1 /* 2 * net/sched/sch_api.c Packet scheduler API. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 * Fixes: 12 * 13 * Rani Assaf <rani@magic.metawire.com> :980802: JIFFIES and CPU clock sources are repaired. 14 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support 15 * Jamal Hadi Salim <hadi@nortelnetworks.com>: 990601: ingress support 16 */ 17 18 #include <linux/module.h> 19 #include <linux/types.h> 20 #include <linux/kernel.h> 21 #include <linux/string.h> 22 #include <linux/errno.h> 23 #include <linux/skbuff.h> 24 #include <linux/init.h> 25 #include <linux/proc_fs.h> 26 #include <linux/seq_file.h> 27 #include <linux/kmod.h> 28 #include <linux/list.h> 29 #include <linux/hrtimer.h> 30 #include <linux/lockdep.h> 31 32 #include <net/net_namespace.h> 33 #include <net/sock.h> 34 #include <net/netlink.h> 35 #include <net/pkt_sched.h> 36 37 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, u32 clid, 38 struct Qdisc *old, struct Qdisc *new); 39 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 40 struct Qdisc *q, unsigned long cl, int event); 41 42 /* 43 44 Short review. 45 ------------- 46 47 This file consists of two interrelated parts: 48 49 1. queueing disciplines manager frontend. 50 2. traffic classes manager frontend. 51 52 Generally, queueing discipline ("qdisc") is a black box, 53 which is able to enqueue packets and to dequeue them (when 54 device is ready to send something) in order and at times 55 determined by algorithm hidden in it. 56 57 qdisc's are divided to two categories: 58 - "queues", which have no internal structure visible from outside. 59 - "schedulers", which split all the packets to "traffic classes", 60 using "packet classifiers" (look at cls_api.c) 61 62 In turn, classes may have child qdiscs (as rule, queues) 63 attached to them etc. etc. etc. 64 65 The goal of the routines in this file is to translate 66 information supplied by user in the form of handles 67 to more intelligible for kernel form, to make some sanity 68 checks and part of work, which is common to all qdiscs 69 and to provide rtnetlink notifications. 70 71 All real intelligent work is done inside qdisc modules. 72 73 74 75 Every discipline has two major routines: enqueue and dequeue. 76 77 ---dequeue 78 79 dequeue usually returns a skb to send. It is allowed to return NULL, 80 but it does not mean that queue is empty, it just means that 81 discipline does not want to send anything this time. 82 Queue is really empty if q->q.qlen == 0. 83 For complicated disciplines with multiple queues q->q is not 84 real packet queue, but however q->q.qlen must be valid. 85 86 ---enqueue 87 88 enqueue returns 0, if packet was enqueued successfully. 89 If packet (this one or another one) was dropped, it returns 90 not zero error code. 91 NET_XMIT_DROP - this packet dropped 92 Expected action: do not backoff, but wait until queue will clear. 93 NET_XMIT_CN - probably this packet enqueued, but another one dropped. 94 Expected action: backoff or ignore 95 NET_XMIT_POLICED - dropped by police. 96 Expected action: backoff or error to real-time apps. 97 98 Auxiliary routines: 99 100 ---requeue 101 102 requeues once dequeued packet. It is used for non-standard or 103 just buggy devices, which can defer output even if netif_queue_stopped()=0. 104 105 ---reset 106 107 returns qdisc to initial state: purge all buffers, clear all 108 timers, counters (except for statistics) etc. 109 110 ---init 111 112 initializes newly created qdisc. 113 114 ---destroy 115 116 destroys resources allocated by init and during lifetime of qdisc. 117 118 ---change 119 120 changes qdisc parameters. 