1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * net/sched/sch_api.c Packet scheduler API. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 * 7 * Fixes: 8 * 9 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired. 10 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support 11 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support 12 */ 13 14 #include <linux/module.h> 15 #include <linux/types.h> 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <linux/errno.h> 19 #include <linux/skbuff.h> 20 #include <linux/init.h> 21 #include <linux/proc_fs.h> 22 #include <linux/seq_file.h> 23 #include <linux/kmod.h> 24 #include <linux/list.h> 25 #include <linux/hrtimer.h> 26 #include <linux/slab.h> 27 #include <linux/hashtable.h> 28 29 #include <net/net_namespace.h> 30 #include <net/sock.h> 31 #include <net/netlink.h> 32 #include <net/pkt_sched.h> 33 #include <net/pkt_cls.h> 34 35 #include <trace/events/qdisc.h> 36 37 /* 38 39 Short review. 40 ------------- 41 42 This file consists of two interrelated parts: 43 44 1. queueing disciplines manager frontend. 45 2. traffic classes manager frontend. 46 47 Generally, queueing discipline ("qdisc") is a black box, 48 which is able to enqueue packets and to dequeue them (when 49 device is ready to send something) in order and at times 50 determined by algorithm hidden in it. 51 52 qdisc's are divided to two categories: 53 - "queues", which have no internal structure visible from outside. 54 - "schedulers", which split all the packets to "traffic classes", 55 using "packet classifiers" (look at cls_api.c) 56 57 In turn, classes may have child qdiscs (as rule, queues) 58 attached to them etc. etc. etc. 59 60 The goal of the routines in this file is to translate 61 information supplied by user in the form of handles 62 to more intelligible for kernel form, to make some sanity 63 checks and part of work, which is common to all qdiscs 64 and to provide rtnetlink notifications. 65 66 All real intelligent work is done inside qdisc modules. 67 68 69 70 Every discipline has two major routines: enqueue and dequeue. 71 72 ---dequeue 73 74 dequeue usually returns a skb to send. It is allowed to return NULL, 75 but it does not mean that queue is empty, it just means that 76 discipline does not want to send anything this time. 77 Queue is really empty if q->q.qlen == 0. 78 For complicated disciplines with multiple queues q->q is not 79 real packet queue, but however q->q.qlen must be valid. 80 81 ---enqueue 82 83 enqueue returns 0, if packet was enqueued successfully. 84 If packet (this one or another one) was dropped, it returns 85 not zero error code. 86 NET_XMIT_DROP - this packet dropped 87 Expected action: do not backoff, but wait until queue will clear. 88 NET_XMIT_CN - probably this packet enqueued, but another one dropped. 89 Expected action: backoff or ignore 90 91 Auxiliary routines: 92 93 ---peek 94 95 like dequeue but without removing a packet from the queue 96 97 ---reset 98 99 returns qdisc to initial state: purge all buffers, clear all 100 timers, counters (except for statistics) etc. 101 102 ---init 103 104 initializes newly created qdisc. 105 106 ---destroy 107 108 destroys resources allocated by init and during lifetime of qdisc. 109 110 ---change 111 112 changes qdisc parameters. 113 */ 114 115 /* Protects list of registered TC modules. It is pure SMP lock. */ 116 static DEFINE_RWLOCK(qdisc_mod_lock); 117 118 119 /************************************************ 120 * Queueing disciplines manipulation. * 121 ************************************************/ 122 123 124 /* The list of all installed queueing disciplines. */ 125 126 static struct Qdisc_ops *qdisc_base; 127 128 /* Register/unregister queueing discipline */ 129 130 int register_qdisc(struct Qdisc_ops *qops) 131 { 132 struct Qdisc_ops *q, **qp; 133 int rc = -EEXIST; 134 135 write_lock(&qdisc_mod_lock); 136 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 137 if (!strcmp(qops->id, q->id)) 138 goto out; 139 140 if (qops->enqueue == NULL) 141 qops->enqueue = noop_qdisc_ops.enqueue; 142 if (qops->peek == NULL) { 143 if (qops->dequeue == NULL) 144 qops->peek = noop_qdisc_ops.peek; 145 else 146 goto out_einval; 147 } 148 if (qops->dequeue == NULL) 149 qops->dequeue = noop_qdisc_ops.dequeue; 150 151 if (qops->cl_ops) { 152 const struct Qdisc_class_ops *cops = qops->cl_ops; 153 154 if (!(cops->find && cops->walk && cops->leaf)) 155 goto out_einval; 156 157 if (cops->tcf_block && !(cops->bind_tcf && cops->unbind_tcf)) 158 goto out_einval; 159 } 160 161 qops->next = NULL; 162 *qp = qops; 163 rc = 0; 164 out: 165 write_unlock(&qdisc_mod_lock); 166 return rc; 167 168 out_einval: 169 rc = -EINVAL; 170 goto out; 171 } 172 EXPORT_SYMBOL(register_qdisc); 173 174 int unregister_qdisc(struct Qdisc_ops *qops) 175 { 176 struct Qdisc_ops *q, **qp; 177 int err = -ENOENT; 178 179 write_lock(&qdisc_mod_lock); 180 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 181 if (q == qops) 182 break; 183 if (q) { 184 *qp = q->next; 185 q->next = NULL; 186 err = 0; 187 } 188 write_unlock(&qdisc_mod_lock); 189 return err; 190 } 191 EXPORT_SYMBOL(unregister_qdisc); 192 193 /* Get default qdisc if not otherwise specified */ 194 void qdisc_get_default(char *name, size_t len) 195 { 196 read_lock(&qdisc_mod_lock); 197 strlcpy(name, default_qdisc_ops->id, len); 198 read_unlock(&qdisc_mod_lock); 199 } 200 201 static struct Qdisc_ops *qdisc_lookup_default(const char *name) 202 { 203 struct Qdisc_ops *q = NULL; 204 205 for (q = qdisc_base; q; q = q->next) { 206 if (!strcmp(name, q->id)) { 207 if (!try_module_get(q->owner)) 208 q = NULL; 209 break; 210 } 211 } 212 213 return q; 214 } 215 216 /* Set new default qdisc to use */ 217 int qdisc_set_default(const char *name) 218 { 219 const struct Qdisc_ops *ops; 220 221 if (!capable(CAP_NET_ADMIN)) 222 return -EPERM; 223 224 write_lock(&qdisc_mod_lock); 225 ops = qdisc_lookup_default(name); 226 if (!ops) { 227 /* Not found, drop lock and try to load module */ 228 write_unlock(&qdisc_mod_lock); 229 request_module("sch_%s", name); 230 write_lock(&qdisc_mod_lock); 231 232 ops = qdisc_lookup_default(name); 233 } 234 235 if (ops) { 236 /* Set new default */ 237 module_put(default_qdisc_ops->owner); 238 default_qdisc_ops = ops; 239 } 240 write_unlock(&qdisc_mod_lock); 241 242 return ops ? 0 : -ENOENT; 243 } 244 245 #ifdef CONFIG_NET_SCH_DEFAULT 246 /* Set default value from kernel config */ 247 static int __init sch_default_qdisc(void) 248 { 249 return qdisc_set_default(CONFIG_DEFAULT_NET_SCH); 250 } 251 late_initcall(sch_default_qdisc); 252 #endif 253 254 /* We know handle. Find qdisc among all qdisc's attached to device 255 * (root qdisc, all its children, children of children etc.) 256 * Note: caller either uses rtnl or rcu_read_lock() 257 */ 258 259 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 260 { 261 struct Qdisc *q; 262 263 if (!qdisc_dev(root)) 264 return (root->handle == handle ? root : NULL); 265 266 if (!