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ktest: Search for linux banner for successful reboot
[linux-2.6.git] / net / sched / sch_api.c
blobd84f7e734cd74071144020490862d91c65855ee9
1 /*
2 * net/sched/sch_api.c Packet scheduler API.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 * Fixes:
12 *
13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
16 */
17
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/skbuff.h>
24 #include <linux/init.h>
25 #include <linux/proc_fs.h>
26 #include <linux/seq_file.h>
27 #include <linux/kmod.h>
28 #include <linux/list.h>
29 #include <linux/hrtimer.h>
30 #include <linux/lockdep.h>
31 #include <linux/slab.h>
32
33 #include <net/net_namespace.h>
34 #include <net/sock.h>
35 #include <net/netlink.h>
36 #include <net/pkt_sched.h>
37
38 static int qdisc_notify(struct net *net, struct sk_buff *oskb,
39 struct nlmsghdr *n, u32 clid,
40 struct Qdisc *old, struct Qdisc *new);
41 static int tclass_notify(struct net *net, struct sk_buff *oskb,
42 struct nlmsghdr *n, struct Qdisc *q,
43 unsigned long cl, int event);
44
45 /*
46
47 Short review.
48 -------------
49
50 This file consists of two interrelated parts:
51
52 1. queueing disciplines manager frontend.
53 2. traffic classes manager frontend.
54
55 Generally, queueing discipline ("qdisc") is a black box,
56 which is able to enqueue packets and to dequeue them (when
57 device is ready to send something) in order and at times
58 determined by algorithm hidden in it.
59
60 qdisc's are divided to two categories:
61 - "queues", which have no internal structure visible from outside.
62 - "schedulers", which split all the packets to "traffic classes",
63 using "packet classifiers" (look at cls_api.c)
64
65 In turn, classes may have child qdiscs (as rule, queues)
66 attached to them etc. etc. etc.
67
68 The goal of the routines in this file is to translate
69 information supplied by user in the form of handles
70 to more intelligible for kernel form, to make some sanity
71 checks and part of work, which is common to all qdiscs
72 and to provide rtnetlink notifications.
73
74 All real intelligent work is done inside qdisc modules.
75
76
77
78 Every discipline has two major routines: enqueue and dequeue.
79
80 ---dequeue
81
82 dequeue usually returns a skb to send. It is allowed to return NULL,
83 but it does not mean that queue is empty, it just means that
84 discipline does not want to send anything this time.
85 Queue is really empty if q->q.qlen == 0.
86 For complicated disciplines with multiple queues q->q is not
87 real packet queue, but however q->q.qlen must be valid.
88
89 ---enqueue
90
91 enqueue returns 0, if packet was enqueued successfully.
92 If packet (this one or another one) was dropped, it returns
93 not zero error code.
94 NET_XMIT_DROP - this packet dropped
95 Expected action: do not backoff, but wait until queue will clear.
96 NET_XMIT_CN - probably this packet enqueued, but another one dropped.
97 Expected action: backoff or ignore
98 NET_XMIT_POLICED - dropped by police.
99 Expected action: backoff or error to real-time apps.
100
101 Auxiliary routines:
102
103 ---peek
104
105 like dequeue but without removing a packet from the queue
106
107 ---reset
108
109 returns qdisc to initial state: purge all buffers, clear all
110 timers, counters (except for statistics) etc.
111
112 ---init
113
114 initializes newly created qdisc.
115
116 ---destroy
117
118 destroys resources allocated by init and during lifetime of qdisc.
119
120 ---change
121
122 changes qdisc parameters.
123 */
124
125 /* Protects list of registered TC modules. It is pure SMP lock. */
126 static DEFINE_RWLOCK(qdisc_mod_lock);
127
128
129 /************************************************
130 * Queueing disciplines manipulation. *
131 ************************************************/
132
133
134 /* The list of all installed queueing disciplines. */
135
136 static struct Qdisc_ops *qdisc_base;
137
138 /* Register/uregister queueing discipline */
139
140 int register_qdisc(struct Qdisc_ops *qops)
141 {
142 struct Qdisc_ops *q, **qp;
143 int rc = -EEXIST;
144
145 write_lock(&qdisc_mod_lock);
146 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
147 if (!strcmp(qops->id, q->id))
148 goto out;
149
150 if (qops->enqueue == NULL)
151 qops->enqueue = noop_qdisc_ops.enqueue;
152 if (qops->peek == NULL) {
153 if (qops->dequeue == NULL)
154 qops->peek = noop_qdisc_ops.peek;
155 else
156 goto out_einval;
157 }
158 if (qops->dequeue == NULL)
159 qops->dequeue = noop_qdisc_ops.dequeue;
160
161 if (qops->cl_ops) {
162 const struct Qdisc_class_ops *cops = qops->cl_ops;
163
164 if (!(cops->get && cops->put && cops->walk && cops->leaf))
165 goto out_einval;
166
167 if (cops->tcf_chain && !(cops->bind_tcf && cops->unbind_tcf))
168 goto out_einval;
169 }
170
171 qops->next = NULL;
172 *qp = qops;
173 rc = 0;
174 out:
175 write_unlock(&qdisc_mod_lock);
176 return rc;
177
178 out_einval:
179 rc = -EINVAL;
180 goto out;
181 }
182 EXPORT_SYMBOL(register_qdisc);
183
184 int unregister_qdisc(struct Qdisc_ops *qops)
185 {
186 struct Qdisc_ops *q, **qp;
187 int err = -ENOENT;
188
189 write_lock(&qdisc_mod_lock);
190 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
191 if (q == qops)
192 break;
193 if (q) {
194 *qp = q->next;
195 q->next = NULL;
196 err = 0;
197 }
198 write_unlock(&qdisc_mod_lock);
199 return err;
200 }
201 EXPORT_SYMBOL(unregister_qdisc);
202
203 /* We know handle. Find qdisc among all qdisc's attached to device
204 (root qdisc, all its children, children of children etc.)
