1/* 2 * net/sched/sch_api.c Packet scheduler API. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 * Fixes: 12 * 13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired. 14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support 15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support 16 */ 17 18#include <linux/module.h> 19#include <linux/types.h> 20#include <linux/kernel.h> 21#include <linux/string.h> 22#include <linux/errno.h> 23#include <linux/skbuff.h> 24#include <linux/init.h> 25#include <linux/proc_fs.h> 26#include <linux/seq_file.h> 27#include <linux/kmod.h> 28#include <linux/list.h> 29#include <linux/hrtimer.h> 30#include <linux/lockdep.h> 31#include <linux/slab.h> 32 33#include <net/net_namespace.h> 34#include <net/sock.h> 35#include <net/netlink.h> 36#include <net/pkt_sched.h> 37 38static int qdisc_notify(struct net *net, struct sk_buff *oskb, 39 struct nlmsghdr *n, u32 clid, 40 struct Qdisc *old, struct Qdisc *new); 41static int tclass_notify(struct net *net, struct sk_buff *oskb, 42 struct nlmsghdr *n, struct Qdisc *q, 43 unsigned long cl, int event); 44 45/* 46 47 Short review. 48 ------------- 49 50 This file consists of two interrelated parts: 51 52 1. queueing disciplines manager frontend. 53 2. traffic classes manager frontend. 54 55 Generally, queueing discipline ("qdisc") is a black box, 56 which is able to enqueue packets and to dequeue them (when 57 device is ready to send something) in order and at times 58 determined by algorithm hidden in it. 59 60 qdisc's are divided to two categories: 61 - "queues", which have no internal structure visible from outside. 62 - "schedulers", which split all the packets to "traffic classes", 63 using "packet classifiers" (look at cls_api.c) 64 65 In turn, classes may have child qdiscs (as rule, queues) 66 attached to them etc. etc. etc. 67 68 The goal of the routines in this file is to translate 69 information supplied by user in the form of handles 70 to more intelligible for kernel form, to make some sanity 71 checks and part of work, which is common to all qdiscs 72 and to provide rtnetlink notifications. 73 74 All real intelligent work is done inside qdisc modules. 75 76 77 78 Every discipline has two major routines: enqueue and dequeue. 79 80 ---dequeue 81 82 dequeue usually returns a skb to send. It is allowed to return NULL, 83 but it does not mean that queue is empty, it just means that 84 discipline does not want to send anything this time. 85 Queue is really empty if q->q.qlen == 0. 86 For complicated disciplines with multiple queues q->q is not 87 real packet queue, but however q->q.qlen must be valid. 88 89 ---enqueue 90 91 enqueue returns 0, if packet was enqueued successfully. 92 If packet (this one or another one) was dropped, it returns 93 not zero error code. 94 NET_XMIT_DROP - this packet dropped 95 Expected action: do not backoff, but wait until queue will clear. 96 NET_XMIT_CN - probably this packet enqueued, but another one dropped. 97 Expected action: backoff or ignore 98 NET_XMIT_POLICED - dropped by police. 99 Expected action: backoff or error to real-time apps. 100 101 Auxiliary routines: 102 103 ---peek 104 105 like dequeue but without removing a packet from the queue 106 107 ---reset 108 109 returns qdisc to initial state: purge all buffers, clear all 110 timers, counters (except for statistics) etc. 111 112 ---init 113 114 initializes newly created qdisc. 115 116 ---destroy 117 118 destroys resources allocated by init and during lifetime of qdisc. 119 120 ---change 121 122 changes qdisc parameters. 123 */ 124 125/* Protects list of registered TC modules. It is pure SMP lock. */ 126static DEFINE_RWLOCK(qdisc_mod_lock); 127 128 129/************************************************ 130 * Queueing disciplines manipulation. * 131 ************************************************/ 132 133 134/* The list of all installed queueing disciplines. */ 135 136static struct Qdisc_ops *qdisc_base; 137 138/* Register/uregister queueing discipline */ 139 140int register_qdisc(struct Qdisc_ops *qops) 141{ 142 struct Qdisc_ops *q, **qp; 143 int rc = -EEXIST; 144 145 write_lock(&qdisc_mod_lock); 146 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 147 if (!strcmp(qops->id, q->id)) 148 goto out; 149 150 if (qops->enqueue == NULL) 151 qops->enqueue = noop_qdisc_ops.enqueue; 152 if (qops->peek == NULL) { 153 if (qops->dequeue == NULL) 154 qops->peek = noop_qdisc_ops.peek; 155 else 156 goto out_einval; 157 } 158 if (qops->dequeue == NULL) 159 qops->dequeue = noop_qdisc_ops.dequeue; 160 161 if (qops->cl_ops) { 162 const struct Qdisc_class_ops *cops = qops->cl_ops; 163 164 if (!(cops->get && cops->put && cops->walk && cops->leaf)) 165 goto out_einval; 166 167 if (cops->tcf_chain && !(cops->bind_tcf && cops->unbind_tcf)) 168 goto out_einval; 169 } 170 171 qops->next = NULL; 172 *qp = qops; 173 rc = 0; 174out: 175 write_unlock(&qdisc_mod_lock); 176 return rc; 177 178out_einval: 179 rc = -EINVAL; 180 goto out; 181} 182EXPORT_SYMBOL(register_qdisc); 183 184int unregister_qdisc(struct Qdisc_ops *qops) 185{ 186 struct Qdisc_ops *q, **qp; 187 int err = -ENOENT; 188 189 write_lock(&qdisc_mod_lock); 190 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 191 if (q == qops) 192 break; 193 if (q) { 194 *qp = q->next; 195 q->next = NULL; 196 err = 0; 197 } 198 write_unlock(&qdisc_mod_lock); 199 return err; 200} 201EXPORT_SYMBOL(unregister_qdisc); 202 203/* We know handle. Find qdisc among all qdisc's attached to device 204 (root qdisc, all its children, children of children etc.) 205 */ 206 207static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 208{ 209 struct Qdisc *q; 210 211 if (!