(root->flags & TCQ_F_BUILTIN) && 267 root->handle == handle) 268 return root; 269 270 hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle) { 271 if (q->handle == handle) 272 return q; 273 } 274 return NULL; 275 } 276 277 void qdisc_hash_add(struct Qdisc *q, bool invisible) 278 { 279 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 280 ASSERT_RTNL(); 281 hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle); 282 if (invisible) 283 q->flags |= TCQ_F_INVISIBLE; 284 } 285 } 286 EXPORT_SYMBOL(qdisc_hash_add); 287 288 void qdisc_hash_del(struct Qdisc *q) 289 { 290 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 291 ASSERT_RTNL(); 292 hash_del_rcu(&q->hash); 293 } 294 } 295 EXPORT_SYMBOL(qdisc_hash_del); 296 297 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 298 { 299 struct Qdisc *q; 300 301 if (!handle) 302 return NULL; 303 q = qdisc_match_from_root(dev->qdisc, handle); 304 if (q) 305 goto out; 306 307 if (dev_ingress_queue(dev)) 308 q = qdisc_match_from_root( 309 dev_ingress_queue(dev)->qdisc_sleeping, 310 handle); 311 out: 312 return q; 313 } 314 315 struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle) 316 { 317 struct netdev_queue *nq; 318 struct Qdisc *q; 319 320 if (!handle) 321 return NULL; 322 q = qdisc_match_from_root(dev->qdisc, handle); 323 if (q) 324 goto out; 325 326 nq = dev_ingress_queue_rcu(dev); 327 if (nq) 328 q = qdisc_match_from_root(nq->qdisc_sleeping, handle); 329 out: 330 return q; 331 } 332 333 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 334 { 335 unsigned long cl; 336 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 337 338 if (cops == NULL) 339 return NULL; 340 cl = cops->find(p, classid); 341 342 if (cl == 0) 343 return NULL; 344 return cops->leaf(p, cl); 345 } 346 347 /* Find queueing discipline by name */ 348 349 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 350 { 351 struct Qdisc_ops *q = NULL; 352 353 if (kind) { 354 read_lock(&qdisc_mod_lock); 355 for (q = qdisc_base; q; q = q->next) { 356 if (nla_strcmp(kind, q->id) == 0) { 357 if (!try_module_get(q->owner)) 358 q = NULL; 359 break; 360 } 361 } 362 read_unlock(&qdisc_mod_lock); 363 } 364 return q; 365 } 366 367 /* The linklayer setting were not transferred from iproute2, in older 368 * versions, and the rate tables lookup systems have been dropped in 369 * the kernel. To keep backward compatible with older iproute2 tc 370 * utils, we detect the linklayer setting by detecting if the rate 371 * table were modified. 372 * 373 * For linklayer ATM table entries, the rate table will be aligned to 374 * 48 bytes, thus some table entries will contain the same value. The 375 * mpu (min packet unit) is also encoded into the old rate table, thus 376 * starting from the mpu, we find low and high table entries for 377 * mapping this cell. If these entries contain the same value, when 378 * the rate tables have been modified for linklayer ATM. 379 * 380 * This is done by rounding mpu to the nearest 48 bytes cell/entry, 381 * and then roundup to the next cell, calc the table entry one below, 382 * and compare. 383 */ 384 static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab) 385 { 386 int low = roundup(r->mpu, 48); 387 int high = roundup(low+1, 48); 388 int cell_low = low >> r->cell_log; 389 int cell_high = (high >> r->cell_log) - 1; 390 391 /* rtab is too inaccurate at rates > 100Mbit/s */ 392 if ((r->rate > (100000000/8)) || (rtab[0] == 0)) { 393 pr_debug("TC linklayer: Giving up ATM detection\n"); 394 return TC_LINKLAYER_ETHERNET; 395 } 396 397 if ((cell_high > cell_low) && (cell_high < 256) 398 && (rtab[cell_low] == rtab[cell_high])) { 399 pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n", 400 cell_low, cell_high, rtab[cell_high]); 401 return TC_LINKLAYER_ATM; 402 } 403 return TC_LINKLAYER_ETHERNET; 404 } 405 406 static struct qdisc_rate_table *qdisc_rtab_list; 407 408 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, 409 struct nlattr *tab, 410 struct netlink_ext_ack *extack) 411 { 412 struct qdisc_rate_table *rtab; 413 414 if (tab == NULL || r->rate == 0 || r->cell_log == 0 || 415 nla_len(tab) != TC_RTAB_SIZE) { 416 NL_SET_ERR_MSG(extack, "Invalid rate table parameters for searching"); 417 return NULL; 418 } 419 420 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 421 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) && 422 !memcmp(&rtab->data, nla_data(tab), 1024)) { 423 rtab->refcnt++; 424 return rtab; 425 } 426 } 427 428 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 429 if (rtab) { 430 rtab->rate = *r; 431 rtab->refcnt = 1; 432 memcpy(rtab->data, nla_data(tab), 1024); 433 if (r->linklayer == TC_LINKLAYER_UNAWARE) 434 r->linklayer = __detect_linklayer(r, rtab->data); 435 rtab->next = qdisc_rtab_list; 436 qdisc_rtab_list = rtab; 437 } else { 438 NL_SET_ERR_MSG(extack, "Failed to allocate new qdisc rate table"); 439 } 440 return rtab; 441 } 442 EXPORT_SYMBOL(qdisc_get_rtab); 443 444 void qdisc_put_rtab(struct qdisc_rate_table *tab) 445 { 446 struct qdisc_rate_table *rtab, **rtabp; 447 448 if (!tab || --tab->refcnt) 449 return; 450 451 for (rtabp = &qdisc_rtab_list; 452 (rtab = *rtabp) != NULL; 453 rtabp = &rtab->next) { 454 if (rtab == tab) { 455 *rtabp = rtab->next; 456 kfree(rtab); 457 return; 458 } 459 } 460 } 461 EXPORT_SYMBOL(qdisc_put_rtab); 462 463 static LIST_HEAD(qdisc_stab_list); 464 465 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 466 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 467 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 468 }; 469 470 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt, 471 struct netlink_ext_ack *extack) 472 { 473 struct nlattr *tb[TCA_STAB_MAX + 1]; 474 struct qdisc_size_table *stab; 475 struct tc_sizespec *s; 476 unsigned int tsize = 0; 477 u16 *tab = NULL; 478 int err; 479 480 err = nla_parse_nested_deprecated(tb, TCA_STAB_MAX, opt, stab_policy, 481 extack); 482 if (err < 0) 483 return ERR_PTR(err); 484 if (!tb[TCA_STAB_BASE]) { 485 NL_SET_ERR_MSG(extack, "Size table base attribute is missing"); 486 return ERR_PTR(-EINVAL); 487 } 488 489 s = nla_data(tb[TCA_STAB_BASE]); 490 491 if (s->tsize > 0) { 492 if (!tb[TCA_STAB_DATA]) { 493 NL_SET_ERR_MSG(extack, "Size table data attribute is missing"); 494 return ERR_PTR(-EINVAL); 495 } 496 tab = nla_data(tb[TCA_STAB_DATA]); 497 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 498 } 499 500 if (tsize != s->tsize || (!tab && tsize > 0)) { 501 NL_SET_ERR_MSG(extack, "Invalid size of size table"); 502 return ERR_PTR(-EINVAL); 503 } 504 505 list_for_each_entry(stab, &qdisc_stab_list, list) { 506 if (memcmp(&stab->szopts, s, sizeof(*s))) 507 continue; 508 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16))) 509 continue; 510 stab->refcnt++; 511 return stab; 512 } 513 514 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); 515 if (!stab) 516 return ERR_PTR(-ENOMEM); 517 518 stab->refcnt = 1; 519 stab->szopts = *s; 520 if (tsize > 0) 521 memcpy(stab->data, tab, tsize * sizeof(u16)); 522 523 list_add_tail(&stab->list, &qdisc_stab_list); 524 525 return stab; 526 } 527 528 void qdisc_put_stab(struct qdisc_size_table *tab) 529 { 530 if (!tab) 531 return; 532 533 if (--tab->refcnt == 0) { 534 list_del(&tab->list); 535 kfree_rcu(tab, rcu); 536 } 537 } 538 EXPORT_SYMBOL(qdisc_put_stab); 539 540 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 541 { 542 struct nlattr *nest; 543 544 nest = nla_nest_start_noflag(skb, TCA_STAB); 545 if (nest == NULL) 546 goto nla_put_failure; 547 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts)) 548 goto nla_put_failure; 549 nla_nest_end(skb, nest); 550 551 return skb->len; 552 553 nla_put_failure: 554 return -1; 555 } 556 557 void __qdisc_calculate_pkt_len(struct sk_buff *skb, 558 const struct qdisc_size_table *stab) 559 { 560 int pkt_len, slot; 561 562 pkt_len = skb->len + stab->szopts.overhead; 563 if (unlikely(!stab->szopts.tsize)) 564 goto out; 565 566 slot = pkt_len + stab->szopts.cell_align; 567 if (unlikely(slot < 0)) 568 slot = 0; 569 570 slot >>= stab->szopts.cell_log; 571 if (likely(slot < stab->szopts.tsize)) 572 pkt_len = stab->data[slot]; 573 else 574 pkt_len = stab->data[stab->szopts.tsize - 1] * 575 (slot / stab->szopts.tsize) + 576 stab->data[slot % stab->szopts.tsize]; 577 578 pkt_len <<= stab->szopts.size_log; 579 out: 580 if (unlikely(pkt_len < 1)) 581 pkt_len = 1; 582 