1 /* 2 * net/sched/sch_api.c Packet scheduler API. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 * Fixes: 12 * 13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired. 14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support 15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support 16 */ 17 18 #include <linux/module.h> 19 #include <linux/types.h> 20 #include <linux/kernel.h> 21 #include <linux/string.h> 22 #include <linux/errno.h> 23 #include <linux/skbuff.h> 24 #include <linux/init.h> 25 #include <linux/proc_fs.h> 26 #include <linux/seq_file.h> 27 #include <linux/kmod.h> 28 #include <linux/list.h> 29 #include <linux/hrtimer.h> 30 #include <linux/lockdep.h> 31 32 #include <net/net_namespace.h> 33 #include <net/sock.h> 34 #include <net/netlink.h> 35 #include <net/pkt_sched.h> 36 37 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, u32 clid, 38 struct Qdisc *old, struct Qdisc *new); 39 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 40 struct Qdisc *q, unsigned long cl, int event); 41 42 /* 43 44 Short review. 45 ------------- 46 47 This file consists of two interrelated parts: 48 49 1. queueing disciplines manager frontend. 50 2. traffic classes manager frontend. 51 52 Generally, queueing discipline ("qdisc") is a black box, 53 which is able to enqueue packets and to dequeue them (when 54 device is ready to send something) in order and at times 55 determined by algorithm hidden in it. 56 57 qdisc's are divided to two categories: 58 - "queues", which have no internal structure visible from outside. 59 - "schedulers", which split all the packets to "traffic classes", 60 using "packet classifiers" (look at cls_api.c) 61 62 In turn, classes may have child qdiscs (as rule, queues) 63 attached to them etc. etc. etc. 64 65 The goal of the routines in this file is to translate 66 information supplied by user in the form of handles 67 to more intelligible for kernel form, to make some sanity 68 checks and part of work, which is common to all qdiscs 69 and to provide rtnetlink notifications. 70 71 All real intelligent work is done inside qdisc modules. 72 73 74 75 Every discipline has two major routines: enqueue and dequeue. 76 77 ---dequeue 78 79 dequeue usually returns a skb to send. It is allowed to return NULL, 80 but it does not mean that queue is empty, it just means that 81 discipline does not want to send anything this time. 82 Queue is really empty if q->q.qlen == 0. 83 For complicated disciplines with multiple queues q->q is not 84 real packet queue, but however q->q.qlen must be valid. 85 86 ---enqueue 87 88 enqueue returns 0, if packet was enqueued successfully. 89 If packet (this one or another one) was dropped, it returns 90 not zero error code. 91 NET_XMIT_DROP - this packet dropped 92 Expected action: do not backoff, but wait until queue will clear. 93 NET_XMIT_CN - probably this packet enqueued, but another one dropped. 94 Expected action: backoff or ignore 95 NET_XMIT_POLICED - dropped by police. 96 Expected action: backoff or error to real-time apps. 97 98 Auxiliary routines: 99 100 ---peek 101 102 like dequeue but without removing a packet from the queue 103 104 ---reset 105 106 returns qdisc to initial state: purge all buffers, clear all 107 timers, counters (except for statistics) etc. 108 109 ---init 110 111 initializes newly created qdisc. 112 113 ---destroy 114 115 destroys resources allocated by init and during lifetime of qdisc. 116 117 ---change 118 119 changes qdisc parameters. 120 */ 121 122 /* Protects list of registered TC modules. It is pure SMP lock. */ 123 static DEFINE_RWLOCK(qdisc_mod_lock); 124 125 126 /************************************************ 127 * Queueing disciplines manipulation. * 128 ************************************************/ 129 130 131 /* The list of all installed queueing disciplines. */ 132 133 static struct Qdisc_ops *qdisc_base; 134 135 /* Register/uregister queueing discipline */ 136 137 int register_qdisc(struct Qdisc_ops *qops) 138 { 139 struct Qdisc_ops *q, **qp; 140 int rc = -EEXIST; 141 142 write_lock(&qdisc_mod_lock); 143 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 144 if (!strcmp(qops->id, q->id)) 145 goto out; 146 147 if (qops->enqueue == NULL) 148 qops->enqueue = noop_qdisc_ops.enqueue; 149 if (qops->peek == NULL) { 150 if (qops->dequeue == NULL) { 151 qops->peek = noop_qdisc_ops.peek; 152 } else { 153 rc = -EINVAL; 154 goto out; 155 } 156 } 157 if (qops->dequeue == NULL) 158 qops->dequeue = noop_qdisc_ops.dequeue; 159 160 qops->next = NULL; 161 *qp = qops; 162 rc = 0; 163 out: 164 write_unlock(&qdisc_mod_lock); 165 return rc; 166 } 167 EXPORT_SYMBOL(register_qdisc); 168 169 int unregister_qdisc(struct Qdisc_ops *qops) 170 { 171 struct Qdisc_ops *q, **qp; 172 int err = -ENOENT; 173 174 write_lock(&qdisc_mod_lock); 175 for (qp = &qdisc_base; (q=*qp)!=NULL; qp = &q->next) 176 if (q == qops) 177 break; 178 if (q) { 179 *qp = q->next; 180 q->next = NULL; 181 err = 0; 182 } 183 write_unlock(&qdisc_mod_lock); 184 return err; 185 } 186 EXPORT_SYMBOL(unregister_qdisc); 187 188 /* We know handle. Find qdisc among all qdisc's attached to device 189 (root qdisc, all its children, children of children etc.) 190 */ 191 192 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 193 { 194 struct Qdisc *q; 195 196 if (!