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Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / sched / sch_api.c
blob6cd491013b503f264fe210545a118f45cb8df0d0
1 /*
2 * net/sched/sch_api.c Packet scheduler API.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 * Fixes:
12 *
13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired.
14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support
16 */
17
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/errno.h>
23 #include <linux/skbuff.h>
24 #include <linux/init.h>
25 #include <linux/proc_fs.h>
26 #include <linux/seq_file.h>
27 #include <linux/kmod.h>
28 #include <linux/list.h>
29 #include <linux/hrtimer.h>
30 #include <linux/lockdep.h>
31
32 #include <net/net_namespace.h>
33 #include <net/sock.h>
34 #include <net/netlink.h>
35 #include <net/pkt_sched.h>
36
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);
41
42 /*
43
44 Short review.
45 -------------
46
47 This file consists of two interrelated parts:
48
49 1. queueing disciplines manager frontend.
50 2. traffic classes manager frontend.
51
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.
56
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)
61
62 In turn, classes may have child qdiscs (as rule, queues)
63 attached to them etc. etc. etc.
64
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.
70
71 All real intelligent work is done inside qdisc modules.
72
73
74
75 Every discipline has two major routines: enqueue and dequeue.
76
77 ---dequeue
78
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.
85
86 ---enqueue
87
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.
97
98 Auxiliary routines:
99
100 ---peek
101
102 like dequeue but without removing a packet from the queue
103
104 ---reset
105
106 returns qdisc to initial state: purge all buffers, clear all
107 timers, counters (except for statistics) etc.
108
109 ---init
110
111 initializes newly created qdisc.
112
113 ---destroy
114
115 destroys resources allocated by init and during lifetime of qdisc.
116
117 ---change
118
119 changes qdisc parameters.
120 */
121
122 /* Protects list of registered TC modules. It is pure SMP lock. */
123 static DEFINE_RWLOCK(qdisc_mod_lock);
124
125
126 /************************************************
127 * Queueing disciplines manipulation. *
128 ************************************************/
129
130
131 /* The list of all installed queueing disciplines. */
132
133 static struct Qdisc_ops *qdisc_base;
134
135 /* Register/uregister queueing discipline */
136
137 int register_qdisc(struct Qdisc_ops *qops)
138 {
139 struct Qdisc_ops *q, **qp;
140 int rc = -EEXIST;
141
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;
146
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;
155 }
156 }
157 if (qops->dequeue == NULL)
158 qops->dequeue = noop_qdisc_ops.dequeue;
159
160 qops->next = NULL;
161 *qp = qops;
162 rc = 0;
163 out:
164 write_unlock(&qdisc_mod_lock);
165 return rc;
166 }
167 EXPORT_SYMBOL(register_qdisc);
168
169 int unregister_qdisc(struct Qdisc_ops *qops)
170 {
171 struct Qdisc_ops *q, **qp;
172 int err = -ENOENT;
173
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;
182 }
183 write_unlock(&qdisc_mod_lock);
184 return err;
185 }
186 EXPORT_SYMBOL(unregister_qdisc);
187
188 /* We know handle. Find qdisc among all qdisc's attached to device
189 (root qdisc, all its children, children of children etc.)