(root->flags & TCQ_F_BUILTIN) && 212 root->handle == handle) 213 return root; 214 215 list_for_each_entry(q, &root->list, list) { 216 if (q->handle == handle) 217 return q; 218 } 219 return NULL; 220} 221 222static void qdisc_list_add(struct Qdisc *q) 223{ 224 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 225 list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list); 226} 227 228void qdisc_list_del(struct Qdisc *q) 229{ 230 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 231 list_del(&q->list); 232} 233EXPORT_SYMBOL(qdisc_list_del); 234 235struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 236{ 237 struct Qdisc *q; 238 239 q = qdisc_match_from_root(dev->qdisc, handle); 240 if (q) 241 goto out; 242 243 if (dev_ingress_queue(dev)) 244 q = qdisc_match_from_root( 245 dev_ingress_queue(dev)->qdisc_sleeping, 246 handle); 247out: 248 return q; 249} 250 251static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 252{ 253 unsigned long cl; 254 struct Qdisc *leaf; 255 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 256 257 if (cops == NULL) 258 return NULL; 259 cl = cops->get(p, classid); 260 261 if (cl == 0) 262 return NULL; 263 leaf = cops->leaf(p, cl); 264 cops->put(p, cl); 265 return leaf; 266} 267 268/* Find queueing discipline by name */ 269 270static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 271{ 272 struct Qdisc_ops *q = NULL; 273 274 if (kind) { 275 read_lock(&qdisc_mod_lock); 276 for (q = qdisc_base; q; q = q->next) { 277 if (nla_strcmp(kind, q->id) == 0) { 278 if (!try_module_get(q->owner)) 279 q = NULL; 280 break; 281 } 282 } 283 read_unlock(&qdisc_mod_lock); 284 } 285 return q; 286} 287 288static struct qdisc_rate_table *qdisc_rtab_list; 289 290struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab) 291{ 292 struct qdisc_rate_table *rtab; 293 294 if (tab == NULL || r->rate == 0 || r->cell_log == 0 || 295 nla_len(tab) != TC_RTAB_SIZE) 296 return NULL; 297 298 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 299 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) && 300 !memcmp(&rtab->data, nla_data(tab), 1024)) { 301 rtab->refcnt++; 302 return rtab; 303 } 304 } 305 306 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 307 if (rtab) { 308 rtab->rate = *r; 309 rtab->refcnt = 1; 310 memcpy(rtab->data, nla_data(tab), 1024); 311 rtab->next = qdisc_rtab_list; 312 qdisc_rtab_list = rtab; 313 } 314 return rtab; 315} 316EXPORT_SYMBOL(qdisc_get_rtab); 317 318void qdisc_put_rtab(struct qdisc_rate_table *tab) 319{ 320 struct qdisc_rate_table *rtab, **rtabp; 321 322 if (!tab || --tab->refcnt) 323 return; 324 325 for (rtabp = &qdisc_rtab_list; 326 (rtab = *rtabp) != NULL; 327 rtabp = &rtab->next) { 328 if (rtab == tab) { 329 *rtabp = rtab->next; 330 kfree(rtab); 331 return; 332 } 333 } 334} 335EXPORT_SYMBOL(qdisc_put_rtab); 336 337static LIST_HEAD(qdisc_stab_list); 338static DEFINE_SPINLOCK(qdisc_stab_lock); 339 340static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 341 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 342 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 343}; 344 345static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt) 346{ 347 struct nlattr *tb[TCA_STAB_MAX + 1]; 348 struct qdisc_size_table *stab; 349 struct tc_sizespec *s; 350 unsigned int tsize = 0; 351 u16 *tab = NULL; 352 int err; 353 354 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy); 355 if (err < 0) 356 return ERR_PTR(err); 357 if (!tb[TCA_STAB_BASE]) 358 return ERR_PTR(-EINVAL); 359 360 s = nla_data(tb[TCA_STAB_BASE]); 361 362 if (s->tsize > 0) { 363 if (!tb[TCA_STAB_DATA]) 364 return ERR_PTR(-EINVAL); 365 tab = nla_data(tb[TCA_STAB_DATA]); 366 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 367 } 368 369 if (tsize != s->tsize || (!tab && tsize > 0)) 370 return ERR_PTR(-EINVAL); 371 372 spin_lock(&qdisc_stab_lock); 373 374 list_for_each_entry(stab, &qdisc_stab_list, list) { 375 if (memcmp(&stab->szopts, s, sizeof(*s))) 376 continue; 377 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16))) 378 continue; 379 stab->refcnt++; 380 spin_unlock(&qdisc_stab_lock); 381 return stab; 382 } 383 384 spin_unlock(&qdisc_stab_lock); 385 386 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); 387 if (!stab) 388 return ERR_PTR(-ENOMEM); 389 390 stab->refcnt = 1; 391 stab->szopts = *s; 392 if (tsize > 0) 393 memcpy(stab->data, tab, tsize * sizeof(u16)); 394 395 spin_lock(&qdisc_stab_lock); 396 list_add_tail(&stab->list, &qdisc_stab_list); 397 spin_unlock(&qdisc_stab_lock); 398 399 return stab; 400} 401 402static void stab_kfree_rcu(struct rcu_head *head) 403{ 404 kfree(container_of(head, struct qdisc_size_table, rcu)); 405} 406 407void qdisc_put_stab(struct qdisc_size_table *tab) 408{ 409 if (!tab) 410 return; 411 412 spin_lock(&qdisc_stab_lock); 413 414 if (--tab->refcnt == 0) { 415 list_del(&tab->list); 416 call_rcu_bh(&tab->rcu, stab_kfree_rcu); 417 } 418 419 spin_unlock(&qdisc_stab_lock); 420} 421EXPORT_SYMBOL(qdisc_put_stab); 422 423static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 424{ 425 struct nlattr *nest; 426 427 nest = nla_nest_start(skb, TCA_STAB); 428 if (nest == NULL) 429 goto nla_put_failure; 430 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts)) 431 goto nla_put_failure; 432 nla_nest_end(skb, nest); 433 434 return skb->len; 435 436nla_put_failure: 437 return -1; 438} 439 440void __qdisc_calculate_pkt_len(struct sk_buff *skb, const struct qdisc_size_table *stab) 441{ 442 int pkt_len, slot; 443 444 pkt_len = skb->len + stab->szopts.overhead; 445 if (unlikely(!stab->szopts.tsize)) 446 goto out; 447 448 slot = pkt_len + stab->szopts.cell_align; 449 if (unlikely(slot < 0)) 450 slot = 0; 451 452 slot >>= stab->szopts.cell_log; 453 if (likely(slot < stab->szopts.tsize)) 454 pkt_len = stab->data[slot]; 455 else 456 pkt_len = stab->data[stab->szopts.tsize - 1] * 457 (slot / stab->szopts.tsize) + 458 stab->data[slot % stab->szopts.tsize]; 459 460 pkt_len <<= stab->szopts.size_log; 