(root->flags & TCQ_F_BUILTIN) && 197 root->handle == handle) 198 return root; 199 200 list_for_each_entry(q, &root->list, list) { 201 if (q->handle == handle) 202 return q; 203 } 204 return NULL; 205 } 206 207 static void qdisc_list_add(struct Qdisc *q) 208 { 209 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 210 list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list); 211 } 212 213 void qdisc_list_del(struct Qdisc *q) 214 { 215 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 216 list_del(&q->list); 217 } 218 EXPORT_SYMBOL(qdisc_list_del); 219 220 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 221 { 222 struct Qdisc *q; 223 224 q = qdisc_match_from_root(dev->qdisc, handle); 225 if (q) 226 goto out; 227 228 q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle); 229 out: 230 return q; 231 } 232 233 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 234 { 235 unsigned long cl; 236 struct Qdisc *leaf; 237 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 238 239 if (cops == NULL) 240 return NULL; 241 cl = cops->get(p, classid); 242 243 if (cl == 0) 244 return NULL; 245 leaf = cops->leaf(p, cl); 246 cops->put(p, cl); 247 return leaf; 248 } 249 250 /* Find queueing discipline by name */ 251 252 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 253 { 254 struct Qdisc_ops *q = NULL; 255 256 if (kind) { 257 read_lock(&qdisc_mod_lock); 258 for (q = qdisc_base; q; q = q->next) { 259 if (nla_strcmp(kind, q->id) == 0) { 260 if (!try_module_get(q->owner)) 261 q = NULL; 262 break; 263 } 264 } 265 read_unlock(&qdisc_mod_lock); 266 } 267 return q; 268 } 269 270 static struct qdisc_rate_table *qdisc_rtab_list; 271 272 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab) 273 { 274 struct qdisc_rate_table *rtab; 275 276 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 277 if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) { 278 rtab->refcnt++; 279 return rtab; 280 } 281 } 282 283 if (tab == NULL || r->rate == 0 || r->cell_log == 0 || 284 nla_len(tab) != TC_RTAB_SIZE) 285 return NULL; 286 287 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 288 if (rtab) { 289 rtab->rate = *r; 290 rtab->refcnt = 1; 291 memcpy(rtab->data, nla_data(tab), 1024); 292 rtab->next = qdisc_rtab_list; 293 qdisc_rtab_list = rtab; 294 } 295 return rtab; 296 } 297 EXPORT_SYMBOL(qdisc_get_rtab); 298 299 void qdisc_put_rtab(struct qdisc_rate_table *tab) 300 { 301 struct qdisc_rate_table *rtab, **rtabp; 302 303 if (!tab || --tab->refcnt) 304 return; 305 306 for (rtabp = &qdisc_rtab_list; (rtab=*rtabp) != NULL; rtabp = &rtab->next) { 307 if (rtab == tab) { 308 *rtabp = rtab->next; 309 kfree(rtab); 310 return; 311 } 312 } 313 } 314 EXPORT_SYMBOL(qdisc_put_rtab); 315 316 static LIST_HEAD(qdisc_stab_list); 317 static DEFINE_SPINLOCK(qdisc_stab_lock); 318 319 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 320 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 321 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 322 }; 323 324 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt) 325 { 326 struct nlattr *tb[TCA_STAB_MAX + 1]; 327 struct qdisc_size_table *stab; 328 struct tc_sizespec *s; 329 unsigned int tsize = 0; 330 u16 *tab = NULL; 331 int err; 332 333 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy); 334 if (err < 0) 335 return ERR_PTR(err); 336 if (!tb[TCA_STAB_BASE]) 337 return ERR_PTR(-EINVAL); 338 339 s = nla_data(tb[TCA_STAB_BASE]); 340 341 if (s->tsize > 0) { 342 if (!tb[TCA_STAB_DATA]) 343 return ERR_PTR(-EINVAL); 344 tab = nla_data(tb[TCA_STAB_DATA]); 345 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 346 } 347 348 if (!s || tsize != s->tsize || (!tab && tsize > 0)) 349 return ERR_PTR(-EINVAL); 350 351 spin_lock(&qdisc_stab_lock); 352 353 list_for_each_entry(stab, &qdisc_stab_list, list) { 354 if (memcmp(&stab->szopts, s, sizeof(*s))) 355 continue; 356 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16))) 357 continue; 358 stab->refcnt++; 359 spin_unlock(&qdisc_stab_lock); 360 return stab; 361 } 362 363 spin_unlock(&qdisc_stab_lock); 364 365 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); 366 if (!stab) 367 return ERR_PTR(-ENOMEM); 368 369 stab->refcnt = 1; 370 stab->szopts = *s; 371 if (tsize > 0) 372 memcpy(stab->data, tab, tsize * sizeof(u16)); 373 374 spin_lock(&qdisc_stab_lock); 375 list_add_tail(&stab->list, &qdisc_stab_list); 376 spin_unlock(&qdisc_stab_lock); 377 378 return stab; 379 } 380 381 void qdisc_put_stab(struct qdisc_size_table *tab) 382 { 383 if (!tab) 384 return; 385 386 spin_lock(&qdisc_stab_lock); 387 388 if (--tab->refcnt == 0) { 389 list_del(&tab->list); 390 kfree(tab); 391 } 392 393 spin_unlock(&qdisc_stab_lock); 394 } 395 EXPORT_SYMBOL(qdisc_put_stab); 396 397 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 398 { 399 struct nlattr *nest; 400 401 nest = nla_nest_start(skb, TCA_STAB); 402 if (nest == NULL) 403 goto nla_put_failure; 404 NLA_PUT(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts); 405 nla_nest_end(skb, nest); 406 407 return skb->len; 408 409 nla_put_failure: 410 return -1; 411 } 412 413 void qdisc_calculate_pkt_len(struct sk_buff *skb, struct qdisc_size_table *stab) 414 { 415 int pkt_len, slot; 416 417 pkt_len = skb->len + stab->szopts.overhead; 418 if (unlikely(!stab->szopts.tsize)) 419 goto out; 420 421 slot = pkt_len + stab->szopts.cell_align; 422 if (unlikely(slot < 0)) 423 slot = 0; 424 425 slot >>= stab->szopts.cell_log; 426 if (likely(slot < stab->szopts.tsize)) 427 pkt_len = stab->data[slot]; 428 else 429 pkt_len = stab->data[stab->szopts.tsize - 1] * 430 (slot / stab->szopts.tsize) + 431 stab->data[slot % stab->szopts.tsize]; 432 433 pkt_len <<= stab->szopts.size_log; 434 out: 435 if (unlikely(pkt_len < 1)) 436 pkt_len = 1; 437 qdisc_skb_cb(skb)->pkt_len = pkt_len; 438 } 439 EXPORT_SYMBOL(qdisc_calculate_pkt_len); 440 441 void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc) 442 { 443 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { 444 printk(KERN_WARNING 445 "%s: %s qdisc %X: is non-work-conserving?