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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
38static int qdisc_notify(struct net *net, struct sk_buff *oskb,
39 struct nlmsghdr *n, u32 clid,
40 struct Qdisc *old, struct Qdisc *new);
41static 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. */
126static DEFINE_RWLOCK(qdisc_mod_lock);
127
128
129/************************************************
130 * Queueing disciplines manipulation. *
131 ************************************************/
132
133
134/* The list of all installed queueing disciplines. */
135
136static struct Qdisc_ops *qdisc_base;
137
138/* Register/uregister queueing discipline */
139
140int 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;
174out:
175 write_unlock(&qdisc_mod_lock);
176 return rc;
177
178out_einval:
179 rc = -EINVAL;
180 goto out;
181}
182EXPORT_SYMBOL(register_qdisc);
183
184int 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}
201EXPORT_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
207static 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
222static 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
228void 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}
233EXPORT_SYMBOL(qdisc_list_del);
234
235struct 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);
247out:
248 return q;
249}
250
251static 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
270static 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
288static struct qdisc_rate_table *qdisc_rtab_list;
289
290struct 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}
315EXPORT_SYMBOL(qdisc_get_rtab);
316
317void 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}
334EXPORT_SYMBOL(qdisc_put_rtab);
335
336static LIST_HEAD(qdisc_stab_list);
337static DEFINE_SPINLOCK(qdisc_stab_lock);
338
339static 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
344static 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
401static void stab_kfree_rcu(struct rcu_head *head)
402{
403 kfree(container_of(head, struct qdisc_size_table, rcu));
404}
405
406void 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}
420EXPORT_SYMBOL(qdisc_put_stab);
421
422static 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
435nla_put_failure:
436 return -1;
437}
438
439void __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;
460out:
461 if (unlikely(pkt_len < 1))
462 pkt_len = 1;
463 qdisc_skb_cb(skb)->pkt_len = pkt_len;
464}
465EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
466
467void 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}
475EXPORT_SYMBOL(qdisc_warn_nonwc);
476
477static 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
488void 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}
494EXPORT_SYMBOL(qdisc_watchdog_init);
495
496void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires)
497{
498 ktime_t time;
499
500 if (test_bit(__QDISC_STATE_DEACTIVATED,
501 &qdisc_root_sleeping(wd->qdisc)->state))
502 return;
503
504 qdisc_throttled(wd->qdisc);
505 time = ktime_set(0, 0);
506 time = ktime_add_ns(time, PSCHED_TICKS2NS(expires));
507 hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS);
508}
509EXPORT_SYMBOL(qdisc_watchdog_schedule);
510
511void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
512{
513 hrtimer_cancel(&wd->timer);
514 qdisc_unthrottled(wd->qdisc);
515}
516EXPORT_SYMBOL(qdisc_watchdog_cancel);
517
518static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
519{
520 unsigned int size = n * sizeof(struct hlist_head), i;
521 struct hlist_head *h;
522
523 if (size <= PAGE_SIZE)
524 h = kmalloc(size, GFP_KERNEL);
525 else
526 h = (struct hlist_head *)
527 __get_free_pages(GFP_KERNEL, get_order(size));
528
529 if (h != NULL) {
530 for (i = 0; i < n; i++)
531 INIT_HLIST_HEAD(&h[i]);
532 }
533 return h;
534}
535
536static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
537{
538 unsigned int size = n * sizeof(struct hlist_head);
539
540 if (size <= PAGE_SIZE)
541 kfree(h);
542 else
543 free_pages((unsigned long)h, get_order(size));
544}
545
546void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
547{
548 struct Qdisc_class_common *cl;
549 struct hlist_node *n, *next;
550 struct hlist_head *nhash, *ohash;
551 unsigned int nsize, nmask, osize;
552 unsigned int i, h;
553
554 /* Rehash when load factor exceeds 0.75 */
555 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
556 return;
557 nsize = clhash->hashsize * 2;
558 nmask = nsize - 1;
559 nhash = qdisc_class_hash_alloc(nsize);
560 if (nhash == NULL)
561 return;
562
563 ohash = clhash->hash;
564 osize = clhash->hashsize;
565
566 sch_tree_lock(sch);
567 for (i = 0; i < osize; i++) {
568 hlist_for_each_entry_safe(cl, n, next, &ohash[i], hnode) {
569 h = qdisc_class_hash(cl->classid, nmask);
570 hlist_add_head(&cl->hnode, &nhash[h]);
571 }
572 }
573 clhash->hash = nhash;
574 clhash->hashsize = nsize;
575 clhash->hashmask = nmask;
576 sch_tree_unlock(sch);
577
578 qdisc_class_hash_free(ohash, osize);
579}
580EXPORT_SYMBOL(qdisc_class_hash_grow);
581
582int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
583{
584 unsigned int size = 4;
585
586 clhash->hash = qdisc_class_hash_alloc(size);
587 if (clhash->hash == NULL)
588 return -ENOMEM;
589 clhash->hashsize = size;
590 clhash->hashmask = size - 1;
591 clhash->hashelems = 0;
592 return 0;
593}
594EXPORT_SYMBOL(qdisc_class_hash_init);
595
596void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
597{
598 qdisc_class_hash_free(clhash->hash, clhash->hashsize);
599}
600EXPORT_SYMBOL(qdisc_class_hash_destroy);
601
602void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
603 struct Qdisc_class_common *cl)
604{
605 unsigned int h;
606
607 INIT_HLIST_NODE(&cl->hnode);
608 h = qdisc_class_hash(cl->classid, clhash->hashmask);
609 hlist_add_head(&cl->hnode, &clhash->hash[h]);
610 clhash->hashelems++;
611}
612EXPORT_SYMBOL(qdisc_class_hash_insert);
613
614void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
615 struct Qdisc_class_common *cl)
616{
617 hlist_del(&cl->hnode);
618 clhash->hashelems--;
619}
620EXPORT_SYMBOL(qdisc_class_hash_remove);
621
622/* Allocate an unique handle from space managed by kernel
623 * Possible range is [8000-FFFF]:0000 (0x8000 values)
624 */
625static u32 qdisc_alloc_handle(struct net_device *dev)
626{
627 int i = 0x8000;
628 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
629
630 do {
631 autohandle += TC_H_MAKE(0x10000U, 0);
632 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
633 autohandle = TC_H_MAKE(0x80000000U, 0);
634 if (!qdisc_lookup(dev, autohandle))
635 return autohandle;
636 cond_resched();
637 } while (--i > 0);
638
639 return 0;
640}
641
642void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
643{
644 const struct Qdisc_class_ops *cops;
645 unsigned long cl;
646 u32 parentid;
647
648 if (n == 0)
649 return;
650 while ((parentid = sch->parent)) {
651 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
652 return;
653
654 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
655 if (sch == NULL) {
656 WARN_ON(parentid != TC_H_ROOT);
657 return;
658 }
659 cops = sch->ops->cl_ops;
660 if (cops->qlen_notify) {
661 cl = cops->get(sch, parentid);
662 cops->qlen_notify(sch, cl);
663 cops->put(sch, cl);
664 }
665 sch->q.qlen -= n;
666 }
667}
668EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
669
670static void notify_and_destroy(struct net *net, struct sk_buff *skb,
671 struct nlmsghdr *n, u32 clid,
672 struct Qdisc *old, struct Qdisc *new)
673{
674 if (new || old)
675 qdisc_notify(net, skb, n, clid, old, new);
676
677 if (old)
678 qdisc_destroy(old);
679}
680
681/* Graft qdisc "new" to class "classid" of qdisc "parent" or
682 * to device "dev".
683 *
684 * When appropriate send a netlink notification using 'skb'
685 * and "n".
686 *
687 * On success, destroy old qdisc.
688 */
689
690static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
691 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
692 struct Qdisc *new, struct Qdisc *old)
693{
694 struct Qdisc *q = old;
695 struct net *net = dev_net(dev);
696 int err = 0;
697
698 if (parent == NULL) {
699 unsigned int i, num_q, ingress;
700
701 ingress = 0;
702 num_q = dev->num_tx_queues;
703 if ((q && q->flags & TCQ_F_INGRESS) ||
704 (new && new->flags & TCQ_F_INGRESS)) {
705 num_q = 1;
706 ingress = 1;
707 if (!dev_ingress_queue(dev))
708 return -ENOENT;
709 }
710
711 if (dev->flags & IFF_UP)
712 dev_deactivate(dev);
713
714 if (new && new->ops->attach) {
715 new->ops->attach(new);
716 num_q = 0;
717 }
718
719 for (i = 0; i < num_q; i++) {
720 struct netdev_queue *dev_queue = dev_ingress_queue(dev);
721
722 if (!ingress)
723 dev_queue = netdev_get_tx_queue(dev, i);
724
725 old = dev_graft_qdisc(dev_queue, new);
726 if (new && i > 0)
727 atomic_inc(&new->refcnt);
728
729 if (!ingress)
730 qdisc_destroy(old);
731 }
732
733 if (!ingress) {
734 notify_and_destroy(net, skb, n, classid,
735 dev->qdisc, new);
736 if (new && !new->ops->attach)
737 atomic_inc(&new->refcnt);
738 dev->qdisc = new ? : &noop_qdisc;
739 } else {
740 notify_and_destroy(net, skb, n, classid, old, new);
741 }
742
743 if (dev->flags & IFF_UP)
744 dev_activate(dev);
745 } else {
746 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
747
748 err = -EOPNOTSUPP;
749 if (cops && cops->graft) {
750 unsigned long cl = cops->get(parent, classid);
751 if (cl) {
752 err = cops->graft(parent, cl, new, &old);
753 cops->put(parent, cl);
754 } else
755 err = -ENOENT;
756 }
757 if (!err)
758 notify_and_destroy(net, skb, n, classid, old, new);
759 }
760 return err;
761}
762
763/* lockdep annotation is needed for ingress; egress gets it only for name */
764static struct lock_class_key qdisc_tx_lock;
765static struct lock_class_key qdisc_rx_lock;
766
767/*
768 Allocate and initialize new qdisc.
769
770 Parameters are passed via opt.
771 */
772
773static struct Qdisc *
774qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
775 struct Qdisc *p, u32 parent, u32 handle,
776 struct nlattr **tca, int *errp)
777{
778 int err;
779 struct nlattr *kind = tca[TCA_KIND];
780 struct Qdisc *sch;
781 struct Qdisc_ops *ops;
782 struct qdisc_size_table *stab;
783
784 ops = qdisc_lookup_ops(kind);
785#ifdef CONFIG_MODULES
786 if (ops == NULL && kind != NULL) {
787 char name[IFNAMSIZ];
788 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
789 /* We dropped the RTNL semaphore in order to
790 * perform the module load. So, even if we
791 * succeeded in loading the module we have to
792 * tell the caller to replay the request. We
793 * indicate this using -EAGAIN.
794 * We replay the request because the device may
795 * go away in the mean time.
796 */
797 rtnl_unlock();
798 request_module("sch_%s", name);
799 rtnl_lock();
800 ops = qdisc_lookup_ops(kind);
801 if (ops != NULL) {
802 /* We will try again qdisc_lookup_ops,
803 * so don't keep a reference.
