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 #include <net/tc_wrapper.h> 35 36 #include <trace/events/qdisc.h> 37 38 /* 39 40 Short review. 41 ------------- 42 43 This file consists of two interrelated parts: 44 45 1. queueing disciplines manager frontend. 46 2. traffic classes manager frontend. 47 48 Generally, queueing discipline ("qdisc") is a black box, 49 which is able to enqueue packets and to dequeue them (when 50 device is ready to send something) in order and at times 51 determined by algorithm hidden in it. 52 53 qdisc's are divided to two categories: 54 - "queues", which have no internal structure visible from outside. 55 - "schedulers", which split all the packets to "traffic classes", 56 using "packet classifiers" (look at cls_api.c) 57 58 In turn, classes may have child qdiscs (as rule, queues) 59 attached to them etc. etc. etc. 60 61 The goal of the routines in this file is to translate 62 information supplied by user in the form of handles 63 to more intelligible for kernel form, to make some sanity 64 checks and part of work, which is common to all qdiscs 65 and to provide rtnetlink notifications. 66 67 All real intelligent work is done inside qdisc modules. 68 69 70 71 Every discipline has two major routines: enqueue and dequeue. 72 73 ---dequeue 74 75 dequeue usually returns a skb to send. It is allowed to return NULL, 76 but it does not mean that queue is empty, it just means that 77 discipline does not want to send anything this time. 78 Queue is really empty if q->q.qlen == 0. 79 For complicated disciplines with multiple queues q->q is not 80 real packet queue, but however q->q.qlen must be valid. 81 82 ---enqueue 83 84 enqueue returns 0, if packet was enqueued successfully. 85 If packet (this one or another one) was dropped, it returns 86 not zero error code. 87 NET_XMIT_DROP - this packet dropped 88 Expected action: do not backoff, but wait until queue will clear. 89 NET_XMIT_CN - probably this packet enqueued, but another one dropped. 90 Expected action: backoff or ignore 91 92 Auxiliary routines: 93 94 ---peek 95 96 like dequeue but without removing a packet from the queue 97 98 ---reset 99 100 returns qdisc to initial state: purge all buffers, clear all 101 timers, counters (except for statistics) etc. 102 103 ---init 104 105 initializes newly created qdisc. 106 107 ---destroy 108 109 destroys resources allocated by init and during lifetime of qdisc. 110 111 ---change 112 113 changes qdisc parameters. 114 */ 115 116 /* Protects list of registered TC modules. It is pure SMP lock. */ 117 static DEFINE_RWLOCK(qdisc_mod_lock); 118 119 120 /************************************************ 121 * Queueing disciplines manipulation. * 122 ************************************************/ 123 124 125 /* The list of all installed queueing disciplines. */ 126 127 static struct Qdisc_ops *qdisc_base; 128 129 /* Register/unregister queueing discipline */ 130 131 int register_qdisc(struct Qdisc_ops *qops) 132 { 133 struct Qdisc_ops *q, **qp; 134 int rc = -EEXIST; 135 136 write_lock(&qdisc_mod_lock); 137 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 138 if (!strcmp(qops->id, q->id)) 139 goto out; 140 141 if (qops->enqueue == NULL) 142 qops->enqueue = noop_qdisc_ops.enqueue; 143 if (qops->peek == NULL) { 144 if (qops->dequeue == NULL) 145 qops->peek = noop_qdisc_ops.peek; 146 else 147 goto out_einval; 148 } 149 if (qops->dequeue == NULL) 150 qops->dequeue = noop_qdisc_ops.dequeue; 151 152 if (qops->cl_ops) { 153 const struct Qdisc_class_ops *cops = qops->cl_ops; 154 155 if (!(cops->find && cops->walk && cops->leaf)) 156 goto out_einval; 157 158 if (cops->tcf_block && !(cops->bind_tcf && cops->unbind_tcf)) 159 goto out_einval; 160 } 161 162 qops->next = NULL; 163 *qp = qops; 164 rc = 0; 165 out: 166 write_unlock(&qdisc_mod_lock); 167 return rc; 168 169 out_einval: 170 rc = -EINVAL; 171 goto out; 172 } 173 EXPORT_SYMBOL(register_qdisc); 174 175 void unregister_qdisc(struct Qdisc_ops *qops) 176 { 177 struct Qdisc_ops *q, **qp; 178 int err = -ENOENT; 179 180 write_lock(&qdisc_mod_lock); 181 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 182 if (q == qops) 183 break; 184 if (q) { 185 *qp = q->next; 186 q->next = NULL; 187 err = 0; 188 } 189 write_unlock(&qdisc_mod_lock); 190 191 WARN(err, "unregister qdisc(%s) failed\n", qops->id); 192 } 193 EXPORT_SYMBOL(unregister_qdisc); 194 195 /* Get default qdisc if not otherwise specified */ 196 void qdisc_get_default(char *name, size_t len) 197 { 198 read_lock(&qdisc_mod_lock); 199 strscpy(name, default_qdisc_ops->id, len); 200 read_unlock(&qdisc_mod_lock); 201 } 202 203 static struct Qdisc_ops *qdisc_lookup_default(const char *name) 204 { 205 struct Qdisc_ops *q = NULL; 206 207 for (q = qdisc_base; q; q = q->next) { 208 if (!strcmp(name, q->id)) { 209 if (!try_module_get(q->owner)) 210 q = NULL; 211 break; 212 } 213 } 214 215 return q; 216 } 217 218 /* Set new default qdisc to use */ 219 int qdisc_set_default(const char *name) 220 { 221 const struct Qdisc_ops *ops; 222 223 if (!capable(CAP_NET_ADMIN)) 224 return -EPERM; 225 226 write_lock(&qdisc_mod_lock); 227 ops = qdisc_lookup_default(name); 228 if (!ops) { 229 /* Not found, drop lock and try to load module */ 230 write_unlock(&qdisc_mod_lock); 231 request_module("sch_%s", name); 232 write_lock(&qdisc_mod_lock); 233 234 ops = qdisc_lookup_default(name); 235 } 236 237 if (ops) { 238 /* Set new default */ 239 module_put(default_qdisc_ops->owner); 240 default_qdisc_ops = ops; 241 } 242 write_unlock(&qdisc_mod_lock); 243 244 return ops ? 0 : -ENOENT; 245 } 246 247 #ifdef CONFIG_NET_SCH_DEFAULT 248 /* Set default value from kernel config */ 249 static int __init sch_default_qdisc(void) 250 { 251 return qdisc_set_default(CONFIG_DEFAULT_NET_SCH); 252 } 253 late_initcall(sch_default_qdisc); 254 #endif 255 256 /* We know handle. Find qdisc among all qdisc's attached to device 257 * (root qdisc, all its children, children of children etc.) 258 * Note: caller either uses rtnl or rcu_read_lock() 259 */ 260 261 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 262 { 263 struct Qdisc *q; 264 265 if (!qdisc_dev(root)) 266 return (root->handle == handle ? root : NULL); 267 268 if (!(root->flags & TCQ_F_BUILTIN) && 269 root->handle == handle) 270 return root; 271 272 hash_for_each_possible_rcu(qdisc_dev(root)->qdisc_hash, q, hash, handle, 273 lockdep_rtnl_is_held()) { 274 if (q->handle == handle) 275 return q; 276 } 277 return NULL; 278 } 279 280 void qdisc_hash_add(struct Qdisc *q, bool invisible) 281 { 282 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 283 ASSERT_RTNL(); 284 hash_add_rcu(qdisc_dev(q)->qdisc_hash, &q->hash, q->handle); 285 if (invisible) 286 q->flags |= TCQ_F_INVISIBLE; 287 } 288 } 289 EXPORT_SYMBOL(qdisc_hash_add); 290 291 void qdisc_hash_del(struct Qdisc *q) 292 { 293 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 294 ASSERT_RTNL(); 295 hash_del_rcu(&q->hash); 296 } 297 } 298 EXPORT_SYMBOL(qdisc_hash_del); 299 300 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 301 { 302 struct Qdisc *q; 303 304 if (!handle) 305 return NULL; 306 q = qdisc_match_from_root(rtnl_dereference(dev->qdisc), handle); 307 if (q) 308 goto out; 309 310 if (dev_ingress_queue(dev)) 311 q = qdisc_match_from_root( 312 dev_ingress_queue(dev)->qdisc_sleeping, 313 handle); 314 out: 315 return q; 316 } 317 318 struct Qdisc *qdisc_lookup_rcu(struct net_device *dev, u32 handle) 319 { 320 struct netdev_queue *nq; 321 struct Qdisc *q; 322 323 if (!handle) 324 return NULL; 325 q = qdisc_match_from_root(rcu_dereference(dev->qdisc), handle); 326 if (q) 327 goto out; 328 329 nq = dev_ingress_queue_rcu(dev); 330 if (nq) 331 q = qdisc_match_from_root(nq->qdisc_sleeping, handle); 332 out: 333 return q; 334 } 335 336 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 337 { 338 unsigned long cl; 339 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 340 341 if (cops == NULL) 342 return NULL; 343 cl = cops->find(p, classid); 344 345 if (cl == 0) 346 return NULL; 347 return cops->leaf(p, cl); 348 } 349 350 /* Find queueing discipline by name */ 351 352 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 353 { 354 struct Qdisc_ops *q = NULL; 355 356 if (kind) { 357 read_lock(&qdisc_mod_lock); 358 for (q = qdisc_base; q; q = q->next) { 359 if (nla_strcmp(kind, q->id) == 0) { 360 if (!try_module_get(q->owner)) 361 q = NULL; 362 break; 363 } 364 } 365 read_unlock(&qdisc_mod_lock); 366 } 367 return q; 368 } 369 370 /* The linklayer setting were not transferred from iproute2, in older 371 * versions, and the rate tables lookup systems have been dropped in 372 * the kernel. To keep backward compatible with older iproute2 tc 373 * utils, we detect the linklayer setting by detecting if the rate 374 * table were modified. 