190 */
191
192 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle)
193 {
194 struct Qdisc *q;
195
196 if (!(root->flags & TCQ_F_BUILTIN) &&
197 root->handle == handle)
198 return root;
199
200 list_for_each_entry(q, &root->list, list) {
201 if (q->handle == handle)
202 return q;
203 }
204 return NULL;
205 }
206
207 static void qdisc_list_add(struct Qdisc *q)
208 {
209 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
210 list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list);
211 }
212
213 void qdisc_list_del(struct Qdisc *q)
214 {
215 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS))
216 list_del(&q->list);
217 }
218 EXPORT_SYMBOL(qdisc_list_del);
219
220 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle)
221 {
222 struct Qdisc *q;
223
224 q = qdisc_match_from_root(dev->qdisc, handle);
225 if (q)
226 goto out;
227
228 q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle);
229 out:
230 return q;
231 }
232
233 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid)
234 {
235 unsigned long cl;
236 struct Qdisc *leaf;
237 const struct Qdisc_class_ops *cops = p->ops->cl_ops;
238
239 if (cops == NULL)
240 return NULL;
241 cl = cops->get(p, classid);
242
243 if (cl == 0)
244 return NULL;
245 leaf = cops->leaf(p, cl);
246 cops->put(p, cl);
247 return leaf;
248 }
249
250 /* Find queueing discipline by name */
251
252 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind)
253 {
254 struct Qdisc_ops *q = NULL;
255
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;
263 }
264 }
265 read_unlock(&qdisc_mod_lock);
266 }
267 return q;
268 }
269
270 static struct qdisc_rate_table *qdisc_rtab_list;
271
272 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab)
273 {
274 struct qdisc_rate_table *rtab;
275
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;
280 }
281 }
282
283 if (tab == NULL || r->rate == 0 || r->cell_log == 0 ||
284 nla_len(tab) != TC_RTAB_SIZE)
285 return NULL;
286
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;
294 }
295 return rtab;
296 }
297 EXPORT_SYMBOL(qdisc_get_rtab);
298
299 void qdisc_put_rtab(struct qdisc_rate_table *tab)
300 {
301 struct qdisc_rate_table *rtab, **rtabp;
302
303 if (!tab || --tab->refcnt)
304 return;
305
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;
311 }
312 }
313 }
314 EXPORT_SYMBOL(qdisc_put_rtab);
315
316 static LIST_HEAD(qdisc_stab_list);
317 static DEFINE_SPINLOCK(qdisc_stab_lock);
318
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 },
322 };
323
324 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
325 {
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;
332
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);
338
339 s = nla_data(tb[TCA_STAB_BASE]);
340
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);
346 }
347
348 if (!s || tsize != s->tsize || (!tab && tsize > 0))
349 return ERR_PTR(-EINVAL);
350
351 spin_lock(&qdisc_stab_lock);
352
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;
361 }
362
363 spin_unlock(&qdisc_stab_lock);
364
365 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL);
366 if (!stab)
367 return ERR_PTR(-ENOMEM);
368
369 stab->refcnt = 1;
370 stab->szopts = *s;
371 if (tsize > 0)
372 memcpy(stab->data, tab, tsize * sizeof(u16));
373
374 spin_lock(&qdisc_stab_lock);
375 list_add_tail(&stab->list, &qdisc_stab_list);
376 spin_unlock(&qdisc_stab_lock);
377
378 return stab;
379 }
380
381 void qdisc_put_stab(struct qdisc_size_table *tab)
382 {
383 if (!tab)
384 return;
385
386 spin_lock(&qdisc_stab_lock);
387
388 if (--tab->refcnt == 0) {
389 list_del(&tab->list);
390 kfree(tab);
391 }
392
393 spin_unlock(&qdisc_stab_lock);
394 }
395 EXPORT_SYMBOL(qdisc_put_stab);
396
397 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab)
398 {
399 struct nlattr *nest;
400
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);
406
407 return skb->len;
408
409 nla_put_failure:
410 return -1;
411 }
412
413 void qdisc_calculate_pkt_len(struct sk_buff *skb, struct qdisc_size_table *stab)
414 {
415 int pkt_len, slot;
416
417 pkt_len = skb->len + stab->szopts.overhead;
418 if (unlikely(!stab->szopts.tsize))
419 goto out;
420
421 slot = pkt_len + stab->szopts.cell_align;
422 if (unlikely(slot < 0))
423 slot = 0;
424
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];
432
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;
438 }
439 EXPORT_SYMBOL(qdisc_calculate_pkt_len);
