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 qdisc_destroy(old); 697 } 698 699 notify_and_destroy(skb, n, classid, dev->qdisc, new); 700 if (new && !new->ops->attach) 701 atomic_inc(&new->refcnt); 702 dev->qdisc = new ? : &noop_qdisc; 703 704 if (dev->flags & IFF_UP) 705 dev_activate(dev); 706 } else { 707 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 708 709 err = -EOPNOTSUPP; 710 if (cops && cops->graft) { 711 unsigned long cl = cops->get(parent, classid); 712 if (cl) { 713 err = cops->graft(parent, cl, new, &old); 714 cops->put(parent, cl); 715 } else 716 err = -ENOENT; 717 } 718 if (!err) 719 notify_and_destroy(skb, n, classid, old, new); 720 } 721 return err; 722 } 723 724 /* lockdep annotation is needed for ingress; egress gets it only for name */ 725 static struct lock_class_key qdisc_tx_lock; 726 static struct lock_class_key qdisc_rx_lock; 727 728 /* 729 Allocate and initialize new qdisc. 730 731 Parameters are passed via opt. 732 */ 733 734 static struct Qdisc * 735 qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue, 736 u32 parent, u32 handle, struct nlattr **tca, int *errp) 737 { 738 int err; 739 struct nlattr *kind = tca[TCA_KIND]; 740 struct Qdisc *sch; 741 struct Qdisc_ops *ops; 742 struct qdisc_size_table *stab; 743 744 ops = qdisc_lookup_ops(kind); 745 #ifdef CONFIG_MODULES 746 if (ops == NULL && kind != NULL) { 747 char name[IFNAMSIZ]; 748 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) { 749 /* We dropped the RTNL semaphore in order to 750 * perform the module load. So, even if we 751 * succeeded in loading the module we have to 752 * tell the caller to replay the request. We 753 * indicate this using -EAGAIN. 754 * We replay the request because the device may 755 * go away in the mean time. 756 */ 757 rtnl_unlock(); 758 request_module("sch_%s", name); 759 rtnl_lock(); 760 ops = qdisc_lookup_ops(kind); 761 if (ops != NULL) { 762 /* We will try again qdisc_lookup_ops, 763 * so don't keep a reference. 764 */ 765 module_put(ops->owner); 766 err = -EAGAIN; 767 goto err_out; 768 } 769 } 770 } 771 #endif 772 773 err = -ENOENT; 774 if (ops == NULL) 775 goto err_out; 776 777 sch = qdisc_alloc(dev_queue, ops); 778 if (IS_ERR(sch)) { 779 err = PTR_ERR(sch); 780 goto err_out2; 781 } 782 783 sch->parent = parent; 784 785 if (handle == TC_H_INGRESS) { 786 sch->flags |= TCQ_F_INGRESS; 787 handle = TC_H_MAKE(TC_H_INGRESS, 0); 788 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock); 789 } else { 790 if (handle == 0) { 791 handle = qdisc_alloc_handle(dev); 792 err = -ENOMEM; 793 if (handle == 0) 794 goto err_out3; 795 } 796 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock); 797 } 798 799 sch->handle = handle; 800 801 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) { 802 if (tca[TCA_STAB]) { 803 stab = qdisc_get_stab(tca[TCA_STAB]); 804 if (IS_ERR(stab)) { 805 err = PTR_ERR(stab); 806 goto err_out3; 807 } 808 sch->stab = stab; 809 } 810 if (tca[TCA_RATE]) { 811 spinlock_t *root_lock; 812 813 if ((sch->parent != TC_H_ROOT) && 814 !(sch->flags & TCQ_F_INGRESS)) 815 root_lock = qdisc_root_sleeping_lock(sch); 816 else 817 root_lock = qdisc_lock(sch); 818 819 err = gen_new_estimator(&sch->bstats, &sch->rate_est, 820 root_lock, tca[TCA_RATE]); 821 if (err) { 822 /* 823 * Any broken qdiscs that would require 824 * a ops->reset() here? The qdisc was never 825 * in action so it shouldn't be necessary. 