375 * 376 * For linklayer ATM table entries, the rate table will be aligned to 377 * 48 bytes, thus some table entries will contain the same value. The 378 * mpu (min packet unit) is also encoded into the old rate table, thus 379 * starting from the mpu, we find low and high table entries for 380 * mapping this cell. If these entries contain the same value, when 381 * the rate tables have been modified for linklayer ATM. 382 * 383 * This is done by rounding mpu to the nearest 48 bytes cell/entry, 384 * and then roundup to the next cell, calc the table entry one below, 385 * and compare. 386 */ 387 static __u8 __detect_linklayer(struct tc_ratespec *r, __u32 *rtab) 388 { 389 int low = roundup(r->mpu, 48); 390 int high = roundup(low+1, 48); 391 int cell_low = low >> r->cell_log; 392 int cell_high = (high >> r->cell_log) - 1; 393 394 /* rtab is too inaccurate at rates > 100Mbit/s */ 395 if ((r->rate > (100000000/8)) || (rtab[0] == 0)) { 396 pr_debug("TC linklayer: Giving up ATM detection\n"); 397 return TC_LINKLAYER_ETHERNET; 398 } 399 400 if ((cell_high > cell_low) && (cell_high < 256) 401 && (rtab[cell_low] == rtab[cell_high])) { 402 pr_debug("TC linklayer: Detected ATM, low(%d)=high(%d)=%u\n", 403 cell_low, cell_high, rtab[cell_high]); 404 return TC_LINKLAYER_ATM; 405 } 406 return TC_LINKLAYER_ETHERNET; 407 } 408 409 static struct qdisc_rate_table *qdisc_rtab_list; 410 411 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, 412 struct nlattr *tab, 413 struct netlink_ext_ack *extack) 414 { 415 struct qdisc_rate_table *rtab; 416 417 if (tab == NULL || r->rate == 0 || 418 r->cell_log == 0 || r->cell_log >= 32 || 419 nla_len(tab) != TC_RTAB_SIZE) { 420 NL_SET_ERR_MSG(extack, "Invalid rate table parameters for searching"); 421 return NULL; 422 } 423 424 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 425 if (!memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) && 426 !memcmp(&rtab->data, nla_data(tab), 1024)) { 427 rtab->refcnt++; 428 return rtab; 429 } 430 } 431 432 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 433 if (rtab) { 434 rtab->rate = *r; 435 rtab->refcnt = 1; 436 memcpy(rtab->data, nla_data(tab), 1024); 437 if (r->linklayer == TC_LINKLAYER_UNAWARE) 438 r->linklayer = __detect_linklayer(r, rtab->data); 439 rtab->next = qdisc_rtab_list; 440 qdisc_rtab_list = rtab; 441 } else { 442 NL_SET_ERR_MSG(extack, "Failed to allocate new qdisc rate table"); 443 } 444 return rtab; 445 } 446 EXPORT_SYMBOL(qdisc_get_rtab); 447 448 void qdisc_put_rtab(struct qdisc_rate_table *tab) 449 { 450 struct qdisc_rate_table *rtab, **rtabp; 451 452 if (!tab || --tab->refcnt) 453 return; 454 455 for (rtabp = &qdisc_rtab_list; 456 (rtab = *rtabp) != NULL; 457 rtabp = &rtab->next) { 458 if (rtab == tab) { 459 *rtabp = rtab->next; 460 kfree(rtab); 461 return; 462 } 463 } 464 } 465 EXPORT_SYMBOL(qdisc_put_rtab); 466 467 static LIST_HEAD(qdisc_stab_list); 468 469 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 470 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 471 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 472 }; 473 474 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt, 475 struct netlink_ext_ack *extack) 476 { 477 struct nlattr *tb[TCA_STAB_MAX + 1]; 478 struct qdisc_size_table *stab; 479 struct tc_sizespec *s; 480 unsigned int tsize = 0; 481 u16 *tab = NULL; 482 int err; 483 484 err = nla_parse_nested_deprecated(tb, TCA_STAB_MAX, opt, stab_policy, 485 extack); 486 if (err < 0) 487 return ERR_PTR(err); 488 if (!tb[TCA_STAB_BASE]) { 489 NL_SET_ERR_MSG(extack, "Size table base attribute is missing"); 490 return ERR_PTR(-EINVAL); 491 } 492 493 s = nla_data(tb[TCA_STAB_BASE]); 494 495 if (s->tsize > 0) { 496 if (!tb[TCA_STAB_DATA]) { 497 NL_SET_ERR_MSG(extack, "Size table data attribute is missing"); 498 return ERR_PTR(-EINVAL); 499 } 500 tab = nla_data(tb[TCA_STAB_DATA]); 501 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 502 } 503 504 if (tsize != s->tsize || (!tab && tsize > 0)) { 505 NL_SET_ERR_MSG(extack, "Invalid size of size table"); 506 return ERR_PTR(-EINVAL); 507 } 508 509 list_for_each_entry(stab, &qdisc_stab_list, list) { 510 if (memcmp(&stab->szopts, s, sizeof(*s))) 511 continue; 512 if (tsize > 0 && 513 memcmp(stab->data, tab, flex_array_size(stab, data, tsize))) 514 continue; 515 stab->refcnt++; 516 return stab; 517 } 518 519 if (s->size_log > STAB_SIZE_LOG_MAX || 520 s->cell_log > STAB_SIZE_LOG_MAX) { 521 NL_SET_ERR_MSG(extack, "Invalid logarithmic size of size table"); 522 return ERR_PTR(-EINVAL); 523 } 524 525 stab = kmalloc(struct_size(stab, data, tsize), GFP_KERNEL); 526 if (!stab) 527 return ERR_PTR(-ENOMEM); 528 529 stab->refcnt = 1; 530 stab->szopts = *s; 531 if (tsize > 0) 532 memcpy(stab->data, tab, flex_array_size(stab, data, tsize)); 533 534 list_add_tail(&stab->list, &qdisc_stab_list); 535 536 return stab; 537 } 538 539 void qdisc_put_stab(struct qdisc_size_table *tab) 540 { 541 if (!tab) 542 return; 543 544 if (--tab->refcnt == 0) { 545 list_del(&tab->list); 546 kfree_rcu(tab, rcu); 547 } 548 } 549 EXPORT_SYMBOL(qdisc_put_stab); 550 551 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 552 { 553 struct nlattr *nest; 554 555 nest = nla_nest_start_noflag(skb, TCA_STAB); 556 if (nest == NULL) 557 goto nla_put_failure; 558 if (nla_put(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts)) 559 goto nla_put_failure; 560 nla_nest_end(skb, nest); 561 562 return skb->len; 563 564 nla_put_failure: 565 return -1; 566 } 567 568 void __qdisc_calculate_pkt_len(struct sk_buff *skb, 569 const struct qdisc_size_table *stab) 570 { 571 int pkt_len, slot; 572 573 pkt_len = skb->len + stab->szopts.overhead; 574 if (unlikely(!stab->szopts.tsize)) 575 goto out; 576 577 slot = pkt_len + stab->szopts.cell_align; 578 if (unlikely(slot < 0)) 579 slot = 0; 580 581 slot >>= stab->szopts.cell_log; 582 if (likely(slot < stab->szopts.tsize)) 583 pkt_len = stab->data[slot]; 584 else 585 pkt_len = stab->data[stab->szopts.tsize - 1] * 586 (slot / stab->szopts.tsize) + 587 stab->data[slot % stab->szopts.tsize]; 588 589 pkt_len <<= stab->szopts.size_log; 590 out: 591 if (unlikely(pkt_len < 1)) 592 pkt_len = 1; 593 qdisc_skb_cb(skb)->pkt_len = pkt_len; 594 } 595 EXPORT_SYMBOL(__qdisc_calculate_pkt_len); 596 597 void qdisc_warn_nonwc(const char *txt, struct Qdisc *qdisc) 598 { 599 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { 600 pr_warn("%s: %s qdisc %X: is non-work-conserving?