440
441 void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc)
442 {
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;
448 }
449 }
450 EXPORT_SYMBOL(qdisc_warn_nonwc);
451
452 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
453 {
454 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
455 timer);
456
457 wd->qdisc->flags &= ~TCQ_F_THROTTLED;
458 __netif_schedule(qdisc_root(wd->qdisc));
459
460 return HRTIMER_NORESTART;
461 }
462
463 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
464 {
465 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
466 wd->timer.function = qdisc_watchdog;
467 wd->qdisc = qdisc;
468 }
469 EXPORT_SYMBOL(qdisc_watchdog_init);
470
471 void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires)
472 {
473 ktime_t time;
474
475 if (test_bit(__QDISC_STATE_DEACTIVATED,
476 &qdisc_root_sleeping(wd->qdisc)->state))
477 return;
478
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);
483 }
484 EXPORT_SYMBOL(qdisc_watchdog_schedule);
485
486 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
487 {
488 hrtimer_cancel(&wd->timer);
489 wd->qdisc->flags &= ~TCQ_F_THROTTLED;
490 }
491 EXPORT_SYMBOL(qdisc_watchdog_cancel);
492
493 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n)
494 {
495 unsigned int size = n * sizeof(struct hlist_head), i;
496 struct hlist_head *h;
497
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));
503
504 if (h != NULL) {
505 for (i = 0; i < n; i++)
506 INIT_HLIST_HEAD(&h[i]);
507 }
508 return h;
509 }
510
511 static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n)
512 {
513 unsigned int size = n * sizeof(struct hlist_head);
514
515 if (size <= PAGE_SIZE)
516 kfree(h);
517 else
518 free_pages((unsigned long)h, get_order(size));
519 }
520
521 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash)
522 {
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;
528
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;
537
538 ohash = clhash->hash;
539 osize = clhash->hashsize;
540
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]);
546 }
547 }
548 clhash->hash = nhash;
549 clhash->hashsize = nsize;
550 clhash->hashmask = nmask;
551 sch_tree_unlock(sch);
552
553 qdisc_class_hash_free(ohash, osize);
554 }
555 EXPORT_SYMBOL(qdisc_class_hash_grow);
556
557 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash)
558 {
559 unsigned int size = 4;
560
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;
568 }
569 EXPORT_SYMBOL(qdisc_class_hash_init);
570
571 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash)
572 {
573 qdisc_class_hash_free(clhash->hash, clhash->hashsize);
574 }
575 EXPORT_SYMBOL(qdisc_class_hash_destroy);
576
577 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash,
578 struct Qdisc_class_common *cl)
579 {
580 unsigned int h;
581
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++;
586 }
587 EXPORT_SYMBOL(qdisc_class_hash_insert);
588
589 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash,
590 struct Qdisc_class_common *cl)
591 {
592 hlist_del(&cl->hnode);
593 clhash->hashelems--;
594 }
595 EXPORT_SYMBOL(qdisc_class_hash_remove);
596
597 /* Allocate an unique handle from space managed by kernel */
598
599 static u32 qdisc_alloc_handle(struct net_device *dev)
600 {
601 int i = 0x10000;
602 static u32 autohandle = TC_H_MAKE(0x80000000U, 0);
603
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);
609
610 return i>0 ? autohandle : 0;
611 }
612
613 void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n)
614 {
615 const struct Qdisc_class_ops *cops;
616 unsigned long cl;
617 u32 parentid;
618
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;
624
625 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid));
626 if (sch == NULL) {
627 WARN_ON(parentid != TC_H_ROOT);
628 return;
629 }
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);
635 }
636 sch->q.qlen -= n;
637 }
638 }
639 EXPORT_SYMBOL(qdisc_tree_decrease_qlen);
640
641 static void notify_and_destroy(struct sk_buff *skb, struct nlmsghdr *n, u32 clid,
642 struct Qdisc *old, struct Qdisc *new)
643 {
644 if (new || old)
645 qdisc_notify(skb, n, clid, old, new);
646
647 if (old)
648 qdisc_destroy(old);
649 }
650
651 /* Graft qdisc "new" to class "classid" of qdisc "parent" or
652 * to device "dev".
653 *
654 * When appropriate send a netlink notification using 'skb'
655 * and "n".
656 *
657 * On success, destroy old qdisc.