121 */ 122 123 /* Protects list of registered TC modules. It is pure SMP lock. */ 124 static DEFINE_RWLOCK(qdisc_mod_lock); 125 126 127 /************************************************ 128 * Queueing disciplines manipulation. * 129 ************************************************/ 130 131 132 /* The list of all installed queueing disciplines. */ 133 134 static struct Qdisc_ops *qdisc_base; 135 136 /* Register/uregister queueing discipline */ 137 138 int register_qdisc(struct Qdisc_ops *qops) 139 { 140 struct Qdisc_ops *q, **qp; 141 int rc = -EEXIST; 142 143 write_lock(&qdisc_mod_lock); 144 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 145 if (!strcmp(qops->id, q->id)) 146 goto out; 147 148 if (qops->enqueue == NULL) 149 qops->enqueue = noop_qdisc_ops.enqueue; 150 if (qops->requeue == NULL) 151 qops->requeue = noop_qdisc_ops.requeue; 152 if (qops->dequeue == NULL) 153 qops->dequeue = noop_qdisc_ops.dequeue; 154 155 qops->next = NULL; 156 *qp = qops; 157 rc = 0; 158 out: 159 write_unlock(&qdisc_mod_lock); 160 return rc; 161 } 162 EXPORT_SYMBOL(register_qdisc); 163 164 int unregister_qdisc(struct Qdisc_ops *qops) 165 { 166 struct Qdisc_ops *q, **qp; 167 int err = -ENOENT; 168 169 write_lock(&qdisc_mod_lock); 170 for (qp = &qdisc_base; (q=*qp)!=NULL; qp = &q->next) 171 if (q == qops) 172 break; 173 if (q) { 174 *qp = q->next; 175 q->next = NULL; 176 err = 0; 177 } 178 write_unlock(&qdisc_mod_lock); 179 return err; 180 } 181 EXPORT_SYMBOL(unregister_qdisc); 182 183 /* We know handle. Find qdisc among all qdisc's attached to device 184 (root qdisc, all its children, children of children etc.) 185 */ 186 187 struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 188 { 189 struct Qdisc *q; 190 191 if (!(root->flags & TCQ_F_BUILTIN) && 192 root->handle == handle) 193 return root; 194 195 list_for_each_entry(q, &root->list, list) { 196 if (q->handle == handle) 197 return q; 198 } 199 return NULL; 200 } 201 202 /* 203 * This lock is needed until some qdiscs stop calling qdisc_tree_decrease_qlen() 204 * without rtnl_lock(); currently hfsc_dequeue(), netem_dequeue(), tbf_dequeue() 205 */ 206 static DEFINE_SPINLOCK(qdisc_list_lock); 207 208 static void qdisc_list_add(struct Qdisc *q) 209 { 210 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 211 spin_lock_bh(&qdisc_list_lock); 212 list_add_tail(&q->list, &qdisc_root_sleeping(q)->list); 213 spin_unlock_bh(&qdisc_list_lock); 214 } 215 } 216 217 void qdisc_list_del(struct Qdisc *q) 218 { 219 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) { 220 spin_lock_bh(&qdisc_list_lock); 221 list_del(&q->list); 222 spin_unlock_bh(&qdisc_list_lock); 223 } 224 } 225 EXPORT_SYMBOL(qdisc_list_del); 226 227 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 228 { 229 unsigned int i; 230 struct Qdisc *q; 231 232 spin_lock_bh(&qdisc_list_lock); 233 234 for (i = 0; i < dev->num_tx_queues; i++) { 235 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 236 struct Qdisc *txq_root = txq->qdisc_sleeping; 237 238 q = qdisc_match_from_root(txq_root, handle); 239 if (q) 240 goto unlock; 241 } 242 243 q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle); 244 245 unlock: 246 spin_unlock_bh(&qdisc_list_lock); 247 248 return q; 249 } 250 251 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 252 { 253 unsigned long cl; 254 struct Qdisc *leaf; 255 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 256 257 if (cops == NULL) 258 return NULL; 259 cl = cops->get(p, classid); 260 261 if (cl == 0) 262 return NULL; 263 leaf = cops->leaf(p, cl); 264 cops->put(p, cl); 265 return leaf; 266 } 267 268 /* Find queueing discipline by name */ 269 270 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 271 { 272 struct Qdisc_ops *q = NULL; 273 274 if (kind) { 275 read_lock(&qdisc_mod_lock); 276 for (q = qdisc_base; q; q = q->next) { 277 if (nla_strcmp(kind, q->id) == 0) { 278 if (!try_module_get(q->owner)) 279 q = NULL; 280 break; 281 } 282 } 283 read_unlock(&qdisc_mod_lock); 284 } 285 return q; 286 } 287 288 static struct qdisc_rate_table *qdisc_rtab_list; 289 290 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab) 291 { 292 struct qdisc_rate_table *rtab; 293 294 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 295 if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) { 296 rtab->refcnt++; 297 return rtab; 298 } 299 } 300 301 if (tab == NULL || r->rate == 0 || r->cell_log == 0 || 302 nla_len(tab) != TC_RTAB_SIZE) 303 return NULL; 304 305 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 306 if (rtab) { 307 rtab->rate = *r; 308 rtab->refcnt = 1; 309 memcpy(rtab->data, nla_data(tab), 1024); 310 rtab->next = qdisc_rtab_list; 311 qdisc_rtab_list = rtab; 312 } 313 return rtab; 314 } 315 EXPORT_SYMBOL(qdisc_get_rtab); 316 317 void qdisc_put_rtab(struct qdisc_rate_table *tab) 318 { 319 struct qdisc_rate_table *rtab, **rtabp; 320 321 if (!tab || --tab->refcnt) 322 return; 323 324 for (rtabp = &qdisc_rtab_list; (rtab=*rtabp) != NULL; rtabp = &rtab->next) { 325 if (rtab == tab) { 326 *rtabp = rtab->next; 327 kfree(rtab); 328 return; 329 } 330 } 331 } 332 EXPORT_SYMBOL(qdisc_put_rtab); 333 334 static LIST_HEAD(qdisc_stab_list); 335 static DEFINE_SPINLOCK(qdisc_stab_lock); 336 337 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 338 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 339 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 340 }; 341 342 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt) 343 { 344 struct nlattr *tb[TCA_STAB_MAX + 1]; 345 struct qdisc_size_table *stab; 346 struct tc_sizespec *s; 347 unsigned int tsize = 0; 348 u16 *tab = NULL; 349 int err; 350 351 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy); 352 if (err < 0) 353 return ERR_PTR(err); 354 if (!tb[TCA_STAB_BASE]) 355 return ERR_PTR(-EINVAL); 356 357 s = nla_data(tb[TCA_STAB_BASE]); 358 359 if (s->tsize > 0) { 360 if (!tb[TCA_STAB_DATA]) 361 return ERR_PTR(-EINVAL); 362 tab = nla_data(tb[TCA_STAB_DATA]); 363 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 364 } 365 366 if (!s || tsize != s->tsize || (!tab && tsize > 0)) 367 return ERR_PTR(-EINVAL); 368 369 spin_lock(&qdisc_stab_lock); 370 371 list_for_each_entry(stab, &qdisc_stab_list, list) { 372 if (memcmp(&stab->szopts, s, sizeof(*s))) 373 continue; 374 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16))) 375 continue; 376 stab->refcnt++; 377 spin_unlock(&qdisc_stab_lock); 378 return stab; 379 } 380 381 spin_unlock(&qdisc_stab_lock); 382 383 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); 384 if (!stab) 385 return ERR_PTR(-ENOMEM); 386 387 stab->refcnt = 1; 388 stab->szopts = *s; 389 if (tsize > 0) 390 memcpy(stab->data, tab, tsize * sizeof(u16)); 391 392 spin_lock(&qdisc_stab_lock); 393 list_add_tail(&stab->list, &qdisc_stab_list); 394 spin_unlock(&qdisc_stab_lock); 395 396 return stab; 397 } 398 399 void qdisc_put_stab(struct qdisc_size_table *tab) 400 { 401 if (!tab) 402 return; 403 404 spin_lock(&qdisc_stab_lock); 405 406 if (--tab->refcnt == 0) { 407 list_del(&tab->list); 408 kfree(tab); 409 } 410 411 spin_unlock(&qdisc_stab_lock); 412 } 413 EXPORT_SYMBOL(qdisc_put_stab); 414 415 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 416 { 417 struct nlattr *nest; 418 419 nest = nla_nest_start(skb, TCA_STAB); 420 NLA_PUT(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts); 421 nla_nest_end(skb, nest); 422 423 return skb->len; 424 425 nla_put_failure: 426 return -1; 427 } 428 429 void qdisc_calculate_pkt_len(struct sk_buff *skb, struct qdisc_size_table *stab) 430 { 431 int pkt_len, slot; 432 433 pkt_len = skb->len + stab->szopts.overhead; 434 if (unlikely(!stab->szopts.tsize)) 435 goto out; 436 437 slot = pkt_len + stab->szopts.cell_align; 438 if (unlikely(slot < 0)) 439 slot = 0; 440 441 slot >>= stab->szopts.cell_log; 442 if (likely(slot < stab->szopts.tsize)) 443 pkt_len = stab->data[slot]; 444 else 445 pkt_len = stab->data[stab->szopts.tsize - 1] * 446 (slot / stab->szopts.tsize) + 447 stab->data[slot % stab->szopts.tsize]; 448 449 pkt_len <<= stab->szopts.size_log; 450 out: 451 if (unlikely(pkt_len < 1)) 452 pkt_len = 1; 453 qdisc_skb_cb(skb)->pkt_len = pkt_len; 454 } 455 EXPORT_SYMBOL(qdisc_calculate_pkt_len); 456 457 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 458 { 459 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 460 timer); 461 462 wd->qdisc->flags &= ~TCQ_F_THROTTLED; 463 smp_wmb(); 464 __netif_schedule(qdisc_root(wd->qdisc)); 465 466 return HRTIMER_NORESTART; 467 } 468 469 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc) 470 { 471 hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 472 wd->timer.function = qdisc_watchdog; 473 wd->qdisc = qdisc; 474 } 475 EXPORT_SYMBOL(qdisc_watchdog_init); 476 477 void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires) 478 { 479 ktime_t time; 480 481 if (test_bit(__QDISC_STATE_DEACTIVATED, 482 &qdisc_root_sleeping(wd->qdisc)->state)) 483 return; 484 485 wd->qdisc->flags |= TCQ_F_THROTTLED; 486 time = ktime_set(0, 0); 487 time = ktime_add_ns(time, PSCHED_US2NS(expires)); 488 hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS); 489 } 490 EXPORT_SYMBOL(qdisc_watchdog_schedule); 491 492 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd) 493 { 494 hrtimer_cancel(&wd->timer); 495 wd->qdisc->flags &= ~TCQ_F_THROTTLED; 496 } 497 EXPORT_SYMBOL(qdisc_watchdog_cancel); 498 499 static struct hlist_head *qdisc_class_hash_alloc(unsigned int n) 500 { 501 unsigned int size = n * sizeof(struct hlist_head), i; 502 struct hlist_head *h; 503 504 if (size <= PAGE_SIZE) 505 h = kmalloc(size, GFP_KERNEL); 506 else 507 h = (struct hlist_head *) 508 __get_free_pages(GFP_KERNEL, get_order(size)); 509 510 if (h != NULL) { 511 for (i = 0; i < n; i++) 512 INIT_HLIST_HEAD(&h[i]); 513 } 514 return h; 515 } 516 517 static void qdisc_class_hash_free(struct hlist_head *h, unsigned int n) 518 { 519 unsigned int size = n * sizeof(struct hlist_head); 520 521 if (size <= PAGE_SIZE) 522 kfree(h); 523 else 524 free_pages((unsigned long)h, get_order(size)); 525 } 526 527 void qdisc_class_hash_grow(struct Qdisc *sch, struct Qdisc_class_hash *clhash) 528 { 529 struct Qdisc_class_common *cl; 530 struct hlist_node *n, *next; 531 struct hlist_head *nhash, *ohash; 532 unsigned int nsize, nmask, osize; 533 unsigned int i, h; 534 535 /* Rehash when load factor exceeds 0.75 */ 536 if (clhash->hashelems * 4 <= clhash->hashsize * 3) 537 return; 538 nsize = clhash->hashsize * 2; 539 nmask = nsize - 1; 540 nhash = qdisc_class_hash_alloc(nsize); 541 if (nhash == NULL) 542 return; 543 544 ohash = clhash->hash; 545 osize = clhash->hashsize; 546 547 sch_tree_lock(sch); 548 for (i = 0; i < osize; i++) { 549 hlist_for_each_entry_safe(cl, n, next, &ohash[i], hnode) { 550 h = qdisc_class_hash(cl->classid, nmask); 551 hlist_add_head(&cl->hnode, &nhash[h]); 552 } 553 } 554 clhash->hash = nhash; 555 clhash->hashsize = nsize; 556 clhash->hashmask = nmask; 557 sch_tree_unlock(sch); 558 559 qdisc_class_hash_free(ohash, osize); 560 } 561 EXPORT_SYMBOL(qdisc_class_hash_grow); 562 563 int qdisc_class_hash_init(struct Qdisc_class_hash *clhash) 564 { 565 unsigned int size = 4; 566 567 clhash->hash = qdisc_class_hash_alloc(size); 568 if (clhash->hash == NULL) 569 return -ENOMEM; 570 clhash->hashsize = size; 571 clhash->hashmask = size - 1; 572 clhash->hashelems = 0; 573 return 0; 574 } 575 EXPORT_SYMBOL(qdisc_class_hash_init); 576 577 void qdisc_class_hash_destroy(struct Qdisc_class_hash *clhash) 578 { 579 qdisc_class_hash_free(clhash->hash, clhash->hashsize); 580 } 581 EXPORT_SYMBOL(qdisc_class_hash_destroy); 582 583 void qdisc_class_hash_insert(struct Qdisc_class_hash *clhash, 584 struct Qdisc_class_common *cl) 585 { 586 unsigned int h; 587 588 INIT_HLIST_NODE(&cl->hnode); 589 h = qdisc_class_hash(cl->classid, clhash->hashmask); 590 hlist_add_head(&cl->hnode, &clhash->hash[h]); 591 clhash->hashelems++; 592 } 593 EXPORT_SYMBOL(qdisc_class_hash_insert); 594 595 void qdisc_class_hash_remove(struct Qdisc_class_hash *clhash, 596 struct Qdisc_class_common *cl) 597 { 598 hlist_del(&cl->hnode); 599 clhash->hashelems--; 600 } 601 EXPORT_SYMBOL(qdisc_class_hash_remove); 