qdisc_skb_cb(skb)->pkt_len = pkt_len; 583 } 584 EXPORT_SYMBOL(__qdisc_calculate_pkt_len); 585 586 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc) 587 { 588 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { 589 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n", 590 txt, qdisc->ops->id, qdisc->handle >> 16); 591 qdisc->flags |= TCQ_F_WARN_NONWC; 592 } 593 } 594 EXPORT_SYMBOL(qdisc_warn_nonwc); 595 596 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 597 { 598 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 599 timer); 600 601 rcu_read_lock(); 602 __netif_schedule(qdisc_root(wd->qdisc)); 603 rcu_read_unlock(); 604 605 return HRTIMER_NORESTART; 606 } 607 608 void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc, 609 clockid_t clockid) 610 { 611 hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED); 612 wd->timer.function = qdisc_watchdog; 613 wd->qdisc = qdisc; 614 } 615 EXPORT_SYMBOL(qdisc_watchdog_init_clockid); 616 617 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc) 618 { 619 qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC); 620 } 621 EXPORT_SYMBOL(qdisc_watchdog_init); 622 623 void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires, 624 u64 delta_ns) 625 { 626 if (test_bit(__QDISC_STATE_DEACTIVATED, 627 &qdisc_root_sleeping(wd->qdisc)->state)) 628 return; 629 630 if (hrtimer_is_queued(&wd->timer)) { 631 /* If timer is already set in [expires, expires + delta_ns], 632 * do not reprogram it. 633 */ 634 if (wd->last_expires - expires <= delta_ns) 635 return; 636 } 637 638 wd->last_expires = expires; 639 hrtimer_start_range_ns(&wd->timer, 640 ns_to_ktime(expires), 641 delta_ns, 642 HRTIMER_MODE_ABS_PINNED); 643 } 644 EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns); 645 646 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 647 { 648 hrtimer_cancel(&wd->timer); 649 } 650 EXPORT_SYMBOL(qdisc_watchdog_cancel); 651 652 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 653 { 654 struct hlist_head *h; 655 unsigned int i; 656 657 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL); 658 659 if (h != NULL) { 660 for (i = 0; i < n; i++) 661 INIT_HLIST_HEAD(&h[i]); 662 } 663 return h; 664 } 665 666 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 667 { 668 struct Qdisc_class_common *cl; 669 struct hlist_node *next; 670 struct hlist_head *nhash, *ohash; 671 unsigned int nsize, nmask, osize; 672 unsigned int i, h; 673 674 /* Rehash when load factor exceeds 0.75 */ 675 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 676 return; 677 nsize = clhash->hashsize * 2; 678 nmask = nsize - 1; 679 nhash = qdisc_class_hash_alloc(nsize); 680 if (nhash == NULL) 681 return; 682 683 ohash = clhash->hash; 684 osize = clhash->hashsize; 685 686 sch_tree_lock(sch); 687 for (i = 0; i < osize; i++) { 688 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) { 689 h = qdisc_class_hash(cl->classid, nmask); 690 hlist_add_head(&cl->hnode, &nhash[h]); 691 } 692 } 693 clhash->hash = nhash; 694 clhash->hashsize = nsize; 695 clhash->hashmask = nmask; 696 sch_tree_unlock(sch); 697 698 kvfree(ohash); 699 } 700 EXPORT_SYMBOL(qdisc_class_hash_grow); 701 702 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 703 { 704 unsigned int size = 4; 705 706 clhash->hash = qdisc_class_hash_alloc(size); 707 if (!clhash->hash) 708 return -ENOMEM; 709 clhash->hashsize = size; 710 clhash->hashmask = size - 1; 711 clhash->hashelems = 0; 712 return 0; 713 } 714 EXPORT_SYMBOL(qdisc_class_hash_init); 715 716 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 717 { 718 kvfree(clhash->hash); 719 } 720 EXPORT_SYMBOL(qdisc_class_hash_destroy); 721 722 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 723 struct Qdisc_class_common *cl) 724 { 725 unsigned int h; 726 727 INIT_HLIST_NODE(&cl->hnode); 728 h = qdisc_class_hash(cl->classid, clhash->hashmask); 729 hlist_add_head(&cl->hnode, &clhash->hash[h]); 730 clhash->hashelems++; 731 } 732 EXPORT_SYMBOL(qdisc_class_hash_insert); 733 734 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 735 struct Qdisc_class_common *cl) 736 { 737 hlist_del(&cl->hnode); 738 clhash->hashelems--; 739 } 740 EXPORT_SYMBOL(qdisc_class_hash_remove); 741 742 /* Allocate an unique handle from space managed by kernel 743 * Possible range is [8000-FFFF]:0000 (0x8000 values) 744 */ 745 static u32 qdisc_alloc_handle(struct net_device *dev) 746 { 747 int i = 0x8000; 748 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 749 750 do { 751 autohandle += TC_H_MAKE(0x10000U, 0); 752 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 753 autohandle = TC_H_MAKE(0x80000000U, 0); 754 if (!qdisc_lookup(dev, autohandle)) 755 return autohandle; 756 cond_resched(); 757 } while (--i > 0); 758 759 return 0; 760 } 761 762 void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len) 763 { 764 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED; 765 const struct Qdisc_class_ops *cops; 766 unsigned long cl; 767 u32 parentid; 768 bool notify; 769 int drops; 770 771 if (n == 0 && len == 0) 772 return; 773 drops = max_t(int, n, 0); 774 rcu_read_lock(); 775 while ((parentid = sch->parent)) { 776 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 777 break; 778 779 if (sch->flags & TCQ_F_NOPARENT) 780 break; 781 /* Notify parent qdisc only if child qdisc becomes empty. 782 * 783 * If child was empty even before update then backlog 784 * counter is screwed and we skip notification because 785 * parent class is already passive. 786 * 787 * If the original child was offloaded then it is allowed 788 * to be seem as empty, so the parent is notified anyway. 789 */ 790 notify = !sch->q.qlen && !WARN_ON_ONCE(!n && 791 !qdisc_is_offloaded); 792 /* TODO: perform the search on a per txq basis */ 793 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 794 if (sch == NULL) { 795 WARN_ON_ONCE(parentid != TC_H_ROOT); 796 break; 797 } 798 cops = sch->ops->cl_ops; 799 if (notify && cops->qlen_notify) { 800 cl = cops->find(sch, parentid); 801 cops->qlen_notify(sch, cl); 802 } 803 sch->q.qlen -= n; 804 sch->qstats.backlog -= len; 805 __qdisc_qstats_drop(sch, drops); 806 } 807 rcu_read_unlock(); 808 } 809 EXPORT_SYMBOL(qdisc_tree_reduce_backlog); 810 811 int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type, 812 void *type_data) 813 { 814 struct net_device *dev = qdisc_dev(sch); 815 int err; 816 817 sch->flags &= ~TCQ_F_OFFLOADED; 818 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 819 return 0; 820 821 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 822 if (err == -EOPNOTSUPP) 823 return 0; 824 825 if (!err) 826 sch->flags |= TCQ_F_OFFLOADED; 827 828 return err; 829 } 830 EXPORT_SYMBOL(qdisc_offload_dump_helper); 831 832 void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch, 833 struct Qdisc *new, struct Qdisc *old, 834 enum tc_setup_type type, void *type_data, 835 struct netlink_ext_ack *extack) 836 { 837 bool any_qdisc_is_offloaded; 838 int err; 839 840 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 841 return; 842 843 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 844 845 /* Don't report error if the graft is part of destroy operation. */ 846 if (!err || !new || new == &noop_qdisc) 847 return; 848 849 /* Don't report error if the parent, the old child and the new 850 * one are not offloaded. 