Loading...
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(NET_SCH_ALIAS_PREFIX "%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}
596
597void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc)
598{
599 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
600 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
601 txt, qdisc->ops->id, qdisc->handle >> 16);
602 qdisc->flags |= TCQ_F_WARN_NONWC;
603 }
604}
605EXPORT_SYMBOL(qdisc_warn_nonwc);
606
607static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
608{
609 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
610 timer);
611
612 rcu_read_lock();
613 __netif_schedule(qdisc_root(wd->qdisc));
614 rcu_read_unlock();
615
616 return HRTIMER_NORESTART;
617}
618
619void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
620 clockid_t clockid)
621{
622 hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED);
623 wd->timer.function = qdisc_watchdog;
624 wd->qdisc = qdisc;
625}
626EXPORT_SYMBOL(qdisc_watchdog_init_clockid);
627
628void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
629{
630 qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC);
631}
632EXPORT_SYMBOL(qdisc_watchdog_init);
633
634void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
635 u64 delta_ns)
636{
637 bool deactivated;
638
639 rcu_read_lock();
640 deactivated = test_bit(__QDISC_STATE_DEACTIVATED,
641 &qdisc_root_sleeping(wd->qdisc)->state);
642 rcu_read_unlock();
643 if (deactivated)
644 return;
645
646 if (hrtimer_is_queued(&wd->timer)) {
647 u64 softexpires;
648
649 softexpires = ktime_to_ns(hrtimer_get_softexpires(&wd->timer));
650 /* If timer is already set in [expires, expires + delta_ns],
651 * do not reprogram it.
652 */
653 if (softexpires - expires <= delta_ns)
654 return;
655 }
656
657 hrtimer_start_range_ns(&wd->timer,
658 ns_to_ktime(expires),
659 delta_ns,
660 HRTIMER_MODE_ABS_PINNED);
661}
662EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns);
663
664void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
665{
666 hrtimer_cancel(&wd->timer);
667}
668EXPORT_SYMBOL(qdisc_watchdog_cancel);
669
670static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
671{
672 struct hlist_head *h;
673 unsigned int i;
674
675 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL);
676
677 if (h != NULL) {
678 for (i = 0; i < n; i++)
679 INIT_HLIST_HEAD(&h[i]);
680 }
681 return h;
682}
683
684void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
685{
686 struct Qdisc_class_common *cl;
687 struct hlist_node *next;
688 struct hlist_head *nhash, *ohash;
689 unsigned int nsize, nmask, osize;
690 unsigned int i, h;
691
692 /* Rehash when load factor exceeds 0.75 */
693 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
694 return;
695 nsize = clhash->hashsize * 2;
696 nmask = nsize - 1;
697 nhash = qdisc_class_hash_alloc(nsize);
698 if (nhash == NULL)
699 return;
700
701 ohash = clhash->hash;
702 osize = clhash->hashsize;
703
704 sch_tree_lock(sch);
705 for (i = 0; i < osize; i++) {
706 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
707 h = qdisc_class_hash(cl->classid, nmask);
708 hlist_add_head(&cl->hnode, &nhash[h]);
709 }
710 }
711 clhash->hash = nhash;
712 clhash->hashsize = nsize;
713 clhash->hashmask = nmask;
714 sch_tree_unlock(sch);
715
716 kvfree(ohash);
717}
718EXPORT_SYMBOL(qdisc_class_hash_grow);
719
720int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
721{
722 unsigned int size = 4;
723
724 clhash->hash = qdisc_class_hash_alloc(size);
725 if (!clhash->hash)
726 return -ENOMEM;
727 clhash->hashsize = size;
728 clhash->hashmask = size - 1;
729 clhash->hashelems = 0;
730 return 0;
731}
732EXPORT_SYMBOL(qdisc_class_hash_init);
733
734void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
735{
736 kvfree(clhash->hash);
737}
738EXPORT_SYMBOL(qdisc_class_hash_destroy);
739
740void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
741 struct Qdisc_class_common *cl)
742{
743 unsigned int h;
744
745 INIT_HLIST_NODE(&cl->hnode);
746 h = qdisc_class_hash(cl->classid, clhash->hashmask);
747 hlist_add_head(&cl->hnode, &clhash->hash[h]);
748 clhash->hashelems++;
749}
750EXPORT_SYMBOL(qdisc_class_hash_insert);
751
752void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
753 struct Qdisc_class_common *cl)
754{
755 hlist_del(&cl->hnode);
756 clhash->hashelems--;
757}
758EXPORT_SYMBOL(qdisc_class_hash_remove);
759
760/* Allocate an unique handle from space managed by kernel
761 * Possible range is [8000-FFFF]:0000 (0x8000 values)
762 */
763static u32 qdisc_alloc_handle(struct net_device *dev)
764{
765 int i = 0x8000;
766 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
767
768 do {
769 autohandle += TC_H_MAKE(0x10000U, 0);
770 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
771 autohandle = TC_H_MAKE(0x80000000U, 0);
772 if (!qdisc_lookup(dev, autohandle))
773 return autohandle;
774 cond_resched();
775 } while (--i > 0);
776
777 return 0;
778}
779
780void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len)
781{
782 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED;
783 const struct Qdisc_class_ops *cops;
784 unsigned long cl;
785 u32 parentid;
786 bool notify;
787 int drops;
788
789 if (n == 0 && len == 0)
790 return;
791 drops = max_t(int, n, 0);
792 rcu_read_lock();
793 while ((parentid = sch->parent)) {
794 if (parentid == TC_H_ROOT)
795 break;
796
797 if (sch->flags & TCQ_F_NOPARENT)
798 break;
799 /* Notify parent qdisc only if child qdisc becomes empty.
800 *
801 * If child was empty even before update then backlog
802 * counter is screwed and we skip notification because
803 * parent class is already passive.
804 *
805 * If the original child was offloaded then it is allowed
806 * to be seem as empty, so the parent is notified anyway.
807 */
808 notify = !sch->q.qlen && !WARN_ON_ONCE(!n &&
809 !qdisc_is_offloaded);
810 /* TODO: perform the search on a per txq basis */
811 sch = qdisc_lookup_rcu(qdisc_dev(sch), TC_H_MAJ(parentid));
812 if (sch == NULL) {
813 WARN_ON_ONCE(parentid != TC_H_ROOT);
814 break;
815 }
816 cops = sch->ops->cl_ops;
817 if (notify && cops->qlen_notify) {
818 cl = cops->find(sch, parentid);
819 cops->qlen_notify(sch, cl);
820 }
821 sch->q.qlen -= n;
822 sch->qstats.backlog -= len;
823 __qdisc_qstats_drop(sch, drops);
824 }
825 rcu_read_unlock();
826}
827EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
828
829int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type,
830 void *type_data)
831{
832 struct net_device *dev = qdisc_dev(sch);
833 int err;
834
835 sch->flags &= ~TCQ_F_OFFLOADED;
836 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
837 return 0;
838
839 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
840 if (err == -EOPNOTSUPP)
841 return 0;
842
843 if (!err)
844 sch->flags |= TCQ_F_OFFLOADED;
845
846 return err;
847}
848EXPORT_SYMBOL(qdisc_offload_dump_helper);
849
850void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
851 struct Qdisc *new, struct Qdisc *old,
852 enum tc_setup_type type, void *type_data,
853 struct netlink_ext_ack *extack)
854{
855 bool any_qdisc_is_offloaded;
856 int err;
857
858 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
859 return;
860
861 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
862
863 /* Don't report error if the graft is part of destroy operation. */
864 if (!err || !new || new == &noop_qdisc)
865 return;
866
867 /* Don't report error if the parent, the old child and the new
868 * one are not offloaded.
869 */
870 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED;
871 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED;
872 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED;
873
874 if (any_qdisc_is_offloaded)
875 NL_SET_ERR_MSG(extack, "Offloading graft operation failed.");
876}
877EXPORT_SYMBOL(qdisc_offload_graft_helper);
878
879void qdisc_offload_query_caps(struct net_device *dev,
880 enum tc_setup_type type,
881 void *caps, size_t caps_len)
882{
883 const struct net_device_ops *ops = dev->netdev_ops;
884 struct tc_query_caps_base base = {
885 .type = type,
886 .caps = caps,
887 };
888
889 memset(caps, 0, caps_len);
890
891 if (ops->ndo_setup_tc)
892 ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base);
893}
894EXPORT_SYMBOL(qdisc_offload_query_caps);
895
896static void qdisc_offload_graft_root(struct net_device *dev,
897 struct Qdisc *new, struct Qdisc *old,
898 struct netlink_ext_ack *extack)
899{
900 struct tc_root_qopt_offload graft_offload = {
901 .command = TC_ROOT_GRAFT,
902 .handle = new ? new->handle : 0,
903 .ingress = (new && new->flags & TCQ_F_INGRESS) ||
904 (old && old->flags & TCQ_F_INGRESS),
905 };
906
907 qdisc_offload_graft_helper(dev, NULL, new, old,
908 TC_SETUP_ROOT_QDISC, &graft_offload, extack);
909}
910
911static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
912 u32 portid, u32 seq, u16 flags, int event,
913 struct netlink_ext_ack *extack)
914{
915 struct gnet_stats_basic_sync __percpu *cpu_bstats = NULL;
916 struct gnet_stats_queue __percpu *cpu_qstats = NULL;
917 struct tcmsg *tcm;
918 struct nlmsghdr *nlh;
919 unsigned char *b = skb_tail_pointer(skb);
920 struct gnet_dump d;
921 struct qdisc_size_table *stab;
922 u32 block_index;
923 __u32 qlen;
924
925 cond_resched();
926 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
927 if (!nlh)
928 goto out_nlmsg_trim;
929 tcm = nlmsg_data(nlh);
930 tcm->tcm_family = AF_UNSPEC;
931 tcm->tcm__pad1 = 0;
932 tcm->tcm__pad2 = 0;
933 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
934 tcm->tcm_parent = clid;
935 tcm->tcm_handle = q->handle;
936 tcm->tcm_info = refcount_read(&q->refcnt);
937 if (nla_put_string(skb, TCA_KIND, q->ops->id))
938 goto nla_put_failure;
939 if (q->ops->ingress_block_get) {
940 block_index = q->ops->ingress_block_get(q);
941 if (block_index &&
942 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index))
943 goto nla_put_failure;
944 }
945 if (q->ops->egress_block_get) {
946 block_index = q->ops->egress_block_get(q);
947 if (block_index &&
948 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index))
949 goto nla_put_failure;
950 }
951 if (q->ops->dump && q->ops->dump(q, skb) < 0)
952 goto nla_put_failure;
953 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED)))
954 goto nla_put_failure;
955 qlen = qdisc_qlen_sum(q);
956
957 stab = rtnl_dereference(q->stab);
958 if (stab && qdisc_dump_stab(skb, stab) < 0)
959 goto nla_put_failure;
960
961 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
962 NULL, &d, TCA_PAD) < 0)
963 goto nla_put_failure;
964
965 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
966 goto nla_put_failure;
967
968 if (qdisc_is_percpu_stats(q)) {
969 cpu_bstats = q->cpu_bstats;
970 cpu_qstats = q->cpu_qstats;
971 }
972
973 if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats, true) < 0 ||
974 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
975 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
976 goto nla_put_failure;
977
978 if (gnet_stats_finish_copy(&d) < 0)
979 goto nla_put_failure;
980
981 if (extack && extack->_msg &&
982 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
983 goto out_nlmsg_trim;
984
985 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
986
987 return skb->len;
988
989out_nlmsg_trim:
990nla_put_failure:
991 nlmsg_trim(skb, b);
992 return -1;
993}
994
995static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible)
996{
997 if (q->flags & TCQ_F_BUILTIN)
998 return true;
999 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
1000 return true;
1001
1002 return false;
1003}
1004
1005static int qdisc_get_notify(struct net *net, struct sk_buff *oskb,
1006 struct nlmsghdr *n, u32 clid, struct Qdisc *q,
1007 struct netlink_ext_ack *extack)
1008{
1009 struct sk_buff *skb;
1010 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1011
1012 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1013 if (!skb)
1014 return -ENOBUFS;
1015
1016 if (!tc_qdisc_dump_ignore(q, false)) {
1017 if (tc_fill_qdisc(skb, q, clid, portid, n->nlmsg_seq, 0,
1018 RTM_NEWQDISC, extack) < 0)
1019 goto err_out;
1020 }
1021
1022 if (skb->len)
1023 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1024 n->nlmsg_flags & NLM_F_ECHO);
1025
1026err_out:
1027 kfree_skb(skb);
1028 return -EINVAL;
1029}
1030
1031static int qdisc_notify(struct net *net, struct sk_buff *oskb,
1032 struct nlmsghdr *n, u32 clid,
1033 struct Qdisc *old, struct Qdisc *new,
1034 struct netlink_ext_ack *extack)
1035{
1036 struct sk_buff *skb;
1037 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1038
1039 if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
1040 return 0;
1041
1042 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1043 if (!skb)
1044 return -ENOBUFS;
1045
1046 if (old && !tc_qdisc_dump_ignore(old, false)) {
1047 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
1048 0, RTM_DELQDISC, extack) < 0)
1049 goto err_out;
1050 }
1051 if (new && !tc_qdisc_dump_ignore(new, false)) {
1052 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
1053 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC, extack) < 0)
1054 goto err_out;
1055 }
1056
1057 if (skb->len)
1058 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1059 n->nlmsg_flags & NLM_F_ECHO);
1060
1061err_out:
1062 kfree_skb(skb);
1063 return -EINVAL;
1064}
1065
1066static void notify_and_destroy(struct net *net, struct sk_buff *skb,
1067 struct nlmsghdr *n, u32 clid,
1068 struct Qdisc *old, struct Qdisc *new,
1069 struct netlink_ext_ack *extack)
1070{
1071 if (new || old)
1072 qdisc_notify(net, skb, n, clid, old, new, extack);
1073
1074 if (old)
1075 qdisc_put(old);
1076}
1077
1078static void qdisc_clear_nolock(struct Qdisc *sch)
1079{
1080 sch->flags &= ~TCQ_F_NOLOCK;
1081 if (!(sch->flags & TCQ_F_CPUSTATS))
1082 return;
1083
1084 free_percpu(sch->cpu_bstats);
1085 free_percpu(sch->cpu_qstats);
1086 sch->cpu_bstats = NULL;
1087 sch->cpu_qstats = NULL;
1088 sch->flags &= ~TCQ_F_CPUSTATS;
1089}
1090
1091/* Graft qdisc "new" to class "classid" of qdisc "parent" or
1092 * to device "dev".
1093 *
1094 * When appropriate send a netlink notification using 'skb'
1095 * and "n".
1096 *
1097 * On success, destroy old qdisc.
1098 */
1099
1100static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
1101 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
1102 struct Qdisc *new, struct Qdisc *old,
1103 struct netlink_ext_ack *extack)
1104{
1105 struct Qdisc *q = old;
1106 struct net *net = dev_net(dev);
1107
1108 if (parent == NULL) {
1109 unsigned int i, num_q, ingress;
1110 struct netdev_queue *dev_queue;
1111
1112 ingress = 0;
1113 num_q = dev->num_tx_queues;
1114 if ((q && q->flags & TCQ_F_INGRESS) ||
1115 (new && new->flags & TCQ_F_INGRESS)) {
1116 ingress = 1;
1117 dev_queue = dev_ingress_queue(dev);
1118 if (!dev_queue) {
1119 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue");
1120 return -ENOENT;
1121 }
1122
1123 q = rtnl_dereference(dev_queue->qdisc_sleeping);
1124
1125 /* This is the counterpart of that qdisc_refcount_inc_nz() call in
1126 * __tcf_qdisc_find() for filter requests.
