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 u64 softexpires; 643 644 softexpires = ktime_to_ns(hrtimer_get_softexpires(&wd->timer)); 645 /* If timer is already set in [expires, expires + delta_ns], 646 * do not reprogram it. 647 */ 648 if (softexpires - expires <= delta_ns) 649 return; 650 } 651 652 hrtimer_start_range_ns(&wd->timer, 653 ns_to_ktime(expires), 654 delta_ns, 655 HRTIMER_MODE_ABS_PINNED); 656 } 657 EXPORT_SYMBOL(qdisc_watchdog_schedule_range_ns); 658 659 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 660 { 661 hrtimer_cancel(&wd->timer); 662 } 663 EXPORT_SYMBOL(qdisc_watchdog_cancel); 664 665 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 666 { 667 struct hlist_head *h; 668 unsigned int i; 669 670 h = kvmalloc_array(n, sizeof(struct hlist_head), GFP_KERNEL); 671 672 if (h != NULL) { 673 for (i = 0; i < n; i++) 674 INIT_HLIST_HEAD(&h[i]); 675 } 676 return h; 677 } 678 679 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 680 { 681 struct Qdisc_class_common *cl; 682 struct hlist_node *next; 683 struct hlist_head *nhash, *ohash; 684 unsigned int nsize, nmask, osize; 685 unsigned int i, h; 686 687 /* Rehash when load factor exceeds 0.75 */ 688 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 689 return; 690 nsize = clhash->hashsize * 2; 691 nmask = nsize - 1; 692 nhash = qdisc_class_hash_alloc(nsize); 693 if (nhash == NULL) 694 return; 695 696 ohash = clhash->hash; 697 osize = clhash->hashsize; 698 699 sch_tree_lock(sch); 700 for (i = 0; i < osize; i++) { 701 hlist_for_each_entry_safe(cl, next, &ohash[i], hnode) { 702 h = qdisc_class_hash(cl->classid, nmask); 703 hlist_add_head(&cl->hnode, &nhash[h]); 704 } 705 } 706 clhash->hash = nhash; 707 clhash->hashsize = nsize; 708 clhash->hashmask = nmask; 709 sch_tree_unlock(sch); 710 711 kvfree(ohash); 712 } 713 EXPORT_SYMBOL(qdisc_class_hash_grow); 714 715 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 716 { 717 unsigned int size = 4; 718 719 clhash->hash = qdisc_class_hash_alloc(size); 720 if (!clhash->hash) 721 return -ENOMEM; 722 clhash->hashsize = size; 723 clhash->hashmask = size - 1; 724 clhash->hashelems = 0; 725 return 0; 726 } 727 EXPORT_SYMBOL(qdisc_class_hash_init); 728 729 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 730 { 731 kvfree(clhash->hash); 732 } 733 EXPORT_SYMBOL(qdisc_class_hash_destroy); 734 735 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 736 struct Qdisc_class_common *cl) 737 { 738 unsigned int h; 739 740 INIT_HLIST_NODE(&cl->hnode); 741 h = qdisc_class_hash(cl->classid, clhash->hashmask); 742 hlist_add_head(&cl->hnode, &clhash->hash[h]); 743 clhash->hashelems++; 744 } 745 EXPORT_SYMBOL(qdisc_class_hash_insert); 746 747 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 748 struct Qdisc_class_common *cl) 749 { 750 hlist_del(&cl->hnode); 751 clhash->hashelems--; 752 } 753 EXPORT_SYMBOL(qdisc_class_hash_remove); 754 755 /* Allocate an unique handle from space managed by kernel 756 * Possible range is [8000-FFFF]:0000 (0x8000 values) 757 */ 758 static u32 qdisc_alloc_handle(struct net_device *dev) 759 { 760 int i = 0x8000; 761 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 762 763 do { 764 autohandle += TC_H_MAKE(0x10000U, 0); 765 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 766 autohandle = TC_H_MAKE(0x80000000U, 0); 767 if (!qdisc_lookup(dev, autohandle)) 768 return autohandle; 769 cond_resched(); 770 } while (--i > 0); 771 772 return 0; 773 } 774 775 void qdisc_tree_reduce_backlog(struct Qdisc *sch, int n, int len) 776 { 777 bool qdisc_is_offloaded = sch->flags & TCQ_F_OFFLOADED; 778 const struct Qdisc_class_ops *cops; 779 unsigned long cl; 780 u32 parentid; 781 bool notify; 782 int drops; 783 784 if (n == 0 && len == 0) 785 return; 786 drops = max_t(int, n, 0); 787 rcu_read_lock(); 788 while ((parentid = sch->parent)) { 789 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 790 break; 791 792 if (sch->flags & TCQ_F_NOPARENT) 793 break; 794 /* Notify parent qdisc only if child qdisc becomes empty. 795 * 796 * If child was empty even before update then backlog 797 * counter is screwed and we skip notification because 798 * parent class is already passive. 799 * 800 * If the original child was offloaded then it is allowed 801 * to be seem as empty, so the parent is notified anyway. 802 */ 803 notify = !sch->q.qlen && !WARN_ON_ONCE(!n && 804 !qdisc_is_offloaded); 805 /* TODO: perform the search on a per txq basis */ 806 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 807 if (sch == NULL) { 808 WARN_ON_ONCE(parentid != TC_H_ROOT); 809 break; 810 } 811 cops = sch->ops->cl_ops; 812 if (notify && cops->qlen_notify) { 813 cl = cops->find(sch, parentid); 814 cops->qlen_notify(sch, cl); 815 } 816 sch->q.qlen -= n; 817 sch->qstats.backlog -= len; 818 __qdisc_qstats_drop(sch, drops); 819 } 820 rcu_read_unlock(); 821 } 822 EXPORT_SYMBOL(qdisc_tree_reduce_backlog); 823 824 int qdisc_offload_dump_helper(struct Qdisc *sch, enum tc_setup_type type, 825 void *type_data) 826 { 827 struct net_device *dev = qdisc_dev(sch); 828 int err; 829 830 sch->flags &= ~TCQ_F_OFFLOADED; 831 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 832 return 0; 833 834 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 835 if (err == -EOPNOTSUPP) 836 return 0; 837 838 if (!err) 839 sch->flags |= TCQ_F_OFFLOADED; 840 841 return err; 842 } 843 EXPORT_SYMBOL(qdisc_offload_dump_helper); 844 845 void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch, 846 struct Qdisc *new, struct Qdisc *old, 847 enum tc_setup_type type, void *type_data, 848 struct netlink_ext_ack *extack) 849 { 850 bool any_qdisc_is_offloaded; 851 int err; 852 853 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) 854 return; 855 856 err = dev->netdev_ops->ndo_setup_tc(dev, type, type_data); 857 858 /* Don't report error if the graft is part of destroy operation. */ 859 if (!err || !new || new == &noop_qdisc) 860 return; 861 862 /* Don't report error if the parent, the old child and the new 863 * one are not offloaded. 