602 603 /* Allocate an unique handle from space managed by kernel */ 604 605 static u32 qdisc_alloc_handle(struct net_device *dev) 606 { 607 int i = 0x10000; 608 static u32 autohandle = TC_H_MAKE(0x80000000U, 0); 609 610 do { 611 autohandle += TC_H_MAKE(0x10000U, 0); 612 if (autohandle == TC_H_MAKE(TC_H_ROOT, 0)) 613 autohandle = TC_H_MAKE(0x80000000U, 0); 614 } while (qdisc_lookup(dev, autohandle) && --i > 0); 615 616 return i>0 ? autohandle : 0; 617 } 618 619 /* Attach toplevel qdisc to device queue. */ 620 621 static struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, 622 struct Qdisc *qdisc) 623 { 624 struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; 625 spinlock_t *root_lock; 626 627 root_lock = qdisc_lock(oqdisc); 628 spin_lock_bh(root_lock); 629 630 /* Prune old scheduler */ 631 if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) 632 qdisc_reset(oqdisc); 633 634 /* ... and graft new one */ 635 if (qdisc == NULL) 636 qdisc = &noop_qdisc; 637 dev_queue->qdisc_sleeping = qdisc; 638 rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); 639 640 spin_unlock_bh(root_lock); 641 642 return oqdisc; 643 } 644 645 void qdisc_tree_decrease_qlen(struct Qdisc *sch, unsigned int n) 646 { 647 const struct Qdisc_class_ops *cops; 648 unsigned long cl; 649 u32 parentid; 650 651 if (n == 0) 652 return; 653 while ((parentid = sch->parent)) { 654 if (TC_H_MAJ(parentid) == TC_H_MAJ(TC_H_INGRESS)) 655 return; 656 657 sch = qdisc_lookup(qdisc_dev(sch), TC_H_MAJ(parentid)); 658 if (sch == NULL) { 659 WARN_ON(parentid != TC_H_ROOT); 660 return; 661 } 662 cops = sch->ops->cl_ops; 663 if (cops->qlen_notify) { 664 cl = cops->get(sch, parentid); 665 cops->qlen_notify(sch, cl); 666 cops->put(sch, cl); 667 } 668 sch->q.qlen -= n; 669 } 670 } 671 EXPORT_SYMBOL(qdisc_tree_decrease_qlen); 672 673 static void notify_and_destroy(struct sk_buff *skb, struct nlmsghdr *n, u32 clid, 674 struct Qdisc *old, struct Qdisc *new) 675 { 676 if (new || old) 677 qdisc_notify(skb, n, clid, old, new); 678 679 if (old) 680 qdisc_destroy(old); 681 } 682 683 /* Graft qdisc "new" to class "classid" of qdisc "parent" or 684 * to device "dev". 685 * 686 * When appropriate send a netlink notification using 'skb' 687 * and "n". 688 * 689 * On success, destroy old qdisc. 690 */ 691 692 static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, 693 struct sk_buff *skb, struct nlmsghdr *n, u32 classid, 694 struct Qdisc *new, struct Qdisc *old) 695 { 696 struct Qdisc *q = old; 697 int err = 0; 698 699 if (parent == NULL) { 700 unsigned int i, num_q, ingress; 701 702 ingress = 0; 703 num_q = dev->num_tx_queues; 704 if ((q && q->flags & TCQ_F_INGRESS) || 705 (new && new->flags & TCQ_F_INGRESS)) { 706 num_q = 1; 707 ingress = 1; 708 } 709 710 if (dev->flags & IFF_UP) 711 dev_deactivate(dev); 712 713 for (i = 0; i < num_q; i++) { 714 struct netdev_queue *dev_queue = &dev->rx_queue; 715 716 if (!ingress) 717 dev_queue = netdev_get_tx_queue(dev, i); 718 719 old = dev_graft_qdisc(dev_queue, new); 720 if (new && i > 0) 721 atomic_inc(&new->refcnt); 722 723 notify_and_destroy(skb, n, classid, old, new); 724 } 725 726 if (dev->flags & IFF_UP) 727 dev_activate(dev); 728 } else { 729 const struct Qdisc_class_ops *cops = parent->ops->cl_ops; 730 731 err = -EINVAL; 732 733 if (cops) { 734 unsigned long cl = cops->get(parent, classid); 735 if (cl) { 736 err = cops->graft(parent, cl, new, &old); 737 cops->put(parent, cl); 738 } 739 } 740 if (!err) 741 notify_and_destroy(skb, n, classid, old, new); 742 } 743 return err; 744 } 745 746 /* lockdep annotation is needed for ingress; egress gets it only for name */ 747 static struct lock_class_key qdisc_tx_lock; 748 static struct lock_class_key qdisc_rx_lock; 749 750 /* 751 Allocate and initialize new qdisc. 752 753 Parameters are passed via opt. 754 */ 755 756 static struct Qdisc * 757 qdisc_create(struct net_device *dev, struct netdev_queue *dev_queue, 758 u32 parent, u32 handle, struct nlattr **tca, int *errp) 759 { 760 int err; 761 struct nlattr *kind = tca[TCA_KIND]; 762 struct Qdisc *sch; 763 struct Qdisc_ops *ops; 764 struct qdisc_size_table *stab; 765 766 ops = qdisc_lookup_ops(kind); 767 #ifdef CONFIG_MODULES 768 if (ops == NULL && kind != NULL) { 769 char name[IFNAMSIZ]; 770 if (nla_strlcpy(name, kind, IFNAMSIZ) < IFNAMSIZ) { 771 /* We dropped the RTNL semaphore in order to 772 * perform the module load. So, even if we 773 * succeeded in loading the module we have to 774 * tell the caller to replay the request. We 775 * indicate this using -EAGAIN. 776 * We replay the request because the device may 777 * go away in the mean time. 778 */ 779 rtnl_unlock(); 780 request_module("sch_%s", name); 781 rtnl_lock(); 782 ops = qdisc_lookup_ops(kind); 783 if (ops != NULL) { 784 /* We will try again qdisc_lookup_ops, 785 * so don't keep a reference. 786 */ 787 module_put(ops->owner); 788 err = -EAGAIN; 789 goto err_out; 790 } 791 } 792 } 793 #endif 794 795 err = -ENOENT; 796 if (ops == NULL) 797 goto err_out; 798 799 sch = qdisc_alloc(dev_queue, ops); 800 if (IS_ERR(sch)) { 801 err = PTR_ERR(sch); 802 goto err_out2; 803 } 804 805 sch->parent = parent; 806 807 if (handle == TC_H_INGRESS) { 808 sch->flags |= TCQ_F_INGRESS; 809 handle = TC_H_MAKE(TC_H_INGRESS, 0); 810 lockdep_set_class(qdisc_lock(sch), &qdisc_rx_lock); 811 } else { 812 if (handle == 0) { 813 handle = qdisc_alloc_handle(dev); 814 err = -ENOMEM; 815 if (handle == 0) 816 goto err_out3; 817 } 818 lockdep_set_class(qdisc_lock(sch), &qdisc_tx_lock); 819 } 820 821 sch->handle = handle; 822 823 if (!ops->init || (err = ops->init(sch, tca[TCA_OPTIONS])) == 0) { 824 if (tca[TCA_STAB]) { 825 stab = qdisc_get_stab(tca[TCA_STAB]); 826 if (IS_ERR(stab)) { 827 err = PTR_ERR(stab); 828 goto err_out3; 829 } 830 sch->stab = stab; 831 } 832 if (tca[TCA_RATE]) { 833 spinlock_t *root_lock; 834 835 if ((sch->parent != TC_H_ROOT) && 836 !(sch->flags & TCQ_F_INGRESS)) 837 root_lock = qdisc_root_sleeping_lock(sch); 838 else 839 root_lock = qdisc_lock(sch); 840 841 err = gen_new_estimator(&sch->bstats, &sch->rate_est, 842 root_lock, tca[TCA_RATE]); 843 if (err) { 844 /* 845 * Any broken qdiscs that would require 846 * a ops->reset() here? The qdisc was never 847 * in action so it shouldn't be necessary. 848 */ 849 if (ops->destroy) 850 ops->destroy(sch); 851 goto err_out3; 852 } 853 } 854 855 qdisc_list_add(sch); 856 857 return sch; 858 } 859 err_out3: 860 qdisc_put_stab(sch->stab); 861 dev_put(dev); 862 kfree((char *) sch - sch->padded); 863 err_out2: 864 module_put(ops->owner); 865 err_out: 866 *errp = err; 867 return NULL; 868 } 869 870 static int qdisc_change(struct Qdisc *sch, struct nlattr **tca) 871 { 872 struct qdisc_size_table *stab = NULL; 873 int err = 0; 874 875 if (tca[TCA_OPTIONS]) { 876 if (sch->ops->change == NULL) 877 return -EINVAL; 878 err = sch->ops->change(sch, tca[TCA_OPTIONS]); 879 if (err) 880 return err; 881 } 882 883 if (tca[TCA_STAB]) { 884 stab = qdisc_get_stab(tca[TCA_STAB]); 885 if (IS_ERR(stab)) 886 return PTR_ERR(stab); 887 } 888 889 qdisc_put_stab(sch->stab); 890 sch->stab = stab; 891 892 if (tca[TCA_RATE]) 893 gen_replace_estimator(&sch->bstats, &sch->rate_est, 894 qdisc_root_sleeping_lock(sch), 895 tca[TCA_RATE]); 896 return 0; 897 } 898 899 struct check_loop_arg 900 { 901 struct qdisc_walker w; 902 struct Qdisc *p; 903 int depth; 904 }; 905 906 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w); 907 908 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 909 { 910 struct check_loop_arg arg; 911 912 if (q->ops->cl_ops == NULL) 913 return 0; 914 915 arg.w.stop = arg.w.skip = arg.w.count = 0; 916 arg.w.fn = check_loop_fn; 917 arg.depth = depth; 918 arg.p = p; 919 q->ops->cl_ops->walk(q, &arg.w); 920 return arg.w.stop ? -ELOOP : 0; 921 } 922 923 static int 924 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 925 { 926 struct Qdisc *leaf; 927 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 928 struct check_loop_arg *arg = (struct check_loop_arg *)w; 929 930 leaf = cops->leaf(q, cl); 931 if (leaf) { 932 if (leaf == arg->p || arg->depth > 7) 933 return -ELOOP; 934 return check_loop(leaf, arg->p, arg->depth + 1); 935 } 936 return 0; 937 } 938 939 /* 940 * Delete/get qdisc. 941 */ 942 943 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 944 { 945 struct net *net = sock_net(skb->sk); 946 struct tcmsg *tcm = NLMSG_DATA(n); 947 struct nlattr *tca[TCA_MAX + 1]; 948 struct net_device *dev; 949 u32 clid = tcm->tcm_parent; 950 struct Qdisc *q = NULL; 951 struct Qdisc *p = NULL; 952 int err; 953 954 if (net != &init_net) 955 return -EINVAL; 956 957 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 958 return -ENODEV; 959 960 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 961 if (err < 0) 962 return err; 963 964 if (clid) { 965 if (clid != TC_H_ROOT) { 966 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 967 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 968 return -ENOENT; 969 q = qdisc_leaf(p, clid); 970 } else { /* ingress */ 971 q = dev->rx_queue.qdisc_sleeping; 972 } 973 } else { 974 struct netdev_queue *dev_queue; 975 dev_queue = netdev_get_tx_queue(dev, 0); 976 q = dev_queue->qdisc_sleeping; 977 } 978 if (!q) 979 return -ENOENT; 980 981 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) 982 return -EINVAL; 983 } else { 984 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 985 return -ENOENT; 986 } 987 988 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 989 return -EINVAL; 990 991 if (n->nlmsg_type == RTM_DELQDISC) { 992 if (!clid) 993 return -EINVAL; 994 if (q->handle == 0) 995 return -ENOENT; 996 if ((err = qdisc_graft(dev, p, skb, n, clid, NULL, q)) != 0) 997 return err; 998 } else { 999 qdisc_notify(skb, n, clid, NULL, q); 1000 } 1001 return 0; 1002 } 1003 1004 /* 1005 Create/change qdisc. 1006 */ 1007 1008 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1009 { 1010 struct net *net = sock_net(skb->sk); 1011 struct tcmsg *tcm; 1012 struct nlattr *tca[TCA_MAX + 1]; 1013 struct net_device *dev; 1014 u32 clid; 1015 struct Qdisc *q, *p; 1016 int err; 1017 1018 if (net != &init_net) 1019 return -EINVAL; 1020 1021 replay: 1022 /* Reinit, just in case something touches this. */ 1023 tcm = NLMSG_DATA(n); 1024 clid = tcm->tcm_parent; 1025 q = p = NULL; 1026 1027 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1028 return -ENODEV; 1029 1030 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1031 if (err < 0) 1032 return err; 1033 1034 if (clid) { 1035 if (clid != TC_H_ROOT) { 1036 if (clid != TC_H_INGRESS) { 1037 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 1038 return -ENOENT; 1039 q = qdisc_leaf(p, clid); 1040 } else { /*ingress */ 1041 q = dev->rx_queue.qdisc_sleeping; 1042 } 1043 } else { 1044 struct netdev_queue *dev_queue; 1045 dev_queue = netdev_get_tx_queue(dev, 0); 1046 q = dev_queue->qdisc_sleeping; 1047 } 1048 1049 /* It may be default qdisc, ignore it */ 1050 if (q && q->handle == 0) 1051 q = NULL; 1052 1053 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1054 if (tcm->tcm_handle) { 1055 if (q && !(n->nlmsg_flags&NLM_F_REPLACE)) 1056 return -EEXIST; 1057 if (TC_H_MIN(tcm->tcm_handle)) 1058 return -EINVAL; 1059 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 1060 goto create_n_graft; 1061 if (n->nlmsg_flags&NLM_F_EXCL) 1062 return -EEXIST; 1063 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1064 return -EINVAL; 1065 if (q == p || 1066 (p && check_loop(q, p, 0))) 1067 return -ELOOP; 1068 atomic_inc(&q->refcnt); 1069 goto graft; 1070 } else { 1071 if (q == NULL) 1072 goto create_n_graft; 1073 1074 /* This magic test requires explanation. 