826 */ 827 if (ops->destroy) 828 ops->destroy(sch); 829 goto err_out3; 830 } 831 } 832 833 qdisc_list_add(sch); 834 835 return sch; 836 } 837 err_out3: 838 qdisc_put_stab(sch->stab); 839 dev_put(dev); 840 kfree((char *) sch - sch->padded); 841 err_out2: 842 module_put(ops->owner); 843 err_out: 844 *errp = err; 845 return NULL; 846 } 847 848 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca) 849 { 850 struct qdisc_size_table *stab = NULL; 851 int err = 0; 852 853 if (tca[TCA_OPTIONS]) { 854 if (sch->ops->change == NULL) 855 return -EINVAL; 856 err = sch->ops->change(sch, tca[TCA_OPTIONS]); 857 if (err) 858 return err; 859 } 860 861 if (tca[TCA_STAB]) { 862 stab = qdisc_get_stab(tca[TCA_STAB]); 863 if (IS_ERR(stab)) 864 return PTR_ERR(stab); 865 } 866 867 qdisc_put_stab(sch->stab); 868 sch->stab = stab; 869 870 if (tca[TCA_RATE]) 871 /* NB: ignores errors from replace_estimator 872 because change can't be undone. */ 873 gen_replace_estimator(&sch->bstats, &sch->rate_est, 874 qdisc_root_sleeping_lock(sch), 875 tca[TCA_RATE]); 876 877 return 0; 878 } 879 880 struct check_loop_arg 881 { 882 struct qdisc_walker w; 883 struct Qdisc *p; 884 int depth; 885 }; 886 887 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w); 888 889 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 890 { 891 struct check_loop_arg arg; 892 893 if (q->ops->cl_ops == NULL) 894 return 0; 895 896 arg.w.stop = arg.w.skip = arg.w.count = 0; 897 arg.w.fn = check_loop_fn; 898 arg.depth = depth; 899 arg.p = p; 900 q->ops->cl_ops->walk(q, &arg.w); 901 return arg.w.stop ? -ELOOP : 0; 902 } 903 904 static int 905 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 906 { 907 struct Qdisc *leaf; 908 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 909 struct check_loop_arg *arg = (struct check_loop_arg *)w; 910 911 leaf = cops->leaf(q, cl); 912 if (leaf) { 913 if (leaf == arg->p || arg->depth > 7) 914 return -ELOOP; 915 return check_loop(leaf, arg->p, arg->depth + 1); 916 } 917 return 0; 918 } 919 920 /* 921 * Delete/get qdisc. 922 */ 923 924 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 925 { 926 struct net *net = sock_net(skb->sk); 927 struct tcmsg *tcm = NLMSG_DATA(n); 928 struct nlattr *tca[TCA_MAX + 1]; 929 struct net_device *dev; 930 u32 clid = tcm->tcm_parent; 931 struct Qdisc *q = NULL; 932 struct Qdisc *p = NULL; 933 int err; 934 935 if (net != &init_net) 936 return -EINVAL; 937 938 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 939 return -ENODEV; 940 941 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 942 if (err < 0) 943 return err; 944 945 if (clid) { 946 if (clid != TC_H_ROOT) { 947 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 948 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 949 return -ENOENT; 950 q = qdisc_leaf(p, clid); 951 } else { /* ingress */ 952 q = dev->rx_queue.qdisc_sleeping; 953 } 954 } else { 955 q = dev->qdisc; 956 } 957 if (!q) 958 return -ENOENT; 959 960 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) 961 return -EINVAL; 962 } else { 963 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 964 return -ENOENT; 965 } 966 967 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 968 return -EINVAL; 969 970 if (n->nlmsg_type == RTM_DELQDISC) { 971 if (!clid) 972 return -EINVAL; 973 if (q->handle == 0) 974 return -ENOENT; 975 if ((err = qdisc_graft(dev, p, skb, n, clid, NULL, q)) != 0) 976 return err; 977 } else { 978 qdisc_notify(skb, n, clid, NULL, q); 979 } 980 return 0; 981 } 982 983 /* 984 Create/change qdisc. 