1127 */
1128 if (!qdisc_refcount_dec_if_one(q)) {
1129 NL_SET_ERR_MSG(extack,
1130 "Current ingress or clsact Qdisc has ongoing filter requests");
1131 return -EBUSY;
1132 }
1133 }
1134
1135 if (dev->flags & IFF_UP)
1136 dev_deactivate(dev);
1137
1138 qdisc_offload_graft_root(dev, new, old, extack);
1139
1140 if (new && new->ops->attach && !ingress)
1141 goto skip;
1142
1143 if (!ingress) {
1144 for (i = 0; i < num_q; i++) {
1145 dev_queue = netdev_get_tx_queue(dev, i);
1146 old = dev_graft_qdisc(dev_queue, new);
1147
1148 if (new && i > 0)
1149 qdisc_refcount_inc(new);
1150 qdisc_put(old);
1151 }
1152 } else {
1153 old = dev_graft_qdisc(dev_queue, NULL);
1154
1155 /* {ingress,clsact}_destroy() @old before grafting @new to avoid
1156 * unprotected concurrent accesses to net_device::miniq_{in,e}gress
1157 * pointer(s) in mini_qdisc_pair_swap().
1158 */
1159 qdisc_notify(net, skb, n, classid, old, new, extack);
1160 qdisc_destroy(old);
1161
1162 dev_graft_qdisc(dev_queue, new);
1163 }
1164
1165skip:
1166 if (!ingress) {
1167 old = rtnl_dereference(dev->qdisc);
1168 if (new && !new->ops->attach)
1169 qdisc_refcount_inc(new);
1170 rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc);
1171
1172 notify_and_destroy(net, skb, n, classid, old, new, extack);
1173
1174 if (new && new->ops->attach)
1175 new->ops->attach(new);
1176 }
1177
1178 if (dev->flags & IFF_UP)
1179 dev_activate(dev);
1180 } else {
1181 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
1182 unsigned long cl;
1183 int err;
1184
1185 /* Only support running class lockless if parent is lockless */
1186 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK))
1187 qdisc_clear_nolock(new);
1188
1189 if (!cops || !cops->graft)
1190 return -EOPNOTSUPP;
1191
1192 cl = cops->find(parent, classid);
1193 if (!cl) {
1194 NL_SET_ERR_MSG(extack, "Specified class not found");
1195 return -ENOENT;
1196 }
1197
1198 if (new && new->ops == &noqueue_qdisc_ops) {
1199 NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class");
1200 return -EINVAL;
1201 }
1202
1203 if (new &&
1204 !(parent->flags & TCQ_F_MQROOT) &&
1205 rcu_access_pointer(new->stab)) {
1206 NL_SET_ERR_MSG(extack, "STAB not supported on a non root");
1207 return -EINVAL;
1208 }
1209 err = cops->graft(parent, cl, new, &old, extack);
1210 if (err)
1211 return err;
1212 notify_and_destroy(net, skb, n, classid, old, new, extack);
1213 }
1214 return 0;
1215}
1216
1217static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca,
1218 struct netlink_ext_ack *extack)
1219{
1220 u32 block_index;
1221
1222 if (tca[TCA_INGRESS_BLOCK]) {
1223 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]);
1224
1225 if (!block_index) {
1226 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0");
1227 return -EINVAL;
1228 }
1229 if (!sch->ops->ingress_block_set) {
1230 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported");
1231 return -EOPNOTSUPP;
1232 }
1233 sch->ops->ingress_block_set(sch, block_index);
1234 }
1235 if (tca[TCA_EGRESS_BLOCK]) {
1236 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]);
1237
1238 if (!block_index) {
1239 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0");
1240 return -EINVAL;
1241 }
1242 if (!sch->ops->egress_block_set) {
1243 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported");
1244 return -EOPNOTSUPP;
1245 }
1246 sch->ops->egress_block_set(sch, block_index);
1247 }
1248 return 0;
1249}
1250
1251/*
1252 Allocate and initialize new qdisc.
1253
1254 Parameters are passed via opt.
1255 */
1256
1257static struct Qdisc *qdisc_create(struct net_device *dev,
1258 struct netdev_queue *dev_queue,
1259 u32 parent, u32 handle,
1260 struct nlattr **tca, int *errp,
1261 struct netlink_ext_ack *extack)
1262{
1263 int err;
1264 struct nlattr *kind = tca[TCA_KIND];
1265 struct Qdisc *sch;
1266 struct Qdisc_ops *ops;
1267 struct qdisc_size_table *stab;
1268
1269 ops = qdisc_lookup_ops(kind);
1270#ifdef CONFIG_MODULES
1271 if (ops == NULL && kind != NULL) {
1272 char name[IFNAMSIZ];
1273 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) {
1274 /* We dropped the RTNL semaphore in order to
1275 * perform the module load. So, even if we
1276 * succeeded in loading the module we have to
1277 * tell the caller to replay the request. We
1278 * indicate this using -EAGAIN.
1279 * We replay the request because the device may
1280 * go away in the mean time.
1281 */
1282 rtnl_unlock();
1283 request_module(NET_SCH_ALIAS_PREFIX "%s", name);
1284 rtnl_lock();
1285 ops = qdisc_lookup_ops(kind);
1286 if (ops != NULL) {
1287 /* We will try again qdisc_lookup_ops,
1288 * so don't keep a reference.
1289 */
1290 module_put(ops->owner);
1291 err = -EAGAIN;
1292 goto err_out;
1293 }
1294 }
1295 }
1296#endif
1297
1298 err = -ENOENT;
1299 if (!ops) {
1300 NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown");
1301 goto err_out;
1302 }
1303
1304 sch = qdisc_alloc(dev_queue, ops, extack);
1305 if (IS_ERR(sch)) {
1306 err = PTR_ERR(sch);
1307 goto err_out2;
1308 }
1309
1310 sch->parent = parent;
1311
1312 if (handle == TC_H_INGRESS) {
1313 if (!(sch->flags & TCQ_F_INGRESS)) {
1314 NL_SET_ERR_MSG(extack,
1315 "Specified parent ID is reserved for ingress and clsact Qdiscs");
1316 err = -EINVAL;
1317 goto err_out3;
1318 }
1319 handle = TC_H_MAKE(TC_H_INGRESS, 0);
1320 } else {
1321 if (handle == 0) {
1322 handle = qdisc_alloc_handle(dev);
1323 if (handle == 0) {
1324 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded");
1325 err = -ENOSPC;
1326 goto err_out3;
1327 }
1328 }
1329 if (!netif_is_multiqueue(dev))
1330 sch->flags |= TCQ_F_ONETXQUEUE;
1331 }
1332
1333 sch->handle = handle;
1334
1335 /* This exist to keep backward compatible with a userspace
1336 * loophole, what allowed userspace to get IFF_NO_QUEUE
1337 * facility on older kernels by setting tx_queue_len=0 (prior
1338 * to qdisc init), and then forgot to reinit tx_queue_len
1339 * before again attaching a qdisc.
1340 */
1341 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) {
1342 WRITE_ONCE(dev->tx_queue_len, DEFAULT_TX_QUEUE_LEN);
1343 netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
1344 }
1345
1346 err = qdisc_block_indexes_set(sch, tca, extack);
1347 if (err)
1348 goto err_out3;
1349
1350 if (tca[TCA_STAB]) {
1351 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1352 if (IS_ERR(stab)) {
1353 err = PTR_ERR(stab);
1354 goto err_out3;
1355 }
1356 rcu_assign_pointer(sch->stab, stab);
1357 }
1358
1359 if (ops->init) {
1360 err = ops->init(sch, tca[TCA_OPTIONS], extack);
1361 if (err != 0)
1362 goto err_out4;
1363 }
1364
1365 if (tca[TCA_RATE]) {
1366 err = -EOPNOTSUPP;
1367 if (sch->flags & TCQ_F_MQROOT) {
1368 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc");
1369 goto err_out4;
1370 }
1371
1372 err = gen_new_estimator(&sch->bstats,
1373 sch->cpu_bstats,
1374 &sch->rate_est,
1375 NULL,
1376 true,
1377 tca[TCA_RATE]);
1378 if (err) {
1379 NL_SET_ERR_MSG(extack, "Failed to generate new estimator");
1380 goto err_out4;
1381 }
1382 }
1383
1384 qdisc_hash_add(sch, false);
1385 trace_qdisc_create(ops, dev, parent);
1386
1387 return sch;
1388
1389err_out4:
1390 /* Even if ops->init() failed, we call ops->destroy()
1391 * like qdisc_create_dflt().
1392 */
1393 if (ops->destroy)
1394 ops->destroy(sch);
1395 qdisc_put_stab(rtnl_dereference(sch->stab));
1396err_out3:
1397 lockdep_unregister_key(&sch->root_lock_key);
1398 netdev_put(dev, &sch->dev_tracker);
1399 qdisc_free(sch);
1400err_out2:
1401 module_put(ops->owner);
1402err_out:
1403 *errp = err;
1404 return NULL;
1405}
1406
1407static int qdisc_change(struct Qdisc *sch, struct nlattr **tca,
1408 struct netlink_ext_ack *extack)
1409{
1410 struct qdisc_size_table *ostab, *stab = NULL;
1411 int err = 0;
1412
1413 if (tca[TCA_OPTIONS]) {
1414 if (!sch->ops->change) {
1415 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc");
1416 return -EINVAL;
1417 }
1418 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
1419 NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
1420 return -EOPNOTSUPP;
1421 }
1422 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack);
1423 if (err)
1424 return err;
1425 }
1426
1427 if (tca[TCA_STAB]) {
1428 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1429 if (IS_ERR(stab))
1430 return PTR_ERR(stab);
1431 }
1432
1433 ostab = rtnl_dereference(sch->stab);
1434 rcu_assign_pointer(sch->stab, stab);
1435 qdisc_put_stab(ostab);
1436
1437 if (tca[TCA_RATE]) {
1438 /* NB: ignores errors from replace_estimator
1439 because change can't be undone. */
1440 if (sch->flags & TCQ_F_MQROOT)
1441 goto out;
1442 gen_replace_estimator(&sch->bstats,
1443 sch->cpu_bstats,
1444 &sch->rate_est,
1445 NULL,
1446 true,
1447 tca[TCA_RATE]);
1448 }
1449out:
1450 return 0;
1451}
1452
1453struct check_loop_arg {
1454 struct qdisc_walker w;
1455 struct Qdisc *p;
1456 int depth;
1457};
1458
1459static int check_loop_fn(struct Qdisc *q, unsigned long cl,
1460 struct qdisc_walker *w);
1461
1462static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
1463{
1464 struct check_loop_arg arg;
1465
1466 if (q->ops->cl_ops == NULL)
1467 return 0;
1468
1469 arg.w.stop = arg.w.skip = arg.w.count = 0;
1470 arg.w.fn = check_loop_fn;
1471 arg.depth = depth;
1472 arg.p = p;
1473 q->ops->cl_ops->walk(q, &arg.w);
1474 return arg.w.stop ? -ELOOP : 0;
1475}
1476
1477static int
1478check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
1479{
1480 struct Qdisc *leaf;
1481 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1482 struct check_loop_arg *arg = (struct check_loop_arg *)w;
1483
1484 leaf = cops->leaf(q, cl);
1485 if (leaf) {
1486 if (leaf == arg->p || arg->depth > 7)
1487 return -ELOOP;
1488 return check_loop(leaf, arg->p, arg->depth + 1);
1489 }
1490 return 0;
1491}
1492
1493const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = {
1494 [TCA_KIND] = { .type = NLA_STRING },
1495 [TCA_RATE] = { .type = NLA_BINARY,
1496 .len = sizeof(struct tc_estimator) },
1497 [TCA_STAB] = { .type = NLA_NESTED },
1498 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG },
1499 [TCA_CHAIN] = { .type = NLA_U32 },
1500 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 },
1501 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 },
1502};
1503
1504/*
1505 * Delete/get qdisc.
1506 */
1507
1508static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1509 struct netlink_ext_ack *extack)
1510{
1511 struct net *net = sock_net(skb->sk);
1512 struct tcmsg *tcm = nlmsg_data(n);
1513 struct nlattr *tca[TCA_MAX + 1];
1514 struct net_device *dev;
1515 u32 clid;
1516 struct Qdisc *q = NULL;
1517 struct Qdisc *p = NULL;
1518 int err;
1519
1520 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1521 rtm_tca_policy, extack);
1522 if (err < 0)
1523 return err;
1524
1525 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1526 if (!dev)
1527 return -ENODEV;
1528
1529 clid = tcm->tcm_parent;
1530 if (clid) {
1531 if (clid != TC_H_ROOT) {
1532 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
1533 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1534 if (!p) {
1535 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid");
1536 return -ENOENT;
1537 }
1538 q = qdisc_leaf(p, clid);
1539 } else if (dev_ingress_queue(dev)) {
1540 q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
1541 }
1542 } else {
1543 q = rtnl_dereference(dev->qdisc);
1544 }
1545 if (!q) {
1546 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device");
1547 return -ENOENT;
1548 }
1549
1550 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) {
1551 NL_SET_ERR_MSG(extack, "Invalid handle");
1552 return -EINVAL;
1553 }
1554 } else {
1555 q = qdisc_lookup(dev, tcm->tcm_handle);
1556 if (!q) {
1557 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle");
1558 return -ENOENT;
1559 }
1560 }
1561
1562 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1563 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1564 return -EINVAL;
1565 }
1566
1567 if (n->nlmsg_type == RTM_DELQDISC) {
1568 if (!clid) {
1569 NL_SET_ERR_MSG(extack, "Classid cannot be zero");
1570 return -EINVAL;
1571 }
1572 if (q->handle == 0) {
1573 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero");
1574 return -ENOENT;
1575 }
1576 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack);
1577 if (err != 0)
1578 return err;
1579 } else {
1580 qdisc_get_notify(net, skb, n, clid, q, NULL);
1581 }
1582 return 0;
1583}
1584
1585static bool req_create_or_replace(struct nlmsghdr *n)
1586{
1587 return (n->nlmsg_flags & NLM_F_CREATE &&
1588 n->nlmsg_flags & NLM_F_REPLACE);
1589}
1590
1591static bool req_create_exclusive(struct nlmsghdr *n)
1592{
1593 return (n->nlmsg_flags & NLM_F_CREATE &&
1594 n->nlmsg_flags & NLM_F_EXCL);
1595}
1596
1597static bool req_change(struct nlmsghdr *n)
1598{
1599 return (!(n->nlmsg_flags & NLM_F_CREATE) &&
1600 !(n->nlmsg_flags & NLM_F_REPLACE) &&
1601 !(n->nlmsg_flags & NLM_F_EXCL));
1602}
1603
1604/*
1605 * Create/change qdisc.