851 */ 852 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED; 853 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED; 854 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED; 855 856 if (any_qdisc_is_offloaded) 857 NL_SET_ERR_MSG(extack, "Offloading graft operation failed."); 858 } 859 EXPORT_SYMBOL(qdisc_offload_graft_helper); 860 861 static void qdisc_offload_graft_root(struct net_device *dev, 862 struct Qdisc *new, struct Qdisc *old, 863 struct netlink_ext_ack *extack) 864 { 865 struct tc_root_qopt_offload graft_offload = { 866 .command = TC_ROOT_GRAFT, 867 .handle = new ? new->handle : 0, 868 .ingress = (new && new->flags & TCQ_F_INGRESS) || 869 (old && old->flags & TCQ_F_INGRESS), 870 }; 871 872 qdisc_offload_graft_helper(dev, NULL, new, old, 873 TC_SETUP_ROOT_QDISC, &graft_offload, extack); 874 } 875 876 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 877 u32 portid, u32 seq, u16 flags, int event) 878 { 879 struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL; 880 struct gnet_stats_queue __percpu *cpu_qstats = NULL; 881 struct tcmsg *tcm; 882 struct nlmsghdr *nlh; 883 unsigned char *b = skb_tail_pointer(skb); 884 struct gnet_dump d; 885 struct qdisc_size_table *stab; 886 u32 block_index; 887 __u32 qlen; 888 889 cond_resched(); 890 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 891 if (!nlh) 892 goto out_nlmsg_trim; 893 tcm = nlmsg_data(nlh); 894 tcm->tcm_family = AF_UNSPEC; 895 tcm->tcm__pad1 = 0; 896 tcm->tcm__pad2 = 0; 897 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 898 tcm->tcm_parent = clid; 899 tcm->tcm_handle = q->handle; 900 tcm->tcm_info = refcount_read(&q->refcnt); 901 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 902 goto nla_put_failure; 903 if (q->ops->ingress_block_get) { 904 block_index = q->ops->ingress_block_get(q); 905 if (block_index && 906 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index)) 907 goto nla_put_failure; 908 } 909 if (q->ops->egress_block_get) { 910 block_index = q->ops->egress_block_get(q); 911 if (block_index && 912 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index)) 913 goto nla_put_failure; 914 } 915 if (q->ops->dump && q->ops->dump(q, skb) < 0) 916 goto nla_put_failure; 917 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED))) 918 goto nla_put_failure; 919 qlen = qdisc_qlen_sum(q); 920 921 stab = rtnl_dereference(q->stab); 922 if (stab && qdisc_dump_stab(skb, stab) < 0) 923 goto nla_put_failure; 924 925 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 926 NULL, &d, TCA_PAD) < 0) 927 goto nla_put_failure; 928 929 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 930 goto nla_put_failure; 931 932 if (qdisc_is_percpu_stats(q)) { 933 cpu_bstats = q->cpu_bstats; 934 cpu_qstats = q->cpu_qstats; 935 } 936 937 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(q), 938 &d, cpu_bstats, &q->bstats) < 0 || 939 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 940 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0) 941 goto nla_put_failure; 942 943 if (gnet_stats_finish_copy(&d) < 0) 944 goto nla_put_failure; 945 946 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 947 return skb->len; 948 949 out_nlmsg_trim: 950 nla_put_failure: 951 nlmsg_trim(skb, b); 952 return -1; 953 } 954 955 static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible) 956 { 957 if (q->flags & TCQ_F_BUILTIN) 958 return true; 959 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible) 960 return true; 961 962 return false; 963 } 964 965 static int qdisc_notify(struct net *net, struct sk_buff *oskb, 966 struct nlmsghdr *n, u32 clid, 967 struct Qdisc *old, struct Qdisc *new) 968 { 969 struct sk_buff *skb; 970 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 971 972 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 973 if (!skb) 974 return -ENOBUFS; 975 976 if (old && !tc_qdisc_dump_ignore(old, false)) { 977 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq, 978 0, RTM_DELQDISC) < 0) 979 goto err_out; 980 } 981 if (new && !tc_qdisc_dump_ignore(new, false)) { 982 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq, 983 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 984 goto err_out; 985 } 986 987 if (skb->len) 988 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 989 n->nlmsg_flags & NLM_F_ECHO); 990 991 err_out: 992 kfree_skb(skb); 993 return -EINVAL; 994 } 995 996 static void notify_and_destroy(struct net *net, struct sk_buff *skb, 997 struct nlmsghdr *n, u32 clid, 998 struct Qdisc *old, struct Qdisc *new) 999 { 1000 if (new || old) 1001 qdisc_notify(net, skb, n, clid, old, new); 1002 1003 if (old) 1004 qdisc_put(old); 1005 } 1006 1007 static void qdisc_clear_nolock(struct Qdisc *sch) 1008 { 1009 sch->flags &= ~TCQ_F_NOLOCK; 1010 if (!(sch->flags & TCQ_F_CPUSTATS)) 1011 return; 1012 1013 free_percpu(sch->cpu_bstats); 1014 free_percpu(sch->cpu_qstats); 1015 sch->cpu_bstats = NULL; 1016 sch->cpu_qstats = NULL; 1017 sch->flags &= ~TCQ_F_CPUSTATS; 1018 } 1019 1020 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 1021 * to device "dev". 1022 * 1023 * When appropriate send a netlink notification using 'skb' 1024 * and "n". 1025 * 1026 * On success, destroy old qdisc. 1027 */ 1028 1029 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 1030 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 1031 struct Qdisc *new, struct Qdisc *old, 1032 struct netlink_ext_ack *extack) 1033 { 1034 struct Qdisc *q = old; 1035 struct net *net = dev_net(dev); 1036 1037 if (parent == NULL) { 1038 unsigned int i, num_q, ingress; 1039 1040 ingress = 0; 1041 num_q = dev->num_tx_queues; 1042 if ((q && q->flags & TCQ_F_INGRESS) || 1043 (new && new->flags & TCQ_F_INGRESS)) { 1044 num_q = 1; 1045 ingress = 1; 1046 if (!dev_ingress_queue(dev)) { 1047 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue"); 1048 return -ENOENT; 1049 } 1050 } 1051 1052 if (dev->flags & IFF_UP) 1053 dev_deactivate(dev); 1054 1055 qdisc_offload_graft_root(dev, new, old, extack); 1056 1057 if (new && new->ops->attach) 1058 goto skip; 1059 1060 for (i = 0; i < num_q; i++) { 1061 struct netdev_queue *dev_queue = dev_ingress_queue(dev); 1062 1063 if (!ingress) 1064 dev_queue = netdev_get_tx_queue(dev, i); 1065 1066 old = dev_graft_qdisc(dev_queue, new); 1067 if (new && i > 0) 1068 qdisc_refcount_inc(new); 1069 1070 if (!ingress) 1071 qdisc_put(old); 1072 } 1073 1074 skip: 1075 if (!ingress) { 1076 notify_and_destroy(net, skb, n, classid, 1077 dev->qdisc, new); 1078 if (new && !new->ops->attach) 1079 qdisc_refcount_inc(new); 1080 dev->qdisc = new ? : &noop_qdisc; 1081 1082 if (new && new->ops->attach) 1083 new->ops->attach(new); 1084 } else { 1085 notify_and_destroy(net, skb, n, classid, old, new); 1086 } 1087 1088 if (dev->flags & IFF_UP) 1089 dev_activate(dev); 1090 } else { 1091 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 1092 unsigned long cl; 1093 int err; 1094 1095 /* Only support running class lockless if parent is lockless */ 1096 if (new && (new->flags & TCQ_F_NOLOCK) && 1097 parent && !(parent->flags & TCQ_F_NOLOCK)) 1098 qdisc_clear_nolock(new); 1099 1100 if (!cops || !cops->graft) 1101 return -EOPNOTSUPP; 1102 1103 cl = cops->find(parent, classid); 1104 if (!cl) { 1105 NL_SET_ERR_MSG(extack, "Specified class not found"); 1106 return -ENOENT; 1107 } 1108 1109 err = cops->graft(parent, cl, new, &old, extack); 1110 if (err) 1111 return err; 1112 notify_and_destroy(net, skb, n, classid, old, new); 1113 } 1114 return 0; 1115 } 1116 1117 static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca, 1118 struct netlink_ext_ack *extack) 1119 { 1120 u32 block_index; 1121 1122 if (tca[TCA_INGRESS_BLOCK]) { 1123 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]); 1124 1125 if (!block_index) { 1126 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0"); 1127 return -EINVAL; 1128 } 1129 if (!sch->ops->ingress_block_set) { 1130 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported"); 1131 return -EOPNOTSUPP; 1132 } 1133 sch->ops->ingress_block_set(sch, block_index); 1134 } 1135 if (tca[TCA_EGRESS_BLOCK]) { 1136 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]); 1137 1138 if (!block_index) { 1139 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0"); 1140 return -EINVAL; 1141 } 1142 if (!sch->ops->egress_block_set) { 1143 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported"); 1144 return -EOPNOTSUPP; 1145 } 1146 sch->ops->egress_block_set(sch, block_index); 1147 } 1148 return 0; 1149 } 1150 1151 /* 1152 Allocate and initialize new qdisc. 