Loading...
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);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/sch_api.c Packet scheduler API.
4 *
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 *
7 * Fixes:
8 *
9 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
10 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
11 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
12 */
13
14#include <linux/module.h>
15#include <linux/types.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/skbuff.h>
20#include <linux/init.h>
21#include <linux/proc_fs.h>
22#include <linux/seq_file.h>
23#include <linux/kmod.h>
24#include <linux/list.h>
25#include <linux/hrtimer.h>
26#include <linux/slab.h>
27#include <linux/hashtable.h>
28
29#include <net/net_namespace.h>
30#include <net/sock.h>
31#include <net/netlink.h>
32#include <net/pkt_sched.h>
33#include <net/pkt_cls.h>
34#include <net/tc_wrapper.h>
35
36#include <trace/events/qdisc.h>
37
38/*
39
40 Short review.
41 -------------
42
43 This file consists of two interrelated parts:
44
45 1. queueing disciplines manager frontend.
46 2. traffic classes manager frontend.
47
48 Generally, queueing discipline ("qdisc") is a black box,
49 which is able to enqueue packets and to dequeue them (when
50 device is ready to send something) in order and at times
51 determined by algorithm hidden in it.
52
53 qdisc's are divided to two categories:
54 - "queues", which have no internal structure visible from outside.
55 - "schedulers", which split all the packets to "traffic classes",
56 using "packet classifiers" (look at cls_api.c)
57
58 In turn, classes may have child qdiscs (as rule, queues)
59 attached to them etc. etc. etc.
60
61 The goal of the routines in this file is to translate
62 information supplied by user in the form of handles
63 to more intelligible for kernel form, to make some sanity
64 checks and part of work, which is common to all qdiscs
65 and to provide rtnetlink notifications.
66
67 All real intelligent work is done inside qdisc modules.
68
69
70
71 Every discipline has two major routines: enqueue and dequeue.
72
73 ---dequeue
74
75 dequeue usually returns a skb to send. It is allowed to return NULL,
76 but it does not mean that queue is empty, it just means that
77 discipline does not want to send anything this time.
78 Queue is really empty if q->q.qlen == 0.
79 For complicated disciplines with multiple queues q->q is not
80 real packet queue, but however q->q.qlen must be valid.
81
82 ---enqueue
83
84 enqueue returns 0, if packet was enqueued successfully.
85 If packet (this one or another one) was dropped, it returns
86 not zero error code.
87 NET_XMIT_DROP - this packet dropped
88 Expected action: do not backoff, but wait until queue will clear.
89 NET_XMIT_CN - probably this packet enqueued, but another one dropped.
90 Expected action: backoff or ignore
91
92 Auxiliary routines:
93
94 ---peek
95
96 like dequeue but without removing a packet from the queue
97
98 ---reset
99
100 returns qdisc to initial state: purge all buffers, clear all
101 timers, counters (except for statistics) etc.
102
103 ---init
104
105 initializes newly created qdisc.
106
107 ---destroy
108
109 destroys resources allocated by init and during lifetime of qdisc.
110
111 ---change
112
113 changes qdisc parameters.
114 */
115
116/* Protects list of registered TC modules. It is pure SMP lock. */
117static DEFINE_RWLOCK(qdisc_mod_lock);
118
119
120/************************************************
121 * Queueing disciplines manipulation. *
122 ************************************************/
123
124
125/* The list of all installed queueing disciplines. */
126
127static struct Qdisc_ops *qdisc_base;
128
129/* Register/unregister queueing discipline */
130
131int register_qdisc(struct Qdisc_ops *qops)
132{
133 struct Qdisc_ops *q, **qp;
134 int rc = -EEXIST;
135
136 write_lock(&qdisc_mod_lock);
137 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
138 if (!strcmp(qops->id, q->id))
139 goto out;
140
141 if (qops->enqueue == NULL)
142 qops->enqueue = noop_qdisc_ops.enqueue;
143 if (qops->peek == NULL) {
144 if (qops->dequeue == NULL)
145 qops->peek = noop_qdisc_ops.peek;
146 else
147 goto out_einval;
148 }
149 if (qops->dequeue == NULL)
150 qops->dequeue = noop_qdisc_ops.dequeue;
151
152 if (qops->cl_ops) {
153 const struct Qdisc_class_ops *cops = qops->cl_ops;
154
155 if (!(cops->find && cops->walk && cops->leaf))
156 goto out_einval;
157
158 if (cops->tcf_block && !(cops->bind_tcf && cops->unbind_tcf))
159 goto out_einval;
160 }
161
162 qops->next = NULL;
163 *qp = qops;
164 rc = 0;
165out:
166 write_unlock(&qdisc_mod_lock);
167 return rc;
168
169out_einval:
170 rc = -EINVAL;
171 goto out;
172}
173EXPORT_SYMBOL(register_qdisc);
174
175void unregister_qdisc(struct Qdisc_ops *qops)
176{
177 struct Qdisc_ops *q, **qp;
178 int err = -ENOENT;
179
180 write_lock(&qdisc_mod_lock);
181 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
182 if (q == qops)
183 break;
184 if (q) {
185 *qp = q->next;
186 q->next = NULL;
187 err = 0;
188 }
189 write_unlock(&qdisc_mod_lock);
190
191 WARN(err, "unregister qdisc(%s) failed\n", qops->id);
192}
193EXPORT_SYMBOL(unregister_qdisc);
194
195/* Get default qdisc if not otherwise specified */
196void qdisc_get_default(char *name, size_t len)
197{
198 read_lock(&qdisc_mod_lock);
199 strscpy(name, default_qdisc_ops->id, len);
200 read_unlock(&qdisc_mod_lock);
201}
202
203static struct Qdisc_ops *qdisc_lookup_default(const char *name)
204{
205 struct Qdisc_ops *q = NULL;
206
207 for (q = qdisc_base; q; q = q->next) {
208 if (!strcmp(name, q->id)) {
209 if (!try_module_get(q->owner))
210 q = NULL;
211 break;
212 }
213 }
214
215 return q;
216}
217
218/* Set new default qdisc to use */
219int qdisc_set_default(const char *name)
220{
221 const struct Qdisc_ops *ops;
222
223 if (!capable(CAP_NET_ADMIN))
224 return -EPERM;
225
226 write_lock(&qdisc_mod_lock);
227 ops = qdisc_lookup_default(name);
228 if (!ops) {
229 /* Not found, drop lock and try to load module */
230 write_unlock(&qdisc_mod_lock);
231 request_module("sch_%s", name);
232 write_lock(&qdisc_mod_lock);
233
234 ops = qdisc_lookup_default(name);
235 }
236
237 if (ops) {
238 /* Set new default */
239 module_put(default_qdisc_ops->owner);
240 default_qdisc_ops = ops;
241 }
242 write_unlock(&qdisc_mod_lock);
243
244 return ops ? 0 : -ENOENT;
245}
246
247#ifdef CONFIG_NET_SCH_DEFAULT
248/* Set default value from kernel config */
249static int __init sch_default_qdisc(void)
250{
251 return qdisc_set_default(CONFIG_DEFAULT_NET_SCH);
252}
253late_initcall(sch_default_qdisc);
254#endif
255
256/* We know handle. Find qdisc among all qdisc's attached to device
257 * (root qdisc, all its children, children of children etc.)
258 * Note: caller either uses rtnl or rcu_read_lock()
259 */
260
261static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
262{
263 struct Qdisc *q;
264
265 if (!qdisc_dev(root))
266 return (root->handle == handle ? root : NULL);
267
268 if (!(root->flags & TCQ_F_BUILTIN) &&
269 root->handle == handle)
270 return root;
271
272 hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle,
273 lockdep_rtnl_is_held()) {
274 if (q->handle == handle)
275 return q;
276 }
277 return NULL;
278}
279
280void qdisc_hash_add(struct Qdisc *q, bool invisible)
281{
282 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
283 ASSERT_RTNL();
284 hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle);
285 if (invisible)
286 q->flags |= TCQ_F_INVISIBLE;
287 }
288}
289EXPORT_SYMBOL(qdisc_hash_add);
290
291void qdisc_hash_del(struct Qdisc *q)
292{
293 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
294 ASSERT_RTNL();
295 hash_del_rcu(&q->hash);
296 }
297}
298EXPORT_SYMBOL(qdisc_hash_del);
299
300struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
301{
302 struct Qdisc *q;
303
304 if (!handle)
305 return NULL;
306 q = qdisc_match_from_root(rtnl_dereference(dev->qdisc), handle);
307 if (q)
308 goto out;
309
310 if (dev_ingress_queue(dev))
311 q = qdisc_match_from_root(
312 rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping),
313 handle);
314out:
315 return q;
316}
317
318struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle)
319{
320 struct netdev_queue *nq;
321 struct Qdisc *q;
322
323 if (!handle)
324 return NULL;
325 q = qdisc_match_from_root(rcu_dereference(dev->qdisc), handle);
326 if (q)
327 goto out;
328
329 nq = dev_ingress_queue_rcu(dev);
330 if (nq)
331 q = qdisc_match_from_root(rcu_dereference(nq->qdisc_sleeping),
332 handle);
333out:
334 return q;
335}
336
337static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
338{
339 unsigned long cl;
340 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
341
342 if (cops == NULL)
343 return NULL;
344 cl = cops->find(p, classid);
345
346 if (cl == 0)
347 return NULL;
348 return cops->leaf(p, cl);
349}
350
351/* Find queueing discipline by name */
352
353static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
354{
355 struct Qdisc_ops *q = NULL;
356
357 if (kind) {
358 read_lock(&qdisc_mod_lock);
359 for (q = qdisc_base; q; q = q->next) {
360 if (nla_strcmp(kind, q->id) == 0) {
361 if (!try_module_get(q->owner))
362 q = NULL;
363 break;
364 }
365 }
366 read_unlock(&qdisc_mod_lock);
367 }
368 return q;
369}
370
371/* The linklayer setting were not transferred from iproute2, in older
372 * versions, and the rate tables lookup systems have been dropped in
373 * the kernel. To keep backward compatible with older iproute2 tc
374 * utils, we detect the linklayer setting by detecting if the rate
375 * table were modified.
