struct Qdisc_ops *ops = &master->qops;
445
446 master->dev = dev;
447 ops->priv_size = sizeof(struct teql_sched_data);
448
449 ops->enqueue = teql_enqueue;
450 ops->dequeue = teql_dequeue;
451 ops->peek = teql_peek;
452 ops->init = teql_qdisc_init;
453 ops->reset = teql_reset;
454 ops->destroy = teql_destroy;
455 ops->owner = THIS_MODULE;
456
457 dev->netdev_ops = &teql_netdev_ops;
458 dev->type = ARPHRD_VOID;
459 dev->mtu = 1500;
460 dev->min_mtu = 68;
461 dev->max_mtu = 65535;
462 dev->tx_queue_len = 100;
463 dev->flags = IFF_NOARP;
464 dev->hard_header_len = LL_MAX_HEADER;
465 netif_keep_dst(dev);
466}
467
468static LIST_HEAD(master_dev_list);
469static int max_equalizers = 1;
470module_param(max_equalizers, int, 0);
471MODULE_PARM_DESC(max_equalizers, "Max number of link equalizers");
472
473static int __init teql_init(void)
474{
475 int i;
476 int err = -ENODEV;
477
478 for (i = 0; i < max_equalizers; i++) {
479 struct net_device *dev;
480 struct teql_master *master;
481
482 dev = alloc_netdev(sizeof(struct teql_master), "teql%d",
483 NET_NAME_UNKNOWN, teql_master_setup);
484 if (!dev) {
485 err = -ENOMEM;
486 break;
487 }
488
489 if ((err = register_netdev(dev))) {
490 free_netdev(dev);
491 break;
492 }
493
494 master = netdev_priv(dev);
495
496 strlcpy(master->qops.id, dev->name, IFNAMSIZ);
497 err = register_qdisc(&master->qops);
498
499 if (err) {
500 unregister_netdev(dev);
501 free_netdev(dev);
502 break;
503 }
504
505 list_add_tail(&master->master_list, &master_dev_list);
506 }
507 return i ? 0 : err;
508}
509
510static void __exit teql_exit(void)
511{
512 struct teql_master *master, *nxt;
513
514 list_for_each_entry_safe(master, nxt, &master_dev_list, master_list) {
515
516 list_del(&master->master_list);
517
518 unregister_qdisc(&master->qops);
519 unregister_netdev(master->dev);
520 free_netdev(master->dev);
521 }
522}
523
524module_init(teql_init);
525module_exit(teql_exit);
526
527MODULE_LICENSE("GPL");