\n", 446 txt, qdisc->ops->id, qdisc->handle >> 16); 447 qdisc->flags |= TCQ_F_WARN_NONWC; 448 } 449 } 450 EXPORT_SYMBOL(qdisc_warn_nonwc); 451 452 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 453 { 454 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 455 timer); 456 457 wd->qdisc->flags &= ~TCQ_F_THROTTLED; 458 __netif_schedule(qdisc_root(wd->qdisc)); 459 460 return HRTIMER_NORESTART; 461 } 462 463 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc) 464 { 465 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 466 wd->timer.function = qdisc_watchdog; 467 wd->qdisc = qdisc; 468 } 469 EXPORT_SYMBOL(qdisc_watchdog_init); 470 471 void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires) 472 { 473 ktime_t time; 474 475 if (test_bit(__QDISC_STATE_DEACTIVATED, 476 &qdisc_root_sleeping(wd->qdisc)->state)) 477 return; 478 479 wd->qdisc->flags |= TCQ_F_THROTTLED; 480 time = ktime_set(0, 0); 481 time = ktime_add_ns(time, PSCHED_TICKS2NS(expires)); 482 hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS); 483 } 484 EXPORT_SYMBOL(qdisc_watchdog_schedule); 485 486 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 487 { 488 hrtimer_cancel(&wd->timer); 489 wd->qdisc->flags &= ~TCQ_F_THROTTLED; 490 } 491 EXPORT_SYMBOL(qdisc_watchdog_cancel); 492 493 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 494 { 495 unsigned int size = n * sizeof(struct hlist_head), i; 496 struct hlist_head *h; 497 498 if (size <= PAGE_SIZE) 499 h = kmalloc(size, GFP_KERNEL); 500 else 501 h = (struct hlist_head *) 502 __get_free_pages(GFP_KERNEL, get_order(size)); 503 504 if (h != NULL) { 505 for (i = 0; i < n; i++) 506 INIT_HLIST_HEAD(&h[i]); 507 } 508 return h; 509 } 510 511 static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n) 512 { 513 unsigned int size = n * sizeof(struct hlist_head); 514 515 if (size <= PAGE_SIZE) 516 kfree(h); 517 else 518 free_pages((unsigned long)h, get_order(size)); 519 } 520 521 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 522 { 523 struct Qdisc_class_common *cl; 524 struct hlist_node *n, *next; 525 struct hlist_head *nhash, *ohash; 526 unsigned int nsize, nmask, osize; 527 unsigned int i, h; 528 529 /* Rehash when load factor exceeds 0.75 */ 530 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 531 return; 532 nsize = clhash->hashsize * 2; 533 nmask = nsize - 1; 534 nhash = qdisc_class_hash_alloc(nsize); 535 if (nhash == NULL) 536 return; 537 538 ohash = clhash->hash; 539 osize = clhash->hashsize; 540 541 sch_tree_lock(sch); 542 for (i = 0; i < osize; i++) { 543 hlist_for_each_entry_safe(cl, n, next, &ohash[i], hnode) { 544 h = qdisc_class_hash(cl->classid, nmask); 545 hlist_add_head(&cl->hnode, &nhash[h]); 546 } 547 } 548 clhash->hash = nhash; 549 clhash->hashsize = nsize; 550 clhash->hashmask = nmask; 551 sch_tree_unlock(sch); 552 553 qdisc_class_hash_free(ohash, osize); 554 } 555 EXPORT_SYMBOL(qdisc_class_hash_grow); 556 557 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 558 { 559 unsigned int size = 4; 560 561 clhash->hash = qdisc_class_hash_alloc(size); 562 if (clhash->hash == NULL) 563 return -ENOMEM; 564 clhash->hashsize = size; 565 clhash->hashmask = size - 1; 566 clhash->hashelems = 0; 567 return 0; 568 } 569 EXPORT_SYMBOL(qdisc_class_hash_init); 570 571 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 572 { 573 qdisc_class_hash_free(clhash->hash, clhash->hashsize); 574 } 575 EXPORT_SYMBOL(qdisc_class_hash_destroy); 576 577 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 578 struct Qdisc_class_common *cl) 579 { 580 unsigned int h; 581 582 INIT_HLIST_NODE(&cl->hnode); 583 h = qdisc_class_hash(cl->classid, clhash->hashmask); 584 hlist_add_head(&cl->hnode, &clhash->hash[h]); 585 clhash->hashelems++; 586 } 587 EXPORT_SYMBOL(qdisc_class_hash_insert); 588 589 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 590 struct Qdisc_class_common *cl) 591 { 592 hlist_del(&cl->hnode); 593 clhash->hashelems--; 594 } 595 EXPORT_SYMBOL(qdisc_class_hash_remove); 596 597 /* Allocate an unique handle from space managed by kernel */ 598 599 static u32 qdisc_alloc_handle(struct net_device *dev) 600 { 601 int i = 0x10000; 602 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 603 604 do { 605 autohandle += TC_H_MAKE(0x10000U, 0); 606 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 607 autohandle = TC_H_MAKE(0x80000000U, 0); 608 } while (qdisc_lookup(dev, autohandle) && --i > 0); 609 610 return i>0 ? autohandle : 0; 611 } 612 613 void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n) 614 { 615 const struct Qdisc_class_ops *cops; 616 unsigned long cl; 617 u32 parentid; 618 619 if (n == 0) 620 return; 621 while ((parentid = sch->parent)) { 622 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 623 return; 624 625 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 626 if (sch == NULL) { 627 WARN_ON(parentid != TC_H_ROOT); 628 return; 629 } 630 cops = sch->ops->cl_ops; 631 if (cops->qlen_notify) { 632 cl = cops->get(sch, parentid); 633 cops->qlen_notify(sch, cl); 634 cops->put(sch, cl); 635 } 636 sch->q.qlen -= n; 637 } 638 } 639 EXPORT_SYMBOL(qdisc_tree_decrease_qlen); 640 641 static void notify_and_destroy(struct sk_buff *skb, struct nlmsghdr *n, u32 clid, 642 struct Qdisc *old, struct Qdisc *new) 643 { 644 if (new || old) 645 qdisc_notify(skb, n, clid, old, new); 646 647 if (old) 648 qdisc_destroy(old); 649 } 650 651 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 652 * to device "dev". 