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 (ops->init) { 1286 err = ops->init(sch, tca[TCA_OPTIONS], extack); 1287 if (err != 0) 1288 goto err_out5; 1289 } 1290 1291 if (tca[TCA_STAB]) { 1292 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1293 if (IS_ERR(stab)) { 1294 err = PTR_ERR(stab); 1295 goto err_out4; 1296 } 1297 rcu_assign_pointer(sch->stab, stab); 1298 } 1299 if (tca[TCA_RATE]) { 1300 err = -EOPNOTSUPP; 1301 if (sch->flags & TCQ_F_MQROOT) { 1302 NL_SET_ERR_MSG(extack, "Cannot attach rate estimator to a multi-queue root qdisc"); 1303 goto err_out4; 1304 } 1305 1306 err = gen_new_estimator(&sch->bstats, 1307 sch->cpu_bstats, 1308 &sch->rate_est, 1309 NULL, 1310 true, 1311 tca[TCA_RATE]); 1312 if (err) { 1313 NL_SET_ERR_MSG(extack, "Failed to generate new estimator"); 1314 goto err_out4; 1315 } 1316 } 1317 1318 qdisc_hash_add(sch, false); 1319 trace_qdisc_create(ops, dev, parent); 1320 1321 return sch; 1322 1323 err_out5: 1324 /* ops->init() failed, we call ->destroy() like qdisc_create_dflt() */ 1325 if (ops->destroy) 1326 ops->destroy(sch); 1327 err_out3: 1328 netdev_put(dev, &sch->dev_tracker); 1329 qdisc_free(sch); 1330 err_out2: 1331 module_put(ops->owner); 1332 err_out: 1333 *errp = err; 1334 return NULL; 1335 1336 err_out4: 1337 /* 1338 * Any broken qdiscs that would require a ops->reset() here? 1339 * The qdisc was never in action so it shouldn't be necessary. 1340 */ 1341 qdisc_put_stab(rtnl_dereference(sch->stab)); 1342 if (ops->destroy) 1343 ops->destroy(sch); 1344 goto err_out3; 1345 } 1346 1347 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca, 1348 struct netlink_ext_ack *extack) 1349 { 1350 struct qdisc_size_table *ostab, *stab = NULL; 1351 int err = 0; 1352 1353 if (tca[TCA_OPTIONS]) { 1354 if (!sch->ops->change) { 1355 NL_SET_ERR_MSG(extack, "Change operation not supported by specified qdisc"); 1356 return -EINVAL; 1357 } 1358 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 1359 NL_SET_ERR_MSG(extack, "Change of blocks is not supported"); 1360 return -EOPNOTSUPP; 1361 } 1362 err = sch->ops->change(sch, tca[TCA_OPTIONS], extack); 1363 if (err) 1364 return err; 1365 } 1366 1367 if (tca[TCA_STAB]) { 1368 stab = qdisc_get_stab(tca[TCA_STAB], extack); 1369 if (IS_ERR(stab)) 1370 return PTR_ERR(stab); 1371 } 1372 1373 ostab = rtnl_dereference(sch->stab); 1374 rcu_assign_pointer(sch->stab, stab); 1375 qdisc_put_stab(ostab); 1376 1377 if (tca[TCA_RATE]) { 1378 /* NB: ignores errors from replace_estimator 1379 because change can't be undone. */ 1380 if (sch->flags & TCQ_F_MQROOT) 1381 goto out; 1382 gen_replace_estimator(&sch->bstats, 1383 sch->cpu_bstats, 1384 &sch->rate_est, 1385 NULL, 1386 true, 1387 tca[TCA_RATE]); 1388 } 1389 out: 1390 return 0; 1391 } 1392 1393 struct check_loop_arg { 1394 struct qdisc_walker w; 1395 struct Qdisc *p; 1396 int depth; 1397 }; 1398 1399 static int check_loop_fn(struct Qdisc *q, unsigned long cl, 1400 struct qdisc_walker *w); 1401 1402 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 1403 { 1404 struct check_loop_arg arg; 1405 1406 if (q->ops->cl_ops == NULL) 1407 return 0; 1408 1409 arg.w.stop = arg.w.skip = arg.w.count = 0; 1410 arg.w.fn = check_loop_fn; 1411 arg.depth = depth; 1412 arg.p = p; 1413 q->ops->cl_ops->walk(q, &arg.w); 1414 return arg.w.stop ? -ELOOP : 0; 1415 } 1416 1417 static int 1418 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 1419 { 1420 struct Qdisc *leaf; 1421 