985 */ 986 987 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 988 { 989 struct net *net = sock_net(skb->sk); 990 struct tcmsg *tcm; 991 struct nlattr *tca[TCA_MAX + 1]; 992 struct net_device *dev; 993 u32 clid; 994 struct Qdisc *q, *p; 995 int err; 996 997 if (net != &init_net) 998 return -EINVAL; 999 1000 replay: 1001 /* Reinit, just in case something touches this. */ 1002 tcm = NLMSG_DATA(n); 1003 clid = tcm->tcm_parent; 1004 q = p = NULL; 1005 1006 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1007 return -ENODEV; 1008 1009 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1010 if (err < 0) 1011 return err; 1012 1013 if (clid) { 1014 if (clid != TC_H_ROOT) { 1015 if (clid != TC_H_INGRESS) { 1016 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 1017 return -ENOENT; 1018 q = qdisc_leaf(p, clid); 1019 } else { /*ingress */ 1020 q = dev->rx_queue.qdisc_sleeping; 1021 } 1022 } else { 1023 q = dev->qdisc; 1024 } 1025 1026 /* It may be default qdisc, ignore it */ 1027 if (q && q->handle == 0) 1028 q = NULL; 1029 1030 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1031 if (tcm->tcm_handle) { 1032 if (q && !(n->nlmsg_flags&NLM_F_REPLACE)) 1033 return -EEXIST; 1034 if (TC_H_MIN(tcm->tcm_handle)) 1035 return -EINVAL; 1036 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 1037 goto create_n_graft; 1038 if (n->nlmsg_flags&NLM_F_EXCL) 1039 return -EEXIST; 1040 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1041 return -EINVAL; 1042 if (q == p || 1043 (p && check_loop(q, p, 0))) 1044 return -ELOOP; 1045 atomic_inc(&q->refcnt); 1046 goto graft; 1047 } else { 1048 if (q == NULL) 1049 goto create_n_graft; 1050 1051 /* This magic test requires explanation. 1052 * 1053 * We know, that some child q is already 1054 * attached to this parent and have choice: 1055 * either to change it or to create/graft new one. 1056 * 1057 * 1. We are allowed to create/graft only 1058 * if CREATE and REPLACE flags are set. 1059 * 1060 * 2. If EXCL is set, requestor wanted to say, 1061 * that qdisc tcm_handle is not expected 1062 * to exist, so that we choose create/graft too. 1063 * 1064 * 3. The last case is when no flags are set. 1065 * Alas, it is sort of hole in API, we 1066 * cannot decide what to do unambiguously. 1067 * For now we select create/graft, if 1068 * user gave KIND, which does not match existing. 1069 */ 1070 if ((n->nlmsg_flags&NLM_F_CREATE) && 1071 (n->nlmsg_flags&NLM_F_REPLACE) && 1072 ((n->nlmsg_flags&NLM_F_EXCL) || 1073 (tca[TCA_KIND] && 1074 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1075 goto create_n_graft; 1076 } 1077 } 1078 } else { 1079 if (!tcm->tcm_handle) 1080 return -EINVAL; 1081 q = qdisc_lookup(dev, tcm->tcm_handle); 1082 } 1083 1084 /* Change qdisc parameters */ 1085 if (q == NULL) 1086 return -ENOENT; 1087 if (n->nlmsg_flags&NLM_F_EXCL) 1088 return -EEXIST; 1089 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1090 return -EINVAL; 1091 err = qdisc_change(q, tca); 1092 if (err == 0) 1093 qdisc_notify(skb, n, clid, NULL, q); 1094 return err; 1095 1096 create_n_graft: 1097 if (!(n->nlmsg_flags&NLM_F_CREATE)) 1098 return -ENOENT; 1099 if (clid == TC_H_INGRESS) 1100 q = qdisc_create(dev, &dev->rx_queue, 1101 tcm->tcm_parent, tcm->tcm_parent, 1102 tca, &err); 1103 else { 1104 unsigned int ntx = 0; 1105 1106 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1107 ntx = p->ops->cl_ops->select_queue(p, tcm); 1108 1109 q = qdisc_create(dev, netdev_get_tx_queue(dev, ntx), 1110 tcm->tcm_parent, tcm->tcm_handle, 1111 tca, &err); 1112 } 1113 if (q == NULL) { 1114 if (err == -EAGAIN) 1115 goto replay; 1116 return err; 1117 } 1118 1119 graft: 1120 err = qdisc_graft(dev, p, skb, n, clid, q, NULL); 1121 if (err) { 1122 if (q) 1123 qdisc_destroy(q); 1124 return err; 1125 } 1126 1127 return 0; 1128 } 1129 1130 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 1131 u32 pid, u32 seq, u16 flags, int event) 1132 { 1133 struct tcmsg *tcm; 1134 struct nlmsghdr *nlh; 1135 unsigned char *b = skb_tail_pointer(skb); 1136 struct