864 */ 865 any_qdisc_is_offloaded = new->flags & TCQ_F_OFFLOADED; 866 any_qdisc_is_offloaded |= sch && sch->flags & TCQ_F_OFFLOADED; 867 any_qdisc_is_offloaded |= old && old->flags & TCQ_F_OFFLOADED; 868 869 if (any_qdisc_is_offloaded) 870 NL_SET_ERR_MSG(extack, "Offloading graft operation failed."); 871 } 872 EXPORT_SYMBOL(qdisc_offload_graft_helper); 873 874 void qdisc_offload_query_caps(struct net_device *dev, 875 enum tc_setup_type type, 876 void *caps, size_t caps_len) 877 { 878 const struct net_device_ops *ops = dev->netdev_ops; 879 struct tc_query_caps_base base = { 880 .type = type, 881 .caps = caps, 882 }; 883 884 memset(caps, 0, caps_len); 885 886 if (ops->ndo_setup_tc) 887 ops->ndo_setup_tc(dev, TC_QUERY_CAPS, &base); 888 } 889 EXPORT_SYMBOL(qdisc_offload_query_caps); 890 891 static void qdisc_offload_graft_root(struct net_device *dev, 892 struct Qdisc *new, struct Qdisc *old, 893 struct netlink_ext_ack *extack) 894 { 895 struct tc_root_qopt_offload graft_offload = { 896 .command = TC_ROOT_GRAFT, 897 .handle = new ? new->handle : 0, 898 .ingress = (new && new->flags & TCQ_F_INGRESS) || 899 (old && old->flags & TCQ_F_INGRESS), 900 }; 901 902 qdisc_offload_graft_helper(dev, NULL, new, old, 903 TC_SETUP_ROOT_QDISC, &graft_offload, extack); 904 } 905 906 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 907 u32 portid, u32 seq, u16 flags, int event, 908 struct netlink_ext_ack *extack) 909 { 910 struct gnet_stats_basic_sync __percpu *cpu_bstats = NULL; 911 struct gnet_stats_queue __percpu *cpu_qstats = NULL; 912 struct tcmsg *tcm; 913 struct nlmsghdr *nlh; 914 unsigned char *b = skb_tail_pointer(skb); 915 struct gnet_dump d; 916 struct qdisc_size_table *stab; 917 u32 block_index; 918 __u32 qlen; 919 920 cond_resched(); 921 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 922 if (!nlh) 923 goto out_nlmsg_trim; 924 tcm = nlmsg_data(nlh); 925 tcm->tcm_family = AF_UNSPEC; 926 tcm->tcm__pad1 = 0; 927 tcm->tcm__pad2 = 0; 928 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 929 tcm->tcm_parent = clid; 930 tcm->tcm_handle = q->handle; 931 tcm->tcm_info = refcount_read(&q->refcnt); 932 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 933 goto nla_put_failure; 934 if (q->ops->ingress_block_get) { 935 block_index = q->ops->ingress_block_get(q); 936 if (block_index && 937 nla_put_u32(skb, TCA_INGRESS_BLOCK, block_index)) 938 goto nla_put_failure; 939 } 940 if (q->ops->egress_block_get) { 941 block_index = q->ops->egress_block_get(q); 942 if (block_index && 943 nla_put_u32(skb, TCA_EGRESS_BLOCK, block_index)) 944 goto nla_put_failure; 945 } 946 if (q->ops->dump && q->ops->dump(q, skb) < 0) 947 goto nla_put_failure; 948 if (nla_put_u8(skb, TCA_HW_OFFLOAD, !!(q->flags & TCQ_F_OFFLOADED))) 949 goto nla_put_failure; 950 qlen = qdisc_qlen_sum(q); 951 952 stab = rtnl_dereference(q->stab); 953 if (stab && qdisc_dump_stab(skb, stab) < 0) 954 goto nla_put_failure; 955 956 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 957 NULL, &d, TCA_PAD) < 0) 958 goto nla_put_failure; 959 960 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 961 goto nla_put_failure; 962 963 if (qdisc_is_percpu_stats(q)) { 964 cpu_bstats = q->cpu_bstats; 965 cpu_qstats = q->cpu_qstats; 966 } 967 968 if (gnet_stats_copy_basic(&d, cpu_bstats, &q->bstats, true) < 0 || 969 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 970 gnet_stats_copy_queue(&d, cpu_qstats, &q->qstats, qlen) < 0) 971 goto nla_put_failure; 972 973 if (gnet_stats_finish_copy(&d) < 0) 974 goto nla_put_failure; 975 976 if (extack && extack->_msg && 977 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg)) 978 goto out_nlmsg_trim; 979 980 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 981 982 return skb->len; 983 984 out_nlmsg_trim: 985 nla_put_failure: 986 nlmsg_trim(skb, b); 987 return -1; 988 } 989 990 static bool tc_qdisc_dump_ignore(struct Qdisc *q, bool dump_invisible) 991 { 992 if (q->flags & TCQ_F_BUILTIN) 993 return true; 994 if ((q->flags & TCQ_F_INVISIBLE) && !dump_invisible) 995 return true; 996 997 return false; 998 } 999 1000 static int qdisc_notify(struct net *net, struct sk_buff *oskb, 1001 struct nlmsghdr *n, u32 clid, 1002 struct Qdisc *old, struct Qdisc *new, 1003 struct netlink_ext_ack *extack) 1004 { 1005 struct sk_buff *skb; 1006 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1007 1008 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1009 if (!skb) 1010 return -ENOBUFS; 1011 1012 if (old && !tc_qdisc_dump_ignore(old, false)) { 1013 if (tc_fill_qdisc(skb, old, clid, portid, n->nlmsg_seq, 1014 0, RTM_DELQDISC, extack) < 0) 1015 goto err_out; 1016 } 1017 if (new && !tc_qdisc_dump_ignore(new, false)) { 1018 if (tc_fill_qdisc(skb, new, clid, portid, n->nlmsg_seq, 1019 old ? NLM_F_REPLACE : 0, RTM_NEWQDISC, extack) < 0) 1020 goto err_out; 1021 } 1022 1023 if (skb->len) 1024 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1025 n->nlmsg_flags & NLM_F_ECHO); 1026 1027 err_out: 1028 kfree_skb(skb); 1029 return -EINVAL; 1030 } 1031 1032 static void notify_and_destroy(struct net *net, struct sk_buff *skb, 1033 struct nlmsghdr *n, u32 clid, 1034 struct Qdisc *old, struct Qdisc *new, 1035 struct netlink_ext_ack *extack) 1036 { 1037 if (new || old) 1038 qdisc_notify(net, skb, n, clid, old, new, extack); 1039 1040 if (old) 1041 qdisc_put(old); 1042 } 1043 1044 static void qdisc_clear_nolock(struct Qdisc *sch) 1045 { 1046 sch->flags &= ~TCQ_F_NOLOCK; 1047 if (!