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 struct netlink_ext_ack *extack) 907 { 908 struct gnet_stats_basic_sync __percpu *cpu_bstats = NULL; 909 struct gnet_stats_queue __percpu *cpu_qstats = NULL; 910 struct tcmsg *tcm; 911 struct nlmsghdr *nlh; 912 unsigned char *b = skb_tail_pointer(skb); 913 struct gnet_dump d; 914 struct qdisc_size_table *stab; 915 u32 block_index; 916 __u32 qlen; 917 918 cond_resched(); 919 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 920 if (!nlh) 921 goto out_nlmsg_trim; 922 tcm = nlmsg_data(nlh); 923 tcm->tcm_family = AF_UNSPEC; 924 tcm->tcm__pad1 = 0; 925 tcm->tcm__pad2 = 0; 926 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 927 tcm->tcm_parent = clid; 928 tcm->tcm_handle = q->handle; 929 tcm->tcm_info = refcount_read(&q->refcnt); 930 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 931 goto nla_put_failure; 932 if (q->ops->ingress_block_get) { 933 block_index = q->ops->ingress_block_get(q); 934 if (block_index && 935 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index)) 936 goto nla_put_failure; 937 } 938 if (q->ops->egress_block_get) { 939 block_index = q->ops->egress_block_get(q); 940 if (block_index && 941 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index)) 942 goto nla_put_failure; 943 } 944 if (q->ops->dump && q->ops->dump(q, skb) < 0) 945 goto nla_put_failure; 946 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED))) 947 goto nla_put_failure; 948 qlen = qdisc_qlen_sum(q); 949 950 stab = rtnl_dereference(q->stab); 951 if (stab && qdisc_dump_stab(skb, stab) < 0) 952 goto nla_put_failure; 953 954 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 955 NULL, &d, TCA_PAD) < 0) 956 goto nla_put_failure; 957 958 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 959 goto nla_put_failure; 960 961 if (qdisc_is_percpu_stats(q)) { 962 cpu_bstats = q->cpu_bstats; 963 cpu_qstats = q->cpu_qstats; 964 } 965 966 if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats, true) < 0 || 967 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 968 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0) 969 goto nla_put_failure; 970 971 if (gnet_stats_finish_copy(&d) < 0) 972 goto nla_put_failure; 973 974 if (extack && extack->_msg && 975 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg)) 976 goto out_nlmsg_trim; 977 978 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 979 980 return skb->len; 981 982 out_nlmsg_trim: 983 nla_put_failure: 984 nlmsg_trim(skb, b); 985 return -1; 986 } 987 988 static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible) 989 { 990 if (q->flags & TCQ_F_BUILTIN) 991 return true; 992 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible) 993 return true; 994 995 return false; 996 } 997 998 static int qdisc_notify(struct net *net, struct sk_buff *oskb, 999 struct nlmsghdr *n, u32 clid, 1000 struct Qdisc *old, struct Qdisc *new, 1001 struct netlink_ext_ack *extack) 1002 { 1003 struct sk_buff *skb; 1004 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1005 1006 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1007 if (!skb) 1008 return -ENOBUFS; 1009 1010 if (old && !tc_qdisc_dump_ignore(old, false)) { 1011 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq, 1012 0, RTM_DELQDISC, extack) < 0) 1013 goto err_out; 1014 } 1015 if (new && !tc_qdisc_dump_ignore(new, false)) { 1016 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq, 1017 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC, extack) < 0) 1018 goto err_out; 1019 } 1020 1021 if (skb->len) 1022 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1023 n->nlmsg_flags & NLM_F_ECHO); 1024 1025 err_out: 1026 kfree_skb(skb); 1027 return -EINVAL; 1028 } 1029 1030 static void notify_and_destroy(struct net *net, struct sk_buff *skb, 1031 struct nlmsghdr *n, u32 clid, 1032 struct Qdisc *old, struct Qdisc *new, 1033 struct netlink_ext_ack *extack) 1034 { 1035 if (new || old) 1036 qdisc_notify(net, skb, n, clid, old, new, extack); 1037 1038 if (old) 1039 qdisc_put(old); 1040 } 1041 1042 static void qdisc_clear_nolock(struct Qdisc *sch) 1043 { 1044 sch->flags &= ~TCQ_F_NOLOCK; 1045 if (!(sch->flags & TCQ_F_CPUSTATS)) 1046 return; 1047 1048 free_percpu(sch->cpu_bstats); 1049 free_percpu(sch->cpu_qstats); 1050 sch->cpu_bstats = NULL; 1051 sch->cpu_qstats = NULL; 1052 sch->flags &= ~TCQ_F_CPUSTATS; 1053 } 1054 1055 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 1056 * to device "dev". 1057 * 1058 * When appropriate send a netlink notification using 'skb' 1059 * and "n". 1060 * 1061 * On success, destroy old qdisc. 