1153 1154 Parameters are passed via opt. 1155 */ 1156 1157 static struct Qdisc *qdisc_create(struct net_device *dev, 1158 struct netdev_queue *dev_queue, 1159 struct Qdisc *p, u32 parent, u32 handle, 1160 struct nlattr **tca, int *errp, 1161 struct netlink_ext_ack *extack) 1162 { 1163 int err; 1164 struct nlattr *kind = tca[TCA_KIND]; 1165 struct Qdisc *sch; 1166 struct Qdisc_ops *ops; 1167 struct qdisc_size_table *stab; 1168 1169 ops = qdisc_lookup_ops(kind); 1170 #ifdef CONFIG_MODULES 1171 if (ops == NULL && kind != NULL) { 1172 char name[IFNAMSIZ]; 1173 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) { 1174 /* We dropped the RTNL semaphore in order to 1175 * perform the module load. So, even if we 1176 * succeeded in loading the module we have to 1177 * tell the caller to replay the request. We 1178 * indicate this using -EAGAIN. 1179 * We replay the request because the device may 1180 * go away in the mean time. 1181 */ 1182 rtnl_unlock(); 1183 request_module("sch_%s", name); 1184 rtnl_lock(); 1185 ops = qdisc_lookup_ops(kind); 1186 if (ops != NULL) { 1187 /* We will try again qdisc_lookup_ops, 1188 * so don't keep a reference. 1189 */ 1190 module_put(ops->owner); 1191 err = -EAGAIN; 1192 goto err_out; 1193 } 1194 } 1195 } 1196 #endif 1197 1198 err = -ENOENT; 1199 if (!ops) { 1200 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1201 goto err_out; 1202 } 1203 1204 sch = qdisc_alloc(dev_queue, ops, extack); 1205 if (IS_ERR(sch)) { 1206 err = PTR_ERR(sch); 1207 goto err_out2; 1208 } 1209 1210 sch->parent = parent; 1211 1212 if (handle == TC_H_INGRESS) { 1213 sch->flags |= TCQ_F_INGRESS; 1214 handle = TC_H_MAKE(TC_H_INGRESS, 0); 1215 } else { 1216 if (handle == 0) { 1217 handle = qdisc_alloc_handle(dev); 1218 if (handle == 0) { 1219 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded"); 1220 err = -ENOSPC; 1221 goto err_out3; 1222 } 1223 } 1224 if (!netif_is_multiqueue(dev)) 1225 sch->flags |= TCQ_F_ONETXQUEUE; 1226 } 1227 1228 sch->handle = handle; 1229 1230 /* This exist to keep backward compatible with a userspace 1231 * loophole, what allowed userspace to get IFF_NO_QUEUE 1232 * facility on older kernels by setting tx_queue_len=0 (prior 1233 * to qdisc init), and then forgot to reinit tx_queue_len 1234 * before again attaching a qdisc. 1235 */ 1236 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) { 1237 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 1238 netdev_info(dev, "Caught tx_queue_len zero misconfig\n"); 1239 } 1240 1241 err = qdisc_block_indexes_set(sch, tca, extack); 1242 if (err) 1243 goto err_out3; 1244 1245 if (ops->init) { 1246 err = ops->init(sch, tca[TCA_OPTIONS], extack); 1247 if (err != 0) 1248 goto err_out5; 1249 } 1250 1251 if (tca[TCA_STAB]) { 1252 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1253 if (IS_ERR(stab)) { 1254 err = PTR_ERR(stab); 1255 goto err_out4; 1256 } 1257 rcu_assign_pointer(sch->stab, stab); 1258 } 1259 if (tca[TCA_RATE]) { 1260 seqcount_t *running; 1261 1262 err = -EOPNOTSUPP; 1263 if (sch->flags & TCQ_F_MQROOT) { 1264 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc"); 1265 goto err_out4; 1266 } 1267 1268 if (sch->parent != TC_H_ROOT && 1269 !(sch->flags & TCQ_F_INGRESS) && 1270 (!p || !(p->flags & TCQ_F_MQROOT))) 1271 running = qdisc_root_sleeping_running(sch); 1272 else 1273 running = &sch->running; 1274 1275 err = gen_new_estimator(&sch->bstats, 1276 sch->cpu_bstats, 1277 &sch->rate_est, 1278 NULL, 1279 running, 1280 tca[TCA_RATE]); 1281 if (err) { 1282 NL_SET_ERR_MSG(extack, "Failed to generate new estimator"); 1283 goto err_out4; 1284 } 1285 } 1286 1287 qdisc_hash_add(sch, false); 1288 trace_qdisc_create(ops, dev, parent); 1289 1290 return sch; 1291 1292 err_out5: 1293 /* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */ 1294 if (ops->destroy) 1295 ops->destroy(sch); 1296 err_out3: 1297 dev_put(dev); 1298 qdisc_free(sch); 1299 err_out2: 1300 module_put(ops->owner); 1301 err_out: 1302 *errp = err; 1303 return NULL; 1304 1305 err_out4: 1306 /* 1307 * Any broken qdiscs that would require a ops->reset() here? 1308 * The qdisc was never in action so it shouldn't be necessary. 1309 */ 1310 qdisc_put_stab(rtnl_dereference(sch->stab)); 1311 if (ops->destroy) 1312 ops->destroy(sch); 1313 goto err_out3; 1314 } 1315 1316 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca, 1317 struct netlink_ext_ack *extack) 1318 { 1319 struct qdisc_size_table *ostab, *stab = NULL; 1320 int err = 0; 1321 1322 if (tca[TCA_OPTIONS]) { 1323 if (!sch->ops->change) { 1324 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc"); 1325 return -EINVAL; 1326 } 1327 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 1328 NL_SET_ERR_MSG(extack, "Change of blocks is not supported"); 1329 return -EOPNOTSUPP; 1330 } 1331 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack); 1332 if (err) 1333 return err; 1334 } 1335 1336 if (tca[TCA_STAB]) { 1337 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1338 if (IS_ERR(stab)) 1339 return PTR_ERR(stab); 1340 } 1341 1342 ostab = rtnl_dereference(sch->stab); 1343 rcu_assign_pointer(sch->stab, stab); 1344 qdisc_put_stab(ostab); 1345 1346 if (tca[TCA_RATE]) { 1347 /* NB: ignores errors from replace_estimator 1348 because change can't be undone. */ 1349 if (sch->flags & TCQ_F_MQROOT) 1350 goto out; 1351 gen_replace_estimator(&sch->bstats, 1352 sch->cpu_bstats, 1353 &sch->rate_est, 1354 NULL, 1355 qdisc_root_sleeping_running(sch), 1356 tca[TCA_RATE]); 1357 } 1358 out: 1359 return 0; 1360 } 1361 1362 struct check_loop_arg { 1363 struct qdisc_walker w; 1364 struct Qdisc *p; 1365 int depth; 1366 }; 1367 1368 static int check_loop_fn(struct Qdisc *q, unsigned long cl, 1369 struct qdisc_walker *w); 1370 1371 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 1372 { 1373 struct check_loop_arg arg; 1374 1375 if (q->ops->cl_ops == NULL) 1376 return 0; 1377 1378 arg.w.stop = arg.w.skip = arg.w.count = 0; 1379 arg.w.fn = check_loop_fn; 1380 arg.depth = depth; 1381 arg.p = p; 1382 q->ops->cl_ops->walk(q, &arg.w); 1383 return arg.w.stop ? -ELOOP : 0; 1384 } 1385 1386 static int 1387 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 1388 { 1389 struct Qdisc *leaf; 1390 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1391 struct check_loop_arg *arg = (struct check_loop_arg *)w; 1392 1393 leaf = cops->leaf(q, cl); 1394 if (leaf) { 1395 if (leaf == arg->p || arg->depth > 7) 1396 return -ELOOP; 1397 return check_loop(leaf, arg->p, arg->depth + 1); 1398 } 1399 return 0; 1400 } 1401 1402 const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = { 1403 [TCA_KIND] = { .type = NLA_STRING }, 1404 [TCA_RATE] = { .type = NLA_BINARY, 1405 .len = sizeof(struct tc_estimator) }, 1406 [TCA_STAB] = { .type = NLA_NESTED }, 1407 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG }, 1408 [TCA_CHAIN] = { .type = NLA_U32 }, 1409 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 }, 1410 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 }, 1411 }; 1412 1413 /* 1414 * Delete/get qdisc. 