205 */
206
207 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
208 {
209 struct Qdisc *q;
210
211 if (!(root->flags & TCQ_F_BUILTIN) &&
212 root->handle == handle)
213 return root;
214
215 list_for_each_entry(q, &root->list, list) {
216 if (q->handle == handle)
217 return q;
218 }
219 return NULL;
220 }
221
222 static void qdisc_list_add(struct Qdisc *q)
223 {
224 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
225 list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list);
226 }
227
228 void qdisc_list_del(struct Qdisc *q)
229 {
230 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
231 list_del(&q->list);
232 }
233 EXPORT_SYMBOL(qdisc_list_del);
234
235 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
236 {
237 struct Qdisc *q;
238
239 q = qdisc_match_from_root(dev->qdisc, handle);
240 if (q)
241 goto out;
242
243 if (dev_ingress_queue(dev))
244 q = qdisc_match_from_root(
245 dev_ingress_queue(dev)->qdisc_sleeping,
246 handle);
247 out:
248 return q;
249 }
250
251 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
252 {
253 unsigned long cl;
254 struct Qdisc *leaf;
255 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
256
257 if (cops == NULL)
258 return NULL;
259 cl = cops->get(p, classid);
260
261 if (cl == 0)
262 return NULL;
263 leaf = cops->leaf(p, cl);
264 cops->put(p, cl);
265 return leaf;
266 }
267
268 /* Find queueing discipline by name */
269
270 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
271 {
272 struct Qdisc_ops *q = NULL;
273
274 if (kind) {
275 read_lock(&qdisc_mod_lock);
276 for (q = qdisc_base; q; q = q->next) {
277 if (nla_strcmp(kind, q->id) == 0) {
278 if (!try_module_get(q->owner))
279 q = NULL;
280 break;
281 }
282 }
283 read_unlock(&qdisc_mod_lock);
284 }
285 return q;
286 }
287
288 static struct qdisc_rate_table *qdisc_rtab_list;
289
290 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
291 {
292 struct qdisc_rate_table *rtab;
293
294 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
295 if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) {
296 rtab->refcnt++;
297 return rtab;
298 }
299 }
300
301 if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
302 nla_len(tab) != TC_RTAB_SIZE)
303 return NULL;
304
305 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
306 if (rtab) {
307 rtab->rate = *r;
308 rtab->refcnt = 1;
309 memcpy(rtab->data, nla_data(tab), 1024);
310 rtab->next = qdisc_rtab_list;
311 qdisc_rtab_list = rtab;
312 }
313 return rtab;
314 }
315 EXPORT_SYMBOL(qdisc_get_rtab);
316
317 void qdisc_put_rtab(struct qdisc_rate_table *tab)
318 {
319 struct qdisc_rate_table *rtab, **rtabp;
320
321 if (!tab || --tab->refcnt)
322 return;
323
324 for (rtabp = &qdisc_rtab_list;
325 (rtab = *rtabp) != NULL;
326 rtabp = &rtab->next) {
327 if (rtab == tab) {
328 *rtabp = rtab->next;
329 kfree(rtab);
330 return;
331 }
332 }
333 }
334 EXPORT_SYMBOL(qdisc_put_rtab);
335
336 static LIST_HEAD(qdisc_stab_list);
337 static DEFINE_SPINLOCK(qdisc_stab_lock);
338
339 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
340 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) },
341 [TCA_STAB_DATA] = { .type = NLA_BINARY },
342 };
343
344 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
345 {
346 struct nlattr *tb[TCA_STAB_MAX + 1];
347 struct qdisc_size_table *stab;
348 struct tc_sizespec *s;
349 unsigned int tsize = 0;
350 u16 *tab = NULL;
351 int err;
352
353 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy);
354 if (err < 0)
355 return ERR_PTR(err);
356 if (!tb[TCA_STAB_BASE])
357 return ERR_PTR(-EINVAL);
358
359 s = nla_data(tb[TCA_STAB_BASE]);
360
361 if (s->tsize > 0) {
362 if (!tb[TCA_STAB_DATA])
363 return ERR_PTR(-EINVAL);
364 tab = nla_data(tb[TCA_STAB_DATA]);
365 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
366 }
367
368 if (tsize != s->tsize || (!tab && tsize > 0))
369 return ERR_PTR(-EINVAL);
370
371 spin_lock(&qdisc_stab_lock);
372
373 list_for_each_entry(stab, &qdisc_stab_list, list) {
374 if (memcmp(&stab->szopts, s, sizeof(*s)))
375 continue;
376 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16)))
377 continue;
378 stab->refcnt++;
379 spin_unlock(&qdisc_stab_lock);
380 return stab;
381 }
382
383 spin_unlock(&qdisc_stab_lock);
384
385 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
386 if (!stab)
387 return ERR_PTR(-ENOMEM);
388
389 stab->refcnt = 1;
390 stab->szopts = *s;
391 if (tsize > 0)
392 memcpy(stab->data, tab, tsize * sizeof(u16));
393
394 spin_lock(&qdisc_stab_lock);
395 list_add_tail(&stab->list, &qdisc_stab_list);
396 spin_unlock(&qdisc_stab_lock);
397
398 return stab;
399 }
400
401 static void stab_kfree_rcu(struct rcu_head *head)
402 {
403 kfree(container_of(head, struct qdisc_size_table, rcu));
404 }
405
406 void qdisc_put_stab(struct qdisc_size_table *tab)
407 {
408 if (!tab)
409 return;
410
411 spin_lock(&qdisc_stab_lock);
412
413 if (--tab->refcnt == 0) {
414 list_del(&tab->list);
415 call_rcu_bh(&tab->rcu, stab_kfree_rcu);
416 }
417
418 spin_unlock(&qdisc_stab_lock);
419 }
420 EXPORT_SYMBOL(qdisc_put_stab);
421
422 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
423 {
424 struct nlattr *nest;
425
426 nest = nla_nest_start(skb, TCA_STAB);
427 if (nest == NULL)
428 goto nla_put_failure;
429 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
430 goto nla_put_failure;
431 nla_nest_end(skb, nest);
432
433 return skb->len;
434
435 nla_put_failure:
436 return -1;
437 }
438
439 void __qdisc_calculate_pkt_len(struct sk_buff *skb, const struct qdisc_size_table *stab)
440 {
441 int pkt_len, slot;
442
443 pkt_len = skb->len + stab->szopts.overhead;
444 if (unlikely(!stab->szopts.tsize))
445 goto out;
446
447 slot = pkt_len + stab->szopts.cell_align;
448 if (unlikely(slot < 0))
449 slot = 0;
450
451 slot >>= stab->szopts.cell_log;
452 if (likely(slot < stab->szopts.tsize))
453 pkt_len = stab->data[slot];
454 else
455 pkt_len = stab->data[stab->szopts.tsize - 1] *
456 (slot / stab->szopts.tsize) +
457 stab->data[slot % stab->szopts.tsize];
458