376 *
377 * For linklayer ATM table entries, the rate table will be aligned to
378 * 48 bytes, thus some table entries will contain the same value. The
379 * mpu (min packet unit) is also encoded into the old rate table, thus
380 * starting from the mpu, we find low and high table entries for
381 * mapping this cell. If these entries contain the same value, when
382 * the rate tables have been modified for linklayer ATM.
383 *
384 * This is done by rounding mpu to the nearest 48 bytes cell/entry,
385 * and then roundup to the next cell, calc the table entry one below,
386 * and compare.
387 */
388static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab)
389{
390 int low = roundup(r->mpu, 48);
391 int high = roundup(low+1, 48);
392 int cell_low = low >> r->cell_log;
393 int cell_high = (high >> r->cell_log) - 1;
394
395 /* rtab is too inaccurate at rates > 100Mbit/s */
396 if ((r->rate > (100000000/8)) || (rtab[0] == 0)) {
397 pr_debug("TC linklayer: Giving up ATM detection\n");
398 return TC_LINKLAYER_ETHERNET;
399 }
400
401 if ((cell_high > cell_low) && (cell_high < 256)
402 && (rtab[cell_low] == rtab[cell_high])) {
403 pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n",
404 cell_low, cell_high, rtab[cell_high]);
405 return TC_LINKLAYER_ATM;
406 }
407 return TC_LINKLAYER_ETHERNET;
408}
409
410static struct qdisc_rate_table *qdisc_rtab_list;
411
412struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
413 struct nlattr *tab,
414 struct netlink_ext_ack *extack)
415{
416 struct qdisc_rate_table *rtab;
417
418 if (tab == NULL || r->rate == 0 ||
419 r->cell_log == 0 || r->cell_log >= 32 ||
420 nla_len(tab) != TC_RTAB_SIZE) {
421 NL_SET_ERR_MSG(extack, "Invalid rate table parameters for searching");
422 return NULL;
423 }
424
425 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
426 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
427 !memcmp(&rtab->data, nla_data(tab), 1024)) {
428 rtab->refcnt++;
429 return rtab;
430 }
431 }
432
433 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
434 if (rtab) {
435 rtab->rate = *r;
436 rtab->refcnt = 1;
437 memcpy(rtab->data, nla_data(tab), 1024);
438 if (r->linklayer == TC_LINKLAYER_UNAWARE)
439 r->linklayer = __detect_linklayer(r, rtab->data);
440 rtab->next = qdisc_rtab_list;
441 qdisc_rtab_list = rtab;
442 } else {
443 NL_SET_ERR_MSG(extack, "Failed to allocate new qdisc rate table");
444 }
445 return rtab;
446}
447EXPORT_SYMBOL(qdisc_get_rtab);
448
449void qdisc_put_rtab(struct qdisc_rate_table *tab)
450{
451 struct qdisc_rate_table *rtab, **rtabp;
452
453 if (!tab || --tab->refcnt)
454 return;
455
456 for (rtabp = &qdisc_rtab_list;
457 (rtab = *rtabp) != NULL;
458 rtabp = &rtab->next) {
459 if (rtab == tab) {
460 *rtabp = rtab->next;
461 kfree(rtab);
462 return;
463 }
464 }
465}
466EXPORT_SYMBOL(qdisc_put_rtab);
467
468static LIST_HEAD(qdisc_stab_list);
469
470static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
471 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) },
472 [TCA_STAB_DATA] = { .type = NLA_BINARY },
473};
474
475static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt,
476 struct netlink_ext_ack *extack)
477{
478 struct nlattr *tb[TCA_STAB_MAX + 1];
479 struct qdisc_size_table *stab;
480 struct tc_sizespec *s;
481 unsigned int tsize = 0;
482 u16 *tab = NULL;
483 int err;
484
485 err = nla_parse_nested_deprecated(tb, TCA_STAB_MAX, opt, stab_policy,
486 extack);
487 if (err < 0)
488 return ERR_PTR(err);
489 if (!tb[TCA_STAB_BASE]) {
490 NL_SET_ERR_MSG(extack, "Size table base attribute is missing");
491 return ERR_PTR(-EINVAL);
492 }
493
494 s = nla_data(tb[TCA_STAB_BASE]);
495
496 if (s->tsize > 0) {
497 if (!tb[TCA_STAB_DATA]) {
498 NL_SET_ERR_MSG(extack, "Size table data attribute is missing");
499 return ERR_PTR(-EINVAL);
500 }
501 tab = nla_data(tb[TCA_STAB_DATA]);
502 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
503 }
504
505 if (tsize != s->tsize || (!tab && tsize > 0)) {
506 NL_SET_ERR_MSG(extack, "Invalid size of size table");
507 return ERR_PTR(-EINVAL);
508 }
509
510 list_for_each_entry(stab, &qdisc_stab_list, list) {
511 if (memcmp(&stab->szopts, s, sizeof(*s)))
512 continue;
513 if (tsize > 0 &&
514 memcmp(stab->data, tab, flex_array_size(stab, data, tsize)))
515 continue;
516 stab->refcnt++;
517 return stab;
518 }
519
520 if (s->size_log > STAB_SIZE_LOG_MAX ||
521 s->cell_log > STAB_SIZE_LOG_MAX) {
522 NL_SET_ERR_MSG(extack, "Invalid logarithmic size of size table");
523 return ERR_PTR(-EINVAL);
524 }
525
526 stab = kmalloc(struct_size(stab, data, tsize), GFP_KERNEL);
527 if (!stab)
528 return ERR_PTR(-ENOMEM);
529
530 stab->refcnt = 1;
531 stab->szopts = *s;
532 if (tsize > 0)
533 memcpy(stab->data, tab, flex_array_size(stab, data, tsize));
534
535 list_add_tail(&stab->list, &qdisc_stab_list);
536
537 return stab;
538}
539
540void qdisc_put_stab(struct qdisc_size_table *tab)
541{
542 if (!tab)
543 return;
544
545 if (--tab->refcnt == 0) {
546 list_del(&tab->list);
547 kfree_rcu(tab, rcu);
548 }
549}
550EXPORT_SYMBOL(qdisc_put_stab);
551
552static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
553{
554 struct nlattr *nest;
555
556 nest = nla_nest_start_noflag(skb, TCA_STAB);
557 if (nest == NULL)
558 goto nla_put_failure;
559 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
560 goto nla_put_failure;
561 nla_nest_end(skb, nest);
562
563 return skb->len;
564
565nla_put_failure:
566 return -1;
567}
568
569void __qdisc_calculate_pkt_len(struct sk_buff *skb,
570 const struct qdisc_size_table *stab)
571{
572 int pkt_len, slot;
573
574 pkt_len = skb->len + stab->szopts.overhead;
575 if (unlikely(!stab->szopts.tsize))
576 goto out;
577
578 slot = pkt_len + stab->szopts.cell_align;
579 if (unlikely(slot < 0))
580 slot = 0;
581
582 slot >>= stab->szopts.cell_log;
583 if (likely(slot < stab->szopts.tsize))
584 pkt_len = stab->data[slot];
585 else
586 pkt_len = stab->data[stab->szopts.tsize - 1] *
587 (slot / stab->szopts.tsize) +
588 stab->data[slot % stab->szopts.tsize];
589
590 pkt_len <<= stab->szopts.size_log;
591out:
592 if (unlikely(pkt_len < 1))
593 pkt_len = 1;
594 qdisc_skb_cb(skb)->pkt_len = pkt_len;
595}
596EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
597
598void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc)
599{
600 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
601 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
602 txt, qdisc->ops->id, qdisc->handle >> 16);
603 qdisc->flags |= TCQ_F_WARN_NONWC;
604 }
605}
606EXPORT_SYMBOL(qdisc_warn_nonwc);
607
608static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
609{
610 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
611 timer);
612
613 rcu_read_lock();
614 __netif_schedule(qdisc_root(wd->qdisc));
615 rcu_read_unlock();
616
617 return HRTIMER_NORESTART;
618}
619
620void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
621 clockid_t clockid)
622{
623 hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED);
624 wd->timer.function = qdisc_watchdog;
625 wd->qdisc = qdisc;
626}
627EXPORT_SYMBOL(qdisc_watchdog_init_clockid);
628
629void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
630{
631 qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC);
632}
633EXPORT_SYMBOL(qdisc_watchdog_init);
634
635void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
636 u64 delta_ns)
637{
638 bool deactivated;
639
640 rcu_read_lock();
641 deactivated = test_bit(__QDISC_STATE_DEACTIVATED,
642 &qdisc_root_sleeping(wd->qdisc)->state);
643 rcu_read_unlock();
644 if (deactivated)
645 return;
646
647 if (hrtimer_is_queued(&wd->timer)) {
648 u64 softexpires;
649
650 softexpires = ktime_to_ns(hrtimer_get_softexpires(&wd->timer));
651 /* If timer is already set in [expires, expires + delta_ns],
652 * do not reprogram it.