\n", 601 txt, qdisc->ops->id, qdisc->handle >> 16); 602 qdisc->flags |= TCQ_F_WARN_NONWC; 603 } 604 } 605 EXPORT_SYMBOL(qdisc_warn_nonwc); 606 607 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 608 { 609 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 610 timer); 611 612 rcu_read_lock(); 613 __netif_schedule(qdisc_root(wd->qdisc)); 614 rcu_read_unlock(); 615 616 return HRTIMER_NORESTART; 617 } 618 619 void qdisc_watchdog_init_clockid(struct qdisc_watchdog *wd, struct Qdisc *qdisc, 620 clockid_t clockid) 621 { 622 hrtimer_init(&wd->timer, clockid, HRTIMER_MODE_ABS_PINNED); 623 wd->timer.function = qdisc_watchdog; 624 wd->qdisc = qdisc; 625 } 626 EXPORT_SYMBOL(qdisc_watchdog_init_clockid); 627 628 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc) 629 { 630 qdisc_watchdog_init_clockid(wd, qdisc, CLOCK_MONOTONIC); 631 } 632 EXPORT_SYMBOL(qdisc_watchdog_init); 633 634 void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires, 635 u64 delta_ns) 636 { 637 if (test_bit(__QDISC_STATE_DEACTIVATED, 638 &qdisc_root_sleeping(wd->qdisc)->state)) 639 return; 640 641 if (hrtimer_is_queued(&wd->timer)) { 642 /* If timer is already set in [expires, expires + delta_ns], 643 * do not reprogram it. 644 */ 645 if (wd->last_expires - expires <= delta_ns) 646 return; 647 } 648 649 wd->last_expires = expires; 650 hrtimer_start_range_ns(&wd->timer, 651 ns_to_ktime(expires), 652 delta_ns, 653 HRTIMER_MODE_ABS_PINNED); 654 } 655 EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns); 656 657 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 658 { 659 hrtimer_cancel(&wd->timer); 660 } 661 EXPORT_SYMBOL(qdisc_watchdog_cancel); 662 663 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 664 { 665 struct hlist_head *h; 666 unsigned int i; 667 668 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL); 669 670 if (h != NULL) { 671 for (i = 0; i < n; i++) 672 INIT_HLIST_HEAD(&h[i]); 673 } 674 return h; 675 } 676 677 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 678 { 679 struct Qdisc_class_common *cl; 680 struct hlist_node *next; 681 struct hlist_head *nhash, *ohash; 682 unsigned int nsize, nmask, osize; 683 unsigned int i, h; 684 685 /* Rehash when load factor exceeds 0.75 */ 686 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 687 return; 688 nsize = clhash->hashsize * 2; 689 nmask = nsize - 1; 690 nhash = qdisc_class_hash_alloc(nsize); 691 if (nhash == NULL) 692 return; 693 694 ohash = clhash->hash; 695 osize = clhash->hashsize; 696 697 sch_tree_lock(sch); 698 for (i = 0; i < osize; i++) { 699 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) { 700 h = qdisc_class_hash(cl->classid, nmask); 701 hlist_add_head(&cl->hnode, &nhash[h]); 702 } 703 } 704 clhash->hash = nhash; 705 clhash->hashsize = nsize; 706 clhash->hashmask = nmask; 707 sch_tree_unlock(sch); 708 709 kvfree(ohash); 710 } 711 EXPORT_SYMBOL(qdisc_class_hash_grow); 712 713 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 714 { 715 unsigned int size = 4; 716 717 clhash->hash = qdisc_class_hash_alloc(size); 718 if (!clhash->hash) 719 return -ENOMEM; 720 clhash->hashsize = size; 721 clhash->hashmask = size - 1; 722 clhash->hashelems = 0; 723 return 0; 724 } 725 EXPORT_SYMBOL(qdisc_class_hash_init); 726 727 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 728 { 729 kvfree(clhash->hash); 730 } 731 EXPORT_SYMBOL(qdisc_class_hash_destroy); 732 733 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 734 struct Qdisc_class_common *cl) 735 { 736 unsigned int h; 737 738 INIT_HLIST_NODE(&cl->hnode); 739 h = qdisc_class_hash(cl->classid, clhash->hashmask); 740 hlist_add_head(&cl->hnode, &clhash->hash[h]); 741 clhash->hashelems++; 742 } 743 EXPORT_SYMBOL(qdisc_class_hash_insert); 744 745 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 746 struct Qdisc_class_common *cl) 747 { 748 hlist_del(&cl->hnode); 749 clhash->hashelems--; 750 } 751 EXPORT_SYMBOL(qdisc_class_hash_remove); 752 753 /* Allocate an unique handle from space managed by kernel 754 * Possible range is [8000-FFFF]:0000 (0x8000 values) 755 */ 756 static u32 qdisc_alloc_handle(struct net_device *dev) 757 { 758 int i = 0x8000; 759 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 760 761 do { 762 autohandle += TC_H_MAKE(0x10000U, 0); 763 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 764 autohandle = TC_H_MAKE(0x80000000U, 0); 765 if (!qdisc_lookup(dev, autohandle)) 766 return autohandle; 767 cond_resched(); 768 } while (--i > 0); 769 770 return 0; 771 } 772 773 void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len) 774 { 775 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED; 776 const struct Qdisc_class_ops *cops; 777 unsigned long cl; 778 u32 parentid; 779 bool notify; 780 int drops; 781 782 if (n == 0 && len == 0) 783 return; 784 drops = max_t(int, n, 0); 785 rcu_read_lock(); 786 while ((parentid = sch->parent)) { 787 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 788 break; 789 790 if (sch->flags & TCQ_F_NOPARENT) 791 break; 792 /* Notify parent qdisc only if child qdisc becomes empty. 793 * 794 * If child was empty even before update then backlog 795 * counter is screwed and we skip notification because 796 * parent class is already passive. 797 * 798 * If the original child was offloaded then it is allowed 799 * to be seem as empty, so the parent is notified anyway. 800 */ 801 notify = !sch->q.qlen && !WARN_ON_ONCE(!n && 802 !qdisc_is_offloaded); 803 /* TODO: perform the search on a per txq basis */ 804 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 805 if (sch == NULL) { 806 WARN_ON_ONCE(parentid != TC_H_ROOT); 807 break; 808 } 809 cops = sch->ops->cl_ops; 810 if (notify && cops->qlen_notify) { 811 cl = cops->find(sch, parentid); 812 cops->qlen_notify(sch, cl); 813 } 814 sch->q.qlen -= n; 815 sch->qstats.backlog -= len; 816 __qdisc_qstats_drop(sch, drops); 817 } 818 rcu_read_unlock(); 819 } 820 EXPORT_SYMBOL(qdisc_tree_reduce_backlog); 821 822 int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type, 823 void *type_data) 824 { 825 struct net_device *dev = qdisc_dev(sch); 826 int err; 827 828 sch->flags &= ~TCQ_F_OFFLOADED; 829 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 830 return 0; 831 832 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 833 if (err == -EOPNOTSUPP) 834 return 0; 835 836 if (!err) 837 sch->flags |= TCQ_F_OFFLOADED; 838 839 return err; 840 } 841 EXPORT_SYMBOL(qdisc_offload_dump_helper); 842 843 void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch, 844 struct Qdisc *new, struct Qdisc *old, 845 enum tc_setup_type type, void *type_data, 846 struct netlink_ext_ack *extack) 847 { 848 bool any_qdisc_is_offloaded; 849 int err; 850 851 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 852 return; 853 854 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 855 856 /* Don't report error if the graft is part of destroy operation. */ 857 if (!err || !new || new == &noop_qdisc) 858 return; 859 860 /* Don't report error if the parent, the old child and the new 861 * one are not offloaded. 