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