Save sram context after changing MPU, DSP or core clocks
[linux-ginger.git] / net / sched / sch_api.c
blob903e4188b6ca1057426f8327f0bb1d69f00afb0b
1 /*
2 * net/sched/sch_api.c Packet scheduler API.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
11 * Fixes:
13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/skbuff.h>
24 #include <linux/init.h>
25 #include <linux/proc_fs.h>
26 #include <linux/seq_file.h>
27 #include <linux/kmod.h>
28 #include <linux/list.h>
29 #include <linux/hrtimer.h>
30 #include <linux/lockdep.h>
32 #include <net/net_namespace.h>
33 #include <net/sock.h>
34 #include <net/netlink.h>
35 #include <net/pkt_sched.h>
37 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, u32 clid,
38 struct Qdisc *old, struct Qdisc *new);
39 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n,
40 struct Qdisc *q, unsigned long cl, int event);
44 Short review.
45 -------------
47 This file consists of two interrelated parts:
49 1. queueing disciplines manager frontend.
50 2. traffic classes manager frontend.
52 Generally, queueing discipline ("qdisc") is a black box,
53 which is able to enqueue packets and to dequeue them (when
54 device is ready to send something) in order and at times
55 determined by algorithm hidden in it.
57 qdisc's are divided to two categories:
58 - "queues", which have no internal structure visible from outside.
59 - "schedulers", which split all the packets to "traffic classes",
60 using "packet classifiers" (look at cls_api.c)
62 In turn, classes may have child qdiscs (as rule, queues)
63 attached to them etc. etc. etc.
65 The goal of the routines in this file is to translate
66 information supplied by user in the form of handles
67 to more intelligible for kernel form, to make some sanity
68 checks and part of work, which is common to all qdiscs
69 and to provide rtnetlink notifications.
71 All real intelligent work is done inside qdisc modules.
75 Every discipline has two major routines: enqueue and dequeue.
77 ---dequeue
79 dequeue usually returns a skb to send. It is allowed to return NULL,
80 but it does not mean that queue is empty, it just means that
81 discipline does not want to send anything this time.
82 Queue is really empty if q->q.qlen == 0.
83 For complicated disciplines with multiple queues q->q is not
84 real packet queue, but however q->q.qlen must be valid.
86 ---enqueue
88 enqueue returns 0, if packet was enqueued successfully.
89 If packet (this one or another one) was dropped, it returns
90 not zero error code.
91 NET_XMIT_DROP - this packet dropped
92 Expected action: do not backoff, but wait until queue will clear.
93 NET_XMIT_CN - probably this packet enqueued, but another one dropped.
94 Expected action: backoff or ignore
95 NET_XMIT_POLICED - dropped by police.
96 Expected action: backoff or error to real-time apps.
98 Auxiliary routines:
100 ---peek
102 like dequeue but without removing a packet from the queue
104 ---reset
106 returns qdisc to initial state: purge all buffers, clear all
107 timers, counters (except for statistics) etc.
109 ---init
111 initializes newly created qdisc.
113 ---destroy
115 destroys resources allocated by init and during lifetime of qdisc.
117 ---change
119 changes qdisc parameters.
122 /* Protects list of registered TC modules. It is pure SMP lock. */
123 static DEFINE_RWLOCK(qdisc_mod_lock);
126 /************************************************
127 * Queueing disciplines manipulation. *
128 ************************************************/
131 /* The list of all installed queueing disciplines. */
133 static struct Qdisc_ops *qdisc_base;
135 /* Register/uregister queueing discipline */
137 int register_qdisc(struct Qdisc_ops *qops)
139 struct Qdisc_ops *q, **qp;
140 int rc = -EEXIST;
142 write_lock(&qdisc_mod_lock);
143 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next)
144 if (!strcmp(qops->id, q->id))
145 goto out;
147 if (qops->enqueue == NULL)
148 qops->enqueue = noop_qdisc_ops.enqueue;
149 if (qops->peek == NULL) {
150 if (qops->dequeue == NULL) {
151 qops->peek = noop_qdisc_ops.peek;
152 } else {
153 rc = -EINVAL;
154 goto out;
157 if (qops->dequeue == NULL)
158 qops->dequeue = noop_qdisc_ops.dequeue;
160 qops->next = NULL;
161 *qp = qops;
162 rc = 0;
163 out:
164 write_unlock(&qdisc_mod_lock);
165 return rc;
167 EXPORT_SYMBOL(register_qdisc);
169 int unregister_qdisc(struct Qdisc_ops *qops)
171 struct Qdisc_ops *q, **qp;
172 int err = -ENOENT;
174 write_lock(&qdisc_mod_lock);
175 for (qp = &qdisc_base; (q=*qp)!=NULL; qp = &q->next)
176 if (q == qops)
177 break;
178 if (q) {
179 *qp = q->next;
180 q->next = NULL;
181 err = 0;
183 write_unlock(&qdisc_mod_lock);
184 return err;
186 EXPORT_SYMBOL(unregister_qdisc);
188 /* We know handle. Find qdisc among all qdisc's attached to device
189 (root qdisc, all its children, children of children etc.)