653 */
654 if (softexpires - expires <= delta_ns)
655 return;
656 }
657
658 hrtimer_start_range_ns(&wd->timer,
659 ns_to_ktime(expires),
660 delta_ns,
661 HRTIMER_MODE_ABS_PINNED);
662}
663EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns);
664
665void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
666{
667 hrtimer_cancel(&wd->timer);
668}
669EXPORT_SYMBOL(qdisc_watchdog_cancel);
670
671static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
672{
673 struct hlist_head *h;
674 unsigned int i;
675
676 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL);
677
678 if (h != NULL) {
679 for (i = 0; i < n; i++)
680 INIT_HLIST_HEAD(&h[i]);
681 }
682 return h;
683}
684
685void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
686{
687 struct Qdisc_class_common *cl;
688 struct hlist_node *next;
689 struct hlist_head *nhash, *ohash;
690 unsigned int nsize, nmask, osize;
691 unsigned int i, h;
692
693 /* Rehash when load factor exceeds 0.75 */
694 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
695 return;
696 nsize = clhash->hashsize * 2;
697 nmask = nsize - 1;
698 nhash = qdisc_class_hash_alloc(nsize);
699 if (nhash == NULL)
700 return;
701
702 ohash = clhash->hash;
703 osize = clhash->hashsize;
704
705 sch_tree_lock(sch);
706 for (i = 0; i < osize; i++) {
707 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
708 h = qdisc_class_hash(cl->classid, nmask);
709 hlist_add_head(&cl->hnode, &nhash[h]);
710 }
711 }
712 clhash->hash = nhash;
713 clhash->hashsize = nsize;
714 clhash->hashmask = nmask;
715 sch_tree_unlock(sch);
716
717 kvfree(ohash);
718}
719EXPORT_SYMBOL(qdisc_class_hash_grow);
720
721int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
722{
723 unsigned int size = 4;
724
725 clhash->hash = qdisc_class_hash_alloc(size);
726 if (!clhash->hash)
727 return -ENOMEM;
728 clhash->hashsize = size;
729 clhash->hashmask = size - 1;
730 clhash->hashelems = 0;
731 return 0;
732}
733EXPORT_SYMBOL(qdisc_class_hash_init);
734
735void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
736{
737 kvfree(clhash->hash);
738}
739EXPORT_SYMBOL(qdisc_class_hash_destroy);
740
741void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
742 struct Qdisc_class_common *cl)
743{
744 unsigned int h;
745
746 INIT_HLIST_NODE(&cl->hnode);
747 h = qdisc_class_hash(cl->classid, clhash->hashmask);
748 hlist_add_head(&cl->hnode, &clhash->hash[h]);
749 clhash->hashelems++;
750}
751EXPORT_SYMBOL(qdisc_class_hash_insert);
752
753void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
754 struct Qdisc_class_common *cl)
755{
756 hlist_del(&cl->hnode);
757 clhash->hashelems--;
758}
759EXPORT_SYMBOL(qdisc_class_hash_remove);
760
761/* Allocate an unique handle from space managed by kernel
762 * Possible range is [8000-FFFF]:0000 (0x8000 values)
763 */
764static u32 qdisc_alloc_handle(struct net_device *dev)
765{
766 int i = 0x8000;
767 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
768
769 do {
770 autohandle += TC_H_MAKE(0x10000U, 0);
771 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
772 autohandle = TC_H_MAKE(0x80000000U, 0);
773 if (!qdisc_lookup(dev, autohandle))
774 return autohandle;
775 cond_resched();
776 } while (--i > 0);
777
778 return 0;
779}
780
781void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len)
782{
783 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED;
784 const struct Qdisc_class_ops *cops;
785 unsigned long cl;
786 u32 parentid;
787 bool notify;
788 int drops;
789
790 if (n == 0 && len == 0)
791 return;
792 drops = max_t(int, n, 0);
793 rcu_read_lock();
794 while ((parentid = sch->parent)) {
795 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
796 break;
797
798 if (sch->flags & TCQ_F_NOPARENT)
799 break;
800 /* Notify parent qdisc only if child qdisc becomes empty.
801 *
802 * If child was empty even before update then backlog
803 * counter is screwed and we skip notification because
804 * parent class is already passive.
805 *
806 * If the original child was offloaded then it is allowed
807 * to be seem as empty, so the parent is notified anyway.
808 */
809 notify = !sch->q.qlen && !WARN_ON_ONCE(!n &&
810 !qdisc_is_offloaded);
811 /* TODO: perform the search on a per txq basis */
812 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
813 if (sch == NULL) {
814 WARN_ON_ONCE(parentid != TC_H_ROOT);
815 break;
816 }
817 cops = sch->ops->cl_ops;
818 if (notify && cops->qlen_notify) {
819 cl = cops->find(sch, parentid);
820 cops->qlen_notify(sch, cl);
821 }
822 sch->q.qlen -= n;
823 sch->qstats.backlog -= len;
824 __qdisc_qstats_drop(sch, drops);
825 }
826 rcu_read_unlock();
827}
828EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
829
830int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type,
831 void *type_data)
832{
833 struct net_device *dev = qdisc_dev(sch);
834 int err;
835
836 sch->flags &= ~TCQ_F_OFFLOADED;
837 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
838 return 0;
839
840 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
841 if (err == -EOPNOTSUPP)
842 return 0;
843
844 if (!err)
845 sch->flags |= TCQ_F_OFFLOADED;
846
847 return err;
848}
849EXPORT_SYMBOL(qdisc_offload_dump_helper);
850
851void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
852 struct Qdisc *new, struct Qdisc *old,
853 enum tc_setup_type type, void *type_data,
854 struct netlink_ext_ack *extack)
855{
856 bool any_qdisc_is_offloaded;
857 int err;
858
859 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
860 return;
861
862 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
863
864 /* Don't report error if the graft is part of destroy operation. */
865 if (!err || !new || new == &noop_qdisc)
866 return;
867
868 /* Don't report error if the parent, the old child and the new
869 * one are not offloaded.