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1422 struct check_loop_arg *arg = (struct check_loop_arg *)w; 1423 1424 leaf = cops->leaf(q, cl); 1425 if (leaf) { 1426 if (leaf == arg->p || arg->depth > 7) 1427 return -ELOOP; 1428 return check_loop(leaf, arg->p, arg->depth + 1); 1429 } 1430 return 0; 1431 } 1432 1433 const struct nla_policy rtm_tca_policy[TCA_MAX + 1] = { 1434 [TCA_KIND] = { .type = NLA_STRING }, 1435 [TCA_RATE] = { .type = NLA_BINARY, 1436 .len = sizeof(struct tc_estimator) }, 1437 [TCA_STAB] = { .type = NLA_NESTED }, 1438 [TCA_DUMP_INVISIBLE] = { .type = NLA_FLAG }, 1439 [TCA_CHAIN] = { .type = NLA_U32 }, 1440 [TCA_INGRESS_BLOCK] = { .type = NLA_U32 }, 1441 [TCA_EGRESS_BLOCK] = { .type = NLA_U32 }, 1442 }; 1443 1444 /* 1445 * Delete/get qdisc. 1446 */ 1447 1448 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1449 struct netlink_ext_ack *extack) 1450 { 1451 struct net *net = sock_net(skb->sk); 1452 struct tcmsg *tcm = nlmsg_data(n); 1453 struct nlattr *tca[TCA_MAX + 1]; 1454 struct net_device *dev; 1455 u32 clid; 1456 struct Qdisc *q = NULL; 1457 struct Qdisc *p = NULL; 1458 int err; 1459 1460 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1461 rtm_tca_policy, extack); 1462 if (err < 0) 1463 return err; 1464 1465 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1466 if (!dev) 1467 return -ENODEV; 1468 1469 clid = tcm->tcm_parent; 1470 if (clid) { 1471 if (clid != TC_H_ROOT) { 1472 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 1473 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1474 if (!p) { 1475 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified classid"); 1476 return -ENOENT; 1477 } 1478 q = qdisc_leaf(p, clid); 1479 } else if (dev_ingress_queue(dev)) { 1480 q = dev_ingress_queue(dev)->qdisc_sleeping; 1481 } 1482 } else { 1483 q = rtnl_dereference(dev->qdisc); 1484 } 1485 if (!q) { 1486 NL_SET_ERR_MSG(extack, "Cannot find specified qdisc on specified device"); 1487 return -ENOENT; 1488 } 1489 1490 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) { 1491 NL_SET_ERR_MSG(extack, "Invalid handle"); 1492 return -EINVAL; 1493 } 1494 } else { 1495 q = qdisc_lookup(dev, tcm->tcm_handle); 1496 if (!q) { 1497 NL_SET_ERR_MSG(extack, "Failed to find qdisc with specified handle"); 1498 return -ENOENT; 1499 } 1500 } 1501 1502 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1503 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1504 return -EINVAL; 1505 } 1506 1507 if (n->nlmsg_type == RTM_DELQDISC) { 1508 if (!clid) { 1509 NL_SET_ERR_MSG(extack, "Classid cannot be zero"); 1510 return -EINVAL; 1511 } 1512 if (q->handle == 0) { 1513 NL_SET_ERR_MSG(extack, "Cannot delete qdisc with handle of zero"); 1514 return -ENOENT; 1515 } 1516 err = qdisc_graft(dev, p, skb, n, clid, NULL, q, extack); 1517 if (err != 0) 1518 return err; 1519 } else { 1520 qdisc_notify(net, skb, n, clid, NULL, q, NULL); 1521 } 1522 return 0; 1523 } 1524 1525 /* 1526 * Create/change qdisc. 