192 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
194 struct Qdisc *q;
196 if (!(root->flags & TCQ_F_BUILTIN) &&
197 root->handle == handle)
198 return root;
200 list_for_each_entry(q, &root->list, list) {
201 if (q->handle == handle)
202 return q;
204 return NULL;
207 static void qdisc_list_add(struct Qdisc *q)
209 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
210 list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list);
213 void qdisc_list_del(struct Qdisc *q)
215 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
216 list_del(&q->list);
218 EXPORT_SYMBOL(qdisc_list_del);
220 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
222 struct Qdisc *q;
224 q = qdisc_match_from_root(dev->qdisc, handle);
225 if (q)
226 goto out;
228 q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle);
229 out:
230 return q;
233 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
235 unsigned long cl;
236 struct Qdisc *leaf;
237 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
239 if (cops == NULL)
240 return NULL;
241 cl = cops->get(p, classid);
243 if (cl == 0)
244 return NULL;
245 leaf = cops->leaf(p, cl);
246 cops->put(p, cl);
247 return leaf;
250 /* Find queueing discipline by name */
252 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
254 struct Qdisc_ops *q = NULL;
256 if (kind) {
257 read_lock(&qdisc_mod_lock);
258 for (q = qdisc_base; q; q = q->next) {
259 if (nla_strcmp(kind, q->id) == 0) {
260 if (!try_module_get(q->owner))
261 q = NULL;
262 break;
265 read_unlock(&qdisc_mod_lock);
267 return q;
270 static struct qdisc_rate_table *qdisc_rtab_list;
272 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
274 struct qdisc_rate_table *rtab;
276 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) {
277 if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) {
278 rtab->refcnt++;
279 return rtab;
283 if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
284 nla_len(tab) != TC_RTAB_SIZE)
285 return NULL;
287 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL);
288 if (rtab) {
289 rtab->rate = *r;
290 rtab->refcnt = 1;
291 memcpy(rtab->data, nla_data(tab), 1024);
292 rtab->next = qdisc_rtab_list;
293 qdisc_rtab_list = rtab;
295 return rtab;
297 EXPORT_SYMBOL(qdisc_get_rtab);
299 void qdisc_put_rtab(struct qdisc_rate_table *tab)
301 struct qdisc_rate_table *rtab, **rtabp;
303 if (!tab || --tab->refcnt)
304 return;
306 for (rtabp = &qdisc_rtab_list; (rtab=*rtabp) != NULL; rtabp = &rtab->next) {
307 if (rtab == tab) {
308 *rtabp = rtab->next;
309 kfree(rtab);
310 return;
314 EXPORT_SYMBOL(qdisc_put_rtab);
316 static LIST_HEAD(qdisc_stab_list);
317 static DEFINE_SPINLOCK(qdisc_stab_lock);
319 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = {
320 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) },
321 [TCA_STAB_DATA] = { .type = NLA_BINARY },
324 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
326 struct nlattr *tb[TCA_STAB_MAX + 1];
327 struct qdisc_size_table *stab;
328 struct tc_sizespec *s;
329 unsigned int tsize = 0;
330 u16 *tab = NULL;
331 int err;
333 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy);
334 if (err < 0)
335 return ERR_PTR(err);
336 if (!tb[TCA_STAB_BASE])
337 return ERR_PTR(-EINVAL);
339 s = nla_data(tb[TCA_STAB_BASE]);
341 if (s->tsize > 0) {
342 if (!tb[TCA_STAB_DATA])
343 return ERR_PTR(-EINVAL);
344 tab = nla_data(tb[TCA_STAB_DATA]);
345 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
348 if (!s || tsize != s->tsize || (!tab && tsize > 0))
349 return ERR_PTR(-EINVAL);
351 spin_lock(&qdisc_stab_lock);
353 list_for_each_entry(stab, &qdisc_stab_list, list) {
354 if (memcmp(&stab->szopts, s, sizeof(*s)))
355 continue;
356 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16)))
357 continue;
358 stab->refcnt++;
359 spin_unlock(&qdisc_stab_lock);
360 return stab;
363 spin_unlock(&qdisc_stab_lock);
365 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
366 if (!stab)
367 return ERR_PTR(-ENOMEM);
369 stab->refcnt = 1;
370 stab->szopts = *s;
371 if (tsize > 0)
372 memcpy(stab->data, tab, tsize * sizeof(u16));
374 spin_lock(&qdisc_stab_lock);
375 list_add_tail(&stab->list, &qdisc_stab_list);
376 spin_unlock(&qdisc_stab_lock);
378 return stab;
381 void qdisc_put_stab(struct qdisc_size_table *tab)
383 if (!tab)
384 return;
386 spin_lock(&qdisc_stab_lock);
388 if (--tab->refcnt == 0) {
389 list_del(&tab->list);
390 kfree(tab);
393 spin_unlock(&qdisc_stab_lock);
395 EXPORT_SYMBOL(qdisc_put_stab);
397 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
399 struct nlattr *nest;
401 nest = nla_nest_start(skb, TCA_STAB);
402 if (nest == NULL)
403 goto nla_put_failure;
404 NLA_PUT(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts);
405 nla_nest_end(skb, nest);
407 return skb->len;
409 nla_put_failure:
410 return -1;
413 void qdisc_calculate_pkt_len(struct sk_buff *skb, struct qdisc_size_table *stab)
415 int pkt_len, slot;
417 pkt_len = skb->len + stab->szopts.overhead;
418 if (unlikely(!stab->szopts.tsize))
419 goto out;
421 slot = pkt_len + stab->szopts.cell_align;
422 if (unlikely(slot < 0))
423 slot = 0;
425 slot >>= stab->szopts.cell_log;
426 if (likely(slot < stab->szopts.tsize))
427 pkt_len = stab->data[slot];
428 else
429 pkt_len = stab->data[stab->szopts.tsize - 1] *
430 (slot / stab->szopts.tsize) +
431 stab->data[slot % stab->szopts.tsize];
433 pkt_len <<= stab->szopts.size_log;
434 out:
435 if (unlikely(pkt_len < 1))