658 */
659
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)
663 {
664 struct Qdisc *q = old;
665 int err = 0;
666
667 if (parent == NULL) {
668 unsigned int i, num_q, ingress;
669
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;
676 }
677
678 if (dev->flags & IFF_UP)
679 dev_deactivate(dev);
680
681 if (new && new->ops->attach) {
682 new->ops->attach(new);
683 num_q = 0;
684 }
685
686 for (i = 0; i < num_q; i++) {
687 struct netdev_queue *dev_queue = &dev->rx_queue;
688
689 if (!ingress)
690 dev_queue = netdev_get_tx_queue(dev, i);
691
692 old = dev_graft_qdisc(dev_queue, new);
693 if (new && i > 0)
694 atomic_inc(&new->refcnt);
695
696 if (!ingress)
697 qdisc_destroy(old);
698 }
699
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);
707 }
708
709 if (dev->flags & IFF_UP)
710 dev_activate(dev);
711 } else {
712 const struct Qdisc_class_ops *cops = parent->ops->cl_ops;
713
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;
722 }
723 if (!err)
724 notify_and_destroy(skb, n, classid, old, new);
725 }
726 return err;
727 }
728
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;
732
733 /*
734 Allocate and initialize new qdisc.
735
736 Parameters are passed via opt.
737 */
738
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)
743 {
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;
749
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.
762 */
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.
770 */
771 module_put(ops->owner);
772 err = -EAGAIN;
773 goto err_out;
774 }
775 }
776 }
777 #endif
778
779 err = -ENOENT;
780 if (ops == NULL)
781 goto err_out;
782
783 sch = qdisc_alloc(dev_queue, ops);
784 if (IS_ERR(sch)) {
785 err = PTR_ERR(sch);
786 goto err_out2;
787 }
788
789 sch->parent = parent;
790
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;
801 }
802 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock);
803 }
804
805 sch->handle = handle;
806
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;
813 }
814 sch->stab = stab;
815 }
816 if (tca[TCA_RATE]) {
817 spinlock_t *root_lock;
818
819 err = -EOPNOTSUPP;
820 if (sch->flags & TCQ_F_MQROOT)
821 goto err_out4;
822
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);
829
830 err = gen_new_estimator(&sch->bstats, &sch->rate_est,
831 root_lock, tca[TCA_RATE]);
832 if (err)
833 goto err_out4;
834 }
835
836 qdisc_list_add(sch);
837
838 return sch;
839 }
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;
848
849 err_out4:
850 /*
851 * Any broken qdiscs that would require a ops->reset() here?
852 * The qdisc was never in action so it shouldn't be necessary.
853 */
854 qdisc_put_stab(sch->stab);
855 if (ops->destroy)
856 ops->destroy(sch);
857 goto err_out3;
858 }
859
860 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca)
861 {
862 struct qdisc_size_table *stab = NULL;
863 int err = 0;
864
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;
871 }
872
873 if (tca[TCA_STAB]) {
874 stab = qdisc_get_stab(tca[TCA_STAB]);
875 if (IS_ERR(stab))
876 return PTR_ERR(stab);
877 }
878
879 qdisc_put_stab(sch->stab);
880 sch->stab = stab;
881
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]);
890 }
891 out:
892 return 0;
893 }
894
895 struct check_loop_arg
896 {
897 struct qdisc_walker w;
898 struct Qdisc *p;
899 int depth;
900 };
901
902 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w);
903
904 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth)
905 {
906 struct check_loop_arg arg;
907
908 if (q->ops->cl_ops == NULL)
909 return 0;
910
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;
917 }
918
919 static int
920 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w)
921 {
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;
925
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);
931 }
932 return 0;
933 }
934
935 /*
936 * Delete/get qdisc.
937 */
938
939 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
940 {
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;
949
950 if (!net_eq(net, &init_net))
951 return -EINVAL;
952
953 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
954 return -ENODEV;
955
956 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
957 if (err < 0)
958 return err;
959
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;
968 }
969 } else {
970 q = dev->qdisc;
971 }
972 if (!q)
973 return -ENOENT;
974
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;
980 }
981
982 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id))
983 return -EINVAL;
984
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);
994 }
995 return 0;
996 }
997
998 /*
999 Create/change qdisc.
1000 */
1001
1002 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1003 {
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;
1011
1012 if (!net_eq(net, &init_net))
1013 return -EINVAL;
1014
1015 replay:
1016 /* Reinit, just in case something touches this. */
1017 tcm = NLMSG_DATA(n);
1018 clid = tcm->tcm_parent;
1019 q = p = NULL;
1020
1021 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1022 return -ENODEV;
1023
1024 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1025 if (err < 0)
1026 return err;
1027
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;
1036 }
1037 } else {
1038 q = dev->qdisc;
1039 }
1040
1041 /* It may be default qdisc, ignore it */
1042 if (q && q->handle == 0)
1043 q = NULL;
1044
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;
1065
1066 /* This magic test requires explanation.