461out: 462 if (unlikely(pkt_len < 1)) 463 pkt_len = 1; 464 qdisc_skb_cb(skb)->pkt_len = pkt_len; 465} 466EXPORT_SYMBOL(__qdisc_calculate_pkt_len); 467 468void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc) 469{ 470 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { 471 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n", 472 txt, qdisc->ops->id, qdisc->handle >> 16); 473 qdisc->flags |= TCQ_F_WARN_NONWC; 474 } 475} 476EXPORT_SYMBOL(qdisc_warn_nonwc); 477 478static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 479{ 480 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 481 timer); 482 483 qdisc_unthrottled(wd->qdisc); 484 __netif_schedule(qdisc_root(wd->qdisc)); 485 486 return HRTIMER_NORESTART; 487} 488 489void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc) 490{ 491 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 492 wd->timer.function = qdisc_watchdog; 493 wd->qdisc = qdisc; 494} 495EXPORT_SYMBOL(qdisc_watchdog_init); 496 497void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires) 498{ 499 if (test_bit(__QDISC_STATE_DEACTIVATED, 500 &qdisc_root_sleeping(wd->qdisc)->state)) 501 return; 502 503 qdisc_throttled(wd->qdisc); 504 505 hrtimer_start(&wd->timer, 506 ns_to_ktime(expires), 507 HRTIMER_MODE_ABS); 508} 509EXPORT_SYMBOL(qdisc_watchdog_schedule_ns); 510 511void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 512{ 513 hrtimer_cancel(&wd->timer); 514 qdisc_unthrottled(wd->qdisc); 515} 516EXPORT_SYMBOL(qdisc_watchdog_cancel); 517 518static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 519{ 520 unsigned int size = n * sizeof(struct hlist_head), i; 521 struct hlist_head *h; 522 523 if (size <= PAGE_SIZE) 524 h = kmalloc(size, GFP_KERNEL); 525 else 526 h = (struct hlist_head *) 527 __get_free_pages(GFP_KERNEL, get_order(size)); 528 529 if (h != NULL) { 530 for (i = 0; i < n; i++) 531 INIT_HLIST_HEAD(&h[i]); 532 } 533 return h; 534} 535 536static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n) 537{ 538 unsigned int size = n * sizeof(struct hlist_head); 539 540 if (size <= PAGE_SIZE) 541 kfree(h); 542 else 543 free_pages((unsigned long)h, get_order(size)); 544} 545 546void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 547{ 548 struct Qdisc_class_common *cl; 549 struct hlist_node *next; 550 struct hlist_head *nhash, *ohash; 551 unsigned int nsize, nmask, osize; 552 unsigned int i, h; 553 554 /* Rehash when load factor exceeds 0.75 */ 555 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 556 return; 557 nsize = clhash->hashsize * 2; 558 nmask = nsize - 1; 559 nhash = qdisc_class_hash_alloc(nsize); 560 if (nhash == NULL) 561 return; 562 563 ohash = clhash->hash; 564 osize = clhash->hashsize; 565 566 sch_tree_lock(sch); 567 for (i = 0; i < osize; i++) { 568 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) { 569 h = qdisc_class_hash(cl->classid, nmask); 570 hlist_add_head(&cl->hnode, &nhash[h]); 571 } 572 } 573 clhash->hash = nhash; 574 clhash->hashsize = nsize; 575 clhash->hashmask = nmask; 576 sch_tree_unlock(sch); 577 578 qdisc_class_hash_free(ohash, osize); 579} 580EXPORT_SYMBOL(qdisc_class_hash_grow); 581 582int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 583{ 584 unsigned int size = 4; 585 586 clhash->hash = qdisc_class_hash_alloc(size); 587 if (clhash->hash == NULL) 588 return -ENOMEM; 589 clhash->hashsize = size; 590 clhash->hashmask = size - 1; 591 clhash->hashelems = 0; 592 return 0; 593} 594EXPORT_SYMBOL(qdisc_class_hash_init); 595 596void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 597{ 598 qdisc_class_hash_free(clhash->hash, clhash->hashsize); 599} 600EXPORT_SYMBOL(qdisc_class_hash_destroy); 601 602void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 603 struct Qdisc_class_common *cl) 604{ 605 unsigned int h; 606 607 INIT_HLIST_NODE(&cl->hnode); 608 h = qdisc_class_hash(cl->classid, clhash->hashmask); 609 hlist_add_head(&cl->hnode, &clhash->hash[h]); 610 clhash->hashelems++; 611} 612EXPORT_SYMBOL(qdisc_class_hash_insert); 613 614void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 615 struct Qdisc_class_common *cl) 616{ 617 hlist_del(&cl->hnode); 618 clhash->hashelems--; 619} 620EXPORT_SYMBOL(qdisc_class_hash_remove); 621 622/* Allocate an unique handle from space managed by kernel 623 * Possible range is [8000-FFFF]:0000 (0x8000 values) 624 */ 625static u32 qdisc_alloc_handle(struct net_device *dev) 626{ 627 int i = 0x8000; 628 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 629 630 do { 631 autohandle += TC_H_MAKE(0x10000U, 0); 632 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 633 autohandle = TC_H_MAKE(0x80000000U, 0); 634 if (!qdisc_lookup(dev, autohandle)) 635 return autohandle; 636 cond_resched(); 637 } while (--i > 0); 638 639 return 0; 640} 641 642void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n) 643{ 644 const struct Qdisc_class_ops *cops; 645 unsigned long cl; 646 u32 parentid; 647 648 if (n == 0) 649 return; 650 while ((parentid = sch->parent)) { 651 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 652 return; 653 654 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 655 if (sch == NULL) { 656 WARN_ON(parentid != TC_H_ROOT); 657 return; 658 } 659 cops = sch->ops->cl_ops; 660 if (cops->qlen_notify) { 661 cl = cops->get(sch, parentid); 662 cops->qlen_notify(sch, cl); 663 cops->put(sch, cl); 664 } 665 sch->q.qlen -= n; 666 } 667} 668EXPORT_SYMBOL(qdisc_tree_decrease_qlen); 669 670static void notify_and_destroy(struct net *net, struct sk_buff *skb, 671 struct nlmsghdr *n, u32 clid, 672 struct Qdisc *old, struct Qdisc *new) 673{ 674 if (new || old) 675 qdisc_notify(net, skb, n, clid, old, new); 676 677 if (old) 678 qdisc_destroy(old); 679} 680 681/* Graft qdisc "new" to class "classid" of qdisc "parent" or 682 * to device "dev". 