653 * 654 * When appropriate send a netlink notification using 'skb' 655 * and "n". 656 * 657 * On success, destroy old qdisc. 658 */ 659 660 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 661 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 662 struct Qdisc *new, struct Qdisc *old) 663 { 664 struct Qdisc *q = old; 665 int err = 0; 666 667 if (parent == NULL) { 668 unsigned int i, num_q, ingress; 669 670 ingress = 0; 671 num_q = dev->num_tx_queues; 672 if ((q && q->flags & TCQ_F_INGRESS) || 673 (new && new->flags & TCQ_F_INGRESS)) { 674 num_q = 1; 675 ingress = 1; 676 } 677 678 if (dev->flags & IFF_UP) 679 dev_deactivate(dev); 680 681 if (new && new->ops->attach) { 682 new->ops->attach(new); 683 num_q = 0; 684 } 685 686 for (i = 0; i < num_q; i++) { 687 struct netdev_queue *dev_queue = &dev->rx_queue; 688 689 if (!ingress) 690 dev_queue = netdev_get_tx_queue(dev, i); 691 692 old = dev_graft_qdisc(dev_queue, new); 693 if (new && i > 0) 694 atomic_inc(&new->refcnt); 695 696 if (!ingress) 697 qdisc_destroy(old); 698 } 699 700 if (!ingress) { 701 notify_and_destroy(skb, n, classid, dev->qdisc, new); 702 if (new && !new->ops->attach) 703 atomic_inc(&new->refcnt); 704 dev->qdisc = new ? : &noop_qdisc; 705 } else { 706 notify_and_destroy(skb, n, classid, old, new); 707 } 708 709 if (dev->flags & IFF_UP) 710 dev_activate(dev); 711 } else { 712 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 713 714 err = -EOPNOTSUPP; 715 if (cops && cops->graft) { 716 unsigned long cl = cops->get(parent, classid); 717 if (cl) { 718 err = cops->graft(parent, cl, new, &old); 719 cops->put(parent, cl); 720 } else 721 err = -ENOENT; 722 } 723 if (!err) 724 notify_and_destroy(skb, n, classid, old, new); 725 } 726 return err; 727 } 728 729 /* lockdep annotation is needed for ingress; egress gets it only for name */ 730 static struct lock_class_key qdisc_tx_lock; 731 static struct lock_class_key qdisc_rx_lock; 732 733 /* 734 Allocate and initialize new qdisc. 735 736 Parameters are passed via opt. 737 */ 738 739 static struct Qdisc * 740 qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue, 741 struct Qdisc *p, u32 parent, u32 handle, 742 struct nlattr **tca, int *errp) 743 { 744 int err; 745 struct nlattr *kind = tca[TCA_KIND]; 746 struct Qdisc *sch; 747 struct Qdisc_ops *ops; 748 struct qdisc_size_table *stab; 749 750 ops = qdisc_lookup_ops(kind); 751 #ifdef CONFIG_MODULES 752 if (ops == NULL && kind != NULL) { 753 char name[IFNAMSIZ]; 754 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) { 755 /* We dropped the RTNL semaphore in order to 756 * perform the module load. So, even if we 757 * succeeded in loading the module we have to 758 * tell the caller to replay the request. We 759 * indicate this using -EAGAIN. 760 * We replay the request because the device may 761 * go away in the mean time. 762 */ 763 rtnl_unlock(); 764 request_module("sch_%s", name); 765 rtnl_lock(); 766 ops = qdisc_lookup_ops(kind); 767 if (ops != NULL) { 768 /* We will try again qdisc_lookup_ops, 769 * so don't keep a reference. 770 */ 771 module_put(ops->owner); 772 err = -EAGAIN; 773 goto err_out; 774 } 775 } 776 } 777 #endif 778 779 err = -ENOENT; 780 if (ops == NULL) 781 goto err_out; 782 783 sch = qdisc_alloc(dev_queue, ops); 784 if (IS_ERR(sch)) { 785 err = PTR_ERR(sch); 786 goto err_out2; 787 } 788 789 sch->parent = parent; 790 791 if (handle == TC_H_INGRESS) { 792 sch->flags |= TCQ_F_INGRESS; 793 handle = TC_H_MAKE(TC_H_INGRESS, 0); 794 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock); 795 } else { 796 if (handle == 0) { 797 handle = qdisc_alloc_handle(dev); 798 err = -ENOMEM; 799 if (handle == 0) 800 goto err_out3; 801 } 802 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock); 803 } 804 805 sch->handle = handle; 806 807 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) { 808 if (tca[TCA_STAB]) { 809 stab = qdisc_get_stab(tca[TCA_STAB]); 810 if (IS_ERR(stab)) { 811 err = PTR_ERR(stab); 812 goto err_out4; 813 } 814 sch->stab = stab; 815 } 816 if (tca[TCA_RATE]) { 817 spinlock_t *root_lock; 818 819 err = -EOPNOTSUPP; 820 if (sch->flags & TCQ_F_MQROOT) 821 goto err_out4; 822 823 if ((sch->parent != TC_H_ROOT) && 824 !(sch->flags & TCQ_F_INGRESS) && 825 (!p || !(p->flags & TCQ_F_MQROOT))) 826 root_lock = qdisc_root_sleeping_lock(sch); 827 else 828 root_lock = qdisc_lock(sch); 829 830 err = gen_new_estimator(&sch->bstats, &sch->rate_est, 831 root_lock, tca[TCA_RATE]); 832 if (err) 833 goto err_out4; 834 } 835 836 qdisc_list_add(sch); 837 838 return sch; 839 } 840 err_out3: 841 dev_put(dev); 842 kfree((char *) sch - sch->padded); 843 err_out2: 844 module_put(ops->owner); 845 err_out: 846 *errp = err; 847 return NULL; 848 849 err_out4: 850 /* 851 * Any broken qdiscs that would require a ops->reset() here? 852 * The qdisc was never in action so it shouldn't be necessary. 