436 pkt_len = 1;
437 qdisc_skb_cb(skb)->pkt_len = pkt_len;
439 EXPORT_SYMBOL(qdisc_calculate_pkt_len);
441 void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc)
443 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) {
444 printk(KERN_WARNING
445 "%s: %s qdisc %X: is non-work-conserving?\n",
446 txt, qdisc->ops->id, qdisc->handle >> 16);
447 qdisc->flags |= TCQ_F_WARN_NONWC;
450 EXPORT_SYMBOL(qdisc_warn_nonwc);
452 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
454 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
455 timer);
457 wd->qdisc->flags &= ~TCQ_F_THROTTLED;
458 __netif_schedule(qdisc_root(wd->qdisc));
460 return HRTIMER_NORESTART;
463 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
465 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
466 wd->timer.function = qdisc_watchdog;
467 wd->qdisc = qdisc;
469 EXPORT_SYMBOL(qdisc_watchdog_init);
471 void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires)
473 ktime_t time;
475 if (test_bit(__QDISC_STATE_DEACTIVATED,
476 &qdisc_root_sleeping(wd->qdisc)->state))
477 return;
479 wd->qdisc->flags |= TCQ_F_THROTTLED;
480 time = ktime_set(0, 0);
481 time = ktime_add_ns(time, PSCHED_TICKS2NS(expires));
482 hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS);
484 EXPORT_SYMBOL(qdisc_watchdog_schedule);
486 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
488 hrtimer_cancel(&wd->timer);
489 wd->qdisc->flags &= ~TCQ_F_THROTTLED;
491 EXPORT_SYMBOL(qdisc_watchdog_cancel);
493 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
495 unsigned int size = n * sizeof(struct hlist_head), i;
496 struct hlist_head *h;
498 if (size <= PAGE_SIZE)
499 h = kmalloc(size, GFP_KERNEL);
500 else
501 h = (struct hlist_head *)
502 __get_free_pages(GFP_KERNEL, get_order(size));
504 if (h != NULL) {
505 for (i = 0; i < n; i++)
506 INIT_HLIST_HEAD(&h[i]);
508 return h;
511 static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
513 unsigned int size = n * sizeof(struct hlist_head);
515 if (size <= PAGE_SIZE)
516 kfree(h);
517 else
518 free_pages((unsigned long)h, get_order(size));
521 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
523 struct Qdisc_class_common *cl;
524 struct hlist_node *n, *next;
525 struct hlist_head *nhash, *ohash;
526 unsigned int nsize, nmask, osize;
527 unsigned int i, h;
529 /* Rehash when load factor exceeds 0.75 */
530 if (clhash->hashelems * 4 <= clhash->hashsize * 3)
531 return;
532 nsize = clhash->hashsize * 2;
533 nmask = nsize - 1;
534 nhash = qdisc_class_hash_alloc(nsize);
535 if (nhash == NULL)
536 return;
538 ohash = clhash->hash;
539 osize = clhash->hashsize;
541 sch_tree_lock(sch);
542 for (i = 0; i < osize; i++) {
543 hlist_for_each_entry_safe(cl, n, next, &ohash[i], hnode) {
544 h = qdisc_class_hash(cl->classid, nmask);
545 hlist_add_head(&cl->hnode, &nhash[h]);
548 clhash->hash = nhash;
549 clhash->hashsize = nsize;
550 clhash->hashmask = nmask;
551 sch_tree_unlock(sch);
553 qdisc_class_hash_free(ohash, osize);
555 EXPORT_SYMBOL(qdisc_class_hash_grow);
557 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
559 unsigned int size = 4;
561 clhash->hash = qdisc_class_hash_alloc(size);
562 if (clhash->hash == NULL)
563 return -ENOMEM;
564 clhash->hashsize = size;
565 clhash->hashmask = size - 1;
566 clhash->hashelems = 0;
567 return 0;
569 EXPORT_SYMBOL(qdisc_class_hash_init);
571 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
573 qdisc_class_hash_free(clhash->hash, clhash->hashsize);
575 EXPORT_SYMBOL(qdisc_class_hash_destroy);
577 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
578 struct Qdisc_class_common *cl)
580 unsigned int h;
582 INIT_HLIST_NODE(&cl->hnode);
583 h = qdisc_class_hash(cl->classid, clhash->hashmask);
584 hlist_add_head(&cl->hnode, &clhash->hash[h]);
585 clhash->hashelems++;
587 EXPORT_SYMBOL(qdisc_class_hash_insert);
589 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
590 struct Qdisc_class_common *cl)
592 hlist_del(&cl->hnode);
593 clhash->hashelems--;
595 EXPORT_SYMBOL(qdisc_class_hash_remove);
597 /* Allocate an unique handle from space managed by kernel */
599 static u32 qdisc_alloc_handle(struct net_device *dev)
601 int i = 0x10000;
602 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
604 do {
605 autohandle += TC_H_MAKE(0x10000U, 0);
606 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0))
607 autohandle = TC_H_MAKE(0x80000000U, 0);
608 } while (qdisc_lookup(dev, autohandle) && --i > 0);
610 return i>0 ? autohandle : 0;
613 void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
615 const struct Qdisc_class_ops *cops;
616 unsigned long cl;
617 u32 parentid;
619 if (n == 0)
620 return;
621 while ((parentid = sch->parent)) {
622 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS))
623 return;
625 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
626 if (sch == NULL) {
627 WARN_ON(parentid != TC_H_ROOT);
628 return;
630 cops = sch->ops->cl_ops;
631 if (cops->qlen_notify) {
632 cl = cops->get(sch, parentid);
633 cops->qlen_notify(sch, cl);
634 cops->put(sch, cl);
636 sch->q.qlen -= n;
639 EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
641 static void notify_and_destroy(struct sk_buff *skb, struct nlmsghdr *n, u32 clid,
642 struct Qdisc *old, struct Qdisc *new)
644 if (new || old)
645 qdisc_notify(skb, n, clid, old, new);
647 if (old)
648 qdisc_destroy(old);
651 /* Graft qdisc "new" to class "classid" of qdisc "parent" or
652 * to device "dev".