683 * 684 * When appropriate send a netlink notification using 'skb' 685 * and "n". 686 * 687 * On success, destroy old qdisc. 688 */ 689 690static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 691 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 692 struct Qdisc *new, struct Qdisc *old) 693{ 694 struct Qdisc *q = old; 695 struct net *net = dev_net(dev); 696 int err = 0; 697 698 if (parent == NULL) { 699 unsigned int i, num_q, ingress; 700 701 ingress = 0; 702 num_q = dev->num_tx_queues; 703 if ((q && q->flags & TCQ_F_INGRESS) || 704 (new && new->flags & TCQ_F_INGRESS)) { 705 num_q = 1; 706 ingress = 1; 707 if (!dev_ingress_queue(dev)) 708 return -ENOENT; 709 } 710 711 if (dev->flags & IFF_UP) 712 dev_deactivate(dev); 713 714 if (new && new->ops->attach) { 715 new->ops->attach(new); 716 num_q = 0; 717 } 718 719 for (i = 0; i < num_q; i++) { 720 struct netdev_queue *dev_queue = dev_ingress_queue(dev); 721 722 if (!ingress) 723 dev_queue = netdev_get_tx_queue(dev, i); 724 725 old = dev_graft_qdisc(dev_queue, new); 726 if (new && i > 0) 727 atomic_inc(&new->refcnt); 728 729 if (!ingress) 730 qdisc_destroy(old); 731 } 732 733 if (!ingress) { 734 notify_and_destroy(net, skb, n, classid, 735 dev->qdisc, new); 736 if (new && !new->ops->attach) 737 atomic_inc(&new->refcnt); 738 dev->qdisc = new ? : &noop_qdisc; 739 } else { 740 notify_and_destroy(net, skb, n, classid, old, new); 741 } 742 743 if (dev->flags & IFF_UP) 744 dev_activate(dev); 745 } else { 746 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 747 748 err = -EOPNOTSUPP; 749 if (cops && cops->graft) { 750 unsigned long cl = cops->get(parent, classid); 751 if (cl) { 752 err = cops->graft(parent, cl, new, &old); 753 cops->put(parent, cl); 754 } else 755 err = -ENOENT; 756 } 757 if (!err) 758 notify_and_destroy(net, skb, n, classid, old, new); 759 } 760 return err; 761} 762 763/* lockdep annotation is needed for ingress; egress gets it only for name */ 764static struct lock_class_key qdisc_tx_lock; 765static struct lock_class_key qdisc_rx_lock; 766 767/* 768 Allocate and initialize new qdisc. 769 770 Parameters are passed via opt. 771 */ 772 773static struct Qdisc * 774qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue, 775 struct Qdisc *p, u32 parent, u32 handle, 776 struct nlattr **tca, int *errp) 777{ 778 int err; 779 struct nlattr *kind = tca[TCA_KIND]; 780 struct Qdisc *sch; 781 struct Qdisc_ops *ops; 782 struct qdisc_size_table *stab; 783 784 ops = qdisc_lookup_ops(kind); 785#ifdef CONFIG_MODULES 786 if (ops == NULL && kind != NULL) { 787 char name[IFNAMSIZ]; 788 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) { 789 /* We dropped the RTNL semaphore in order to 790 * perform the module load. So, even if we 791 * succeeded in loading the module we have to 792 * tell the caller to replay the request. We 793 * indicate this using -EAGAIN. 794 * We replay the request because the device may 795 * go away in the mean time. 796 */ 797 rtnl_unlock(); 798 request_module("sch_%s", name); 799 rtnl_lock(); 800 ops = qdisc_lookup_ops(kind); 801 if (ops != NULL) { 802 /* We will try again qdisc_lookup_ops, 803 * so don't keep a reference. 804 */ 805 module_put(ops->owner); 806 err = -EAGAIN; 807 goto err_out; 808 } 809 } 810 } 811#endif 812 813 err = -ENOENT; 814 if (ops == NULL) 815 goto err_out; 816 817 sch = qdisc_alloc(dev_queue, ops); 818 if (IS_ERR(sch)) { 819 err = PTR_ERR(sch); 820 goto err_out2; 821 } 822 823 sch->parent = parent; 824 825 if (handle == TC_H_INGRESS) { 826 sch->flags |= TCQ_F_INGRESS; 827 handle = TC_H_MAKE(TC_H_INGRESS, 0); 828 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock); 829 } else { 830 if (handle == 0) { 831 handle = qdisc_alloc_handle(dev); 832 err = -ENOMEM; 833 if (handle == 0) 834 goto err_out3; 835 } 836 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock); 837 if (!netif_is_multiqueue(dev)) 838 sch->flags |= TCQ_F_ONETXQUEUE; 839 } 840 841 sch->handle = handle; 842 843 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) { 844 if (tca[TCA_STAB]) { 845 stab = qdisc_get_stab(tca[TCA_STAB]); 846 if (IS_ERR(stab)) { 847 err = PTR_ERR(stab); 848 goto err_out4; 849 } 850 rcu_assign_pointer(sch->stab, stab); 851 } 852 if (tca[TCA_RATE]) { 853 spinlock_t *root_lock; 854 855 err = -EOPNOTSUPP; 856 if (sch->flags & TCQ_F_MQROOT) 857 goto err_out4; 858 859 if ((sch->parent != TC_H_ROOT) && 860 !(sch->flags & TCQ_F_INGRESS) && 861 (!p || !(p->flags & TCQ_F_MQROOT))) 862 root_lock = qdisc_root_sleeping_lock(sch); 863 else 864 root_lock = qdisc_lock(sch); 865 866 err = gen_new_estimator(&sch->bstats, &sch->rate_est, 867 root_lock, tca[TCA_RATE]); 868 if (err) 869 goto err_out4; 870 } 871 872 qdisc_list_add(sch); 873 874 return sch; 875 } 876err_out3: 877 dev_put(dev); 878 kfree((char *) sch - sch->padded); 879err_out2: 880 module_put(ops->owner); 881err_out: 882 *errp = err; 883 return NULL; 884 885err_out4: 886 /* 887 * Any broken qdiscs that would require a ops->reset() here? 888 * The qdisc was never in action so it shouldn't be necessary. 