862 */ 863 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED; 864 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED; 865 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED; 866 867 if (any_qdisc_is_offloaded) 868 NL_SET_ERR_MSG(extack, "Offloading graft operation failed."); 869 } 870 EXPORT_SYMBOL(qdisc_offload_graft_helper); 871 872 void qdisc_offload_query_caps(struct net_device *dev, 873 enum tc_setup_type type, 874 void *caps, size_t caps_len) 875 { 876 const struct net_device_ops *ops = dev->netdev_ops; 877 struct tc_query_caps_base base = { 878 .type = type, 879 .caps = caps, 880 }; 881 882 memset(caps, 0, caps_len); 883 884 if (ops->ndo_setup_tc) 885 ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base); 886 } 887 EXPORT_SYMBOL(qdisc_offload_query_caps); 888 889 static void qdisc_offload_graft_root(struct net_device *dev, 890 struct Qdisc *new, struct Qdisc *old, 891 struct netlink_ext_ack *extack) 892 { 893 struct tc_root_qopt_offload graft_offload = { 894 .command = TC_ROOT_GRAFT, 895 .handle = new ? new->handle : 0, 896 .ingress = (new && new->flags & TCQ_F_INGRESS) || 897 (old && old->flags & TCQ_F_INGRESS), 898 }; 899 900 qdisc_offload_graft_helper(dev, NULL, new, old, 901 TC_SETUP_ROOT_QDISC, &graft_offload, extack); 902 } 903 904 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 905 u32 portid, u32 seq, u16 flags, int event) 906 { 907 struct gnet_stats_basic_sync __percpu *cpu_bstats = NULL; 908 struct gnet_stats_queue __percpu *cpu_qstats = NULL; 909 struct tcmsg *tcm; 910 struct nlmsghdr *nlh; 911 unsigned char *b = skb_tail_pointer(skb); 912 struct gnet_dump d; 913 struct qdisc_size_table *stab; 914 u32 block_index; 915 __u32 qlen; 916 917 cond_resched(); 918 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 919 if (!nlh) 920 goto out_nlmsg_trim; 921 tcm = nlmsg_data(nlh); 922 tcm->tcm_family = AF_UNSPEC; 923 tcm->tcm__pad1 = 0; 924 tcm->tcm__pad2 = 0; 925 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 926 tcm->tcm_parent = clid; 927 tcm->tcm_handle = q->handle; 928 tcm->tcm_info = refcount_read(&q->refcnt); 929 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 930 goto nla_put_failure; 931 if (q->ops->ingress_block_get) { 932 block_index = q->ops->ingress_block_get(q); 933 if (block_index && 934 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index)) 935 goto nla_put_failure; 936 } 937 if (q->ops->egress_block_get) { 938 block_index = q->ops->egress_block_get(q); 939 if (block_index && 940 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index)) 941 goto nla_put_failure; 942 } 943 if (q->ops->dump && q->ops->dump(q, skb) < 0) 944 goto nla_put_failure; 945 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED))) 946 goto nla_put_failure; 947 qlen = qdisc_qlen_sum(q); 948 949 stab = rtnl_dereference(q->stab); 950 if (stab && qdisc_dump_stab(skb, stab) < 0) 951 goto nla_put_failure; 952 953 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 954 NULL, &d, TCA_PAD) < 0) 955 goto nla_put_failure; 956 957 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 958 goto nla_put_failure; 959 960 if (qdisc_is_percpu_stats(q)) { 961 cpu_bstats = q->cpu_bstats; 962 cpu_qstats = q->cpu_qstats; 963 } 964 965 if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats, true) < 0 || 966 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 967 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0) 968 goto nla_put_failure; 969 970 if (gnet_stats_finish_copy(&d) < 0) 971 goto nla_put_failure; 972 973 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 974 return skb->len; 975 976 out_nlmsg_trim: 977 nla_put_failure: 978 nlmsg_trim(skb, b); 979 return -1; 980 } 981 982 static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible) 983 { 984 if (q->flags & TCQ_F_BUILTIN) 985 return true; 986 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible) 987 return true; 988 989 return false; 990 } 991 992 static int qdisc_notify(struct net *net, struct sk_buff *oskb, 993 struct nlmsghdr *n, u32 clid, 994 struct Qdisc *old, struct Qdisc *new) 995 { 996 struct sk_buff *skb; 997 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 998 999 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1000 if (!skb) 1001 return -ENOBUFS; 1002 1003 if (old && !tc_qdisc_dump_ignore(old, false)) { 1004 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq, 1005 0, RTM_DELQDISC) < 0) 1006 goto err_out; 1007 } 1008 if (new && !tc_qdisc_dump_ignore(new, false)) { 1009 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq, 1010 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1011 goto err_out; 1012 } 1013 1014 if (skb->len) 1015 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1016 n->nlmsg_flags & NLM_F_ECHO); 1017 1018 err_out: 1019 kfree_skb(skb); 1020 return -EINVAL; 1021 } 1022 1023 static void notify_and_destroy(struct net *net, struct sk_buff *skb, 1024 struct nlmsghdr *n, u32 clid, 1025 struct Qdisc *old, struct Qdisc *new) 1026 { 1027 if (new || old) 1028 qdisc_notify(net, skb, n, clid, old, new); 1029 1030 if (old) 1031 qdisc_put(old); 1032 } 1033 1034 static void qdisc_clear_nolock(struct Qdisc *sch) 1035 { 1036 sch->flags &= ~TCQ_F_NOLOCK; 1037 if (!(sch->flags & TCQ_F_CPUSTATS)) 1038 return; 1039 1040 free_percpu(sch->cpu_bstats); 1041 free_percpu(sch->cpu_qstats); 1042 sch->cpu_bstats = NULL; 1043 sch->cpu_qstats = NULL; 1044 sch->flags &= ~TCQ_F_CPUSTATS; 1045 } 1046 1047 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 1048 * to device "dev". 1049 * 1050 * When appropriate send a netlink notification using 'skb' 1051 * and "n". 1052 * 1053 * On success, destroy old qdisc. 1054 */ 1055 1056 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 1057 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 1058 struct Qdisc *new, struct Qdisc *old, 1059 struct netlink_ext_ack *extack) 1060 { 1061 struct Qdisc *q = old; 1062 struct net *net = dev_net(dev); 1063 1064 if (parent == NULL) { 1065 unsigned int i, num_q, ingress; 1066 1067 ingress = 0; 1068 num_q = dev->num_tx_queues; 1069 if ((q && q->flags & TCQ_F_INGRESS) || 1070 (new && new->flags & TCQ_F_INGRESS)) { 1071 num_q = 1; 1072 ingress = 1; 1073 if (!dev_ingress_queue(dev)) { 1074 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue"); 1075 return -ENOENT; 1076 } 1077 } 1078 1079 if (dev->flags & IFF_UP) 1080 dev_deactivate(dev); 1081 1082 qdisc_offload_graft_root(dev, new, old, extack); 1083 1084 if (new && new->ops->attach && !ingress) 1085 goto skip; 1086 1087 for (i = 0; i < num_q; i++) { 1088 struct netdev_queue *dev_queue = dev_ingress_queue(dev); 1089 1090 if (!ingress) 1091 dev_queue = netdev_get_tx_queue(dev, i); 1092 1093 old = dev_graft_qdisc(dev_queue, new); 1094 if (new && i > 0) 1095 qdisc_refcount_inc(new); 1096 1097 if (!ingress) 1098 qdisc_put(old); 1099 } 1100 1101 skip: 1102 if (!ingress) { 1103 old = rtnl_dereference(dev->qdisc); 1104 if (new && !new->ops->attach) 1105 qdisc_refcount_inc(new); 1106 rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc); 1107 1108 notify_and_destroy(net, skb, n, classid, old, new); 1109 1110 if (new && new->ops->attach) 1111 new->ops->attach(new); 1112 } else { 1113 notify_and_destroy(net, skb, n, classid, old, new); 1114 } 1115 1116 if (dev->flags & IFF_UP) 1117 dev_activate(dev); 1118 } else { 1119 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 1120 unsigned long cl; 1121 int err; 1122 1123 /* Only support running class lockless if parent is lockless */ 1124 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK)) 1125 qdisc_clear_nolock(new); 1126 1127 if (!cops || !cops->graft) 1128 return -EOPNOTSUPP; 1129 1130 cl = cops->find(parent, classid); 1131 if (!cl) { 1132 NL_SET_ERR_MSG(extack, "Specified class not found"); 1133 return -ENOENT; 1134 } 1135 1136 if (new && new->ops == &noqueue_qdisc_ops) { 1137 NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class"); 1138 return -EINVAL; 1139 } 1140 1141 err = cops->graft(parent, cl, new, &old, extack); 1142 if (err) 1143 return err; 1144 notify_and_destroy(net, skb, n, classid, old, new); 1145 } 1146 return 0; 1147 } 1148 1149 static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca, 1150 struct netlink_ext_ack *extack) 1151 { 1152 u32 block_index; 1153 1154 if (tca[TCA_INGRESS_BLOCK]) { 1155 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]); 1156 1157 if (!block_index) { 1158 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0"); 1159 return -EINVAL; 1160 } 1161 if (!sch->ops->ingress_block_set) { 1162 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported"); 1163 return -EOPNOTSUPP; 1164 } 1165 sch->ops->ingress_block_set(sch, block_index); 1166 } 1167 if (tca[TCA_EGRESS_BLOCK]) { 1168 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]); 1169 1170 if (!block_index) { 1171 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0"); 1172 return -EINVAL; 1173 } 1174 if (!sch->ops->egress_block_set) { 1175 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported"); 1176 return -EOPNOTSUPP; 1177 } 1178 sch->ops->egress_block_set(sch, block_index); 1179 } 1180 return 0; 1181 } 1182 1183 /* 1184 Allocate and initialize new qdisc. 