1067 *
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.
1071 *
1072 * 1. We are allowed to create/graft only
1073 * if CREATE and REPLACE flags are set.
1074 *
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.
1078 *
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.
1084 */
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;
1091 }
1092 }
1093 } else {
1094 if (!tcm->tcm_handle)
1095 return -EINVAL;
1096 q = qdisc_lookup(dev, tcm->tcm_handle);
1097 }
1098
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;
1110
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;
1120
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);
1127
1128 q = qdisc_create(dev, dev_queue, p,
1129 tcm->tcm_parent, tcm->tcm_handle,
1130 tca, &err);
1131 }
1132 if (q == NULL) {
1133 if (err == -EAGAIN)
1134 goto replay;
1135 return err;
1136 }
1137
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;
1144 }
1145
1146 return 0;
1147 }
1148
1149 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
1150 u32 pid, u32 seq, u16 flags, int event)
1151 {
1152 struct tcmsg *tcm;
1153 struct nlmsghdr *nlh;
1154 unsigned char *b = skb_tail_pointer(skb);
1155 struct gnet_dump d;
1156
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;
1170
1171 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0)
1172 goto nla_put_failure;
1173
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;
1177
1178 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0)
1179 goto nla_put_failure;
1180
1181 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 ||
1182 gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 ||
1183 gnet_stats_copy_queue(&d, &q->qstats) < 0)
1184 goto nla_put_failure;
1185
1186 if (gnet_stats_finish_copy(&d) < 0)
1187 goto nla_put_failure;
1188
1189 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1190 return skb->len;
1191
1192 nlmsg_failure:
1193 nla_put_failure:
1194 nlmsg_trim(skb, b);
1195 return -1;
1196 }
1197
1198 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n,
1199 u32 clid, struct Qdisc *old, struct Qdisc *new)
1200 {
1201 struct sk_buff *skb;
1202 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1203
1204 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1205 if (!skb)
1206 return -ENOBUFS;
1207
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;
1211 }
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;
1215 }
1216
1217 if (skb->len)
1218 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
1219
1220 err_out:
1221 kfree_skb(skb);
1222 return -EINVAL;
1223 }
1224
1225 static bool tc_qdisc_dump_ignore(struct Qdisc *q)
1226 {
1227 return (q->flags & TCQ_F_BUILTIN) ? true : false;
1228 }
1229
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)
1233 {
1234 int ret = 0, q_idx = *q_idx_p;
1235 struct Qdisc *q;
1236
1237 if (!root)
1238 return 0;
1239
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++;
1249 }
1250 list_for_each_entry(q, &root->list, list) {
1251 if (q_idx < s_q_idx) {
1252 q_idx++;
1253 continue;
1254 }
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++;
1260 }
1261
1262 out:
1263 *q_idx_p = q_idx;
1264 return ret;
1265 done:
1266 ret = -1;
1267 goto out;
1268 }
1269
1270 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb)
1271 {
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;
1276
1277 if (!net_eq(net, &init_net))
1278 return 0;
1279
1280 s_idx = cb->args[0];
1281 s_q_idx = q_idx = cb->args[1];
1282
1283 rcu_read_lock();
1284 idx = 0;
1285 for_each_netdev_rcu(&init_net, dev) {
1286 struct netdev_queue *dev_queue;
1287
1288 if (idx < s_idx)
1289 goto cont;
1290 if (idx > s_idx)
1291 s_q_idx = 0;
1292 q_idx = 0;
1293
1294 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0)
1295 goto done;
1296
1297 dev_queue = &dev->rx_queue;
1298 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0)
1299 goto done;
1300
1301 cont:
1302 idx++;
1303 }
1304
1305 done:
1306 rcu_read_unlock();
1307
1308 cb->args[0] = idx;
1309 cb->args[1] = q_idx;
1310
1311 return skb->len;
1312 }
1313
1314
1315
1316 /************************************************
1317 * Traffic classes manipulation. *
1318 ************************************************/
1319
1320
1321
1322 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
1323 {
1324 struct net *net = sock_net(skb->sk);
1325 struct tcmsg *tcm = NLMSG_DATA(n);
1326 struct nlattr *tca[TCA_MAX + 1];
1327 struct net_device *dev;
1328 struct Qdisc *q = NULL;
1329 const struct Qdisc_class_ops *cops;
1330 unsigned long cl = 0;
1331 unsigned long new_cl;
1332 u32 pid = tcm->tcm_parent;
1333 u32 clid = tcm->tcm_handle;
1334 u32 qid = TC_H_MAJ(clid);
1335 int err;
1336
1337 if (!net_eq(net, &init_net))
1338 return -EINVAL;
1339
1340 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1341 return -ENODEV;
1342
1343 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL);
1344 if (err < 0)
1345 return err;
1346
1347 /*
1348 parent == TC_H_UNSPEC - unspecified parent.