(sch->flags & TCQ_F_CPUSTATS)) 1048 return; 1049 1050 free_percpu(sch->cpu_bstats); 1051 free_percpu(sch->cpu_qstats); 1052 sch->cpu_bstats = NULL; 1053 sch->cpu_qstats = NULL; 1054 sch->flags &= ~TCQ_F_CPUSTATS; 1055 } 1056 1057 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 1058 * to device "dev". 1059 * 1060 * When appropriate send a netlink notification using 'skb' 1061 * and "n". 1062 * 1063 * On success, destroy old qdisc. 1064 */ 1065 1066 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 1067 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 1068 struct Qdisc *new, struct Qdisc *old, 1069 struct netlink_ext_ack *extack) 1070 { 1071 struct Qdisc *q = old; 1072 struct net *net = dev_net(dev); 1073 1074 if (parent == NULL) { 1075 unsigned int i, num_q, ingress; 1076 1077 ingress = 0; 1078 num_q = dev->num_tx_queues; 1079 if ((q && q->flags & TCQ_F_INGRESS) || 1080 (new && new->flags & TCQ_F_INGRESS)) { 1081 num_q = 1; 1082 ingress = 1; 1083 if (!dev_ingress_queue(dev)) { 1084 NL_SET_ERR_MSG(extack, "Device does not have an ingress queue"); 1085 return -ENOENT; 1086 } 1087 } 1088 1089 if (dev->flags & IFF_UP) 1090 dev_deactivate(dev); 1091 1092 qdisc_offload_graft_root(dev, new, old, extack); 1093 1094 if (new && new->ops->attach && !ingress) 1095 goto skip; 1096 1097 for (i = 0; i < num_q; i++) { 1098 struct netdev_queue *dev_queue = dev_ingress_queue(dev); 1099 1100 if (!ingress) 1101 dev_queue = netdev_get_tx_queue(dev, i); 1102 1103 old = dev_graft_qdisc(dev_queue, new); 1104 if (new && i > 0) 1105 qdisc_refcount_inc(new); 1106 1107 if (!ingress) 1108 qdisc_put(old); 1109 } 1110 1111 skip: 1112 if (!ingress) { 1113 old = rtnl_dereference(dev->qdisc); 1114 if (new && !new->ops->attach) 1115 qdisc_refcount_inc(new); 1116 rcu_assign_pointer(dev->qdisc, new ? : &noop_qdisc); 1117 1118 notify_and_destroy(net, skb, n, classid, old, new, extack); 1119 1120 if (new && new->ops->attach) 1121 new->ops->attach(new); 1122 } else { 1123 notify_and_destroy(net, skb, n, classid, old, new, extack); 1124 } 1125 1126 if (dev->flags & IFF_UP) 1127 dev_activate(dev); 1128 } else { 1129 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 1130 unsigned long cl; 1131 int err; 1132 1133 /* Only support running class lockless if parent is lockless */ 1134 if (new && (new->flags & TCQ_F_NOLOCK) && !(parent->flags & TCQ_F_NOLOCK)) 1135 qdisc_clear_nolock(new); 1136 1137 if (!cops || !cops->graft) 1138 return -EOPNOTSUPP; 1139 1140 cl = cops->find(parent, classid); 1141 if (!cl) { 1142 NL_SET_ERR_MSG(extack, "Specified class not found"); 1143 return -ENOENT; 1144 } 1145 1146 if (new && new->ops == &noqueue_qdisc_ops) { 1147 NL_SET_ERR_MSG(extack, "Cannot assign noqueue to a class"); 1148 return -EINVAL; 1149 } 1150 1151 err = cops->graft(parent, cl, new, &old, extack); 1152 if (err) 1153 return err; 1154 notify_and_destroy(net, skb, n, classid, old, new, extack); 1155 } 1156 return 0; 1157 } 1158 1159 static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca, 1160 struct netlink_ext_ack *extack) 1161 { 1162 u32 block_index; 1163 1164 if (tca[TCA_INGRESS_BLOCK]) { 1165 block_index = nla_get_u32(tca[TCA_INGRESS_BLOCK]); 1166 1167 if (!block_index) { 1168 NL_SET_ERR_MSG(extack, "Ingress block index cannot be 0"); 1169 return -EINVAL; 1170 } 1171 if (!sch->ops->ingress_block_set) { 1172 NL_SET_ERR_MSG(extack, "Ingress block sharing is not supported"); 1173 return -EOPNOTSUPP; 1174 } 1175 sch->ops->ingress_block_set(sch, block_index); 1176 } 1177 if (tca[TCA_EGRESS_BLOCK]) { 1178 block_index = nla_get_u32(tca[TCA_EGRESS_BLOCK]); 1179 1180 if (!block_index) { 1181 NL_SET_ERR_MSG(extack, "Egress block index cannot be 0"); 1182 return -EINVAL; 1183 } 1184 if (!sch->ops->egress_block_set) { 1185 NL_SET_ERR_MSG(extack, "Egress block sharing is not supported"); 1186 return -EOPNOTSUPP; 1187 } 1188 sch->ops->egress_block_set(sch, block_index); 1189 } 1190 return 0; 1191 } 1192 1193 /* 1194 Allocate and initialize new qdisc. 1195 1196 Parameters are passed via opt. 1197 */ 1198 1199 static struct Qdisc *qdisc_create(struct net_device *dev, 1200 struct netdev_queue *dev_queue, 1201 u32 parent, u32 handle, 1202 struct nlattr **tca, int *errp, 1203 struct netlink_ext_ack *extack) 1204 { 1205 int err; 1206 struct nlattr *kind = tca[TCA_KIND]; 1207 struct Qdisc *sch; 1208 struct Qdisc_ops *ops; 1209 struct qdisc_size_table *stab; 1210 1211 ops = qdisc_lookup_ops(kind); 1212 #ifdef CONFIG_MODULES 1213 if (ops == NULL && kind != NULL) { 1214 char name[IFNAMSIZ]; 1215 if (nla_strscpy(name, kind, IFNAMSIZ) >= 0) { 1216 /* We dropped the RTNL semaphore in order to 1217 * perform the module load. So, even if we 1218 * succeeded in loading the module we have to 1219 * tell the caller to replay the request. We 1220 * indicate this using -EAGAIN. 1221 * We replay the request because the device may 1222 * go away in the mean time. 1223 */ 1224 rtnl_unlock(); 1225 request_module("sch_%s", name); 1226 rtnl_lock(); 1227 ops = qdisc_lookup_ops(kind); 1228 if (ops != NULL) { 1229 /* We will try again qdisc_lookup_ops, 1230 * so don't keep a reference. 