804 */
805 module_put(ops->owner);
806 err = -EAGAIN;
807 goto err_out;
808 }
809 }
810 }
811#endif
812
813 err = -ENOENT;
814 if (ops == NULL)
815 goto err_out;
816
817 sch = qdisc_alloc(dev_queue, ops);
818 if (IS_ERR(sch)) {
819 err = PTR_ERR(sch);
820 goto err_out2;
821 }
822
823 sch->parent = parent;
824
825 if (handle == TC_H_INGRESS) {
826 sch->flags |= TCQ_F_INGRESS;
827 handle = TC_H_MAKE(TC_H_INGRESS, 0);
828 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
829 } else {
830 if (handle == 0) {
831 handle = qdisc_alloc_handle(dev);
832 err = -ENOMEM;
833 if (handle == 0)
834 goto err_out3;
835 }
836 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
837 }
838
839 sch->handle = handle;
840
841 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
842 if (tca[TCA_STAB]) {
843 stab = qdisc_get_stab(tca[TCA_STAB]);
844 if (IS_ERR(stab)) {
845 err = PTR_ERR(stab);
846 goto err_out4;
847 }
848 rcu_assign_pointer(sch->stab, stab);
849 }
850 if (tca[TCA_RATE]) {
851 spinlock_t *root_lock;
852
853 err = -EOPNOTSUPP;
854 if (sch->flags & TCQ_F_MQROOT)
855 goto err_out4;
856
857 if ((sch->parent != TC_H_ROOT) &&
858 !(sch->flags & TCQ_F_INGRESS) &&
859 (!p || !(p->flags & TCQ_F_MQROOT)))
860 root_lock = qdisc_root_sleeping_lock(sch);
861 else
862 root_lock = qdisc_lock(sch);
863
864 err = gen_new_estimator(&sch->bstats, &sch->rate_est,
865 root_lock, tca[TCA_RATE]);
866 if (err)
867 goto err_out4;
868 }
869
870 qdisc_list_add(sch);
871
872 return sch;
873 }
874err_out3:
875 dev_put(dev);
876 kfree((char *) sch - sch->padded);
877err_out2:
878 module_put(ops->owner);
879err_out:
880 *errp = err;
881 return NULL;
882
883err_out4:
884 /*
885 * Any broken qdiscs that would require a ops->reset() here?
886 * The qdisc was never in action so it shouldn't be necessary.
887 */
888 qdisc_put_stab(rtnl_dereference(sch->stab));
889 if (ops->destroy)
890 ops->destroy(sch);
891 goto err_out3;
892}
893
894static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
895{
896 struct qdisc_size_table *ostab, *stab = NULL;
897 int err = 0;
898
899 if (tca[TCA_OPTIONS]) {
900 if (sch->ops->change == NULL)
901 return -EINVAL;
902 err = sch->ops->change(sch, tca[TCA_OPTIONS]);
903 if (err)
904 return err;
905 }
906
907 if (tca[TCA_STAB]) {
908 stab = qdisc_get_stab(tca[TCA_STAB]);
909 if (IS_ERR(stab))
910 return PTR_ERR(stab);
911 }
912
913 ostab = rtnl_dereference(sch->stab);
914 rcu_assign_pointer(sch->stab, stab);
915 qdisc_put_stab(ostab);
916
917 if (tca[TCA_RATE]) {
918 /* NB: ignores errors from replace_estimator
919 because change can't be undone. */
920 if (sch->flags & TCQ_F_MQROOT)
921 goto out;
922 gen_replace_estimator(&sch->bstats, &sch->rate_est,
923 qdisc_root_sleeping_lock(sch),
924 tca[TCA_RATE]);
925 }
926out:
927 return 0;
928}
929
930struct check_loop_arg {
931 struct qdisc_walker w;
932 struct Qdisc *p;
933 int depth;
934};
935
936static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
937
938static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
939{
940 struct check_loop_arg arg;
941
942 if (q->ops->cl_ops == NULL)
943 return 0;
944
945 arg.w.stop = arg.w.skip = arg.w.count = 0;
946 arg.w.fn = check_loop_fn;
947 arg.depth = depth;
948 arg.p = p;
949 q->ops->cl_ops->walk(q, &arg.w);
950 return arg.w.stop ? -ELOOP : 0;
951}
952
953static int
954check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
955{
956 struct Qdisc *leaf;
957 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
958 struct check_loop_arg *arg = (struct check_loop_arg *)w;
959
960 leaf = cops->leaf(q, cl);
961 if (leaf) {
962 if (leaf == arg->p || arg->depth > 7)
963 return -ELOOP;
964 return check_loop(leaf, arg->p, arg->depth + 1);
965 }
966 return 0;
967}
968
969/*
970 * Delete/get qdisc.
971 */
972
973static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
974{
975 struct net *net = sock_net(skb->sk);
976 struct tcmsg *tcm = NLMSG_DATA(n);
977 struct nlattr *tca[TCA_MAX + 1];
978 struct net_device *dev;
979 u32 clid = tcm->tcm_parent;
980 struct Qdisc *q = NULL;
981 struct Qdisc *p = NULL;
982 int err;
983
984 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
985 if (!dev)
986 return -ENODEV;
987
988 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
989 if (err < 0)
990 return err;
991
992 if (clid) {
993 if (clid != TC_H_ROOT) {
994 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
995 p = qdisc_lookup(dev, TC_H_MAJ(clid));
996 if (!p)
997 return -ENOENT;
998 q = qdisc_leaf(p, clid);
999 } else if (dev_ingress_queue(dev)) {
1000 q = dev_ingress_queue(dev)->qdisc_sleeping;
1001 }
1002 } else {
1003 q = dev->qdisc;
1004 }
1005 if (!q)
1006 return -ENOENT;
1007
1008 if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
1009 return -EINVAL;
1010 } else {
1011 q = qdisc_lookup(dev, tcm->tcm_handle);
1012 if (!q)
1013 return -ENOENT;
1014 }
1015
1016 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1017 return -EINVAL;
1018
1019 if (n->nlmsg_type == RTM_DELQDISC) {
1020 if (!clid)
1021 return -EINVAL;
1022 if (q->handle == 0)
1023 return -ENOENT;
1024 err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
1025 if (err != 0)
1026 return err;
1027 } else {
1028 qdisc_notify(net, skb, n, clid, NULL, q);
1029 }
1030 return 0;
1031}
1032
1033/*
1034 * Create/change qdisc.
1035 */
1036
1037static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1038{
1039 struct net *net = sock_net(skb->sk);
1040 struct tcmsg *tcm;
1041 struct nlattr *tca[TCA_MAX + 1];
1042 struct net_device *dev;
1043 u32 clid;
1044 struct Qdisc *q, *p;
1045 int err;
1046
1047replay:
1048 /* Reinit, just in case something touches this. */
1049 tcm = NLMSG_DATA(n);
1050 clid = tcm->tcm_parent;
1051 q = p = NULL;
1052
1053 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1054 if (!dev)
1055 return -ENODEV;
1056
1057 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1058 if (err < 0)
1059 return err;
1060
1061 if (clid) {
1062 if (clid != TC_H_ROOT) {
1063 if (clid != TC_H_INGRESS) {
1064 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1065 if (!p)
1066 return -ENOENT;
1067 q = qdisc_leaf(p, clid);
1068 } else if (dev_ingress_queue_create(dev)) {
1069 q = dev_ingress_queue(dev)->qdisc_sleeping;
1070 }
1071 } else {
1072 q = dev->qdisc;
1073 }
1074
1075 /* It may be default qdisc, ignore it */
1076 if (q && q->handle == 0)
1077 q = NULL;
1078
1079 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1080 if (tcm->tcm_handle) {
1081 if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
1082 return -EEXIST;
1083 if (TC_H_MIN(tcm->tcm_handle))
1084 return -EINVAL;
1085 q = qdisc_lookup(dev, tcm->tcm_handle);
1086 if (!q)
1087 goto create_n_graft;
1088 if (n->nlmsg_flags & NLM_F_EXCL)
1089 return -EEXIST;
1090 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1091 return -EINVAL;
1092 if (q == p ||
1093 (p && check_loop(q, p, 0)))
1094 return -ELOOP;
1095 atomic_inc(&q->refcnt);
1096 goto graft;
1097 } else {
1098 if (!q)
1099 goto create_n_graft;
1100
1101 /* This magic test requires explanation.
1102 *
1103 * We know, that some child q is already
1104 * attached to this parent and have choice:
1105 * either to change it or to create/graft new one.
1106 *
1107 * 1. We are allowed to create/graft only
1108 * if CREATE and REPLACE flags are set.
1109 *
1110 * 2. If EXCL is set, requestor wanted to say,
1111 * that qdisc tcm_handle is not expected
1112 * to exist, so that we choose create/graft too.
1113 *
1114 * 3. The last case is when no flags are set.
1115 * Alas, it is sort of hole in API, we
1116 * cannot decide what to do unambiguously.
1117 * For now we select create/graft, if
1118 * user gave KIND, which does not match existing.