1606 */
1607static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1608 struct netlink_ext_ack *extack)
1609{
1610 struct net *net = sock_net(skb->sk);
1611 struct tcmsg *tcm;
1612 struct nlattr *tca[TCA_MAX + 1];
1613 struct net_device *dev;
1614 u32 clid;
1615 struct Qdisc *q, *p;
1616 int err;
1617
1618replay:
1619 /* Reinit, just in case something touches this. */
1620 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1621 rtm_tca_policy, extack);
1622 if (err < 0)
1623 return err;
1624
1625 tcm = nlmsg_data(n);
1626 clid = tcm->tcm_parent;
1627 q = p = NULL;
1628
1629 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1630 if (!dev)
1631 return -ENODEV;
1632
1633
1634 if (clid) {
1635 if (clid != TC_H_ROOT) {
1636 if (clid != TC_H_INGRESS) {
1637 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1638 if (!p) {
1639 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc");
1640 return -ENOENT;
1641 }
1642 q = qdisc_leaf(p, clid);
1643 } else if (dev_ingress_queue_create(dev)) {
1644 q = rtnl_dereference(dev_ingress_queue(dev)->qdisc_sleeping);
1645 }
1646 } else {
1647 q = rtnl_dereference(dev->qdisc);
1648 }
1649
1650 /* It may be default qdisc, ignore it */
1651 if (q && q->handle == 0)
1652 q = NULL;
1653
1654 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1655 if (tcm->tcm_handle) {
1656 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) {
1657 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override");
1658 return -EEXIST;
1659 }
1660 if (TC_H_MIN(tcm->tcm_handle)) {
1661 NL_SET_ERR_MSG(extack, "Invalid minor handle");
1662 return -EINVAL;
1663 }
1664 q = qdisc_lookup(dev, tcm->tcm_handle);
1665 if (!q)
1666 goto create_n_graft;
1667 if (q->parent != tcm->tcm_parent) {
1668 NL_SET_ERR_MSG(extack, "Cannot move an existing qdisc to a different parent");
1669 return -EINVAL;
1670 }
1671 if (n->nlmsg_flags & NLM_F_EXCL) {
1672 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override");
1673 return -EEXIST;
1674 }
1675 if (tca[TCA_KIND] &&
1676 nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1677 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1678 return -EINVAL;
1679 }
1680 if (q->flags & TCQ_F_INGRESS) {
1681 NL_SET_ERR_MSG(extack,
1682 "Cannot regraft ingress or clsact Qdiscs");
1683 return -EINVAL;
1684 }
1685 if (q == p ||
1686 (p && check_loop(q, p, 0))) {
1687 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected");
1688 return -ELOOP;
1689 }
1690 if (clid == TC_H_INGRESS) {
1691 NL_SET_ERR_MSG(extack, "Ingress cannot graft directly");
1692 return -EINVAL;
1693 }
1694 qdisc_refcount_inc(q);
1695 goto graft;
1696 } else {
1697 if (!q)
1698 goto create_n_graft;
1699
1700 /* This magic test requires explanation.
1701 *
1702 * We know, that some child q is already
1703 * attached to this parent and have choice:
1704 * 1) change it or 2) create/graft new one.
1705 * If the requested qdisc kind is different
1706 * than the existing one, then we choose graft.
1707 * If they are the same then this is "change"
1708 * operation - just let it fallthrough..
1709 *
1710 * 1. We are allowed to create/graft only
1711 * if the request is explicitly stating
1712 * "please create if it doesn't exist".
1713 *
1714 * 2. If the request is to exclusive create
1715 * then the qdisc tcm_handle is not expected
1716 * to exist, so that we choose create/graft too.
1717 *
1718 * 3. The last case is when no flags are set.
1719 * This will happen when for example tc
1720 * utility issues a "change" command.
1721 * Alas, it is sort of hole in API, we
1722 * cannot decide what to do unambiguously.
1723 * For now we select create/graft.
1724 */
1725 if (tca[TCA_KIND] &&
1726 nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1727 if (req_create_or_replace(n) ||
1728 req_create_exclusive(n))
1729 goto create_n_graft;
1730 else if (req_change(n))
1731 goto create_n_graft2;
1732 }
1733 }
1734 }
1735 } else {
1736 if (!tcm->tcm_handle) {
1737 NL_SET_ERR_MSG(extack, "Handle cannot be zero");
1738 return -EINVAL;
1739 }
1740 q = qdisc_lookup(dev, tcm->tcm_handle);
1741 }
1742
1743 /* Change qdisc parameters */
1744 if (!q) {
1745 NL_SET_ERR_MSG(extack, "Specified qdisc not found");
1746 return -ENOENT;
1747 }
1748 if (n->nlmsg_flags & NLM_F_EXCL) {
1749 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify");
1750 return -EEXIST;
1751 }
1752 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1753 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1754 return -EINVAL;
1755 }
1756 err = qdisc_change(q, tca, extack);
1757 if (err == 0)
1758 qdisc_notify(net, skb, n, clid, NULL, q, extack);
1759 return err;
1760
1761create_n_graft:
1762 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
1763 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag");
1764 return -ENOENT;
1765 }
1766create_n_graft2:
1767 if (clid == TC_H_INGRESS) {
1768 if (dev_ingress_queue(dev)) {
1769 q = qdisc_create(dev, dev_ingress_queue(dev),
1770 tcm->tcm_parent, tcm->tcm_parent,
1771 tca, &err, extack);
1772 } else {
1773 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device");
1774 err = -ENOENT;
1775 }
1776 } else {
1777 struct netdev_queue *dev_queue;
1778
1779 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1780 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1781 else if (p)
1782 dev_queue = p->dev_queue;
1783 else
1784 dev_queue = netdev_get_tx_queue(dev, 0);
1785
1786 q = qdisc_create(dev, dev_queue,
1787 tcm->tcm_parent, tcm->tcm_handle,
1788 tca, &err, extack);
1789 }
1790 if (q == NULL) {
1791 if (err == -EAGAIN)
1792 goto replay;
1793 return err;
1794 }
1795
1796graft:
1797 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack);
1798 if (err) {
1799 if (q)
1800 qdisc_put(q);
1801 return err;
1802 }
1803
1804 return 0;
1805}
1806
1807static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1808 struct netlink_callback *cb,
1809 int *q_idx_p, int s_q_idx, bool recur,
1810 bool dump_invisible)
1811{
1812 int ret = 0, q_idx = *q_idx_p;
1813 struct Qdisc *q;
1814 int b;
1815
1816 if (!root)
1817 return 0;
1818
1819 q = root;
1820 if (q_idx < s_q_idx) {
1821 q_idx++;
1822 } else {
1823 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1824 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1825 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1826 RTM_NEWQDISC, NULL) <= 0)
1827 goto done;
1828 q_idx++;
1829 }
1830
1831 /* If dumping singletons, there is no qdisc_dev(root) and the singleton
1832 * itself has already been dumped.
1833 *
1834 * If we've already dumped the top-level (ingress) qdisc above and the global
1835 * qdisc hashtable, we don't want to hit it again
1836 */
1837 if (!qdisc_dev(root) || !recur)
1838 goto out;
1839
1840 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1841 if (q_idx < s_q_idx) {
1842 q_idx++;
1843 continue;
1844 }
1845 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1846 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1847 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1848 RTM_NEWQDISC, NULL) <= 0)
1849 goto done;
1850 q_idx++;
1851 }
1852
1853out:
1854 *q_idx_p = q_idx;
1855 return ret;
1856done:
1857 ret = -1;
1858 goto out;
1859}
1860
1861static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1862{
1863 struct net *net = sock_net(skb->sk);
1864 int idx, q_idx;
1865 int s_idx, s_q_idx;
1866 struct net_device *dev;
1867 const struct nlmsghdr *nlh = cb->nlh;
1868 struct nlattr *tca[TCA_MAX + 1];
1869 int err;
1870
1871 s_idx = cb->args[0];
1872 s_q_idx = q_idx = cb->args[1];
1873
1874 idx = 0;
1875 ASSERT_RTNL();
1876
1877 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX,
1878 rtm_tca_policy, cb->extack);
1879 if (err < 0)
1880 return err;
1881
1882 for_each_netdev(net, dev) {
1883 struct netdev_queue *dev_queue;
1884
1885 if (idx < s_idx)
1886 goto cont;
1887 if (idx > s_idx)
1888 s_q_idx = 0;
1889 q_idx = 0;
1890
1891 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc),
1892 skb, cb, &q_idx, s_q_idx,
1893 true, tca[TCA_DUMP_INVISIBLE]) < 0)
1894 goto done;
1895
1896 dev_queue = dev_ingress_queue(dev);
1897 if (dev_queue &&
1898 tc_dump_qdisc_root(rtnl_dereference(dev_queue->qdisc_sleeping),
1899 skb, cb, &q_idx, s_q_idx, false,
1900 tca[TCA_DUMP_INVISIBLE]) < 0)
1901 goto done;
1902
1903cont:
1904 idx++;
1905 }
1906
1907done:
1908 cb->args[0] = idx;
1909 cb->args[1] = q_idx;
1910
1911 return skb->len;
1912}
1913
1914
1915
1916/************************************************
1917 * Traffic classes manipulation. *
1918 ************************************************/
1919
1920static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1921 unsigned long cl, u32 portid, u32 seq, u16 flags,
1922 int event, struct netlink_ext_ack *extack)
1923{
1924 struct tcmsg *tcm;
1925 struct nlmsghdr *nlh;
1926 unsigned char *b = skb_tail_pointer(skb);
1927 struct gnet_dump d;
1928 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1929
1930 cond_resched();
1931 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1932 if (!nlh)
1933 goto out_nlmsg_trim;
1934 tcm = nlmsg_data(nlh);
1935 tcm->tcm_family = AF_UNSPEC;
1936 tcm->tcm__pad1 = 0;
1937 tcm->tcm__pad2 = 0;
1938 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1939 tcm->tcm_parent = q->handle;
1940 tcm->tcm_handle = q->handle;
1941 tcm->tcm_info = 0;
1942 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1943 goto nla_put_failure;
1944 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1945 goto nla_put_failure;
1946
1947 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1948 NULL, &d, TCA_PAD) < 0)
1949 goto nla_put_failure;
1950
1951 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1952 goto nla_put_failure;
1953
1954 if (gnet_stats_finish_copy(&d) < 0)
1955 goto nla_put_failure;
1956
1957 if (extack && extack->_msg &&
1958 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
1959 goto out_nlmsg_trim;
1960
1961 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1962
1963 return skb->len;
1964
1965out_nlmsg_trim:
1966nla_put_failure:
1967 nlmsg_trim(skb, b);
1968 return -1;
1969}
1970
1971static int tclass_notify(struct net *net, struct sk_buff *oskb,
1972 struct nlmsghdr *n, struct Qdisc *q,
1973 unsigned long cl, int event, struct netlink_ext_ack *extack)
1974{
1975 struct sk_buff *skb;
1976 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1977
1978 if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
1979 return 0;
1980
1981 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1982 if (!skb)
1983 return -ENOBUFS;
1984
1985 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event, extack) < 0) {
1986 kfree_skb(skb);
1987 return -EINVAL;
1988 }
1989
1990 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1991 n->nlmsg_flags & NLM_F_ECHO);
1992}
1993
1994static int tclass_get_notify(struct net *net, struct sk_buff *oskb,
1995 struct nlmsghdr *n, struct Qdisc *q,
1996 unsigned long cl, struct netlink_ext_ack *extack)
1997{
1998 struct sk_buff *skb;
1999 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2000
2001 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2002 if (!skb)
2003 return -ENOBUFS;
2004
2005 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, RTM_NEWTCLASS,
2006 extack) < 0) {
2007 kfree_skb(skb);
2008 return -EINVAL;
2009 }
2010
2011 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2012 n->nlmsg_flags & NLM_F_ECHO);
2013}
2014
2015static int tclass_del_notify(struct net *net,
2016 const struct Qdisc_class_ops *cops,
2017 struct sk_buff *oskb, struct nlmsghdr *n,
2018 struct Qdisc *q, unsigned long cl,
2019 struct netlink_ext_ack *extack)
2020{
2021 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2022 struct sk_buff *skb;
2023 int err = 0;
2024
2025 if (!cops->delete)
2026 return -EOPNOTSUPP;
2027
2028 if (rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2029 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2030 if (!skb)
2031 return -ENOBUFS;
2032
2033 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0,
2034 RTM_DELTCLASS, extack) < 0) {
2035 kfree_skb(skb);
2036 return -EINVAL;
2037 }
2038 } else {
2039 skb = NULL;
2040 }
2041
2042 err = cops->delete(q, cl, extack);
2043 if (err) {
2044 kfree_skb(skb);
2045 return err;
2046 }
2047
2048 err = rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2049 n->nlmsg_flags & NLM_F_ECHO);
2050 return err;
2051}
2052
2053#ifdef CONFIG_NET_CLS
2054
2055struct tcf_bind_args {
2056 struct tcf_walker w;
2057 unsigned long base;
2058 unsigned long cl;
2059 u32 classid;
2060};
2061
2062static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2063{
2064 struct tcf_bind_args *a = (void *)arg;
2065
2066 if (n && tp->ops->bind_class) {
2067 struct Qdisc *q = tcf_block_q(tp->chain->block);
2068
2069 sch_tree_lock(q);
2070 tp->ops->bind_class(n, a->classid, a->cl, q, a->base);
2071 sch_tree_unlock(q);
2072 }
2073 return 0;
2074}
2075
2076struct tc_bind_class_args {
2077 struct qdisc_walker w;
2078 unsigned long new_cl;
2079 u32 portid;
2080 u32 clid;
2081};
2082
2083static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl,
2084 struct qdisc_walker *w)
2085{
2086 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w;
2087 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
2088 struct tcf_block *block;
2089 struct tcf_chain *chain;
2090
2091 block = cops->tcf_block(q, cl, NULL);
2092 if (!block)
2093 return 0;
2094 for (chain = tcf_get_next_chain(block, NULL);
2095 chain;
2096 chain = tcf_get_next_chain(block, chain)) {
2097 struct tcf_proto *tp;
2098
2099 for (tp = tcf_get_next_proto(chain, NULL);
2100 tp; tp = tcf_get_next_proto(chain, tp)) {
2101 struct tcf_bind_args arg = {};
2102
2103 arg.w.fn = tcf_node_bind;
2104 arg.classid = a->clid;
2105 arg.base = cl;
2106 arg.cl = a->new_cl;
2107 tp->ops->walk(tp, &arg.w, true);
2108 }
2109 }
2110
2111 return 0;
2112}
2113
2114static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
2115 unsigned long new_cl)
2116{
2117 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
2118 struct tc_bind_class_args args = {};
2119
2120 if (!cops->tcf_block)
2121 return;
2122 args.portid = portid;
2123 args.clid = clid;
2124 args.new_cl = new_cl;
2125 args.w.fn = tc_bind_class_walker;
2126 q->ops->cl_ops->walk(q, &args.w);
2127}
2128
2129#else
2130
2131static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
2132 unsigned long new_cl)
2133{
2134}
2135
2136#endif
2137
2138static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n,
2139 struct netlink_ext_ack *extack)
2140{
2141 struct net *net = sock_net(skb->sk);
2142 struct tcmsg *tcm = nlmsg_data(n);
2143 struct nlattr *tca[TCA_MAX + 1];
2144 struct net_device *dev;
2145 struct Qdisc *q = NULL;
2146 const struct Qdisc_class_ops *cops;
2147 unsigned long cl = 0;
2148 unsigned long new_cl;
2149 u32 portid;
2150 u32 clid;
2151 u32 qid;
2152 int err;
2153
2154 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
2155 rtm_tca_policy, extack);
2156 if (err < 0)
2157 return err;
2158
2159 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2160 if (!dev)
2161 return -ENODEV;
2162
2163 /*
2164 parent == TC_H_UNSPEC - unspecified parent.