654 * When appropriate send a netlink notification using 'skb'
655 * and "n".
657 * On success, destroy old qdisc.
660 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
661 struct sk_buff *skb, struct nlmsghdr *n, u32 classid,
662 struct Qdisc *new, struct Qdisc *old)
664 struct Qdisc *q = old;
665 int err = 0;
667 if (parent == NULL) {
668 unsigned int i, num_q, ingress;
670 ingress = 0;
671 num_q = dev->num_tx_queues;
672 if ((q && q->flags & TCQ_F_INGRESS) ||
673 (new && new->flags & TCQ_F_INGRESS)) {
674 num_q = 1;
675 ingress = 1;
678 if (dev->flags & IFF_UP)
679 dev_deactivate(dev);
681 if (new && new->ops->attach) {
682 new->ops->attach(new);
683 num_q = 0;
686 for (i = 0; i < num_q; i++) {
687 struct netdev_queue *dev_queue = &dev->rx_queue;
689 if (!ingress)
690 dev_queue = netdev_get_tx_queue(dev, i);
692 old = dev_graft_qdisc(dev_queue, new);
693 if (new && i > 0)
694 atomic_inc(&new->refcnt);
696 if (!ingress)
697 qdisc_destroy(old);
700 if (!ingress) {
701 notify_and_destroy(skb, n, classid, dev->qdisc, new);
702 if (new && !new->ops->attach)
703 atomic_inc(&new->refcnt);
704 dev->qdisc = new ? : &noop_qdisc;
705 } else {
706 notify_and_destroy(skb, n, classid, old, new);
709 if (dev->flags & IFF_UP)
710 dev_activate(dev);
711 } else {
712 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
714 err = -EOPNOTSUPP;
715 if (cops && cops->graft) {
716 unsigned long cl = cops->get(parent, classid);
717 if (cl) {
718 err = cops->graft(parent, cl, new, &old);
719 cops->put(parent, cl);
720 } else
721 err = -ENOENT;
723 if (!err)
724 notify_and_destroy(skb, n, classid, old, new);
726 return err;
729 /* lockdep annotation is needed for ingress; egress gets it only for name */
730 static struct lock_class_key qdisc_tx_lock;
731 static struct lock_class_key qdisc_rx_lock;
734 Allocate and initialize new qdisc.
736 Parameters are passed via opt.
739 static struct Qdisc *
740 qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue,
741 struct Qdisc *p, u32 parent, u32 handle,
742 struct nlattr **tca, int *errp)
744 int err;
745 struct nlattr *kind = tca[TCA_KIND];
746 struct Qdisc *sch;
747 struct Qdisc_ops *ops;
748 struct qdisc_size_table *stab;
750 ops = qdisc_lookup_ops(kind);
751 #ifdef CONFIG_MODULES
752 if (ops == NULL && kind != NULL) {
753 char name[IFNAMSIZ];
754 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) {
755 /* We dropped the RTNL semaphore in order to
756 * perform the module load. So, even if we
757 * succeeded in loading the module we have to
758 * tell the caller to replay the request. We
759 * indicate this using -EAGAIN.
760 * We replay the request because the device may
761 * go away in the mean time.
763 rtnl_unlock();
764 request_module("sch_%s", name);
765 rtnl_lock();
766 ops = qdisc_lookup_ops(kind);
767 if (ops != NULL) {
768 /* We will try again qdisc_lookup_ops,
769 * so don't keep a reference.
771 module_put(ops->owner);
772 err = -EAGAIN;
773 goto err_out;
777 #endif
779 err = -ENOENT;
780 if (ops == NULL)
781 goto err_out;
783 sch = qdisc_alloc(dev_queue, ops);
784 if (IS_ERR(sch)) {
785 err = PTR_ERR(sch);
786 goto err_out2;
789 sch->parent = parent;
791 if (handle == TC_H_INGRESS) {
792 sch->flags |= TCQ_F_INGRESS;
793 handle = TC_H_MAKE(TC_H_INGRESS, 0);
794 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock);
795 } else {
796 if (handle == 0) {
797 handle = qdisc_alloc_handle(dev);
798 err = -ENOMEM;
799 if (handle == 0)
800 goto err_out3;
802 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
805 sch->handle = handle;
807 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) {
808 if (tca[TCA_STAB]) {
809 stab = qdisc_get_stab(tca[TCA_STAB]);
810 if (IS_ERR(stab)) {
811 err = PTR_ERR(stab);
812 goto err_out4;
814 sch->stab = stab;
816 if (tca[TCA_RATE]) {
817 spinlock_t *root_lock;
819 err = -EOPNOTSUPP;
820 if (sch->flags & TCQ_F_MQROOT)
821 goto err_out4;
823 if ((sch->parent != TC_H_ROOT) &&
824 !(sch->flags & TCQ_F_INGRESS) &&
825 (!p || !(p->flags & TCQ_F_MQROOT)))
826 root_lock = qdisc_root_sleeping_lock(sch);
827 else
828 root_lock = qdisc_lock(sch);
830 err = gen_new_estimator(&sch->bstats, &sch->rate_est,
831 root_lock, tca[TCA_RATE]);
832 if (err)
833 goto err_out4;
836 qdisc_list_add(sch);
838 return sch;
840 err_out3:
841 dev_put(dev);
842 kfree((char *) sch - sch->padded);
843 err_out2:
844 module_put(ops->owner);
845 err_out:
846 *errp = err;
847 return NULL;
849 err_out4:
851 * Any broken qdiscs that would require a ops->reset() here?