1349 parent == TC_H_ROOT - class is root, which has no parent.
1350 parent == X:0 - parent is root class.
1351 parent == X:Y - parent is a node in hierarchy.
1352 parent == 0:Y - parent is X:Y, where X:0 is qdisc.
1353
1354 handle == 0:0 - generate handle from kernel pool.
1355 handle == 0:Y - class is X:Y, where X:0 is qdisc.
1356 handle == X:Y - clear.
1357 handle == X:0 - root class.
1358 */
1359
1360 /* Step 1. Determine qdisc handle X:0 */
1361
1362 if (pid != TC_H_ROOT) {
1363 u32 qid1 = TC_H_MAJ(pid);
1364
1365 if (qid && qid1) {
1366 /* If both majors are known, they must be identical. */
1367 if (qid != qid1)
1368 return -EINVAL;
1369 } else if (qid1) {
1370 qid = qid1;
1371 } else if (qid == 0)
1372 qid = dev->qdisc->handle;
1373
1374 /* Now qid is genuine qdisc handle consistent
1375 both with parent and child.
1376
1377 TC_H_MAJ(pid) still may be unspecified, complete it now.
1378 */
1379 if (pid)
1380 pid = TC_H_MAKE(qid, pid);
1381 } else {
1382 if (qid == 0)
1383 qid = dev->qdisc->handle;
1384 }
1385
1386 /* OK. Locate qdisc */
1387 if ((q = qdisc_lookup(dev, qid)) == NULL)
1388 return -ENOENT;
1389
1390 /* An check that it supports classes */
1391 cops = q->ops->cl_ops;
1392 if (cops == NULL)
1393 return -EINVAL;
1394
1395 /* Now try to get class */
1396 if (clid == 0) {
1397 if (pid == TC_H_ROOT)
1398 clid = qid;
1399 } else
1400 clid = TC_H_MAKE(qid, clid);
1401
1402 if (clid)
1403 cl = cops->get(q, clid);
1404
1405 if (cl == 0) {
1406 err = -ENOENT;
1407 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE))
1408 goto out;
1409 } else {
1410 switch (n->nlmsg_type) {
1411 case RTM_NEWTCLASS:
1412 err = -EEXIST;
1413 if (n->nlmsg_flags&NLM_F_EXCL)
1414 goto out;
1415 break;
1416 case RTM_DELTCLASS:
1417 err = -EOPNOTSUPP;
1418 if (cops->delete)
1419 err = cops->delete(q, cl);
1420 if (err == 0)
1421 tclass_notify(skb, n, q, cl, RTM_DELTCLASS);
1422 goto out;
1423 case RTM_GETTCLASS:
1424 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS);
1425 goto out;
1426 default:
1427 err = -EINVAL;
1428 goto out;
1429 }
1430 }
1431
1432 new_cl = cl;
1433 err = -EOPNOTSUPP;
1434 if (cops->change)
1435 err = cops->change(q, clid, pid, tca, &new_cl);
1436 if (err == 0)
1437 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS);
1438
1439 out:
1440 if (cl)
1441 cops->put(q, cl);
1442
1443 return err;
1444 }
1445
1446
1447 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
1448 unsigned long cl,
1449 u32 pid, u32 seq, u16 flags, int event)
1450 {
1451 struct tcmsg *tcm;
1452 struct nlmsghdr *nlh;
1453 unsigned char *b = skb_tail_pointer(skb);
1454 struct gnet_dump d;
1455 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
1456
1457 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
1458 tcm = NLMSG_DATA(nlh);
1459 tcm->tcm_family = AF_UNSPEC;
1460 tcm->tcm__pad1 = 0;
1461 tcm->tcm__pad2 = 0;
1462 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1463 tcm->tcm_parent = q->handle;
1464 tcm->tcm_handle = q->handle;
1465 tcm->tcm_info = 0;
1466 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id);
1467 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0)
1468 goto nla_put_failure;
1469
1470 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS,
1471 qdisc_root_sleeping_lock(q), &d) < 0)
1472 goto nla_put_failure;
1473
1474 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0)