853 */ 854 qdisc_put_stab(sch->stab); 855 if (ops->destroy) 856 ops->destroy(sch); 857 goto err_out3; 858 } 859 860 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca) 861 { 862 struct qdisc_size_table *stab = NULL; 863 int err = 0; 864 865 if (tca[TCA_OPTIONS]) { 866 if (sch->ops->change == NULL) 867 return -EINVAL; 868 err = sch->ops->change(sch, tca[TCA_OPTIONS]); 869 if (err) 870 return err; 871 } 872 873 if (tca[TCA_STAB]) { 874 stab = qdisc_get_stab(tca[TCA_STAB]); 875 if (IS_ERR(stab)) 876 return PTR_ERR(stab); 877 } 878 879 qdisc_put_stab(sch->stab); 880 sch->stab = stab; 881 882 if (tca[TCA_RATE]) { 883 /* NB: ignores errors from replace_estimator 884 because change can't be undone. */ 885 if (sch->flags & TCQ_F_MQROOT) 886 goto out; 887 gen_replace_estimator(&sch->bstats, &sch->rate_est, 888 qdisc_root_sleeping_lock(sch), 889 tca[TCA_RATE]); 890 } 891 out: 892 return 0; 893 } 894 895 struct check_loop_arg 896 { 897 struct qdisc_walker w; 898 struct Qdisc *p; 899 int depth; 900 }; 901 902 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w); 903 904 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 905 { 906 struct check_loop_arg arg; 907 908 if (q->ops->cl_ops == NULL) 909 return 0; 910 911 arg.w.stop = arg.w.skip = arg.w.count = 0; 912 arg.w.fn = check_loop_fn; 913 arg.depth = depth; 914 arg.p = p; 915 q->ops->cl_ops->walk(q, &arg.w); 916 return arg.w.stop ? -ELOOP : 0; 917 } 918 919 static int 920 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 921 { 922 struct Qdisc *leaf; 923 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 924 struct check_loop_arg *arg = (struct check_loop_arg *)w; 925 926 leaf = cops->leaf(q, cl); 927 if (leaf) { 928 if (leaf == arg->p || arg->depth > 7) 929 return -ELOOP; 930 return check_loop(leaf, arg->p, arg->depth + 1); 931 } 932 return 0; 933 } 934 935 /* 936 * Delete/get qdisc. 937 */ 938 939 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 940 { 941 struct net *net = sock_net(skb->sk); 942 struct tcmsg *tcm = NLMSG_DATA(n); 943 struct nlattr *tca[TCA_MAX + 1]; 944 struct net_device *dev; 945 u32 clid = tcm->tcm_parent; 946 struct Qdisc *q = NULL; 947 struct Qdisc *p = NULL; 948 int err; 949 950 if (net != &init_net) 951 return -EINVAL; 952 953 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 954 return -ENODEV; 955 956 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 957 if (err < 0) 958 return err; 959 960 if (clid) { 961 if (clid != TC_H_ROOT) { 962 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 963 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 964 return -ENOENT; 965 q = qdisc_leaf(p, clid); 966 } else { /* ingress */ 967 q = dev->rx_queue.qdisc_sleeping; 968 } 969 } else { 970 q = dev->qdisc; 971 } 972 if (!q) 973 return -ENOENT; 974 975 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) 976 return -EINVAL; 977 } else { 978 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 979 return -ENOENT; 980 } 981 982 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 983 return -EINVAL; 984 985 if (n->nlmsg_type == RTM_DELQDISC) { 986 if (!clid) 987 return -EINVAL; 988 if (q->handle == 0) 989 return -ENOENT; 990 if ((err = qdisc_graft(dev, p, skb, n, clid, NULL, q)) != 0) 991 return err; 992 } else { 993 qdisc_notify(skb, n, clid, NULL, q); 994 } 995 return 0; 996 } 997 998 /* 999 Create/change qdisc. 1000 */ 1001 1002 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1003 { 1004 struct net *net = sock_net(skb->sk); 1005 struct tcmsg *tcm; 1006 struct nlattr *tca[TCA_MAX + 1]; 1007 struct net_device *dev; 1008 u32 clid; 1009 struct Qdisc *q, *p; 1010 int err; 1011 1012 if (net != &init_net) 1013 return -EINVAL; 1014 1015 replay: 1016 /* Reinit, just in case something touches this. */ 1017 tcm = NLMSG_DATA(n); 1018 clid = tcm->tcm_parent; 1019 q = p = NULL; 1020 1021 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1022 return -ENODEV; 1023 1024 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1025 if (err < 0) 1026 return err; 1027 1028 if (clid) { 1029 if (clid != TC_H_ROOT) { 1030 if (clid != TC_H_INGRESS) { 1031 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 1032 return -ENOENT; 1033 q = qdisc_leaf(p, clid); 1034 } else { /*ingress */ 1035 q = dev->rx_queue.qdisc_sleeping; 1036 } 1037 } else { 1038 q = dev->qdisc; 1039 } 1040 1041 /* It may be default qdisc, ignore it */ 1042 if (q && q->handle == 0) 1043 q = NULL; 1044 1045 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1046 if (tcm->tcm_handle) { 1047 if (q && !(n->nlmsg_flags&NLM_F_REPLACE)) 1048 return -EEXIST; 1049 if (TC_H_MIN(tcm->tcm_handle)) 1050 return -EINVAL; 1051 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 1052 goto create_n_graft; 1053 if (n->nlmsg_flags&NLM_F_EXCL) 1054 return -EEXIST; 1055 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1056 return -EINVAL; 1057 if (q == p || 1058 (p && check_loop(q, p, 0))) 1059 return -ELOOP; 1060 atomic_inc(&q->refcnt); 1061 goto graft; 1062 } else { 1063 if (q == NULL) 1064 goto create_n_graft; 1065 1066 /* This magic test requires explanation. 1067 * 1068 * We know, that some child q is already 1069 * attached to this parent and have choice: 1070 * either to change it or to create/graft new one. 1071 * 1072 * 1. We are allowed to create/graft only 1073 * if CREATE and REPLACE flags are set. 1074 * 1075 * 2. If EXCL is set, requestor wanted to say, 1076 * that qdisc tcm_handle is not expected 1077 * to exist, so that we choose create/graft too. 1078 * 1079 * 3. The last case is when no flags are set. 1080 * Alas, it is sort of hole in API, we 1081 * cannot decide what to do unambiguously. 1082 * For now we select create/graft, if 1083 * user gave KIND, which does not match existing. 