1231 */ 1232 module_put(ops->owner); 1233 err = -EAGAIN; 1234 goto err_out; 1235 } 1236 } 1237 } 1238 #endif 1239 1240 err = -ENOENT; 1241 if (!ops) { 1242 NL_SET_ERR_MSG(extack, "Specified qdisc kind is unknown"); 1243 goto err_out; 1244 } 1245 1246 sch = qdisc_alloc(dev_queue, ops, extack); 1247 if (IS_ERR(sch)) { 1248 err = PTR_ERR(sch); 1249 goto err_out2; 1250 } 1251 1252 sch->parent = parent; 1253 1254 if (handle == TC_H_INGRESS) { 1255 sch->flags |= TCQ_F_INGRESS; 1256 handle = TC_H_MAKE(TC_H_INGRESS, 0); 1257 } else { 1258 if (handle == 0) { 1259 handle = qdisc_alloc_handle(dev); 1260 if (handle == 0) { 1261 NL_SET_ERR_MSG(extack, "Maximum number of qdisc handles was exceeded"); 1262 err = -ENOSPC; 1263 goto err_out3; 1264 } 1265 } 1266 if (!netif_is_multiqueue(dev)) 1267 sch->flags |= TCQ_F_ONETXQUEUE; 1268 } 1269 1270 sch->handle = handle; 1271 1272 /* This exist to keep backward compatible with a userspace 1273 * loophole, what allowed userspace to get IFF_NO_QUEUE 1274 * facility on older kernels by setting tx_queue_len=0 (prior 1275 * to qdisc init), and then forgot to reinit tx_queue_len 1276 * before again attaching a qdisc. 1277 */ 1278 if ((dev->priv_flags & IFF_NO_QUEUE) && (dev->tx_queue_len == 0)) { 1279 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 1280 netdev_info(dev, "Caught tx_queue_len zero misconfig\n"); 1281 } 1282 1283 err = qdisc_block_indexes_set(sch, tca, extack); 1284 if (err) 1285 goto err_out3; 1286 1287 if (tca[TCA_STAB]) { 1288 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1289 if (IS_ERR(stab)) { 1290 err = PTR_ERR(stab); 1291 goto err_out3; 1292 } 1293 rcu_assign_pointer(sch->stab, stab); 1294 } 1295 1296 if (ops->init) { 1297 err = ops->init(sch, tca[TCA_OPTIONS], extack); 1298 if (err != 0) 1299 goto err_out4; 1300 } 1301 1302 if (tca[TCA_RATE]) { 1303 err = -EOPNOTSUPP; 1304 if (sch->flags & TCQ_F_MQROOT) { 1305 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc"); 1306 goto err_out4; 1307 } 1308 1309 err = gen_new_estimator(&sch->bstats, 1310 sch->cpu_bstats, 1311 &sch->rate_est, 1312 NULL, 1313 true, 1314 tca[TCA_RATE]); 1315 if (err) { 1316 NL_SET_ERR_MSG(extack, "Failed to generate new estimator"); 1317 goto err_out4; 1318 } 1319 } 1320 1321 qdisc_hash_add(sch, false); 1322 trace_qdisc_create(ops, dev, parent); 1323 1324 return sch; 1325 1326 err_out4: 1327 /* Even if ops->init() failed, we call ops->destroy() 1328 * like qdisc_create_dflt(). 1329 */ 1330 if (ops->destroy) 1331 ops->destroy(sch); 1332 qdisc_put_stab(rtnl_dereference(sch->stab)); 1333 err_out3: 1334 netdev_put(dev, &sch->dev_tracker); 1335 qdisc_free(sch); 1336 err_out2: 1337 module_put(ops->owner); 1338 err_out: 1339 *errp = err; 1340 return NULL; 1341 } 1342 1343 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca, 1344 struct netlink_ext_ack *extack) 1345 { 1346 struct qdisc_size_table *ostab, *stab = NULL; 1347 int err = 0; 1348 1349 if (tca[TCA_OPTIONS]) { 1350 if (!sch->ops->change) { 1351 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc"); 1352 return -EINVAL; 1353 } 1354 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 1355 NL_SET_ERR_MSG(extack, "Change of blocks is not supported"); 1356 return -EOPNOTSUPP; 1357 } 1358 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack); 1359 if (err) 1360 return err; 1361 } 1362 1363 if (tca[TCA_STAB]) { 1364 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1365 if (IS_ERR(stab)) 1366 return PTR_ERR(stab); 1367 } 1368 1369 ostab = rtnl_dereference(sch->stab); 1370 rcu_assign_pointer(sch->stab, stab); 1371 qdisc_put_stab(ostab); 1372 1373 if (tca[TCA_RATE]) { 1374 /* NB: ignores errors from replace_estimator 1375 because change can't be undone. */ 1376 if (sch->flags & TCQ_F_MQROOT) 1377 goto out; 1378 gen_replace_estimator(&sch->bstats, 1379 sch->cpu_bstats, 1380 &sch->rate_est, 1381 NULL, 1382 true, 1383 tca[TCA_RATE]); 1384 } 1385 out: 1386 return 0; 1387 } 1388 1389 struct check_loop_arg { 1390 struct qdisc_walker w; 1391 struct Qdisc *p; 1392 int depth; 1393 }; 1394 1395 static int check_loop_fn(struct Qdisc *q, unsigned long cl, 1396 struct qdisc_walker *w); 1397 1398 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 1399 { 1400 struct check_loop_arg arg; 1401 1402 if (q->ops->cl_ops == NULL) 1403 return 0; 1404 1405 arg.w.stop = arg.w.skip = arg.w.count = 0; 1406 arg.w.fn = check_loop_fn; 1407 arg.depth = depth; 1408 arg.p = p; 1409 q->ops->cl_ops->walk(q, &arg.w); 1410 return arg.w.stop ? -ELOOP : 0; 1411 } 1412 1413 static int 1414 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 1415 { 1416 struct Qdisc *leaf; 1417 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1418 struct check_loop_arg *arg = (struct check_loop_arg *)w; 1419 1420 leaf = cops->leaf(q, cl); 1421 if (leaf) { 1422 if (leaf == arg->p || arg->depth > 7) 1423 return -ELOOP; 1424 return check_loop(leaf, arg->p, arg->depth + 1); 1425 } 1426 return 0; 1427 } 1428 1429 const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = { 1430 [TCA_KIND] = { .type = NLA_STRING }, 1431 [TCA_RATE] = { .type = NLA_BINARY, 1432 .len = sizeof(struct tc_estimator) }, 1433 [TCA_STAB] = { .type = NLA_NESTED }, 1434 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG }, 1435 [TCA_CHAIN] = { .type = NLA_U32 }, 1436 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 }, 1437 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 }, 1438 }; 1439 1440 /* 1441 * Delete/get qdisc. 