1527 */ 1528 1529 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 1530 struct netlink_ext_ack *extack) 1531 { 1532 struct net *net = sock_net(skb->sk); 1533 struct tcmsg *tcm; 1534 struct nlattr *tca[TCA_MAX + 1]; 1535 struct net_device *dev; 1536 u32 clid; 1537 struct Qdisc *q, *p; 1538 int err; 1539 1540 replay: 1541 /* Reinit, just in case something touches this. */ 1542 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 1543 rtm_tca_policy, extack); 1544 if (err < 0) 1545 return err; 1546 1547 tcm = nlmsg_data(n); 1548 clid = tcm->tcm_parent; 1549 q = p = NULL; 1550 1551 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 1552 if (!dev) 1553 return -ENODEV; 1554 1555 1556 if (clid) { 1557 if (clid != TC_H_ROOT) { 1558 if (clid != TC_H_INGRESS) { 1559 p = qdisc_lookup(dev, TC_H_MAJ(clid)); 1560 if (!p) { 1561 NL_SET_ERR_MSG(extack, "Failed to find specified qdisc"); 1562 return -ENOENT; 1563 } 1564 q = qdisc_leaf(p, clid); 1565 } else if (dev_ingress_queue_create(dev)) { 1566 q = dev_ingress_queue(dev)->qdisc_sleeping; 1567 } 1568 } else { 1569 q = rtnl_dereference(dev->qdisc); 1570 } 1571 1572 /* It may be default qdisc, ignore it */ 1573 if (q && q->handle == 0) 1574 q = NULL; 1575 1576 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1577 if (tcm->tcm_handle) { 1578 if (q && !(n->nlmsg_flags & NLM_F_REPLACE)) { 1579 NL_SET_ERR_MSG(extack, "NLM_F_REPLACE needed to override"); 1580 return -EEXIST; 1581 } 1582 if (TC_H_MIN(tcm->tcm_handle)) { 1583 NL_SET_ERR_MSG(extack, "Invalid minor handle"); 1584 return -EINVAL; 1585 } 1586 q = qdisc_lookup(dev, tcm->tcm_handle); 1587 if (!q) 1588 goto create_n_graft; 1589 if (n->nlmsg_flags & NLM_F_EXCL) { 1590 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot override"); 1591 return -EEXIST; 1592 } 1593 if (tca[TCA_KIND] && 1594 nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1595 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1596 return -EINVAL; 1597 } 1598 if (q == p || 1599 (p && check_loop(q, p, 0))) { 1600 NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected"); 1601 return -ELOOP; 1602 } 1603 qdisc_refcount_inc(q); 1604 goto graft; 1605 } else { 1606 if (!q) 1607 goto create_n_graft; 1608 1609 /* This magic test requires explanation. 1610 * 1611 * We know, that some child q is already 1612 * attached to this parent and have choice: 1613 * either to change it or to create/graft new one. 1614 * 1615 * 1. We are allowed to create/graft only 1616 * if CREATE and REPLACE flags are set. 1617 * 1618 * 2. If EXCL is set, requestor wanted to say, 1619 * that qdisc tcm_handle is not expected 1620 * to exist, so that we choose create/graft too. 1621 * 1622 * 3. The last case is when no flags are set. 1623 * Alas, it is sort of hole in API, we 1624 * cannot decide what to do unambiguously. 1625 * For now we select create/graft, if 1626 * user gave KIND, which does not match existing. 1627 */ 1628 if ((n->nlmsg_flags & NLM_F_CREATE) && 1629 (n->nlmsg_flags & NLM_F_REPLACE) && 1630 ((n->nlmsg_flags & NLM_F_EXCL) || 1631 (tca[TCA_KIND] && 1632 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1633 goto create_n_graft; 1634 } 1635 } 1636 } else { 1637 if (!tcm->tcm_handle) { 1638 NL_SET_ERR_MSG(extack, "Handle cannot be zero"); 1639 return -EINVAL; 1640 } 1641 q = qdisc_lookup(dev, tcm->tcm_handle); 1642 } 1643 1644 /* Change qdisc parameters */ 1645 if (!q) { 1646 NL_SET_ERR_MSG(extack, "Specified qdisc not found"); 1647 return -ENOENT; 1648 } 1649 if (n->nlmsg_flags & NLM_F_EXCL) { 1650 NL_SET_ERR_MSG(extack, "Exclusivity flag on, cannot modify"); 1651 return -EEXIST; 1652 } 1653 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) { 1654 NL_SET_ERR_MSG(extack, "Invalid qdisc name"); 1655 return -EINVAL; 1656 } 1657 err = qdisc_change(q, tca, extack); 1658 if (err == 0) 1659 qdisc_notify(net, skb, n, clid, NULL, q, extack); 1660 return err; 1661 1662 create_n_graft: 1663 if (!