459 pkt_len <<= stab->szopts.size_log;
460 out:
461 if (unlikely(pkt_len < 1))
462 pkt_len = 1;
463 qdisc_skb_cb(skb)->pkt_len = pkt_len;
464 }
465 EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
466
467 void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc)
468 {
469 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
470 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
471 txt, qdisc->ops->id, qdisc->handle >> 16);
472 qdisc->flags |= TCQ_F_WARN_NONWC;
473 }
474 }
475 EXPORT_SYMBOL(qdisc_warn_nonwc);
476
477 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
478 {
479 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
480 timer);
481
482 qdisc_unthrottled(wd->qdisc);
483 __netif_schedule(qdisc_root(wd->qdisc));
484
485 return HRTIMER_NORESTART;
486 }
487
488 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
489 {
490 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
491 wd->timer.function = qdisc_watchdog;
492 wd->qdisc = qdisc;
493 }
494 EXPORT_SYMBOL(qdisc_watchdog_init);
495
496 void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires)
497 {
498 if (test_bit(__QDISC_STATE_DEACTIVATED,
499 &qdisc_root_sleeping(wd->qdisc)->state))
500 return;
501
502 qdisc_throttled(wd->qdisc);
503
504 hrtimer_start(&wd->timer,
505 ns_to_ktime(PSCHED_TICKS2NS(expires)),
506 HRTIMER_MODE_ABS);
507 }
508 EXPORT_SYMBOL(qdisc_watchdog_schedule);
509
510 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
511 {
512 hrtimer_cancel(&wd->timer);
513 qdisc_unthrottled(wd->qdisc);
514 }
515 EXPORT_SYMBOL(qdisc_watchdog_cancel);
516
517 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
518 {
519 unsigned int size = n * sizeof(struct hlist_head), i;
520 struct hlist_head *h;
521
522 if (size <= PAGE_SIZE)
523 h = kmalloc(size, GFP_KERNEL);
524 else
525 h = (struct hlist_head *)
526 __get_free_pages(GFP_KERNEL, get_order(size));
527
528 if (h != NULL) {
529 for (i = 0; i < n; i++)
530 INIT_HLIST_HEAD(&h[i]);
531 }
532 return h;
533 }
534
535 static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
536 {
537 unsigned int size = n * sizeof(struct hlist_head);
538
539 if (size <= PAGE_SIZE)
540 kfree(h);
541 else
542 free_pages((unsigned long)h, get_order(size));
543 }
544
545 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
546 {
547 struct Qdisc_class_common *cl;
548 struct hlist_node *n, *next;
549 struct hlist_head *nhash, *ohash;
550 unsigned int nsize, nmask, osize;
551 unsigned int i, h;
552
553 /* Rehash when load factor exceeds 0.75 */
554 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
555 return;
556 nsize = clhash->hashsize * 2;
557 nmask = nsize - 1;
558 nhash = qdisc_class_hash_alloc(nsize);
559 if (nhash == NULL)
560 return;
561
562 ohash = clhash->hash;
563 osize = clhash->hashsize;
564
565 sch_tree_lock(sch);
566 for (i = 0; i < osize; i++) {
567 hlist_for_each_entry_safe(cl, n, next, &ohash[i], hnode) {
568 h = qdisc_class_hash(cl->classid, nmask);
569 hlist_add_head(&cl->hnode, &nhash[h]);
570 }
571 }
572 clhash->hash = nhash;
573 clhash->hashsize = nsize;
574 clhash->hashmask = nmask;
575 sch_tree_unlock(sch);
576
577 qdisc_class_hash_free(ohash, osize);
578 }
579 EXPORT_SYMBOL(qdisc_class_hash_grow);
580
581 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
582 {
583 unsigned int size = 4;
584
585 clhash->hash = qdisc_class_hash_alloc(size);
586 if (clhash->hash == NULL)
587 return -ENOMEM;
588 clhash->hashsize = size;
589 clhash->hashmask = size - 1;
590 clhash->hashelems = 0;
591 return 0;
592 }
593 EXPORT_SYMBOL(qdisc_class_hash_init);
594
595 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
596 {
597 qdisc_class_hash_free(clhash->hash, clhash->hashsize);
598 }
599 EXPORT_SYMBOL(qdisc_class_hash_destroy);
600
601 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
602 struct Qdisc_class_common *cl)
603 {
604 unsigned int h;
605
606 INIT_HLIST_NODE(&cl->hnode);
607 h = qdisc_class_hash(cl->classid, clhash->hashmask);
608 hlist_add_head(&cl->hnode, &clhash->hash[h]);
609 clhash->hashelems++;
610 }
611 EXPORT_SYMBOL(qdisc_class_hash_insert);
612
613 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
614 struct Qdisc_class_common *cl)
615 {
616 hlist_del(&cl->hnode);
617 clhash->hashelems--;
618 }
619 EXPORT_SYMBOL(qdisc_class_hash_remove);
620
621 /* Allocate an unique handle from space managed by kernel
622 * Possible range is [8000-FFFF]:0000 (0x8000 values)
623 */
624 static u32 qdisc_alloc_handle(struct net_device *dev)
625 {
626 int i = 0x8000;
627 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
628
629 do {
630 autohandle += TC_H_MAKE(0x10000U, 0);
631 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
632 autohandle = TC_H_MAKE(0x80000000U, 0);
633 if (!qdisc_lookup(dev, autohandle))
634 return autohandle;
635 cond_resched();
636 } while (--i > 0);
637
638 return 0;
639 }
640
641 void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
642 {
643 const struct Qdisc_class_ops *cops;
644 unsigned long cl;
645 u32 parentid;
646
647 if (n == 0)
648 return;
649 while ((parentid = sch->parent)) {
650 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
651 return;
652
653 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
654 if (sch == NULL) {
655 WARN_ON(parentid != TC_H_ROOT);
656 return;
657 }
658 cops = sch->ops->cl_ops;
659 if (cops->qlen_notify) {
660 cl = cops->get(sch, parentid);
661 cops->qlen_notify(sch, cl);
662 cops->put(sch, cl);
663 }
664 sch->q.qlen -= n;
665 }
666 }
667 EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
668
669 static void notify_and_destroy(struct net *net, struct sk_buff *skb,
670 struct nlmsghdr *n, u32 clid,
671 struct Qdisc *old, struct Qdisc *new)
672 {
673 if (new || old)
674 qdisc_notify(net, skb, n, clid, old, new);
675
676 if (old)
677 qdisc_destroy(old);
678 }
679
680 /* Graft qdisc "new" to class "classid" of qdisc "parent" or
681 * to device "dev".
682 *
683 * When appropriate send a netlink notification using 'skb'
684 * and "n".
685 *
686 * On success, destroy old qdisc.