1475 goto nla_put_failure;
1476
1477 if (gnet_stats_finish_copy(&d) < 0)
1478 goto nla_put_failure;
1479
1480 nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1481 return skb->len;
1482
1483 nlmsg_failure:
1484 nla_put_failure:
1485 nlmsg_trim(skb, b);
1486 return -1;
1487 }
1488
1489 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n,
1490 struct Qdisc *q, unsigned long cl, int event)
1491 {
1492 struct sk_buff *skb;
1493 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0;
1494
1495 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1496 if (!skb)
1497 return -ENOBUFS;
1498
1499 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) {
1500 kfree_skb(skb);
1501 return -EINVAL;
1502 }
1503
1504 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
1505 }
1506
1507 struct qdisc_dump_args
1508 {
1509 struct qdisc_walker w;
1510 struct sk_buff *skb;
1511 struct netlink_callback *cb;
1512 };
1513
1514 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg)
1515 {
1516 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg;
1517
1518 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid,
1519 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS);
1520 }
1521
1522 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb,
1523 struct tcmsg *tcm, struct netlink_callback *cb,
1524 int *t_p, int s_t)
1525 {
1526 struct qdisc_dump_args arg;
1527
1528 if (tc_qdisc_dump_ignore(q) ||
1529 *t_p < s_t || !q->ops->cl_ops ||
1530 (tcm->tcm_parent &&
1531 TC_H_MAJ(tcm->tcm_parent) != q->handle)) {
1532 (*t_p)++;
1533 return 0;
1534 }
1535 if (*t_p > s_t)
1536 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0]));
1537 arg.w.fn = qdisc_class_dump;
1538 arg.skb = skb;
1539 arg.cb = cb;
1540 arg.w.stop = 0;
1541 arg.w.skip = cb->args[1];
1542 arg.w.count = 0;
1543 q->ops->cl_ops->walk(q, &arg.w);
1544 cb->args[1] = arg.w.count;
1545 if (arg.w.stop)
1546 return -1;
1547 (*t_p)++;
1548 return 0;
1549 }
1550
1551 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb,
1552 struct tcmsg *tcm, struct netlink_callback *cb,
1553 int *t_p, int s_t)
1554 {
1555 struct Qdisc *q;
1556
1557 if (!root)
1558 return 0;
1559
1560 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0)
1561 return -1;
1562
1563 list_for_each_entry(q, &root->list, list) {
1564 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0)
1565 return -1;
1566 }
1567
1568 return 0;
1569 }
1570
1571 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb)
1572 {
1573 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh);
1574 struct net *net = sock_net(skb->sk);
1575 struct netdev_queue *dev_queue;
1576 struct net_device *dev;
1577 int t, s_t;
1578
1579 if (!net_eq(net, &init_net))
1580 return 0;
1581
1582 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm)))
1583 return 0;
1584 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL)
1585 return 0;
1586
1587 s_t = cb->args[0];
1588 t = 0;
1589
1590 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0)
1591 goto done;
1592
1593 dev_queue = &dev->rx_queue;
1594 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0)
1595 goto done;
1596
1597 done:
1598 cb->args[0] = t;
1599
1600 dev_put(dev);
1601 return skb->len;
1602 }
1603
1604 /* Main classifier routine: scans classifier chain attached
1605 to this qdisc, (optionally) tests for protocol and asks
1606 specific classifiers.