(n->nlmsg_flags & NLM_F_CREATE)) { 1664 NL_SET_ERR_MSG(extack, "Qdisc not found. To create specify NLM_F_CREATE flag"); 1665 return -ENOENT; 1666 } 1667 if (clid == TC_H_INGRESS) { 1668 if (dev_ingress_queue(dev)) { 1669 q = qdisc_create(dev, dev_ingress_queue(dev), 1670 tcm->tcm_parent, tcm->tcm_parent, 1671 tca, &err, extack); 1672 } else { 1673 NL_SET_ERR_MSG(extack, "Cannot find ingress queue for specified device"); 1674 err = -ENOENT; 1675 } 1676 } else { 1677 struct netdev_queue *dev_queue; 1678 1679 if (p && p->ops->cl_ops && p->ops->cl_ops->select_queue) 1680 dev_queue = p->ops->cl_ops->select_queue(p, tcm); 1681 else if (p) 1682 dev_queue = p->dev_queue; 1683 else 1684 dev_queue = netdev_get_tx_queue(dev, 0); 1685 1686 q = qdisc_create(dev, dev_queue, 1687 tcm->tcm_parent, tcm->tcm_handle, 1688 tca, &err, extack); 1689 } 1690 if (q == NULL) { 1691 if (err == -EAGAIN) 1692 goto replay; 1693 return err; 1694 } 1695 1696 graft: 1697 err = qdisc_graft(dev, p, skb, n, clid, q, NULL, extack); 1698 if (err) { 1699 if (q) 1700 qdisc_put(q); 1701 return err; 1702 } 1703 1704 return 0; 1705 } 1706 1707 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1708 struct netlink_callback *cb, 1709 int *q_idx_p, int s_q_idx, bool recur, 1710 bool dump_invisible) 1711 { 1712 int ret = 0, q_idx = *q_idx_p; 1713 struct Qdisc *q; 1714 int b; 1715 1716 if (!root) 1717 return 0; 1718 1719 q = root; 1720 if (q_idx < s_q_idx) { 1721 q_idx++; 1722 } else { 1723 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1724 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1725 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1726 RTM_NEWQDISC, NULL) <= 0) 1727 goto done; 1728 q_idx++; 1729 } 1730 1731 /* If dumping singletons, there is no qdisc_dev(root) and the singleton 1732 * itself has already been dumped. 1733 * 1734 * If we've already dumped the top-level (ingress) qdisc above and the global 1735 * qdisc hashtable, we don't want to hit it again 1736 */ 1737 if (!qdisc_dev(root) || !recur) 1738 goto out; 1739 1740 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 1741 if (q_idx < s_q_idx) { 1742 q_idx++; 1743 continue; 1744 } 1745 if (!tc_qdisc_dump_ignore(q, dump_invisible) && 1746 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).portid, 1747 cb->nlh->nlmsg_seq, NLM_F_MULTI, 1748 RTM_NEWQDISC, NULL) <= 0) 1749 goto done; 1750 q_idx++; 1751 } 1752 1753 out: 1754 *q_idx_p = q_idx; 1755 return ret; 1756 done: 1757 ret = -1; 1758 goto out; 1759 } 1760 1761 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1762 { 1763 struct net *net = sock_net(skb->sk); 1764 int idx, q_idx; 1765 int s_idx, s_q_idx; 1766 struct net_device *dev; 1767 const struct nlmsghdr *nlh = cb->nlh; 1768 struct nlattr *tca[TCA_MAX + 1]; 1769 int err; 1770 1771 s_idx = cb->args[0]; 1772 s_q_idx = q_idx = cb->args[1]; 1773 1774 idx = 0; 1775 ASSERT_RTNL(); 1776 1777 err = nlmsg_parse_deprecated(nlh, sizeof(struct tcmsg), tca, TCA_MAX, 1778 rtm_tca_policy, cb->extack); 1779 if (err < 0) 1780 return err; 1781 1782 for_each_netdev(net, dev) { 1783 struct netdev_queue *dev_queue; 1784 1785 if (idx < s_idx) 1786 goto cont; 1787 if (idx > s_idx) 1788 s_q_idx = 0; 1789 q_idx = 0; 1790 1791 if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc), 1792 skb, cb, &q_idx, s_q_idx, 1793 true, tca[TCA_DUMP_INVISIBLE]) < 0) 1794 goto done; 1795 1796 dev_queue = dev_ingress_queue(dev); 1797 if (dev_queue && 1798 tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, 1799 &q_idx, s_q_idx, false, 1800 tca[TCA_DUMP_INVISIBLE]) < 0) 1801 goto done; 1802 1803 cont: 1804 idx++; 1805 } 1806 1807 done: 1808 cb->args[0] = idx; 1809 cb->args[1] = q_idx; 1810 1811 return skb->len; 1812 } 1813 1814 1815 1816 /************************************************ 1817 * Traffic classes manipulation. * 1818 ************************************************/ 1819 1820 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1821 unsigned long cl, u32 portid, u32 seq, u16 flags, 1822 int event, struct netlink_ext_ack *extack) 1823 { 1824 struct tcmsg *tcm; 1825 struct nlmsghdr *nlh; 1826 unsigned char *b = skb_tail_pointer(skb); 1827 struct gnet_dump d; 1828 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1829 1830 cond_resched(); 1831 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); 1832 if (!nlh) 1833 goto out_nlmsg_trim; 1834 tcm = nlmsg_data(nlh); 1835 tcm->tcm_family = AF_UNSPEC; 1836 tcm->tcm__pad1 = 0; 1837 tcm->tcm__pad2 = 0; 1838 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1839 tcm->tcm_parent = q->handle; 1840 tcm->tcm_handle = q->handle; 1841 tcm->tcm_info = 0; 1842 if (nla_put_string(skb, TCA_KIND, q->ops->id)) 1843 goto nla_put_failure; 1844 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1845 goto nla_put_failure; 1846 1847 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1848 NULL, &d, TCA_PAD) < 0) 1849 goto nla_put_failure; 1850 1851 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1852 goto nla_put_failure; 1853 1854 if (gnet_stats_finish_copy(&d) < 0) 1855 goto nla_put_failure; 1856 1857 if (extack && extack->_msg && 1858 nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg)) 1859 goto out_nlmsg_trim; 1860 1861 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1862 1863 return skb->len; 1864 1865 out_nlmsg_trim: 1866 nla_put_failure: 1867 nlmsg_trim(skb, b); 1868 return -1; 1869 } 1870 1871 static int tclass_notify(struct net *net, struct sk_buff *oskb, 1872 struct nlmsghdr *n, struct Qdisc *q, 1873 unsigned long cl, int event, struct netlink_ext_ack *extack) 1874 { 1875 struct sk_buff *skb; 1876 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1877 1878 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1879 if (!skb) 1880 return -ENOBUFS; 1881 1882 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, event, extack) < 0) { 1883 kfree_skb(skb); 1884 return -EINVAL; 1885 } 1886 1887 return rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1888 n->nlmsg_flags & NLM_F_ECHO); 1889 } 1890 1891 static int tclass_del_notify(struct net *net, 1892 const struct Qdisc_class_ops *cops, 1893 struct sk_buff *oskb, struct nlmsghdr *n, 1894 struct Qdisc *q, unsigned long cl, 1895 struct netlink_ext_ack *extack) 1896 { 1897 u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; 1898 struct sk_buff *skb; 1899 int err = 0; 1900 1901 if (!cops->delete) 1902 return -EOPNOTSUPP; 1903 1904 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1905 if (!skb) 1906 return -ENOBUFS; 1907 1908 if (tc_fill_tclass(skb, q, cl, portid, n->nlmsg_seq, 0, 1909 RTM_DELTCLASS, extack) < 0) { 1910 kfree_skb(skb); 1911 return -EINVAL; 1912 } 1913 1914 err = cops->delete(q, cl, extack); 1915 if (err) { 1916 kfree_skb(skb); 1917 return err; 1918 } 1919 1920 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, 1921 n->nlmsg_flags & NLM_F_ECHO); 1922 return err; 1923 } 1924 1925 #ifdef CONFIG_NET_CLS 1926 1927 struct tcf_bind_args { 1928 struct tcf_walker w; 1929 