1062 */ 1063 1064 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 1065 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 1066 struct Qdisc *new, struct Qdisc *old, 1067 struct netlink_ext_ack *extack) 1068 { 1069 struct Qdisc *q = old; 1070 struct net *net = dev_net(dev); 1071 1072 if (parent == NULL) { 1073 unsigned int i, num_q, ingress; 1074 1075 ingress = 0; 1076 num_q = dev->num_tx_queues; 1077 if ((q && q->flags & TCQ_F_INGRESS) || 1078 (new && new->flags & TCQ_F_INGRESS)) { 1079 num_q = 1; 1080 ingress = 1; 1081 if (!dev_ingress_queue(dev)) { 1082 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue"); 1083 return -ENOENT; 1084 } 1085 } 1086 1087 if (dev->flags & IFF_UP) 1088 dev_deactivate(dev); 1089 1090 qdisc_offload_graft_root(dev, new, old, extack); 1091 1092 if (new && new->ops->attach && !ingress) 1093 goto skip; 1094 1095 for (i = 0; i < num_q; i++) { 1096 struct netdev_queue *dev_queue = dev_ingress_queue(dev); 1097 1098 if (!ingress) 1099 dev_queue = netdev_get_tx_queue(dev, i); 1100 1101 old = dev_graft_qdisc(dev_queue, new); 1102 if (new && i > 0) 1103 qdisc_refcount_inc(new); 1104 1105 if (!ingress) 1106 qdisc_put(old); 1107 } 1108 1109 skip: 1110 if (!ingress) { 1111 old = rtnl_dereference(dev->qdisc); 1112 if (new && !new->ops->attach) 1113 qdisc_refcount_inc(new); 1114 rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc); 1115 1116 notify_and_destroy(net, skb, n, classid, old, new, extack); 1117 1118 if (new && new->ops->attach) 1119 new->ops->attach(new); 1120 } else { 1121 notify_and_destroy(net, skb, n, classid, old, new, extack); 1122 } 1123 1124 if (dev->flags & IFF_UP) 1125 dev_activate(dev); 1126 } else { 1127 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 1128 unsigned long cl; 1129 int err; 1130 1131 /* Only support running class lockless if parent is lockless */ 1132 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK)) 1133 qdisc_clear_nolock(new); 1134 1135 if (!cops || !cops->graft) 1136 return -EOPNOTSUPP; 1137 1138 cl = cops->find(parent, classid); 1139 if (!cl) { 1140 NL_SET_ERR_MSG(extack, "Specified class not found"); 1141 return -ENOENT; 1142 } 1143 1144 if (new && new->ops == &noqueue_qdisc_ops) { 1145 NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class"); 1146 return -EINVAL; 1147 } 1148 1149 err = cops->graft(parent, cl, new, &old, extack); 1150 if (err) 1151 return err; 1152 notify_and_destroy(net, skb, n, classid, old, new, extack); 1153 } 1154 return 0; 1155 } 1156 1157 static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca, 1158 struct netlink_ext_ack *extack) 1159 { 1160 u32 block_index; 1161 1162 if (tca[TCA_INGRESS_BLOCK]) { 1163 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]); 1164 1165 if (!block_index) { 1166 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0"); 1167 return -EINVAL; 1168 } 1169 if (!sch->ops->ingress_block_set) { 1170 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported"); 1171 return -EOPNOTSUPP; 1172 } 1173 sch->ops->ingress_block_set(sch, block_index); 1174 } 1175 if (tca[TCA_EGRESS_BLOCK]) { 1176 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]); 1177 1178 if (!block_index) { 1179 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0"); 1180 return -EINVAL; 1181 } 1182 if (!sch->ops->egress_block_set) { 1183 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported"); 1184 return -EOPNOTSUPP; 1185 } 1186 sch->ops->egress_block_set(sch, block_index); 1187 } 1188 return 0; 1189 } 1190 1191 /* 1192 Allocate and initialize new qdisc. 1193 1194 Parameters are passed via opt. 1195 */ 1196 1197 static struct Qdisc *qdisc_create(struct net_device *dev, 1198 struct netdev_queue *dev_queue, 1199 u32 parent, u32 handle, 1200 struct nlattr **tca, int *errp, 1201 struct netlink_ext_ack *extack) 1202 { 1203 int err; 1204 struct nlattr *kind = tca[TCA_KIND]; 1205 struct Qdisc *sch; 1206 struct Qdisc_ops *ops; 1207 struct qdisc_size_table *stab; 1208 1209 ops = qdisc_lookup_ops(kind); 1210 #ifdef CONFIG_MODULES 1211 if (ops == NULL && kind != NULL) { 1212 char name[IFNAMSIZ]; 1213 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) { 1214 /* We dropped the RTNL semaphore in order to 1215 * perform the module load. So, even if we 1216 * succeeded in loading the module we have to 1217 * tell the caller to replay the request. We 1218 * indicate this using -EAGAIN. 1219 * We replay the request because the device may 1220 * go away in the mean time. 1221 */ 1222 rtnl_unlock(); 1223 request_module("sch_%s", name); 1224 rtnl_lock(); 1225 ops = qdisc_lookup_ops(kind); 1226 if (ops != NULL) { 1227 /* We will try again qdisc_lookup_ops, 1228 * so don't keep a reference. 