2165 parent == TC_H_ROOT - class is root, which has no parent.
2166 parent == X:0 - parent is root class.
2167 parent == X:Y - parent is a node in hierarchy.
2168 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
2169
2170 handle == 0:0 - generate handle from kernel pool.
2171 handle == 0:Y - class is X:Y, where X:0 is qdisc.
2172 handle == X:Y - clear.
2173 handle == X:0 - root class.
2174 */
2175
2176 /* Step 1. Determine qdisc handle X:0 */
2177
2178 portid = tcm->tcm_parent;
2179 clid = tcm->tcm_handle;
2180 qid = TC_H_MAJ(clid);
2181
2182 if (portid != TC_H_ROOT) {
2183 u32 qid1 = TC_H_MAJ(portid);
2184
2185 if (qid && qid1) {
2186 /* If both majors are known, they must be identical. */
2187 if (qid != qid1)
2188 return -EINVAL;
2189 } else if (qid1) {
2190 qid = qid1;
2191 } else if (qid == 0)
2192 qid = rtnl_dereference(dev->qdisc)->handle;
2193
2194 /* Now qid is genuine qdisc handle consistent
2195 * both with parent and child.
2196 *
2197 * TC_H_MAJ(portid) still may be unspecified, complete it now.
2198 */
2199 if (portid)
2200 portid = TC_H_MAKE(qid, portid);
2201 } else {
2202 if (qid == 0)
2203 qid = rtnl_dereference(dev->qdisc)->handle;
2204 }
2205
2206 /* OK. Locate qdisc */
2207 q = qdisc_lookup(dev, qid);
2208 if (!q)
2209 return -ENOENT;
2210
2211 /* An check that it supports classes */
2212 cops = q->ops->cl_ops;
2213 if (cops == NULL)
2214 return -EINVAL;
2215
2216 /* Now try to get class */
2217 if (clid == 0) {
2218 if (portid == TC_H_ROOT)
2219 clid = qid;
2220 } else
2221 clid = TC_H_MAKE(qid, clid);
2222
2223 if (clid)
2224 cl = cops->find(q, clid);
2225
2226 if (cl == 0) {
2227 err = -ENOENT;
2228 if (n->nlmsg_type != RTM_NEWTCLASS ||
2229 !(n->nlmsg_flags & NLM_F_CREATE))
2230 goto out;
2231 } else {
2232 switch (n->nlmsg_type) {
2233 case RTM_NEWTCLASS:
2234 err = -EEXIST;
2235 if (n->nlmsg_flags & NLM_F_EXCL)
2236 goto out;
2237 break;
2238 case RTM_DELTCLASS:
2239 err = tclass_del_notify(net, cops, skb, n, q, cl, extack);
2240 /* Unbind the class with flilters with 0 */
2241 tc_bind_tclass(q, portid, clid, 0);
2242 goto out;
2243 case RTM_GETTCLASS:
2244 err = tclass_get_notify(net, skb, n, q, cl, extack);
2245 goto out;
2246 default:
2247 err = -EINVAL;
2248 goto out;
2249 }
2250 }
2251
2252 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
2253 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes");
2254 return -EOPNOTSUPP;
2255 }
2256
2257 new_cl = cl;
2258 err = -EOPNOTSUPP;
2259 if (cops->change)
2260 err = cops->change(q, clid, portid, tca, &new_cl, extack);
2261 if (err == 0) {
2262 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack);
2263 /* We just create a new class, need to do reverse binding. */
2264 if (cl != new_cl)
2265 tc_bind_tclass(q, portid, clid, new_cl);
2266 }
2267out:
2268 return err;
2269}
2270
2271struct qdisc_dump_args {
2272 struct qdisc_walker w;
2273 struct sk_buff *skb;
2274 struct netlink_callback *cb;
2275};
2276
2277static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
2278 struct qdisc_walker *arg)
2279{
2280 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
2281
2282 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
2283 a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2284 RTM_NEWTCLASS, NULL);
2285}
2286
2287static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
2288 struct tcmsg *tcm, struct netlink_callback *cb,
2289 int *t_p, int s_t)
2290{
2291 struct qdisc_dump_args arg;
2292
2293 if (tc_qdisc_dump_ignore(q, false) ||
2294 *t_p < s_t || !q->ops->cl_ops ||
2295 (tcm->tcm_parent &&
2296 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
2297 (*t_p)++;
2298 return 0;
2299 }
2300 if (*t_p > s_t)
2301 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
2302 arg.w.fn = qdisc_class_dump;
2303 arg.skb = skb;
2304 arg.cb = cb;
2305 arg.w.stop = 0;
2306 arg.w.skip = cb->args[1];
2307 arg.w.count = 0;
2308 q->ops->cl_ops->walk(q, &arg.w);
2309 cb->args[1] = arg.w.count;
2310 if (arg.w.stop)
2311 return -1;
2312 (*t_p)++;
2313 return 0;
2314}
2315
2316static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
2317 struct tcmsg *tcm, struct netlink_callback *cb,
2318 int *t_p, int s_t, bool recur)
2319{
2320 struct Qdisc *q;
2321 int b;
2322
2323 if (!root)
2324 return 0;
2325
2326 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
2327 return -1;
2328
2329 if (!qdisc_dev(root) || !recur)
2330 return 0;
2331
2332 if (tcm->tcm_parent) {
2333 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
2334 if (q && q != root &&
2335 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2336 return -1;
2337 return 0;
2338 }
2339 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
2340 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2341 return -1;
2342 }
2343
2344 return 0;
2345}
2346
2347static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
2348{
2349 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2350 struct net *net = sock_net(skb->sk);
2351 struct netdev_queue *dev_queue;
2352 struct net_device *dev;
2353 int t, s_t;
2354
2355 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2356 return 0;
2357 dev = dev_get_by_index(net, tcm->tcm_ifindex);
2358 if (!dev)
2359 return 0;
2360
2361 s_t = cb->args[0];
2362 t = 0;
2363
2364 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc),
2365 skb, tcm, cb, &t, s_t, true) < 0)
2366 goto done;
2367
2368 dev_queue = dev_ingress_queue(dev);
2369 if (dev_queue &&
2370 tc_dump_tclass_root(rtnl_dereference(dev_queue->qdisc_sleeping),
2371 skb, tcm, cb, &t, s_t, false) < 0)
2372 goto done;
2373
2374done:
2375 cb->args[0] = t;
2376
2377 dev_put(dev);
2378 return skb->len;
2379}
2380
2381#ifdef CONFIG_PROC_FS
2382static int psched_show(struct seq_file *seq, void *v)
2383{
2384 seq_printf(seq, "%08x %08x %08x %08x\n",
2385 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
2386 1000000,
2387 (u32)NSEC_PER_SEC / hrtimer_resolution);
2388
2389 return 0;
2390}
2391
2392static int __net_init psched_net_init(struct net *net)
2393{
2394 struct proc_dir_entry *e;
2395
2396 e = proc_create_single("psched", 0, net->proc_net, psched_show);
2397 if (e == NULL)
2398 return -ENOMEM;
2399
2400 return 0;
2401}
2402
2403static void __net_exit psched_net_exit(struct net *net)
2404{
2405 remove_proc_entry("psched", net->proc_net);
2406}
2407#else
2408static int __net_init psched_net_init(struct net *net)
2409{
2410 return 0;
2411}
2412
2413static void __net_exit psched_net_exit(struct net *net)
2414{
2415}
2416#endif
2417
2418static struct pernet_operations psched_net_ops = {
2419 .init = psched_net_init,
2420 .exit = psched_net_exit,
2421};
2422
2423#if IS_ENABLED(CONFIG_MITIGATION_RETPOLINE)
2424DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper);
2425#endif
2426
2427static const struct rtnl_msg_handler psched_rtnl_msg_handlers[] __initconst = {
2428 {.msgtype = RTM_NEWQDISC, .doit = tc_modify_qdisc},
2429 {.msgtype = RTM_DELQDISC, .doit = tc_get_qdisc},
2430 {.msgtype = RTM_GETQDISC, .doit = tc_get_qdisc,
2431 .dumpit = tc_dump_qdisc},
2432 {.msgtype = RTM_NEWTCLASS, .doit = tc_ctl_tclass},
2433 {.msgtype = RTM_DELTCLASS, .doit = tc_ctl_tclass},
2434 {.msgtype = RTM_GETTCLASS, .doit = tc_ctl_tclass,
2435 .dumpit = tc_dump_tclass},
2436};
2437
2438static int __init pktsched_init(void)
2439{
2440 int err;
2441
2442 err = register_pernet_subsys(&psched_net_ops);
2443 if (err) {
2444 pr_err("pktsched_init: "
2445 "cannot initialize per netns operations\n");
2446 return err;
2447 }
2448
2449 register_qdisc(&pfifo_fast_ops);
2450 register_qdisc(&pfifo_qdisc_ops);
2451 register_qdisc(&bfifo_qdisc_ops);
2452 register_qdisc(&pfifo_head_drop_qdisc_ops);
2453 register_qdisc(&mq_qdisc_ops);
2454 register_qdisc(&noqueue_qdisc_ops);
2455
2456 rtnl_register_many(psched_rtnl_msg_handlers);
2457
2458 tc_wrapper_init();
2459
2460 return 0;
2461}
2462
2463subsys_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
35#include <trace/events/qdisc.h>
36
37/*
38
39 Short review.
40 -------------
41
42 This file consists of two interrelated parts:
43
44 1. queueing disciplines manager frontend.
45 2. traffic classes manager frontend.
46
47 Generally, queueing discipline ("qdisc") is a black box,
48 which is able to enqueue packets and to dequeue them (when
49 device is ready to send something) in order and at times
50 determined by algorithm hidden in it.
51
52 qdisc's are divided to two categories:
53 - "queues", which have no internal structure visible from outside.
54 - "schedulers", which split all the packets to "traffic classes",
55 using "packet classifiers" (look at cls_api.c)
56
57 In turn, classes may have child qdiscs (as rule, queues)
58 attached to them etc. etc. etc.
59
60 The goal of the routines in this file is to translate
61 information supplied by user in the form of handles
62 to more intelligible for kernel form, to make some sanity
63 checks and part of work, which is common to all qdiscs
64 and to provide rtnetlink notifications.
65
66 All real intelligent work is done inside qdisc modules.
67
68
69
70 Every discipline has two major routines: enqueue and dequeue.
71
72 ---dequeue
73
74 dequeue usually returns a skb to send. It is allowed to return NULL,
75 but it does not mean that queue is empty, it just means that
76 discipline does not want to send anything this time.
77 Queue is really empty if q->q.qlen == 0.
78 For complicated disciplines with multiple queues q->q is not
79 real packet queue, but however q->q.qlen must be valid.
80
81 ---enqueue
82
83 enqueue returns 0, if packet was enqueued successfully.
84 If packet (this one or another one) was dropped, it returns
85 not zero error code.
86 NET_XMIT_DROP - this packet dropped
87 Expected action: do not backoff, but wait until queue will clear.
88 NET_XMIT_CN - probably this packet enqueued, but another one dropped.
89 Expected action: backoff or ignore
90
91 Auxiliary routines:
92
93 ---peek
94
95 like dequeue but without removing a packet from the queue
96
97 ---reset
98
99 returns qdisc to initial state: purge all buffers, clear all
100 timers, counters (except for statistics) etc.
101
102 ---init
103
104 initializes newly created qdisc.
105
106 ---destroy
107
108 destroys resources allocated by init and during lifetime of qdisc.
109
110 ---change
111
112 changes qdisc parameters.
113 */
114
115/* Protects list of registered TC modules. It is pure SMP lock. */
116static DEFINE_RWLOCK(qdisc_mod_lock);
117
118
119/************************************************
120 * Queueing disciplines manipulation. *
121 ************************************************/
122
123
124/* The list of all installed queueing disciplines. */
125
126static struct Qdisc_ops *qdisc_base;
127
128/* Register/unregister queueing discipline */
129
130int register_qdisc(struct Qdisc_ops *qops)
131{
132 struct Qdisc_ops *q, **qp;
133 int rc = -EEXIST;
134
135 write_lock(&qdisc_mod_lock);
136 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
137 if (!strcmp(qops->id, q->id))
138 goto out;
139
140 if (qops->enqueue == NULL)
141 qops->enqueue = noop_qdisc_ops.enqueue;
142 if (qops->peek == NULL) {
143 if (qops->dequeue == NULL)
144 qops->peek = noop_qdisc_ops.peek;
145 else
146 goto out_einval;
147 }
148 if (qops->dequeue == NULL)
149 qops->dequeue = noop_qdisc_ops.dequeue;
150
151 if (qops->cl_ops) {
152 const struct Qdisc_class_ops *cops = qops->cl_ops;
153
154 if (!(cops->find && cops->walk && cops->leaf))
155 goto out_einval;
156
157 if (cops->tcf_block && !(cops->bind_tcf && cops->unbind_tcf))
158 goto out_einval;
159 }
160
161 qops->next = NULL;
162 *qp = qops;
163 rc = 0;
164out:
165 write_unlock(&qdisc_mod_lock);
166 return rc;
167
168out_einval:
169 rc = -EINVAL;
170 goto out;
171}
172EXPORT_SYMBOL(register_qdisc);
173
174int unregister_qdisc(struct Qdisc_ops *qops)
175{
176 struct Qdisc_ops *q, **qp;
177 int err = -ENOENT;
178
179 write_lock(&qdisc_mod_lock);
180 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
181 if (q == qops)
182 break;
183 if (q) {
184 *qp = q->next;
185 q->next = NULL;
186 err = 0;
187 }
188 write_unlock(&qdisc_mod_lock);
189 return err;
190}
191EXPORT_SYMBOL(unregister_qdisc);
192
193/* Get default qdisc if not otherwise specified */
194void qdisc_get_default(char *name, size_t len)
195{
196 read_lock(&qdisc_mod_lock);
197 strlcpy(name, default_qdisc_ops->id, len);
198 read_unlock(&qdisc_mod_lock);
199}
200
201static struct Qdisc_ops *qdisc_lookup_default(const char *name)
202{
203 struct Qdisc_ops *q = NULL;
204
205 for (q = qdisc_base; q; q = q->next) {
206 if (!strcmp(name, q->id)) {
207 if (!try_module_get(q->owner))
208 q = NULL;
209 break;
210 }
211 }
212
213 return q;
214}
215
216/* Set new default qdisc to use */
217int qdisc_set_default(const char *name)
218{
219 const struct Qdisc_ops *ops;
220
221 if (!capable(CAP_NET_ADMIN))
222 return -EPERM;
223
224 write_lock(&qdisc_mod_lock);
225 ops = qdisc_lookup_default(name);
226 if (!ops) {
227 /* Not found, drop lock and try to load module */
228 write_unlock(&qdisc_mod_lock);
229 request_module("sch_%s", name);
230 write_lock(&qdisc_mod_lock);
231
232 ops = qdisc_lookup_default(name);
233 }
234
235 if (ops) {
236 /* Set new default */
237 module_put(default_qdisc_ops->owner);
238 default_qdisc_ops = ops;
239 }
240 write_unlock(&qdisc_mod_lock);
241
242 return ops ? 0 : -ENOENT;
243}
244
245#ifdef CONFIG_NET_SCH_DEFAULT
246/* Set default value from kernel config */
247static int __init sch_default_qdisc(void)
248{
249 return qdisc_set_default(CONFIG_DEFAULT_NET_SCH);
250}
251late_initcall(sch_default_qdisc);
252#endif
253
254/* We know handle. Find qdisc among all qdisc's attached to device
255 * (root qdisc, all its children, children of children etc.)