gnet_dump d; 1137 1138 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1139 tcm = NLMSG_DATA(nlh); 1140 tcm->tcm_family = AF_UNSPEC; 1141 tcm->tcm__pad1 = 0; 1142 tcm->tcm__pad2 = 0; 1143 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1144 tcm->tcm_parent = clid; 1145 tcm->tcm_handle = q->handle; 1146 tcm->tcm_info = atomic_read(&q->refcnt); 1147 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1148 if (q->ops->dump && q->ops->dump(q, skb) < 0) 1149 goto nla_put_failure; 1150 q->qstats.qlen = q->q.qlen; 1151 1152 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0) 1153 goto nla_put_failure; 1154 1155 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1156 qdisc_root_sleeping_lock(q), &d) < 0) 1157 goto nla_put_failure; 1158 1159 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 1160 goto nla_put_failure; 1161 1162 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 || 1163 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 1164 gnet_stats_copy_queue(&d, &q->qstats) < 0) 1165 goto nla_put_failure; 1166 1167 if (gnet_stats_finish_copy(&d) < 0) 1168 goto nla_put_failure; 1169 1170 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1171 return skb->len; 1172 1173 nlmsg_failure: 1174 nla_put_failure: 1175 nlmsg_trim(skb, b); 1176 return -1; 1177 } 1178 1179 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1180 u32 clid, struct Qdisc *old, struct Qdisc *new) 1181 { 1182 struct sk_buff *skb; 1183 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1184 1185 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1186 if (!skb) 1187 return -ENOBUFS; 1188 1189 if (old && old->handle) { 1190 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0) 1191 goto err_out; 1192 } 1193 if (new) { 1194 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1195 goto err_out; 1196 } 1197 1198 if (skb->len) 1199 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1200 1201 err_out: 1202 kfree_skb(skb); 1203 return -EINVAL; 1204 } 1205 1206 static bool tc_qdisc_dump_ignore(struct Qdisc *q) 1207 { 1208 return (q->flags & TCQ_F_BUILTIN) ? true : false; 1209 } 1210 1211 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1212 struct netlink_callback *cb, 1213 int *q_idx_p, int s_q_idx) 1214 { 1215 int ret = 0, q_idx = *q_idx_p; 1216 struct Qdisc *q; 1217 1218 if (!root) 1219 return 0; 1220 1221 q = root; 1222 if (q_idx < s_q_idx) { 1223 q_idx++; 1224 } else { 1225 if (!tc_qdisc_dump_ignore(q) && 1226 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1227 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1228 goto done; 1229 q_idx++; 1230 } 1231 list_for_each_entry(q, &root->list, list) { 1232 if (q_idx < s_q_idx) { 1233 q_idx++; 1234 continue; 1235 } 1236 if (!tc_qdisc_dump_ignore(q) && 1237 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1238 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1239 goto done; 1240 q_idx++; 1241 } 1242 1243 out: 1244 *q_idx_p = q_idx; 1245 return ret; 1246 done: 1247 ret = -1; 1248 goto out; 1249 } 1250 1251 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1252 { 1253 struct net *net = sock_net(skb->sk); 1254 int idx, q_idx; 1255 int s_idx, s_q_idx; 1256 struct net_device *dev; 1257 1258 if (net != &init_net) 1259 return 0; 1260 1261 s_idx = cb->args[0]; 1262 s_q_idx = q_idx = cb->args[1]; 1263 read_lock(&dev_base_lock); 1264 idx = 0; 1265 for_each_netdev(&init_net, dev) { 1266 struct netdev_queue *dev_queue; 1267 1268 if (idx < s_idx) 1269 goto cont; 1270 if (idx > s_idx) 1271 s_q_idx = 0; 1272 q_idx = 0; 1273 1274 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0) 1275 goto done; 1276 1277 dev_queue = &dev->rx_queue; 1278 