1229 */ 1230 module_put(ops->owner); 1231 err = -EAGAIN; 1232 goto err_out; 1233 } 1234 } 1235 } 1236 #endif 1237 1238 err = -ENOENT; 1239 if (!ops) { 1240 NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown"); 1241 goto err_out; 1242 } 1243 1244 sch = qdisc_alloc(dev_queue, ops, extack); 1245 if (IS_ERR(sch)) { 1246 err = PTR_ERR(sch); 1247 goto err_out2; 1248 } 1249 1250 sch->parent = parent; 1251 1252 if (handle == TC_H_INGRESS) { 1253 sch->flags |= TCQ_F_INGRESS; 1254 handle = TC_H_MAKE(TC_H_INGRESS, 0); 1255 } else { 1256 if (handle == 0) { 1257 handle = qdisc_alloc_handle(dev); 1258 if (handle == 0) { 1259 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded"); 1260 err = -ENOSPC; 1261 goto err_out3; 1262 } 1263 } 1264 if (!netif_is_multiqueue(dev)) 1265 sch->flags |= TCQ_F_ONETXQUEUE; 1266 } 1267 1268 sch->handle = handle; 1269 1270 /* This exist to keep backward compatible with a userspace 1271 * loophole, what allowed userspace to get IFF_NO_QUEUE 1272 * facility on older kernels by setting tx_queue_len=0 (prior 1273 * to qdisc init), and then forgot to reinit tx_queue_len 1274 * before again attaching a qdisc. 1275 */ 1276 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) { 1277 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 1278 netdev_info(dev, "Caught tx_queue_len zero misconfig\n"); 1279 } 1280 1281 err = qdisc_block_indexes_set(sch, tca, extack); 1282 if (err) 1283 goto err_out3; 1284 1285 if (tca[TCA_STAB]) { 1286 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1287 if (IS_ERR(stab)) { 1288 err = PTR_ERR(stab); 1289 goto err_out4; 1290 } 1291 rcu_assign_pointer(sch->stab, stab); 1292 } 1293 1294 if (ops->init) { 1295 err = ops->init(sch, tca[TCA_OPTIONS], extack); 1296 if (err != 0) 1297 goto err_out5; 1298 } 1299 1300 if (tca[TCA_RATE]) { 1301 err = -EOPNOTSUPP; 1302 if (sch->flags & TCQ_F_MQROOT) { 1303 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc"); 1304 goto err_out5; 1305 } 1306 1307 err = gen_new_estimator(&sch->bstats, 1308 sch->cpu_bstats, 1309 &sch->rate_est, 1310 NULL, 1311 true, 1312 tca[TCA_RATE]); 1313 if (err) { 1314 NL_SET_ERR_MSG(extack, "Failed to generate new estimator"); 1315 goto err_out5; 1316 } 1317 } 1318 1319 qdisc_hash_add(sch, false); 1320 trace_qdisc_create(ops, dev, parent); 1321 1322 return sch; 1323 1324 err_out5: 1325 qdisc_put_stab(rtnl_dereference(sch->stab)); 1326 err_out4: 1327 /* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */ 1328 if (ops->destroy) 1329 ops->destroy(sch); 1330 err_out3: 1331 netdev_put(dev, &sch->dev_tracker); 1332 qdisc_free(sch); 1333 err_out2: 1334 module_put(ops->owner); 1335 err_out: 1336 *errp = err; 1337 return NULL; 1338 } 1339 1340 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca, 1341 struct netlink_ext_ack *extack) 1342 { 1343 struct qdisc_size_table *ostab, *stab = NULL; 1344 int err = 0; 1345 1346 if (tca[TCA_OPTIONS]) { 1347 if (!sch->ops->change) { 1348 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc"); 1349 return -EINVAL; 1350 } 1351 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 1352 NL_SET_ERR_MSG(extack, "Change of blocks is not supported"); 1353 return -EOPNOTSUPP; 1354 } 1355 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack); 1356 if (err) 1357 return err; 1358 } 1359 1360 if (tca[TCA_STAB]) { 1361 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1362 if (IS_ERR(stab)) 1363 return PTR_ERR(stab); 1364 } 1365 1366 ostab = rtnl_dereference(sch->stab); 1367 rcu_assign_pointer(sch->stab, stab); 1368 qdisc_put_stab(ostab); 1369 1370 if (tca[TCA_RATE]) { 1371 /* NB: ignores errors from replace_estimator 1372 because change can't be undone. */ 1373 if (sch->flags & TCQ_F_MQROOT) 1374 goto out; 1375 gen_replace_estimator(&sch->bstats, 1376 sch->cpu_bstats, 1377 &sch->rate_est, 1378 NULL, 1379 true, 1380 tca[TCA_RATE]); 1381 } 1382 out: 1383 return 0; 1384 } 1385 1386 struct check_loop_arg { 1387 struct qdisc_walker w; 1388 struct Qdisc *p; 1389 int depth; 1390 }; 1391 1392 static int check_loop_fn(struct Qdisc *q, unsigned long cl, 1393 struct qdisc_walker *w); 1394 1395 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 1396 { 1397 struct check_loop_arg arg; 1398 1399 if (q->ops->cl_ops == NULL) 1400 return 0; 1401 1402 arg.w.stop = arg.w.skip = arg.w.count = 0; 1403 arg.w.fn = check_loop_fn; 1404 arg.depth = depth; 1405 arg.p = p; 1406 q->ops->cl_ops->walk(q, &arg.w); 1407 return arg.w.stop ? -ELOOP : 0; 1408 } 1409 1410 static int 1411 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 1412 { 1413 struct Qdisc *leaf; 1414 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1415 struct check_loop_arg *arg = (struct check_loop_arg *)w; 1416 1417 leaf = cops->leaf(q, cl); 1418 if (leaf) { 1419 if (leaf == arg->p || arg->depth > 7) 1420 return -ELOOP; 1421 return check_loop(leaf, arg->p, arg->depth + 1); 1422 } 1423 return 0; 1424 } 1425 1426 const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = { 1427 [TCA_KIND] = { .type = NLA_STRING }, 1428 [TCA_RATE] = { .type = NLA_BINARY, 1429 .len = sizeof(struct tc_estimator) }, 1430 [TCA_STAB] = { .type = NLA_NESTED }, 1431 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG }, 1432 [TCA_CHAIN] = { .type = NLA_U32 }, 1433 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 }, 1434 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 }, 1435 }; 1436 1437 /* 1438 * Delete/get qdisc. 