1442 */ 1443 1444 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1445 struct netlink_ext_ack *extack) 1446 { 1447 struct net *net = sock_net(skb->sk); 1448 struct tcmsg *tcm = nlmsg_data(n); 1449 struct nlattr *tca[TCA_MAX + 1]; 1450 struct net_device *dev; 1451 u32 clid; 1452 struct Qdisc *q = NULL; 1453 struct Qdisc *p = NULL; 1454 int err; 1455 1456 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1457 rtm_tca_policy, extack); 1458 if (err < 0) 1459 return err; 1460 1461 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1462 if (!dev) 1463 return -ENODEV; 1464 1465 clid = tcm->tcm_parent; 1466 if (clid) { 1467 if (clid != TC_H_ROOT) { 1468 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1469 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1470 if (!p) { 1471 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid"); 1472 return -ENOENT; 1473 } 1474 q = qdisc_leaf(p, clid); 1475 } else if (dev_ingress_queue(dev)) { 1476 q = dev_ingress_queue(dev)->qdisc_sleeping; 1477 } 1478 } else { 1479 q = rtnl_dereference(dev->qdisc); 1480 } 1481 if (!q) { 1482 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); 1483 return -ENOENT; 1484 } 1485 1486 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) { 1487 NL_SET_ERR_MSG(extack, "Invalid handle"); 1488 return -EINVAL; 1489 } 1490 } else { 1491 q = qdisc_lookup(dev, tcm->tcm_handle); 1492 if (!q) { 1493 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle"); 1494 return -ENOENT; 1495 } 1496 } 1497 1498 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1499 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1500 return -EINVAL; 1501 } 1502 1503 if (n->nlmsg_type == RTM_DELQDISC) { 1504 if (!clid) { 1505 NL_SET_ERR_MSG(extack, "Classid cannot be zero"); 1506 return -EINVAL; 1507 } 1508 if (q->handle == 0) { 1509 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero"); 1510 return -ENOENT; 1511 } 1512 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack); 1513 if (err != 0) 1514 return err; 1515 } else { 1516 qdisc_notify(net, skb, n, clid, NULL, q, NULL); 1517 } 1518 return 0; 1519 } 1520 1521 /* 1522 * Create/change qdisc. 1523 */ 1524 1525 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1526 struct netlink_ext_ack *extack) 1527 { 1528 struct net *net = sock_net(skb->sk); 1529 struct tcmsg *tcm; 1530 struct nlattr *tca[TCA_MAX + 1]; 1531 struct net_device *dev; 1532 u32 clid; 1533 struct Qdisc *q, *p; 1534 int err; 1535 1536 replay: 1537 /* Reinit, just in case something touches this. */ 1538 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1539 rtm_tca_policy, extack); 1540 if (err < 0) 1541 return err; 1542 1543 tcm = nlmsg_data(n); 1544 clid = tcm->tcm_parent; 1545 q = p = NULL; 1546 1547 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1548 if (!dev) 1549 return -ENODEV; 1550 1551 1552 if (clid) { 1553 if (clid != TC_H_ROOT) { 1554 if (clid != TC_H_INGRESS) { 1555 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1556 if (!p) { 1557 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); 1558 return -ENOENT; 1559 } 1560 q = qdisc_leaf(p, clid); 1561 } else if (dev_ingress_queue_create(dev)) { 1562 q = dev_ingress_queue(dev)->qdisc_sleeping; 1563 } 1564 } else { 1565 q = rtnl_dereference(dev->qdisc); 1566 } 1567 1568 /* It may be default qdisc, ignore it */ 1569 if (q && q->handle == 0) 1570 q = NULL; 1571 1572 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1573 if (tcm->tcm_handle) { 1574 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) { 1575 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override"); 1576 return -EEXIST; 1577 } 1578 if (TC_H_MIN(tcm->tcm_handle)) { 1579 NL_SET_ERR_MSG(extack, "Invalid minor handle"); 1580 return -EINVAL; 1581 } 1582 q = qdisc_lookup(dev, tcm->tcm_handle); 1583 if (!q) 1584 goto create_n_graft; 1585 if (n->nlmsg_flags & NLM_F_EXCL) { 1586 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override"); 1587 return -EEXIST; 1588 } 1589 if (tca[TCA_KIND] && 1590 nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1591 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1592 return -EINVAL; 1593 } 1594 if (q == p || 1595 (p && check_loop(q, p, 0))) { 1596 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected"); 1597 return -ELOOP; 1598 } 1599 qdisc_refcount_inc(q); 1600 goto graft; 1601 } else { 1602 if (!q) 1603 goto create_n_graft; 1604 1605 /* This magic test requires explanation. 1606 * 1607 * We know, that some child q is already 1608 * attached to this parent and have choice: 1609 * either to change it or to create/graft new one. 1610 * 1611 * 1. We are allowed to create/graft only 1612 * if CREATE and REPLACE flags are set. 1613 * 1614 * 2. If EXCL is set, requestor wanted to say, 1615 * that qdisc tcm_handle is not expected 1616 * to exist, so that we choose create/graft too. 1617 * 1618 * 3. The last case is when no flags are set. 1619 * Alas, it is sort of hole in API, we 1620 * cannot decide what to do unambiguously. 1621 * For now we select create/graft, if 1622 * user gave KIND, which does not match existing. 1623 */ 1624 if ((n->nlmsg_flags & NLM_F_CREATE) && 1625 (n->nlmsg_flags & NLM_F_REPLACE) && 1626 ((n->nlmsg_flags & NLM_F_EXCL) || 1627 (tca[TCA_KIND] && 1628 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1629 goto create_n_graft; 1630 } 1631 } 1632 } else { 1633 if (!tcm->tcm_handle) { 1634 NL_SET_ERR_MSG(extack, "Handle cannot be zero"); 1635 return -EINVAL; 1636 } 1637 q = qdisc_lookup(dev, tcm->tcm_handle); 1638 } 1639 1640 /* Change qdisc parameters */ 1641 if (!q) { 1642 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1643 return -ENOENT; 1644 } 1645 if (n->nlmsg_flags & NLM_F_EXCL) { 1646 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify"); 1647 return -EEXIST; 1648 } 1649 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1650 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1651 return -EINVAL; 1652 } 1653 err = qdisc_change(q, tca, extack); 1654 if (err == 0) 1655 qdisc_notify(net, skb, n, clid, NULL, q, extack); 1656 return err; 1657 1658 create_n_graft: 1659 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 1660 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag"); 1661 return -ENOENT; 1662 } 1663 if (clid == TC_H_INGRESS) { 1664 if (dev_ingress_queue(dev)) { 1665 q = qdisc_create(dev, dev_ingress_queue(dev), 1666 tcm->tcm_parent, tcm->tcm_parent, 1667 tca, &err, extack); 1668 } else { 1669 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device"); 1670 err = -ENOENT; 1671 } 1672 } else { 1673 struct netdev_queue *dev_queue; 1674 1675 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1676 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1677 else if (p) 1678 dev_queue = p->dev_queue; 1679 else 1680 dev_queue = netdev_get_tx_queue(dev, 0); 1681 1682 q = qdisc_create(dev, dev_queue, 1683 tcm->tcm_parent, tcm->tcm_handle, 1684 tca, &err, extack); 1685 } 1686 if (q == NULL) { 1687 if (err == -EAGAIN) 1688 goto replay; 1689 return err; 1690 } 1691 1692 graft: 1693 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack); 1694 if (err) { 1695 if (q) 1696 qdisc_put(q); 1697 return err; 1698 } 1699 1700 return 0; 1701 } 1702 1703 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1704 struct netlink_callback *cb, 1705 int *q_idx_p, int s_q_idx, bool recur, 1706 bool dump_invisible) 1707 { 1708 int ret = 0, q_idx = *q_idx_p; 1709 struct Qdisc *q; 1710 int b; 1711 1712 if (!root) 1713 return 0; 1714 1715 q = root; 1716 if (q_idx < s_q_idx) { 1717 q_idx++; 1718 } else { 1719 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1720 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1721 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1722 RTM_NEWQDISC, NULL) <= 0) 1723 goto done; 1724 q_idx++; 1725 } 1726 1727 /* If dumping singletons, there is no qdisc_dev(root) and the singleton 1728 * itself has already been dumped. 1729 * 1730 * If we've already dumped the top-level (ingress) qdisc above and the global 1731 * qdisc hashtable, we don't want to hit it again 1732 */ 1733 if (!qdisc_dev(root) || !recur) 1734 goto out; 1735 1736 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 1737 if (q_idx < s_q_idx) { 1738 q_idx++; 1739 continue; 1740 } 1741 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1742 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1743 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1744 RTM_NEWQDISC, NULL) <= 0) 1745 goto done; 1746 q_idx++; 1747 } 1748 1749 out: 1750 *q_idx_p = q_idx; 1751 return ret; 1752 done: 1753 ret = -1; 1754 goto out; 1755 } 1756 1757 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1758 { 1759 struct net *net = sock_net(skb->sk); 1760 int idx, q_idx; 1761 int s_idx, s_q_idx; 1762 struct net_device *dev; 1763 const struct nlmsghdr *nlh = cb->nlh; 1764 struct nlattr *tca[TCA_MAX + 1]; 1765 int err; 1766 1767 s_idx = cb->args[0]; 1768 s_q_idx = q_idx = cb->args[1]; 1769 1770 idx = 0; 1771 ASSERT_RTNL(); 1772 1773 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX, 1774 rtm_tca_policy, cb->extack); 1775 if (err < 0) 1776 return err; 1777 1778 for_each_netdev(net, dev) { 1779 struct netdev_queue *dev_queue; 1780 1781 if (idx < s_idx) 1782 goto cont; 1783 if (idx > s_idx) 1784 s_q_idx = 0; 1785 q_idx = 0; 1786 1787 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc), 1788 skb, cb, &q_idx, s_q_idx, 1789 true, tca[TCA_DUMP_INVISIBLE]) < 0) 1790 goto done; 1791 1792 dev_queue = dev_ingress_queue(dev); 1793 if (dev_queue && 1794 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1795 &q_idx, s_q_idx, false, 1796 tca[TCA_DUMP_INVISIBLE]) < 0) 1797 goto done; 1798 1799 cont: 1800 idx++; 1801 } 1802 1803 done: 1804 cb->args[0] = idx; 1805 cb->args[1] = q_idx; 1806 1807 return skb->len; 1808 } 1809 1810 1811 1812 /************************************************ 1813 * Traffic classes manipulation. * 1814 ************************************************/ 1815 1816 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1817 unsigned long cl, u32 portid, u32 seq, u16 flags, 1818 int event, struct netlink_ext_ack *extack) 1819 { 1820 struct tcmsg *tcm; 1821 struct nlmsghdr *nlh; 1822 unsigned char *b = skb_tail_pointer(skb); 1823 struct gnet_dump d; 1824 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1825 1826 cond_resched(); 1827 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1828 if (!nlh) 1829 goto out_nlmsg_trim; 1830 tcm = nlmsg_data(nlh); 1831 tcm->tcm_family = AF_UNSPEC; 1832 tcm->tcm__pad1 = 0; 1833 tcm->tcm__pad2 = 0; 1834 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1835 tcm->tcm_parent = q->handle; 1836 tcm->tcm_handle = q->handle; 1837 tcm->tcm_info = 0; 1838 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1839 goto nla_put_failure; 1840 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1841 goto nla_put_failure; 1842 1843 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1844 NULL, &d, TCA_PAD) < 0) 1845 goto nla_put_failure; 1846 1847 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1848 goto nla_put_failure; 1849 1850 if (gnet_stats_finish_copy(&d) < 0) 1851 goto nla_put_failure; 1852 1853 if (extack && extack->_msg && 1854 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg)) 1855 goto out_nlmsg_trim; 1856 1857 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1858 1859 return skb->len; 1860 1861 out_nlmsg_trim: 1862 nla_put_failure: 1863 nlmsg_trim(skb, b); 1864 return -1; 1865 } 1866 1867 static int tclass_notify(struct net *net, struct sk_buff *oskb, 1868 struct nlmsghdr *n, struct Qdisc *q, 1869 unsigned long cl, int event, struct netlink_ext_ack *extack) 1870 { 1871 struct sk_buff *skb; 1872 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1873 1874 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1875 if (!skb) 1876 return -ENOBUFS; 1877 1878 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event, extack) < 0) { 1879 kfree_skb(skb); 1880 return -EINVAL; 1881 } 1882 1883 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1884 