unsigned long base; 1930 unsigned long cl; 1931 u32 classid; 1932 }; 1933 1934 static int tcf_node_bind(struct tcf_proto *tp, void *n, struct tcf_walker *arg) 1935 { 1936 struct tcf_bind_args *a = (void *)arg; 1937 1938 if (n && tp->ops->bind_class) { 1939 struct Qdisc *q = tcf_block_q(tp->chain->block); 1940 1941 sch_tree_lock(q); 1942 tp->ops->bind_class(n, a->classid, a->cl, q, a->base); 1943 sch_tree_unlock(q); 1944 } 1945 return 0; 1946 } 1947 1948 struct tc_bind_class_args { 1949 struct qdisc_walker w; 1950 unsigned long new_cl; 1951 u32 portid; 1952 u32 clid; 1953 }; 1954 1955 static int tc_bind_class_walker(struct Qdisc *q, unsigned long cl, 1956 struct qdisc_walker *w) 1957 { 1958 struct tc_bind_class_args *a = (struct tc_bind_class_args *)w; 1959 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1960 struct tcf_block *block; 1961 struct tcf_chain *chain; 1962 1963 block = cops->tcf_block(q, cl, NULL); 1964 if (!block) 1965 return 0; 1966 for (chain = tcf_get_next_chain(block, NULL); 1967 chain; 1968 chain = tcf_get_next_chain(block, chain)) { 1969 struct tcf_proto *tp; 1970 1971 for (tp = tcf_get_next_proto(chain, NULL); 1972 tp; tp = tcf_get_next_proto(chain, tp)) { 1973 struct tcf_bind_args arg = {}; 1974 1975 arg.w.fn = tcf_node_bind; 1976 arg.classid = a->clid; 1977 arg.base = cl; 1978 arg.cl = a->new_cl; 1979 tp->ops->walk(tp, &arg.w, true); 1980 } 1981 } 1982 1983 return 0; 1984 } 1985 1986 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 1987 unsigned long new_cl) 1988 { 1989 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 1990 struct tc_bind_class_args args = {}; 1991 1992 if (!cops->tcf_block) 1993 return; 1994 args.portid = portid; 1995 args.clid = clid; 1996 args.new_cl = new_cl; 1997 args.w.fn = tc_bind_class_walker; 1998 q->ops->cl_ops->walk(q, &args.w); 1999 } 2000 2001 #else 2002 2003 static void tc_bind_tclass(struct Qdisc *q, u32 portid, u32 clid, 2004 unsigned long new_cl) 2005 { 2006 } 2007 2008 #endif 2009 2010 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 2011 struct netlink_ext_ack *extack) 2012 { 2013 struct net *net = sock_net(skb->sk); 2014 struct tcmsg *tcm = nlmsg_data(n); 2015 struct nlattr *tca[TCA_MAX + 1]; 2016 struct net_device *dev; 2017 struct Qdisc *q = NULL; 2018 const struct Qdisc_class_ops *cops; 2019 unsigned long cl = 0; 2020 unsigned long new_cl; 2021 u32 portid; 2022 u32 clid; 2023 u32 qid; 2024 int err; 2025 2026 err = nlmsg_parse_deprecated(n, sizeof(*tcm), tca, TCA_MAX, 2027 rtm_tca_policy, extack); 2028 if (err < 0) 2029 return err; 2030 2031 dev = __dev_get_by_index(net, tcm->tcm_ifindex); 2032 if (!dev) 2033 return -ENODEV; 2034 2035 /* 2036 parent == TC_H_UNSPEC - unspecified parent. 2037 parent == TC_H_ROOT - class is root, which has no parent. 2038 parent == X:0 - parent is root class. 2039 parent == X:Y - parent is a node in hierarchy. 2040 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 2041 2042 handle == 0:0 - generate handle from kernel pool. 2043 handle == 0:Y - class is X:Y, where X:0 is qdisc. 2044 handle == X:Y - clear. 2045 handle == X:0 - root class. 2046 */ 2047 2048 /* Step 1. Determine qdisc handle X:0 */ 2049 2050 portid = tcm->tcm_parent; 2051 clid = tcm->tcm_handle; 2052 qid = TC_H_MAJ(clid); 2053 2054 if (portid != TC_H_ROOT) { 2055 u32 qid1 = TC_H_MAJ(portid); 2056 2057 if (qid && qid1) { 2058 /* If both majors are known, they must be identical. */ 2059 if (qid != qid1) 2060 return -EINVAL; 2061 } else if (qid1) { 2062 qid = qid1; 2063 } else if (qid == 0) 2064 qid = rtnl_dereference(dev->qdisc)->handle; 2065 2066 /* Now qid is genuine qdisc handle consistent 2067 * both with parent and child. 