852 * The qdisc was never in action so it shouldn't be necessary.
854 qdisc_put_stab(sch->stab);
855 if (ops->destroy)
856 ops->destroy(sch);
857 goto err_out3;
860 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
862 struct qdisc_size_table *stab = NULL;
863 int err = 0;
865 if (tca[TCA_OPTIONS]) {
866 if (sch->ops->change == NULL)
867 return -EINVAL;
868 err = sch->ops->change(sch, tca[TCA_OPTIONS]);
869 if (err)
870 return err;
873 if (tca[TCA_STAB]) {
874 stab = qdisc_get_stab(tca[TCA_STAB]);
875 if (IS_ERR(stab))
876 return PTR_ERR(stab);
879 qdisc_put_stab(sch->stab);
880 sch->stab = stab;
882 if (tca[TCA_RATE]) {
883 /* NB: ignores errors from replace_estimator
884 because change can't be undone. */
885 if (sch->flags & TCQ_F_MQROOT)
886 goto out;
887 gen_replace_estimator(&sch->bstats, &sch->rate_est,
888 qdisc_root_sleeping_lock(sch),
889 tca[TCA_RATE]);
891 out:
892 return 0;
895 struct check_loop_arg
897 struct qdisc_walker w;
898 struct Qdisc *p;
899 int depth;
902 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
904 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
906 struct check_loop_arg arg;
908 if (q->ops->cl_ops == NULL)
909 return 0;
911 arg.w.stop = arg.w.skip = arg.w.count = 0;
912 arg.w.fn = check_loop_fn;
913 arg.depth = depth;
914 arg.p = p;
915 q->ops->cl_ops->walk(q, &arg.w);
916 return arg.w.stop ? -ELOOP : 0;
919 static int
920 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
922 struct Qdisc *leaf;
923 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
924 struct check_loop_arg *arg = (struct check_loop_arg *)w;
926 leaf = cops->leaf(q, cl);
927 if (leaf) {
928 if (leaf == arg->p || arg->depth > 7)
929 return -ELOOP;
930 return check_loop(leaf, arg->p, arg->depth + 1);
932 return 0;
936 * Delete/get qdisc.
939 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
941 struct net *net = sock_net(skb->sk);
942 struct tcmsg *tcm = NLMSG_DATA(n);
943 struct nlattr *tca[TCA_MAX + 1];
944 struct net_device *dev;
945 u32 clid = tcm->tcm_parent;
946 struct Qdisc *q = NULL;
947 struct Qdisc *p = NULL;
948 int err;
950 if (net != &init_net)
951 return -EINVAL;
953 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
954 return -ENODEV;
956 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
957 if (err < 0)
958 return err;
960 if (clid) {
961 if (clid != TC_H_ROOT) {
962 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) {
963 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL)
964 return -ENOENT;
965 q = qdisc_leaf(p, clid);
966 } else { /* ingress */
967 q = dev->rx_queue.qdisc_sleeping;
969 } else {
970 q = dev->qdisc;
972 if (!q)
973 return -ENOENT;
975 if (tcm->tcm_handle && q->handle != tcm->tcm_handle)
976 return -EINVAL;
977 } else {
978 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL)
979 return -ENOENT;
982 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
983 return -EINVAL;
985 if (n->nlmsg_type == RTM_DELQDISC) {
986 if (!clid)
987 return -EINVAL;
988 if (q->handle == 0)
989 return -ENOENT;
990 if ((err = qdisc_graft(dev, p, skb, n, clid, NULL, q)) != 0)
991 return err;
992 } else {
993 qdisc_notify(skb, n, clid, NULL, q);
995 return 0;
999 Create/change qdisc.
1002 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1004 struct net *net = sock_net(skb->sk);
1005 struct tcmsg *tcm;
1006 struct nlattr *tca[TCA_MAX + 1];
1007 struct net_device *dev;
1008 u32 clid;
1009 struct Qdisc *q, *p;
1010 int err;
1012 if (net != &init_net)
1013 return -EINVAL;
1015 replay:
1016 /* Reinit, just in case something touches this. */
1017 tcm = NLMSG_DATA(n);
1018 clid = tcm->tcm_parent;
1019 q = p = NULL;
1021 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1022 return -ENODEV;
1024 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1025 if (err < 0)
1026 return err;
1028 if (clid) {
1029 if (clid != TC_H_ROOT) {
1030 if (clid != TC_H_INGRESS) {
1031 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL)
1032 return -ENOENT;
1033 q = qdisc_leaf(p, clid);
1034 } else { /*ingress */
1035 q = dev->rx_queue.qdisc_sleeping;
1037 } else {
1038 q = dev->qdisc;
1041 /* It may be default qdisc, ignore it */
1042 if (q && q->handle == 0)
1043 q = NULL;
1045 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) {
1046 if (tcm->tcm_handle) {
1047 if (q && !(n->nlmsg_flags&NLM_F_REPLACE))
1048 return -EEXIST;
1049 if (TC_H_MIN(tcm->tcm_handle))
1050 return -EINVAL;
1051 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL)
1052 goto create_n_graft;
1053 if (n->nlmsg_flags&NLM_F_EXCL)
1054 return -EEXIST;
1055 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1056 return -EINVAL;
1057 if (q == p ||
1058 (p && check_loop(q, p, 0)))
1059 return -ELOOP;
1060 atomic_inc(&q->refcnt);
1061 goto graft;
1062 } else {
1063 if (q == NULL)
1064 goto create_n_graft;
1066 /* This magic test requires explanation.
1068 * We know, that some child q is already
1069 * attached to this parent and have choice:
1070 * either to change it or to create/graft new one.