1084 */ 1085 if ((n->nlmsg_flags&NLM_F_CREATE) && 1086 (n->nlmsg_flags&NLM_F_REPLACE) && 1087 ((n->nlmsg_flags&NLM_F_EXCL) || 1088 (tca[TCA_KIND] && 1089 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1090 goto create_n_graft; 1091 } 1092 } 1093 } else { 1094 if (!tcm->tcm_handle) 1095 return -EINVAL; 1096 q = qdisc_lookup(dev, tcm->tcm_handle); 1097 } 1098 1099 /* Change qdisc parameters */ 1100 if (q == NULL) 1101 return -ENOENT; 1102 if (n->nlmsg_flags&NLM_F_EXCL) 1103 return -EEXIST; 1104 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1105 return -EINVAL; 1106 err = qdisc_change(q, tca); 1107 if (err == 0) 1108 qdisc_notify(skb, n, clid, NULL, q); 1109 return err; 1110 1111 create_n_graft: 1112 if (!(n->nlmsg_flags&NLM_F_CREATE)) 1113 return -ENOENT; 1114 if (clid == TC_H_INGRESS) 1115 q = qdisc_create(dev, &dev->rx_queue, p, 1116 tcm->tcm_parent, tcm->tcm_parent, 1117 tca, &err); 1118 else { 1119 struct netdev_queue *dev_queue; 1120 1121 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1122 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1123 else if (p) 1124 dev_queue = p->dev_queue; 1125 else 1126 dev_queue = netdev_get_tx_queue(dev, 0); 1127 1128 q = qdisc_create(dev, dev_queue, p, 1129 tcm->tcm_parent, tcm->tcm_handle, 1130 tca, &err); 1131 } 1132 if (q == NULL) { 1133 if (err == -EAGAIN) 1134 goto replay; 1135 return err; 1136 } 1137 1138 graft: 1139 err = qdisc_graft(dev, p, skb, n, clid, q, NULL); 1140 if (err) { 1141 if (q) 1142 qdisc_destroy(q); 1143 return err; 1144 } 1145 1146 return 0; 1147 } 1148 1149 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 1150 u32 pid, u32 seq, u16 flags, int event) 1151 { 1152 struct tcmsg *tcm; 1153 struct nlmsghdr *nlh; 1154 unsigned char *b = skb_tail_pointer(skb); 1155 struct gnet_dump d; 1156 1157 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1158 tcm = NLMSG_DATA(nlh); 1159 tcm->tcm_family = AF_UNSPEC; 1160 tcm->tcm__pad1 = 0; 1161 tcm->tcm__pad2 = 0; 1162 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1163 tcm->tcm_parent = clid; 1164 tcm->tcm_handle = q->handle; 1165 tcm->tcm_info = atomic_read(&q->refcnt); 1166 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1167 if (q->ops->dump && q->ops->dump(q, skb) < 0) 1168 goto nla_put_failure; 1169 q->qstats.qlen = q->q.qlen; 1170 1171 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0) 1172 goto nla_put_failure; 1173 1174 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1175 qdisc_root_sleeping_lock(q), &d) < 0) 1176 goto nla_put_failure; 1177 1178 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 1179 goto nla_put_failure; 1180 1181 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 || 1182 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 1183 gnet_stats_copy_queue(&d, &q->qstats) < 0) 1184 goto nla_put_failure; 1185 1186 if (gnet_stats_finish_copy(&d) < 0) 1187 goto nla_put_failure; 1188 1189 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1190 return skb->len; 1191 1192 nlmsg_failure: 1193 nla_put_failure: 1194 nlmsg_trim(skb, b); 1195 return -1; 1196 } 1197 1198 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1199 u32 clid, struct Qdisc *old, struct Qdisc *new) 1200 { 1201 struct sk_buff *skb; 1202 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1203 1204 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1205 if (!skb) 1206 return -ENOBUFS; 1207 1208 if (old && old->handle) { 1209 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0) 1210 goto err_out; 1211 } 1212 if (new) { 1213 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1214 goto err_out; 1215 } 1216 1217 if (skb->len) 1218 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1219 1220 err_out: 1221 kfree_skb(skb); 1222 return -EINVAL; 1223 } 1224 1225 static bool tc_qdisc_dump_ignore(struct Qdisc *q) 1226 { 1227 return (q->flags & TCQ_F_BUILTIN) ? true : false; 1228 } 1229 1230 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1231 struct netlink_callback *cb, 1232 int *q_idx_p, int s_q_idx) 1233 { 1234 int ret = 0, q_idx = *q_idx_p; 1235 struct Qdisc *q; 1236 1237 if (!root) 1238 return 0; 1239 1240 q = root; 1241 if (q_idx < s_q_idx) { 1242 q_idx++; 1243 } else { 1244 if (!tc_qdisc_dump_ignore(q) && 1245 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1246 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1247 goto done; 1248 q_idx++; 1249 } 1250 list_for_each_entry(q, &root->list, list) { 1251 if (q_idx < s_q_idx) { 1252 q_idx++; 1253 continue; 1254 } 1255 if (!tc_qdisc_dump_ignore(q) && 1256 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1257 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1258 goto done; 1259 q_idx++; 1260 } 1261 1262 out: 1263 *q_idx_p = q_idx; 1264 return ret; 1265 done: 1266 ret = -1; 1267 goto out; 1268 } 1269 1270 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1271 { 1272 struct net *net = sock_net(skb->sk); 1273 int idx, q_idx; 1274 int s_idx, s_q_idx; 1275 struct net_device *dev; 1276 1277 if (net != &init_net) 1278 return 0; 1279 1280 s_idx = cb->args[0]; 1281 s_q_idx = q_idx = cb->args[1]; 1282 read_lock(&dev_base_lock); 1283 idx = 0; 1284 for_each_netdev(&init_net, dev) { 1285 struct netdev_queue *dev_queue; 1286 1287 if (idx < s_idx) 1288 goto cont; 1289 if (idx > s_idx) 1290 s_q_idx = 0; 1291 q_idx = 0; 1292 1293 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0) 1294 goto done; 1295 1296 dev_queue = &dev->rx_queue; 1297 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1298 