1607 */
1608 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp,
1609 struct tcf_result *res)
1610 {
1611 __be16 protocol = skb->protocol;
1612 int err = 0;
1613
1614 for (; tp; tp = tp->next) {
1615 if ((tp->protocol == protocol ||
1616 tp->protocol == htons(ETH_P_ALL)) &&
1617 (err = tp->classify(skb, tp, res)) >= 0) {
1618 #ifdef CONFIG_NET_CLS_ACT
1619 if (err != TC_ACT_RECLASSIFY && skb->tc_verd)
1620 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0);
1621 #endif
1622 return err;
1623 }
1624 }
1625 return -1;
1626 }
1627 EXPORT_SYMBOL(tc_classify_compat);
1628
1629 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp,
1630 struct tcf_result *res)
1631 {
1632 int err = 0;
1633 __be16 protocol;
1634 #ifdef CONFIG_NET_CLS_ACT
1635 struct tcf_proto *otp = tp;
1636 reclassify:
1637 #endif
1638 protocol = skb->protocol;
1639
1640 err = tc_classify_compat(skb, tp, res);
1641 #ifdef CONFIG_NET_CLS_ACT
1642 if (err == TC_ACT_RECLASSIFY) {
1643 u32 verd = G_TC_VERD(skb->tc_verd);
1644 tp = otp;
1645
1646 if (verd++ >= MAX_REC_LOOP) {
1647 printk("rule prio %u protocol %02x reclassify loop, "
1648 "packet dropped\n",
1649 tp->prio&0xffff, ntohs(tp->protocol));
1650 return TC_ACT_SHOT;
1651 }
1652 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd);
1653 goto reclassify;
1654 }
1655 #endif
1656 return err;
1657 }
1658 EXPORT_SYMBOL(tc_classify);
1659
1660 void tcf_destroy(struct tcf_proto *tp)
1661 {
1662 tp->ops->destroy(tp);
1663 module_put(tp->ops->owner);
1664 kfree(tp);
1665 }
1666
1667 void tcf_destroy_chain(struct tcf_proto **fl)
1668 {
1669 struct tcf_proto *tp;
1670
1671 while ((tp = *fl) != NULL) {
1672 *fl = tp->next;
1673 tcf_destroy(tp);
1674 }
1675 }
1676 EXPORT_SYMBOL(tcf_destroy_chain);
1677
1678 #ifdef CONFIG_PROC_FS
1679 static int psched_show(struct seq_file *seq, void *v)
1680 {
1681 struct timespec ts;
1682
1683 hrtimer_get_res(CLOCK_MONOTONIC, &ts);
1684 seq_printf(seq, "%08x %08x %08x %08x\n",
1685 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1),
1686 1000000,
1687 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts)));
1688
1689 return 0;
1690 }
1691
1692 static int psched_open(struct inode *inode, struct file *file)
1693 {
1694 return single_open(file, psched_show, PDE(inode)->data);
1695 }
1696
1697 static const struct file_operations psched_fops = {
1698 .owner = THIS_MODULE,
1699 .open = psched_open,
1700 .read = seq_read,
1701 .llseek = seq_lseek,
1702 .release = single_release,
1703 };
1704 #endif
1705
1706 static int __init pktsched_init(void)
1707 {
1708 register_qdisc(&pfifo_qdisc_ops);
1709 register_qdisc(&bfifo_qdisc_ops);
1710 register_qdisc(&pfifo_head_drop_qdisc_ops);
1711 register_qdisc(&mq_qdisc_ops);
1712 proc_net_fops_create(&init_net, "psched", 0, &psched_fops);
1713
1714 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL);
1715 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL);
1716 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc);
1717 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL);
1718 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL);
1719 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass);
1720
1721 return 0;
1722 }
1723
1724 subsys_initcall(pktsched_init);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree