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