1072 * 1. We are allowed to create/graft only
1073 * if CREATE and REPLACE flags are set.
1075 * 2. If EXCL is set, requestor wanted to say,
1076 * that qdisc tcm_handle is not expected
1077 * to exist, so that we choose create/graft too.
1079 * 3. The last case is when no flags are set.
1080 * Alas, it is sort of hole in API, we
1081 * cannot decide what to do unambiguously.
1082 * For now we select create/graft, if
1083 * user gave KIND, which does not match existing.
1085 if ((n->nlmsg_flags&NLM_F_CREATE) &&
1086 (n->nlmsg_flags&NLM_F_REPLACE) &&
1087 ((n->nlmsg_flags&NLM_F_EXCL) ||
1088 (tca[TCA_KIND] &&
1089 nla_strcmp(tca[TCA_KIND], q->ops->id))))
1090 goto create_n_graft;
1093 } else {
1094 if (!tcm->tcm_handle)
1095 return -EINVAL;
1096 q = qdisc_lookup(dev, tcm->tcm_handle);
1099 /* Change qdisc parameters */
1100 if (q == NULL)
1101 return -ENOENT;
1102 if (n->nlmsg_flags&NLM_F_EXCL)
1103 return -EEXIST;
1104 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
1105 return -EINVAL;
1106 err = qdisc_change(q, tca);
1107 if (err == 0)
1108 qdisc_notify(skb, n, clid, NULL, q);
1109 return err;
1111 create_n_graft:
1112 if (!(n->nlmsg_flags&NLM_F_CREATE))
1113 return -ENOENT;
1114 if (clid == TC_H_INGRESS)
1115 q = qdisc_create(dev, &dev->rx_queue, p,
1116 tcm->tcm_parent, tcm->tcm_parent,
1117 tca, &err);
1118 else {
1119 struct netdev_queue *dev_queue;
1121 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue)
1122 dev_queue = p->ops->cl_ops->select_queue(p, tcm);
1123 else if (p)
1124 dev_queue = p->dev_queue;
1125 else
1126 dev_queue = netdev_get_tx_queue(dev, 0);
1128 q = qdisc_create(dev, dev_queue, p,
1129 tcm->tcm_parent, tcm->tcm_handle,
1130 tca, &err);
1132 if (q == NULL) {
1133 if (err == -EAGAIN)
1134 goto replay;
1135 return err;
1138 graft:
1139 err = qdisc_graft(dev, p, skb, n, clid, q, NULL);
1140 if (err) {
1141 if (q)
1142 qdisc_destroy(q);
1143 return err;
1146 return 0;
1149 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1150 u32 pid, u32 seq, u16 flags, int event)
1152 struct tcmsg *tcm;
1153 struct nlmsghdr *nlh;
1154 unsigned char *b = skb_tail_pointer(skb);
1155 struct gnet_dump d;
1157 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
1158 tcm = NLMSG_DATA(nlh);
1159 tcm->tcm_family = AF_UNSPEC;
1160 tcm->tcm__pad1 = 0;
1161 tcm->tcm__pad2 = 0;
1162 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1163 tcm->tcm_parent = clid;
1164 tcm->tcm_handle = q->handle;
1165 tcm->tcm_info = atomic_read(&q->refcnt);
1166 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id);
1167 if (q->ops->dump && q->ops->dump(q, skb) < 0)
1168 goto nla_put_failure;
1169 q->qstats.qlen = q->q.qlen;
1171 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0)
1172 goto nla_put_failure;
1174 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1175 qdisc_root_sleeping_lock(q), &d) < 0)
1176 goto nla_put_failure;
1178 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1179 goto nla_put_failure;
1181 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
1182 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 ||
1183 gnet_stats_copy_queue(&d, &q->qstats) < 0)
1184 goto nla_put_failure;
1186 if (gnet_stats_finish_copy(&d) < 0)
1187 goto nla_put_failure;
1189 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1190 return skb->len;
1192 nlmsg_failure:
1193 nla_put_failure:
1194 nlmsg_trim(skb, b);
1195 return -1;
1198 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n,
1199 u32 clid, struct Qdisc *old, struct Qdisc *new)
1201 struct sk_buff *skb;
1202 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1204 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1205 if (!skb)
1206 return -ENOBUFS;
1208 if (old && old->handle) {
1209 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0)
1210 goto err_out;
1212 if (new) {
1213 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
1214 goto err_out;
1217 if (skb->len)
1218 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
1220 err_out:
1221 kfree_skb(skb);
1222 return -EINVAL;
1225 static bool tc_qdisc_dump_ignore(struct Qdisc *q)
1227 return (q->flags & TCQ_F_BUILTIN) ? true : false;
1230 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
1231 struct netlink_callback *cb,
1232 int *q_idx_p, int s_q_idx)
1234 int ret = 0, q_idx = *q_idx_p;
1235 struct Qdisc *q;
1237 if (!root)
1238 return 0;
1240 q = root;
1241 if (q_idx < s_q_idx) {
1242 q_idx++;
1243 } else {
1244 if (!tc_qdisc_dump_ignore(q) &&
1245 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid,
1246 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1247 goto done;
1248 q_idx++;
1250 list_for_each_entry(q, &root->list, list) {
1251 if (q_idx < s_q_idx) {
1252 q_idx++;
1253 continue;
1255 if (!tc_qdisc_dump_ignore(q) &&
1256 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid,
1257 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0)
1258 goto done;
1259 q_idx++;
1262 out:
1263 *q_idx_p = q_idx;
1264 return ret;
1265 done:
1266 ret = -1;
1267 goto out;
1270 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1272 struct net *net = sock_net(skb->sk);
1273 int idx, q_idx;
1274 int s_idx, s_q_idx;
1275 struct net_device *dev;
1277 if (net != &init_net)
1278 return 0;
1280 s_idx = cb->args[0];
1281 s_q_idx = q_idx = cb->args[1];
1282 read_lock(&dev_base_lock);
1283 idx = 0;
1284 for_each_netdev(&init_net, dev) {
1285 struct netdev_queue *dev_queue;
1287 if (idx < s_idx)
1288 goto cont;
1289 if (idx > s_idx)
1290 s_q_idx = 0;
1291 q_idx = 0;
1293 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1294 goto done;
1296 dev_queue = &dev->rx_queue;
1297 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0)
1298 goto done;
1300 cont:
1301 idx++;
1304 done:
1305 read_unlock(&dev_base_lock);
1307 cb->args[0] = idx;
1308 cb->args[1] = q_idx;
1310 return skb->len;
1315 /************************************************
1316 * Traffic classes manipulation. *
1317 ************************************************/
1321 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1323 struct net *net = sock_net(skb->sk);
1324 struct tcmsg *tcm = NLMSG_DATA(n);
1325 struct nlattr *tca[TCA_MAX + 1];
1326 struct net_device *dev;
1327 struct Qdisc *q = NULL;
1328 const struct Qdisc_class_ops *cops;
1329 unsigned long cl = 0;
1330 unsigned long new_cl;
1331 u32 pid = tcm->tcm_parent;
1332 u32 clid = tcm->tcm_handle;
1333 u32 qid = TC_H_MAJ(clid);
1334 int err;
1336 if (net != &init_net)
1337 return -EINVAL;
1339 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1340 return -ENODEV;
1342 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1343 if (err < 0)
1344 return err;
1347 parent == TC_H_UNSPEC - unspecified parent.
1348 parent == TC_H_ROOT - class is root, which has no parent.
1349 parent == X:0 - parent is root class.
1350 parent == X:Y - parent is a node in hierarchy.
1351 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
1353 handle == 0:0 - generate handle from kernel pool.
1354 handle == 0:Y - class is X:Y, where X:0 is qdisc.
1355 handle == X:Y - clear.
1356 handle == X:0 - root class.
1359 /* Step 1. Determine qdisc handle X:0 */
1361 if (pid != TC_H_ROOT) {
1362 u32 qid1 = TC_H_MAJ(pid);
1364 if (qid && qid1) {
1365 /* If both majors are known, they must be identical. */
1366 if (qid != qid1)
1367 return -EINVAL;
1368 } else if (qid1) {
1369 qid = qid1;
1370 } else if (qid == 0)
1371 qid = dev->qdisc->handle;
1373 /* Now qid is genuine qdisc handle consistent
1374 both with parent and child.
1376 TC_H_MAJ(pid) still may be unspecified, complete it now.
1378 if (pid)
1379 pid = TC_H_MAKE(qid, pid);
1380 } else {
1381 if (qid == 0)
1382 qid = dev->qdisc->handle;
1385 /* OK. Locate qdisc */
1386 if ((q = qdisc_lookup(dev, qid)) == NULL)
1387 return -ENOENT;
1389 /* An check that it supports classes */
1390 cops = q->ops->cl_ops;
1391 if (cops == NULL)
1392 return -EINVAL;
1394 /* Now try to get class */
1395 if (clid == 0) {
1396 if (pid == TC_H_ROOT)
1397 clid = qid;
1398 } else
1399 clid = TC_H_MAKE(qid, clid);
1401 if (clid)
1402 cl = cops->get(q, clid);
1404 if (cl == 0) {
1405 err = -ENOENT;
1406 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE))
1407 goto out;
1408 } else {
1409 switch (n->nlmsg_type) {
1410 case RTM_NEWTCLASS:
1411 err = -EEXIST;
1412 if (n->nlmsg_flags&NLM_F_EXCL)
1413 goto out;
1414 break;
1415 case RTM_DELTCLASS:
1416 err = -EOPNOTSUPP;
1417 if (cops->delete)
1418 err = cops->delete(q, cl);
1419 if (err == 0)
1420 tclass_notify(skb, n, q, cl, RTM_DELTCLASS);
1421 goto out;
1422 case RTM_GETTCLASS:
1423 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS);
1424 goto out;
1425 default:
1426 err = -EINVAL;
1427 goto out;
1431 new_cl = cl;
1432 err = -EOPNOTSUPP;
1433 if (cops->change)
1434 err = cops->change(q, clid, pid, tca, &new_cl);
1435 if (err == 0)
1436 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS);
1438 out:
1439 if (cl)
1440 cops->put(q, cl);
1442 return err;
1446 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1447 unsigned long cl,
1448 u32 pid, u32 seq, u16 flags, int event)
1450 struct tcmsg *tcm;
1451 struct nlmsghdr *nlh;
1452 unsigned char *b = skb_tail_pointer(skb);
1453 struct gnet_dump d;
1454 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1456 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
1457 tcm = NLMSG_DATA(nlh);
1458 tcm->tcm_family = AF_UNSPEC;
1459 tcm->tcm__pad1 = 0;
1460 tcm->tcm__pad2 = 0;
1461 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1462 tcm->tcm_parent = q->handle;
1463 tcm->tcm_handle = q->handle;
1464 tcm->tcm_info = 0;
1465 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id);
1466 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1467 goto nla_put_failure;
1469 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1470 qdisc_root_sleeping_lock(q), &d) < 0)
1471 goto nla_put_failure;
1473 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1474 goto nla_put_failure;
1476 if (gnet_stats_finish_copy(&d) < 0)
1477 goto nla_put_failure;
1479 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1480 return skb->len;
1482 nlmsg_failure:
1483 nla_put_failure:
1484 nlmsg_trim(skb, b);
1485 return -1;
1488 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n,
1489 struct Qdisc *q, unsigned long cl, int event)
1491 struct sk_buff *skb;
1492 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1494 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1495 if (!skb)
1496 return -ENOBUFS;
1498 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) {
1499 kfree_skb(skb);
1500 return -EINVAL;
1503 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
1506 struct qdisc_dump_args
1508 struct qdisc_walker w;
1509 struct sk_buff *skb;
1510 struct netlink_callback *cb;
1513 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
1515 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
1517 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid,
1518 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
1521 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
1522 struct tcmsg *tcm, struct netlink_callback *cb,
1523 int *t_p, int s_t)
1525 struct qdisc_dump_args arg;
1527 if (tc_qdisc_dump_ignore(q) ||
1528 *t_p < s_t || !q->ops->cl_ops ||
1529 (tcm->tcm_parent &&
1530 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