1415 */ 1416 1417 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1418 struct netlink_ext_ack *extack) 1419 { 1420 struct net *net = sock_net(skb->sk); 1421 struct tcmsg *tcm = nlmsg_data(n); 1422 struct nlattr *tca[TCA_MAX + 1]; 1423 struct net_device *dev; 1424 u32 clid; 1425 struct Qdisc *q = NULL; 1426 struct Qdisc *p = NULL; 1427 int err; 1428 1429 if ((n->nlmsg_type != RTM_GETQDISC) && 1430 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 1431 return -EPERM; 1432 1433 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1434 rtm_tca_policy, extack); 1435 if (err < 0) 1436 return err; 1437 1438 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1439 if (!dev) 1440 return -ENODEV; 1441 1442 clid = tcm->tcm_parent; 1443 if (clid) { 1444 if (clid != TC_H_ROOT) { 1445 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1446 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1447 if (!p) { 1448 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid"); 1449 return -ENOENT; 1450 } 1451 q = qdisc_leaf(p, clid); 1452 } else if (dev_ingress_queue(dev)) { 1453 q = dev_ingress_queue(dev)->qdisc_sleeping; 1454 } 1455 } else { 1456 q = dev->qdisc; 1457 } 1458 if (!q) { 1459 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); 1460 return -ENOENT; 1461 } 1462 1463 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) { 1464 NL_SET_ERR_MSG(extack, "Invalid handle"); 1465 return -EINVAL; 1466 } 1467 } else { 1468 q = qdisc_lookup(dev, tcm->tcm_handle); 1469 if (!q) { 1470 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle"); 1471 return -ENOENT; 1472 } 1473 } 1474 1475 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1476 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1477 return -EINVAL; 1478 } 1479 1480 if (n->nlmsg_type == RTM_DELQDISC) { 1481 if (!clid) { 1482 NL_SET_ERR_MSG(extack, "Classid cannot be zero"); 1483 return -EINVAL; 1484 } 1485 if (q->handle == 0) { 1486 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero"); 1487 return -ENOENT; 1488 } 1489 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack); 1490 if (err != 0) 1491 return err; 1492 } else { 1493 qdisc_notify(net, skb, n, clid, NULL, q); 1494 } 1495 return 0; 1496 } 1497 1498 /* 1499 * Create/change qdisc. 1500 */ 1501 1502 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1503 struct netlink_ext_ack *extack) 1504 { 1505 struct net *net = sock_net(skb->sk); 1506 struct tcmsg *tcm; 1507 struct nlattr *tca[TCA_MAX + 1]; 1508 struct net_device *dev; 1509 u32 clid; 1510 struct Qdisc *q, *p; 1511 int err; 1512 1513 if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 1514 return -EPERM; 1515 1516 replay: 1517 /* Reinit, just in case something touches this. */ 1518 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1519 rtm_tca_policy, extack); 1520 if (err < 0) 1521 return err; 1522 1523 tcm = nlmsg_data(n); 1524 clid = tcm->tcm_parent; 1525 q = p = NULL; 1526 1527 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1528 if (!dev) 1529 return -ENODEV; 1530 1531 1532 if (clid) { 1533 if (clid != TC_H_ROOT) { 1534 if (clid != TC_H_INGRESS) { 1535 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1536 if (!p) { 1537 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); 1538 return -ENOENT; 1539 } 1540 q = qdisc_leaf(p, clid); 1541 } else if (dev_ingress_queue_create(dev)) { 1542 q = dev_ingress_queue(dev)->qdisc_sleeping; 1543 } 1544 } else { 1545 q = dev->qdisc; 1546 } 1547 1548 /* It may be default qdisc, ignore it */ 1549 if (q && q->handle == 0) 1550 q = NULL; 1551 1552 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1553 if (tcm->tcm_handle) { 1554 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) { 1555 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override"); 1556 return -EEXIST; 1557 } 1558 if (TC_H_MIN(tcm->tcm_handle)) { 1559 NL_SET_ERR_MSG(extack, "Invalid minor handle"); 1560 return -EINVAL; 1561 } 1562 q = qdisc_lookup(dev, tcm->tcm_handle); 1563 if (!q) 1564 goto create_n_graft; 1565 if (n->nlmsg_flags & NLM_F_EXCL) { 1566 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override"); 1567 return -EEXIST; 1568 } 1569 if (tca[TCA_KIND] && 1570 nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1571 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1572 return -EINVAL; 1573 } 1574 if (q == p || 1575 (p && check_loop(q, p, 0))) { 1576 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected"); 1577 return -ELOOP; 1578 } 1579 qdisc_refcount_inc(q); 1580 goto graft; 1581 } else { 1582 if (!q) 1583 goto create_n_graft; 1584 1585 /* This magic test requires explanation. 1586 * 1587 * We know, that some child q is already 1588 * attached to this parent and have choice: 1589 * either to change it or to create/graft new one. 1590 * 1591 * 1. We are allowed to create/graft only 1592 * if CREATE and REPLACE flags are set. 1593 * 1594 * 2. If EXCL is set, requestor wanted to say, 1595 * that qdisc tcm_handle is not expected 1596 * to exist, so that we choose create/graft too. 1597 * 1598 * 3. The last case is when no flags are set. 1599 * Alas, it is sort of hole in API, we 1600 * cannot decide what to do unambiguously. 1601 * For now we select create/graft, if 1602 * user gave KIND, which does not match existing. 1603 */ 1604 if ((n->nlmsg_flags & NLM_F_CREATE) && 1605 (n->nlmsg_flags & NLM_F_REPLACE) && 1606 ((n->nlmsg_flags & NLM_F_EXCL) || 1607 (tca[TCA_KIND] && 1608 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1609 goto create_n_graft; 1610 } 1611 } 1612 } else { 1613 if (!tcm->tcm_handle) { 1614 NL_SET_ERR_MSG(extack, "Handle cannot be zero"); 1615 return -EINVAL; 1616 } 1617 q = qdisc_lookup(dev, tcm->tcm_handle); 1618 } 1619 1620 /* Change qdisc parameters */ 1621 if (!q) { 1622 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1623 return -ENOENT; 1624 } 1625 if (n->nlmsg_flags & NLM_F_EXCL) { 1626 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify"); 1627 return -EEXIST; 1628 } 1629 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1630 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1631 return -EINVAL; 1632 } 1633 err = qdisc_change(q, tca, extack); 1634 if (err == 0) 1635 qdisc_notify(net, skb, n, clid, NULL, q); 1636 return err; 1637 1638 create_n_graft: 1639 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 1640 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag"); 1641 return -ENOENT; 1642 } 1643 if (clid == TC_H_INGRESS) { 1644 if (dev_ingress_queue(dev)) { 1645 q = qdisc_create(dev, dev_ingress_queue(dev), p, 1646 tcm->tcm_parent, tcm->tcm_parent, 1647 tca, &err, extack); 1648 } else { 1649 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device"); 1650 err = -ENOENT; 1651 } 1652 } else { 1653 struct netdev_queue *dev_queue; 1654 1655 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1656 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1657 else if (p) 1658 dev_queue = p->dev_queue; 1659 else 1660 dev_queue = netdev_get_tx_queue(dev, 0); 1661 1662 q = qdisc_create(dev, dev_queue, p, 1663 tcm->tcm_parent, tcm->tcm_handle, 1664 tca, &err, extack); 1665 } 1666 if (q == NULL) { 1667 if (err == -EAGAIN) 1668 goto replay; 1669 return err; 1670 } 1671 1672 graft: 1673 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack); 1674 if (err) { 1675 if (q) 1676 qdisc_put(q); 1677 return err; 1678 } 1679 1680 return 0; 1681 } 1682 1683 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1684 struct netlink_callback *cb, 1685 int *q_idx_p, int s_q_idx, bool recur, 1686 bool dump_invisible) 1687 { 1688 int ret = 0, q_idx = *q_idx_p; 1689 struct Qdisc *q; 1690 int b; 1691 1692 if (!root) 1693 return 0; 1694 1695 q = root; 1696 if (q_idx < s_q_idx) { 1697 q_idx++; 1698 } else { 1699 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1700 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1701 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1702 RTM_NEWQDISC) <= 0) 1703 goto done; 1704 q_idx++; 1705 } 1706 1707 /* If dumping singletons, there is no qdisc_dev(root) and the singleton 1708 * itself has already been dumped. 