1119 */
1120 if ((n->nlmsg_flags & NLM_F_CREATE) &&
1121 (n->nlmsg_flags & NLM_F_REPLACE) &&
1122 ((n->nlmsg_flags & NLM_F_EXCL) ||
1123 (tca[TCA_KIND] &&
1124 nla_strcmp(tca[TCA_KIND], q->ops->id))))
1125 goto create_n_graft;
1126 }
1127 }
1128 } else {
1129 if (!tcm->tcm_handle)
1130 return -EINVAL;
1131 q = qdisc_lookup(dev, tcm->tcm_handle);
1132 }
1133
1134 /* Change qdisc parameters */
1135 if (q == NULL)
1136 return -ENOENT;
1137 if (n->nlmsg_flags & NLM_F_EXCL)
1138 return -EEXIST;
1139 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1140 return -EINVAL;
1141 err = qdisc_change(q, tca);
1142 if (err == 0)
1143 qdisc_notify(net, skb, n, clid, NULL, q);
1144 return err;
1145
1146create_n_graft:
1147 if (!(n->nlmsg_flags & NLM_F_CREATE))
1148 return -ENOENT;
1149 if (clid == TC_H_INGRESS) {
1150 if (dev_ingress_queue(dev))
1151 q = qdisc_create(dev, dev_ingress_queue(dev), p,
1152 tcm->tcm_parent, tcm->tcm_parent,
1153 tca, &err);
1154 else
1155 err = -ENOENT;
1156 } else {
1157 struct netdev_queue *dev_queue;
1158
1159 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1160 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1161 else if (p)
1162 dev_queue = p->dev_queue;
1163 else
1164 dev_queue = netdev_get_tx_queue(dev, 0);
1165
1166 q = qdisc_create(dev, dev_queue, p,
1167 tcm->tcm_parent, tcm->tcm_handle,
1168 tca, &err);
1169 }
1170 if (q == NULL) {
1171 if (err == -EAGAIN)
1172 goto replay;
1173 return err;
1174 }
1175
1176graft:
1177 err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
1178 if (err) {
1179 if (q)
1180 qdisc_destroy(q);
1181 return err;
1182 }
1183
1184 return 0;
1185}
1186
1187static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1188 u32 pid, u32 seq, u16 flags, int event)
1189{
1190 struct tcmsg *tcm;
1191 struct nlmsghdr *nlh;
1192 unsigned char *b = skb_tail_pointer(skb);
1193 struct gnet_dump d;
1194 struct qdisc_size_table *stab;
1195
1196 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
1197 tcm = NLMSG_DATA(nlh);
1198 tcm->tcm_family = AF_UNSPEC;
1199 tcm->tcm__pad1 = 0;
1200 tcm->tcm__pad2 = 0;
1201 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1202 tcm->tcm_parent = clid;
1203 tcm->tcm_handle = q->handle;
1204 tcm->tcm_info = atomic_read(&q->refcnt);
1205 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1206 goto nla_put_failure;
1207 if (q->ops->dump && q->ops->dump(q, skb) < 0)
1208 goto nla_put_failure;
1209 q->qstats.qlen = q->q.qlen;
1210
1211 stab = rtnl_dereference(q->stab);
1212 if (stab && qdisc_dump_stab(skb, stab) < 0)
1213 goto nla_put_failure;
1214
1215 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1216 qdisc_root_sleeping_lock(q), &d) < 0)
1217 goto nla_put_failure;
1218
1219 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1220 goto nla_put_failure;
1221
1222 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
1223 gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
1224 gnet_stats_copy_queue(&d, &q->qstats) < 0)
1225 goto nla_put_failure;
1226
1227 if (gnet_stats_finish_copy(&d) < 0)
1228 goto nla_put_failure;
1229
1230 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1231 return skb->len;
1232
1233nlmsg_failure:
1234nla_put_failure:
1235 nlmsg_trim(skb, b);
1236 return -1;
1237}
1238
1239static bool tc_qdisc_dump_ignore(struct Qdisc *q)
1240{
1241 return (q->flags & TCQ_F_BUILTIN) ? true : false;
1242}
1243
1244static int qdisc_notify(struct net *net, struct sk_buff *oskb,
1245 struct nlmsghdr *n, u32 clid,
1246 struct Qdisc *old, struct Qdisc *new)
1247{
1248 struct sk_buff *skb;
1249 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1250
1251 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1252 if (!skb)
1253 return -ENOBUFS;
1254
1255 if (old && !tc_qdisc_dump_ignore(old)) {
1256 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq,
1257 0, RTM_DELQDISC) < 0)
1258 goto err_out;
1259 }
1260 if (new && !tc_qdisc_dump_ignore(new)) {
1261 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq,
1262 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
1263 goto err_out;
1264 }
1265
1266 if (skb->len)
1267 return rtnetlink_send(skb, net, pid, RTNLGRP_TC,
1268 n->nlmsg_flags & NLM_F_ECHO);
1269
1270err_out:
1271 kfree_skb(skb);
1272 return -EINVAL;
1273}
1274
1275static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1276 struct netlink_callback *cb,
1277 int *q_idx_p, int s_q_idx)
1278{
1279 int ret = 0, q_idx = *q_idx_p;
1280 struct Qdisc *q;
1281
1282 if (!root)
1283 return 0;
1284
1285 q = root;
1286 if (q_idx < s_q_idx) {
1287 q_idx++;
1288 } else {
1289 if (!tc_qdisc_dump_ignore(q) &&
1290 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid,
1291 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1292 goto done;
1293 q_idx++;
1294 }
1295 list_for_each_entry(q, &root->list, list) {
1296 if (q_idx < s_q_idx) {
1297 q_idx++;
1298 continue;
1299 }
1300 if (!tc_qdisc_dump_ignore(q) &&
1301 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid,
1302 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1303 goto done;
1304 q_idx++;
1305 }
1306
1307out:
1308 *q_idx_p = q_idx;
1309 return ret;
1310done:
1311 ret = -1;
1312 goto out;
1313}
1314
1315static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1316{
1317 struct net *net = sock_net(skb->sk);
1318 int idx, q_idx;
1319 int s_idx, s_q_idx;
1320 struct net_device *dev;
1321
1322 s_idx = cb->args[0];
1323 s_q_idx = q_idx = cb->args[1];
1324
1325 rcu_read_lock();
1326 idx = 0;
1327 for_each_netdev_rcu(net, dev) {
1328 struct netdev_queue *dev_queue;
1329
1330 if (idx < s_idx)
1331 goto cont;
1332 if (idx > s_idx)
1333 s_q_idx = 0;
1334 q_idx = 0;
1335
1336 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1337 goto done;
1338
1339 dev_queue = dev_ingress_queue(dev);
1340 if (dev_queue &&
1341 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1342 &q_idx, s_q_idx) < 0)
1343 goto done;
1344
1345cont:
1346 idx++;
1347 }
1348
1349done:
1350 rcu_read_unlock();
1351
1352 cb->args[0] = idx;
1353 cb->args[1] = q_idx;
1354
1355 return skb->len;
1356}
1357
1358
1359
1360/************************************************
1361 * Traffic classes manipulation. *
1362 ************************************************/
1363
1364
1365
1366static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1367{
1368 struct net *net = sock_net(skb->sk);
1369 struct tcmsg *tcm = NLMSG_DATA(n);
1370 struct nlattr *tca[TCA_MAX + 1];
1371 struct net_device *dev;
1372 struct Qdisc *q = NULL;
1373 const struct Qdisc_class_ops *cops;
1374 unsigned long cl = 0;
1375 unsigned long new_cl;
1376 u32 pid = tcm->tcm_parent;
1377 u32 clid = tcm->tcm_handle;
1378 u32 qid = TC_H_MAJ(clid);
1379 int err;
1380
1381 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1382 if (!dev)
1383 return -ENODEV;
1384
1385 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1386 if (err < 0)
1387 return err;
1388
1389 /*
1390 parent == TC_H_UNSPEC - unspecified parent.
1391 parent == TC_H_ROOT - class is root, which has no parent.
1392 parent == X:0 - parent is root class.
1393 parent == X:Y - parent is a node in hierarchy.
1394 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
1395
1396 handle == 0:0 - generate handle from kernel pool.
1397 handle == 0:Y - class is X:Y, where X:0 is qdisc.
1398 handle == X:Y - clear.
1399 handle == X:0 - root class.
1400 */
1401
1402 /* Step 1. Determine qdisc handle X:0 */
1403
1404 if (pid != TC_H_ROOT) {
1405 u32 qid1 = TC_H_MAJ(pid);
1406
1407 if (qid && qid1) {
1408 /* If both majors are known, they must be identical. */
1409 if (qid != qid1)
1410 return -EINVAL;
1411 } else if (qid1) {
1412 qid = qid1;
1413 } else if (qid == 0)
1414 qid = dev->qdisc->handle;
1415
1416 /* Now qid is genuine qdisc handle consistent
1417 * both with parent and child.
1418 *
1419 * TC_H_MAJ(pid) still may be unspecified, complete it now.
1420 */
1421 if (pid)
1422 pid = TC_H_MAKE(qid, pid);
1423 } else {
1424 if (qid == 0)
1425 qid = dev->qdisc->handle;
1426 }
1427
1428 /* OK. Locate qdisc */
1429 q = qdisc_lookup(dev, qid);
1430 if (!q)
1431 return -ENOENT;
1432
1433 /* An check that it supports classes */
1434 cops = q->ops->cl_ops;
1435 if (cops == NULL)
1436 return -EINVAL;
1437
1438 /* Now try to get class */
1439 if (clid == 0) {
1440 if (pid == TC_H_ROOT)
1441 clid = qid;
1442 } else
1443 clid = TC_H_MAKE(qid, clid);
1444
1445 if (clid)
1446 cl = cops->get(q, clid);
1447
1448 if (cl == 0) {
1449 err = -ENOENT;
1450 if (n->nlmsg_type != RTM_NEWTCLASS ||
1451 !(n->nlmsg_flags & NLM_F_CREATE))
1452 goto out;
1453 } else {
1454 switch (n->nlmsg_type) {
1455 case RTM_NEWTCLASS:
1456 err = -EEXIST;
1457 if (n->nlmsg_flags & NLM_F_EXCL)
1458 goto out;
1459 break;
1460 case RTM_DELTCLASS:
1461 err = -EOPNOTSUPP;
1462 if (cops->delete)
1463 err = cops->delete(q, cl);
1464 if (err == 0)
1465 tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS);
1466 goto out;
1467 case RTM_GETTCLASS:
1468 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
1469 goto out;
1470 default:
1471 err = -EINVAL;
1472 goto out;
1473 }
1474 }
1475
1476 new_cl = cl;
1477 err = -EOPNOTSUPP;
1478 if (cops->change)
1479 err = cops->change(q, clid, pid, tca, &new_cl);
1480 if (err == 0)
1481 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
1482
1483out:
1484 if (cl)
1485 cops->put(q, cl);
1486
1487 return err;
1488}
1489
1490
1491static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1492 unsigned long cl,
1493 u32 pid, u32 seq, u16 flags, int event)
1494{
1495 struct tcmsg *tcm;
1496 struct nlmsghdr *nlh;
1497 unsigned char *b = skb_tail_pointer(skb);
1498 struct gnet_dump d;
1499 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1500
1501 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
1502 tcm = NLMSG_DATA(nlh);
1503 tcm->tcm_family = AF_UNSPEC;
1504 tcm->tcm__pad1 = 0;
1505 tcm->tcm__pad2 = 0;
1506 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1507 tcm->tcm_parent = q->handle;
1508 tcm->tcm_handle = q->handle;
1509 tcm->tcm_info = 0;
1510 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1511 goto nla_put_failure;
1512 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1513 goto nla_put_failure;
1514
1515 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1516 qdisc_root_sleeping_lock(q), &d) < 0)
1517 goto nla_put_failure;
1518
1519 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1520 goto nla_put_failure;
1521
1522 if (gnet_stats_finish_copy(&d) < 0)
1523 goto nla_put_failure;
1524
1525 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1526 return skb->len;
1527
1528nlmsg_failure:
1529nla_put_failure:
1530 nlmsg_trim(skb, b);
1531 return -1;
1532}
1533
1534static int tclass_notify(struct net *net, struct sk_buff *oskb,
1535 struct nlmsghdr *n, struct Qdisc *q,
1536 unsigned long cl, int event)
1537{
1538 struct sk_buff *skb;
1539 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1540
1541 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1542 if (!skb)
1543 return -ENOBUFS;
1544
1545 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) {
1546 kfree_skb(skb);
1547 return -EINVAL;
1548 }
1549
1550 return rtnetlink_send(skb, net, pid, RTNLGRP_TC,
1551 n->nlmsg_flags & NLM_F_ECHO);
1552}
1553
1554struct qdisc_dump_args {
1555 struct qdisc_walker w;
1556 struct sk_buff *skb;
1557 struct netlink_callback *cb;
1558};
1559
1560static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
1561{
1562 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
1563
1564 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid,
1565 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
1566}
1567
1568static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
1569 struct tcmsg *tcm, struct netlink_callback *cb,
1570 int *t_p, int s_t)
1571{
1572 struct qdisc_dump_args arg;
1573
1574 if (tc_qdisc_dump_ignore(q) ||
1575 *t_p < s_t || !q->ops->cl_ops ||
1576 (tcm->tcm_parent &&
1577 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
1578 (*t_p)++;
1579 return 0;
1580 }
1581 if (*t_p > s_t)
1582 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
1583 arg.w.fn = qdisc_class_dump;
1584 arg.skb = skb;
1585 arg.cb = cb;
1586 arg.w.stop = 0;
1587 arg.w.skip = cb->args[1];
1588 arg.w.count = 0;
1589 q->ops->cl_ops->walk(q, &arg.w);
1590 cb->args[1] = arg.w.count;
1591 if (arg.w.stop)
1592 return -1;
1593 (*t_p)++;
1594 return 0;
1595}
1596
1597static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
1598 struct tcmsg *tcm, struct netlink_callback *cb,
1599 int *t_p, int s_t)
1600{
1601 struct Qdisc *q;
1602
1603 if (!root)
1604 return 0;
1605
1606 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
1607 return -1;
1608
1609 list_for_each_entry(q, &root->list, list) {
1610 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
1611 return -1;
1612 }
1613
1614 return 0;
1615}
1616
1617static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
1618{
1619 struct tcmsg *tcm = (struct tcmsg *)NLMSG_DATA(cb->nlh);
1620 struct net *net = sock_net(skb->sk);
1621 struct netdev_queue *dev_queue;
1622 struct net_device *dev;
1623 int t, s_t;
1624
1625 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
1626 return 0;
1627 dev = dev_get_by_index(net, tcm->tcm_ifindex);
1628 if (!dev)
1629 return 0;
1630
1631 s_t = cb->args[0];
1632 t = 0;
1633
1634 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1635 goto done;
1636
1637 dev_queue = dev_ingress_queue(dev);
1638 if (dev_queue &&
1639 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
1640 &t, s_t) < 0)
1641 goto done;
1642
1643done:
1644 cb->args[0] = t;
1645
1646 dev_put(dev);
1647 return skb->len;
1648}
1649
1650/* Main classifier routine: scans classifier chain attached
1651 * to this qdisc, (optionally) tests for protocol and asks
1652 * specific classifiers.