goto done; 1299 1300 cont: 1301 idx++; 1302 } 1303 1304 done: 1305 read_unlock(&dev_base_lock); 1306 1307 cb->args[0] = idx; 1308 cb->args[1] = q_idx; 1309 1310 return skb->len; 1311 } 1312 1313 1314 1315 /************************************************ 1316 * Traffic classes manipulation. * 1317 ************************************************/ 1318 1319 1320 1321 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1322 { 1323 struct net *net = sock_net(skb->sk); 1324 struct tcmsg *tcm = NLMSG_DATA(n); 1325 struct nlattr *tca[TCA_MAX + 1]; 1326 struct net_device *dev; 1327 struct Qdisc *q = NULL; 1328 const struct Qdisc_class_ops *cops; 1329 unsigned long cl = 0; 1330 unsigned long new_cl; 1331 u32 pid = tcm->tcm_parent; 1332 u32 clid = tcm->tcm_handle; 1333 u32 qid = TC_H_MAJ(clid); 1334 int err; 1335 1336 if (net != &init_net) 1337 return -EINVAL; 1338 1339 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1340 return -ENODEV; 1341 1342 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1343 if (err < 0) 1344 return err; 1345 1346 /* 1347 parent == TC_H_UNSPEC - unspecified parent. 1348 parent == TC_H_ROOT - class is root, which has no parent. 1349 parent == X:0 - parent is root class. 1350 parent == X:Y - parent is a node in hierarchy. 1351 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 1352 1353 handle == 0:0 - generate handle from kernel pool. 1354 handle == 0:Y - class is X:Y, where X:0 is qdisc. 1355 handle == X:Y - clear. 1356 handle == X:0 - root class. 1357 */ 1358 1359 /* Step 1. Determine qdisc handle X:0 */ 1360 1361 if (pid != TC_H_ROOT) { 1362 u32 qid1 = TC_H_MAJ(pid); 1363 1364 if (qid && qid1) { 1365 /* If both majors are known, they must be identical. */ 1366 if (qid != qid1) 1367 return -EINVAL; 1368 } else if (qid1) { 1369 qid = qid1; 1370 } else if (qid == 0) 1371 qid = dev->qdisc->handle; 1372 1373 /* Now qid is genuine qdisc handle consistent 1374 both with parent and child. 1375 1376 TC_H_MAJ(pid) still may be unspecified, complete it now. 1377 */ 1378 if (pid) 1379 pid = TC_H_MAKE(qid, pid); 1380 } else { 1381 if (qid == 0) 1382 qid = dev->qdisc->handle; 1383 } 1384 1385 /* OK. Locate qdisc */ 1386 if ((q = qdisc_lookup(dev, qid)) == NULL) 1387 return -ENOENT; 1388 1389 /* An check that it supports classes */ 1390 cops = q->ops->cl_ops; 1391 if (cops == NULL) 1392 return -EINVAL; 1393 1394 /* Now try to get class */ 1395 if (clid == 0) { 1396 if (pid == TC_H_ROOT) 1397 clid = qid; 1398 } else 1399 clid = TC_H_MAKE(qid, clid); 1400 1401 if (clid) 1402 cl = cops->get(q, clid); 1403 1404 if (cl == 0) { 1405 err = -ENOENT; 1406 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE)) 1407 goto out; 1408 } else { 1409 switch (n->nlmsg_type) { 1410 case RTM_NEWTCLASS: 1411 err = -EEXIST; 1412 if (n->nlmsg_flags&NLM_F_EXCL) 1413 goto out; 1414 break; 1415 case RTM_DELTCLASS: 1416 err = -EOPNOTSUPP; 1417 if (cops->delete) 1418 err = cops->delete(q, cl); 1419 if (err == 0) 1420 tclass_notify(skb, n, q, cl, RTM_DELTCLASS); 1421 goto out; 1422 case RTM_GETTCLASS: 1423 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS); 1424 goto out; 1425 default: 1426 err = -EINVAL; 1427 goto out; 1428 } 1429 } 1430 1431 new_cl = cl; 1432 err = -EOPNOTSUPP; 1433 if (cops->change) 1434 err = cops->change(q, clid, pid, tca, &new_cl); 1435 if (err == 0) 1436 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS); 1437 1438 out: 1439 if (cl) 1440 cops->put(q, cl); 1441 1442 return err; 1443 } 1444 1445 1446 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1447 unsigned long cl, 1448 u32 pid, u32 seq, u16 flags, int event) 1449 { 1450 struct tcmsg *tcm; 1451 struct nlmsghdr *nlh; 1452 unsigned char *b = skb_tail_pointer(skb); 1453 struct gnet_dump d; 1454 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1455 1456 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1457 tcm = NLMSG_DATA(nlh); 1458 tcm->tcm_family = AF_UNSPEC; 1459 tcm->tcm__pad1 = 0; 1460 tcm->tcm__pad2 = 0; 1461 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1462 tcm->tcm_parent = q->handle; 1463 tcm->tcm_handle = q->handle; 1464 tcm->tcm_info = 0; 1465 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1466 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1467 goto nla_put_failure; 1468 1469 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1470 qdisc_root_sleeping_lock(q), &d) < 0) 1471 goto nla_put_failure; 1472 1473 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1474 goto nla_put_failure; 1475 1476 if (gnet_stats_finish_copy(&d) < 0) 1477 goto nla_put_failure; 1478 1479 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1480 return skb->len; 1481 1482 nlmsg_failure: 1483 nla_put_failure: 1484 nlmsg_trim(skb, b); 1485 return -1; 1486 } 1487 1488 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1489 struct Qdisc *q, unsigned long cl, int event) 1490 { 1491 struct sk_buff *skb; 1492 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1493 1494 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1495 if (!skb) 1496 return -ENOBUFS; 1497 1498 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) { 1499 kfree_skb(skb); 1500 return -EINVAL; 1501 } 1502 1503 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1504 } 1505 1506 struct qdisc_dump_args 1507 { 1508 struct qdisc_walker w; 1509 struct sk_buff *skb; 1510 struct netlink_callback *cb; 1511 }; 1512 1513 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg) 1514 { 1515 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 