1439 */ 1440 1441 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1442 struct netlink_ext_ack *extack) 1443 { 1444 struct net *net = sock_net(skb->sk); 1445 struct tcmsg *tcm = nlmsg_data(n); 1446 struct nlattr *tca[TCA_MAX + 1]; 1447 struct net_device *dev; 1448 u32 clid; 1449 struct Qdisc *q = NULL; 1450 struct Qdisc *p = NULL; 1451 int err; 1452 1453 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1454 rtm_tca_policy, extack); 1455 if (err < 0) 1456 return err; 1457 1458 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1459 if (!dev) 1460 return -ENODEV; 1461 1462 clid = tcm->tcm_parent; 1463 if (clid) { 1464 if (clid != TC_H_ROOT) { 1465 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1466 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1467 if (!p) { 1468 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid"); 1469 return -ENOENT; 1470 } 1471 q = qdisc_leaf(p, clid); 1472 } else if (dev_ingress_queue(dev)) { 1473 q = dev_ingress_queue(dev)->qdisc_sleeping; 1474 } 1475 } else { 1476 q = rtnl_dereference(dev->qdisc); 1477 } 1478 if (!q) { 1479 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); 1480 return -ENOENT; 1481 } 1482 1483 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) { 1484 NL_SET_ERR_MSG(extack, "Invalid handle"); 1485 return -EINVAL; 1486 } 1487 } else { 1488 q = qdisc_lookup(dev, tcm->tcm_handle); 1489 if (!q) { 1490 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle"); 1491 return -ENOENT; 1492 } 1493 } 1494 1495 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1496 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1497 return -EINVAL; 1498 } 1499 1500 if (n->nlmsg_type == RTM_DELQDISC) { 1501 if (!clid) { 1502 NL_SET_ERR_MSG(extack, "Classid cannot be zero"); 1503 return -EINVAL; 1504 } 1505 if (q->handle == 0) { 1506 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero"); 1507 return -ENOENT; 1508 } 1509 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack); 1510 if (err != 0) 1511 return err; 1512 } else { 1513 qdisc_notify(net, skb, n, clid, NULL, q, NULL); 1514 } 1515 return 0; 1516 } 1517 1518 /* 1519 * Create/change qdisc. 1520 */ 1521 1522 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1523 struct netlink_ext_ack *extack) 1524 { 1525 struct net *net = sock_net(skb->sk); 1526 struct tcmsg *tcm; 1527 struct nlattr *tca[TCA_MAX + 1]; 1528 struct net_device *dev; 1529 u32 clid; 1530 struct Qdisc *q, *p; 1531 int err; 1532 1533 replay: 1534 /* Reinit, just in case something touches this. */ 1535 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1536 rtm_tca_policy, extack); 1537 if (err < 0) 1538 return err; 1539 1540 tcm = nlmsg_data(n); 1541 clid = tcm->tcm_parent; 1542 q = p = NULL; 1543 1544 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1545 if (!dev) 1546 return -ENODEV; 1547 1548 1549 if (clid) { 1550 if (clid != TC_H_ROOT) { 1551 if (clid != TC_H_INGRESS) { 1552 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1553 if (!p) { 1554 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); 1555 return -ENOENT; 1556 } 1557 q = qdisc_leaf(p, clid); 1558 } else if (dev_ingress_queue_create(dev)) { 1559 q = dev_ingress_queue(dev)->qdisc_sleeping; 1560 } 1561 } else { 1562 q = rtnl_dereference(dev->qdisc); 1563 } 1564 1565 /* It may be default qdisc, ignore it */ 1566 if (q && q->handle == 0) 1567 q = NULL; 1568 1569 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1570 if (tcm->tcm_handle) { 1571 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) { 1572 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override"); 1573 return -EEXIST; 1574 } 1575 if (TC_H_MIN(tcm->tcm_handle)) { 1576 NL_SET_ERR_MSG(extack, "Invalid minor handle"); 1577 return -EINVAL; 1578 } 1579 q = qdisc_lookup(dev, tcm->tcm_handle); 1580 if (!q) 1581 goto create_n_graft; 1582 if (n->nlmsg_flags & NLM_F_EXCL) { 1583 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override"); 1584 return -EEXIST; 1585 } 1586 if (tca[TCA_KIND] && 1587 nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1588 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1589 return -EINVAL; 1590 } 1591 if (q == p || 1592 (p && check_loop(q, p, 0))) { 1593 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected"); 1594 return -ELOOP; 1595 } 1596 qdisc_refcount_inc(q); 1597 goto graft; 1598 } else { 1599 if (!q) 1600 goto create_n_graft; 1601 1602 /* This magic test requires explanation. 