n->nlmsg_flags & NLM_F_ECHO); 1885 } 1886 1887 static int tclass_del_notify(struct net *net, 1888 const struct Qdisc_class_ops *cops, 1889 struct sk_buff *oskb, struct nlmsghdr *n, 1890 struct Qdisc *q, unsigned long cl, 1891 struct netlink_ext_ack *extack) 1892 { 1893 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1894 struct sk_buff *skb; 1895 int err = 0; 1896 1897 if (!cops->delete) 1898 return -EOPNOTSUPP; 1899 1900 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1901 if (!skb) 1902 return -ENOBUFS; 1903 1904 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, 1905 RTM_DELTCLASS, extack) < 0) { 1906 kfree_skb(skb); 1907 return -EINVAL; 1908 } 1909 1910 err = cops->delete(q, cl, extack); 1911 if (err) { 1912 kfree_skb(skb); 1913 return err; 1914 } 1915 1916 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1917 n->nlmsg_flags & NLM_F_ECHO); 1918 return err; 1919 } 1920 1921 #ifdef CONFIG_NET_CLS 1922 1923 struct tcf_bind_args { 1924 struct tcf_walker w; 1925 unsigned long base; 1926 unsigned long cl; 1927 u32 classid; 1928 }; 1929 1930 static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 1931 { 1932 struct tcf_bind_args *a = (void *)arg; 1933 1934 if (n && tp->ops->bind_class) { 1935 struct Qdisc *q = tcf_block_q(tp->chain->block); 1936 1937 sch_tree_lock(q); 1938 tp->ops->bind_class(n, a->classid, a->cl, q, a->base); 1939 sch_tree_unlock(q); 1940 } 1941 return 0; 1942 } 1943 1944 struct tc_bind_class_args { 1945 struct qdisc_walker w; 1946 unsigned long new_cl; 1947 u32 portid; 1948 u32 clid; 1949 }; 1950 1951 static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl, 1952 struct qdisc_walker *w) 1953 { 1954 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w; 1955 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1956 struct tcf_block *block; 1957 struct tcf_chain *chain; 1958 1959 block = cops->tcf_block(q, cl, NULL); 1960 if (!block) 1961 return 0; 1962 for (chain = tcf_get_next_chain(block, NULL); 1963 chain; 1964 chain = tcf_get_next_chain(block, chain)) { 1965 struct tcf_proto *tp; 1966 1967 for (tp = tcf_get_next_proto(chain, NULL); 1968 tp; tp = tcf_get_next_proto(chain, tp)) { 1969 struct tcf_bind_args arg = {}; 1970 1971 arg.w.fn = tcf_node_bind; 1972 arg.classid = a->clid; 1973 arg.base = cl; 1974 arg.cl = a->new_cl; 1975 tp->ops->walk(tp, &arg.w, true); 1976 } 1977 } 1978 1979 return 0; 1980 } 1981 1982 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1983 unsigned long new_cl) 1984 { 1985 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1986 struct tc_bind_class_args args = {}; 1987 1988 if (!cops->tcf_block) 1989 return; 1990 args.portid = portid; 1991 args.clid = clid; 1992 args.new_cl = new_cl; 1993 args.w.fn = tc_bind_class_walker; 1994 q->ops->cl_ops->walk(q, &args.w); 1995 } 1996 1997 #else 1998 1999 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 2000 unsigned long new_cl) 2001 { 2002 } 2003 2004 #endif 2005 2006 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 2007 struct netlink_ext_ack *extack) 2008 { 2009 struct net *net = sock_net(skb->sk); 2010 struct tcmsg *tcm = nlmsg_data(n); 2011 struct nlattr *tca[TCA_MAX + 1]; 2012 struct net_device *dev; 2013 struct Qdisc *q = NULL; 2014 const struct Qdisc_class_ops *cops; 2015 unsigned long cl = 0; 2016 unsigned long new_cl; 2017 u32 portid; 2018 u32 clid; 2019 u32 qid; 2020 int err; 2021 2022 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 2023 rtm_tca_policy, extack); 2024 if (err < 0) 2025 return err; 2026 2027 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2028 if (!dev) 2029 return -ENODEV; 2030 2031 /* 2032 parent == TC_H_UNSPEC - unspecified parent. 2033 parent == TC_H_ROOT - class is root, which has no parent. 2034 parent == X:0 - parent is root class. 2035 parent == X:Y - parent is a node in hierarchy. 2036 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 2037 2038 handle == 0:0 - generate handle from kernel pool. 2039 handle == 0:Y - class is X:Y, where X:0 is qdisc. 2040 handle == X:Y - clear. 2041 handle == X:0 - root class. 2042 */ 2043 2044 /* Step 1. Determine qdisc handle X:0 */ 2045 2046 portid = tcm->tcm_parent; 2047 clid = tcm->tcm_handle; 2048 qid = TC_H_MAJ(clid); 2049 2050 if (portid != TC_H_ROOT) { 2051 u32 qid1 = TC_H_MAJ(portid); 2052 2053 if (qid && qid1) { 2054 /* If both majors are known, they must be identical. */ 2055 if (qid != qid1) 2056 return -EINVAL; 2057 } else if (qid1) { 2058 qid = qid1; 2059 } else if (qid == 0) 2060 qid = rtnl_dereference(dev->qdisc)->handle; 2061 2062 /* Now qid is genuine qdisc handle consistent 2063 * both with parent and child. 2064 * 2065 * TC_H_MAJ(portid) still may be unspecified, complete it now. 2066 */ 2067 if (portid) 2068 portid = TC_H_MAKE(qid, portid); 2069 } else { 2070 if (qid == 0) 2071 qid = rtnl_dereference(dev->qdisc)->handle; 2072 } 2073 2074 /* OK. Locate qdisc */ 2075 q = qdisc_lookup(dev, qid); 2076 if (!q) 2077 return -ENOENT; 2078 2079 /* An check that it supports classes */ 2080 cops = q->ops->cl_ops; 2081 if (cops == NULL) 2082 return -EINVAL; 2083 2084 /* Now try to get class */ 2085 if (clid == 0) { 2086 if (portid == TC_H_ROOT) 2087 clid = qid; 2088 } else 2089 clid = TC_H_MAKE(qid, clid); 2090 2091 if (clid) 2092 cl = cops->find(q, clid); 2093 2094 if (cl == 0) { 2095 err = -ENOENT; 2096 if (n->nlmsg_type != RTM_NEWTCLASS || 2097 !