2068 * 2069 * TC_H_MAJ(portid) still may be unspecified, complete it now. 2070 */ 2071 if (portid) 2072 portid = TC_H_MAKE(qid, portid); 2073 } else { 2074 if (qid == 0) 2075 qid = rtnl_dereference(dev->qdisc)->handle; 2076 } 2077 2078 /* OK. Locate qdisc */ 2079 q = qdisc_lookup(dev, qid); 2080 if (!q) 2081 return -ENOENT; 2082 2083 /* An check that it supports classes */ 2084 cops = q->ops->cl_ops; 2085 if (cops == NULL) 2086 return -EINVAL; 2087 2088 /* Now try to get class */ 2089 if (clid == 0) { 2090 if (portid == TC_H_ROOT) 2091 clid = qid; 2092 } else 2093 clid = TC_H_MAKE(qid, clid); 2094 2095 if (clid) 2096 cl = cops->find(q, clid); 2097 2098 if (cl == 0) { 2099 err = -ENOENT; 2100 if (n->nlmsg_type != RTM_NEWTCLASS || 2101 !(n->nlmsg_flags & NLM_F_CREATE)) 2102 goto out; 2103 } else { 2104 switch (n->nlmsg_type) { 2105 case RTM_NEWTCLASS: 2106 err = -EEXIST; 2107 if (n->nlmsg_flags & NLM_F_EXCL) 2108 goto out; 2109 break; 2110 case RTM_DELTCLASS: 2111 err = tclass_del_notify(net, cops, skb, n, q, cl, extack); 2112 /* Unbind the class with flilters with 0 */ 2113 tc_bind_tclass(q, portid, clid, 0); 2114 goto out; 2115 case RTM_GETTCLASS: 2116 err = tclass_notify(net, skb, n, q, cl, RTM_NEWTCLASS, extack); 2117 goto out; 2118 default: 2119 err = -EINVAL; 2120 goto out; 2121 } 2122 } 2123 2124 if (tca[TCA_INGRESS_BLOCK] || tca[TCA_EGRESS_BLOCK]) { 2125 NL_SET_ERR_MSG(extack, "Shared blocks are not supported for classes"); 2126 return -EOPNOTSUPP; 2127 } 2128 2129 new_cl = cl; 2130 err = -EOPNOTSUPP; 2131 if (cops->change) 2132 err = cops->change(q, clid, portid, tca, &new_cl, extack); 2133 if (err == 0) { 2134 tclass_notify(net, skb, n, q, new_cl, RTM_NEWTCLASS, extack); 2135 /* We just create a new class, need to do reverse binding. */ 2136 if (cl != new_cl) 2137 tc_bind_tclass(q, portid, clid, new_cl); 2138 } 2139 out: 2140 return err; 2141 } 2142 2143 struct qdisc_dump_args { 2144 struct qdisc_walker w; 2145 struct sk_buff *skb; 2146 struct netlink_callback *cb; 2147 }; 2148 2149 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, 2150 struct qdisc_walker *arg) 2151 { 2152 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 2153 2154 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).portid, 2155 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, 2156 RTM_NEWTCLASS, NULL); 2157 } 2158 2159 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 2160 struct tcmsg *tcm, struct netlink_callback *cb, 2161 int *t_p, int s_t) 2162 { 2163 struct qdisc_dump_args arg; 2164 2165 if (tc_qdisc_dump_ignore(q, false) || 2166 *t_p < s_t || !q->ops->cl_ops || 2167 (tcm->tcm_parent && 2168 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 2169 (*t_p)++; 2170 return 0; 2171 } 2172 if (*t_p > s_t) 2173 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 2174 arg.w.fn = qdisc_class_dump; 2175 arg.skb = skb; 2176 arg.cb = cb; 2177 arg.w.stop = 0; 2178 arg.w.skip = cb->args[1]; 2179 arg.w.count = 0; 2180 q->ops->cl_ops->walk(q, &arg.w); 2181 cb->args[1] = arg.w.count; 2182 if (arg.w.stop) 2183 return -1; 2184 (*t_p)++; 2185 return 0; 2186 } 2187 2188 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 2189 struct tcmsg *tcm, struct netlink_callback *cb, 2190 int *t_p, int s_t, bool