1185 1186 Parameters are passed via opt. 1187 */ 1188 1189 static struct Qdisc *qdisc_create(struct net_device *dev, 1190 struct netdev_queue *dev_queue, 1191 u32 parent, u32 handle, 1192 struct nlattr **tca, int *errp, 1193 struct netlink_ext_ack *extack) 1194 { 1195 int err; 1196 struct nlattr *kind = tca[TCA_KIND]; 1197 struct Qdisc *sch; 1198 struct Qdisc_ops *ops; 1199 struct qdisc_size_table *stab; 1200 1201 ops = qdisc_lookup_ops(kind); 1202 #ifdef CONFIG_MODULES 1203 if (ops == NULL && kind != NULL) { 1204 char name[IFNAMSIZ]; 1205 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) { 1206 /* We dropped the RTNL semaphore in order to 1207 * perform the module load. So, even if we 1208 * succeeded in loading the module we have to 1209 * tell the caller to replay the request. We 1210 * indicate this using -EAGAIN. 1211 * We replay the request because the device may 1212 * go away in the mean time. 1213 */ 1214 rtnl_unlock(); 1215 request_module("sch_%s", name); 1216 rtnl_lock(); 1217 ops = qdisc_lookup_ops(kind); 1218 if (ops != NULL) { 1219 /* We will try again qdisc_lookup_ops, 1220 * so don't keep a reference. 1221 */ 1222 module_put(ops->owner); 1223 err = -EAGAIN; 1224 goto err_out; 1225 } 1226 } 1227 } 1228 #endif 1229 1230 err = -ENOENT; 1231 if (!ops) { 1232 NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown"); 1233 goto err_out; 1234 } 1235 1236 sch = qdisc_alloc(dev_queue, ops, extack); 1237 if (IS_ERR(sch)) { 1238 err = PTR_ERR(sch); 1239 goto err_out2; 1240 } 1241 1242 sch->parent = parent; 1243 1244 if (handle == TC_H_INGRESS) { 1245 sch->flags |= TCQ_F_INGRESS; 1246 handle = TC_H_MAKE(TC_H_INGRESS, 0); 1247 } else { 1248 if (handle == 0) { 1249 handle = qdisc_alloc_handle(dev); 1250 if (handle == 0) { 1251 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded"); 1252 err = -ENOSPC; 1253 goto err_out3; 1254 } 1255 } 1256 if (!netif_is_multiqueue(dev)) 1257 sch->flags |= TCQ_F_ONETXQUEUE; 1258 } 1259 1260 sch->handle = handle; 1261 1262 /* This exist to keep backward compatible with a userspace 1263 * loophole, what allowed userspace to get IFF_NO_QUEUE 1264 * facility on older kernels by setting tx_queue_len=0 (prior 1265 * to qdisc init), and then forgot to reinit tx_queue_len 1266 * before again attaching a qdisc. 1267 */ 1268 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) { 1269 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 1270 netdev_info(dev, "Caught tx_queue_len zero misconfig\n"); 1271 } 1272 1273 err = qdisc_block_indexes_set(sch, tca, extack); 1274 if (err) 1275 goto err_out3; 1276 1277 if (ops->init) { 1278 err = ops->init(sch, tca[TCA_OPTIONS], extack); 1279 if (err != 0) 1280 goto err_out5; 1281 } 1282 1283 if (tca[TCA_STAB]) { 1284 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1285 if (IS_ERR(stab)) { 1286 err = PTR_ERR(stab); 1287 goto err_out4; 1288 } 1289 rcu_assign_pointer(sch->stab, stab); 1290 } 1291 if (tca[TCA_RATE]) { 1292 err = -EOPNOTSUPP; 1293 if (sch->flags & TCQ_F_MQROOT) { 1294 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc"); 1295 goto err_out4; 1296 } 1297 1298 err = gen_new_estimator(&sch->bstats, 1299 sch->cpu_bstats, 1300 &sch->rate_est, 1301 NULL, 1302 true, 1303 tca[TCA_RATE]); 1304 if (err) { 1305 NL_SET_ERR_MSG(extack, "Failed to generate new estimator"); 1306 goto err_out4; 1307 } 1308 } 1309 1310 qdisc_hash_add(sch, false); 1311 trace_qdisc_create(ops, dev, parent); 1312 1313 return sch; 1314 1315 err_out5: 1316 /* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */ 1317 if (ops->destroy) 1318 ops->destroy(sch); 1319 err_out3: 1320 netdev_put(dev, &sch->dev_tracker); 1321 qdisc_free(sch); 1322 err_out2: 1323 module_put(ops->owner); 1324 err_out: 1325 *errp = err; 1326 return NULL; 1327 1328 err_out4: 1329 /* 1330 * Any broken qdiscs that would require a ops->reset() here? 1331 * The qdisc was never in action so it shouldn't be necessary. 1332 */ 1333 qdisc_put_stab(rtnl_dereference(sch->stab)); 1334 if (ops->destroy) 1335 ops->destroy(sch); 1336 goto err_out3; 1337 } 1338 1339 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca, 1340 struct netlink_ext_ack *extack) 1341 { 1342 struct qdisc_size_table *ostab, *stab = NULL; 1343 int err = 0; 1344 1345 if (tca[TCA_OPTIONS]) { 1346 if (!sch->ops->change) { 1347 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc"); 1348 return -EINVAL; 1349 } 1350 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 1351 NL_SET_ERR_MSG(extack, "Change of blocks is not supported"); 1352 return -EOPNOTSUPP; 1353 } 1354 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack); 1355 if (err) 1356 return err; 1357 } 1358 1359 if (tca[TCA_STAB]) { 1360 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1361 if (IS_ERR(stab)) 1362 return PTR_ERR(stab); 1363 } 1364 1365 ostab = rtnl_dereference(sch->stab); 1366 rcu_assign_pointer(sch->stab, stab); 1367 qdisc_put_stab(ostab); 1368 1369 if (tca[TCA_RATE]) { 1370 /* NB: ignores errors from replace_estimator 1371 because change can't be undone. */ 1372 if (sch->flags & TCQ_F_MQROOT) 1373 goto out; 1374 gen_replace_estimator(&sch->bstats, 1375 sch->cpu_bstats, 1376 &sch->rate_est, 1377 NULL, 1378 true, 1379 tca[TCA_RATE]); 1380 } 1381 out: 1382 return 0; 1383 } 1384 1385 struct check_loop_arg { 1386 struct qdisc_walker w; 1387 struct Qdisc *p; 1388 int depth; 1389 }; 1390 1391 static int check_loop_fn(struct Qdisc *q, unsigned long cl, 1392 struct qdisc_walker *w); 1393 1394 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 1395 { 1396 struct check_loop_arg arg; 1397 1398 if (q->ops->cl_ops == NULL) 1399 return 0; 1400 1401 arg.w.stop = arg.w.skip = arg.w.count = 0; 1402 arg.w.fn = check_loop_fn; 1403 arg.depth = depth; 1404 arg.p = p; 1405 q->ops->cl_ops->walk(q, &arg.w); 1406 return arg.w.stop ? -ELOOP : 0; 1407 } 1408 1409 static int 1410 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 1411 { 1412 struct Qdisc *leaf; 1413 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1414 struct check_loop_arg *arg = (struct check_loop_arg *)w; 1415 1416 leaf = cops->leaf(q, cl); 1417 if (leaf) { 1418 if (leaf == arg->p || arg->depth > 7) 1419 return -ELOOP; 1420 return check_loop(leaf, arg->p, arg->depth + 1); 1421 } 1422 return 0; 1423 } 1424 1425 const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = { 1426 [TCA_KIND] = { .type = NLA_STRING }, 1427 [TCA_RATE] = { .type = NLA_BINARY, 1428 .len = sizeof(struct tc_estimator) }, 1429 [TCA_STAB] = { .type = NLA_NESTED }, 1430 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG }, 1431 [TCA_CHAIN] = { .type = NLA_U32 }, 1432 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 }, 1433 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 }, 1434 }; 1435 1436 /* 1437 * Delete/get qdisc. 