1603 * 1604 * We know, that some child q is already 1605 * attached to this parent and have choice: 1606 * either to change it or to create/graft new one. 1607 * 1608 * 1. We are allowed to create/graft only 1609 * if CREATE and REPLACE flags are set. 1610 * 1611 * 2. If EXCL is set, requestor wanted to say, 1612 * that qdisc tcm_handle is not expected 1613 * to exist, so that we choose create/graft too. 1614 * 1615 * 3. The last case is when no flags are set. 1616 * Alas, it is sort of hole in API, we 1617 * cannot decide what to do unambiguously. 1618 * For now we select create/graft, if 1619 * user gave KIND, which does not match existing. 1620 */ 1621 if ((n->nlmsg_flags & NLM_F_CREATE) && 1622 (n->nlmsg_flags & NLM_F_REPLACE) && 1623 ((n->nlmsg_flags & NLM_F_EXCL) || 1624 (tca[TCA_KIND] && 1625 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1626 goto create_n_graft; 1627 } 1628 } 1629 } else { 1630 if (!tcm->tcm_handle) { 1631 NL_SET_ERR_MSG(extack, "Handle cannot be zero"); 1632 return -EINVAL; 1633 } 1634 q = qdisc_lookup(dev, tcm->tcm_handle); 1635 } 1636 1637 /* Change qdisc parameters */ 1638 if (!q) { 1639 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1640 return -ENOENT; 1641 } 1642 if (n->nlmsg_flags & NLM_F_EXCL) { 1643 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify"); 1644 return -EEXIST; 1645 } 1646 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1647 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1648 return -EINVAL; 1649 } 1650 err = qdisc_change(q, tca, extack); 1651 if (err == 0) 1652 qdisc_notify(net, skb, n, clid, NULL, q, extack); 1653 return err; 1654 1655 create_n_graft: 1656 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 1657 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag"); 1658 return -ENOENT; 1659 } 1660 if (clid == TC_H_INGRESS) { 1661 if (dev_ingress_queue(dev)) { 1662 q = qdisc_create(dev, dev_ingress_queue(dev), 1663 tcm->tcm_parent, tcm->tcm_parent, 1664 tca, &err, extack); 1665 } else { 1666 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device"); 1667 err = -ENOENT; 1668 } 1669 } else { 1670 struct netdev_queue *dev_queue; 1671 1672 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1673 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1674 else if (p) 1675 dev_queue = p->dev_queue; 1676 else 1677 dev_queue = netdev_get_tx_queue(dev, 0); 1678 1679 q = qdisc_create(dev, dev_queue, 1680 tcm->tcm_parent, tcm->tcm_handle, 1681 tca, &err, extack); 1682 } 1683 if (q == NULL) { 1684 if (err == -EAGAIN) 1685 goto replay; 1686 return err; 1687 } 1688 1689 graft: 1690 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack); 1691 if (err) { 1692 if (q) 1693 qdisc_put(q); 1694 return err; 1695 } 1696 1697 return 0; 1698 } 1699 1700 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1701 struct netlink_callback *cb, 1702 int *q_idx_p, int s_q_idx, bool recur, 1703 bool dump_invisible) 1704 { 1705 int ret = 0, q_idx = *q_idx_p; 1706 struct Qdisc *q; 1707 int b; 1708 1709 if (!root) 1710 return 0; 1711 1712 q = root; 1713 if (q_idx < s_q_idx) { 1714 q_idx++; 1715 } else { 1716 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1717 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1718 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1719 RTM_NEWQDISC, NULL) <= 0) 1720 goto done; 1721 q_idx++; 1722 } 1723 1724 /* If dumping singletons, there is no qdisc_dev(root) and the singleton 1725 * itself has already been dumped. 1726 * 1727 * If we've already dumped the top-level (ingress) qdisc above and the global 1728 * qdisc hashtable, we don't want to hit it again 1729 */ 1730 if (!qdisc_dev(root) || !recur) 1731 goto out; 1732 1733 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 1734 if (q_idx < s_q_idx) { 1735 q_idx++; 1736 continue; 1737 } 1738 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1739 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1740 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1741 RTM_NEWQDISC, NULL) <= 0) 1742 goto done; 1743 q_idx++; 1744 } 1745 1746 out: 1747 *q_idx_p = q_idx; 1748 return ret; 1749 done: 1750 ret = -1; 1751 goto out; 1752 } 1753 1754 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1755 { 1756 struct net *net = sock_net(skb->sk); 1757 int idx, q_idx; 1758 int s_idx, s_q_idx; 1759 struct net_device *dev; 1760 const struct nlmsghdr *nlh = cb->nlh; 1761 struct nlattr *tca[TCA_MAX + 1]; 1762 int err; 1763 1764 s_idx = cb->args[0]; 1765 s_q_idx = q_idx = cb->args[1]; 1766 1767 idx = 0; 1768 ASSERT_RTNL(); 1769 1770 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX, 1771 rtm_tca_policy, cb->extack); 1772 if (err < 0) 1773 