1709 * 1710 * If we've already dumped the top-level (ingress) qdisc above and the global 1711 * qdisc hashtable, we don't want to hit it again 1712 */ 1713 if (!qdisc_dev(root) || !recur) 1714 goto out; 1715 1716 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 1717 if (q_idx < s_q_idx) { 1718 q_idx++; 1719 continue; 1720 } 1721 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1722 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1723 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1724 RTM_NEWQDISC) <= 0) 1725 goto done; 1726 q_idx++; 1727 } 1728 1729 out: 1730 *q_idx_p = q_idx; 1731 return ret; 1732 done: 1733 ret = -1; 1734 goto out; 1735 } 1736 1737 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1738 { 1739 struct net *net = sock_net(skb->sk); 1740 int idx, q_idx; 1741 int s_idx, s_q_idx; 1742 struct net_device *dev; 1743 const struct nlmsghdr *nlh = cb->nlh; 1744 struct nlattr *tca[TCA_MAX + 1]; 1745 int err; 1746 1747 s_idx = cb->args[0]; 1748 s_q_idx = q_idx = cb->args[1]; 1749 1750 idx = 0; 1751 ASSERT_RTNL(); 1752 1753 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX, 1754 rtm_tca_policy, cb->extack); 1755 if (err < 0) 1756 return err; 1757 1758 for_each_netdev(net, dev) { 1759 struct netdev_queue *dev_queue; 1760 1761 if (idx < s_idx) 1762 goto cont; 1763 if (idx > s_idx) 1764 s_q_idx = 0; 1765 q_idx = 0; 1766 1767 if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx, 1768 true, tca[TCA_DUMP_INVISIBLE]) < 0) 1769 goto done; 1770 1771 dev_queue = dev_ingress_queue(dev); 1772 if (dev_queue && 1773 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1774 &q_idx, s_q_idx, false, 1775 tca[TCA_DUMP_INVISIBLE]) < 0) 1776 goto done; 1777 1778 cont: 1779 idx++; 1780 } 1781 1782 done: 1783 cb->args[0] = idx; 1784 cb->args[1] = q_idx; 1785 1786 return skb->len; 1787 } 1788 1789 1790 1791 /************************************************ 1792 * Traffic classes manipulation. * 1793 ************************************************/ 1794 1795 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1796 unsigned long cl, 1797 u32 portid, u32 seq, u16 flags, int event) 1798 { 1799 struct tcmsg *tcm; 1800 struct nlmsghdr *nlh; 1801 unsigned char *b = skb_tail_pointer(skb); 1802 struct gnet_dump d; 1803 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1804 1805 cond_resched(); 1806 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1807 if (!nlh) 1808 goto out_nlmsg_trim; 1809 tcm = nlmsg_data(nlh); 1810 tcm->tcm_family = AF_UNSPEC; 1811 tcm->tcm__pad1 = 0; 1812 tcm->tcm__pad2 = 0; 1813 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1814 tcm->tcm_parent = q->handle; 1815 tcm->tcm_handle = q->handle; 1816 tcm->tcm_info = 0; 1817 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1818 goto nla_put_failure; 1819 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1820 goto nla_put_failure; 1821 1822 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1823 NULL, &d, TCA_PAD) < 0) 1824 goto nla_put_failure; 1825 1826 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1827 goto nla_put_failure; 1828 1829 if (gnet_stats_finish_copy(&d) < 0) 1830 goto nla_put_failure; 1831 1832 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1833 return skb->len; 1834 1835 out_nlmsg_trim: 1836 nla_put_failure: 1837 nlmsg_trim(skb, b); 1838 return -1; 1839 } 1840 1841 static int tclass_notify(struct net *net, struct sk_buff *oskb, 1842 struct nlmsghdr *n, struct Qdisc *q, 1843 unsigned long cl, int event) 1844 { 1845 struct sk_buff *skb; 1846 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1847 int err = 0; 1848 1849 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1850 if (!skb) 1851 return -ENOBUFS; 1852 1853 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) { 1854 kfree_skb(skb); 1855 return -EINVAL; 1856 } 1857 1858 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1859 n->nlmsg_flags & NLM_F_ECHO); 1860 if (err > 0) 1861 err = 0; 1862 return err; 1863 } 1864 1865 static int tclass_del_notify(struct net *net, 1866 const struct Qdisc_class_ops *cops, 1867 struct sk_buff *oskb, struct nlmsghdr *n, 1868 struct Qdisc *q, unsigned long cl) 1869 { 1870 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1871 struct sk_buff *skb; 1872 int err = 0; 1873 1874 if (!cops->delete) 1875 return -EOPNOTSUPP; 1876 1877 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1878 if (!skb) 1879 return -ENOBUFS; 1880 1881 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, 1882 RTM_DELTCLASS) < 0) { 1883 kfree_skb(skb); 1884 return -EINVAL; 1885 } 1886 1887 err = cops->delete(q, cl); 1888 if (err) { 1889 kfree_skb(skb); 1890 return err; 1891 } 1892 1893 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1894 n->nlmsg_flags & NLM_F_ECHO); 1895 if (err > 0) 1896 err = 0; 1897 return err; 1898 } 1899 1900 #ifdef CONFIG_NET_CLS 1901 1902 struct tcf_bind_args { 1903 struct tcf_walker w; 1904 unsigned long base; 1905 unsigned long cl; 1906 u32 classid; 1907 }; 1908 1909 static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 1910 { 1911 struct tcf_bind_args *a = (void *)arg; 1912 1913 if (tp->ops->bind_class) { 1914 struct Qdisc *q = tcf_block_q(tp->chain->block); 1915 1916 sch_tree_lock(q); 1917 tp->ops->bind_class(n, a->classid, a->cl, q, a->base); 1918 sch_tree_unlock(q); 1919 } 1920 return 0; 1921 } 1922 1923 struct tc_bind_class_args { 1924 struct qdisc_walker w; 1925 unsigned long new_cl; 1926 u32 portid; 1927 u32 clid; 1928 }; 1929 1930 static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl, 1931 struct qdisc_walker *w) 1932 { 1933 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w; 1934 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1935 struct tcf_block *block; 1936 struct tcf_chain *chain; 1937 1938 block = cops->tcf_block(q, cl, NULL); 1939 if (!block) 1940 return 0; 1941 for (chain = tcf_get_next_chain(block, NULL); 1942 chain; 1943 chain = tcf_get_next_chain(block, chain)) { 1944 struct tcf_proto *tp; 1945 1946 for (tp = tcf_get_next_proto(chain, NULL, true); 1947 tp; tp = tcf_get_next_proto(chain, tp, true)) { 1948 struct tcf_bind_args arg = {}; 1949 1950 arg.w.fn = tcf_node_bind; 1951 arg.classid = a->clid; 1952 arg.base = cl; 1953 arg.cl = a->new_cl; 1954 tp->ops->walk(tp, &arg.w, true); 1955 } 1956 } 1957 1958 return 0; 1959 } 1960 1961 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1962 unsigned long new_cl) 1963 { 1964 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1965 struct tc_bind_class_args args = {}; 1966 1967 if (!cops->tcf_block) 1968 return; 1969 args.portid = portid; 1970 args.clid = clid; 1971 args.new_cl = new_cl; 1972 args.w.fn = tc_bind_class_walker; 1973 q->ops->cl_ops->walk(q, &args.w); 1974 } 1975 1976 #else 1977 1978 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1979 unsigned long new_cl) 1980 { 1981 } 1982 1983 #endif 1984 1985 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 1986 struct netlink_ext_ack *extack) 1987 { 1988 struct net *net = sock_net(skb->sk); 1989 struct tcmsg *tcm = nlmsg_data(n); 1990 struct nlattr *tca[TCA_MAX + 1]; 1991 struct net_device *dev; 1992 struct Qdisc *q = NULL; 1993 const struct Qdisc_class_ops *cops; 1994 unsigned long cl = 0; 1995 unsigned long new_cl; 1996 u32 portid; 1997 u32 clid; 1998 u32 qid; 1999 int err; 2000 2001 if ((n->nlmsg_type != RTM_GETTCLASS) && 2002 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) 2003 return -EPERM; 2004 2005 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 2006 rtm_tca_policy, extack); 2007 if (err < 0) 2008 return err; 2009 2010 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2011 if (!dev) 2012 return -ENODEV; 2013 2014 /* 2015 parent == TC_H_UNSPEC - unspecified parent. 