1653 */
1654int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
1655 struct tcf_result *res)
1656{
1657 __be16 protocol = skb->protocol;
1658 int err;
1659
1660 for (; tp; tp = tp->next) {
1661 if (tp->protocol != protocol &&
1662 tp->protocol != htons(ETH_P_ALL))
1663 continue;
1664 err = tp->classify(skb, tp, res);
1665
1666 if (err >= 0) {
1667#ifdef CONFIG_NET_CLS_ACT
1668 if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
1669 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
1670#endif
1671 return err;
1672 }
1673 }
1674 return -1;
1675}
1676EXPORT_SYMBOL(tc_classify_compat);
1677
1678int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1679 struct tcf_result *res)
1680{
1681 int err = 0;
1682#ifdef CONFIG_NET_CLS_ACT
1683 const struct tcf_proto *otp = tp;
1684reclassify:
1685#endif
1686
1687 err = tc_classify_compat(skb, tp, res);
1688#ifdef CONFIG_NET_CLS_ACT
1689 if (err == TC_ACT_RECLASSIFY) {
1690 u32 verd = G_TC_VERD(skb->tc_verd);
1691 tp = otp;
1692
1693 if (verd++ >= MAX_REC_LOOP) {
1694 net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n",
1695 tp->q->ops->id,
1696 tp->prio & 0xffff,
1697 ntohs(tp->protocol));
1698 return TC_ACT_SHOT;
1699 }
1700 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
1701 goto reclassify;
1702 }
1703#endif
1704 return err;
1705}
1706EXPORT_SYMBOL(tc_classify);
1707
1708void tcf_destroy(struct tcf_proto *tp)
1709{
1710 tp->ops->destroy(tp);
1711 module_put(tp->ops->owner);
1712 kfree(tp);
1713}
1714
1715void tcf_destroy_chain(struct tcf_proto **fl)
1716{
1717 struct tcf_proto *tp;
1718
1719 while ((tp = *fl) != NULL) {
1720 *fl = tp->next;
1721 tcf_destroy(tp);
1722 }
1723}
1724EXPORT_SYMBOL(tcf_destroy_chain);
1725
1726#ifdef CONFIG_PROC_FS
1727static int psched_show(struct seq_file *seq, void *v)
1728{
1729 struct timespec ts;
1730
1731 hrtimer_get_res(CLOCK_MONOTONIC, &ts);
1732 seq_printf(seq, "%08x %08x %08x %08x\n",
1733 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1734 1000000,
1735 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
1736
1737 return 0;
1738}
1739
1740static int psched_open(struct inode *inode, struct file *file)
1741{
1742 return single_open(file, psched_show, NULL);
1743}
1744
1745static const struct file_operations psched_fops = {
1746 .owner = THIS_MODULE,
1747 .open = psched_open,
1748 .read = seq_read,
1749 .llseek = seq_lseek,
1750 .release = single_release,
1751};
1752
1753static int __net_init psched_net_init(struct net *net)
1754{
1755 struct proc_dir_entry *e;
1756
1757 e = proc_net_fops_create(net, "psched", 0, &psched_fops);
1758 if (e == NULL)
1759 return -ENOMEM;
1760
1761 return 0;
1762}
1763
1764static void __net_exit psched_net_exit(struct net *net)
1765{
1766 proc_net_remove(net, "psched");
1767}
1768#else
1769static int __net_init psched_net_init(struct net *net)
1770{
1771 return 0;
1772}
1773
1774static void __net_exit psched_net_exit(struct net *net)
1775{
1776}
1777#endif
1778
1779static struct pernet_operations psched_net_ops = {
1780 .init = psched_net_init,
1781 .exit = psched_net_exit,
1782};
1783
1784static int __init pktsched_init(void)
1785{
1786 int err;
1787
1788 err = register_pernet_subsys(&psched_net_ops);
1789 if (err) {
1790 pr_err("pktsched_init: "
1791 "cannot initialize per netns operations\n");
1792 return err;
1793 }
1794
1795 register_qdisc(&pfifo_qdisc_ops);
1796 register_qdisc(&bfifo_qdisc_ops);
1797 register_qdisc(&pfifo_head_drop_qdisc_ops);
1798 register_qdisc(&mq_qdisc_ops);
1799
1800 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
1801 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
1802 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, NULL);
1803 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
1804 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1805 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, NULL);
1806
1807 return 0;
1808}
1809
1810subsys_initcall(pktsched_init);
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
38static int qdisc_notify(struct net *net, struct sk_buff *oskb,
39 struct nlmsghdr *n, u32 clid,
40 struct Qdisc *old, struct Qdisc *new);
41static 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. */
126static DEFINE_RWLOCK(qdisc_mod_lock);
127
128
129/************************************************
130 * Queueing disciplines manipulation. *
131 ************************************************/
132
133
134/* The list of all installed queueing disciplines. */
135
136static struct Qdisc_ops *qdisc_base;
137
138/* Register/unregister queueing discipline */
139
140int 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;
174out:
175 write_unlock(&qdisc_mod_lock);
176 return rc;
177
178out_einval:
179 rc = -EINVAL;
180 goto out;
181}
182EXPORT_SYMBOL(register_qdisc);
183
184int 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}
201EXPORT_SYMBOL(unregister_qdisc);
202
203/* Get default qdisc if not otherwise specified */
204void qdisc_get_default(char *name, size_t len)
205{
206 read_lock(&qdisc_mod_lock);
207 strlcpy(name, default_qdisc_ops->id, len);
208 read_unlock(&qdisc_mod_lock);
209}
210
211static struct Qdisc_ops *qdisc_lookup_default(const char *name)
212{
213 struct Qdisc_ops *q = NULL;
214
215 for (q = qdisc_base; q; q = q->next) {
216 if (!strcmp(name, q->id)) {
217 if (!try_module_get(q->owner))
218 q = NULL;
219 break;
220 }
221 }
222
223 return q;
224}
225
226/* Set new default qdisc to use */
227int qdisc_set_default(const char *name)
228{
229 const struct Qdisc_ops *ops;
230
231 if (!capable(CAP_NET_ADMIN))
232 return -EPERM;
233
234 write_lock(&qdisc_mod_lock);
235 ops = qdisc_lookup_default(name);
236 if (!ops) {
237 /* Not found, drop lock and try to load module */
238 write_unlock(&qdisc_mod_lock);
239 request_module("sch_%s", name);
240 write_lock(&qdisc_mod_lock);
241
242 ops = qdisc_lookup_default(name);
243 }
244
245 if (ops) {
246 /* Set new default */
247 module_put(default_qdisc_ops->owner);
248 default_qdisc_ops = ops;
249 }
250 write_unlock(&qdisc_mod_lock);
251
252 return ops ? 0 : -ENOENT;
253}
254
255/* We know handle. Find qdisc among all qdisc's attached to device
256 (root qdisc, all its children, children of children etc.)
257 */
258
259static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
260{
261 struct Qdisc *q;
262
263 if (!(root->flags & TCQ_F_BUILTIN) &&
264 root->handle == handle)
265 return root;
266
267 list_for_each_entry(q, &root->list, list) {
268 if (q->handle == handle)
269 return q;
270 }
271 return NULL;
272}
273
274void qdisc_list_add(struct Qdisc *q)
275{
276 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
277 struct Qdisc *root = qdisc_dev(q)->qdisc;
278
279 WARN_ON_ONCE(root == &noop_qdisc);
280 list_add_tail(&q->list, &root->list);
281 }
282}
283EXPORT_SYMBOL(qdisc_list_add);
284
285void qdisc_list_del(struct Qdisc *q)
286{
287 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
288 list_del(&q->list);
289}
290EXPORT_SYMBOL(qdisc_list_del);
291
292struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
293{
294 struct Qdisc *q;
295
296 q = qdisc_match_from_root(dev->qdisc, handle);
297 if (q)
298 goto out;
299
300 if (dev_ingress_queue(dev))
301 q = qdisc_match_from_root(
302 dev_ingress_queue(dev)->qdisc_sleeping,
303 handle);
304out:
305 return q;
306}
307
308static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
309{
310 unsigned long cl;
311 struct Qdisc *leaf;
312 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
313
314 if (cops == NULL)
315 return NULL;
316 cl = cops->get(p, classid);
317
318 if (cl == 0)
319 return NULL;
320 leaf = cops->leaf(p, cl);
321 cops->put(p, cl);
322 return leaf;
323}
324
325/* Find queueing discipline by name */
326
327static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
328{
329 struct Qdisc_ops *q = NULL;
330
331 if (kind) {
332 read_lock(&qdisc_mod_lock);
333 for (q = qdisc_base; q; q = q->next) {
334 if (nla_strcmp(kind, q->id) == 0) {
335 if (!try_module_get(q->owner))
336 q = NULL;
337 break;
338 }
339 }
340 read_unlock(&qdisc_mod_lock);
341 }
342 return q;
343}
344
345/* The linklayer setting were not transferred from iproute2, in older
346 * versions, and the rate tables lookup systems have been dropped in
347 * the kernel. To keep backward compatible with older iproute2 tc
348 * utils, we detect the linklayer setting by detecting if the rate
349 * table were modified.
350 *
351 * For linklayer ATM table entries, the rate table will be aligned to
352 * 48 bytes, thus some table entries will contain the same value. The
353 * mpu (min packet unit) is also encoded into the old rate table, thus
354 * starting from the mpu, we find low and high table entries for
355 * mapping this cell. If these entries contain the same value, when
356 * the rate tables have been modified for linklayer ATM.
357 *
358 * This is done by rounding mpu to the nearest 48 bytes cell/entry,
359 * and then roundup to the next cell, calc the table entry one below,
360 * and compare.