256 * Note: caller either uses rtnl or rcu_read_lock()
257 */
258
259static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
260{
261 struct Qdisc *q;
262
263 if (!qdisc_dev(root))
264 return (root->handle == handle ? root : NULL);
265
266 if (!(root->flags & TCQ_F_BUILTIN) &&
267 root->handle == handle)
268 return root;
269
270 hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle,
271 lockdep_rtnl_is_held()) {
272 if (q->handle == handle)
273 return q;
274 }
275 return NULL;
276}
277
278void qdisc_hash_add(struct Qdisc *q, bool invisible)
279{
280 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
281 ASSERT_RTNL();
282 hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle);
283 if (invisible)
284 q->flags |= TCQ_F_INVISIBLE;
285 }
286}
287EXPORT_SYMBOL(qdisc_hash_add);
288
289void qdisc_hash_del(struct Qdisc *q)
290{
291 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) {
292 ASSERT_RTNL();
293 hash_del_rcu(&q->hash);
294 }
295}
296EXPORT_SYMBOL(qdisc_hash_del);
297
298struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
299{
300 struct Qdisc *q;
301
302 if (!handle)
303 return NULL;
304 q = qdisc_match_from_root(dev->qdisc, handle);
305 if (q)
306 goto out;
307
308 if (dev_ingress_queue(dev))
309 q = qdisc_match_from_root(
310 dev_ingress_queue(dev)->qdisc_sleeping,
311 handle);
312out:
313 return q;
314}
315
316struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle)
317{
318 struct netdev_queue *nq;
319 struct Qdisc *q;
320
321 if (!handle)
322 return NULL;
323 q = qdisc_match_from_root(dev->qdisc, handle);
324 if (q)
325 goto out;
326
327 nq = dev_ingress_queue_rcu(dev);
328 if (nq)
329 q = qdisc_match_from_root(nq->qdisc_sleeping, handle);
330out:
331 return q;
332}
333
334static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
335{
336 unsigned long cl;
337 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
338
339 if (cops == NULL)
340 return NULL;
341 cl = cops->find(p, classid);
342
343 if (cl == 0)
344 return NULL;
345 return cops->leaf(p, cl);
346}
347
348/* Find queueing discipline by name */
349
350static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
351{
352 struct Qdisc_ops *q = NULL;
353
354 if (kind) {
355 read_lock(&qdisc_mod_lock);
356 for (q = qdisc_base; q; q = q->next) {
357 if (nla_strcmp(kind, q->id) == 0) {
358 if (!try_module_get(q->owner))
359 q = NULL;
360 break;
361 }
362 }
363 read_unlock(&qdisc_mod_lock);
364 }
365 return q;
366}
367
368/* The linklayer setting were not transferred from iproute2, in older
369 * versions, and the rate tables lookup systems have been dropped in
370 * the kernel. To keep backward compatible with older iproute2 tc
371 * utils, we detect the linklayer setting by detecting if the rate
372 * table were modified.
373 *
374 * For linklayer ATM table entries, the rate table will be aligned to
375 * 48 bytes, thus some table entries will contain the same value. The
376 * mpu (min packet unit) is also encoded into the old rate table, thus
377 * starting from the mpu, we find low and high table entries for
378 * mapping this cell. If these entries contain the same value, when
379 * the rate tables have been modified for linklayer ATM.
380 *
381 * This is done by rounding mpu to the nearest 48 bytes cell/entry,
382 * and then roundup to the next cell, calc the table entry one below,
383 * and compare.
384 */
385static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab)
386{
387 int low = roundup(r->mpu, 48);
388 int high = roundup(low+1, 48);
389 int cell_low = low >> r->cell_log;
390 int cell_high = (high >> r->cell_log) - 1;
391
392 /* rtab is too inaccurate at rates > 100Mbit/s */
393 if ((r->rate > (100000000/8)) || (rtab[0] == 0)) {
394 pr_debug("TC linklayer: Giving up ATM detection\n");
395 return TC_LINKLAYER_ETHERNET;
396 }
397
398 if ((cell_high > cell_low) && (cell_high < 256)
399 && (rtab[cell_low] == rtab[cell_high])) {
400 pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n",
401 cell_low, cell_high, rtab[cell_high]);
402 return TC_LINKLAYER_ATM;
403 }
404 return TC_LINKLAYER_ETHERNET;
405}
406
407static struct qdisc_rate_table *qdisc_rtab_list;
408
409struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r,
410 struct nlattr *tab,
411 struct netlink_ext_ack *extack)
412{
413 struct qdisc_rate_table *rtab;
414
415 if (tab == NULL || r->rate == 0 ||
416 r->cell_log == 0 || r->cell_log >= 32 ||
417 nla_len(tab) != TC_RTAB_SIZE) {
418 NL_SET_ERR_MSG(extack, "Invalid rate table parameters for searching");
419 return NULL;
420 }
421
422 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
423 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) &&
424 !memcmp(&rtab->data, nla_data(tab), 1024)) {
425 rtab->refcnt++;
426 return rtab;
427 }
428 }
429
430 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
431 if (rtab) {
432 rtab->rate = *r;
433 rtab->refcnt = 1;
434 memcpy(rtab->data, nla_data(tab), 1024);
435 if (r->linklayer == TC_LINKLAYER_UNAWARE)
436 r->linklayer = __detect_linklayer(r, rtab->data);
437 rtab->next = qdisc_rtab_list;
438 qdisc_rtab_list = rtab;
439 } else {
440 NL_SET_ERR_MSG(extack, "Failed to allocate new qdisc rate table");
441 }
442 return rtab;
443}
444EXPORT_SYMBOL(qdisc_get_rtab);
445
446void qdisc_put_rtab(struct qdisc_rate_table *tab)
447{
448 struct qdisc_rate_table *rtab, **rtabp;
449
450 if (!tab || --tab->refcnt)
451 return;
452
453 for (rtabp = &qdisc_rtab_list;
454 (rtab = *rtabp) != NULL;
455 rtabp = &rtab->next) {
456 if (rtab == tab) {
457 *rtabp = rtab->next;
458 kfree(rtab);
459 return;
460 }
461 }
462}
463EXPORT_SYMBOL(qdisc_put_rtab);
464
465static LIST_HEAD(qdisc_stab_list);
466
467static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
468 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) },
469 [TCA_STAB_DATA] = { .type = NLA_BINARY },
470};
471
472static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt,
473 struct netlink_ext_ack *extack)
474{
475 struct nlattr *tb[TCA_STAB_MAX + 1];
476 struct qdisc_size_table *stab;
477 struct tc_sizespec *s;
478 unsigned int tsize = 0;
479 u16 *tab = NULL;
480 int err;
481
482 err = nla_parse_nested_deprecated(tb, TCA_STAB_MAX, opt, stab_policy,
483 extack);
484 if (err < 0)
485 return ERR_PTR(err);
486 if (!tb[TCA_STAB_BASE]) {
487 NL_SET_ERR_MSG(extack, "Size table base attribute is missing");
488 return ERR_PTR(-EINVAL);
489 }
490
491 s = nla_data(tb[TCA_STAB_BASE]);
492
493 if (s->tsize > 0) {
494 if (!tb[TCA_STAB_DATA]) {
495 NL_SET_ERR_MSG(extack, "Size table data attribute is missing");
496 return ERR_PTR(-EINVAL);
497 }
498 tab = nla_data(tb[TCA_STAB_DATA]);
499 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
500 }
501
502 if (tsize != s->tsize || (!tab && tsize > 0)) {
503 NL_SET_ERR_MSG(extack, "Invalid size of size table");
504 return ERR_PTR(-EINVAL);
505 }
506
507 list_for_each_entry(stab, &qdisc_stab_list, list) {
508 if (memcmp(&stab->szopts, s, sizeof(*s)))
509 continue;
510 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16)))
511 continue;
512 stab->refcnt++;
513 return stab;
514 }
515
516 if (s->size_log > STAB_SIZE_LOG_MAX ||
517 s->cell_log > STAB_SIZE_LOG_MAX) {
518 NL_SET_ERR_MSG(extack, "Invalid logarithmic size of size table");
519 return ERR_PTR(-EINVAL);
520 }
521
522 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
523 if (!stab)
524 return ERR_PTR(-ENOMEM);
525
526 stab->refcnt = 1;
527 stab->szopts = *s;
528 if (tsize > 0)
529 memcpy(stab->data, tab, tsize * sizeof(u16));
530
531 list_add_tail(&stab->list, &qdisc_stab_list);
532
533 return stab;
534}
535
536void qdisc_put_stab(struct qdisc_size_table *tab)
537{
538 if (!tab)
539 return;
540
541 if (--tab->refcnt == 0) {
542 list_del(&tab->list);
543 kfree_rcu(tab, rcu);
544 }
545}
546EXPORT_SYMBOL(qdisc_put_stab);
547
548static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
549{
550 struct nlattr *nest;
551
552 nest = nla_nest_start_noflag(skb, TCA_STAB);
553 if (nest == NULL)
554 goto nla_put_failure;
555 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts))
556 goto nla_put_failure;
557 nla_nest_end(skb, nest);
558
559 return skb->len;
560
561nla_put_failure:
562 return -1;
563}
564
565void __qdisc_calculate_pkt_len(struct sk_buff *skb,
566 const struct qdisc_size_table *stab)
567{
568 int pkt_len, slot;
569
570 pkt_len = skb->len + stab->szopts.overhead;
571 if (unlikely(!stab->szopts.tsize))
572 goto out;
573
574 slot = pkt_len + stab->szopts.cell_align;
575 if (unlikely(slot < 0))
576 slot = 0;
577
578 slot >>= stab->szopts.cell_log;
579 if (likely(slot < stab->szopts.tsize))
580 pkt_len = stab->data[slot];
581 else
582 pkt_len = stab->data[stab->szopts.tsize - 1] *
583 (slot / stab->szopts.tsize) +
584 stab->data[slot % stab->szopts.tsize];
585
586 pkt_len <<= stab->szopts.size_log;
587out:
588 if (unlikely(pkt_len < 1))
589 pkt_len = 1;
590 qdisc_skb_cb(skb)->pkt_len = pkt_len;
591}
592EXPORT_SYMBOL(__qdisc_calculate_pkt_len);
593
594void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc)
595{
596 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
597 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n",
598 txt, qdisc->ops->id, qdisc->handle >> 16);
599 qdisc->flags |= TCQ_F_WARN_NONWC;
600 }
601}
602EXPORT_SYMBOL(qdisc_warn_nonwc);
603
604static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
605{
606 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
607 timer);
608
609 rcu_read_lock();
610 __netif_schedule(qdisc_root(wd->qdisc));
611 rcu_read_unlock();
612
613 return HRTIMER_NORESTART;
614}
615
616void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc,
617 clockid_t clockid)
618{
619 hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED);
620 wd->timer.function = qdisc_watchdog;
621 wd->qdisc = qdisc;
622}
623EXPORT_SYMBOL(qdisc_watchdog_init_clockid);
624
625void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
626{
627 qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC);
628}
629EXPORT_SYMBOL(qdisc_watchdog_init);
630
631void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
632 u64 delta_ns)
633{
634 if (test_bit(__QDISC_STATE_DEACTIVATED,
635 &qdisc_root_sleeping(wd->qdisc)->state))
636 return;
637
638 if (hrtimer_is_queued(&wd->timer)) {
639 /* If timer is already set in [expires, expires + delta_ns],
640 * do not reprogram it.
641 */
642 if (wd->last_expires - expires <= delta_ns)
643 return;
644 }
645
646 wd->last_expires = expires;
647 hrtimer_start_range_ns(&wd->timer,
648 ns_to_ktime(expires),
649 delta_ns,
650 HRTIMER_MODE_ABS_PINNED);
651}
652EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns);
653
654void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
655{
656 hrtimer_cancel(&wd->timer);
657}
658EXPORT_SYMBOL(qdisc_watchdog_cancel);
659
660static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
661{
662 struct hlist_head *h;
663 unsigned int i;
664
665 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL);
666
667 if (h != NULL) {
668 for (i = 0; i < n; i++)
669 INIT_HLIST_HEAD(&h[i]);
670 }
671 return h;
672}
673
674void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
675{
676 struct Qdisc_class_common *cl;
677 struct hlist_node *next;
678 struct hlist_head *nhash, *ohash;
679 unsigned int nsize, nmask, osize;
680 unsigned int i, h;
681
682 /* Rehash when load factor exceeds 0.75 */
683 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
684 return;
685 nsize = clhash->hashsize * 2;
686 nmask = nsize - 1;
687 nhash = qdisc_class_hash_alloc(nsize);
688 if (nhash == NULL)
689 return;
690
691 ohash = clhash->hash;
692 osize = clhash->hashsize;
693
694 sch_tree_lock(sch);
695 for (i = 0; i < osize; i++) {
696 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) {
697 h = qdisc_class_hash(cl->classid, nmask);
698 hlist_add_head(&cl->hnode, &nhash[h]);
699 }
700 }
701 clhash->hash = nhash;
702 clhash->hashsize = nsize;
703 clhash->hashmask = nmask;
704 sch_tree_unlock(sch);
705
706 kvfree(ohash);
707}
708EXPORT_SYMBOL(qdisc_class_hash_grow);
709
710int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
711{
712 unsigned int size = 4;
713
714 clhash->hash = qdisc_class_hash_alloc(size);
715 if (!clhash->hash)
716 return -ENOMEM;
717 clhash->hashsize = size;
718 clhash->hashmask = size - 1;
719 clhash->hashelems = 0;
720 return 0;
721}
722EXPORT_SYMBOL(qdisc_class_hash_init);
723
724void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
725{
726 kvfree(clhash->hash);
727}
728EXPORT_SYMBOL(qdisc_class_hash_destroy);
729
730void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
731 struct Qdisc_class_common *cl)
732{
733 unsigned int h;
734
735 INIT_HLIST_NODE(&cl->hnode);
736 h = qdisc_class_hash(cl->classid, clhash->hashmask);
737 hlist_add_head(&cl->hnode, &clhash->hash[h]);
738 clhash->hashelems++;
739}
740EXPORT_SYMBOL(qdisc_class_hash_insert);
741
742void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
743 struct Qdisc_class_common *cl)
744{
745 hlist_del(&cl->hnode);
746 clhash->hashelems--;
747}
748EXPORT_SYMBOL(qdisc_class_hash_remove);
749
750/* Allocate an unique handle from space managed by kernel
751 * Possible range is [8000-FFFF]:0000 (0x8000 values)
752 */
753static u32 qdisc_alloc_handle(struct net_device *dev)
754{
755 int i = 0x8000;
756 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
757
758 do {
759 autohandle += TC_H_MAKE(0x10000U, 0);
760 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
761 autohandle = TC_H_MAKE(0x80000000U, 0);
762 if (!qdisc_lookup(dev, autohandle))
763 return autohandle;
764 cond_resched();
765 } while (--i > 0);
766
767 return 0;
768}
769
770void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len)
771{
772 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED;
773 const struct Qdisc_class_ops *cops;
774 unsigned long cl;
775 u32 parentid;
776 bool notify;
777 int drops;
778
779 if (n == 0 && len == 0)
780 return;
781 drops = max_t(int, n, 0);
782 rcu_read_lock();
783 while ((parentid = sch->parent)) {
784 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
785 break;
786
787 if (sch->flags & TCQ_F_NOPARENT)
788 break;
789 /* Notify parent qdisc only if child qdisc becomes empty.