687 */
688
689 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
690 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
691 struct Qdisc *new, struct Qdisc *old)
692 {
693 struct Qdisc *q = old;
694 struct net *net = dev_net(dev);
695 int err = 0;
696
697 if (parent == NULL) {
698 unsigned int i, num_q, ingress;
699
700 ingress = 0;
701 num_q = dev->num_tx_queues;
702 if ((q && q->flags & TCQ_F_INGRESS) ||
703 (new && new->flags & TCQ_F_INGRESS)) {
704 num_q = 1;
705 ingress = 1;
706 if (!dev_ingress_queue(dev))
707 return -ENOENT;
708 }
709
710 if (dev->flags & IFF_UP)
711 dev_deactivate(dev);
712
713 if (new && new->ops->attach) {
714 new->ops->attach(new);
715 num_q = 0;
716 }
717
718 for (i = 0; i < num_q; i++) {
719 struct netdev_queue *dev_queue = dev_ingress_queue(dev);
720
721 if (!ingress)
722 dev_queue = netdev_get_tx_queue(dev, i);
723
724 old = dev_graft_qdisc(dev_queue, new);
725 if (new && i > 0)
726 atomic_inc(&new->refcnt);
727
728 if (!ingress)
729 qdisc_destroy(old);
730 }
731
732 if (!ingress) {
733 notify_and_destroy(net, skb, n, classid,
734 dev->qdisc, new);
735 if (new && !new->ops->attach)
736 atomic_inc(&new->refcnt);
737 dev->qdisc = new ? : &noop_qdisc;
738 } else {
739 notify_and_destroy(net, skb, n, classid, old, new);
740 }
741
742 if (dev->flags & IFF_UP)
743 dev_activate(dev);
744 } else {
745 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
746
747 err = -EOPNOTSUPP;
748 if (cops && cops->graft) {
749 unsigned long cl = cops->get(parent, classid);
750 if (cl) {
751 err = cops->graft(parent, cl, new, &old);
752 cops->put(parent, cl);
753 } else
754 err = -ENOENT;
755 }
756 if (!err)
757 notify_and_destroy(net, skb, n, classid, old, new);
758 }
759 return err;
760 }
761
762 /* lockdep annotation is needed for ingress; egress gets it only for name */
763 static struct lock_class_key qdisc_tx_lock;
764 static struct lock_class_key qdisc_rx_lock;
765
766 /*
767 Allocate and initialize new qdisc.
768
769 Parameters are passed via opt.
770 */
771
772 static struct Qdisc *
773 qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
774 struct Qdisc *p, u32 parent, u32 handle,
775 struct nlattr **tca, int *errp)
776 {
777 int err;
778 struct nlattr *kind = tca[TCA_KIND];
779 struct Qdisc *sch;
780 struct Qdisc_ops *ops;
781 struct qdisc_size_table *stab;
782
783 ops = qdisc_lookup_ops(kind);
784 #ifdef CONFIG_MODULES
785 if (ops == NULL && kind != NULL) {
786 char name[IFNAMSIZ];
787 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
788 /* We dropped the RTNL semaphore in order to
789 * perform the module load. So, even if we
790 * succeeded in loading the module we have to
791 * tell the caller to replay the request. We
792 * indicate this using -EAGAIN.
793 * We replay the request because the device may
794 * go away in the mean time.
795 */
796 rtnl_unlock();
797 request_module("sch_%s", name);
798 rtnl_lock();
799 ops = qdisc_lookup_ops(kind);
800 if (ops != NULL) {
801 /* We will try again qdisc_lookup_ops,
802 * so don't keep a reference.
803 */
804 module_put(ops->owner);
805 err = -EAGAIN;
806 goto err_out;
807 }
808 }
809 }
810 #endif
811
812 err = -ENOENT;
813 if (ops == NULL)
814 goto err_out;
815
816 sch = qdisc_alloc(dev_queue, ops);
817 if (IS_ERR(sch)) {
818 err = PTR_ERR(sch);
819 goto err_out2;
820 }
821
822 sch->parent = parent;
823
824 if (handle == TC_H_INGRESS) {
825 sch->flags |= TCQ_F_INGRESS;
826 handle = TC_H_MAKE(TC_H_INGRESS, 0);
827 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
828 } else {
829 if (handle == 0) {
830 handle = qdisc_alloc_handle(dev);
831 err = -ENOMEM;
832 if (handle == 0)
833 goto err_out3;
834 }
835 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
836 if (!netif_is_multiqueue(dev))
837 sch->flags |= TCQ_F_ONETXQUEUE;
838 }
839
840 sch->handle = handle;
841
842 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
843 if (tca[TCA_STAB]) {
844 stab = qdisc_get_stab(tca[TCA_STAB]);
845 if (IS_ERR(stab)) {
846 err = PTR_ERR(stab);
847 goto err_out4;
848 }
849 rcu_assign_pointer(sch->stab, stab);
850 }
851 if (tca[TCA_RATE]) {
852 spinlock_t *root_lock;
853
854 err = -EOPNOTSUPP;
855 if (sch->flags & TCQ_F_MQROOT)
856 goto err_out4;
857
858 if ((sch->parent != TC_H_ROOT) &&
859 !(sch->flags & TCQ_F_INGRESS) &&
860 (!p || !(p->flags & TCQ_F_MQROOT)))
861 root_lock = qdisc_root_sleeping_lock(sch);
862 else
863 root_lock = qdisc_lock(sch);
864
865 err = gen_new_estimator(&sch->bstats, &sch->rate_est,
866 root_lock, tca[TCA_RATE]);
867 if (err)
868 goto err_out4;
869 }
870
871 qdisc_list_add(sch);
872
873 return sch;
874 }
875 err_out3:
876 dev_put(dev);
877 kfree((char *) sch - sch->padded);
878 err_out2:
879 module_put(ops->owner);
880 err_out:
881 *errp = err;
882 return NULL;
883
884 err_out4:
885 /*
886 * Any broken qdiscs that would require a ops->reset() here?
887 * The qdisc was never in action so it shouldn't be necessary.
