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