return err; 1774 1775 for_each_netdev(net, dev) { 1776 struct netdev_queue *dev_queue; 1777 1778 if (idx < s_idx) 1779 goto cont; 1780 if (idx > s_idx) 1781 s_q_idx = 0; 1782 q_idx = 0; 1783 1784 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc), 1785 skb, cb, &q_idx, s_q_idx, 1786 true, tca[TCA_DUMP_INVISIBLE]) < 0) 1787 goto done; 1788 1789 dev_queue = dev_ingress_queue(dev); 1790 if (dev_queue && 1791 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1792 &q_idx, s_q_idx, false, 1793 tca[TCA_DUMP_INVISIBLE]) < 0) 1794 goto done; 1795 1796 cont: 1797 idx++; 1798 } 1799 1800 done: 1801 cb->args[0] = idx; 1802 cb->args[1] = q_idx; 1803 1804 return skb->len; 1805 } 1806 1807 1808 1809 /************************************************ 1810 * Traffic classes manipulation. * 1811 ************************************************/ 1812 1813 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1814 unsigned long cl, u32 portid, u32 seq, u16 flags, 1815 int event, struct netlink_ext_ack *extack) 1816 { 1817 struct tcmsg *tcm; 1818 struct nlmsghdr *nlh; 1819 unsigned char *b = skb_tail_pointer(skb); 1820 struct gnet_dump d; 1821 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1822 1823 cond_resched(); 1824 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1825 if (!nlh) 1826 goto out_nlmsg_trim; 1827 tcm = nlmsg_data(nlh); 1828 tcm->tcm_family = AF_UNSPEC; 1829 tcm->tcm__pad1 = 0; 1830 tcm->tcm__pad2 = 0; 1831 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1832 tcm->tcm_parent = q->handle; 1833 tcm->tcm_handle = q->handle; 1834 tcm->tcm_info = 0; 1835 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1836 goto nla_put_failure; 1837 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1838 goto nla_put_failure; 1839 1840 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1841 NULL, &d, TCA_PAD) < 0) 1842 goto nla_put_failure; 1843 1844 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1845 goto nla_put_failure; 1846 1847 if (gnet_stats_finish_copy(&d) < 0) 1848 goto nla_put_failure; 1849 1850 if (extack && extack->_msg && 1851 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg)) 1852 goto out_nlmsg_trim; 1853 1854 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1855 1856 return skb->len; 1857 1858 out_nlmsg_trim: 1859 nla_put_failure: 1860 nlmsg_trim(skb, b); 1861 return -1; 1862 } 1863 1864 static int tclass_notify(struct net *net, struct sk_buff *oskb, 1865 struct nlmsghdr *n, struct Qdisc *q, 1866 unsigned long cl, int event, struct netlink_ext_ack *extack) 1867 { 1868 struct sk_buff *skb; 1869 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1870 1871 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1872 if (!skb) 1873 return -ENOBUFS; 1874 1875 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event, extack) < 0) { 1876 kfree_skb(skb); 1877 return -EINVAL; 1878 } 1879 1880 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1881 n->nlmsg_flags & NLM_F_ECHO); 1882 } 1883 1884 static int tclass_del_notify(struct net *net, 1885 const struct Qdisc_class_ops *cops, 1886 struct sk_buff *oskb, struct nlmsghdr *n, 1887 struct Qdisc *q, unsigned long cl, 1888 struct netlink_ext_ack *extack) 1889 { 1890 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1891 struct sk_buff *skb; 1892 int err = 0; 1893 1894 if (!cops->delete) 1895 return -EOPNOTSUPP; 1896 1897 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1898 if (!skb) 1899 return -ENOBUFS; 1900 1901 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, 1902 RTM_DELTCLASS, extack) < 0) { 1903 kfree_skb(skb); 1904 return -EINVAL; 1905 } 1906 1907 err = cops->delete(q, cl, extack); 1908 if (err) { 1909 kfree_skb(skb); 1910 return err; 1911 } 1912 1913 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1914 n->nlmsg_flags & NLM_F_ECHO); 1915 return err; 1916 } 1917 1918 #ifdef CONFIG_NET_CLS 1919 1920 struct tcf_bind_args { 1921 struct tcf_walker w; 1922 unsigned long base; 1923 unsigned long cl; 1924 u32 classid; 1925 }; 1926 1927 static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 1928 { 1929 struct tcf_bind_args *a = (void *)arg; 1930 1931 if (n && tp->ops->bind_class) { 1932 struct Qdisc *q = tcf_block_q(tp->chain->block); 1933 1934 sch_tree_lock(q); 1935 tp->ops->bind_class(n, a->classid, a->cl, q, a->base); 1936 sch_tree_unlock(q); 1937 } 1938 return 0; 1939 } 1940 1941 struct tc_bind_class_args { 1942 struct qdisc_walker w; 1943 unsigned long new_cl; 1944 u32 portid; 1945 u32 clid; 1946 }; 1947 1948 static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl, 1949 struct qdisc_walker *w) 1950 { 1951 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w; 1952 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1953 struct tcf_block *block; 1954 struct