888 */
889 qdisc_put_stab(rtnl_dereference(sch->stab));
890 if (ops->destroy)
891 ops->destroy(sch);
892 goto err_out3;
893 }
894
895 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
896 {
897 struct qdisc_size_table *ostab, *stab = NULL;
898 int err = 0;
899
900 if (tca[TCA_OPTIONS]) {
901 if (sch->ops->change == NULL)
902 return -EINVAL;
903 err = sch->ops->change(sch, tca[TCA_OPTIONS]);
904 if (err)
905 return err;
906 }
907
908 if (tca[TCA_STAB]) {
909 stab = qdisc_get_stab(tca[TCA_STAB]);
910 if (IS_ERR(stab))
911 return PTR_ERR(stab);
912 }
913
914 ostab = rtnl_dereference(sch->stab);
915 rcu_assign_pointer(sch->stab, stab);
916 qdisc_put_stab(ostab);
917
918 if (tca[TCA_RATE]) {
919 /* NB: ignores errors from replace_estimator
920 because change can't be undone. */
921 if (sch->flags & TCQ_F_MQROOT)
922 goto out;
923 gen_replace_estimator(&sch->bstats, &sch->rate_est,
924 qdisc_root_sleeping_lock(sch),
925 tca[TCA_RATE]);
926 }
927 out:
928 return 0;
929 }
930
931 struct check_loop_arg {
932 struct qdisc_walker w;
933 struct Qdisc *p;
934 int depth;
935 };
936
937 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
938
939 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
940 {
941 struct check_loop_arg arg;
942
943 if (q->ops->cl_ops == NULL)
944 return 0;
945
946 arg.w.stop = arg.w.skip = arg.w.count = 0;
947 arg.w.fn = check_loop_fn;
948 arg.depth = depth;
949 arg.p = p;
950 q->ops->cl_ops->walk(q, &arg.w);
951 return arg.w.stop ? -ELOOP : 0;
952 }
953
954 static int
955 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
956 {
957 struct Qdisc *leaf;
958 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
959 struct check_loop_arg *arg = (struct check_loop_arg *)w;
960
961 leaf = cops->leaf(q, cl);
962 if (leaf) {
963 if (leaf == arg->p || arg->depth > 7)
964 return -ELOOP;
965 return check_loop(leaf, arg->p, arg->depth + 1);
966 }
967 return 0;
968 }
969
970 /*
971 * Delete/get qdisc.
972 */
973
974 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
975 {
976 struct net *net = sock_net(skb->sk);
977 struct tcmsg *tcm = nlmsg_data(n);
978 struct nlattr *tca[TCA_MAX + 1];
979 struct net_device *dev;
980 u32 clid = tcm->tcm_parent;
981 struct Qdisc *q = NULL;
982 struct Qdisc *p = NULL;
983 int err;
984
985 if ((n->nlmsg_type != RTM_GETQDISC) && !capable(CAP_NET_ADMIN))
986 return -EPERM;
987
988 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
989 if (!dev)
990 return -ENODEV;
991
992 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
993 if (err < 0)
994 return err;
995
996 if (clid) {
997 if (clid != TC_H_ROOT) {
998 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
999 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1000 if (!p)
1001 return -ENOENT;
1002 q = qdisc_leaf(p, clid);
1003 } else if (dev_ingress_queue(dev)) {
1004 q = dev_ingress_queue(dev)->qdisc_sleeping;
1005 }
1006 } else {
1007 q = dev->qdisc;
1008 }
1009 if (!q)
1010 return -ENOENT;
1011
1012 if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
1013 return -EINVAL;
1014 } else {
1015 q = qdisc_lookup(dev, tcm->tcm_handle);
1016 if (!q)
1017 return -ENOENT;
1018 }
1019
1020 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1021 return -EINVAL;
1022
1023 if (n->nlmsg_type == RTM_DELQDISC) {
1024 if (!clid)
1025 return -EINVAL;
1026 if (q->handle == 0)
1027 return -ENOENT;
1028 err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
1029 if (err != 0)
1030 return err;
1031 } else {
1032 qdisc_notify(net, skb, n, clid, NULL, q);
1033 }
1034 return 0;
1035 }
1036
1037 /*
1038 * Create/change qdisc.
1039 */
1040
1041 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1042 {
1043 struct net *net = sock_net(skb->sk);
1044 struct tcmsg *tcm;
1045 struct nlattr *tca[TCA_MAX + 1];
1046 struct net_device *dev;
1047 u32 clid;
1048 struct Qdisc *q, *p;
1049 int err;
1050
1051 if (!capable(CAP_NET_ADMIN))
1052 return -EPERM;
1053
1054 replay:
1055 /* Reinit, just in case something touches this. */
1056 tcm = nlmsg_data(n);
1057 clid = tcm->tcm_parent;
1058 q = p = NULL;
1059
1060 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1061 if (!dev)
1062 return -ENODEV;
1063
1064 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1065 if (err < 0)
1066 return err;
1067
1068 if (clid) {
1069 if (clid != TC_H_ROOT) {
1070 if (clid != TC_H_INGRESS) {
1071 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1072 if (!p)
1073 return -ENOENT;
1074 q = qdisc_leaf(p, clid);
1075 } else if (dev_ingress_queue_create(dev)) {
1076 q = dev_ingress_queue(dev)->qdisc_sleeping;
1077 }
1078 } else {
1079 q = dev->qdisc;
1080 }
1081
1082 /* It may be default qdisc, ignore it */
1083 if (q && q->handle == 0)
1084 q = NULL;
1085
1086 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1087 if (tcm->tcm_handle) {
1088 if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
1089 return -EEXIST;
1090 if (TC_H_MIN(tcm->tcm_handle))
1091 return -EINVAL;
1092 q = qdisc_lookup(dev, tcm->tcm_handle);
1093 if (!q)
1094 goto create_n_graft;
1095 if (n->nlmsg_flags & NLM_F_EXCL)
1096 return -EEXIST;
1097 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1098 return -EINVAL;
1099 if (q == p ||
1100 (p && check_loop(q, p, 0)))
1101 return -ELOOP;
1102 atomic_inc(&q->refcnt);
1103 goto graft;
1104 } else {
1105 if (!q)
1106 goto create_n_graft;
1107
1108 /* This magic test requires explanation.
1109 *
1110 * We know, that some child q is already
1111 * attached to this parent and have choice:
1112 * either to change it or to create/graft new one.
1113 *
1114 * 1. We are allowed to create/graft only
1115 * if CREATE and REPLACE flags are set.
1116 *
1117 * 2. If EXCL is set, requestor wanted to say,
1118 * that qdisc tcm_handle is not expected
1119 * to exist, so that we choose create/graft too.
1120 *
1121 * 3. The last case is when no flags are set.
1122 * Alas, it is sort of hole in API, we
1123 * cannot decide what to do unambiguously.
1124 * For now we select create/graft, if
1125 * user gave KIND, which does not match existing.