790 *
791 * If child was empty even before update then backlog
792 * counter is screwed and we skip notification because
793 * parent class is already passive.
794 *
795 * If the original child was offloaded then it is allowed
796 * to be seem as empty, so the parent is notified anyway.
797 */
798 notify = !sch->q.qlen && !WARN_ON_ONCE(!n &&
799 !qdisc_is_offloaded);
800 /* TODO: perform the search on a per txq basis */
801 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
802 if (sch == NULL) {
803 WARN_ON_ONCE(parentid != TC_H_ROOT);
804 break;
805 }
806 cops = sch->ops->cl_ops;
807 if (notify && cops->qlen_notify) {
808 cl = cops->find(sch, parentid);
809 cops->qlen_notify(sch, cl);
810 }
811 sch->q.qlen -= n;
812 sch->qstats.backlog -= len;
813 __qdisc_qstats_drop(sch, drops);
814 }
815 rcu_read_unlock();
816}
817EXPORT_SYMBOL(qdisc_tree_reduce_backlog);
818
819int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type,
820 void *type_data)
821{
822 struct net_device *dev = qdisc_dev(sch);
823 int err;
824
825 sch->flags &= ~TCQ_F_OFFLOADED;
826 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
827 return 0;
828
829 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
830 if (err == -EOPNOTSUPP)
831 return 0;
832
833 if (!err)
834 sch->flags |= TCQ_F_OFFLOADED;
835
836 return err;
837}
838EXPORT_SYMBOL(qdisc_offload_dump_helper);
839
840void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
841 struct Qdisc *new, struct Qdisc *old,
842 enum tc_setup_type type, void *type_data,
843 struct netlink_ext_ack *extack)
844{
845 bool any_qdisc_is_offloaded;
846 int err;
847
848 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc)
849 return;
850
851 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data);
852
853 /* Don't report error if the graft is part of destroy operation. */
854 if (!err || !new || new == &noop_qdisc)
855 return;
856
857 /* Don't report error if the parent, the old child and the new
858 * one are not offloaded.
859 */
860 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED;
861 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED;
862 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED;
863
864 if (any_qdisc_is_offloaded)
865 NL_SET_ERR_MSG(extack, "Offloading graft operation failed.");
866}
867EXPORT_SYMBOL(qdisc_offload_graft_helper);
868
869static void qdisc_offload_graft_root(struct net_device *dev,
870 struct Qdisc *new, struct Qdisc *old,
871 struct netlink_ext_ack *extack)
872{
873 struct tc_root_qopt_offload graft_offload = {
874 .command = TC_ROOT_GRAFT,
875 .handle = new ? new->handle : 0,
876 .ingress = (new && new->flags & TCQ_F_INGRESS) ||
877 (old && old->flags & TCQ_F_INGRESS),
878 };
879
880 qdisc_offload_graft_helper(dev, NULL, new, old,
881 TC_SETUP_ROOT_QDISC, &graft_offload, extack);
882}
883
884static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
885 u32 portid, u32 seq, u16 flags, int event)
886{
887 struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
888 struct gnet_stats_queue __percpu *cpu_qstats = NULL;
889 struct tcmsg *tcm;
890 struct nlmsghdr *nlh;
891 unsigned char *b = skb_tail_pointer(skb);
892 struct gnet_dump d;
893 struct qdisc_size_table *stab;
894 u32 block_index;
895 __u32 qlen;
896
897 cond_resched();
898 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
899 if (!nlh)
900 goto out_nlmsg_trim;
901 tcm = nlmsg_data(nlh);
902 tcm->tcm_family = AF_UNSPEC;
903 tcm->tcm__pad1 = 0;
904 tcm->tcm__pad2 = 0;
905 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
906 tcm->tcm_parent = clid;
907 tcm->tcm_handle = q->handle;
908 tcm->tcm_info = refcount_read(&q->refcnt);
909 if (nla_put_string(skb, TCA_KIND, q->ops->id))
910 goto nla_put_failure;
911 if (q->ops->ingress_block_get) {
912 block_index = q->ops->ingress_block_get(q);
913 if (block_index &&
914 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index))
915 goto nla_put_failure;
916 }
917 if (q->ops->egress_block_get) {
918 block_index = q->ops->egress_block_get(q);
919 if (block_index &&
920 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index))
921 goto nla_put_failure;
922 }
923 if (q->ops->dump && q->ops->dump(q, skb) < 0)
924 goto nla_put_failure;
925 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED)))
926 goto nla_put_failure;
927 qlen = qdisc_qlen_sum(q);
928
929 stab = rtnl_dereference(q->stab);
930 if (stab && qdisc_dump_stab(skb, stab) < 0)
931 goto nla_put_failure;
932
933 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
934 NULL, &d, TCA_PAD) < 0)
935 goto nla_put_failure;
936
937 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
938 goto nla_put_failure;
939
940 if (qdisc_is_percpu_stats(q)) {
941 cpu_bstats = q->cpu_bstats;
942 cpu_qstats = q->cpu_qstats;
943 }
944
945 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(q),
946 &d, cpu_bstats, &q->bstats) < 0 ||
947 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
948 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0)
949 goto nla_put_failure;
950
951 if (gnet_stats_finish_copy(&d) < 0)
952 goto nla_put_failure;
953
954 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
955 return skb->len;
956
957out_nlmsg_trim:
958nla_put_failure:
959 nlmsg_trim(skb, b);
960 return -1;
961}
962
963static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible)
964{
965 if (q->flags & TCQ_F_BUILTIN)
966 return true;
967 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible)
968 return true;
969
970 return false;
971}
972
973static int qdisc_notify(struct net *net, struct sk_buff *oskb,
974 struct nlmsghdr *n, u32 clid,
975 struct Qdisc *old, struct Qdisc *new)
976{
977 struct sk_buff *skb;
978 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
979
980 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
981 if (!skb)
982 return -ENOBUFS;
983
984 if (old && !tc_qdisc_dump_ignore(old, false)) {
985 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq,
986 0, RTM_DELQDISC) < 0)
987 goto err_out;
988 }
989 if (new && !tc_qdisc_dump_ignore(new, false)) {
990 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq,
991 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
992 goto err_out;
993 }
994
995 if (skb->len)
996 return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
997 n->nlmsg_flags & NLM_F_ECHO);
998
999err_out:
1000 kfree_skb(skb);
1001 return -EINVAL;
1002}
1003
1004static void notify_and_destroy(struct net *net, struct sk_buff *skb,
1005 struct nlmsghdr *n, u32 clid,
1006 struct Qdisc *old, struct Qdisc *new)
1007{
1008 if (new || old)
1009 qdisc_notify(net, skb, n, clid, old, new);
1010
1011 if (old)
1012 qdisc_put(old);
1013}
1014
1015static void qdisc_clear_nolock(struct Qdisc *sch)
1016{
1017 sch->flags &= ~TCQ_F_NOLOCK;
1018 if (!(sch->flags & TCQ_F_CPUSTATS))
1019 return;
1020
1021 free_percpu(sch->cpu_bstats);
1022 free_percpu(sch->cpu_qstats);
1023 sch->cpu_bstats = NULL;
1024 sch->cpu_qstats = NULL;
1025 sch->flags &= ~TCQ_F_CPUSTATS;
1026}
1027
1028/* Graft qdisc "new" to class "classid" of qdisc "parent" or
1029 * to device "dev".
1030 *
1031 * When appropriate send a netlink notification using 'skb'
1032 * and "n".
1033 *
1034 * On success, destroy old qdisc.
1035 */
1036
1037static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
1038 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
1039 struct Qdisc *new, struct Qdisc *old,
1040 struct netlink_ext_ack *extack)
1041{
1042 struct Qdisc *q = old;
1043 struct net *net = dev_net(dev);
1044
1045 if (parent == NULL) {
1046 unsigned int i, num_q, ingress;
1047
1048 ingress = 0;
1049 num_q = dev->num_tx_queues;
1050 if ((q && q->flags & TCQ_F_INGRESS) ||
1051 (new && new->flags & TCQ_F_INGRESS)) {
1052 num_q = 1;
1053 ingress = 1;
1054 if (!dev_ingress_queue(dev)) {
1055 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue");
1056 return -ENOENT;
1057 }
1058 }
1059
1060 if (dev->flags & IFF_UP)
1061 dev_deactivate(dev);
1062
1063 qdisc_offload_graft_root(dev, new, old, extack);
1064
1065 if (new && new->ops->attach)
1066 goto skip;
1067
1068 for (i = 0; i < num_q; i++) {
1069 struct netdev_queue *dev_queue = dev_ingress_queue(dev);
1070
1071 if (!ingress)
1072 dev_queue = netdev_get_tx_queue(dev, i);
1073
1074 old = dev_graft_qdisc(dev_queue, new);
1075 if (new && i > 0)
1076 qdisc_refcount_inc(new);
1077
1078 if (!ingress)
1079 qdisc_put(old);
1080 }
1081
1082skip:
1083 if (!ingress) {
1084 notify_and_destroy(net, skb, n, classid,
1085 dev->qdisc, new);
1086 if (new && !new->ops->attach)
1087 qdisc_refcount_inc(new);
1088 dev->qdisc = new ? : &noop_qdisc;
1089
1090 if (new && new->ops->attach)
1091 new->ops->attach(new);
1092 } else {
1093 notify_and_destroy(net, skb, n, classid, old, new);
1094 }
1095
1096 if (dev->flags & IFF_UP)
1097 dev_activate(dev);
1098 } else {
1099 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
1100 unsigned long cl;
1101 int err;
1102
1103 /* Only support running class lockless if parent is lockless */
1104 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK))
1105 qdisc_clear_nolock(new);
1106
1107 if (!cops || !cops->graft)
1108 return -EOPNOTSUPP;
1109
1110 cl = cops->find(parent, classid);
1111 if (!cl) {
1112 NL_SET_ERR_MSG(extack, "Specified class not found");
1113 return -ENOENT;
1114 }
1115
1116 err = cops->graft(parent, cl, new, &old, extack);
1117 if (err)
1118 return err;
1119 notify_and_destroy(net, skb, n, classid, old, new);
1120 }
1121 return 0;
1122}
1123
1124static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca,
1125 struct netlink_ext_ack *extack)
1126{
1127 u32 block_index;
1128
1129 if (tca[TCA_INGRESS_BLOCK]) {
1130 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]);
1131
1132 if (!block_index) {
1133 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0");
1134 return -EINVAL;
1135 }
1136 if (!sch->ops->ingress_block_set) {
1137 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported");
1138 return -EOPNOTSUPP;
1139 }
1140 sch->ops->ingress_block_set(sch, block_index);
1141 }
1142 if (tca[TCA_EGRESS_BLOCK]) {
1143 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]);
1144
1145 if (!block_index) {
1146 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0");
1147 return -EINVAL;
1148 }
1149 if (!sch->ops->egress_block_set) {
1150 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported");
1151 return -EOPNOTSUPP;
1152 }
1153 sch->ops->egress_block_set(sch, block_index);
1154 }
1155 return 0;
1156}
1157
1158/*
1159 Allocate and initialize new qdisc.
1160
1161 Parameters are passed via opt.
1162 */
1163
1164static struct Qdisc *qdisc_create(struct net_device *dev,
1165 struct netdev_queue *dev_queue,
1166 struct Qdisc *p, u32 parent, u32 handle,
1167 struct nlattr **tca, int *errp,
1168 struct netlink_ext_ack *extack)
1169{
1170 int err;
1171 struct nlattr *kind = tca[TCA_KIND];
1172 struct Qdisc *sch;
1173 struct Qdisc_ops *ops;
1174 struct qdisc_size_table *stab;
1175
1176 ops = qdisc_lookup_ops(kind);
1177#ifdef CONFIG_MODULES
1178 if (ops == NULL && kind != NULL) {
1179 char name[IFNAMSIZ];
1180 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) {
1181 /* We dropped the RTNL semaphore in order to
1182 * perform the module load. So, even if we
1183 * succeeded in loading the module we have to
1184 * tell the caller to replay the request. We
1185 * indicate this using -EAGAIN.
1186 * We replay the request because the device may
1187 * go away in the mean time.
1188 */
1189 rtnl_unlock();
1190 request_module("sch_%s", name);
1191 rtnl_lock();
1192 ops = qdisc_lookup_ops(kind);
1193 if (ops != NULL) {
1194 /* We will try again qdisc_lookup_ops,
1195 * so don't keep a reference.
1196 */
1197 module_put(ops->owner);
1198 err = -EAGAIN;
1199 goto err_out;
1200 }
1201 }
1202 }
1203#endif
1204
1205 err = -ENOENT;
1206 if (!ops) {
1207 NL_SET_ERR_MSG(extack, "Specified qdisc not found");
1208 goto err_out;
1209 }
1210
1211 sch = qdisc_alloc(dev_queue, ops, extack);
1212 if (IS_ERR(sch)) {
1213 err = PTR_ERR(sch);
1214 goto err_out2;
1215 }
1216
1217 sch->parent = parent;
1218
1219 if (handle == TC_H_INGRESS) {
1220 sch->flags |= TCQ_F_INGRESS;
1221 handle = TC_H_MAKE(TC_H_INGRESS, 0);
1222 } else {
1223 if (handle == 0) {
1224 handle = qdisc_alloc_handle(dev);
1225 if (handle == 0) {
1226 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded");
1227 err = -ENOSPC;
1228 goto err_out3;
1229 }
1230 }
1231 if (!netif_is_multiqueue(dev))
1232 sch->flags |= TCQ_F_ONETXQUEUE;
1233 }
1234
1235 sch->handle = handle;
1236
1237 /* This exist to keep backward compatible with a userspace
1238 * loophole, what allowed userspace to get IFF_NO_QUEUE
1239 * facility on older kernels by setting tx_queue_len=0 (prior
1240 * to qdisc init), and then forgot to reinit tx_queue_len
1241 * before again attaching a qdisc.