tcf_chain *chain; 1955 1956 block = cops->tcf_block(q, cl, NULL); 1957 if (!block) 1958 return 0; 1959 for (chain = tcf_get_next_chain(block, NULL); 1960 chain; 1961 chain = tcf_get_next_chain(block, chain)) { 1962 struct tcf_proto *tp; 1963 1964 for (tp = tcf_get_next_proto(chain, NULL); 1965 tp; tp = tcf_get_next_proto(chain, tp)) { 1966 struct tcf_bind_args arg = {}; 1967 1968 arg.w.fn = tcf_node_bind; 1969 arg.classid = a->clid; 1970 arg.base = cl; 1971 arg.cl = a->new_cl; 1972 tp->ops->walk(tp, &arg.w, true); 1973 } 1974 } 1975 1976 return 0; 1977 } 1978 1979 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1980 unsigned long new_cl) 1981 { 1982 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1983 struct tc_bind_class_args args = {}; 1984 1985 if (!cops->tcf_block) 1986 return; 1987 args.portid = portid; 1988 args.clid = clid; 1989 args.new_cl = new_cl; 1990 args.w.fn = tc_bind_class_walker; 1991 q->ops->cl_ops->walk(q, &args.w); 1992 } 1993 1994 #else 1995 1996 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1997 unsigned long new_cl) 1998 { 1999 } 2000 2001 #endif 2002 2003 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 2004 struct netlink_ext_ack *extack) 2005 { 2006 struct net *net = sock_net(skb->sk); 2007 struct tcmsg *tcm = nlmsg_data(n); 2008 struct nlattr *tca[TCA_MAX + 1]; 2009 struct net_device *dev; 2010 struct Qdisc *q = NULL; 2011 const struct Qdisc_class_ops *cops; 2012 unsigned long cl = 0; 2013 unsigned long new_cl; 2014 u32 portid; 2015 u32 clid; 2016 u32 qid; 2017 int err; 2018 2019 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 2020 rtm_tca_policy, extack); 2021 if (err < 0) 2022 return err; 2023 2024 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2025 if (!dev) 2026 return -ENODEV; 2027 2028 /* 2029 parent == TC_H_UNSPEC - unspecified parent. 2030 parent == TC_H_ROOT - class is root, which has no parent. 2031 parent == X:0 - parent is root class. 2032 parent == X:Y - parent is a node in hierarchy. 2033 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 2034 2035 handle == 0:0 - generate handle from kernel pool. 2036 handle == 0:Y - class is X:Y, where X:0 is qdisc. 2037 handle == X:Y - clear. 2038 handle == X:0 - root class. 2039 */ 2040 2041 /* Step 1. Determine qdisc handle X:0 */ 2042 2043 portid = tcm->tcm_parent; 2044 clid = tcm->tcm_handle; 2045 qid = TC_H_MAJ(clid); 2046 2047 if (portid != TC_H_ROOT) { 2048 u32 qid1 = TC_H_MAJ(portid); 2049 2050 if (qid && qid1) { 2051 /* If both majors are known, they must be identical. */ 2052 if (qid != qid1) 2053 return -EINVAL; 2054 } else if (qid1) { 2055 qid = qid1; 2056 } else if (qid == 0) 2057 qid = rtnl_dereference(dev->qdisc)->handle; 2058 2059 /* Now qid is genuine qdisc handle consistent 2060 * both with parent and child. 2061 * 2062 * TC_H_MAJ(portid) still may be unspecified, complete it now. 2063 */ 2064 if (portid) 2065 portid = TC_H_MAKE(qid, portid); 2066 } else { 2067 if (qid == 0) 2068 qid = rtnl_dereference(dev->qdisc)->handle; 2069 } 2070 2071 /* OK. Locate qdisc */ 2072 q = qdisc_lookup(dev, qid); 2073 if (!q) 2074 return -ENOENT; 2075 2076 /* An check that it supports classes */ 2077 cops = q->ops->cl_ops; 2078 if (cops == NULL) 2079 return -EINVAL; 2080 2081 /* Now try to get class */ 2082 if (clid == 0) { 2083 if (portid == TC_H_ROOT) 2084 clid = qid; 2085 } else 2086 clid = TC_H_MAKE(qid, clid); 2087 2088 if (clid) 2089 cl = cops->find(q, clid); 2090 2091 if (cl == 0) { 2092 err = -ENOENT; 2093 if (n->nlmsg_type != RTM_NEWTCLASS || 2094 !(n->nlmsg_flags & NLM_F_CREATE)) 2095 goto out; 2096 } else { 2097 switch (n->nlmsg_type) { 2098 case RTM_NEWTCLASS: 2099 err = -EEXIST; 2100 if (n->nlmsg_flags & NLM_F_EXCL) 2101 goto out; 2102 break; 2103 case RTM_DELTCLASS: 2104 err = tclass_del_notify(net, cops, skb, n, q, cl, extack); 2105 /* Unbind the class with flilters with 0 */ 2106 tc_bind_tclass(q, portid, clid, 0); 2107 goto out; 2108 case RTM_GETTCLASS: 2109 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS, extack); 2110 goto out; 2111 default: 2112 err = -EINVAL; 2113 goto out; 2114 } 2115 } 2116 2117 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 2118 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes"); 2119 return -EOPNOTSUPP; 2120 } 2121 2122 new_cl = cl; 2123 err = -EOPNOTSUPP; 2124 if (cops->change) 2125 err = cops->change(q, clid, portid, tca, &new_cl, extack); 2126 if (err == 0) { 2127 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack); 2128 /* We just create a new class, need to do reverse binding. */ 2129 if (cl != new_cl) 2130 tc_bind_tclass(q, portid, clid, new_cl); 2131 } 2132 out: 2133 return err; 2134 } 2135 2136 struct qdisc_dump_args { 2137 struct qdisc_walker w; 2138 struct sk_buff *skb; 2139 