1126 */
1127 if ((n->nlmsg_flags & NLM_F_CREATE) &&
1128 (n->nlmsg_flags & NLM_F_REPLACE) &&
1129 ((n->nlmsg_flags & NLM_F_EXCL) ||
1130 (tca[TCA_KIND] &&
1131 nla_strcmp(tca[TCA_KIND], q->ops->id))))
1132 goto create_n_graft;
1133 }
1134 }
1135 } else {
1136 if (!tcm->tcm_handle)
1137 return -EINVAL;
1138 q = qdisc_lookup(dev, tcm->tcm_handle);
1139 }
1140
1141 /* Change qdisc parameters */
1142 if (q == NULL)
1143 return -ENOENT;
1144 if (n->nlmsg_flags & NLM_F_EXCL)
1145 return -EEXIST;
1146 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1147 return -EINVAL;
1148 err = qdisc_change(q, tca);
1149 if (err == 0)
1150 qdisc_notify(net, skb, n, clid, NULL, q);
1151 return err;
1152
1153 create_n_graft:
1154 if (!(n->nlmsg_flags & NLM_F_CREATE))
1155 return -ENOENT;
1156 if (clid == TC_H_INGRESS) {
1157 if (dev_ingress_queue(dev))
1158 q = qdisc_create(dev, dev_ingress_queue(dev), p,
1159 tcm->tcm_parent, tcm->tcm_parent,
1160 tca, &err);
1161 else
1162 err = -ENOENT;
1163 } else {
1164 struct netdev_queue *dev_queue;
1165
1166 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1167 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1168 else if (p)
1169 dev_queue = p->dev_queue;
1170 else
1171 dev_queue = netdev_get_tx_queue(dev, 0);
1172
1173 q = qdisc_create(dev, dev_queue, p,
1174 tcm->tcm_parent, tcm->tcm_handle,
1175 tca, &err);
1176 }
1177 if (q == NULL) {
1178 if (err == -EAGAIN)
1179 goto replay;
1180 return err;
1181 }
1182
1183 graft:
1184 err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
1185 if (err) {
1186 if (q)
1187 qdisc_destroy(q);
1188 return err;
1189 }
1190
1191 return 0;
1192 }
1193
1194 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1195 u32 portid, u32 seq, u16 flags, int event)
1196 {
1197 struct tcmsg *tcm;
1198 struct nlmsghdr *nlh;
1199 unsigned char *b = skb_tail_pointer(skb);
1200 struct gnet_dump d;
1201 struct qdisc_size_table *stab;
1202
1203 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1204 if (!nlh)
1205 goto out_nlmsg_trim;
1206 tcm = nlmsg_data(nlh);
1207 tcm->tcm_family = AF_UNSPEC;
1208 tcm->tcm__pad1 = 0;
1209 tcm->tcm__pad2 = 0;
1210 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1211 tcm->tcm_parent = clid;
1212 tcm->tcm_handle = q->handle;
1213 tcm->tcm_info = atomic_read(&q->refcnt);
1214 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1215 goto nla_put_failure;
1216 if (q->ops->dump && q->ops->dump(q, skb) < 0)
1217 goto nla_put_failure;
1218 q->qstats.qlen = q->q.qlen;
1219
1220 stab = rtnl_dereference(q->stab);
1221 if (stab && qdisc_dump_stab(skb, stab) < 0)
1222 goto nla_put_failure;
1223
1224 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1225 qdisc_root_sleeping_lock(q), &d) < 0)
1226 goto nla_put_failure;
1227
1228 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1229 goto nla_put_failure;
1230
1231 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
1232 gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
1233 gnet_stats_copy_queue(&d, &q->qstats) < 0)
1234 goto nla_put_failure;
1235
1236 if (gnet_stats_finish_copy(&d) < 0)
1237 goto nla_put_failure;
1238
1239 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1240 return skb->len;
1241
1242 out_nlmsg_trim:
1243 nla_put_failure:
1244 nlmsg_trim(skb, b);
1245 return -1;
1246 }
1247
1248 static bool tc_qdisc_dump_ignore(struct Qdisc *q)
1249 {
1250 return (q->flags & TCQ_F_BUILTIN) ? true : false;
1251 }
1252
1253 static int qdisc_notify(struct net *net, struct sk_buff *oskb,
1254 struct nlmsghdr *n, u32 clid,
1255 struct Qdisc *old, struct Qdisc *new)
1256 {
1257 struct sk_buff *skb;
1258 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1259
1260 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1261 if (!skb)
1262 return -ENOBUFS;
1263
1264 if (old && !tc_qdisc_dump_ignore(old)) {
1265 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
1266 0, RTM_DELQDISC) < 0)
1267 goto err_out;
1268 }
1269 if (new && !tc_qdisc_dump_ignore(new)) {
1270 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
1271 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
1272 goto err_out;
1273 }
1274
1275 if (skb->len)
1276 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1277 n->nlmsg_flags & NLM_F_ECHO);
1278
1279 err_out:
1280 kfree_skb(skb);
1281 return -EINVAL;
1282 }
1283
1284 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1285 struct netlink_callback *cb,
1286 int *q_idx_p, int s_q_idx)
1287 {
1288 int ret = 0, q_idx = *q_idx_p;
1289 struct Qdisc *q;
1290
1291 if (!root)
1292 return 0;
1293
1294 q = root;
1295 if (q_idx < s_q_idx) {
1296 q_idx++;
1297 } else {
1298 if (!tc_qdisc_dump_ignore(q) &&
1299 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1300 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1301 goto done;
1302 q_idx++;
1303 }
1304 list_for_each_entry(q, &root->list, list) {
1305 if (q_idx < s_q_idx) {
1306 q_idx++;
1307 continue;
1308 }
1309 if (!tc_qdisc_dump_ignore(q) &&
1310 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1311 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1312 goto done;
1313 q_idx++;
1314 }
1315
1316 out:
1317 *q_idx_p = q_idx;
1318 return ret;
1319 done:
1320 ret = -1;
1321 goto out;
1322 }
1323
1324 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1325 {
1326 struct net *net = sock_net(skb->sk);
1327 int idx, q_idx;
1328 int s_idx, s_q_idx;
1329 struct net_device *dev;
1330
1331 s_idx = cb->args[0];
1332 s_q_idx = q_idx = cb->args[1];
1333
1334 rcu_read_lock();
1335 idx = 0;
1336 for_each_netdev_rcu(net, dev) {
1337 struct netdev_queue *dev_queue;
1338
1339 if (idx < s_idx)
1340 goto cont;
1341 if (idx > s_idx)
1342 s_q_idx = 0;
1343 q_idx = 0;
1344
1345 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1346 goto done;
1347
1348 dev_queue = dev_ingress_queue(dev);
1349 if (dev_queue &&
1350 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1351 &q_idx, s_q_idx) < 0)
1352 goto done;
1353
1354 cont:
1355 idx++;
1356 }
1357
1358 done:
1359 rcu_read_unlock();
1360
1361 cb->args[0] = idx;
1362 cb->args[1] = q_idx;
1363
1364 return skb->len;
1365 }
1366
1367
1368
1369 /************************************************
1370 * Traffic classes manipulation. *
1371 ************************************************/
1372
1373
1374
1375 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1376 {
1377 struct net *net = sock_net(skb->sk);
1378 struct tcmsg *tcm = nlmsg_data(n);
1379 struct nlattr *tca[TCA_MAX + 1];
1380 struct net_device *dev;
1381 struct Qdisc *q = NULL;
1382 const struct Qdisc_class_ops *cops;
1383 unsigned long cl = 0;
1384 unsigned long new_cl;
1385 u32 portid = tcm->tcm_parent;
1386 u32 clid = tcm->tcm_handle;
1387 u32 qid = TC_H_MAJ(clid);
1388 int err;
1389
1390 if ((n->nlmsg_type != RTM_GETTCLASS) && !capable(CAP_NET_ADMIN))
1391 return -EPERM;
1392
1393 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1394 if (!dev)
1395 return -ENODEV;
1396
1397 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1398 if (err < 0)
1399 return err;
1400
1401 /*
1402 parent == TC_H_UNSPEC - unspecified parent.