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1279 goto done; 1280 1281 cont: 1282 idx++; 1283 } 1284 1285 done: 1286 read_unlock(&dev_base_lock); 1287 1288 cb->args[0] = idx; 1289 cb->args[1] = q_idx; 1290 1291 return skb->len; 1292 } 1293 1294 1295 1296 /************************************************ 1297 * Traffic classes manipulation. * 1298 ************************************************/ 1299 1300 1301 1302 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1303 { 1304 struct net *net = sock_net(skb->sk); 1305 struct tcmsg *tcm = NLMSG_DATA(n); 1306 struct nlattr *tca[TCA_MAX + 1]; 1307 struct net_device *dev; 1308 struct Qdisc *q = NULL; 1309 const struct Qdisc_class_ops *cops; 1310 unsigned long cl = 0; 1311 unsigned long new_cl; 1312 u32 pid = tcm->tcm_parent; 1313 u32 clid = tcm->tcm_handle; 1314 u32 qid = TC_H_MAJ(clid); 1315 int err; 1316 1317 if (net != &init_net) 1318 return -EINVAL; 1319 1320 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1321 return -ENODEV; 1322 1323 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1324 if (err < 0) 1325 return err; 1326 1327 /* 1328 parent == TC_H_UNSPEC - unspecified parent. 1329 parent == TC_H_ROOT - class is root, which has no parent. 1330 parent == X:0 - parent is root class. 1331 parent == X:Y - parent is a node in hierarchy. 1332 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 1333 1334 handle == 0:0 - generate handle from kernel pool. 1335 handle == 0:Y - class is X:Y, where X:0 is qdisc. 1336 handle == X:Y - clear. 1337 handle == X:0 - root class. 1338 */ 1339 1340 /* Step 1. Determine qdisc handle X:0 */ 1341 1342 if (pid != TC_H_ROOT) { 1343 u32 qid1 = TC_H_MAJ(pid); 1344 1345 if (qid && qid1) { 1346 /* If both majors are known, they must be identical. */ 1347 if (qid != qid1) 1348 return -EINVAL; 1349 } else if (qid1) { 1350 qid = qid1; 1351 } else if (qid == 0) 1352 qid = dev->qdisc->handle; 1353 1354 /* Now qid is genuine qdisc handle consistent 1355 both with parent and child. 1356 1357 TC_H_MAJ(pid) still may be unspecified, complete it now. 1358 */ 1359 if (pid) 1360 pid = TC_H_MAKE(qid, pid); 1361 } else { 1362 if (qid == 0) 1363 qid = dev->qdisc->handle; 1364 } 1365 1366 /* OK. Locate qdisc */ 1367 if ((q = qdisc_lookup(dev, qid)) == NULL) 1368 return -ENOENT; 1369 1370 /* An check that it supports classes */ 1371 cops = q->ops->cl_ops; 1372 if (cops == NULL) 1373 return -EINVAL; 1374 1375 /* Now try to get class */ 1376 if (clid == 0) { 1377 if (pid == TC_H_ROOT) 1378 clid = qid; 1379 } else 1380 clid = TC_H_MAKE(qid, clid); 1381 1382 if (clid) 1383 cl = cops->get(q, clid); 1384 1385 if (cl == 0) { 1386 err = -ENOENT; 1387 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE)) 1388 goto out; 1389 } else { 1390 switch (n->nlmsg_type) { 1391 case RTM_NEWTCLASS: 1392 err = -EEXIST; 1393 if (n->nlmsg_flags&NLM_F_EXCL) 1394 goto out; 1395 break; 1396 case RTM_DELTCLASS: 1397 err = -EOPNOTSUPP; 1398 if (cops->delete) 1399 err = cops->delete(q, cl); 1400 if (err == 0) 1401 tclass_notify(skb, n, q, cl, RTM_DELTCLASS); 1402 goto out; 1403 case RTM_GETTCLASS: 1404 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS); 1405 goto out; 1406 default: 1407 err = -EINVAL; 1408 goto out; 1409 } 1410 } 1411 1412 new_cl = cl; 1413 err = -EOPNOTSUPP; 1414 if (cops->change) 1415 err = cops->change(q, clid, pid, tca, &new_cl); 1416 if (err == 0) 1417 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS); 1418 1419 out: 1420 if (cl) 1421 cops->put(q, cl); 1422 1423 return err; 1424 } 1425 1426 1427 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1428 unsigned long cl, 1429 u32 pid, u32 seq, u16 flags, int