870 */
871 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED;
872 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED;
873 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED;
874
875 if (any_qdisc_is_offloaded)
876 NL_SET_ERR_MSG(extack, "Offloading graft operation failed.");
877}
878EXPORT_SYMBOL(qdisc_offload_graft_helper);
879
880void qdisc_offload_query_caps(struct net_device *dev,
881 enum tc_setup_type type,
882 void *caps, size_t caps_len)
883{
884 const struct net_device_ops *ops = dev->netdev_ops;
885 struct tc_query_caps_base base = {
886 .type = type,
887 .caps = caps,
888 };
889
890 memset(caps, 0, caps_len);
891
892 if (ops->ndo_setup_tc)
893 ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base);
894}
895EXPORT_SYMBOL(qdisc_offload_query_caps);
896
897static void qdisc_offload_graft_root(struct net_device *dev,
898 struct Qdisc *new, struct Qdisc *old,
899 struct netlink_ext_ack *extack)
900{
901 struct tc_root_qopt_offload graft_offload = {
902 .command = TC_ROOT_GRAFT,
903 .handle = new ? new->handle : 0,
904 .ingress = (new && new->flags & TCQ_F_INGRESS) ||
905 (old && old->flags & TCQ_F_INGRESS),
906 };
907
908 qdisc_offload_graft_helper(dev, NULL, new, old,
909 TC_SETUP_ROOT_QDISC, &graft_offload, extack);
910}
911
912static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
913 u32 portid, u32 seq, u16 flags, int event,
914 struct netlink_ext_ack *extack)
915{
916 struct gnet_stats_basic_sync __percpu *cpu_bstats = NULL;
917 struct gnet_stats_queue __percpu *cpu_qstats = NULL;
918 struct tcmsg *tcm;
919 struct nlmsghdr *nlh;
920 unsigned char *b = skb_tail_pointer(skb);
921 struct gnet_dump d;
922 struct qdisc_size_table *stab;
923 u32 block_index;
924 __u32 qlen;
925
926 cond_resched();
927 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
928 if (!nlh)
929 goto out_nlmsg_trim;
930 tcm = nlmsg_data(nlh);
931 tcm->tcm_family = AF_UNSPEC;
932 tcm->tcm__pad1 = 0;
933 tcm->tcm__pad2 = 0;
934 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
935 tcm->tcm_parent = clid;
936 tcm->tcm_handle = q->handle;
937 tcm->tcm_info = refcount_read(&q->refcnt);
938 if (nla_put_string(skb, TCA_KIND, q->ops->id))
939 goto nla_put_failure;
940 if (q->ops->ingress_block_get) {
941 block_index = q->ops->ingress_block_get(q);
942 if (block_index &&
943 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index))
944 goto nla_put_failure;
945 }
946 if (q->ops->egress_block_get) {
947 block_index = q->ops->egress_block_get(q);
948 if (block_index &&
949 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index))
950 goto nla_put_failure;
951 }
952 if (q->ops->dump && q->ops->dump(q, skb) < 0)
953 goto nla_put_failure;
954 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED)))
955 goto nla_put_failure;
956 qlen = qdisc_qlen_sum(q);
957
958 stab = rtnl_dereference(q->stab);
959 if (stab && qdisc_dump_stab(skb, stab) < 0)
960 goto nla_put_failure;
961
962 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
963 NULL, &d, TCA_PAD) < 0)
964 goto nla_put_failure;
965
966 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
967 goto nla_put_failure;
968
969 if (qdisc_is_percpu_stats(q)) {
970 cpu_bstats = q->cpu_bstats;
971 cpu_qstats = q->cpu_qstats;
972 }
973
974 if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats, true) < 0 ||
975 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
976 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
977 goto nla_put_failure;
978
979 if (gnet_stats_finish_copy(&d) < 0)
980 goto nla_put_failure;
981
982 if (extack && extack->_msg &&
983 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
984 goto out_nlmsg_trim;
985
986 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
987
988 return skb->len;
989
990out_nlmsg_trim:
991nla_put_failure:
992 nlmsg_trim(skb, b);
993 return -1;
994}
995
996static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible)
997{
998 if (q->flags & TCQ_F_BUILTIN)
999 return true;
1000 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
1001 return true;
1002
1003 return false;
1004}
1005
1006static int qdisc_get_notify(struct net *net, struct sk_buff *oskb,
1007 struct nlmsghdr *n, u32 clid, struct Qdisc *q,
1008 struct netlink_ext_ack *extack)
1009{
1010 struct sk_buff *skb;
1011 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1012
1013 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1014 if (!skb)
1015 return -ENOBUFS;
1016
1017 if (!tc_qdisc_dump_ignore(q, false)) {
1018 if (tc_fill_qdisc(skb, q, clid, portid, n->nlmsg_seq, 0,
1019 RTM_NEWQDISC, extack) < 0)
1020 goto err_out;
1021 }
1022
1023 if (skb->len)
1024 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1025 n->nlmsg_flags & NLM_F_ECHO);
1026
1027err_out:
1028 kfree_skb(skb);
1029 return -EINVAL;
1030}
1031
1032static int qdisc_notify(struct net *net, struct sk_buff *oskb,
1033 struct nlmsghdr *n, u32 clid,
1034 struct Qdisc *old, struct Qdisc *new,
1035 struct netlink_ext_ack *extack)
1036{
1037 struct sk_buff *skb;
1038 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1039
1040 if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
1041 return 0;
1042
1043 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1044 if (!skb)
1045 return -ENOBUFS;
1046
1047 if (old && !tc_qdisc_dump_ignore(old, false)) {
1048 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
1049 0, RTM_DELQDISC, extack) < 0)
1050 goto err_out;
1051 }
1052 if (new && !tc_qdisc_dump_ignore(new, false)) {
1053 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
1054 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC, extack) < 0)
1055 goto err_out;
1056 }
1057
1058 if (skb->len)
1059 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1060 n->nlmsg_flags & NLM_F_ECHO);
1061
1062err_out:
1063 kfree_skb(skb);
1064 return -EINVAL;
1065}
1066
1067static void notify_and_destroy(struct net *net, struct sk_buff *skb,
1068 struct nlmsghdr *n, u32 clid,
1069 struct Qdisc *old, struct Qdisc *new,
1070 struct netlink_ext_ack *extack)
1071{
1072 if (new || old)
1073 qdisc_notify(net, skb, n, clid, old, new, extack);
1074
1075 if (old)
1076 qdisc_put(old);
1077}
1078
1079static void qdisc_clear_nolock(struct Qdisc *sch)
1080{
1081 sch->flags &= ~TCQ_F_NOLOCK;
1082 if (!(sch->flags & TCQ_F_CPUSTATS))
1083 return;
1084
1085 free_percpu(sch->cpu_bstats);
1086 free_percpu(sch->cpu_qstats);
1087 sch->cpu_bstats = NULL;
1088 sch->cpu_qstats = NULL;
1089 sch->flags &= ~TCQ_F_CPUSTATS;
1090}
1091
1092/* Graft qdisc "new" to class "classid" of qdisc "parent" or
1093 * to device "dev".
1094 *
1095 * When appropriate send a netlink notification using 'skb'
1096 * and "n".
1097 *
1098 * On success, destroy old qdisc.
1099 */
1100
1101static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
1102 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
1103 struct Qdisc *new, struct Qdisc *old,
1104 struct netlink_ext_ack *extack)
1105{
1106 struct Qdisc *q = old;
1107 struct net *net = dev_net(dev);
1108
1109 if (parent == NULL) {
1110 unsigned int i, num_q, ingress;
1111 struct netdev_queue *dev_queue;
1112
1113 ingress = 0;
1114 num_q = dev->num_tx_queues;
1115 if ((q && q->flags & TCQ_F_INGRESS) ||
1116 (new && new->flags & TCQ_F_INGRESS)) {
1117 ingress = 1;
1118 dev_queue = dev_ingress_queue(dev);
1119 if (!dev_queue) {
1120 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue");
1121 return -ENOENT;
1122 }
1123
1124 q = rtnl_dereference(dev_queue->qdisc_sleeping);
1125
1126 /* This is the counterpart of that qdisc_refcount_inc_nz() call in
1127 * __tcf_qdisc_find() for filter requests.
1128 */
1129 if (!qdisc_refcount_dec_if_one(q)) {
1130 NL_SET_ERR_MSG(extack,
1131 "Current ingress or clsact Qdisc has ongoing filter requests");
1132 return -EBUSY;
1133 }
1134 }
1135
1136 if (dev->flags & IFF_UP)
1137 dev_deactivate(dev);
1138
1139 qdisc_offload_graft_root(dev, new, old, extack);
1140
1141 if (new && new->ops->attach && !ingress)
1142 goto skip;
1143
1144 if (!ingress) {
1145 for (i = 0; i < num_q; i++) {
1146 dev_queue = netdev_get_tx_queue(dev, i);
1147 old = dev_graft_qdisc(dev_queue, new);
1148
1149 if (new && i > 0)
1150 qdisc_refcount_inc(new);
1151 qdisc_put(old);
1152 }
1153 } else {
1154 old = dev_graft_qdisc(dev_queue, NULL);
1155
1156 /* {ingress,clsact}_destroy() @old before grafting @new to avoid
1157 * unprotected concurrent accesses to net_device::miniq_{in,e}gress
1158 * pointer(s) in mini_qdisc_pair_swap().
1159 */
1160 qdisc_notify(net, skb, n, classid, old, new, extack);
1161 qdisc_destroy(old);
1162
1163 dev_graft_qdisc(dev_queue, new);
1164 }
1165
1166skip:
1167 if (!ingress) {
1168 old = rtnl_dereference(dev->qdisc);
1169 if (new && !new->ops->attach)
1170 qdisc_refcount_inc(new);
1171 rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc);
1172
1173 notify_and_destroy(net, skb, n, classid, old, new, extack);
1174
1175 if (new && new->ops->attach)
1176 new->ops->attach(new);
1177 }
1178
1179 if (dev->flags & IFF_UP)
1180 dev_activate(dev);
1181 } else {
1182 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
1183 unsigned long cl;
1184 int err;
1185
1186 /* Only support running class lockless if parent is lockless */
1187 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK))
1188 qdisc_clear_nolock(new);
1189
1190 if (!cops || !cops->graft)
1191 return -EOPNOTSUPP;
1192
1193 cl = cops->find(parent, classid);
1194 if (!cl) {
1195 NL_SET_ERR_MSG(extack, "Specified class not found");
1196 return -ENOENT;
1197 }
1198
1199 if (new && new->ops == &noqueue_qdisc_ops) {
1200 NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class");
1201 return -EINVAL;
1202 }
1203
1204 err = cops->graft(parent, cl, new, &old, extack);
1205 if (err)
1206 return err;
1207 notify_and_destroy(net, skb, n, classid, old, new, extack);
1208 }
1209 return 0;
1210}
1211
1212static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca,
1213 struct netlink_ext_ack *extack)
1214{
1215 u32 block_index;
1216
1217 if (tca[TCA_INGRESS_BLOCK]) {
1218 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]);
1219
1220 if (!block_index) {
1221 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0");
1222 return -EINVAL;
1223 }
1224 if (!sch->ops->ingress_block_set) {
1225 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported");
1226 return -EOPNOTSUPP;
1227 }
1228 sch->ops->ingress_block_set(sch, block_index);
1229 }
1230 if (tca[TCA_EGRESS_BLOCK]) {
1231 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]);
1232
1233 if (!block_index) {
1234 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0");
1235 return -EINVAL;
1236 }
1237 if (!sch->ops->egress_block_set) {
1238 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported");
1239 return -EOPNOTSUPP;
1240 }
1241 sch->ops->egress_block_set(sch, block_index);
1242 }
1243 return 0;