2016 parent == TC_H_ROOT - class is root, which has no parent. 2017 parent == X:0 - parent is root class. 2018 parent == X:Y - parent is a node in hierarchy. 2019 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 2020 2021 handle == 0:0 - generate handle from kernel pool. 2022 handle == 0:Y - class is X:Y, where X:0 is qdisc. 2023 handle == X:Y - clear. 2024 handle == X:0 - root class. 2025 */ 2026 2027 /* Step 1. Determine qdisc handle X:0 */ 2028 2029 portid = tcm->tcm_parent; 2030 clid = tcm->tcm_handle; 2031 qid = TC_H_MAJ(clid); 2032 2033 if (portid != TC_H_ROOT) { 2034 u32 qid1 = TC_H_MAJ(portid); 2035 2036 if (qid && qid1) { 2037 /* If both majors are known, they must be identical. */ 2038 if (qid != qid1) 2039 return -EINVAL; 2040 } else if (qid1) { 2041 qid = qid1; 2042 } else if (qid == 0) 2043 qid = dev->qdisc->handle; 2044 2045 /* Now qid is genuine qdisc handle consistent 2046 * both with parent and child. 2047 * 2048 * TC_H_MAJ(portid) still may be unspecified, complete it now. 2049 */ 2050 if (portid) 2051 portid = TC_H_MAKE(qid, portid); 2052 } else { 2053 if (qid == 0) 2054 qid = dev->qdisc->handle; 2055 } 2056 2057 /* OK. Locate qdisc */ 2058 q = qdisc_lookup(dev, qid); 2059 if (!q) 2060 return -ENOENT; 2061 2062 /* An check that it supports classes */ 2063 cops = q->ops->cl_ops; 2064 if (cops == NULL) 2065 return -EINVAL; 2066 2067 /* Now try to get class */ 2068 if (clid == 0) { 2069 if (portid == TC_H_ROOT) 2070 clid = qid; 2071 } else 2072 clid = TC_H_MAKE(qid, clid); 2073 2074 if (clid) 2075 cl = cops->find(q, clid); 2076 2077 if (cl == 0) { 2078 err = -ENOENT; 2079 if (n->nlmsg_type != RTM_NEWTCLASS || 2080 !(n->nlmsg_flags & NLM_F_CREATE)) 2081 goto out; 2082 } else { 2083 switch (n->nlmsg_type) { 2084 case RTM_NEWTCLASS: 2085 err = -EEXIST; 2086 if (n->nlmsg_flags & NLM_F_EXCL) 2087 goto out; 2088 break; 2089 case RTM_DELTCLASS: 2090 err = tclass_del_notify(net, cops, skb, n, q, cl); 2091 /* Unbind the class with flilters with 0 */ 2092 tc_bind_tclass(q, portid, clid, 0); 2093 goto out; 2094 case RTM_GETTCLASS: 2095 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS); 2096 goto out; 2097 default: 2098 err = -EINVAL; 2099 goto out; 2100 } 2101 } 2102 2103 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 2104 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes"); 2105 return -EOPNOTSUPP; 2106 } 2107 2108 new_cl = cl; 2109 err = -EOPNOTSUPP; 2110 if (cops->change) 2111 err = cops->change(q, clid, portid, tca, &new_cl, extack); 2112 if (err == 0) { 2113 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS); 2114 /* We just create a new class, need to do reverse binding. */ 2115 if (cl != new_cl) 2116 tc_bind_tclass(q, portid, clid, new_cl); 2117 } 2118 out: 2119 return err; 2120 } 2121 2122 struct qdisc_dump_args { 2123 struct qdisc_walker w; 2124 struct sk_buff *skb; 2125 struct netlink_callback *cb; 2126 }; 2127 2128 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, 2129 struct qdisc_walker *arg) 2130 { 2131 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 2132 2133 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 2134 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2135 RTM_NEWTCLASS); 2136 } 2137 2138 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 2139 struct tcmsg *tcm, struct netlink_callback *cb, 2140 int *t_p, int s_t) 2141 { 2142 struct qdisc_dump_args arg; 2143 2144 if (tc_qdisc_dump_ignore(q, false) || 2145 *t_p < s_t || !q->ops->cl_ops || 2146 (tcm->tcm_parent && 2147 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 2148 (*t_p)++; 2149 return 0; 2150 } 2151 if (*t_p > s_t) 2152 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 2153 arg.w.fn = qdisc_class_dump; 2154 arg.skb = skb; 2155 arg.cb = cb; 2156 arg.w.stop = 0; 2157 arg.w.skip = cb->args[1]; 2158 arg.w.count = 0; 2159 q->ops->cl_ops->walk(q, &arg.w); 2160 cb->args[1] = arg.w.count; 2161 if (arg.w.stop) 2162 return -1; 2163 (*t_p)++; 2164 return 0; 2165 } 2166 2167 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 2168 struct tcmsg *tcm, struct netlink_callback *cb, 2169 int *t_p, int s_t) 2170 { 2171 struct Qdisc *q; 2172 int b; 2173 2174 if (!root) 2175 return 0; 2176 2177 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 2178 return -1; 2179 2180 if (!qdisc_dev(root)) 2181 return 0; 2182 2183 if (tcm->tcm_parent) { 2184 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent)); 2185 if (q && q != root && 2186 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2187 return -1; 2188 return 0; 2189 } 2190 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 2191 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2192 return -1; 2193 } 2194 2195 return 0; 2196 } 2197 2198 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 2199 { 2200 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2201 struct net *net = sock_net(skb->sk); 2202 struct netdev_queue *dev_queue; 2203 struct net_device *dev; 2204 int t, s_t; 2205 2206 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2207 return 0; 2208 dev = dev_get_by_index(net, tcm->tcm_ifindex); 2209 if (!dev) 2210 return 0; 2211 2212 s_t = cb->args[0]; 2213 t = 0; 2214 2215 if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0) 2216 goto done; 2217 2218 dev_queue = dev_ingress_queue(dev); 2219 if (dev_queue && 2220 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 2221 &t, s_t) < 0) 2222 goto done; 2223 2224 done: 2225 cb->args[0] = t; 2226 2227 dev_put(dev); 2228 return skb->len; 2229 } 2230 2231 #ifdef CONFIG_PROC_FS 2232 static int psched_show(struct seq_file *seq, void *v) 2233 { 2234 seq_printf(seq, "%08x %08x %08x %08x\n", 2235 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 2236 1000000, 2237 (u32)NSEC_PER_SEC / hrtimer_resolution); 2238 2239 return 0; 2240 } 2241 2242 static int __net_init psched_net_init(struct net *net) 2243 { 2244 struct proc_dir_entry *e; 2245 2246 e = proc_create_single("psched", 0, net->proc_net, psched_show); 2247 if (e == NULL) 2248 return -ENOMEM; 2249 2250 return 0; 2251 } 2252 2253 static void __net_exit psched_net_exit(struct net *net) 2254 { 2255 remove_proc_entry("psched", net->proc_net); 2256 } 2257 #else 2258 static int __net_init psched_net_init(struct net *net) 2259 { 2260 return 0; 2261 } 2262 2263 static void __net_exit psched_net_exit(struct net *net) 2264 { 2265 } 2266 #endif 2267 2268 static struct pernet_operations psched_net_ops = { 2269 .init = psched_net_init, 2270 .exit = psched_net_exit, 2271 }; 2272 2273 static int __init pktsched_init(void) 2274 { 2275 int err; 2276 2277 err = register_pernet_subsys(&psched_net_ops); 2278 if (err) { 2279 pr_err("pktsched_init: " 2280 "cannot initialize per netns operations\n"); 2281 return err; 2282 } 2283 2284 register_qdisc(&pfifo_fast_ops); 2285 register_qdisc(&pfifo_qdisc_ops); 2286 register_qdisc(&bfifo_qdisc_ops); 2287 register_qdisc(&pfifo_head_drop_qdisc_ops); 2288 register_qdisc(&mq_qdisc_ops); 2289 register_qdisc(&noqueue_qdisc_ops); 2290 2291 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0); 2292 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0); 2293 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, 2294 0); 2295 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0); 2296 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0); 2297 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, 2298 0); 2299 2300 return 0; 2301 } 2302 2303 subsys_initcall(pktsched_init); 2304