struct netlink_callback *cb; 2140 }; 2141 2142 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, 2143 struct qdisc_walker *arg) 2144 { 2145 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 2146 2147 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 2148 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2149 RTM_NEWTCLASS, NULL); 2150 } 2151 2152 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 2153 struct tcmsg *tcm, struct netlink_callback *cb, 2154 int *t_p, int s_t) 2155 { 2156 struct qdisc_dump_args arg; 2157 2158 if (tc_qdisc_dump_ignore(q, false) || 2159 *t_p < s_t || !q->ops->cl_ops || 2160 (tcm->tcm_parent && 2161 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 2162 (*t_p)++; 2163 return 0; 2164 } 2165 if (*t_p > s_t) 2166 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 2167 arg.w.fn = qdisc_class_dump; 2168 arg.skb = skb; 2169 arg.cb = cb; 2170 arg.w.stop = 0; 2171 arg.w.skip = cb->args[1]; 2172 arg.w.count = 0; 2173 q->ops->cl_ops->walk(q, &arg.w); 2174 cb->args[1] = arg.w.count; 2175 if (arg.w.stop) 2176 return -1; 2177 (*t_p)++; 2178 return 0; 2179 } 2180 2181 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 2182 struct tcmsg *tcm, struct netlink_callback *cb, 2183 int *t_p, int s_t, bool recur) 2184 { 2185 struct Qdisc *q; 2186 int b; 2187 2188 if (!root) 2189 return 0; 2190 2191 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 2192 return -1; 2193 2194 if (!qdisc_dev(root) || !recur) 2195 return 0; 2196 2197 if (tcm->tcm_parent) { 2198 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent)); 2199 if (q && q != root && 2200 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2201 return -1; 2202 return 0; 2203 } 2204 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 2205 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2206 return -1; 2207 } 2208 2209 return 0; 2210 } 2211 2212 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 2213 { 2214 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2215 struct net *net = sock_net(skb->sk); 2216 struct netdev_queue *dev_queue; 2217 struct net_device *dev; 2218 int t, s_t; 2219 2220 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2221 return 0; 2222 dev = dev_get_by_index(net, tcm->tcm_ifindex); 2223 if (!dev) 2224 return 0; 2225 2226 s_t = cb->args[0]; 2227 t = 0; 2228 2229 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc), 2230 skb, tcm, cb, &t, s_t, true) < 0) 2231 goto done; 2232 2233 dev_queue = dev_ingress_queue(dev); 2234 if (dev_queue && 2235 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 2236 &t, s_t, false) < 0) 2237 goto done; 2238 2239 done: 2240 cb->args[0] = t; 2241 2242 dev_put(dev); 2243 return skb->len; 2244 } 2245 2246 #ifdef CONFIG_PROC_FS 2247 static int psched_show(struct seq_file *seq, void *v) 2248 { 2249 seq_printf(seq, "%08x %08x %08x %08x\n", 2250 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 2251 1000000, 2252 (u32)NSEC_PER_SEC / hrtimer_resolution); 2253 2254 return 0; 2255 } 2256 2257 static int __net_init psched_net_init(struct net *net) 2258 { 2259 struct proc_dir_entry *e; 2260 2261 e = proc_create_single("psched", 0, net->proc_net, psched_show); 2262 if (e == NULL) 2263 return -ENOMEM; 2264 2265 return 0; 2266 } 2267 2268 static void __net_exit psched_net_exit(struct net *net) 2269 { 2270 remove_proc_entry("psched", net->proc_net); 2271 } 2272 #else 2273 static int __net_init psched_net_init(struct net *net) 2274 { 2275 return 0; 2276 } 2277 2278 static void __net_exit psched_net_exit(struct net *net) 2279 { 2280 } 2281 #endif 2282 2283 static struct pernet_operations psched_net_ops = { 2284 .init = psched_net_init, 2285 .exit = psched_net_exit, 2286 }; 2287 2288 DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper); 2289 2290 static int __init pktsched_init(void) 2291 { 2292 int err; 2293 2294 err = register_pernet_subsys(&psched_net_ops); 2295 if (err) { 2296 pr_err("pktsched_init: " 2297 "cannot initialize per netns operations\n"); 2298 return err; 2299 } 2300 2301 register_qdisc(&pfifo_fast_ops); 2302 register_qdisc(&pfifo_qdisc_ops); 2303 register_qdisc(&bfifo_qdisc_ops); 2304 register_qdisc(&pfifo_head_drop_qdisc_ops); 2305 register_qdisc(&mq_qdisc_ops); 2306 register_qdisc(&noqueue_qdisc_ops); 2307 2308 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0); 2309 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0); 2310 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, 2311 0); 2312 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0); 2313 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0); 2314 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, 2315 0); 2316 2317 tc_wrapper_init(); 2318 2319 return 0; 2320 } 2321 2322 subsys_initcall(pktsched_init); 2323