361 */
362static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab)
363{
364 int low = roundup(r->mpu, 48);
365 int high = roundup(low+1, 48);
366 int cell_low = low >> r->cell_log;
367 int cell_high = (high >> r->cell_log) - 1;
368
369 /* rtab is too inaccurate at rates > 100Mbit/s */
370 if ((r->rate > (100000000/8)) || (rtab[0] == 0)) {
371 pr_debug("TC linklayer: Giving up ATM detection\n");
372 return TC_LINKLAYER_ETHERNET;
373 }
374
375 if ((cell_high > cell_low) && (cell_high < 256)
376 && (rtab[cell_low] == rtab[cell_high])) {
377 pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n",
378 cell_low, cell_high, rtab[cell_high]);
379 return TC_LINKLAYER_ATM;
380 }
381 return TC_LINKLAYER_ETHERNET;
382}
383
384static struct qdisc_rate_table *qdisc_rtab_list;
385
386struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
387{
388 struct qdisc_rate_table *rtab;
389
390 if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
391 nla_len(tab) != TC_RTAB_SIZE)
392 return NULL;
393
394 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
395 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
396 !memcmp(&rtab->data, nla_data(tab), 1024)) {
397 rtab->refcnt++;
398 return rtab;
399 }
400 }
401
402 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
403 if (rtab) {
404 rtab->rate = *r;
405 rtab->refcnt = 1;
406 memcpy(rtab->data, nla_data(tab), 1024);
407 if (r->linklayer == TC_LINKLAYER_UNAWARE)
408 r->linklayer = __detect_linklayer(r, rtab->data);
409 rtab->next = qdisc_rtab_list;
410 qdisc_rtab_list = rtab;
411 }
412 return rtab;
413}
414EXPORT_SYMBOL(qdisc_get_rtab);
415
416void qdisc_put_rtab(struct qdisc_rate_table *tab)
417{
418 struct qdisc_rate_table *rtab, **rtabp;
419
420 if (!tab || --tab->refcnt)
421 return;
422
423 for (rtabp = &qdisc_rtab_list;
424 (rtab = *rtabp) != NULL;
425 rtabp = &rtab->next) {
426 if (rtab == tab) {
427 *rtabp = rtab->next;
428 kfree(rtab);
429 return;
430 }
431 }
432}
433EXPORT_SYMBOL(qdisc_put_rtab);
434
435static LIST_HEAD(qdisc_stab_list);
436static DEFINE_SPINLOCK(qdisc_stab_lock);
437
438static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
439 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) },
440 [TCA_STAB_DATA] = { .type = NLA_BINARY },
441};
442
443static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
444{
445 struct nlattr *tb[TCA_STAB_MAX + 1];
446 struct qdisc_size_table *stab;
447 struct tc_sizespec *s;
448 unsigned int tsize = 0;
449 u16 *tab = NULL;
450 int err;
451
452 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy);
453 if (err < 0)
454 return ERR_PTR(err);
455 if (!tb[TCA_STAB_BASE])
456 return ERR_PTR(-EINVAL);
457
458 s = nla_data(tb[TCA_STAB_BASE]);
459
460 if (s->tsize > 0) {
461 if (!tb[TCA_STAB_DATA])
462 return ERR_PTR(-EINVAL);
463 tab = nla_data(tb[TCA_STAB_DATA]);
464 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
465 }
466
467 if (tsize != s->tsize || (!tab && tsize > 0))
468 return ERR_PTR(-EINVAL);
469
470 spin_lock(&qdisc_stab_lock);
471
472 list_for_each_entry(stab, &qdisc_stab_list, list) {
473 if (memcmp(&stab->szopts, s, sizeof(*s)))
474 continue;
475 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16)))
476 continue;
477 stab->refcnt++;
478 spin_unlock(&qdisc_stab_lock);
479 return stab;
480 }
481
482 spin_unlock(&qdisc_stab_lock);
483
484 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
485 if (!stab)
486 return ERR_PTR(-ENOMEM);
487
488 stab->refcnt = 1;
489 stab->szopts = *s;
490 if (tsize > 0)
491 memcpy(stab->data, tab, tsize * sizeof(u16));
492
493 spin_lock(&qdisc_stab_lock);
494 list_add_tail(&stab->list, &qdisc_stab_list);
495 spin_unlock(&qdisc_stab_lock);
496
497 return stab;
498}
499
500static void stab_kfree_rcu(struct rcu_head *head)
501{
502 kfree(container_of(head, struct qdisc_size_table, rcu));
503}
504
505void qdisc_put_stab(struct qdisc_size_table *tab)
506{
507 if (!tab)
508 return;
509
510 spin_lock(&qdisc_stab_lock);
511
512 if (--tab->refcnt == 0) {
513 list_del(&tab->list);
514 call_rcu_bh(&tab->rcu, stab_kfree_rcu);
515 }
516
517 spin_unlock(&qdisc_stab_lock);
518}
519EXPORT_SYMBOL(qdisc_put_stab);
520
521static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
522{
523 struct nlattr *nest;
524
525 nest = nla_nest_start(skb, TCA_STAB);
526 if (nest == NULL)
527 goto nla_put_failure;
528 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
529 goto nla_put_failure;
530 nla_nest_end(skb, nest);
531
532 return skb->len;
533
534nla_put_failure:
535 return -1;
536}
537
538void __qdisc_calculate_pkt_len(struct sk_buff *skb, const struct qdisc_size_table *stab)
539{
540 int pkt_len, slot;
541
542 pkt_len = skb->len + stab->szopts.overhead;
543 if (unlikely(!stab->szopts.tsize))
544 goto out;
545
546 slot = pkt_len + stab->szopts.cell_align;
547 if (unlikely(slot < 0))
548 slot = 0;
549
550 slot >>= stab->szopts.cell_log;
551 if (likely(slot < stab->szopts.tsize))
552 pkt_len = stab->data[slot];
553 else
554 pkt_len = stab->data[stab->szopts.tsize - 1] *
555 (slot / stab->szopts.tsize) +
556 stab->data[slot % stab->szopts.tsize];
557
558 pkt_len <<= stab->szopts.size_log;
559out:
560 if (unlikely(pkt_len < 1))
561 pkt_len = 1;
562 qdisc_skb_cb(skb)->pkt_len = pkt_len;
563}
564EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
565
566void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc)
567{
568 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
569 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
570 txt, qdisc->ops->id, qdisc->handle >> 16);
571 qdisc->flags |= TCQ_F_WARN_NONWC;
572 }
573}
574EXPORT_SYMBOL(qdisc_warn_nonwc);
575
576static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
577{
578 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
579 timer);
580
581 qdisc_unthrottled(wd->qdisc);
582 __netif_schedule(qdisc_root(wd->qdisc));
583
584 return HRTIMER_NORESTART;
585}
586
587void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
588{
589 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
590 wd->timer.function = qdisc_watchdog;
591 wd->qdisc = qdisc;
592}
593EXPORT_SYMBOL(qdisc_watchdog_init);
594
595void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires)
596{
597 if (test_bit(__QDISC_STATE_DEACTIVATED,
598 &qdisc_root_sleeping(wd->qdisc)->state))
599 return;
600
601 qdisc_throttled(wd->qdisc);
602
603 hrtimer_start(&wd->timer,
604 ns_to_ktime(expires),
605 HRTIMER_MODE_ABS);
606}
607EXPORT_SYMBOL(qdisc_watchdog_schedule_ns);
608
609void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
610{
611 hrtimer_cancel(&wd->timer);
612 qdisc_unthrottled(wd->qdisc);
613}
614EXPORT_SYMBOL(qdisc_watchdog_cancel);
615
616static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
617{
618 unsigned int size = n * sizeof(struct hlist_head), i;
619 struct hlist_head *h;
620
621 if (size <= PAGE_SIZE)
622 h = kmalloc(size, GFP_KERNEL);
623 else
624 h = (struct hlist_head *)
625 __get_free_pages(GFP_KERNEL, get_order(size));
626
627 if (h != NULL) {
628 for (i = 0; i < n; i++)
629 INIT_HLIST_HEAD(&h[i]);
630 }
631 return h;
632}
633
634static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
635{
636 unsigned int size = n * sizeof(struct hlist_head);
637
638 if (size <= PAGE_SIZE)
639 kfree(h);
640 else
641 free_pages((unsigned long)h, get_order(size));
642}
643
644void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
645{
646 struct Qdisc_class_common *cl;
647 struct hlist_node *next;
648 struct hlist_head *nhash, *ohash;
649 unsigned int nsize, nmask, osize;
650 unsigned int i, h;
651
652 /* Rehash when load factor exceeds 0.75 */
653 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
654 return;
655 nsize = clhash->hashsize * 2;
656 nmask = nsize - 1;
657 nhash = qdisc_class_hash_alloc(nsize);
658 if (nhash == NULL)
659 return;
660
661 ohash = clhash->hash;
662 osize = clhash->hashsize;
663
664 sch_tree_lock(sch);
665 for (i = 0; i < osize; i++) {
666 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
667 h = qdisc_class_hash(cl->classid, nmask);
668 hlist_add_head(&cl->hnode, &nhash[h]);
669 }
670 }
671 clhash->hash = nhash;
672 clhash->hashsize = nsize;
673 clhash->hashmask = nmask;
674 sch_tree_unlock(sch);
675
676 qdisc_class_hash_free(ohash, osize);
677}
678EXPORT_SYMBOL(qdisc_class_hash_grow);
679
680int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
681{
682 unsigned int size = 4;
683
684 clhash->hash = qdisc_class_hash_alloc(size);
685 if (clhash->hash == NULL)
686 return -ENOMEM;
687 clhash->hashsize = size;
688 clhash->hashmask = size - 1;
689 clhash->hashelems = 0;
690 return 0;
691}
692EXPORT_SYMBOL(qdisc_class_hash_init);
693
694void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
695{
696 qdisc_class_hash_free(clhash->hash, clhash->hashsize);
697}
698EXPORT_SYMBOL(qdisc_class_hash_destroy);
699
700void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
701 struct Qdisc_class_common *cl)
702{
703 unsigned int h;
704
705 INIT_HLIST_NODE(&cl->hnode);
706 h = qdisc_class_hash(cl->classid, clhash->hashmask);
707 hlist_add_head(&cl->hnode, &clhash->hash[h]);
708 clhash->hashelems++;
709}
710EXPORT_SYMBOL(qdisc_class_hash_insert);
711
712void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
713 struct Qdisc_class_common *cl)
714{
715 hlist_del(&cl->hnode);
716 clhash->hashelems--;
717}
718EXPORT_SYMBOL(qdisc_class_hash_remove);
719
720/* Allocate an unique handle from space managed by kernel
721 * Possible range is [8000-FFFF]:0000 (0x8000 values)
722 */
723static u32 qdisc_alloc_handle(struct net_device *dev)
724{
725 int i = 0x8000;
726 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
727
728 do {
729 autohandle += TC_H_MAKE(0x10000U, 0);
730 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
731 autohandle = TC_H_MAKE(0x80000000U, 0);
732 if (!qdisc_lookup(dev, autohandle))
733 return autohandle;
734 cond_resched();
735 } while (--i > 0);
736
737 return 0;
738}
739
740void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
741{
742 const struct Qdisc_class_ops *cops;
743 unsigned long cl;
744 u32 parentid;
745 int drops;
746
747 if (n == 0)
748 return;
749 drops = max_t(int, n, 0);
750 while ((parentid = sch->parent)) {
751 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
752 return;
753
754 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
755 if (sch == NULL) {
756 WARN_ON(parentid != TC_H_ROOT);
757 return;
758 }
759 cops = sch->ops->cl_ops;
760 if (cops->qlen_notify) {
761 cl = cops->get(sch, parentid);
762 cops->qlen_notify(sch, cl);
763 cops->put(sch, cl);
764 }
765 sch->q.qlen -= n;
766 sch->qstats.drops += drops;
767 }
768}
769EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
770
771static void notify_and_destroy(struct net *net, struct sk_buff *skb,
772 struct nlmsghdr *n, u32 clid,
773 struct Qdisc *old, struct Qdisc *new)
774{
775 if (new || old)
776 qdisc_notify(net, skb, n, clid, old, new);
777
778 if (old)
779 qdisc_destroy(old);
780}
781
782/* Graft qdisc "new" to class "classid" of qdisc "parent" or
783 * to device "dev".