1438 */ 1439 1440 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1441 struct netlink_ext_ack *extack) 1442 { 1443 struct net *net = sock_net(skb->sk); 1444 struct tcmsg *tcm = nlmsg_data(n); 1445 struct nlattr *tca[TCA_MAX + 1]; 1446 struct net_device *dev; 1447 u32 clid; 1448 struct Qdisc *q = NULL; 1449 struct Qdisc *p = NULL; 1450 int err; 1451 1452 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1453 rtm_tca_policy, extack); 1454 if (err < 0) 1455 return err; 1456 1457 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1458 if (!dev) 1459 return -ENODEV; 1460 1461 clid = tcm->tcm_parent; 1462 if (clid) { 1463 if (clid != TC_H_ROOT) { 1464 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1465 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1466 if (!p) { 1467 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid"); 1468 return -ENOENT; 1469 } 1470 q = qdisc_leaf(p, clid); 1471 } else if (dev_ingress_queue(dev)) { 1472 q = dev_ingress_queue(dev)->qdisc_sleeping; 1473 } 1474 } else { 1475 q = rtnl_dereference(dev->qdisc); 1476 } 1477 if (!q) { 1478 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); 1479 return -ENOENT; 1480 } 1481 1482 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) { 1483 NL_SET_ERR_MSG(extack, "Invalid handle"); 1484 return -EINVAL; 1485 } 1486 } else { 1487 q = qdisc_lookup(dev, tcm->tcm_handle); 1488 if (!q) { 1489 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle"); 1490 return -ENOENT; 1491 } 1492 } 1493 1494 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1495 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1496 return -EINVAL; 1497 } 1498 1499 if (n->nlmsg_type == RTM_DELQDISC) { 1500 if (!clid) { 1501 NL_SET_ERR_MSG(extack, "Classid cannot be zero"); 1502 return -EINVAL; 1503 } 1504 if (q->handle == 0) { 1505 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero"); 1506 return -ENOENT; 1507 } 1508 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack); 1509 if (err != 0) 1510 return err; 1511 } else { 1512 qdisc_notify(net, skb, n, clid, NULL, q); 1513 } 1514 return 0; 1515 } 1516 1517 /* 1518 * Create/change qdisc. 1519 */ 1520 1521 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1522 struct netlink_ext_ack *extack) 1523 { 1524 struct net *net = sock_net(skb->sk); 1525 struct tcmsg *tcm; 1526 struct nlattr *tca[TCA_MAX + 1]; 1527 struct net_device *dev; 1528 u32 clid; 1529 struct Qdisc *q, *p; 1530 int err; 1531 1532 replay: 1533 /* Reinit, just in case something touches this. */ 1534 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1535 rtm_tca_policy, extack); 1536 if (err < 0) 1537 return err; 1538 1539 tcm = nlmsg_data(n); 1540 clid = tcm->tcm_parent; 1541 q = p = NULL; 1542 1543 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1544 if (!dev) 1545 return -ENODEV; 1546 1547 1548 if (clid) { 1549 if (clid != TC_H_ROOT) { 1550 if (clid != TC_H_INGRESS) { 1551 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1552 if (!p) { 1553 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); 1554 return -ENOENT; 1555 } 1556 q = qdisc_leaf(p, clid); 1557 } else if (dev_ingress_queue_create(dev)) { 1558 q = dev_ingress_queue(dev)->qdisc_sleeping; 1559 } 1560 } else { 1561 q = rtnl_dereference(dev->qdisc); 1562 } 1563 1564 /* It may be default qdisc, ignore it */ 1565 if (q && q->handle == 0) 1566 q = NULL; 1567 1568 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1569 if (tcm->tcm_handle) { 1570 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) { 1571 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override"); 1572 return -EEXIST; 1573 } 1574 if (TC_H_MIN(tcm->tcm_handle)) { 1575 NL_SET_ERR_MSG(extack, "Invalid minor handle"); 1576 return -EINVAL; 1577 } 1578 q = qdisc_lookup(dev, tcm->tcm_handle); 1579 if (!q) 1580 goto create_n_graft; 1581 if (n->nlmsg_flags & NLM_F_EXCL) { 1582 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override"); 1583 return -EEXIST; 1584 } 1585 if (tca[TCA_KIND] && 1586 nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1587 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1588 return -EINVAL; 1589 } 1590 if (q == p || 1591 (p && check_loop(q, p, 0))) { 1592 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected"); 1593 return -ELOOP; 1594 } 1595 qdisc_refcount_inc(q); 1596 goto graft; 1597 } else { 1598 if (!q) 1599 goto create_n_graft; 1600 1601 /* This magic test requires explanation. 1602 * 1603 * We know, that some child q is already 1604 * attached to this parent and have choice: 1605 * either to change it or to create/graft new one. 1606 * 1607 * 1. We are allowed to create/graft only 1608 * if CREATE and REPLACE flags are set. 1609 * 1610 * 2. If EXCL is set, requestor wanted to say, 1611 * that qdisc tcm_handle is not expected 1612 * to exist, so that we choose create/graft too. 1613 * 1614 * 3. The last case is when no flags are set. 1615 * Alas, it is sort of hole in API, we 1616 * cannot decide what to do unambiguously. 1617 * For now we select create/graft, if 1618 * user gave KIND, which does not match existing. 1619 */ 1620 if ((n->nlmsg_flags & NLM_F_CREATE) && 1621 (n->nlmsg_flags & NLM_F_REPLACE) && 1622 ((n->nlmsg_flags & NLM_F_EXCL) || 1623 (tca[TCA_KIND] && 1624 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1625 goto create_n_graft; 1626 } 1627 } 1628 } else { 1629 if (!tcm->tcm_handle) { 1630 NL_SET_ERR_MSG(extack, "Handle cannot be zero"); 1631 return -EINVAL; 1632 } 1633 q = qdisc_lookup(dev, tcm->tcm_handle); 1634 } 1635 1636 /* Change qdisc parameters */ 1637 if (!q) { 1638 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1639 return -ENOENT; 1640 } 1641 if (n->nlmsg_flags & NLM_F_EXCL) { 1642 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify"); 1643 return -EEXIST; 1644 } 1645 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1646 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1647 return -EINVAL; 1648 } 1649 err = qdisc_change(q, tca, extack); 1650 if (err == 0) 1651 qdisc_notify(net, skb, n, clid, NULL, q); 1652 return err; 1653 1654 create_n_graft: 1655 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 1656 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag"); 1657 return -ENOENT; 1658 } 1659 if (clid == TC_H_INGRESS) { 1660 if (dev_ingress_queue(dev)) { 1661 q = qdisc_create(dev, dev_ingress_queue(dev), 1662 tcm->tcm_parent, tcm->tcm_parent, 1663 tca, &err, extack); 1664 } else { 1665 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device"); 1666 err = -ENOENT; 1667 } 1668 } else { 1669 struct netdev_queue *dev_queue; 1670 1671 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1672 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1673 else if (p) 1674 dev_queue = p->dev_queue; 1675 else 1676 dev_queue = netdev_get_tx_queue(dev, 0); 1677 1678 q = qdisc_create(dev, dev_queue, 1679 tcm->tcm_parent, tcm->tcm_handle, 1680 tca, &err, extack); 1681 } 1682 if (q == NULL) { 1683 if (err == -EAGAIN) 1684 goto replay; 1685 return err; 1686 } 1687 1688 graft: 1689 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack); 1690 if (err) { 1691 if (q) 1692 qdisc_put(q); 1693 return err; 1694 } 1695 1696 return 0; 1697 } 1698 1699 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1700 struct netlink_callback *cb, 1701 int *q_idx_p, int s_q_idx, bool recur, 1702 bool dump_invisible) 1703 { 1704 int ret = 0, q_idx = *q_idx_p; 1705 struct Qdisc *q; 1706 int b; 1707 1708 if (!root) 1709 return 0; 1710 1711 q = root; 1712 if (q_idx < s_q_idx) { 1713 q_idx++; 1714 } else { 1715 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1716 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1717 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1718 RTM_NEWQDISC) <= 0) 1719 goto done; 1720 q_idx++; 1721 } 1722 1723 /* If dumping singletons, there is no qdisc_dev(root) and the singleton 1724 * itself has already been dumped. 