1244}
1245
1246/*
1247 Allocate and initialize new qdisc.
1248
1249 Parameters are passed via opt.
1250 */
1251
1252static struct Qdisc *qdisc_create(struct net_device *dev,
1253 struct netdev_queue *dev_queue,
1254 u32 parent, u32 handle,
1255 struct nlattr **tca, int *errp,
1256 struct netlink_ext_ack *extack)
1257{
1258 int err;
1259 struct nlattr *kind = tca[TCA_KIND];
1260 struct Qdisc *sch;
1261 struct Qdisc_ops *ops;
1262 struct qdisc_size_table *stab;
1263
1264 ops = qdisc_lookup_ops(kind);
1265#ifdef CONFIG_MODULES
1266 if (ops == NULL && kind != NULL) {
1267 char name[IFNAMSIZ];
1268 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) {
1269 /* We dropped the RTNL semaphore in order to
1270 * perform the module load. So, even if we
1271 * succeeded in loading the module we have to
1272 * tell the caller to replay the request. We
1273 * indicate this using -EAGAIN.
1274 * We replay the request because the device may
1275 * go away in the mean time.
1276 */
1277 rtnl_unlock();
1278 request_module("sch_%s", name);
1279 rtnl_lock();
1280 ops = qdisc_lookup_ops(kind);
1281 if (ops != NULL) {
1282 /* We will try again qdisc_lookup_ops,
1283 * so don't keep a reference.
1284 */
1285 module_put(ops->owner);
1286 err = -EAGAIN;
1287 goto err_out;
1288 }
1289 }
1290 }
1291#endif
1292
1293 err = -ENOENT;
1294 if (!ops) {
1295 NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown");
1296 goto err_out;
1297 }
1298
1299 sch = qdisc_alloc(dev_queue, ops, extack);
1300 if (IS_ERR(sch)) {
1301 err = PTR_ERR(sch);
1302 goto err_out2;
1303 }
1304
1305 sch->parent = parent;
1306
1307 if (handle == TC_H_INGRESS) {
1308 if (!(sch->flags & TCQ_F_INGRESS)) {
1309 NL_SET_ERR_MSG(extack,
1310 "Specified parent ID is reserved for ingress and clsact Qdiscs");
1311 err = -EINVAL;
1312 goto err_out3;
1313 }
1314 handle = TC_H_MAKE(TC_H_INGRESS, 0);
1315 } else {
1316 if (handle == 0) {
1317 handle = qdisc_alloc_handle(dev);
1318 if (handle == 0) {
1319 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded");
1320 err = -ENOSPC;
1321 goto err_out3;
1322 }
1323 }
1324 if (!netif_is_multiqueue(dev))
1325 sch->flags |= TCQ_F_ONETXQUEUE;
1326 }
1327
1328 sch->handle = handle;
1329
1330 /* This exist to keep backward compatible with a userspace
1331 * loophole, what allowed userspace to get IFF_NO_QUEUE
1332 * facility on older kernels by setting tx_queue_len=0 (prior
1333 * to qdisc init), and then forgot to reinit tx_queue_len
1334 * before again attaching a qdisc.
1335 */
1336 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) {
1337 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
1338 netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
1339 }
1340
1341 err = qdisc_block_indexes_set(sch, tca, extack);
1342 if (err)
1343 goto err_out3;
1344
1345 if (tca[TCA_STAB]) {
1346 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1347 if (IS_ERR(stab)) {
1348 err = PTR_ERR(stab);
1349 goto err_out3;
1350 }
1351 rcu_assign_pointer(sch->stab, stab);
1352 }
1353
1354 if (ops->init) {
1355 err = ops->init(sch, tca[TCA_OPTIONS], extack);
1356 if (err != 0)
1357 goto err_out4;
1358 }
1359
1360 if (tca[TCA_RATE]) {
1361 err = -EOPNOTSUPP;
1362 if (sch->flags & TCQ_F_MQROOT) {
1363 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc");
1364 goto err_out4;
1365 }
1366
1367 err = gen_new_estimator(&sch->bstats,
1368 sch->cpu_bstats,
1369 &sch->rate_est,
1370 NULL,
1371 true,
1372 tca[TCA_RATE]);
1373 if (err) {
1374 NL_SET_ERR_MSG(extack, "Failed to generate new estimator");
1375 goto err_out4;
1376 }
1377 }
1378
1379 qdisc_hash_add(sch, false);
1380 trace_qdisc_create(ops, dev, parent);
1381
1382 return sch;
1383
1384err_out4:
1385 /* Even if ops->init() failed, we call ops->destroy()
1386 * like qdisc_create_dflt().
1387 */
1388 if (ops->destroy)
1389 ops->destroy(sch);
1390 qdisc_put_stab(rtnl_dereference(sch->stab));
1391err_out3:
1392 netdev_put(dev, &sch->dev_tracker);
1393 qdisc_free(sch);
1394err_out2:
1395 module_put(ops->owner);
1396err_out:
1397 *errp = err;
1398 return NULL;
1399}
1400
1401static int qdisc_change(struct Qdisc *sch, struct nlattr **tca,
1402 struct netlink_ext_ack *extack)
1403{
1404 struct qdisc_size_table *ostab, *stab = NULL;
1405 int err = 0;
1406
1407 if (tca[TCA_OPTIONS]) {
1408 if (!sch->ops->change) {
1409 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc");
1410 return -EINVAL;
1411 }
1412 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
1413 NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
1414 return -EOPNOTSUPP;
1415 }
1416 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack);
1417 if (err)
1418 return err;
1419 }
1420
1421 if (tca[TCA_STAB]) {
1422 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1423 if (IS_ERR(stab))
1424 return PTR_ERR(stab);
1425 }
1426
1427 ostab = rtnl_dereference(sch->stab);
1428 rcu_assign_pointer(sch->stab, stab);
1429 qdisc_put_stab(ostab);
1430
1431 if (tca[TCA_RATE]) {
1432 /* NB: ignores errors from replace_estimator
1433 because change can't be undone. */
1434 if (sch->flags & TCQ_F_MQROOT)
1435 goto out;
1436 gen_replace_estimator(&sch->bstats,
1437 sch->cpu_bstats,
1438 &sch->rate_est,
1439 NULL,
1440 true,
1441 tca[TCA_RATE]);
1442 }
1443out:
1444 return 0;
1445}
1446
1447struct check_loop_arg {
1448 struct qdisc_walker w;
1449 struct Qdisc *p;
1450 int depth;
1451};
1452
1453static int check_loop_fn(struct Qdisc *q, unsigned long cl,
1454 struct qdisc_walker *w);
1455
1456static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
1457{
1458 struct check_loop_arg arg;
1459
1460 if (q->ops->cl_ops == NULL)
1461 return 0;
1462
1463 arg.w.stop = arg.w.skip = arg.w.count = 0;
1464 arg.w.fn = check_loop_fn;
1465 arg.depth = depth;
1466 arg.p = p;
1467 q->ops->cl_ops->walk(q, &arg.w);
1468 return arg.w.stop ? -ELOOP : 0;
1469}
1470
1471static int
1472check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
1473{
1474 struct Qdisc *leaf;
1475 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1476 struct check_loop_arg *arg = (struct check_loop_arg *)w;
1477
1478 leaf = cops->leaf(q, cl);
1479 if (leaf) {
1480 if (leaf == arg->p || arg->depth > 7)
1481 return -ELOOP;
1482 return check_loop(leaf, arg->p, arg->depth + 1);
1483 }
1484 return 0;
1485}
1486
1487const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = {
1488 [TCA_KIND] = { .type = NLA_STRING },
1489 [TCA_RATE] = { .type = NLA_BINARY,
1490 .len = sizeof(struct tc_estimator) },
1491 [TCA_STAB] = { .type = NLA_NESTED },
1492 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG },
1493 [TCA_CHAIN] = { .type = NLA_U32 },
1494 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 },
1495 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 },
1496};
1497
1498/*
1499 * Delete/get qdisc.