1242 */
1243 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) {
1244 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
1245 netdev_info(dev, "Caught tx_queue_len zero misconfig\n");
1246 }
1247
1248 err = qdisc_block_indexes_set(sch, tca, extack);
1249 if (err)
1250 goto err_out3;
1251
1252 if (ops->init) {
1253 err = ops->init(sch, tca[TCA_OPTIONS], extack);
1254 if (err != 0)
1255 goto err_out5;
1256 }
1257
1258 if (tca[TCA_STAB]) {
1259 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1260 if (IS_ERR(stab)) {
1261 err = PTR_ERR(stab);
1262 goto err_out4;
1263 }
1264 rcu_assign_pointer(sch->stab, stab);
1265 }
1266 if (tca[TCA_RATE]) {
1267 seqcount_t *running;
1268
1269 err = -EOPNOTSUPP;
1270 if (sch->flags & TCQ_F_MQROOT) {
1271 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc");
1272 goto err_out4;
1273 }
1274
1275 if (sch->parent != TC_H_ROOT &&
1276 !(sch->flags & TCQ_F_INGRESS) &&
1277 (!p || !(p->flags & TCQ_F_MQROOT)))
1278 running = qdisc_root_sleeping_running(sch);
1279 else
1280 running = &sch->running;
1281
1282 err = gen_new_estimator(&sch->bstats,
1283 sch->cpu_bstats,
1284 &sch->rate_est,
1285 NULL,
1286 running,
1287 tca[TCA_RATE]);
1288 if (err) {
1289 NL_SET_ERR_MSG(extack, "Failed to generate new estimator");
1290 goto err_out4;
1291 }
1292 }
1293
1294 qdisc_hash_add(sch, false);
1295 trace_qdisc_create(ops, dev, parent);
1296
1297 return sch;
1298
1299err_out5:
1300 /* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */
1301 if (ops->destroy)
1302 ops->destroy(sch);
1303err_out3:
1304 dev_put(dev);
1305 qdisc_free(sch);
1306err_out2:
1307 module_put(ops->owner);
1308err_out:
1309 *errp = err;
1310 return NULL;
1311
1312err_out4:
1313 /*
1314 * Any broken qdiscs that would require a ops->reset() here?
1315 * The qdisc was never in action so it shouldn't be necessary.
1316 */
1317 qdisc_put_stab(rtnl_dereference(sch->stab));
1318 if (ops->destroy)
1319 ops->destroy(sch);
1320 goto err_out3;
1321}
1322
1323static int qdisc_change(struct Qdisc *sch, struct nlattr **tca,
1324 struct netlink_ext_ack *extack)
1325{
1326 struct qdisc_size_table *ostab, *stab = NULL;
1327 int err = 0;
1328
1329 if (tca[TCA_OPTIONS]) {
1330 if (!sch->ops->change) {
1331 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc");
1332 return -EINVAL;
1333 }
1334 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
1335 NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
1336 return -EOPNOTSUPP;
1337 }
1338 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack);
1339 if (err)
1340 return err;
1341 }
1342
1343 if (tca[TCA_STAB]) {
1344 stab = qdisc_get_stab(tca[TCA_STAB], extack);
1345 if (IS_ERR(stab))
1346 return PTR_ERR(stab);
1347 }
1348
1349 ostab = rtnl_dereference(sch->stab);
1350 rcu_assign_pointer(sch->stab, stab);
1351 qdisc_put_stab(ostab);
1352
1353 if (tca[TCA_RATE]) {
1354 /* NB: ignores errors from replace_estimator
1355 because change can't be undone. */
1356 if (sch->flags & TCQ_F_MQROOT)
1357 goto out;
1358 gen_replace_estimator(&sch->bstats,
1359 sch->cpu_bstats,
1360 &sch->rate_est,
1361 NULL,
1362 qdisc_root_sleeping_running(sch),
1363 tca[TCA_RATE]);
1364 }
1365out:
1366 return 0;
1367}
1368
1369struct check_loop_arg {
1370 struct qdisc_walker w;
1371 struct Qdisc *p;
1372 int depth;
1373};
1374
1375static int check_loop_fn(struct Qdisc *q, unsigned long cl,
1376 struct qdisc_walker *w);
1377
1378static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
1379{
1380 struct check_loop_arg arg;
1381
1382 if (q->ops->cl_ops == NULL)
1383 return 0;
1384
1385 arg.w.stop = arg.w.skip = arg.w.count = 0;
1386 arg.w.fn = check_loop_fn;
1387 arg.depth = depth;
1388 arg.p = p;
1389 q->ops->cl_ops->walk(q, &arg.w);
1390 return arg.w.stop ? -ELOOP : 0;
1391}
1392
1393static int
1394check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
1395{
1396 struct Qdisc *leaf;
1397 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1398 struct check_loop_arg *arg = (struct check_loop_arg *)w;
1399
1400 leaf = cops->leaf(q, cl);
1401 if (leaf) {
1402 if (leaf == arg->p || arg->depth > 7)
1403 return -ELOOP;
1404 return check_loop(leaf, arg->p, arg->depth + 1);
1405 }
1406 return 0;
1407}
1408
1409const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = {
1410 [TCA_KIND] = { .type = NLA_STRING },
1411 [TCA_RATE] = { .type = NLA_BINARY,
1412 .len = sizeof(struct tc_estimator) },
1413 [TCA_STAB] = { .type = NLA_NESTED },
1414 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG },
1415 [TCA_CHAIN] = { .type = NLA_U32 },
1416 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 },
1417 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 },
1418};
1419
1420/*
1421 * Delete/get qdisc.
1422 */
1423
1424static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1425 struct netlink_ext_ack *extack)
1426{
1427 struct net *net = sock_net(skb->sk);
1428 struct tcmsg *tcm = nlmsg_data(n);
1429 struct nlattr *tca[TCA_MAX + 1];
1430 struct net_device *dev;
1431 u32 clid;
1432 struct Qdisc *q = NULL;
1433 struct Qdisc *p = NULL;
1434 int err;
1435
1436 if ((n->nlmsg_type != RTM_GETQDISC) &&
1437 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1438 return -EPERM;
1439
1440 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1441 rtm_tca_policy, extack);
1442 if (err < 0)
1443 return err;
1444
1445 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1446 if (!dev)
1447 return -ENODEV;
1448
1449 clid = tcm->tcm_parent;
1450 if (clid) {
1451 if (clid != TC_H_ROOT) {
1452 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
1453 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1454 if (!p) {
1455 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid");
1456 return -ENOENT;
1457 }
1458 q = qdisc_leaf(p, clid);
1459 } else if (dev_ingress_queue(dev)) {
1460 q = dev_ingress_queue(dev)->qdisc_sleeping;
1461 }
1462 } else {
1463 q = dev->qdisc;
1464 }
1465 if (!q) {
1466 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device");
1467 return -ENOENT;
1468 }
1469
1470 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) {
1471 NL_SET_ERR_MSG(extack, "Invalid handle");
1472 return -EINVAL;
1473 }
1474 } else {
1475 q = qdisc_lookup(dev, tcm->tcm_handle);
1476 if (!q) {
1477 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle");
1478 return -ENOENT;
1479 }
1480 }
1481
1482 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1483 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1484 return -EINVAL;
1485 }
1486
1487 if (n->nlmsg_type == RTM_DELQDISC) {
1488 if (!clid) {
1489 NL_SET_ERR_MSG(extack, "Classid cannot be zero");
1490 return -EINVAL;
1491 }
1492 if (q->handle == 0) {
1493 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero");
1494 return -ENOENT;
1495 }
1496 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack);
1497 if (err != 0)
1498 return err;
1499 } else {
1500 qdisc_notify(net, skb, n, clid, NULL, q);
1501 }
1502 return 0;
1503}
1504
1505/*
1506 * Create/change qdisc.
1507 */
1508
1509static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
1510 struct netlink_ext_ack *extack)
1511{
1512 struct net *net = sock_net(skb->sk);
1513 struct tcmsg *tcm;
1514 struct nlattr *tca[TCA_MAX + 1];
1515 struct net_device *dev;
1516 u32 clid;
1517 struct Qdisc *q, *p;
1518 int err;
1519
1520 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1521 return -EPERM;
1522
1523replay:
1524 /* Reinit, just in case something touches this. */
1525 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
1526 rtm_tca_policy, extack);
1527 if (err < 0)
1528 return err;
1529
1530 tcm = nlmsg_data(n);
1531 clid = tcm->tcm_parent;
1532 q = p = NULL;
1533
1534 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
1535 if (!dev)
1536 return -ENODEV;
1537
1538
1539 if (clid) {
1540 if (clid != TC_H_ROOT) {
1541 if (clid != TC_H_INGRESS) {
1542 p = qdisc_lookup(dev, TC_H_MAJ(clid));
1543 if (!p) {
1544 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc");
1545 return -ENOENT;
1546 }
1547 q = qdisc_leaf(p, clid);
1548 } else if (dev_ingress_queue_create(dev)) {
1549 q = dev_ingress_queue(dev)->qdisc_sleeping;
1550 }
1551 } else {
1552 q = dev->qdisc;
1553 }
1554
1555 /* It may be default qdisc, ignore it */
1556 if (q && q->handle == 0)
1557 q = NULL;
1558
1559 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1560 if (tcm->tcm_handle) {
1561 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) {
1562 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override");
1563 return -EEXIST;
1564 }
1565 if (TC_H_MIN(tcm->tcm_handle)) {
1566 NL_SET_ERR_MSG(extack, "Invalid minor handle");
1567 return -EINVAL;
1568 }
1569 q = qdisc_lookup(dev, tcm->tcm_handle);
1570 if (!q)
1571 goto create_n_graft;
1572 if (n->nlmsg_flags & NLM_F_EXCL) {
1573 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override");
1574 return -EEXIST;
1575 }
1576 if (tca[TCA_KIND] &&
1577 nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1578 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1579 return -EINVAL;
1580 }
1581 if (q == p ||
1582 (p && check_loop(q, p, 0))) {
1583 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected");
1584 return -ELOOP;
1585 }
1586 qdisc_refcount_inc(q);
1587 goto graft;
1588 } else {
1589 if (!q)
1590 goto create_n_graft;
1591
1592 /* This magic test requires explanation.
1593 *
1594 * We know, that some child q is already
1595 * attached to this parent and have choice:
1596 * either to change it or to create/graft new one.
1597 *
1598 * 1. We are allowed to create/graft only
1599 * if CREATE and REPLACE flags are set.
1600 *
1601 * 2. If EXCL is set, requestor wanted to say,
1602 * that qdisc tcm_handle is not expected
1603 * to exist, so that we choose create/graft too.
1604 *
1605 * 3. The last case is when no flags are set.
1606 * Alas, it is sort of hole in API, we
1607 * cannot decide what to do unambiguously.
1608 * For now we select create/graft, if
1609 * user gave KIND, which does not match existing.
1610 */
1611 if ((n->nlmsg_flags & NLM_F_CREATE) &&
1612 (n->nlmsg_flags & NLM_F_REPLACE) &&
1613 ((n->nlmsg_flags & NLM_F_EXCL) ||
1614 (tca[TCA_KIND] &&
1615 nla_strcmp(tca[TCA_KIND], q->ops->id))))
1616 goto create_n_graft;
1617 }
1618 }
1619 } else {
1620 if (!tcm->tcm_handle) {
1621 NL_SET_ERR_MSG(extack, "Handle cannot be zero");
1622 return -EINVAL;
1623 }
1624 q = qdisc_lookup(dev, tcm->tcm_handle);
1625 }
1626
1627 /* Change qdisc parameters */
1628 if (!q) {
1629 NL_SET_ERR_MSG(extack, "Specified qdisc not found");
1630 return -ENOENT;
1631 }
1632 if (n->nlmsg_flags & NLM_F_EXCL) {
1633 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify");
1634 return -EEXIST;
1635 }
1636 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) {
1637 NL_SET_ERR_MSG(extack, "Invalid qdisc name");
1638 return -EINVAL;
1639 }
1640 err = qdisc_change(q, tca, extack);
1641 if (err == 0)
1642 qdisc_notify(net, skb, n, clid, NULL, q);
1643 return err;
1644
1645create_n_graft:
1646 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
1647 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag");
1648 return -ENOENT;
1649 }
1650 if (clid == TC_H_INGRESS) {
1651 if (dev_ingress_queue(dev)) {
1652 q = qdisc_create(dev, dev_ingress_queue(dev), p,
1653 tcm->tcm_parent, tcm->tcm_parent,
1654 tca, &err, extack);
1655 } else {
1656 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device");
1657 err = -ENOENT;
1658 }
1659 } else {
1660 struct netdev_queue *dev_queue;
1661
1662 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1663 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1664 else if (p)
1665 dev_queue = p->dev_queue;
1666 else
1667 dev_queue = netdev_get_tx_queue(dev, 0);
1668
1669 q = qdisc_create(dev, dev_queue, p,
1670 tcm->tcm_parent, tcm->tcm_handle,
1671 tca, &err, extack);
1672 }
1673 if (q == NULL) {
1674 if (err == -EAGAIN)
1675 goto replay;
1676 return err;
1677 }
1678
1679graft:
1680 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack);
1681 if (err) {
1682 if (q)
1683 qdisc_put(q);
1684 return err;
1685 }
1686
1687 return 0;
1688}
1689
1690static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1691 struct netlink_callback *cb,
1692 int *q_idx_p, int s_q_idx, bool recur,
1693 bool dump_invisible)
1694{
1695 int ret = 0, q_idx = *q_idx_p;
1696 struct Qdisc *q;
1697 int b;
1698
1699 if (!root)
1700 return 0;
1701
1702 q = root;
1703 if (q_idx < s_q_idx) {
1704 q_idx++;
1705 } else {
1706 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1707 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1708 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1709 RTM_NEWQDISC) <= 0)
1710 goto done;
1711 q_idx++;
1712 }
1713
1714 /* If dumping singletons, there is no qdisc_dev(root) and the singleton
1715 * itself has already been dumped.