784 *
785 * When appropriate send a netlink notification using 'skb'
786 * and "n".
787 *
788 * On success, destroy old qdisc.
789 */
790
791static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
792 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
793 struct Qdisc *new, struct Qdisc *old)
794{
795 struct Qdisc *q = old;
796 struct net *net = dev_net(dev);
797 int err = 0;
798
799 if (parent == NULL) {
800 unsigned int i, num_q, ingress;
801
802 ingress = 0;
803 num_q = dev->num_tx_queues;
804 if ((q && q->flags & TCQ_F_INGRESS) ||
805 (new && new->flags & TCQ_F_INGRESS)) {
806 num_q = 1;
807 ingress = 1;
808 if (!dev_ingress_queue(dev))
809 return -ENOENT;
810 }
811
812 if (dev->flags & IFF_UP)
813 dev_deactivate(dev);
814
815 if (new && new->ops->attach) {
816 new->ops->attach(new);
817 num_q = 0;
818 }
819
820 for (i = 0; i < num_q; i++) {
821 struct netdev_queue *dev_queue = dev_ingress_queue(dev);
822
823 if (!ingress)
824 dev_queue = netdev_get_tx_queue(dev, i);
825
826 old = dev_graft_qdisc(dev_queue, new);
827 if (new && i > 0)
828 atomic_inc(&new->refcnt);
829
830 if (!ingress)
831 qdisc_destroy(old);
832 }
833
834 if (!ingress) {
835 notify_and_destroy(net, skb, n, classid,
836 dev->qdisc, new);
837 if (new && !new->ops->attach)
838 atomic_inc(&new->refcnt);
839 dev->qdisc = new ? : &noop_qdisc;
840 } else {
841 notify_and_destroy(net, skb, n, classid, old, new);
842 }
843
844 if (dev->flags & IFF_UP)
845 dev_activate(dev);
846 } else {
847 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
848
849 err = -EOPNOTSUPP;
850 if (cops && cops->graft) {
851 unsigned long cl = cops->get(parent, classid);
852 if (cl) {
853 err = cops->graft(parent, cl, new, &old);
854 cops->put(parent, cl);
855 } else
856 err = -ENOENT;
857 }
858 if (!err)
859 notify_and_destroy(net, skb, n, classid, old, new);
860 }
861 return err;
862}
863
864/* lockdep annotation is needed for ingress; egress gets it only for name */
865static struct lock_class_key qdisc_tx_lock;
866static struct lock_class_key qdisc_rx_lock;
867
868/*
869 Allocate and initialize new qdisc.
870
871 Parameters are passed via opt.
872 */
873
874static struct Qdisc *
875qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
876 struct Qdisc *p, u32 parent, u32 handle,
877 struct nlattr **tca, int *errp)
878{
879 int err;
880 struct nlattr *kind = tca[TCA_KIND];
881 struct Qdisc *sch;
882 struct Qdisc_ops *ops;
883 struct qdisc_size_table *stab;
884
885 ops = qdisc_lookup_ops(kind);
886#ifdef CONFIG_MODULES
887 if (ops == NULL && kind != NULL) {
888 char name[IFNAMSIZ];
889 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
890 /* We dropped the RTNL semaphore in order to
891 * perform the module load. So, even if we
892 * succeeded in loading the module we have to
893 * tell the caller to replay the request. We
894 * indicate this using -EAGAIN.
895 * We replay the request because the device may
896 * go away in the mean time.
897 */
898 rtnl_unlock();
899 request_module("sch_%s", name);
900 rtnl_lock();
901 ops = qdisc_lookup_ops(kind);
902 if (ops != NULL) {
903 /* We will try again qdisc_lookup_ops,
904 * so don't keep a reference.
905 */
906 module_put(ops->owner);
907 err = -EAGAIN;
908 goto err_out;
909 }
910 }
911 }
912#endif
913
914 err = -ENOENT;
915 if (ops == NULL)
916 goto err_out;
917
918 sch = qdisc_alloc(dev_queue, ops);
919 if (IS_ERR(sch)) {
920 err = PTR_ERR(sch);
921 goto err_out2;
922 }
923
924 sch->parent = parent;
925
926 if (handle == TC_H_INGRESS) {
927 sch->flags |= TCQ_F_INGRESS;
928 handle = TC_H_MAKE(TC_H_INGRESS, 0);
929 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
930 } else {
931 if (handle == 0) {
932 handle = qdisc_alloc_handle(dev);
933 err = -ENOMEM;
934 if (handle == 0)
935 goto err_out3;
936 }
937 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
938 if (!netif_is_multiqueue(dev))
939 sch->flags |= TCQ_F_ONETXQUEUE;
940 }
941
942 sch->handle = handle;
943
944 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
945 if (tca[TCA_STAB]) {
946 stab = qdisc_get_stab(tca[TCA_STAB]);
947 if (IS_ERR(stab)) {
948 err = PTR_ERR(stab);
949 goto err_out4;
950 }
951 rcu_assign_pointer(sch->stab, stab);
952 }
953 if (tca[TCA_RATE]) {
954 spinlock_t *root_lock;
955
956 err = -EOPNOTSUPP;
957 if (sch->flags & TCQ_F_MQROOT)
958 goto err_out4;
959
960 if ((sch->parent != TC_H_ROOT) &&
961 !(sch->flags & TCQ_F_INGRESS) &&
962 (!p || !(p->flags & TCQ_F_MQROOT)))
963 root_lock = qdisc_root_sleeping_lock(sch);
964 else
965 root_lock = qdisc_lock(sch);
966
967 err = gen_new_estimator(&sch->bstats, &sch->rate_est,
968 root_lock, tca[TCA_RATE]);
969 if (err)
970 goto err_out4;
971 }
972
973 qdisc_list_add(sch);
974
975 return sch;
976 }
977err_out3:
978 dev_put(dev);
979 kfree((char *) sch - sch->padded);
980err_out2:
981 module_put(ops->owner);
982err_out:
983 *errp = err;
984 return NULL;
985
986err_out4:
987 /*
988 * Any broken qdiscs that would require a ops->reset() here?
989 * The qdisc was never in action so it shouldn't be necessary.
990 */
991 qdisc_put_stab(rtnl_dereference(sch->stab));
992 if (ops->destroy)
993 ops->destroy(sch);
994 goto err_out3;
995}
996
997static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
998{
999 struct qdisc_size_table *ostab, *stab = NULL;
1000 int err = 0;
1001
1002 if (tca[TCA_OPTIONS]) {
1003 if (sch->ops->change == NULL)
1004 return -EINVAL;
1005 err = sch->ops->change(sch, tca[TCA_OPTIONS]);
1006 if (err)
1007 return err;
1008 }
1009
1010 if (tca[TCA_STAB]) {
1011 stab = qdisc_get_stab(tca[TCA_STAB]);
1012 if (IS_ERR(stab))
1013 return PTR_ERR(stab);
1014 }
1015
1016 ostab = rtnl_dereference(sch->stab);
1017 rcu_assign_pointer(sch->stab, stab);
1018 qdisc_put_stab(ostab);
1019
1020 if (tca[TCA_RATE]) {
1021 /* NB: ignores errors from replace_estimator
1022 because change can't be undone. */
1023 if (sch->flags & TCQ_F_MQROOT)
1024 goto out;
1025 gen_replace_estimator(&sch->bstats, &sch->rate_est,
1026 qdisc_root_sleeping_lock(sch),
1027 tca[TCA_RATE]);
1028 }
1029out:
1030 return 0;
1031}
1032
1033struct check_loop_arg {
1034 struct qdisc_walker w;
1035 struct Qdisc *p;
1036 int depth;
1037};
1038
1039static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
1040
1041static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
1042{
1043 struct check_loop_arg arg;
1044
1045 if (q->ops->cl_ops == NULL)
1046 return 0;
1047
1048 arg.w.stop = arg.w.skip = arg.w.count = 0;
1049 arg.w.fn = check_loop_fn;
1050 arg.depth = depth;
1051 arg.p = p;
1052 q->ops->cl_ops->walk(q, &arg.w);
1053 return arg.w.stop ? -ELOOP : 0;
1054}
1055
1056static int
1057check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
1058{
1059 struct Qdisc *leaf;
1060 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1061 struct check_loop_arg *arg = (struct check_loop_arg *)w;
1062
1063 leaf = cops->leaf(q, cl);
1064 if (leaf) {
1065 if (leaf == arg->p || arg->depth > 7)
1066 return -ELOOP;
1067 return check_loop(leaf, arg->p, arg->depth + 1);
1068 }
1069 return 0;
1070}
1071
1072/*
1073 * Delete/get qdisc.
1074 */
1075
1076static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
1077{
1078 struct net *net = sock_net(skb->sk);
1079 struct tcmsg *tcm = nlmsg_data(n);
1080 struct nlattr *tca[TCA_MAX + 1];
1081 struct net_device *dev;
1082 u32 clid;
1083 struct Qdisc *q = NULL;
1084 struct Qdisc *p = NULL;
1085 int err;
1086
1087 if ((n->nlmsg_type != RTM_GETQDISC) && !netlink_capable(skb, CAP_NET_ADMIN))
1088 return -EPERM;
1089
1090 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1091 if (err < 0)
1092 return err;
1093
1094 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1095 if (!dev)
1096 return -ENODEV;
1097
1098 clid = tcm->tcm_parent;
1099 if (clid) {
1100 if (clid != TC_H_ROOT) {
1101 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
1102 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1103 if (!p)
1104 return -ENOENT;
1105 q = qdisc_leaf(p, clid);
1106 } else if (dev_ingress_queue(dev)) {
1107 q = dev_ingress_queue(dev)->qdisc_sleeping;
1108 }
1109 } else {
1110 q = dev->qdisc;
1111 }
1112 if (!q)
1113 return -ENOENT;
1114
1115 if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
1116 return -EINVAL;
1117 } else {
1118 q = qdisc_lookup(dev, tcm->tcm_handle);
1119 if (!q)
1120 return -ENOENT;
1121 }
1122
1123 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1124 return -EINVAL;
1125
1126 if (n->nlmsg_type == RTM_DELQDISC) {
1127 if (!clid)
1128 return -EINVAL;
1129 if (q->handle == 0)
1130 return -ENOENT;
1131 err = qdisc_graft(dev, p, skb, n, clid, NULL, q);
1132 if (err != 0)
1133 return err;
1134 } else {
1135 qdisc_notify(net, skb, n, clid, NULL, q);
1136 }
1137 return 0;
1138}
1139
1140/*
1141 * Create/change qdisc.