1531 (*t_p)++;
1532 return 0;
1534 if (*t_p > s_t)
1535 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
1536 arg.w.fn = qdisc_class_dump;
1537 arg.skb = skb;
1538 arg.cb = cb;
1539 arg.w.stop = 0;
1540 arg.w.skip = cb->args[1];
1541 arg.w.count = 0;
1542 q->ops->cl_ops->walk(q, &arg.w);
1543 cb->args[1] = arg.w.count;
1544 if (arg.w.stop)
1545 return -1;
1546 (*t_p)++;
1547 return 0;
1550 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
1551 struct tcmsg *tcm, struct netlink_callback *cb,
1552 int *t_p, int s_t)
1554 struct Qdisc *q;
1556 if (!root)
1557 return 0;
1559 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
1560 return -1;
1562 list_for_each_entry(q, &root->list, list) {
1563 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
1564 return -1;
1567 return 0;
1570 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
1572 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh);
1573 struct net *net = sock_net(skb->sk);
1574 struct netdev_queue *dev_queue;
1575 struct net_device *dev;
1576 int t, s_t;
1578 if (net != &init_net)
1579 return 0;
1581 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
1582 return 0;
1583 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1584 return 0;
1586 s_t = cb->args[0];
1587 t = 0;
1589 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1590 goto done;
1592 dev_queue = &dev->rx_queue;
1593 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0)
1594 goto done;
1596 done:
1597 cb->args[0] = t;
1599 dev_put(dev);
1600 return skb->len;
1603 /* Main classifier routine: scans classifier chain attached
1604 to this qdisc, (optionally) tests for protocol and asks
1605 specific classifiers.
1607 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,
1608 struct tcf_result *res)
1610 __be16 protocol = skb->protocol;
1611 int err = 0;
1613 for (; tp; tp = tp->next) {
1614 if ((tp->protocol == protocol ||
1615 tp->protocol == htons(ETH_P_ALL)) &&
1616 (err = tp->classify(skb, tp, res)) >= 0) {
1617 #ifdef CONFIG_NET_CLS_ACT
1618 if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
1619 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
1620 #endif
1621 return err;
1624 return -1;
1626 EXPORT_SYMBOL(tc_classify_compat);
1628 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
1629 struct tcf_result *res)
1631 int err = 0;
1632 __be16 protocol;
1633 #ifdef CONFIG_NET_CLS_ACT
1634 struct tcf_proto *otp = tp;
1635 reclassify:
1636 #endif
1637 protocol = skb->protocol;
1639 err = tc_classify_compat(skb, tp, res);
1640 #ifdef CONFIG_NET_CLS_ACT
1641 if (err == TC_ACT_RECLASSIFY) {
1642 u32 verd = G_TC_VERD(skb->tc_verd);
1643 tp = otp;
1645 if (verd++ >= MAX_REC_LOOP) {
1646 printk("rule prio %u protocol %02x reclassify loop, "
1647 "packet dropped\n",
1648 tp->prio&0xffff, ntohs(tp->protocol));
1649 return TC_ACT_SHOT;
1651 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
1652 goto reclassify;
1654 #endif
1655 return err;
1657 EXPORT_SYMBOL(tc_classify);
1659 void tcf_destroy(struct tcf_proto *tp)
1661 tp->ops->destroy(tp);
1662 module_put(tp->ops->owner);
1663 kfree(tp);
1666 void tcf_destroy_chain(struct tcf_proto **fl)
1668 struct tcf_proto *tp;
1670 while ((tp = *fl) != NULL) {
1671 *fl = tp->next;
1672 tcf_destroy(tp);
1675 EXPORT_SYMBOL(tcf_destroy_chain);
1677 #ifdef CONFIG_PROC_FS
1678 static int psched_show(struct seq_file *seq, void *v)
1680 struct timespec ts;
1682 hrtimer_get_res(CLOCK_MONOTONIC, &ts);
1683 seq_printf(seq, "%08x %08x %08x %08x\n",
1684 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1685 1000000,
1686 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
1688 return 0;
1691 static int psched_open(struct inode *inode, struct file *file)
1693 return single_open(file, psched_show, PDE(inode)->data);
1696 static const struct file_operations psched_fops = {
1697 .owner = THIS_MODULE,
1698 .open = psched_open,
1699 .read = seq_read,
1700 .llseek = seq_lseek,
1701 .release = single_release,
1703 #endif
1705 static int __init pktsched_init(void)
1707 register_qdisc(&pfifo_qdisc_ops);
1708 register_qdisc(&bfifo_qdisc_ops);
1709 register_qdisc(&mq_qdisc_ops);
1710 proc_net_fops_create(&init_net, "psched", 0, &psched_fops);
1712 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL);
1713 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL);
1714 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc);
1715 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL);
1716 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL);
1717 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass);
1719 return 0;
1722 subsys_initcall(pktsched_init);