recur) 2191 { 2192 struct Qdisc *q; 2193 int b; 2194 2195 if (!root) 2196 return 0; 2197 2198 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 2199 return -1; 2200 2201 if (!qdisc_dev(root) || !recur) 2202 return 0; 2203 2204 if (tcm->tcm_parent) { 2205 q = qdisc_match_from_root(root, TC_H_MAJ(tcm->tcm_parent)); 2206 if (q && q != root && 2207 tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2208 return -1; 2209 return 0; 2210 } 2211 hash_for_each(qdisc_dev(root)->qdisc_hash, b, q, hash) { 2212 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 2213 return -1; 2214 } 2215 2216 return 0; 2217 } 2218 2219 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 2220 { 2221 struct tcmsg *tcm = nlmsg_data(cb->nlh); 2222 struct net *net = sock_net(skb->sk); 2223 struct netdev_queue *dev_queue; 2224 struct net_device *dev; 2225 int t, s_t; 2226 2227 if (nlmsg_len(cb->nlh) < sizeof(*tcm)) 2228 return 0; 2229 dev = dev_get_by_index(net, tcm->tcm_ifindex); 2230 if (!dev) 2231 return 0; 2232 2233 s_t = cb->args[0]; 2234 t = 0; 2235 2236 if (tc_dump_tclass_root(rtnl_dereference(dev->qdisc), 2237 skb, tcm, cb, &t, s_t, true) < 0) 2238 goto done; 2239 2240 dev_queue = dev_ingress_queue(dev); 2241 if (dev_queue && 2242 tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, 2243 &t, s_t, false) < 0) 2244 goto done; 2245 2246 done: 2247 cb->args[0] = t; 2248 2249 dev_put(dev); 2250 return skb->len; 2251 } 2252 2253 #ifdef CONFIG_PROC_FS 2254 static int psched_show(struct seq_file *seq, void *v) 2255 { 2256 seq_printf(seq, "%08x %08x %08x %08x\n", 2257 (u32)NSEC_PER_USEC, (u32)PSCHED_TICKS2NS(1), 2258 1000000, 2259 (u32)NSEC_PER_SEC / hrtimer_resolution); 2260 2261 return 0; 2262 } 2263 2264 static int __net_init psched_net_init(struct net *net) 2265 { 2266 struct proc_dir_entry *e; 2267 2268 e = proc_create_single("psched", 0, net->proc_net, psched_show); 2269 if (e == NULL) 2270 return -ENOMEM; 2271 2272 return 0; 2273 } 2274 2275 static void __net_exit psched_net_exit(struct net *net) 2276 { 2277 remove_proc_entry("psched", net->proc_net); 2278 } 2279 #else 2280 static int __net_init psched_net_init(struct net *net) 2281 { 2282 return 0; 2283 } 2284 2285 static void __net_exit psched_net_exit(struct net *net) 2286 { 2287 } 2288 #endif 2289 2290 static struct pernet_operations psched_net_ops = { 2291 .init = psched_net_init, 2292 .exit = psched_net_exit, 2293 }; 2294 2295 DEFINE_STATIC_KEY_FALSE(tc_skip_wrapper); 2296 2297 static int __init pktsched_init(void) 2298 { 2299 int err; 2300 2301 err = register_pernet_subsys(&psched_net_ops); 2302 if (err) { 2303 pr_err("pktsched_init: " 2304 "cannot initialize per netns operations\n"); 2305 return err; 2306 } 2307 2308 register_qdisc(&pfifo_fast_ops); 2309 register_qdisc(&pfifo_qdisc_ops); 2310 register_qdisc(&bfifo_qdisc_ops); 2311 register_qdisc(&pfifo_head_drop_qdisc_ops); 2312 register_qdisc(&mq_qdisc_ops); 2313 register_qdisc(&noqueue_qdisc_ops); 2314 2315 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, 0); 2316 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, 0); 2317 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc, 2318 0); 2319 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL, 0); 2320 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL, 0); 2321 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass, 2322 0); 2323 2324 tc_wrapper_init(); 2325 2326 return 0; 2327 } 2328 2329 subsys_initcall(pktsched_init); 2330