event) 1430 { 1431 struct tcmsg *tcm; 1432 struct nlmsghdr *nlh; 1433 unsigned char *b = skb_tail_pointer(skb); 1434 struct gnet_dump d; 1435 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1436 1437 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1438 tcm = NLMSG_DATA(nlh); 1439 tcm->tcm_family = AF_UNSPEC; 1440 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1441 tcm->tcm_parent = q->handle; 1442 tcm->tcm_handle = q->handle; 1443 tcm->tcm_info = 0; 1444 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1445 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1446 goto nla_put_failure; 1447 1448 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1449 qdisc_root_sleeping_lock(q), &d) < 0) 1450 goto nla_put_failure; 1451 1452 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1453 goto nla_put_failure; 1454 1455 if (gnet_stats_finish_copy(&d) < 0) 1456 goto nla_put_failure; 1457 1458 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1459 return skb->len; 1460 1461 nlmsg_failure: 1462 nla_put_failure: 1463 nlmsg_trim(skb, b); 1464 return -1; 1465 } 1466 1467 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1468 struct Qdisc *q, unsigned long cl, int event) 1469 { 1470 struct sk_buff *skb; 1471 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1472 1473 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1474 if (!skb) 1475 return -ENOBUFS; 1476 1477 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) { 1478 kfree_skb(skb); 1479 return -EINVAL; 1480 } 1481 1482 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1483 } 1484 1485 struct qdisc_dump_args 1486 { 1487 struct qdisc_walker w; 1488 struct sk_buff *skb; 1489 struct netlink_callback *cb; 1490 }; 1491 1492 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg) 1493 { 1494 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 1495 1496 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid, 1497 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS); 1498 } 1499 1500 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 1501 struct tcmsg *tcm, struct netlink_callback *cb, 1502 int *t_p, int s_t) 1503 { 1504 struct qdisc_dump_args arg; 1505 1506 if (tc_qdisc_dump_ignore(q) || 1507 *t_p < s_t || !q->ops->cl_ops || 1508 (tcm->tcm_parent && 1509 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 1510 (*t_p)++; 1511 return 0; 1512 } 1513 if (*t_p > s_t) 1514 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 1515 arg.w.fn = qdisc_class_dump; 1516 arg.skb = skb; 1517 arg.cb = cb; 1518 arg.w.stop = 0; 1519 arg.w.skip = cb->args[1]; 1520 arg.w.count = 0; 1521 q->ops->cl_ops->walk(q, &arg.w); 1522 cb->args[1] = arg.w.count; 1523 if (arg.w.stop) 1524 return -1; 1525 (*t_p)++; 1526 return 0; 1527 } 1528 1529 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 1530 struct tcmsg *tcm, struct netlink_callback *cb, 1531 int *t_p, int s_t) 1532 { 1533 struct Qdisc *q; 1534 1535 if (!root) 1536 return 0; 1537 1538 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 1539 return -1; 1540 1541 list_for_each_entry(q, &root->list, list) { 1542 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 1543 return -1; 1544 } 1545 1546 return 0; 1547 } 1548 1549 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 1550 { 1551 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh); 1552 struct net *net = sock_net(skb->sk); 1553 struct netdev_queue *dev_queue; 1554 struct net_device *dev; 1555 int t, s_t; 1556 1557 if (net != &init_net) 1558 return 0; 1559 1560 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm))) 1561 return 0; 1562 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1563 return 0; 1564 1565 s_t = cb->args[0]; 1566 t = 0; 1567 1568 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0) 1569 goto done; 1570 1571 dev_queue = &dev->rx_queue; 1572 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1573 goto done; 1574 1575 done: 1576 cb->args[0] = t; 1577 1578 dev_put(dev); 1579 return skb->len; 1580 } 1581 1582 /* Main classifier routine: scans classifier chain attached 1583 to this qdisc, (optionally) tests for protocol and asks 1584 specific classifiers. 