1500 */
1501
1502static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1503 struct netlink_ext_ack *extack)
1504{
1505 struct net *net = sock_net(skb->sk);
1506 struct tcmsg *tcm = nlmsg_data(n);
1507 struct nlattr *tca[TCA_MAX + 1];
1508 struct net_device *dev;
1509 u32 clid;
1510 struct Qdisc *q = NULL;
1511 struct Qdisc *p = NULL;
1512 int err;
1513
1514 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1515 rtm_tca_policy, extack);
1516 if (err < 0)
1517 return err;
1518
1519 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1520 if (!dev)
1521 return -ENODEV;
1522
1523 clid = tcm->tcm_parent;
1524 if (clid) {
1525 if (clid != TC_H_ROOT) {
1526 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
1527 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1528 if (!p) {
1529 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid");
1530 return -ENOENT;
1531 }
1532 q = qdisc_leaf(p, clid);
1533 } else if (dev_ingress_queue(dev)) {
1534 q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
1535 }
1536 } else {
1537 q = rtnl_dereference(dev->qdisc);
1538 }
1539 if (!q) {
1540 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device");
1541 return -ENOENT;
1542 }
1543
1544 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) {
1545 NL_SET_ERR_MSG(extack, "Invalid handle");
1546 return -EINVAL;
1547 }
1548 } else {
1549 q = qdisc_lookup(dev, tcm->tcm_handle);
1550 if (!q) {
1551 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle");
1552 return -ENOENT;
1553 }
1554 }
1555
1556 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1557 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1558 return -EINVAL;
1559 }
1560
1561 if (n->nlmsg_type == RTM_DELQDISC) {
1562 if (!clid) {
1563 NL_SET_ERR_MSG(extack, "Classid cannot be zero");
1564 return -EINVAL;
1565 }
1566 if (q->handle == 0) {
1567 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero");
1568 return -ENOENT;
1569 }
1570 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack);
1571 if (err != 0)
1572 return err;
1573 } else {
1574 qdisc_get_notify(net, skb, n, clid, q, NULL);
1575 }
1576 return 0;
1577}
1578
1579static bool req_create_or_replace(struct nlmsghdr *n)
1580{
1581 return (n->nlmsg_flags & NLM_F_CREATE &&
1582 n->nlmsg_flags & NLM_F_REPLACE);
1583}
1584
1585static bool req_create_exclusive(struct nlmsghdr *n)
1586{
1587 return (n->nlmsg_flags & NLM_F_CREATE &&
1588 n->nlmsg_flags & NLM_F_EXCL);
1589}
1590
1591static bool req_change(struct nlmsghdr *n)
1592{
1593 return (!(n->nlmsg_flags & NLM_F_CREATE) &&
1594 !(n->nlmsg_flags & NLM_F_REPLACE) &&
1595 !(n->nlmsg_flags & NLM_F_EXCL));
1596}
1597
1598/*
1599 * Create/change qdisc.
1600 */
1601static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1602 struct netlink_ext_ack *extack)
1603{
1604 struct net *net = sock_net(skb->sk);
1605 struct tcmsg *tcm;
1606 struct nlattr *tca[TCA_MAX + 1];
1607 struct net_device *dev;
1608 u32 clid;
1609 struct Qdisc *q, *p;
1610 int err;
1611
1612replay:
1613 /* Reinit, just in case something touches this. */
1614 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1615 rtm_tca_policy, extack);
1616 if (err < 0)
1617 return err;
1618
1619 tcm = nlmsg_data(n);
1620 clid = tcm->tcm_parent;
1621 q = p = NULL;
1622
1623 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1624 if (!dev)
1625 return -ENODEV;
1626
1627
1628 if (clid) {
1629 if (clid != TC_H_ROOT) {
1630 if (clid != TC_H_INGRESS) {
1631 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1632 if (!p) {
1633 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc");
1634 return -ENOENT;
1635 }
1636 q = qdisc_leaf(p, clid);
1637 } else if (dev_ingress_queue_create(dev)) {
1638 q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
1639 }
1640 } else {
1641 q = rtnl_dereference(dev->qdisc);
1642 }
1643
1644 /* It may be default qdisc, ignore it */
1645 if (q && q->handle == 0)
1646 q = NULL;
1647
1648 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1649 if (tcm->tcm_handle) {
1650 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) {
1651 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override");
1652 return -EEXIST;
1653 }
1654 if (TC_H_MIN(tcm->tcm_handle)) {
1655 NL_SET_ERR_MSG(extack, "Invalid minor handle");
1656 return -EINVAL;
1657 }
1658 q = qdisc_lookup(dev, tcm->tcm_handle);
1659 if (!q)
1660 goto create_n_graft;
1661 if (n->nlmsg_flags & NLM_F_EXCL) {
1662 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override");
1663 return -EEXIST;
1664 }
1665 if (tca[TCA_KIND] &&
1666 nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1667 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1668 return -EINVAL;
1669 }
1670 if (q->flags & TCQ_F_INGRESS) {
1671 NL_SET_ERR_MSG(extack,
1672 "Cannot regraft ingress or clsact Qdiscs");
1673 return -EINVAL;
1674 }
1675 if (q == p ||
1676 (p && check_loop(q, p, 0))) {
1677 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected");
1678 return -ELOOP;
1679 }
1680 if (clid == TC_H_INGRESS) {
1681 NL_SET_ERR_MSG(extack, "Ingress cannot graft directly");
1682 return -EINVAL;
1683 }
1684 qdisc_refcount_inc(q);
1685 goto graft;
1686 } else {
1687 if (!q)
1688 goto create_n_graft;
1689
1690 /* This magic test requires explanation.
1691 *
1692 * We know, that some child q is already
1693 * attached to this parent and have choice:
1694 * 1) change it or 2) create/graft new one.
1695 * If the requested qdisc kind is different
1696 * than the existing one, then we choose graft.
1697 * If they are the same then this is "change"
1698 * operation - just let it fallthrough..
1699 *
1700 * 1. We are allowed to create/graft only
1701 * if the request is explicitly stating
1702 * "please create if it doesn't exist".
1703 *
1704 * 2. If the request is to exclusive create
1705 * then the qdisc tcm_handle is not expected
1706 * to exist, so that we choose create/graft too.
1707 *
1708 * 3. The last case is when no flags are set.
1709 * This will happen when for example tc
1710 * utility issues a "change" command.
1711 * Alas, it is sort of hole in API, we
1712 * cannot decide what to do unambiguously.
1713 * For now we select create/graft.
1714 */
1715 if (tca[TCA_KIND] &&
1716 nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1717 if (req_create_or_replace(n) ||
1718 req_create_exclusive(n))
1719 goto create_n_graft;
1720 else if (req_change(n))
1721 goto create_n_graft2;
1722 }
1723 }
1724 }
1725 } else {
1726 if (!tcm->tcm_handle) {
1727 NL_SET_ERR_MSG(extack, "Handle cannot be zero");
1728 return -EINVAL;
1729 }
1730 q = qdisc_lookup(dev, tcm->tcm_handle);
1731 }
1732
1733 /* Change qdisc parameters */
1734 if (!q) {
1735 NL_SET_ERR_MSG(extack, "Specified qdisc not found");
1736 return -ENOENT;
1737 }
1738 if (n->nlmsg_flags & NLM_F_EXCL) {
1739 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify");
1740 return -EEXIST;
1741 }
1742 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1743 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1744 return -EINVAL;
1745 }
1746 err = qdisc_change(q, tca, extack);
1747 if (err == 0)
1748 qdisc_notify(net, skb, n, clid, NULL, q, extack);
1749 return err;
1750
1751create_n_graft:
1752 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
1753 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag");
1754 return -ENOENT;
1755 }
1756create_n_graft2:
1757 if (clid == TC_H_INGRESS) {
1758 if (dev_ingress_queue(dev)) {
1759 q = qdisc_create(dev, dev_ingress_queue(dev),
1760 tcm->tcm_parent, tcm->tcm_parent,
1761 tca, &err, extack);
1762 } else {
1763 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device");
1764 err = -ENOENT;
1765 }
1766 } else {
1767 struct netdev_queue *dev_queue;
1768
1769 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1770 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1771 else if (p)
1772 dev_queue = p->dev_queue;
1773 else
1774 dev_queue = netdev_get_tx_queue(dev, 0);
1775
1776 q = qdisc_create(dev, dev_queue,
1777 tcm->tcm_parent, tcm->tcm_handle,
1778 tca, &err, extack);
1779 }
1780 if (q == NULL) {
1781 if (err == -EAGAIN)
1782 goto replay;
1783 return err;
1784 }
1785
1786graft:
1787 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack);
1788 if (err) {
1789 if (q)
1790 qdisc_put(q);
1791 return err;
1792 }
1793
1794 return 0;
1795}
1796
1797static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1798 struct netlink_callback *cb,
1799 int *q_idx_p, int s_q_idx, bool recur,
1800 bool dump_invisible)
1801{
1802 int ret = 0, q_idx = *q_idx_p;
1803 struct Qdisc *q;
1804 int b;
1805
1806 if (!root)
1807 return 0;
1808
1809 q = root;
1810 if (q_idx < s_q_idx) {
1811 q_idx++;
1812 } else {
1813 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1814 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1815 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1816 RTM_NEWQDISC, NULL) <= 0)
1817 goto done;
1818 q_idx++;
1819 }
1820
1821 /* If dumping singletons, there is no qdisc_dev(root) and the singleton
1822 * itself has already been dumped.