1142 */
1143
1144static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n)
1145{
1146 struct net *net = sock_net(skb->sk);
1147 struct tcmsg *tcm;
1148 struct nlattr *tca[TCA_MAX + 1];
1149 struct net_device *dev;
1150 u32 clid;
1151 struct Qdisc *q, *p;
1152 int err;
1153
1154 if (!netlink_capable(skb, CAP_NET_ADMIN))
1155 return -EPERM;
1156
1157replay:
1158 /* Reinit, just in case something touches this. */
1159 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1160 if (err < 0)
1161 return err;
1162
1163 tcm = nlmsg_data(n);
1164 clid = tcm->tcm_parent;
1165 q = p = NULL;
1166
1167 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1168 if (!dev)
1169 return -ENODEV;
1170
1171
1172 if (clid) {
1173 if (clid != TC_H_ROOT) {
1174 if (clid != TC_H_INGRESS) {
1175 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1176 if (!p)
1177 return -ENOENT;
1178 q = qdisc_leaf(p, clid);
1179 } else if (dev_ingress_queue_create(dev)) {
1180 q = dev_ingress_queue(dev)->qdisc_sleeping;
1181 }
1182 } else {
1183 q = dev->qdisc;
1184 }
1185
1186 /* It may be default qdisc, ignore it */
1187 if (q && q->handle == 0)
1188 q = NULL;
1189
1190 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1191 if (tcm->tcm_handle) {
1192 if (q && !(n->nlmsg_flags & NLM_F_REPLACE))
1193 return -EEXIST;
1194 if (TC_H_MIN(tcm->tcm_handle))
1195 return -EINVAL;
1196 q = qdisc_lookup(dev, tcm->tcm_handle);
1197 if (!q)
1198 goto create_n_graft;
1199 if (n->nlmsg_flags & NLM_F_EXCL)
1200 return -EEXIST;
1201 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1202 return -EINVAL;
1203 if (q == p ||
1204 (p && check_loop(q, p, 0)))
1205 return -ELOOP;
1206 atomic_inc(&q->refcnt);
1207 goto graft;
1208 } else {
1209 if (!q)
1210 goto create_n_graft;
1211
1212 /* This magic test requires explanation.
1213 *
1214 * We know, that some child q is already
1215 * attached to this parent and have choice:
1216 * either to change it or to create/graft new one.
1217 *
1218 * 1. We are allowed to create/graft only
1219 * if CREATE and REPLACE flags are set.
1220 *
1221 * 2. If EXCL is set, requestor wanted to say,
1222 * that qdisc tcm_handle is not expected
1223 * to exist, so that we choose create/graft too.
1224 *
1225 * 3. The last case is when no flags are set.
1226 * Alas, it is sort of hole in API, we
1227 * cannot decide what to do unambiguously.
1228 * For now we select create/graft, if
1229 * user gave KIND, which does not match existing.
1230 */
1231 if ((n->nlmsg_flags & NLM_F_CREATE) &&
1232 (n->nlmsg_flags & NLM_F_REPLACE) &&
1233 ((n->nlmsg_flags & NLM_F_EXCL) ||
1234 (tca[TCA_KIND] &&
1235 nla_strcmp(tca[TCA_KIND], q->ops->id))))
1236 goto create_n_graft;
1237 }
1238 }
1239 } else {
1240 if (!tcm->tcm_handle)
1241 return -EINVAL;
1242 q = qdisc_lookup(dev, tcm->tcm_handle);
1243 }
1244
1245 /* Change qdisc parameters */
1246 if (q == NULL)
1247 return -ENOENT;
1248 if (n->nlmsg_flags & NLM_F_EXCL)
1249 return -EEXIST;
1250 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1251 return -EINVAL;
1252 err = qdisc_change(q, tca);
1253 if (err == 0)
1254 qdisc_notify(net, skb, n, clid, NULL, q);
1255 return err;
1256
1257create_n_graft:
1258 if (!(n->nlmsg_flags & NLM_F_CREATE))
1259 return -ENOENT;
1260 if (clid == TC_H_INGRESS) {
1261 if (dev_ingress_queue(dev))
1262 q = qdisc_create(dev, dev_ingress_queue(dev), p,
1263 tcm->tcm_parent, tcm->tcm_parent,
1264 tca, &err);
1265 else
1266 err = -ENOENT;
1267 } else {
1268 struct netdev_queue *dev_queue;
1269
1270 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1271 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1272 else if (p)
1273 dev_queue = p->dev_queue;
1274 else
1275 dev_queue = netdev_get_tx_queue(dev, 0);
1276
1277 q = qdisc_create(dev, dev_queue, p,
1278 tcm->tcm_parent, tcm->tcm_handle,
1279 tca, &err);
1280 }
1281 if (q == NULL) {
1282 if (err == -EAGAIN)
1283 goto replay;
1284 return err;
1285 }
1286
1287graft:
1288 err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
1289 if (err) {
1290 if (q)
1291 qdisc_destroy(q);
1292 return err;
1293 }
1294
1295 return 0;
1296}
1297
1298static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1299 u32 portid, u32 seq, u16 flags, int event)
1300{
1301 struct tcmsg *tcm;
1302 struct nlmsghdr *nlh;
1303 unsigned char *b = skb_tail_pointer(skb);
1304 struct gnet_dump d;
1305 struct qdisc_size_table *stab;
1306
1307 cond_resched();
1308 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1309 if (!nlh)
1310 goto out_nlmsg_trim;
1311 tcm = nlmsg_data(nlh);
1312 tcm->tcm_family = AF_UNSPEC;
1313 tcm->tcm__pad1 = 0;
1314 tcm->tcm__pad2 = 0;
1315 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1316 tcm->tcm_parent = clid;
1317 tcm->tcm_handle = q->handle;
1318 tcm->tcm_info = atomic_read(&q->refcnt);
1319 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1320 goto nla_put_failure;
1321 if (q->ops->dump && q->ops->dump(q, skb) < 0)
1322 goto nla_put_failure;
1323 q->qstats.qlen = q->q.qlen;
1324
1325 stab = rtnl_dereference(q->stab);
1326 if (stab && qdisc_dump_stab(skb, stab) < 0)
1327 goto nla_put_failure;
1328
1329 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1330 qdisc_root_sleeping_lock(q), &d) < 0)
1331 goto nla_put_failure;
1332
1333 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1334 goto nla_put_failure;
1335
1336 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
1337 gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
1338 gnet_stats_copy_queue(&d, &q->qstats) < 0)
1339 goto nla_put_failure;
1340
1341 if (gnet_stats_finish_copy(&d) < 0)
1342 goto nla_put_failure;
1343
1344 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1345 return skb->len;
1346
1347out_nlmsg_trim:
1348nla_put_failure:
1349 nlmsg_trim(skb, b);
1350 return -1;
1351}
1352
1353static bool tc_qdisc_dump_ignore(struct Qdisc *q)
1354{
1355 return (q->flags & TCQ_F_BUILTIN) ? true : false;
1356}
1357
1358static int qdisc_notify(struct net *net, struct sk_buff *oskb,
1359 struct nlmsghdr *n, u32 clid,
1360 struct Qdisc *old, struct Qdisc *new)
1361{
1362 struct sk_buff *skb;
1363 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1364
1365 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1366 if (!skb)
1367 return -ENOBUFS;
1368
1369 if (old && !tc_qdisc_dump_ignore(old)) {
1370 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
1371 0, RTM_DELQDISC) < 0)
1372 goto err_out;
1373 }
1374 if (new && !tc_qdisc_dump_ignore(new)) {
1375 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
1376 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
1377 goto err_out;
1378 }
1379
1380 if (skb->len)
1381 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1382 n->nlmsg_flags & NLM_F_ECHO);
1383
1384err_out:
1385 kfree_skb(skb);
1386 return -EINVAL;
1387}
1388
1389static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1390 struct netlink_callback *cb,
1391 int *q_idx_p, int s_q_idx)
1392{
1393 int ret = 0, q_idx = *q_idx_p;
1394 struct Qdisc *q;
1395
1396 if (!root)
1397 return 0;
1398
1399 q = root;
1400 if (q_idx < s_q_idx) {
1401 q_idx++;
1402 } else {
1403 if (!tc_qdisc_dump_ignore(q) &&
1404 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1405 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1406 goto done;
1407 q_idx++;
1408 }
1409 list_for_each_entry(q, &root->list, list) {
1410 if (q_idx < s_q_idx) {
1411 q_idx++;
1412 continue;
1413 }
1414 if (!tc_qdisc_dump_ignore(q) &&
1415 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1416 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1417 goto done;
1418 q_idx++;
1419 }
1420
1421out:
1422 *q_idx_p = q_idx;
1423 return ret;
1424done:
1425 ret = -1;
1426 goto out;
1427}
1428
1429static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1430{
1431 struct net *net = sock_net(skb->sk);
1432 int idx, q_idx;
1433 int s_idx, s_q_idx;
1434 struct net_device *dev;
1435
1436 s_idx = cb->args[0];
1437 s_q_idx = q_idx = cb->args[1];
1438
1439 idx = 0;
1440 ASSERT_RTNL();
1441 for_each_netdev(net, dev) {
1442 struct netdev_queue *dev_queue;
1443
1444 if (idx < s_idx)
1445 goto cont;
1446 if (idx > s_idx)
1447 s_q_idx = 0;
1448 q_idx = 0;
1449
1450 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1451 goto done;
1452
1453 dev_queue = dev_ingress_queue(dev);
1454 if (dev_queue &&
1455 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1456 &q_idx, s_q_idx) < 0)
1457 goto done;
1458
1459cont:
1460 idx++;
1461 }
1462
1463done:
1464 cb->args[0] = idx;
1465 cb->args[1] = q_idx;
1466
1467 return skb->len;
1468}
1469
1470
1471
1472/************************************************
1473 * Traffic classes manipulation. *
1474 ************************************************/
1475
1476
1477
1478static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n)
1479{
1480 struct net *net = sock_net(skb->sk);
1481 struct tcmsg *tcm = nlmsg_data(n);
1482 struct nlattr *tca[TCA_MAX + 1];
1483 struct net_device *dev;
1484 struct Qdisc *q = NULL;
1485 const struct Qdisc_class_ops *cops;
1486 unsigned long cl = 0;
1487 unsigned long new_cl;
1488 u32 portid;
1489 u32 clid;
1490 u32 qid;
1491 int err;
1492
1493 if ((n->nlmsg_type != RTM_GETTCLASS) && !netlink_capable(skb, CAP_NET_ADMIN))
1494 return -EPERM;
1495
1496 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1497 if (err < 0)
1498 return err;
1499
1500 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1501 if (!dev)
1502 return -ENODEV;
1503
1504 /*
1505 parent == TC_H_UNSPEC - unspecified parent.
1506 parent == TC_H_ROOT - class is root, which has no parent.
1507 parent == X:0 - parent is root class.
1508 parent == X:Y - parent is a node in hierarchy.
1509 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
1510
1511 handle == 0:0 - generate handle from kernel pool.
1512 handle == 0:Y - class is X:Y, where X:0 is qdisc.
1513 handle == X:Y - clear.
1514 handle == X:0 - root class.