889 */ 890 qdisc_put_stab(rtnl_dereference(sch->stab)); 891 if (ops->destroy) 892 ops->destroy(sch); 893 goto err_out3; 894} 895 896static int qdisc_change(struct Qdisc *sch, struct nlattr **tca) 897{ 898 struct qdisc_size_table *ostab, *stab = NULL; 899 int err = 0; 900 901 if (tca[TCA_OPTIONS]) { 902 if (sch->ops->change == NULL) 903 return -EINVAL; 904 err = sch->ops->change(sch, tca[TCA_OPTIONS]); 905 if (err) 906 return err; 907 } 908 909 if (tca[TCA_STAB]) { 910 stab = qdisc_get_stab(tca[TCA_STAB]); 911 if (IS_ERR(stab)) 912 return PTR_ERR(stab); 913 } 914 915 ostab = rtnl_dereference(sch->stab); 916 rcu_assign_pointer(sch->stab, stab); 917 qdisc_put_stab(ostab); 918 919 if (tca[TCA_RATE]) { 920 /* NB: ignores errors from replace_estimator 921 because change can't be undone. */ 922 if (sch->flags & TCQ_F_MQROOT) 923 goto out; 924 gen_replace_estimator(&sch->bstats, &sch->rate_est, 925 qdisc_root_sleeping_lock(sch), 926 tca[TCA_RATE]); 927 } 928out: 929 return 0; 930} 931 932struct check_loop_arg { 933 struct qdisc_walker w; 934 struct Qdisc *p; 935 int depth; 936}; 937 938static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w); 939 940static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 941{ 942 struct check_loop_arg arg; 943 944 if (q->ops->cl_ops == NULL) 945 return 0; 946 947 arg.w.stop = arg.w.skip = arg.w.count = 0; 948 arg.w.fn = check_loop_fn; 949 arg.depth = depth; 950 arg.p = p; 951 q->ops->cl_ops->walk(q, &arg.w); 952 return arg.w.stop ? -ELOOP : 0; 953} 954 955static int 956check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 957{ 958 struct Qdisc *leaf; 959 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 960 struct check_loop_arg *arg = (struct check_loop_arg *)w; 961 962 leaf = cops->leaf(q, cl); 963 if (leaf) { 964 if (leaf == arg->p || arg->depth > 7) 965 return -ELOOP; 966 return check_loop(leaf, arg->p, arg->depth + 1); 967 } 968 return 0; 969} 970 971/* 972 * Delete/get qdisc. 973 */ 974 975static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n) 976{ 977 struct net *net = sock_net(skb->sk); 978 struct tcmsg *tcm = nlmsg_data(n); 979 struct nlattr *tca[TCA_MAX + 1]; 980 struct net_device *dev; 981 u32 clid; 982 struct Qdisc *q = NULL; 983 struct Qdisc *p = NULL; 984 int err; 985 986 if ((n->nlmsg_type != RTM_GETQDISC) && !capable(CAP_NET_ADMIN)) 987 return -EPERM; 988 989 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 990 if (err < 0) 991 return err; 992 993 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 994 if (!dev) 995 return -ENODEV; 996 997 clid = tcm->tcm_parent; 998 if (clid) { 999 if (clid != TC_H_ROOT) { 1000 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1001 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1002 if (!p) 1003 return -ENOENT; 1004 q = qdisc_leaf(p, clid); 1005 } else if (dev_ingress_queue(dev)) { 1006 q = dev_ingress_queue(dev)->qdisc_sleeping; 1007 } 1008 } else { 1009 q = dev->qdisc; 1010 } 1011 if (!q) 1012 return -ENOENT; 1013 1014 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) 1015 return -EINVAL; 1016 } else { 1017 q = qdisc_lookup(dev, tcm->tcm_handle); 1018 if (!q) 1019 return -ENOENT; 1020 } 1021 1022 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1023 return -EINVAL; 1024 1025 if (n->nlmsg_type == RTM_DELQDISC) { 1026 if (!clid) 1027 return -EINVAL; 1028 if (q->handle == 0) 1029 return -ENOENT; 1030 err = qdisc_graft(dev, p, skb, n, clid, NULL, q); 1031 if (err != 0) 1032 return err; 1033 } else { 1034 qdisc_notify(net, skb, n, clid, NULL, q); 1035 } 1036 return 0; 1037} 1038 1039/* 1040 * Create/change qdisc. 1041 */ 1042 1043static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n) 1044{ 1045 struct net *net = sock_net(skb->sk); 1046 struct tcmsg *tcm; 1047 struct nlattr *tca[TCA_MAX + 1]; 1048 struct net_device *dev; 1049 u32 clid; 1050 struct Qdisc *q, *p; 1051 int err; 1052 1053 if (!capable(CAP_NET_ADMIN)) 1054 return -EPERM; 1055 1056replay: 1057 /* Reinit, just in case something touches this. */ 1058 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1059 if (err < 0) 1060 return err; 1061 1062 tcm = nlmsg_data(n); 1063 clid = tcm->tcm_parent; 1064 q = p = NULL; 1065 1066 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1067 if (!dev) 1068 return -ENODEV; 1069 1070 1071 if (clid) { 1072 if (clid != TC_H_ROOT) { 1073 if (clid != TC_H_INGRESS) { 1074 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1075 if (!p) 1076 return -ENOENT; 1077 q = qdisc_leaf(p, clid); 1078 } else if (dev_ingress_queue_create(dev)) { 1079 q = dev_ingress_queue(dev)->qdisc_sleeping; 1080 } 1081 } else { 1082 q = dev->qdisc; 1083 } 1084 1085 /* It may be default qdisc, ignore it */ 1086 if (q && q->handle == 0) 1087 q = NULL; 1088 1089 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1090 if (tcm->tcm_handle) { 1091 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) 1092 return -EEXIST; 1093 if (TC_H_MIN(tcm->tcm_handle)) 1094 return -EINVAL; 1095 q = qdisc_lookup(dev, tcm->tcm_handle); 1096 if (!q) 1097 goto create_n_graft; 1098 if (n->nlmsg_flags & NLM_F_EXCL) 1099 return -EEXIST; 1100 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1101 return -EINVAL; 1102 if (q == p || 1103 (p && check_loop(q, p, 0))) 1104 return -ELOOP; 1105 atomic_inc(&q->refcnt); 1106 goto graft; 1107 } else { 1108 if (!q) 1109 goto create_n_graft; 1110 1111 /* This magic test requires explanation. 1112 * 1113 * We know, that some child q is already 1114 * attached to this parent and have choice: 1115 * either to change it or to create/graft new one. 1116 * 1117 * 1. We are allowed to create/graft only 1118 * if CREATE and REPLACE flags are set. 1119 * 1120 * 2. If EXCL is set, requestor wanted to say, 1121 * that qdisc tcm_handle is not expected 1122 * to exist, so that we choose create/graft too. 1123 * 1124 * 3. The last case is when no flags are set. 1125 * Alas, it is sort of hole in API, we 1126 * cannot decide what to do unambiguously. 1127 * For now we select create/graft, if 1128 * user gave KIND, which does not match existing. 1129 */ 1130 if ((n->nlmsg_flags & NLM_F_CREATE) && 1131 (n->nlmsg_flags & NLM_F_REPLACE) && 1132 ((n->nlmsg_flags & NLM_F_EXCL) || 1133 (tca[TCA_KIND] && 1134 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1135 goto create_n_graft; 1136 } 1137 } 1138 } else { 1139 if (!tcm->tcm_handle) 1140 return -EINVAL; 1141 q = qdisc_lookup(dev, tcm->tcm_handle); 1142 } 1143 1144 /* Change qdisc parameters */ 1145 if (q == NULL) 1146 return -ENOENT; 1147 if (n->nlmsg_flags & NLM_F_EXCL) 1148 return -EEXIST; 1149 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1150 return -EINVAL; 1151 err = qdisc_change(q, tca); 1152 if (err == 0) 1153 qdisc_notify(net, skb, n, clid, NULL, q); 1154 return err; 1155 1156create_n_graft: 1157 if (!