1823 *
1824 * If we've already dumped the top-level (ingress) qdisc above and the global
1825 * qdisc hashtable, we don't want to hit it again
1826 */
1827 if (!qdisc_dev(root) || !recur)
1828 goto out;
1829
1830 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1831 if (q_idx < s_q_idx) {
1832 q_idx++;
1833 continue;
1834 }
1835 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1836 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1837 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1838 RTM_NEWQDISC, NULL) <= 0)
1839 goto done;
1840 q_idx++;
1841 }
1842
1843out:
1844 *q_idx_p = q_idx;
1845 return ret;
1846done:
1847 ret = -1;
1848 goto out;
1849}
1850
1851static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1852{
1853 struct net *net = sock_net(skb->sk);
1854 int idx, q_idx;
1855 int s_idx, s_q_idx;
1856 struct net_device *dev;
1857 const struct nlmsghdr *nlh = cb->nlh;
1858 struct nlattr *tca[TCA_MAX + 1];
1859 int err;
1860
1861 s_idx = cb->args[0];
1862 s_q_idx = q_idx = cb->args[1];
1863
1864 idx = 0;
1865 ASSERT_RTNL();
1866
1867 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX,
1868 rtm_tca_policy, cb->extack);
1869 if (err < 0)
1870 return err;
1871
1872 for_each_netdev(net, dev) {
1873 struct netdev_queue *dev_queue;
1874
1875 if (idx < s_idx)
1876 goto cont;
1877 if (idx > s_idx)
1878 s_q_idx = 0;
1879 q_idx = 0;
1880
1881 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc),
1882 skb, cb, &q_idx, s_q_idx,
1883 true, tca[TCA_DUMP_INVISIBLE]) < 0)
1884 goto done;
1885
1886 dev_queue = dev_ingress_queue(dev);
1887 if (dev_queue &&
1888 tc_dump_qdisc_root(rtnl_dereference(dev_queue->qdisc_sleeping),
1889 skb, cb, &q_idx, s_q_idx, false,
1890 tca[TCA_DUMP_INVISIBLE]) < 0)
1891 goto done;
1892
1893cont:
1894 idx++;
1895 }
1896
1897done:
1898 cb->args[0] = idx;
1899 cb->args[1] = q_idx;
1900
1901 return skb->len;
1902}
1903
1904
1905
1906/************************************************
1907 * Traffic classes manipulation. *
1908 ************************************************/
1909
1910static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1911 unsigned long cl, u32 portid, u32 seq, u16 flags,
1912 int event, struct netlink_ext_ack *extack)
1913{
1914 struct tcmsg *tcm;
1915 struct nlmsghdr *nlh;
1916 unsigned char *b = skb_tail_pointer(skb);
1917 struct gnet_dump d;
1918 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1919
1920 cond_resched();
1921 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1922 if (!nlh)
1923 goto out_nlmsg_trim;
1924 tcm = nlmsg_data(nlh);
1925 tcm->tcm_family = AF_UNSPEC;
1926 tcm->tcm__pad1 = 0;
1927 tcm->tcm__pad2 = 0;
1928 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1929 tcm->tcm_parent = q->handle;
1930 tcm->tcm_handle = q->handle;
1931 tcm->tcm_info = 0;
1932 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1933 goto nla_put_failure;
1934 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1935 goto nla_put_failure;
1936
1937 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1938 NULL, &d, TCA_PAD) < 0)
1939 goto nla_put_failure;
1940
1941 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1942 goto nla_put_failure;
1943
1944 if (gnet_stats_finish_copy(&d) < 0)
1945 goto nla_put_failure;
1946
1947 if (extack && extack->_msg &&
1948 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
1949 goto out_nlmsg_trim;
1950
1951 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1952
1953 return skb->len;
1954
1955out_nlmsg_trim:
1956nla_put_failure:
1957 nlmsg_trim(skb, b);
1958 return -1;
1959}
1960
1961static int tclass_notify(struct net *net, struct sk_buff *oskb,
1962 struct nlmsghdr *n, struct Qdisc *q,
1963 unsigned long cl, int event, struct netlink_ext_ack *extack)
1964{
1965 struct sk_buff *skb;
1966 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1967
1968 if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
1969 return 0;
1970
1971 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1972 if (!skb)
1973 return -ENOBUFS;
1974
1975 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event, extack) < 0) {
1976 kfree_skb(skb);
1977 return -EINVAL;
1978 }
1979
1980 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1981 n->nlmsg_flags & NLM_F_ECHO);
1982}
1983
1984static int tclass_get_notify(struct net *net, struct sk_buff *oskb,
1985 struct nlmsghdr *n, struct Qdisc *q,
1986 unsigned long cl, struct netlink_ext_ack *extack)
1987{
1988 struct sk_buff *skb;
1989 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1990
1991 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1992 if (!skb)
1993 return -ENOBUFS;
1994
1995 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, RTM_NEWTCLASS,
1996 extack) < 0) {
1997 kfree_skb(skb);
1998 return -EINVAL;
1999 }
2000
2001 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2002 n->nlmsg_flags & NLM_F_ECHO);
2003}
2004
2005static int tclass_del_notify(struct net *net,
2006 const struct Qdisc_class_ops *cops,
2007 struct sk_buff *oskb, struct nlmsghdr *n,
2008 struct Qdisc *q, unsigned long cl,
2009 struct netlink_ext_ack *extack)
2010{
2011 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2012 struct sk_buff *skb;
2013 int err = 0;
2014
2015 if (!cops->delete)
2016 return -EOPNOTSUPP;
2017
2018 if (rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2019 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2020 if (!skb)
2021 return -ENOBUFS;
2022
2023 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0,
2024 RTM_DELTCLASS, extack) < 0) {
2025 kfree_skb(skb);
2026 return -EINVAL;
2027 }
2028 } else {
2029 skb = NULL;
2030 }
2031
2032 err = cops->delete(q, cl, extack);
2033 if (err) {
2034 kfree_skb(skb);
2035 return err;
2036 }
2037
2038 err = rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2039 n->nlmsg_flags & NLM_F_ECHO);
2040 return err;
2041}
2042
2043#ifdef CONFIG_NET_CLS
2044
2045struct tcf_bind_args {
2046 struct tcf_walker w;
2047 unsigned long base;
2048 unsigned long cl;
2049 u32 classid;
2050};
2051
2052static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2053{
2054 struct tcf_bind_args *a = (void *)arg;
2055
2056 if (n && tp->ops->bind_class) {
2057 struct Qdisc *q = tcf_block_q(tp->chain->block);
2058
2059 sch_tree_lock(q);
2060 tp->ops->bind_class(n, a->classid, a->cl, q, a->base);
2061 sch_tree_unlock(q);
2062 }
2063 return 0;
2064}
2065
2066struct tc_bind_class_args {
2067 struct qdisc_walker w;
2068 unsigned long new_cl;
2069 u32 portid;
2070 u32 clid;
2071};
2072
2073static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl,
2074 struct qdisc_walker *w)
2075{
2076 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w;
2077 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
2078 struct tcf_block *block;
2079 struct tcf_chain *chain;
2080
2081 block = cops->tcf_block(q, cl, NULL);
2082 if (!block)
2083 return 0;
2084 for (chain = tcf_get_next_chain(block, NULL);
2085 chain;
2086 chain = tcf_get_next_chain(block, chain)) {
2087 struct tcf_proto *tp;
2088
2089 for (tp = tcf_get_next_proto(chain, NULL);
2090 tp; tp = tcf_get_next_proto(chain, tp)) {
2091 struct tcf_bind_args arg = {};
2092
2093 arg.w.fn = tcf_node_bind;
2094 arg.classid = a->clid;
2095 arg.base = cl;
2096 arg.cl = a->new_cl;
2097 tp->ops->walk(tp, &arg.w, true);
2098 }
2099 }
2100
2101 return 0;
2102}
2103
2104static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
2105 unsigned long new_cl)
2106{
2107 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
2108 struct tc_bind_class_args args = {};
2109
2110 if (!cops->tcf_block)
2111 return;
2112 args.portid = portid;
2113 args.clid = clid;
2114 args.new_cl = new_cl;
2115 args.w.fn = tc_bind_class_walker;
2116 q->ops->cl_ops->walk(q, &args.w);
2117}
2118
2119#else
2120
2121static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
2122 unsigned long new_cl)
2123{
2124}
2125
2126#endif
2127
2128static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n,
2129 struct netlink_ext_ack *extack)
2130{
2131 struct net *net = sock_net(skb->sk);
2132 struct tcmsg *tcm = nlmsg_data(n);
2133 struct nlattr *tca[TCA_MAX + 1];
2134 struct net_device *dev;
2135 struct Qdisc *q = NULL;
2136 const struct Qdisc_class_ops *cops;
2137 unsigned long cl = 0;
2138 unsigned long new_cl;
2139 u32 portid;
2140 u32 clid;
2141 u32 qid;
2142 int err;
2143
2144 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
2145 rtm_tca_policy, extack);
2146 if (err < 0)
2147 return err;
2148
2149 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2150 if (!dev)
2151 return -ENODEV;
2152
2153 /*
2154 parent == TC_H_UNSPEC - unspecified parent.