1725 * 1726 * If we've already dumped the top-level (ingress) qdisc above and the global 1727 * qdisc hashtable, we don't want to hit it again 1728 */ 1729 if (!qdisc_dev(root) || !recur) 1730 goto out; 1731 1732 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 1733 if (q_idx < s_q_idx) { 1734 q_idx++; 1735 continue; 1736 } 1737 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1738 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1739 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1740 RTM_NEWQDISC) <= 0) 1741 goto done; 1742 q_idx++; 1743 } 1744 1745 out: 1746 *q_idx_p = q_idx; 1747 return ret; 1748 done: 1749 ret = -1; 1750 goto out; 1751 } 1752 1753 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1754 { 1755 struct net *net = sock_net(skb->sk); 1756 int idx, q_idx; 1757 int s_idx, s_q_idx; 1758 struct net_device *dev; 1759 const struct nlmsghdr *nlh = cb->nlh; 1760 struct nlattr *tca[TCA_MAX + 1]; 1761 int err; 1762 1763 s_idx = cb->args[0]; 1764 s_q_idx = q_idx = cb->args[1]; 1765 1766 idx = 0; 1767 ASSERT_RTNL(); 1768 1769 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX, 1770 rtm_tca_policy, cb->extack); 1771 if (err < 0) 1772 return err; 1773 1774 for_each_netdev(net, dev) { 1775 struct netdev_queue *dev_queue; 1776 1777 if (idx < s_idx) 1778 goto cont; 1779 if (idx > s_idx) 1780 s_q_idx = 0; 1781 q_idx = 0; 1782 1783 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc), 1784 skb, cb, &q_idx, s_q_idx, 1785 true, tca[TCA_DUMP_INVISIBLE]) < 0) 1786 goto done; 1787 1788 dev_queue = dev_ingress_queue(dev); 1789 if (dev_queue && 1790 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1791 &q_idx, s_q_idx, false, 1792 tca[TCA_DUMP_INVISIBLE]) < 0) 1793 goto done; 1794 1795 cont: 1796 idx++; 1797 } 1798 1799 done: 1800 cb->args[0] = idx; 1801 cb->args[1] = q_idx; 1802 1803 return skb->len; 1804 } 1805 1806 1807 1808 /************************************************ 1809 * Traffic classes manipulation. * 1810 ************************************************/ 1811 1812 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1813 unsigned long cl, 1814 u32 portid, u32 seq, u16 flags, int event) 1815 { 1816 struct tcmsg *tcm; 1817 struct nlmsghdr *nlh; 1818 unsigned char *b = skb_tail_pointer(skb); 1819 struct gnet_dump d; 1820 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1821 1822 cond_resched(); 1823 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1824 if (!nlh) 1825 goto out_nlmsg_trim; 1826 tcm = nlmsg_data(nlh); 1827 tcm->tcm_family = AF_UNSPEC; 1828 tcm->tcm__pad1 = 0; 1829 tcm->tcm__pad2 = 0; 1830 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1831 tcm->tcm_parent = q->handle; 1832 tcm->tcm_handle = q->handle; 1833 tcm->tcm_info = 0; 1834 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1835 goto nla_put_failure; 1836 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1837 goto nla_put_failure; 1838 1839 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1840 NULL, &d, TCA_PAD) < 0) 1841 goto nla_put_failure; 1842 1843 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1844 goto nla_put_failure; 1845 1846 if (gnet_stats_finish_copy(&d) < 0) 1847 goto nla_put_failure; 1848 1849 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1850 return skb->len; 1851 1852 out_nlmsg_trim: 1853 nla_put_failure: 1854 nlmsg_trim(skb, b); 1855 return -1; 1856 } 1857 1858 static int tclass_notify(struct net *net, struct sk_buff *oskb, 1859 struct nlmsghdr *n, struct Qdisc *q, 1860 unsigned long cl, int event) 1861 { 1862 struct sk_buff *skb; 1863 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1864 1865 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1866 if (!skb) 1867 return -ENOBUFS; 1868 1869 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event) < 0) { 1870 kfree_skb(skb); 1871 return -EINVAL; 1872 } 1873 1874 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1875 n->nlmsg_flags & NLM_F_ECHO); 1876 } 1877 1878 static int tclass_del_notify(struct net *net, 1879 const struct Qdisc_class_ops *cops, 1880 struct sk_buff *oskb, struct nlmsghdr *n, 1881 struct Qdisc *q, unsigned long cl, 1882 struct netlink_ext_ack *extack) 1883 { 1884 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1885 struct sk_buff *skb; 1886 int err = 0; 1887 1888 if (!cops->delete) 1889 return -EOPNOTSUPP; 1890 1891 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1892 if (!skb) 1893 return -ENOBUFS; 1894 1895 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, 1896 RTM_DELTCLASS) < 0) { 1897 kfree_skb(skb); 1898 return -EINVAL; 1899 } 1900 1901 err = cops->delete(q, cl, extack); 1902 if (err) { 1903 kfree_skb(skb); 1904 return err; 1905 } 1906 1907 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1908 n->nlmsg_flags & NLM_F_ECHO); 1909 return err; 1910 } 1911 1912 #ifdef CONFIG_NET_CLS 1913 1914 struct tcf_bind_args { 1915 struct tcf_walker w; 1916 unsigned long base; 1917 unsigned long cl; 1918 u32 classid; 1919 }; 1920 1921 static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 1922 { 1923 struct tcf_bind_args *a = (void *)arg; 1924 1925 if (n && tp->ops->bind_class) { 1926 struct Qdisc *q = tcf_block_q(tp->chain->block); 1927 1928 sch_tree_lock(q); 1929 tp->ops->bind_class(n, a->classid, a->cl, q, a->base); 1930 sch_tree_unlock(q); 1931 } 1932 return 0; 1933 } 1934 1935 struct tc_bind_class_args { 1936 struct qdisc_walker w; 1937 unsigned long new_cl; 1938 u32 portid; 1939 u32 clid; 1940 }; 1941 1942 static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl, 1943 struct qdisc_walker *w) 1944 { 1945 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w; 1946 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1947 struct tcf_block *block; 1948 struct tcf_chain *chain; 1949 1950 block = cops->tcf_block(q, cl, NULL); 1951 if (!block) 1952 return 0; 1953 for (chain = tcf_get_next_chain(block, NULL); 1954 chain; 1955 chain = tcf_get_next_chain(block, chain)) { 1956 struct tcf_proto *tp; 1957 1958 for (tp = tcf_get_next_proto(chain, NULL); 1959 tp; tp = tcf_get_next_proto(chain, tp)) { 1960 struct tcf_bind_args arg = {}; 1961 1962 arg.w.fn = tcf_node_bind; 1963 arg.classid = a->clid; 1964 arg.base = cl; 1965 arg.cl = a->new_cl; 1966 tp->ops->walk(tp, &arg.w, true); 1967 } 1968 } 1969 1970 return 0; 1971 } 1972 1973 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1974 unsigned long new_cl) 1975 { 1976 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1977 struct tc_bind_class_args args = {}; 1978 1979 if (!cops->tcf_block) 1980 return; 1981 args.portid = portid; 1982 args.clid = clid; 1983 args.new_cl = new_cl; 1984 args.w.fn = tc_bind_class_walker; 1985 q->ops->cl_ops->walk(q, &args.w); 1986 } 1987 1988 #else 1989 1990 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1991 unsigned long new_cl) 1992 { 1993 } 1994 1995 #endif 1996 1997 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 1998 struct netlink_ext_ack *extack) 1999 { 2000 struct net *net = sock_net(skb->sk); 2001 struct tcmsg *tcm = nlmsg_data(n); 2002 struct nlattr *tca[TCA_MAX + 1]; 2003 struct net_device *dev; 2004 struct Qdisc *q = NULL; 2005 const struct Qdisc_class_ops *cops; 2006 unsigned long cl = 0; 2007 unsigned long new_cl; 2008 u32 portid; 2009 u32 clid; 2010 u32 qid; 2011 int err; 2012 2013 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 2014 rtm_tca_policy, extack); 2015 if (err < 0) 2016 return err; 2017 2018 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2019 if (!dev) 2020 return -ENODEV; 2021 2022 /* 2023 parent == TC_H_UNSPEC - unspecified parent. 