1585 */ 1586 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp, 1587 struct tcf_result *res) 1588 { 1589 __be16 protocol = skb->protocol; 1590 int err = 0; 1591 1592 for (; tp; tp = tp->next) { 1593 if ((tp->protocol == protocol || 1594 tp->protocol == htons(ETH_P_ALL)) && 1595 (err = tp->classify(skb, tp, res)) >= 0) { 1596 #ifdef CONFIG_NET_CLS_ACT 1597 if (err != TC_ACT_RECLASSIFY && skb->tc_verd) 1598 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0); 1599 #endif 1600 return err; 1601 } 1602 } 1603 return -1; 1604 } 1605 EXPORT_SYMBOL(tc_classify_compat); 1606 1607 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp, 1608 struct tcf_result *res) 1609 { 1610 int err = 0; 1611 __be16 protocol; 1612 #ifdef CONFIG_NET_CLS_ACT 1613 struct tcf_proto *otp = tp; 1614 reclassify: 1615 #endif 1616 protocol = skb->protocol; 1617 1618 err = tc_classify_compat(skb, tp, res); 1619 #ifdef CONFIG_NET_CLS_ACT 1620 if (err == TC_ACT_RECLASSIFY) { 1621 u32 verd = G_TC_VERD(skb->tc_verd); 1622 tp = otp; 1623 1624 if (verd++ >= MAX_REC_LOOP) { 1625 printk("rule prio %u protocol %02x reclassify loop, " 1626 "packet dropped\n", 1627 tp->prio&0xffff, ntohs(tp->protocol)); 1628 return TC_ACT_SHOT; 1629 } 1630 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd); 1631 goto reclassify; 1632 } 1633 #endif 1634 return err; 1635 } 1636 EXPORT_SYMBOL(tc_classify); 1637 1638 void tcf_destroy(struct tcf_proto *tp) 1639 { 1640 tp->ops->destroy(tp); 1641 module_put(tp->ops->owner); 1642 kfree(tp); 1643 } 1644 1645 void tcf_destroy_chain(struct tcf_proto **fl) 1646 { 1647 struct tcf_proto *tp; 1648 1649 while ((tp = *fl) != NULL) { 1650 *fl = tp->next; 1651 tcf_destroy(tp); 1652 } 1653 } 1654 EXPORT_SYMBOL(tcf_destroy_chain); 1655 1656 #ifdef CONFIG_PROC_FS 1657 static int psched_show(struct seq_file *seq, void *v) 1658 { 1659 struct timespec ts; 1660 1661 hrtimer_get_res(CLOCK_MONOTONIC, &ts); 1662 seq_printf(seq, "%08x %08x %08x %08x\n", 1663 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 1664 1000000, 1665 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts))); 1666 1667 return 0; 1668 } 1669 1670 static int psched_open(struct inode *inode, struct file *file) 1671 { 1672 return single_open(file, psched_show, PDE(inode)->data); 1673 } 1674 1675 static const struct file_operations psched_fops = { 1676 .owner = THIS_MODULE, 1677 .open = psched_open, 1678 .read = seq_read, 1679 .llseek = seq_lseek, 1680 .release = single_release, 1681 }; 1682 #endif 1683 1684 static int __init pktsched_init(void) 1685 { 1686 register_qdisc(&pfifo_qdisc_ops); 1687 register_qdisc(&bfifo_qdisc_ops); 1688 register_qdisc(&mq_qdisc_ops); 1689 proc_net_fops_create(&init_net, "psched", 0, &psched_fops); 1690 1691 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL); 1692 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL); 1693 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc); 1694 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL); 1695 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL); 1696 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass); 1697 1698 return 0; 1699 } 1700 1701 subsys_initcall(pktsched_init); 1702