2155 parent == TC_H_ROOT - class is root, which has no parent.
2156 parent == X:0 - parent is root class.
2157 parent == X:Y - parent is a node in hierarchy.
2158 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
2159
2160 handle == 0:0 - generate handle from kernel pool.
2161 handle == 0:Y - class is X:Y, where X:0 is qdisc.
2162 handle == X:Y - clear.
2163 handle == X:0 - root class.
2164 */
2165
2166 /* Step 1. Determine qdisc handle X:0 */
2167
2168 portid = tcm->tcm_parent;
2169 clid = tcm->tcm_handle;
2170 qid = TC_H_MAJ(clid);
2171
2172 if (portid != TC_H_ROOT) {
2173 u32 qid1 = TC_H_MAJ(portid);
2174
2175 if (qid && qid1) {
2176 /* If both majors are known, they must be identical. */
2177 if (qid != qid1)
2178 return -EINVAL;
2179 } else if (qid1) {
2180 qid = qid1;
2181 } else if (qid == 0)
2182 qid = rtnl_dereference(dev->qdisc)->handle;
2183
2184 /* Now qid is genuine qdisc handle consistent
2185 * both with parent and child.
2186 *
2187 * TC_H_MAJ(portid) still may be unspecified, complete it now.
2188 */
2189 if (portid)
2190 portid = TC_H_MAKE(qid, portid);
2191 } else {
2192 if (qid == 0)
2193 qid = rtnl_dereference(dev->qdisc)->handle;
2194 }
2195
2196 /* OK. Locate qdisc */
2197 q = qdisc_lookup(dev, qid);
2198 if (!q)
2199 return -ENOENT;
2200
2201 /* An check that it supports classes */
2202 cops = q->ops->cl_ops;
2203 if (cops == NULL)
2204 return -EINVAL;
2205
2206 /* Now try to get class */
2207 if (clid == 0) {
2208 if (portid == TC_H_ROOT)
2209 clid = qid;
2210 } else
2211 clid = TC_H_MAKE(qid, clid);
2212
2213 if (clid)
2214 cl = cops->find(q, clid);
2215
2216 if (cl == 0) {
2217 err = -ENOENT;
2218 if (n->nlmsg_type != RTM_NEWTCLASS ||
2219 !(n->nlmsg_flags & NLM_F_CREATE))
2220 goto out;
2221 } else {
2222 switch (n->nlmsg_type) {
2223 case RTM_NEWTCLASS:
2224 err = -EEXIST;
2225 if (n->nlmsg_flags & NLM_F_EXCL)
2226 goto out;
2227 break;
2228 case RTM_DELTCLASS:
2229 err = tclass_del_notify(net, cops, skb, n, q, cl, extack);
2230 /* Unbind the class with flilters with 0 */
2231 tc_bind_tclass(q, portid, clid, 0);
2232 goto out;
2233 case RTM_GETTCLASS:
2234 err = tclass_get_notify(net, skb, n, q, cl, extack);
2235 goto out;
2236 default:
2237 err = -EINVAL;
2238 goto out;
2239 }
2240 }
2241
2242 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
2243 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes");
2244 return -EOPNOTSUPP;
2245 }
2246
2247 new_cl = cl;
2248 err = -EOPNOTSUPP;
2249 if (cops->change)
2250 err = cops->change(q, clid, portid, tca, &new_cl, extack);
2251 if (err == 0) {
2252 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack);
2253 /* We just create a new class, need to do reverse binding. */
2254 if (cl != new_cl)
2255 tc_bind_tclass(q, portid, clid, new_cl);
2256 }
2257out:
2258 return err;
2259}
2260
2261struct qdisc_dump_args {
2262 struct qdisc_walker w;
2263 struct sk_buff *skb;
2264 struct netlink_callback *cb;
2265};
2266
2267static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
2268 struct qdisc_walker *arg)
2269{
2270 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
2271
2272 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
2273 a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2274 RTM_NEWTCLASS, NULL);
2275}
2276
2277static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
2278 struct tcmsg *tcm, struct netlink_callback *cb,
2279 int *t_p, int s_t)
2280{
2281 struct qdisc_dump_args arg;
2282
2283 if (tc_qdisc_dump_ignore(q, false) ||
2284 *t_p < s_t || !q->ops->cl_ops ||
2285 (tcm->tcm_parent &&
2286 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
2287 (*t_p)++;
2288 return 0;
2289 }
2290 if (*t_p > s_t)
2291 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
2292 arg.w.fn = qdisc_class_dump;
2293 arg.skb = skb;
2294 arg.cb = cb;
2295 arg.w.stop = 0;
2296 arg.w.skip = cb->args[1];
2297 arg.w.count = 0;
2298 q->ops->cl_ops->walk(q, &arg.w);
2299 cb->args[1] = arg.w.count;
2300 if (arg.w.stop)
2301 return -1;
2302 (*t_p)++;
2303 return 0;
2304}
2305
2306static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
2307 struct tcmsg *tcm, struct netlink_callback *cb,
2308 int *t_p, int s_t, bool recur)
2309{
2310 struct Qdisc *q;
2311 int b;
2312
2313 if (!root)
2314 return 0;
2315
2316 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
2317 return -1;
2318
2319 if (!qdisc_dev(root) || !recur)
2320 return 0;
2321
2322 if (tcm->tcm_parent) {
2323 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
2324 if (q && q != root &&
2325 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2326 return -1;
2327 return 0;
2328 }
2329 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
2330 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2331 return -1;
2332 }
2333
2334 return 0;
2335}
2336
2337static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
2338{
2339 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2340 struct net *net = sock_net(skb->sk);
2341 struct netdev_queue *dev_queue;
2342 struct net_device *dev;
2343 int t, s_t;
2344
2345 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2346 return 0;
2347 dev = dev_get_by_index(net, tcm->tcm_ifindex);
2348 if (!dev)
2349 return 0;
2350
2351 s_t = cb->args[0];
2352 t = 0;
2353
2354 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc),
2355 skb, tcm, cb, &t, s_t, true) < 0)
2356 goto done;
2357
2358 dev_queue = dev_ingress_queue(dev);
2359 if (dev_queue &&
2360 tc_dump_tclass_root(rtnl_dereference(dev_queue->qdisc_sleeping),
2361 skb, tcm, cb, &t, s_t, false) < 0)
2362 goto done;
2363
2364done:
2365 cb->args[0] = t;
2366
2367 dev_put(dev);
2368 return skb->len;
2369}
2370
2371#ifdef CONFIG_PROC_FS
2372static int psched_show(struct seq_file *seq, void *v)
2373{
2374 seq_printf(seq, "%08x %08x %08x %08x\n",
2375 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
2376 1000000,
2377 (u32)NSEC_PER_SEC / hrtimer_resolution);
2378
2379 return 0;
2380}
2381
2382static int __net_init psched_net_init(struct net *net)
2383{
2384 struct proc_dir_entry *e;
2385
2386 e = proc_create_single("psched", 0, net->proc_net, psched_show);
2387 if (e == NULL)
2388 return -ENOMEM;
2389
2390 return 0;
2391}
2392
2393static void __net_exit psched_net_exit(struct net *net)
2394{
2395 remove_proc_entry("psched", net->proc_net);
2396}
2397#else
2398static int __net_init psched_net_init(struct net *net)
2399{
2400 return 0;
2401}
2402
2403static void __net_exit psched_net_exit(struct net *net)
2404{
2405}
2406#endif
2407
2408static struct pernet_operations psched_net_ops = {
2409 .init = psched_net_init,
2410 .exit = psched_net_exit,
2411};
2412
2413#if IS_ENABLED(CONFIG_RETPOLINE)
2414DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper);
2415#endif
2416
2417static int __init pktsched_init(void)
2418{
2419 int err;
2420
2421 err = register_pernet_subsys(&psched_net_ops);
2422 if (err) {
2423 pr_err("pktsched_init: "
2424 "cannot initialize per netns operations\n");
2425 return err;
2426 }
2427
2428 register_qdisc(&pfifo_fast_ops);
2429 register_qdisc(&pfifo_qdisc_ops);
2430 register_qdisc(&bfifo_qdisc_ops);
2431 register_qdisc(&pfifo_head_drop_qdisc_ops);
2432 register_qdisc(&mq_qdisc_ops);
2433 register_qdisc(&noqueue_qdisc_ops);
2434
2435 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0);
2436 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0);
2437 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
2438 0);
2439 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0);
2440 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0);
2441 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
2442 0);
2443
2444 tc_wrapper_init();
2445
2446 return 0;
2447}
2448
2449subsys_initcall(pktsched_init);