1403 parent == TC_H_ROOT - class is root, which has no parent.
1404 parent == X:0 - parent is root class.
1405 parent == X:Y - parent is a node in hierarchy.
1406 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
1407
1408 handle == 0:0 - generate handle from kernel pool.
1409 handle == 0:Y - class is X:Y, where X:0 is qdisc.
1410 handle == X:Y - clear.
1411 handle == X:0 - root class.
1412 */
1413
1414 /* Step 1. Determine qdisc handle X:0 */
1415
1416 if (portid != TC_H_ROOT) {
1417 u32 qid1 = TC_H_MAJ(portid);
1418
1419 if (qid && qid1) {
1420 /* If both majors are known, they must be identical. */
1421 if (qid != qid1)
1422 return -EINVAL;
1423 } else if (qid1) {
1424 qid = qid1;
1425 } else if (qid == 0)
1426 qid = dev->qdisc->handle;
1427
1428 /* Now qid is genuine qdisc handle consistent
1429 * both with parent and child.
1430 *
1431 * TC_H_MAJ(portid) still may be unspecified, complete it now.
1432 */
1433 if (portid)
1434 portid = TC_H_MAKE(qid, portid);
1435 } else {
1436 if (qid == 0)
1437 qid = dev->qdisc->handle;
1438 }
1439
1440 /* OK. Locate qdisc */
1441 q = qdisc_lookup(dev, qid);
1442 if (!q)
1443 return -ENOENT;
1444
1445 /* An check that it supports classes */
1446 cops = q->ops->cl_ops;
1447 if (cops == NULL)
1448 return -EINVAL;
1449
1450 /* Now try to get class */
1451 if (clid == 0) {
1452 if (portid == TC_H_ROOT)
1453 clid = qid;
1454 } else
1455 clid = TC_H_MAKE(qid, clid);
1456
1457 if (clid)
1458 cl = cops->get(q, clid);
1459
1460 if (cl == 0) {
1461 err = -ENOENT;
1462 if (n->nlmsg_type != RTM_NEWTCLASS ||
1463 !(n->nlmsg_flags & NLM_F_CREATE))
1464 goto out;
1465 } else {
1466 switch (n->nlmsg_type) {
1467 case RTM_NEWTCLASS:
1468 err = -EEXIST;
1469 if (n->nlmsg_flags & NLM_F_EXCL)
1470 goto out;
1471 break;
1472 case RTM_DELTCLASS:
1473 err = -EOPNOTSUPP;
1474 if (cops->delete)
1475 err = cops->delete(q, cl);
1476 if (err == 0)
1477 tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS);
1478 goto out;
1479 case RTM_GETTCLASS:
1480 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
1481 goto out;
1482 default:
1483 err = -EINVAL;
1484 goto out;
1485 }
1486 }
1487
1488 new_cl = cl;
1489 err = -EOPNOTSUPP;
1490 if (cops->change)
1491 err = cops->change(q, clid, portid, tca, &new_cl);
1492 if (err == 0)
1493 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
1494
1495 out:
1496 if (cl)
1497 cops->put(q, cl);
1498
1499 return err;
1500 }
1501
1502
1503 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1504 unsigned long cl,
1505 u32 portid, u32 seq, u16 flags, int event)
1506 {
1507 struct tcmsg *tcm;
1508 struct nlmsghdr *nlh;
1509 unsigned char *b = skb_tail_pointer(skb);
1510 struct gnet_dump d;
1511 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1512
1513 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1514 if (!nlh)
1515 goto out_nlmsg_trim;
1516 tcm = nlmsg_data(nlh);
1517 tcm->tcm_family = AF_UNSPEC;
1518 tcm->tcm__pad1 = 0;
1519 tcm->tcm__pad2 = 0;
1520 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1521 tcm->tcm_parent = q->handle;
1522 tcm->tcm_handle = q->handle;
1523 tcm->tcm_info = 0;
1524 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1525 goto nla_put_failure;
1526 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1527 goto nla_put_failure;
1528
1529 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1530 qdisc_root_sleeping_lock(q), &d) < 0)
1531 goto nla_put_failure;
1532
1533 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1534 goto nla_put_failure;
1535
1536 if (gnet_stats_finish_copy(&d) < 0)
1537 goto nla_put_failure;
1538
1539 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1540 return skb->len;
1541
1542 out_nlmsg_trim:
1543 nla_put_failure:
1544 nlmsg_trim(skb, b);
1545 return -1;
1546 }
1547
1548 static int tclass_notify(struct net *net, struct sk_buff *oskb,
1549 struct nlmsghdr *n, struct Qdisc *q,
1550 unsigned long cl, int event)
1551 {
1552 struct sk_buff *skb;
1553 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1554
1555 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1556 if (!skb)
1557 return -ENOBUFS;
1558
1559 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
1560 kfree_skb(skb);
1561 return -EINVAL;
1562 }
1563
1564 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1565 n->nlmsg_flags & NLM_F_ECHO);
1566 }
1567
1568 struct qdisc_dump_args {
1569 struct qdisc_walker w;
1570 struct sk_buff *skb;
1571 struct netlink_callback *cb;
1572 };
1573
1574 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
1575 {
1576 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
1577
1578 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
1579 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
1580 }
1581
1582 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
1583 struct tcmsg *tcm, struct netlink_callback *cb,
1584 int *t_p, int s_t)
1585 {
1586 struct qdisc_dump_args arg;
1587
1588 if (tc_qdisc_dump_ignore(q) ||
1589 *t_p < s_t || !q->ops->cl_ops ||
1590 (tcm->tcm_parent &&
1591 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
1592 (*t_p)++;
1593 return 0;
1594 }
1595 if (*t_p > s_t)
1596 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
1597 arg.w.fn = qdisc_class_dump;
1598 arg.skb = skb;
1599 arg.cb = cb;
1600 arg.w.stop = 0;
1601 arg.w.skip = cb->args[1];
1602 arg.w.count = 0;
1603 q->ops->cl_ops->walk(q, &arg.w);
1604 cb->args[1] = arg.w.count;
1605 if (arg.w.stop)
1606 return -1;