(n->nlmsg_flags & NLM_F_CREATE)) 1158 return -ENOENT; 1159 if (clid == TC_H_INGRESS) { 1160 if (dev_ingress_queue(dev)) 1161 q = qdisc_create(dev, dev_ingress_queue(dev), p, 1162 tcm->tcm_parent, tcm->tcm_parent, 1163 tca, &err); 1164 else 1165 err = -ENOENT; 1166 } else { 1167 struct netdev_queue *dev_queue; 1168 1169 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1170 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1171 else if (p) 1172 dev_queue = p->dev_queue; 1173 else 1174 dev_queue = netdev_get_tx_queue(dev, 0); 1175 1176 q = qdisc_create(dev, dev_queue, p, 1177 tcm->tcm_parent, tcm->tcm_handle, 1178 tca, &err); 1179 } 1180 if (q == NULL) { 1181 if (err == -EAGAIN) 1182 goto replay; 1183 return err; 1184 } 1185 1186graft: 1187 err = qdisc_graft(dev, p, skb, n, clid, q, NULL); 1188 if (err) { 1189 if (q) 1190 qdisc_destroy(q); 1191 return err; 1192 } 1193 1194 return 0; 1195} 1196 1197static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 1198 u32 portid, u32 seq, u16 flags, int event) 1199{ 1200 struct tcmsg *tcm; 1201 struct nlmsghdr *nlh; 1202 unsigned char *b = skb_tail_pointer(skb); 1203 struct gnet_dump d; 1204 struct qdisc_size_table *stab; 1205 1206 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1207 if (!nlh) 1208 goto out_nlmsg_trim; 1209 tcm = nlmsg_data(nlh); 1210 tcm->tcm_family = AF_UNSPEC; 1211 tcm->tcm__pad1 = 0; 1212 tcm->tcm__pad2 = 0; 1213 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1214 tcm->tcm_parent = clid; 1215 tcm->tcm_handle = q->handle; 1216 tcm->tcm_info = atomic_read(&q->refcnt); 1217 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1218 goto nla_put_failure; 1219 if (q->ops->dump && q->ops->dump(q, skb) < 0) 1220 goto nla_put_failure; 1221 q->qstats.qlen = q->q.qlen; 1222 1223 stab = rtnl_dereference(q->stab); 1224 if (stab && qdisc_dump_stab(skb, stab) < 0) 1225 goto nla_put_failure; 1226 1227 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1228 qdisc_root_sleeping_lock(q), &d) < 0) 1229 goto nla_put_failure; 1230 1231 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 1232 goto nla_put_failure; 1233 1234 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 || 1235 gnet_stats_copy_rate_est(&d, &q->bstats, &q->rate_est) < 0 || 1236 gnet_stats_copy_queue(&d, &q->qstats) < 0) 1237 goto nla_put_failure; 1238 1239 if (gnet_stats_finish_copy(&d) < 0) 1240 goto nla_put_failure; 1241 1242 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1243 return skb->len; 1244 1245out_nlmsg_trim: 1246nla_put_failure: 1247 nlmsg_trim(skb, b); 1248 return -1; 1249} 1250 1251static bool tc_qdisc_dump_ignore(struct Qdisc *q) 1252{ 1253 return (q->flags & TCQ_F_BUILTIN) ? true : false; 1254} 1255 1256static int qdisc_notify(struct net *net, struct sk_buff *oskb, 1257 struct nlmsghdr *n, u32 clid, 1258 struct Qdisc *old, struct Qdisc *new) 1259{ 1260 struct sk_buff *skb; 1261 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1262 1263 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1264 if (!skb) 1265 return -ENOBUFS; 1266 1267 if (old && !tc_qdisc_dump_ignore(old)) { 1268 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq, 1269 0, RTM_DELQDISC) < 0) 1270 goto err_out; 1271 } 1272 if (new && !tc_qdisc_dump_ignore(new)) { 1273 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq, 1274 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1275 goto err_out; 1276 } 1277 1278 if (skb->len) 1279 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1280 n->nlmsg_flags & NLM_F_ECHO); 1281 1282err_out: 1283 kfree_skb(skb); 1284 return -EINVAL; 1285} 1286 1287static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1288 struct netlink_callback *cb, 1289 int *q_idx_p, int s_q_idx) 1290{ 1291 int ret = 0, q_idx = *q_idx_p; 1292 struct Qdisc *q; 1293 1294 if (!root) 1295 return 0; 1296 1297 q = root; 1298 if (q_idx < s_q_idx) { 1299 q_idx++; 1300 } else { 1301 if (!tc_qdisc_dump_ignore(q) && 1302 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1303 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1304 goto done; 1305 q_idx++; 1306 } 1307 list_for_each_entry(q, &root->list, list) { 1308 if (q_idx < s_q_idx) { 1309 q_idx++; 1310 continue; 1311 } 1312 if (!tc_qdisc_dump_ignore(q) && 1313 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1314 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1315 goto done; 1316 q_idx++; 1317 } 1318 1319out: 1320 *q_idx_p = q_idx; 1321 return ret; 1322done: 1323 ret = -1; 1324 goto out; 1325} 1326 1327static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1328{ 1329 struct net *net = sock_net(skb->sk); 1330 int idx, q_idx; 1331 int s_idx, s_q_idx; 1332 struct net_device *dev; 1333 1334 s_idx = cb->args[0]; 1335 s_q_idx = q_idx = cb->args[1]; 1336 1337 rcu_read_lock(); 1338 idx = 0; 1339 for_each_netdev_rcu(net, dev) { 1340 struct netdev_queue *dev_queue; 1341 1342 if (idx < s_idx) 1343 goto cont; 1344 if (idx > s_idx) 1345 s_q_idx = 0; 1346 q_idx = 0; 1347 1348 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0) 1349 goto done; 1350 1351 dev_queue = dev_ingress_queue(dev); 1352 if (dev_queue && 1353 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1354 &q_idx, s_q_idx) < 0) 1355 goto done; 1356 1357cont: 1358 idx++; 1359 } 1360 1361done: 1362 rcu_read_unlock(); 1363 1364 cb->args[0] = idx; 1365 cb->args[1] = q_idx; 1366 1367 return skb->len; 1368} 1369 1370 1371 1372/************************************************ 1373 * Traffic classes manipulation. * 1374 ************************************************/ 1375 1376 1377 1378static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n) 1379{ 1380 struct net *net = sock_net(skb->sk); 1381 struct tcmsg *tcm = nlmsg_data(n); 1382 struct nlattr *tca[TCA_MAX + 1]; 1383 struct net_device *dev; 1384 struct Qdisc *q = NULL; 1385 const struct Qdisc_class_ops *cops; 1386 unsigned long cl = 0; 1387 unsigned long new_cl; 1388 u32 portid; 1389 u32 clid; 1390 u32 qid; 1391 int err; 1392 1393 if ((n->nlmsg_type != RTM_GETTCLASS) && !capable(CAP_NET_ADMIN)) 1394 return -EPERM; 1395 1396 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1397 if (err < 0) 1398 return err; 1399 1400 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1401 if (!dev) 1402 return -ENODEV; 1403 1404 /* 1405 parent == TC_H_UNSPEC - unspecified parent. 