1515 */
1516
1517 /* Step 1. Determine qdisc handle X:0 */
1518
1519 portid = tcm->tcm_parent;
1520 clid = tcm->tcm_handle;
1521 qid = TC_H_MAJ(clid);
1522
1523 if (portid != TC_H_ROOT) {
1524 u32 qid1 = TC_H_MAJ(portid);
1525
1526 if (qid && qid1) {
1527 /* If both majors are known, they must be identical. */
1528 if (qid != qid1)
1529 return -EINVAL;
1530 } else if (qid1) {
1531 qid = qid1;
1532 } else if (qid == 0)
1533 qid = dev->qdisc->handle;
1534
1535 /* Now qid is genuine qdisc handle consistent
1536 * both with parent and child.
1537 *
1538 * TC_H_MAJ(portid) still may be unspecified, complete it now.
1539 */
1540 if (portid)
1541 portid = TC_H_MAKE(qid, portid);
1542 } else {
1543 if (qid == 0)
1544 qid = dev->qdisc->handle;
1545 }
1546
1547 /* OK. Locate qdisc */
1548 q = qdisc_lookup(dev, qid);
1549 if (!q)
1550 return -ENOENT;
1551
1552 /* An check that it supports classes */
1553 cops = q->ops->cl_ops;
1554 if (cops == NULL)
1555 return -EINVAL;
1556
1557 /* Now try to get class */
1558 if (clid == 0) {
1559 if (portid == TC_H_ROOT)
1560 clid = qid;
1561 } else
1562 clid = TC_H_MAKE(qid, clid);
1563
1564 if (clid)
1565 cl = cops->get(q, clid);
1566
1567 if (cl == 0) {
1568 err = -ENOENT;
1569 if (n->nlmsg_type != RTM_NEWTCLASS ||
1570 !(n->nlmsg_flags & NLM_F_CREATE))
1571 goto out;
1572 } else {
1573 switch (n->nlmsg_type) {
1574 case RTM_NEWTCLASS:
1575 err = -EEXIST;
1576 if (n->nlmsg_flags & NLM_F_EXCL)
1577 goto out;
1578 break;
1579 case RTM_DELTCLASS:
1580 err = -EOPNOTSUPP;
1581 if (cops->delete)
1582 err = cops->delete(q, cl);
1583 if (err == 0)
1584 tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS);
1585 goto out;
1586 case RTM_GETTCLASS:
1587 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
1588 goto out;
1589 default:
1590 err = -EINVAL;
1591 goto out;
1592 }
1593 }
1594
1595 new_cl = cl;
1596 err = -EOPNOTSUPP;
1597 if (cops->change)
1598 err = cops->change(q, clid, portid, tca, &new_cl);
1599 if (err == 0)
1600 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
1601
1602out:
1603 if (cl)
1604 cops->put(q, cl);
1605
1606 return err;
1607}
1608
1609
1610static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1611 unsigned long cl,
1612 u32 portid, u32 seq, u16 flags, int event)
1613{
1614 struct tcmsg *tcm;
1615 struct nlmsghdr *nlh;
1616 unsigned char *b = skb_tail_pointer(skb);
1617 struct gnet_dump d;
1618 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1619
1620 cond_resched();
1621 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1622 if (!nlh)
1623 goto out_nlmsg_trim;
1624 tcm = nlmsg_data(nlh);
1625 tcm->tcm_family = AF_UNSPEC;
1626 tcm->tcm__pad1 = 0;
1627 tcm->tcm__pad2 = 0;
1628 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1629 tcm->tcm_parent = q->handle;
1630 tcm->tcm_handle = q->handle;
1631 tcm->tcm_info = 0;
1632 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1633 goto nla_put_failure;
1634 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1635 goto nla_put_failure;
1636
1637 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1638 qdisc_root_sleeping_lock(q), &d) < 0)
1639 goto nla_put_failure;
1640
1641 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1642 goto nla_put_failure;
1643
1644 if (gnet_stats_finish_copy(&d) < 0)
1645 goto nla_put_failure;
1646
1647 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1648 return skb->len;
1649
1650out_nlmsg_trim:
1651nla_put_failure:
1652 nlmsg_trim(skb, b);
1653 return -1;
1654}
1655
1656static int tclass_notify(struct net *net, struct sk_buff *oskb,
1657 struct nlmsghdr *n, struct Qdisc *q,
1658 unsigned long cl, int event)
1659{
1660 struct sk_buff *skb;
1661 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1662
1663 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1664 if (!skb)
1665 return -ENOBUFS;
1666
1667 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
1668 kfree_skb(skb);
1669 return -EINVAL;
1670 }
1671
1672 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1673 n->nlmsg_flags & NLM_F_ECHO);
1674}
1675
1676struct qdisc_dump_args {
1677 struct qdisc_walker w;
1678 struct sk_buff *skb;
1679 struct netlink_callback *cb;
1680};
1681
1682static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
1683{
1684 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
1685
1686 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
1687 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
1688}
1689
1690static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
1691 struct tcmsg *tcm, struct netlink_callback *cb,
1692 int *t_p, int s_t)
1693{
1694 struct qdisc_dump_args arg;
1695
1696 if (tc_qdisc_dump_ignore(q) ||
1697 *t_p < s_t || !q->ops->cl_ops ||
1698 (tcm->tcm_parent &&
1699 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
1700 (*t_p)++;
1701 return 0;
1702 }
1703 if (*t_p > s_t)
1704 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
1705 arg.w.fn = qdisc_class_dump;
1706 arg.skb = skb;
1707 arg.cb = cb;
1708 arg.w.stop = 0;
1709 arg.w.skip = cb->args[1];
1710 arg.w.count = 0;
1711 q->ops->cl_ops->walk(q, &arg.w);
1712 cb->args[1] = arg.w.count;
1713 if (arg.w.stop)
1714 return -1;
1715 (*t_p)++;
1716 return 0;
1717}
1718
1719static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
1720 struct tcmsg *tcm, struct netlink_callback *cb,
1721 int *t_p, int s_t)
1722{
1723 struct Qdisc *q;
1724
1725 if (!root)
1726 return 0;
1727
1728 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
1729 return -1;
1730
1731 list_for_each_entry(q, &root->list, list) {
1732 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
1733 return -1;
1734 }
1735
1736 return 0;
1737}
1738
1739static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
1740{
1741 struct tcmsg *tcm = nlmsg_data(cb->nlh);
1742 struct net *net = sock_net(skb->sk);
1743 struct netdev_queue *dev_queue;
1744 struct net_device *dev;
1745 int t, s_t;
1746
1747 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
1748 return 0;
1749 dev = dev_get_by_index(net, tcm->tcm_ifindex);
1750 if (!dev)
1751 return 0;
1752
1753 s_t = cb->args[0];
1754 t = 0;
1755
1756 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1757 goto done;
1758
1759 dev_queue = dev_ingress_queue(dev);
1760 if (dev_queue &&
1761 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
1762 &t, s_t) < 0)
1763 goto done;
1764
1765done:
1766 cb->args[0] = t;
1767
1768 dev_put(dev);
1769 return skb->len;
1770}
1771
1772/* Main classifier routine: scans classifier chain attached
1773 * to this qdisc, (optionally) tests for protocol and asks
1774 * specific classifiers.
1775 */
1776int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp,
1777 struct tcf_result *res)
1778{
1779 __be16 protocol = skb->protocol;
1780 int err;
1781
1782 for (; tp; tp = tp->next) {
1783 if (tp->protocol != protocol &&
1784 tp->protocol != htons(ETH_P_ALL))
1785 continue;
1786 err = tp->classify(skb, tp, res);
1787
1788 if (err >= 0) {
1789#ifdef CONFIG_NET_CLS_ACT
1790 if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
1791 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
1792#endif
1793 return err;
1794 }
1795 }
1796 return -1;
1797}
1798EXPORT_SYMBOL(tc_classify_compat);
1799
1800int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1801 struct tcf_result *res)
1802{
1803 int err = 0;
1804#ifdef CONFIG_NET_CLS_ACT
1805 const struct tcf_proto *otp = tp;
1806reclassify:
1807#endif
1808
1809 err = tc_classify_compat(skb, tp, res);
1810#ifdef CONFIG_NET_CLS_ACT
1811 if (err == TC_ACT_RECLASSIFY) {
1812 u32 verd = G_TC_VERD(skb->tc_verd);
1813 tp = otp;
1814
1815 if (verd++ >= MAX_REC_LOOP) {
1816 net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n",
1817 tp->q->ops->id,
1818 tp->prio & 0xffff,
1819 ntohs(tp->protocol));
1820 return TC_ACT_SHOT;
1821 }
1822 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
1823 goto reclassify;
1824 }
1825#endif
1826 return err;
1827}
1828EXPORT_SYMBOL(tc_classify);
1829
1830void tcf_destroy(struct tcf_proto *tp)
1831{
1832 tp->ops->destroy(tp);
1833 module_put(tp->ops->owner);
1834 kfree(tp);
1835}
1836
1837void tcf_destroy_chain(struct tcf_proto **fl)
1838{
1839 struct tcf_proto *tp;
1840
1841 while ((tp = *fl) != NULL) {
1842 *fl = tp->next;
1843 tcf_destroy(tp);
1844 }
1845}
1846EXPORT_SYMBOL(tcf_destroy_chain);
1847
1848#ifdef CONFIG_PROC_FS
1849static int psched_show(struct seq_file *seq, void *v)
1850{
1851 struct timespec ts;
1852
1853 hrtimer_get_res(CLOCK_MONOTONIC, &ts);
1854 seq_printf(seq, "%08x %08x %08x %08x\n",
1855 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1856 1000000,
1857 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
1858
1859 return 0;
1860}
1861
1862static int psched_open(struct inode *inode, struct file *file)
1863{
1864 return single_open(file, psched_show, NULL);
1865}
1866
1867static const struct file_operations psched_fops = {
1868 .owner = THIS_MODULE,
1869 .open = psched_open,
1870 .read = seq_read,
1871 .llseek = seq_lseek,
1872 .release = single_release,
1873};
1874
1875static int __net_init psched_net_init(struct net *net)
1876{
1877 struct proc_dir_entry *e;
1878
1879 e = proc_create("psched", 0, net->proc_net, &psched_fops);
1880 if (e == NULL)
1881 return -ENOMEM;
1882
1883 return 0;
1884}
1885
1886static void __net_exit psched_net_exit(struct net *net)
1887{
1888 remove_proc_entry("psched", net->proc_net);
1889}
1890#else
1891static int __net_init psched_net_init(struct net *net)
1892{
1893 return 0;
1894}
1895
1896static void __net_exit psched_net_exit(struct net *net)
1897{
1898}
1899#endif
1900
1901static struct pernet_operations psched_net_ops = {
1902 .init = psched_net_init,
1903 .exit = psched_net_exit,
1904};
1905
1906static int __init pktsched_init(void)
1907{
1908 int err;
1909
1910 err = register_pernet_subsys(&psched_net_ops);
1911 if (err) {
1912 pr_err("pktsched_init: "
1913 "cannot initialize per netns operations\n");
1914 return err;
1915 }
1916
1917 register_qdisc(&pfifo_fast_ops);
1918 register_qdisc(&pfifo_qdisc_ops);
1919 register_qdisc(&bfifo_qdisc_ops);
1920 register_qdisc(&pfifo_head_drop_qdisc_ops);
1921 register_qdisc(&mq_qdisc_ops);
1922
1923 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL);
1924 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL);
1925 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, NULL);
1926 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL);
1927 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL);
1928 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, NULL);
1929
1930 return 0;
1931}
1932
1933subsys_initcall(pktsched_init);