1607 (*t_p)++;
1608 return 0;
1609 }
1610
1611 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
1612 struct tcmsg *tcm, struct netlink_callback *cb,
1613 int *t_p, int s_t)
1614 {
1615 struct Qdisc *q;
1616
1617 if (!root)
1618 return 0;
1619
1620 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
1621 return -1;
1622
1623 list_for_each_entry(q, &root->list, list) {
1624 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
1625 return -1;
1626 }
1627
1628 return 0;
1629 }
1630
1631 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
1632 {
1633 struct tcmsg *tcm = nlmsg_data(cb->nlh);
1634 struct net *net = sock_net(skb->sk);
1635 struct netdev_queue *dev_queue;
1636 struct net_device *dev;
1637 int t, s_t;
1638
1639 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
1640 return 0;
1641 dev = dev_get_by_index(net, tcm->tcm_ifindex);
1642 if (!dev)
1643 return 0;
1644
1645 s_t = cb->args[0];
1646 t = 0;
1647
1648 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1649 goto done;
1650
1651 dev_queue = dev_ingress_queue(dev);
1652 if (dev_queue &&
1653 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
1654 &t, s_t) < 0)
1655 goto done;
1656
1657 done:
1658 cb->args[0] = t;
1659
1660 dev_put(dev);
1661 return skb->len;
1662 }
1663
1664 /* Main classifier routine: scans classifier chain attached
1665 * to this qdisc, (optionally) tests for protocol and asks
1666 * specific classifiers.
1667 */
1668 int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
1669 struct tcf_result *res)
1670 {
1671 __be16 protocol = skb->protocol;
1672 int err;
1673
1674 for (; tp; tp = tp->next) {
1675 if (tp->protocol != protocol &&
1676 tp->protocol != htons(ETH_P_ALL))
1677 continue;
1678 err = tp->classify(skb, tp, res);
1679
1680 if (err >= 0) {
1681 #ifdef CONFIG_NET_CLS_ACT
1682 if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
1683 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
1684 #endif
1685 return err;
1686 }
1687 }
1688 return -1;
1689 }
1690 EXPORT_SYMBOL(tc_classify_compat);
1691
1692 int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1693 struct tcf_result *res)
1694 {
1695 int err = 0;
1696 #ifdef CONFIG_NET_CLS_ACT
1697 const struct tcf_proto *otp = tp;
1698 reclassify:
1699 #endif
1700
1701 err = tc_classify_compat(skb, tp, res);
1702 #ifdef CONFIG_NET_CLS_ACT
1703 if (err == TC_ACT_RECLASSIFY) {
1704 u32 verd = G_TC_VERD(skb->tc_verd);
1705 tp = otp;
1706
1707 if (verd++ >= MAX_REC_LOOP) {
1708 net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n",
1709 tp->q->ops->id,
1710 tp->prio & 0xffff,
1711 ntohs(tp->protocol));
1712 return TC_ACT_SHOT;
1713 }
1714 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
1715 goto reclassify;
1716 }
1717 #endif
1718 return err;
1719 }
1720 EXPORT_SYMBOL(tc_classify);
1721
1722 void tcf_destroy(struct tcf_proto *tp)
1723 {
1724 tp->ops->destroy(tp);
1725 module_put(tp->ops->owner);
1726 kfree(tp);
1727 }
1728
1729 void tcf_destroy_chain(struct tcf_proto **fl)
1730 {
1731 struct tcf_proto *tp;
1732
1733 while ((tp = *fl) != NULL) {
1734 *fl = tp->next;
1735 tcf_destroy(tp);
1736 }
1737 }
1738 EXPORT_SYMBOL(tcf_destroy_chain);
1739
1740 #ifdef CONFIG_PROC_FS
1741 static int psched_show(struct seq_file *seq, void *v)
1742 {
1743 struct timespec ts;
1744
1745 hrtimer_get_res(CLOCK_MONOTONIC, &ts);
1746 seq_printf(seq, "%08x %08x %08x %08x\n",
1747 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1748 1000000,
1749 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
1750
1751 return 0;
1752 }
1753
1754 static int psched_open(struct inode *inode, struct file *file)
1755 {
1756 return single_open(file, psched_show, NULL);
1757 }
1758
1759 static const struct file_operations psched_fops = {
1760 .owner = THIS_MODULE,
1761 .open = psched_open,
1762 .read = seq_read,
1763 .llseek = seq_lseek,
1764 .release = single_release,
1765 };
1766
1767 static int __net_init psched_net_init(struct net *net)
1768 {
1769 struct proc_dir_entry *e;
1770
1771 e = proc_net_fops_create(net, "psched", 0, &psched_fops);
1772 if (e == NULL)
1773 return -ENOMEM;
1774
1775 return 0;
1776 }
1777
1778 static void __net_exit psched_net_exit(struct net *net)
1779 {
1780 proc_net_remove(net, "psched");
1781 }
1782 #else
1783 static int __net_init psched_net_init(struct net *net)
1784 {
1785 return 0;
1786 }
1787
1788 static void __net_exit psched_net_exit(struct net *net)
1789 {
1790 }
1791 #endif
1792
1793 static struct pernet_operations psched_net_ops = {
1794 .init = psched_net_init,
1795 .exit = psched_net_exit,
1796 };
1797
1798 static int __init pktsched_init(void)
1799 {
1800 int err;
1801
1802 err = register_pernet_subsys(&psched_net_ops);
1803 if (err) {
1804 pr_err("pktsched_init: "
1805 "cannot initialize per netns operations\n");
1806 return err;
1807 }
1808
1809 register_qdisc(&pfifo_qdisc_ops);
1810 register_qdisc(&bfifo_qdisc_ops);
1811 register_qdisc(&pfifo_head_drop_qdisc_ops);
1812 register_qdisc(&mq_qdisc_ops);
1813
1814 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
1815 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
1816 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, NULL);
1817 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
1818 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1819 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, NULL);
1820
1821 return 0;
1822 }
1823
1824 subsys_initcall(pktsched_init);
Linus' kernel tree