1406 parent == TC_H_ROOT - class is root, which has no parent. 1407 parent == X:0 - parent is root class. 1408 parent == X:Y - parent is a node in hierarchy. 1409 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 1410 1411 handle == 0:0 - generate handle from kernel pool. 1412 handle == 0:Y - class is X:Y, where X:0 is qdisc. 1413 handle == X:Y - clear. 1414 handle == X:0 - root class. 1415 */ 1416 1417 /* Step 1. Determine qdisc handle X:0 */ 1418 1419 portid = tcm->tcm_parent; 1420 clid = tcm->tcm_handle; 1421 qid = TC_H_MAJ(clid); 1422 1423 if (portid != TC_H_ROOT) { 1424 u32 qid1 = TC_H_MAJ(portid); 1425 1426 if (qid && qid1) { 1427 /* If both majors are known, they must be identical. */ 1428 if (qid != qid1) 1429 return -EINVAL; 1430 } else if (qid1) { 1431 qid = qid1; 1432 } else if (qid == 0) 1433 qid = dev->qdisc->handle; 1434 1435 /* Now qid is genuine qdisc handle consistent 1436 * both with parent and child. 1437 * 1438 * TC_H_MAJ(portid) still may be unspecified, complete it now. 1439 */ 1440 if (portid) 1441 portid = TC_H_MAKE(qid, portid); 1442 } else { 1443 if (qid == 0) 1444 qid = dev->qdisc->handle; 1445 } 1446 1447 /* OK. Locate qdisc */ 1448 q = qdisc_lookup(dev, qid); 1449 if (!q) 1450 return -ENOENT; 1451 1452 /* An check that it supports classes */ 1453 cops = q->ops->cl_ops; 1454 if (cops == NULL) 1455 return -EINVAL; 1456 1457 /* Now try to get class */ 1458 if (clid == 0) { 1459 if (portid == TC_H_ROOT) 1460 clid = qid; 1461 } else 1462 clid = TC_H_MAKE(qid, clid); 1463 1464 if (clid) 1465 cl = cops->get(q, clid); 1466 1467 if (cl == 0) { 1468 err = -ENOENT; 1469 if (n->nlmsg_type != RTM_NEWTCLASS || 1470 !(n->nlmsg_flags & NLM_F_CREATE)) 1471 goto out; 1472 } else { 1473 switch (n->nlmsg_type) { 1474 case RTM_NEWTCLASS: 1475 err = -EEXIST; 1476 if (n->nlmsg_flags & NLM_F_EXCL) 1477 goto out; 1478 break; 1479 case RTM_DELTCLASS: 1480 err = -EOPNOTSUPP; 1481 if (cops->delete) 1482 err = cops->delete(q, cl); 1483 if (err == 0) 1484 tclass_notify(net, skb, n, q, cl, RTM_DELTCLASS); 1485 goto out; 1486 case RTM_GETTCLASS: 1487 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS); 1488 goto out; 1489 default: 1490 err = -EINVAL; 1491 goto out; 1492 } 1493 } 1494 1495 new_cl = cl; 1496 err = -EOPNOTSUPP; 1497 if (cops->change) 1498 err = cops->change(q, clid, portid, tca, &new_cl); 1499 if (err == 0) 1500 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS); 1501 1502out: 1503 if (cl) 1504 cops->put(q, cl); 1505 1506 return err; 1507} 1508 1509 1510static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1511 unsigned long cl, 1512 u32 portid, u32 seq, u16 flags, int event) 1513{ 1514 struct tcmsg *tcm; 1515 struct nlmsghdr *nlh; 1516 unsigned char *b = skb_tail_pointer(skb); 1517 struct gnet_dump d; 1518 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1519 1520 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1521 if (!nlh) 1522 goto out_nlmsg_trim; 1523 tcm = nlmsg_data(nlh); 1524 tcm->tcm_family = AF_UNSPEC; 1525 tcm->tcm__pad1 = 0; 1526 tcm->tcm__pad2 = 0; 1527 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1528 tcm->tcm_parent = q->handle; 1529 tcm->tcm_handle = q->handle; 1530 tcm->tcm_info = 0; 1531 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1532 goto nla_put_failure; 1533 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1534 goto nla_put_failure; 1535 1536 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1537 qdisc_root_sleeping_lock(q), &d) < 0) 1538 goto nla_put_failure; 1539 1540 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1541 goto nla_put_failure; 1542 1543 if (gnet_stats_finish_copy(&d) < 0) 1544 goto nla_put_failure; 1545 1546 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1547 return skb->len; 1548 1549out_nlmsg_trim: 1550nla_put_failure: 1551 nlmsg_trim(skb, b); 1552 return -1; 1553} 1554 1555static int tclass_notify(struct net *net, struct sk_buff *oskb, 1556 struct nlmsghdr *n, struct Qdisc *q, 1557 unsigned long cl, int event) 1558{ 1559 struct sk_buff *skb; 1560 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1561 1562 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1563 if (!skb) 1564 return -ENOBUFS; 1565 1566 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) { 1567 kfree_skb(skb); 1568 return -EINVAL; 1569 } 1570 1571 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1572 n->nlmsg_flags & NLM_F_ECHO); 1573} 1574 1575struct qdisc_dump_args { 1576 struct qdisc_walker w; 1577 struct sk_buff *skb; 1578 struct netlink_callback *cb; 1579}; 1580 1581static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg) 1582{ 1583 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 1584 1585 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 1586 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS); 1587} 1588 1589static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 1590 struct tcmsg *tcm, struct netlink_callback *cb, 1591 int *t_p, int s_t) 1592{ 1593 struct qdisc_dump_args arg; 1594 1595 if (tc_qdisc_dump_ignore(q) || 1596 *t_p < s_t || !q->ops->cl_ops || 1597 (tcm->tcm_parent && 1598 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 1599 (*t_p)++; 1600 return 0; 1601 } 1602 if (*t_p > s_t) 1603 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 1604 arg.w.fn = qdisc_class_dump; 1605 arg.skb = skb; 1606 arg.cb = cb; 1607 arg.w.stop = 0; 1608 arg.w.skip = cb->args[1]; 1609 arg.w.count = 0; 1610 q->ops->cl_ops->walk(q, &arg.w); 1611 cb->args[1] = arg.w.count; 1612 if (arg.w.stop) 1613 return -1; 1614 (*t_p)++; 1615 return 0; 1616} 1617 1618static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 1619 struct tcmsg *tcm, struct netlink_callback *cb, 1620 int *t_p, int s_t) 1621{ 1622 struct Qdisc *q; 1623 1624 if (!root) 1625 return 0; 1626 1627 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 1628 return -1; 1629 1630 list_for_each_entry(q, &root->list, list) { 1631 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 1632 return -1; 1633 } 1634 1635 return 0; 1636} 1637 1638static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 1639{ 1640 struct tcmsg *tcm = nlmsg_data(cb->nlh); 1641 struct net *net = sock_net(skb->sk); 1642 struct netdev_queue *dev_queue; 1643 struct net_device *dev; 1644 int t, s_t; 1645 1646 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 1647 return 0; 1648 dev = dev_get_by_index(net, tcm->tcm_ifindex); 1649 if (!dev) 1650 return 0; 1651 1652 s_t = cb->args[0]; 1653 t = 0; 1654 1655 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0) 1656 goto done; 1657 1658 dev_queue = dev_ingress_queue(dev); 1659 if (dev_queue && 1660 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 1661 &t, s_t) < 0) 1662 goto done; 1663 1664done: 1665 cb->args[0] = t; 1666 1667 dev_put(dev); 1668 return skb->len; 1669} 1670 1671/* Main classifier routine: scans classifier chain attached 1672 * to this qdisc, (optionally) tests for protocol and asks 1673 * specific classifiers. 1674 */ 1675int tc_classify_compat(struct sk_buff *skb, const struct tcf_proto *tp, 1676 struct tcf_result *res) 1677{ 1678 __be16 protocol = skb->protocol; 1679 int err; 1680 1681 for (; tp; tp = tp->next) { 1682 if (tp->protocol != protocol && 1683 tp->protocol != htons(ETH_P_ALL)) 1684 continue; 1685 err = tp->classify(skb, tp, res); 1686 1687 if (err >= 0) { 1688#ifdef CONFIG_NET_CLS_ACT 1689 if (err != TC_ACT_RECLASSIFY && skb->tc_verd) 1690 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0); 1691#endif 1692 return err; 1693 } 1694 } 1695 return -1; 1696} 1697EXPORT_SYMBOL(tc_classify_compat); 1698 1699int tc_classify(struct sk_buff *skb, const struct tcf_proto *tp, 1700 struct tcf_result *res) 1701{ 1702 int err = 0; 1703#ifdef CONFIG_NET_CLS_ACT 1704 const struct tcf_proto *otp = tp; 1705reclassify: 1706#endif 1707 1708 err = tc_classify_compat(skb, tp, res); 1709#ifdef CONFIG_NET_CLS_ACT 1710 if (err == TC_ACT_RECLASSIFY) { 1711 u32 verd = G_TC_VERD(skb->tc_verd); 1712 tp = otp; 1713 1714 if (verd++ >= MAX_REC_LOOP) { 1715 net_notice_ratelimited("%s: packet reclassify loop rule prio %u protocol %02x\n", 1716 tp->q->ops->id, 1717 tp->prio & 0xffff, 1718 ntohs(tp->protocol)); 1719 return TC_ACT_SHOT; 1720 } 1721 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd); 1722 goto reclassify; 1723 } 1724#endif 1725 return err; 1726} 1727EXPORT_SYMBOL(tc_classify); 1728 1729void tcf_destroy(struct tcf_proto *tp) 1730{ 1731 tp->ops->destroy(tp); 1732 module_put(tp->ops->owner); 1733 kfree(tp); 1734} 1735 1736void tcf_destroy_chain(struct tcf_proto **fl) 1737{ 1738 struct tcf_proto *tp; 1739 1740 while ((tp = *fl) != NULL) { 1741 *fl = tp->next; 1742 tcf_destroy(tp); 1743 } 1744} 1745EXPORT_SYMBOL(tcf_destroy_chain); 1746 1747#ifdef CONFIG_PROC_FS 1748static int psched_show(struct seq_file *seq, void *v) 1749{ 1750 struct timespec ts; 1751 1752 hrtimer_get_res(CLOCK_MONOTONIC, &ts); 1753 seq_printf(seq, "%08x %08x %08x %08x\n", 1754 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 1755 1000000, 1756 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts))); 1757 1758 return 0; 1759} 1760 1761static int psched_open(struct inode *inode, struct file *file) 1762{ 1763 return single_open(file, psched_show, NULL); 1764} 1765 1766static const struct file_operations psched_fops = { 1767 .owner = THIS_MODULE, 1768 .open = psched_open, 1769 .read = seq_read, 1770 .llseek = seq_lseek, 1771 .release = single_release, 1772}; 1773 1774static int __net_init psched_net_init(struct net *net) 1775{ 1776 struct proc_dir_entry *e; 1777 1778 e = proc_create("psched", 0, net->proc_net, &psched_fops); 1779 if (e == NULL) 1780 return -ENOMEM; 1781 1782 return 0; 1783} 1784 1785static void __net_exit psched_net_exit(struct net *net) 1786{ 1787 remove_proc_entry("psched", net->proc_net); 1788} 1789#else 1790static int __net_init psched_net_init(struct net *net) 1791{ 1792 return 0; 1793} 1794 1795static void __net_exit psched_net_exit(struct net *net) 1796{ 1797} 1798#endif 1799 1800static struct pernet_operations psched_net_ops = { 1801 .init = psched_net_init, 1802 .exit = psched_net_exit, 1803}; 1804 1805static int __init pktsched_init(void) 1806{ 1807 int err; 1808 1809 err = register_pernet_subsys(&psched_net_ops); 1810 if (err) { 1811 pr_err("pktsched_init: " 1812 "cannot initialize per netns operations\n"); 1813 return err; 1814 } 1815 1816 register_qdisc(&pfifo_qdisc_ops); 1817 register_qdisc(&bfifo_qdisc_ops); 1818 register_qdisc(&pfifo_head_drop_qdisc_ops); 1819 register_qdisc(&mq_qdisc_ops); 1820 1821 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL); 1822 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL); 1823 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, NULL); 1824 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, NULL); 1825 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, NULL); 1826 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, NULL); 1827 1828 return 0; 1829} 1830 1831subsys_initcall(pktsched_init); 1832