1716 *
1717 * If we've already dumped the top-level (ingress) qdisc above and the global
1718 * qdisc hashtable, we don't want to hit it again
1719 */
1720 if (!qdisc_dev(root) || !recur)
1721 goto out;
1722
1723 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
1724 if (q_idx < s_q_idx) {
1725 q_idx++;
1726 continue;
1727 }
1728 if (!tc_qdisc_dump_ignore(q, dump_invisible) &&
1729 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid,
1730 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1731 RTM_NEWQDISC) <= 0)
1732 goto done;
1733 q_idx++;
1734 }
1735
1736out:
1737 *q_idx_p = q_idx;
1738 return ret;
1739done:
1740 ret = -1;
1741 goto out;
1742}
1743
1744static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1745{
1746 struct net *net = sock_net(skb->sk);
1747 int idx, q_idx;
1748 int s_idx, s_q_idx;
1749 struct net_device *dev;
1750 const struct nlmsghdr *nlh = cb->nlh;
1751 struct nlattr *tca[TCA_MAX + 1];
1752 int err;
1753
1754 s_idx = cb->args[0];
1755 s_q_idx = q_idx = cb->args[1];
1756
1757 idx = 0;
1758 ASSERT_RTNL();
1759
1760 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX,
1761 rtm_tca_policy, cb->extack);
1762 if (err < 0)
1763 return err;
1764
1765 for_each_netdev(net, dev) {
1766 struct netdev_queue *dev_queue;
1767
1768 if (idx < s_idx)
1769 goto cont;
1770 if (idx > s_idx)
1771 s_q_idx = 0;
1772 q_idx = 0;
1773
1774 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx,
1775 true, tca[TCA_DUMP_INVISIBLE]) < 0)
1776 goto done;
1777
1778 dev_queue = dev_ingress_queue(dev);
1779 if (dev_queue &&
1780 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb,
1781 &q_idx, s_q_idx, false,
1782 tca[TCA_DUMP_INVISIBLE]) < 0)
1783 goto done;
1784
1785cont:
1786 idx++;
1787 }
1788
1789done:
1790 cb->args[0] = idx;
1791 cb->args[1] = q_idx;
1792
1793 return skb->len;
1794}
1795
1796
1797
1798/************************************************
1799 * Traffic classes manipulation. *
1800 ************************************************/
1801
1802static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1803 unsigned long cl,
1804 u32 portid, u32 seq, u16 flags, int event)
1805{
1806 struct tcmsg *tcm;
1807 struct nlmsghdr *nlh;
1808 unsigned char *b = skb_tail_pointer(skb);
1809 struct gnet_dump d;
1810 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1811
1812 cond_resched();
1813 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1814 if (!nlh)
1815 goto out_nlmsg_trim;
1816 tcm = nlmsg_data(nlh);
1817 tcm->tcm_family = AF_UNSPEC;
1818 tcm->tcm__pad1 = 0;
1819 tcm->tcm__pad2 = 0;
1820 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1821 tcm->tcm_parent = q->handle;
1822 tcm->tcm_handle = q->handle;
1823 tcm->tcm_info = 0;
1824 if (nla_put_string(skb, TCA_KIND, q->ops->id))
1825 goto nla_put_failure;
1826 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1827 goto nla_put_failure;
1828
1829 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1830 NULL, &d, TCA_PAD) < 0)
1831 goto nla_put_failure;
1832
1833 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1834 goto nla_put_failure;
1835
1836 if (gnet_stats_finish_copy(&d) < 0)
1837 goto nla_put_failure;
1838
1839 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1840 return skb->len;
1841
1842out_nlmsg_trim:
1843nla_put_failure:
1844 nlmsg_trim(skb, b);
1845 return -1;
1846}
1847
1848static int tclass_notify(struct net *net, struct sk_buff *oskb,
1849 struct nlmsghdr *n, struct Qdisc *q,
1850 unsigned long cl, int event)
1851{
1852 struct sk_buff *skb;
1853 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1854 int err = 0;
1855
1856 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1857 if (!skb)
1858 return -ENOBUFS;
1859
1860 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) {
1861 kfree_skb(skb);
1862 return -EINVAL;
1863 }
1864
1865 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1866 n->nlmsg_flags & NLM_F_ECHO);
1867 if (err > 0)
1868 err = 0;
1869 return err;
1870}
1871
1872static int tclass_del_notify(struct net *net,
1873 const struct Qdisc_class_ops *cops,
1874 struct sk_buff *oskb, struct nlmsghdr *n,
1875 struct Qdisc *q, unsigned long cl,
1876 struct netlink_ext_ack *extack)
1877{
1878 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1879 struct sk_buff *skb;
1880 int err = 0;
1881
1882 if (!cops->delete)
1883 return -EOPNOTSUPP;
1884
1885 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1886 if (!skb)
1887 return -ENOBUFS;
1888
1889 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0,
1890 RTM_DELTCLASS) < 0) {
1891 kfree_skb(skb);
1892 return -EINVAL;
1893 }
1894
1895 err = cops->delete(q, cl, extack);
1896 if (err) {
1897 kfree_skb(skb);
1898 return err;
1899 }
1900
1901 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1902 n->nlmsg_flags & NLM_F_ECHO);
1903 if (err > 0)
1904 err = 0;
1905 return err;
1906}
1907
1908#ifdef CONFIG_NET_CLS
1909
1910struct tcf_bind_args {
1911 struct tcf_walker w;
1912 unsigned long base;
1913 unsigned long cl;
1914 u32 classid;
1915};
1916
1917static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
1918{
1919 struct tcf_bind_args *a = (void *)arg;
1920
1921 if (tp->ops->bind_class) {
1922 struct Qdisc *q = tcf_block_q(tp->chain->block);
1923
1924 sch_tree_lock(q);
1925 tp->ops->bind_class(n, a->classid, a->cl, q, a->base);
1926 sch_tree_unlock(q);
1927 }
1928 return 0;
1929}
1930
1931struct tc_bind_class_args {
1932 struct qdisc_walker w;
1933 unsigned long new_cl;
1934 u32 portid;
1935 u32 clid;
1936};
1937
1938static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl,
1939 struct qdisc_walker *w)
1940{
1941 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w;
1942 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1943 struct tcf_block *block;
1944 struct tcf_chain *chain;
1945
1946 block = cops->tcf_block(q, cl, NULL);
1947 if (!block)
1948 return 0;
1949 for (chain = tcf_get_next_chain(block, NULL);
1950 chain;
1951 chain = tcf_get_next_chain(block, chain)) {
1952 struct tcf_proto *tp;
1953
1954 for (tp = tcf_get_next_proto(chain, NULL);
1955 tp; tp = tcf_get_next_proto(chain, tp)) {
1956 struct tcf_bind_args arg = {};
1957
1958 arg.w.fn = tcf_node_bind;
1959 arg.classid = a->clid;
1960 arg.base = cl;
1961 arg.cl = a->new_cl;
1962 tp->ops->walk(tp, &arg.w, true);
1963 }
1964 }
1965
1966 return 0;
1967}
1968
1969static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
1970 unsigned long new_cl)
1971{
1972 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1973 struct tc_bind_class_args args = {};
1974
1975 if (!cops->tcf_block)
1976 return;
1977 args.portid = portid;
1978 args.clid = clid;
1979 args.new_cl = new_cl;
1980 args.w.fn = tc_bind_class_walker;
1981 q->ops->cl_ops->walk(q, &args.w);
1982}
1983
1984#else
1985
1986static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid,
1987 unsigned long new_cl)
1988{
1989}
1990
1991#endif
1992
1993static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n,
1994 struct netlink_ext_ack *extack)
1995{
1996 struct net *net = sock_net(skb->sk);
1997 struct tcmsg *tcm = nlmsg_data(n);
1998 struct nlattr *tca[TCA_MAX + 1];
1999 struct net_device *dev;
2000 struct Qdisc *q = NULL;
2001 const struct Qdisc_class_ops *cops;
2002 unsigned long cl = 0;
2003 unsigned long new_cl;
2004 u32 portid;
2005 u32 clid;
2006 u32 qid;
2007 int err;
2008
2009 if ((n->nlmsg_type != RTM_GETTCLASS) &&
2010 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2011 return -EPERM;
2012
2013 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX,
2014 rtm_tca_policy, extack);
2015 if (err < 0)
2016 return err;
2017
2018 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2019 if (!dev)
2020 return -ENODEV;
2021
2022 /*
2023 parent == TC_H_UNSPEC - unspecified parent.
2024 parent == TC_H_ROOT - class is root, which has no parent.
2025 parent == X:0 - parent is root class.
2026 parent == X:Y - parent is a node in hierarchy.
2027 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
2028
2029 handle == 0:0 - generate handle from kernel pool.
2030 handle == 0:Y - class is X:Y, where X:0 is qdisc.
2031 handle == X:Y - clear.
2032 handle == X:0 - root class.
2033 */
2034
2035 /* Step 1. Determine qdisc handle X:0 */
2036
2037 portid = tcm->tcm_parent;
2038 clid = tcm->tcm_handle;
2039 qid = TC_H_MAJ(clid);
2040
2041 if (portid != TC_H_ROOT) {
2042 u32 qid1 = TC_H_MAJ(portid);
2043
2044 if (qid && qid1) {
2045 /* If both majors are known, they must be identical. */
2046 if (qid != qid1)
2047 return -EINVAL;
2048 } else if (qid1) {
2049 qid = qid1;
2050 } else if (qid == 0)
2051 qid = dev->qdisc->handle;
2052
2053 /* Now qid is genuine qdisc handle consistent
2054 * both with parent and child.
2055 *
2056 * TC_H_MAJ(portid) still may be unspecified, complete it now.
2057 */
2058 if (portid)
2059 portid = TC_H_MAKE(qid, portid);
2060 } else {
2061 if (qid == 0)
2062 qid = dev->qdisc->handle;
2063 }
2064
2065 /* OK. Locate qdisc */
2066 q = qdisc_lookup(dev, qid);
2067 if (!q)
2068 return -ENOENT;
2069
2070 /* An check that it supports classes */
2071 cops = q->ops->cl_ops;
2072 if (cops == NULL)
2073 return -EINVAL;
2074
2075 /* Now try to get class */
2076 if (clid == 0) {
2077 if (portid == TC_H_ROOT)
2078 clid = qid;
2079 } else
2080 clid = TC_H_MAKE(qid, clid);
2081
2082 if (clid)
2083 cl = cops->find(q, clid);
2084
2085 if (cl == 0) {
2086 err = -ENOENT;
2087 if (n->nlmsg_type != RTM_NEWTCLASS ||
2088 !(n->nlmsg_flags & NLM_F_CREATE))
2089 goto out;
2090 } else {
2091 switch (n->nlmsg_type) {
2092 case RTM_NEWTCLASS:
2093 err = -EEXIST;
2094 if (n->nlmsg_flags & NLM_F_EXCL)
2095 goto out;
2096 break;
2097 case RTM_DELTCLASS:
2098 err = tclass_del_notify(net, cops, skb, n, q, cl, extack);
2099 /* Unbind the class with flilters with 0 */
2100 tc_bind_tclass(q, portid, clid, 0);
2101 goto out;
2102 case RTM_GETTCLASS:
2103 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS);
2104 goto out;
2105 default:
2106 err = -EINVAL;
2107 goto out;
2108 }
2109 }
2110
2111 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) {
2112 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes");
2113 return -EOPNOTSUPP;
2114 }
2115
2116 new_cl = cl;
2117 err = -EOPNOTSUPP;
2118 if (cops->change)
2119 err = cops->change(q, clid, portid, tca, &new_cl, extack);
2120 if (err == 0) {
2121 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS);
2122 /* We just create a new class, need to do reverse binding. */
2123 if (cl != new_cl)
2124 tc_bind_tclass(q, portid, clid, new_cl);
2125 }
2126out:
2127 return err;
2128}
2129
2130struct qdisc_dump_args {
2131 struct qdisc_walker w;
2132 struct sk_buff *skb;
2133 struct netlink_callback *cb;
2134};
2135
2136static int qdisc_class_dump(struct Qdisc *q, unsigned long cl,
2137 struct qdisc_walker *arg)
2138{
2139 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
2140
2141 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid,
2142 a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2143 RTM_NEWTCLASS);
2144}
2145
2146static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
2147 struct tcmsg *tcm, struct netlink_callback *cb,
2148 int *t_p, int s_t)
2149{
2150 struct qdisc_dump_args arg;
2151
2152 if (tc_qdisc_dump_ignore(q, false) ||
2153 *t_p < s_t || !q->ops->cl_ops ||
2154 (tcm->tcm_parent &&
2155 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
2156 (*t_p)++;
2157 return 0;
2158 }
2159 if (*t_p > s_t)
2160 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
2161 arg.w.fn = qdisc_class_dump;
2162 arg.skb = skb;
2163 arg.cb = cb;
2164 arg.w.stop = 0;
2165 arg.w.skip = cb->args[1];
2166 arg.w.count = 0;
2167 q->ops->cl_ops->walk(q, &arg.w);
2168 cb->args[1] = arg.w.count;
2169 if (arg.w.stop)
2170 return -1;
2171 (*t_p)++;
2172 return 0;
2173}
2174
2175static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
2176 struct tcmsg *tcm, struct netlink_callback *cb,
2177 int *t_p, int s_t, bool recur)
2178{
2179 struct Qdisc *q;
2180 int b;
2181
2182 if (!root)
2183 return 0;
2184
2185 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
2186 return -1;
2187
2188 if (!qdisc_dev(root) || !recur)
2189 return 0;
2190
2191 if (tcm->tcm_parent) {
2192 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent));
2193 if (q && q != root &&
2194 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2195 return -1;
2196 return 0;
2197 }
2198 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) {
2199 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
2200 return -1;
2201 }
2202
2203 return 0;
2204}
2205
2206static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
2207{
2208 struct tcmsg *tcm = nlmsg_data(cb->nlh);
2209 struct net *net = sock_net(skb->sk);
2210 struct netdev_queue *dev_queue;
2211 struct net_device *dev;
2212 int t, s_t;
2213
2214 if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2215 return 0;
2216 dev = dev_get_by_index(net, tcm->tcm_ifindex);
2217 if (!dev)
2218 return 0;
2219
2220 s_t = cb->args[0];
2221 t = 0;
2222
2223 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t, true) < 0)
2224 goto done;
2225
2226 dev_queue = dev_ingress_queue(dev);
2227 if (dev_queue &&
2228 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb,
2229 &t, s_t, false) < 0)
2230 goto done;
2231
2232done:
2233 cb->args[0] = t;
2234
2235 dev_put(dev);
2236 return skb->len;
2237}
2238
2239#ifdef CONFIG_PROC_FS
2240static int psched_show(struct seq_file *seq, void *v)
2241{
2242 seq_printf(seq, "%08x %08x %08x %08x\n",
2243 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
2244 1000000,
2245 (u32)NSEC_PER_SEC / hrtimer_resolution);
2246
2247 return 0;
2248}
2249
2250static int __net_init psched_net_init(struct net *net)
2251{
2252 struct proc_dir_entry *e;
2253
2254 e = proc_create_single("psched", 0, net->proc_net, psched_show);
2255 if (e == NULL)
2256 return -ENOMEM;
2257
2258 return 0;
2259}
2260
2261static void __net_exit psched_net_exit(struct net *net)
2262{
2263 remove_proc_entry("psched", net->proc_net);
2264}
2265#else
2266static int __net_init psched_net_init(struct net *net)
2267{
2268 return 0;
2269}
2270
2271static void __net_exit psched_net_exit(struct net *net)
2272{
2273}
2274#endif
2275
2276static struct pernet_operations psched_net_ops = {
2277 .init = psched_net_init,
2278 .exit = psched_net_exit,
2279};
2280
2281static int __init pktsched_init(void)
2282{
2283 int err;
2284
2285 err = register_pernet_subsys(&psched_net_ops);
2286 if (err) {
2287 pr_err("pktsched_init: "
2288 "cannot initialize per netns operations\n");
2289 return err;
2290 }
2291
2292 register_qdisc(&pfifo_fast_ops);
2293 register_qdisc(&pfifo_qdisc_ops);
2294 register_qdisc(&bfifo_qdisc_ops);
2295 register_qdisc(&pfifo_head_drop_qdisc_ops);
2296 register_qdisc(&mq_qdisc_ops);
2297 register_qdisc(&noqueue_qdisc_ops);
2298
2299 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0);
2300 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0);
2301 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc,
2302 0);
2303 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0);
2304 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0);
2305 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass,
2306 0);
2307
2308 return 0;
2309}
2310
2311subsys_initcall(pktsched_init);