(n->nlmsg_flags & NLM_F_CREATE)) 2098 goto out; 2099 } else { 2100 switch (n->nlmsg_type) { 2101 case RTM_NEWTCLASS: 2102 err = -EEXIST; 2103 if (n->nlmsg_flags & NLM_F_EXCL) 2104 goto out; 2105 break; 2106 case RTM_DELTCLASS: 2107 err = tclass_del_notify(net, cops, skb, n, q, cl, extack); 2108 /* Unbind the class with flilters with 0 */ 2109 tc_bind_tclass(q, portid, clid, 0); 2110 goto out; 2111 case RTM_GETTCLASS: 2112 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS, extack); 2113 goto out; 2114 default: 2115 err = -EINVAL; 2116 goto out; 2117 } 2118 } 2119 2120 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 2121 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes"); 2122 return -EOPNOTSUPP; 2123 } 2124 2125 new_cl = cl; 2126 err = -EOPNOTSUPP; 2127 if (cops->change) 2128 err = cops->change(q, clid, portid, tca, &new_cl, extack); 2129 if (err == 0) { 2130 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack); 2131 /* We just create a new class, need to do reverse binding. */ 2132 if (cl != new_cl) 2133 tc_bind_tclass(q, portid, clid, new_cl); 2134 } 2135 out: 2136 return err; 2137 } 2138 2139 struct qdisc_dump_args { 2140 struct qdisc_walker w; 2141 struct sk_buff *skb; 2142 struct netlink_callback *cb; 2143 }; 2144 2145 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, 2146 struct qdisc_walker *arg) 2147 { 2148 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 2149 2150 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 2151 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2152 RTM_NEWTCLASS, NULL); 2153 } 2154 2155 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 2156 struct tcmsg *tcm, struct netlink_callback *cb, 2157 int *t_p, int s_t) 2158 { 2159 struct qdisc_dump_args arg; 2160 2161 if (tc_qdisc_dump_ignore(q, false) || 2162 *t_p < s_t || !q->ops->cl_ops || 2163 (tcm->tcm_parent && 2164 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 2165 (*t_p)++; 2166 return 0; 2167 } 2168 if (*t_p > s_t) 2169 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 2170 arg.w.fn = qdisc_class_dump; 2171 arg.skb = skb; 2172 arg.cb = cb; 2173 arg.w.stop = 0; 2174 arg.w.skip = cb->args[1]; 2175 arg.w.count = 0; 2176 q->ops->cl_ops->walk(q, &arg.w); 2177 cb->args[1] = arg.w.count; 2178 if (arg.w.stop) 2179 return -1; 2180 (*t_p)++; 2181 return 0; 2182 } 2183 2184 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 2185 struct tcmsg *tcm, struct netlink_callback *cb, 2186 int *t_p, int s_t, bool recur) 2187 { 2188 struct Qdisc *q; 2189 int b; 2190 2191 if (!root) 2192 return 0; 2193 2194 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 2195 return -1; 2196 2197 if (!qdisc_dev(root) || !recur) 2198 return 0; 2199 2200 if (tcm->tcm_parent) { 2201 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent)); 2202 if (q && q != root && 2203 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2204 return -1; 2205 return 0; 2206 } 2207 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 2208 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2209 return -1; 2210 } 2211 2212 return 0; 2213 } 2214 2215 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 2216 { 2217 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2218 struct net *net = sock_net(skb->sk); 2219 struct netdev_queue *dev_queue; 2220 struct net_device *dev; 2221 int t, s_t; 2222 2223 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2224 return 0; 2225 dev = dev_get_by_index(net, tcm->tcm_ifindex); 2226 if (!dev) 2227 return 0; 2228 2229 s_t = cb->args[0]; 2230 t = 0; 2231 2232 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc), 2233 skb, tcm, cb, &t, s_t, true) < 0) 2234 goto done; 2235 2236 dev_queue = dev_ingress_queue(dev); 2237 if (dev_queue && 2238 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 2239 &t, s_t, false) < 0) 2240 goto done; 2241 2242 done: 2243 cb->args[0] = t; 2244 2245 dev_put(dev); 2246 return skb->len; 2247 } 2248 2249 #ifdef CONFIG_PROC_FS 2250 static int psched_show(struct seq_file *seq, void *v) 2251 { 2252 seq_printf(seq, "%08x %08x %08x %08x\n", 2253 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 2254 1000000, 2255 (u32)NSEC_PER_SEC / hrtimer_resolution); 2256 2257 return 0; 2258 } 2259 2260 static int __net_init psched_net_init(struct net *net) 2261 { 2262 struct proc_dir_entry *e; 2263 2264 e = proc_create_single("psched", 0, net->proc_net, psched_show); 2265 if (e == NULL) 2266 return -ENOMEM; 2267 2268 return 0; 2269 } 2270 2271 static void __net_exit psched_net_exit(struct net *net) 2272 { 2273 remove_proc_entry("psched", net->proc_net); 2274 } 2275 #else 2276 static int __net_init psched_net_init(struct net *net) 2277 { 2278 return 0; 2279 } 2280 2281 static void __net_exit psched_net_exit(struct net *net) 2282 { 2283 } 2284 #endif 2285 2286 static struct pernet_operations psched_net_ops = { 2287 .init = psched_net_init, 2288 .exit = psched_net_exit, 2289 }; 2290 2291 DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper); 2292 2293 static int __init pktsched_init(void) 2294 { 2295 int err; 2296 2297 err = register_pernet_subsys(&psched_net_ops); 2298 if (err) { 2299 pr_err("pktsched_init: " 2300 "cannot initialize per netns operations\n"); 2301 return err; 2302 } 2303 2304 register_qdisc(&pfifo_fast_ops); 2305 register_qdisc(&pfifo_qdisc_ops); 2306 register_qdisc(&bfifo_qdisc_ops); 2307 register_qdisc(&pfifo_head_drop_qdisc_ops); 2308 register_qdisc(&mq_qdisc_ops); 2309 register_qdisc(&noqueue_qdisc_ops); 2310 2311 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0); 2312 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0); 2313 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, 2314 0); 2315 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0); 2316 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0); 2317 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, 2318 0); 2319 2320 tc_wrapper_init(); 2321 2322 return 0; 2323 } 2324 2325 subsys_initcall(pktsched_init); 2326