1516 1517 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid, 1518 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS); 1519 } 1520 1521 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 1522 struct tcmsg *tcm, struct netlink_callback *cb, 1523 int *t_p, int s_t) 1524 { 1525 struct qdisc_dump_args arg; 1526 1527 if (tc_qdisc_dump_ignore(q) || 1528 *t_p < s_t || !q->ops->cl_ops || 1529 (tcm->tcm_parent && 1530 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 1531 (*t_p)++; 1532 return 0; 1533 } 1534 if (*t_p > s_t) 1535 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 1536 arg.w.fn = qdisc_class_dump; 1537 arg.skb = skb; 1538 arg.cb = cb; 1539 arg.w.stop = 0; 1540 arg.w.skip = cb->args[1]; 1541 arg.w.count = 0; 1542 q->ops->cl_ops->walk(q, &arg.w); 1543 cb->args[1] = arg.w.count; 1544 if (arg.w.stop) 1545 return -1; 1546 (*t_p)++; 1547 return 0; 1548 } 1549 1550 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 1551 struct tcmsg *tcm, struct netlink_callback *cb, 1552 int *t_p, int s_t) 1553 { 1554 struct Qdisc *q; 1555 1556 if (!root) 1557 return 0; 1558 1559 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 1560 return -1; 1561 1562 list_for_each_entry(q, &root->list, list) { 1563 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 1564 return -1; 1565 } 1566 1567 return 0; 1568 } 1569 1570 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 1571 { 1572 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh); 1573 struct net *net = sock_net(skb->sk); 1574 struct netdev_queue *dev_queue; 1575 struct net_device *dev; 1576 int t, s_t; 1577 1578 if (net != &init_net) 1579 return 0; 1580 1581 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm))) 1582 return 0; 1583 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1584 return 0; 1585 1586 s_t = cb->args[0]; 1587 t = 0; 1588 1589 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0) 1590 goto done; 1591 1592 dev_queue = &dev->rx_queue; 1593 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1594 goto done; 1595 1596 done: 1597 cb->args[0] = t; 1598 1599 dev_put(dev); 1600 return skb->len; 1601 } 1602 1603 /* Main classifier routine: scans classifier chain attached 1604 to this qdisc, (optionally) tests for protocol and asks 1605 specific classifiers. 1606 */ 1607 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp, 1608 struct tcf_result *res) 1609 { 1610 __be16 protocol = skb->protocol; 1611 int err = 0; 1612 1613 for (; tp; tp = tp->next) { 1614 if ((tp->protocol == protocol || 1615 tp->protocol == htons(ETH_P_ALL)) && 1616 (err = tp->classify(skb, tp, res)) >= 0) { 1617 #ifdef CONFIG_NET_CLS_ACT 1618 if (err != TC_ACT_RECLASSIFY && skb->tc_verd) 1619 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0); 1620 #endif 1621 return err; 1622 } 1623 } 1624 return -1; 1625 } 1626 EXPORT_SYMBOL(tc_classify_compat); 1627 1628 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp, 1629 struct tcf_result *res) 1630 { 1631 int err = 0; 1632 __be16 protocol; 1633 #ifdef CONFIG_NET_CLS_ACT 1634 struct tcf_proto *otp = tp; 1635 reclassify: 1636 #endif 1637 protocol = skb->protocol; 1638 1639 err = tc_classify_compat(skb, tp, res); 1640 #ifdef CONFIG_NET_CLS_ACT 1641 if (err == TC_ACT_RECLASSIFY) { 1642 u32 verd = G_TC_VERD(skb->tc_verd); 1643 tp = otp; 1644 1645 if (verd++ >= MAX_REC_LOOP) { 1646 printk("rule prio %u protocol %02x reclassify loop, " 1647 "packet dropped\n", 1648 tp->prio&0xffff, ntohs(tp->protocol)); 1649 return TC_ACT_SHOT; 1650 } 1651 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd); 1652 goto reclassify; 1653 } 1654 #endif 1655 return err; 1656 } 1657 EXPORT_SYMBOL(tc_classify); 1658 1659 void tcf_destroy(struct tcf_proto *tp) 1660 { 1661 tp->ops->destroy(tp); 1662 module_put(tp->ops->owner); 1663 kfree(tp); 1664 } 1665 1666 void tcf_destroy_chain(struct tcf_proto **fl) 1667 { 1668 struct tcf_proto *tp; 1669 1670 while ((tp = *fl) != NULL) { 1671 *fl = tp->next; 1672 tcf_destroy(tp); 1673 } 1674 } 1675 EXPORT_SYMBOL(tcf_destroy_chain); 1676 1677 #ifdef CONFIG_PROC_FS 1678 static int psched_show(struct seq_file *seq, void *v) 1679 { 1680 struct timespec ts; 1681 1682 hrtimer_get_res(CLOCK_MONOTONIC, &ts); 1683 seq_printf(seq, "%08x %08x %08x %08x\n", 1684 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 1685 1000000, 1686 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts))); 1687 1688 return 0; 1689 } 1690 1691 static int psched_open(struct inode *inode, struct file *file) 1692 { 1693 return single_open(file, psched_show, PDE(inode)->data); 1694 } 1695 1696 static const struct file_operations psched_fops = { 1697 .owner = THIS_MODULE, 1698 .open = psched_open, 1699 .read = seq_read, 1700 .llseek = seq_lseek, 1701 .release = single_release, 1702 }; 1703 #endif 1704 1705 static int __init pktsched_init(void) 1706 { 1707 register_qdisc(&pfifo_qdisc_ops); 1708 register_qdisc(&bfifo_qdisc_ops); 1709 register_qdisc(&mq_qdisc_ops); 1710 proc_net_fops_create(&init_net, "psched", 0, &psched_fops); 1711 1712 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL); 1713 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL); 1714 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc); 1715 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL); 1716 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL); 1717 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass); 1718 1719 return 0; 1720 } 1721 1722 subsys_initcall(pktsched_init); 1723