2024 parent == TC_H_ROOT - class is root, which has no parent. 2025 parent == X:0 - parent is root class. 2026 parent == X:Y - parent is a node in hierarchy. 2027 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 2028 2029 handle == 0:0 - generate handle from kernel pool. 2030 handle == 0:Y - class is X:Y, where X:0 is qdisc. 2031 handle == X:Y - clear. 2032 handle == X:0 - root class. 2033 */ 2034 2035 /* Step 1. Determine qdisc handle X:0 */ 2036 2037 portid = tcm->tcm_parent; 2038 clid = tcm->tcm_handle; 2039 qid = TC_H_MAJ(clid); 2040 2041 if (portid != TC_H_ROOT) { 2042 u32 qid1 = TC_H_MAJ(portid); 2043 2044 if (qid && qid1) { 2045 /* If both majors are known, they must be identical. */ 2046 if (qid != qid1) 2047 return -EINVAL; 2048 } else if (qid1) { 2049 qid = qid1; 2050 } else if (qid == 0) 2051 qid = rtnl_dereference(dev->qdisc)->handle; 2052 2053 /* Now qid is genuine qdisc handle consistent 2054 * both with parent and child. 2055 * 2056 * TC_H_MAJ(portid) still may be unspecified, complete it now. 2057 */ 2058 if (portid) 2059 portid = TC_H_MAKE(qid, portid); 2060 } else { 2061 if (qid == 0) 2062 qid = rtnl_dereference(dev->qdisc)->handle; 2063 } 2064 2065 /* OK. Locate qdisc */ 2066 q = qdisc_lookup(dev, qid); 2067 if (!q) 2068 return -ENOENT; 2069 2070 /* An check that it supports classes */ 2071 cops = q->ops->cl_ops; 2072 if (cops == NULL) 2073 return -EINVAL; 2074 2075 /* Now try to get class */ 2076 if (clid == 0) { 2077 if (portid == TC_H_ROOT) 2078 clid = qid; 2079 } else 2080 clid = TC_H_MAKE(qid, clid); 2081 2082 if (clid) 2083 cl = cops->find(q, clid); 2084 2085 if (cl == 0) { 2086 err = -ENOENT; 2087 if (n->nlmsg_type != RTM_NEWTCLASS || 2088 !(n->nlmsg_flags & NLM_F_CREATE)) 2089 goto out; 2090 } else { 2091 switch (n->nlmsg_type) { 2092 case RTM_NEWTCLASS: 2093 err = -EEXIST; 2094 if (n->nlmsg_flags & NLM_F_EXCL) 2095 goto out; 2096 break; 2097 case RTM_DELTCLASS: 2098 err = tclass_del_notify(net, cops, skb, n, q, cl, extack); 2099 /* Unbind the class with flilters with 0 */ 2100 tc_bind_tclass(q, portid, clid, 0); 2101 goto out; 2102 case RTM_GETTCLASS: 2103 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS); 2104 goto out; 2105 default: 2106 err = -EINVAL; 2107 goto out; 2108 } 2109 } 2110 2111 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 2112 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes"); 2113 return -EOPNOTSUPP; 2114 } 2115 2116 new_cl = cl; 2117 err = -EOPNOTSUPP; 2118 if (cops->change) 2119 err = cops->change(q, clid, portid, tca, &new_cl, extack); 2120 if (err == 0) { 2121 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS); 2122 /* We just create a new class, need to do reverse binding. */ 2123 if (cl != new_cl) 2124 tc_bind_tclass(q, portid, clid, new_cl); 2125 } 2126 out: 2127 return err; 2128 } 2129 2130 struct qdisc_dump_args { 2131 struct qdisc_walker w; 2132 struct sk_buff *skb; 2133 struct netlink_callback *cb; 2134 }; 2135 2136 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, 2137 struct qdisc_walker *arg) 2138 { 2139 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 2140 2141 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 2142 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2143 RTM_NEWTCLASS); 2144 } 2145 2146 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 2147 struct tcmsg *tcm, struct netlink_callback *cb, 2148 int *t_p, int s_t) 2149 { 2150 struct qdisc_dump_args arg; 2151 2152 if (tc_qdisc_dump_ignore(q, false) || 2153 *t_p < s_t || !q->ops->cl_ops || 2154 (tcm->tcm_parent && 2155 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 2156 (*t_p)++; 2157 return 0; 2158 } 2159 if (*t_p > s_t) 2160 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 2161 arg.w.fn = qdisc_class_dump; 2162 arg.skb = skb; 2163 arg.cb = cb; 2164 arg.w.stop = 0; 2165 arg.w.skip = cb->args[1]; 2166 arg.w.count = 0; 2167 q->ops->cl_ops->walk(q, &arg.w); 2168 cb->args[1] = arg.w.count; 2169 if (arg.w.stop) 2170 return -1; 2171 (*t_p)++; 2172 return 0; 2173 } 2174 2175 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 2176 struct tcmsg *tcm, struct netlink_callback *cb, 2177 int *t_p, int s_t, bool recur) 2178 { 2179 struct Qdisc *q; 2180 int b; 2181 2182 if (!root) 2183 return 0; 2184 2185 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 2186 return -1; 2187 2188 if (!qdisc_dev(root) || !recur) 2189 return 0; 2190 2191 if (tcm->tcm_parent) { 2192 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent)); 2193 if (q && q != root && 2194 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2195 return -1; 2196 return 0; 2197 } 2198 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 2199 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2200 return -1; 2201 } 2202 2203 return 0; 2204 } 2205 2206 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 2207 { 2208 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2209 struct net *net = sock_net(skb->sk); 2210 struct netdev_queue *dev_queue; 2211 struct net_device *dev; 2212 int t, s_t; 2213 2214 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2215 return 0; 2216 dev = dev_get_by_index(net, tcm->tcm_ifindex); 2217 if (!dev) 2218 return 0; 2219 2220 s_t = cb->args[0]; 2221 t = 0; 2222 2223 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc), 2224 skb, tcm, cb, &t, s_t, true) < 0) 2225 goto done; 2226 2227 dev_queue = dev_ingress_queue(dev); 2228 if (dev_queue && 2229 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 2230 &t, s_t, false) < 0) 2231 goto done; 2232 2233 done: 2234 cb->args[0] = t; 2235 2236 dev_put(dev); 2237 return skb->len; 2238 } 2239 2240 #ifdef CONFIG_PROC_FS 2241 static int psched_show(struct seq_file *seq, void *v) 2242 { 2243 seq_printf(seq, "%08x %08x %08x %08x\n", 2244 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 2245 1000000, 2246 (u32)NSEC_PER_SEC / hrtimer_resolution); 2247 2248 return 0; 2249 } 2250 2251 static int __net_init psched_net_init(struct net *net) 2252 { 2253 struct proc_dir_entry *e; 2254 2255 e = proc_create_single("psched", 0, net->proc_net, psched_show); 2256 if (e == NULL) 2257 return -ENOMEM; 2258 2259 return 0; 2260 } 2261 2262 static void __net_exit psched_net_exit(struct net *net) 2263 { 2264 remove_proc_entry("psched", net->proc_net); 2265 } 2266 #else 2267 static int __net_init psched_net_init(struct net *net) 2268 { 2269 return 0; 2270 } 2271 2272 static void __net_exit psched_net_exit(struct net *net) 2273 { 2274 } 2275 #endif 2276 2277 static struct pernet_operations psched_net_ops = { 2278 .init = psched_net_init, 2279 .exit = psched_net_exit, 2280 }; 2281 2282 DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper); 2283 2284 static int __init pktsched_init(void) 2285 { 2286 int err; 2287 2288 err = register_pernet_subsys(&psched_net_ops); 2289 if (err) { 2290 pr_err("pktsched_init: " 2291 "cannot initialize per netns operations\n"); 2292 return err; 2293 } 2294 2295 register_qdisc(&pfifo_fast_ops); 2296 register_qdisc(&pfifo_qdisc_ops); 2297 register_qdisc(&bfifo_qdisc_ops); 2298 register_qdisc(&pfifo_head_drop_qdisc_ops); 2299 register_qdisc(&mq_qdisc_ops); 2300 register_qdisc(&noqueue_qdisc_ops); 2301 2302 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0); 2303 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0); 2304 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, 2305 0); 2306 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0); 2307 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0); 2308 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, 2309 0); 2310 2311 tc_wrapper_init(); 2312 2313 return 0; 2314 } 2315 2316 subsys_initcall(pktsched_init); 2317