1075 * 1076 * We know, that some child q is already 1077 * attached to this parent and have choice: 1078 * either to change it or to create/graft new one. 1079 * 1080 * 1. We are allowed to create/graft only 1081 * if CREATE and REPLACE flags are set. 1082 * 1083 * 2. If EXCL is set, requestor wanted to say, 1084 * that qdisc tcm_handle is not expected 1085 * to exist, so that we choose create/graft too. 1086 * 1087 * 3. The last case is when no flags are set. 1088 * Alas, it is sort of hole in API, we 1089 * cannot decide what to do unambiguously. 1090 * For now we select create/graft, if 1091 * user gave KIND, which does not match existing. 1092 */ 1093 if ((n->nlmsg_flags&NLM_F_CREATE) && 1094 (n->nlmsg_flags&NLM_F_REPLACE) && 1095 ((n->nlmsg_flags&NLM_F_EXCL) || 1096 (tca[TCA_KIND] && 1097 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1098 goto create_n_graft; 1099 } 1100 } 1101 } else { 1102 if (!tcm->tcm_handle) 1103 return -EINVAL; 1104 q = qdisc_lookup(dev, tcm->tcm_handle); 1105 } 1106 1107 /* Change qdisc parameters */ 1108 if (q == NULL) 1109 return -ENOENT; 1110 if (n->nlmsg_flags&NLM_F_EXCL) 1111 return -EEXIST; 1112 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1113 return -EINVAL; 1114 err = qdisc_change(q, tca); 1115 if (err == 0) 1116 qdisc_notify(skb, n, clid, NULL, q); 1117 return err; 1118 1119 create_n_graft: 1120 if (!(n->nlmsg_flags&NLM_F_CREATE)) 1121 return -ENOENT; 1122 if (clid == TC_H_INGRESS) 1123 q = qdisc_create(dev, &dev->rx_queue, 1124 tcm->tcm_parent, tcm->tcm_parent, 1125 tca, &err); 1126 else 1127 q = qdisc_create(dev, netdev_get_tx_queue(dev, 0), 1128 tcm->tcm_parent, tcm->tcm_handle, 1129 tca, &err); 1130 if (q == NULL) { 1131 if (err == -EAGAIN) 1132 goto replay; 1133 return err; 1134 } 1135 1136 graft: 1137 err = qdisc_graft(dev, p, skb, n, clid, q, NULL); 1138 if (err) { 1139 if (q) 1140 qdisc_destroy(q); 1141 return err; 1142 } 1143 1144 return 0; 1145 } 1146 1147 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 1148 u32 pid, u32 seq, u16 flags, int event) 1149 { 1150 struct tcmsg *tcm; 1151 struct nlmsghdr *nlh; 1152 unsigned char *b = skb_tail_pointer(skb); 1153 struct gnet_dump d; 1154 1155 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1156 tcm = NLMSG_DATA(nlh); 1157 tcm->tcm_family = AF_UNSPEC; 1158 tcm->tcm__pad1 = 0; 1159 tcm->tcm__pad2 = 0; 1160 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1161 tcm->tcm_parent = clid; 1162 tcm->tcm_handle = q->handle; 1163 tcm->tcm_info = atomic_read(&q->refcnt); 1164 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1165 if (q->ops->dump && q->ops->dump(q, skb) < 0) 1166 goto nla_put_failure; 1167 q->qstats.qlen = q->q.qlen; 1168 1169 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0) 1170 goto nla_put_failure; 1171 1172 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1173 qdisc_root_sleeping_lock(q), &d) < 0) 1174 goto nla_put_failure; 1175 1176 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 1177 goto nla_put_failure; 1178 1179 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 || 1180 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 1181 gnet_stats_copy_queue(&d, &q->qstats) < 0) 1182 goto nla_put_failure; 1183 1184 if (gnet_stats_finish_copy(&d) < 0) 1185 goto nla_put_failure; 1186 1187 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1188 return skb->len; 1189 1190 nlmsg_failure: 1191 nla_put_failure: 1192 nlmsg_trim(skb, b); 1193 return -1; 1194 } 1195 1196 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1197 u32 clid, struct Qdisc *old, struct Qdisc *new) 1198 { 1199 struct sk_buff *skb; 1200 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1201 1202 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1203 if (!skb) 1204 return -ENOBUFS; 1205 1206 if (old && old->handle) { 1207 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0) 1208 goto err_out; 1209 } 1210 if (new) { 1211 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1212 goto err_out; 1213 } 1214 1215 if (skb->len) 1216 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1217 1218 err_out: 1219 kfree_skb(skb); 1220 return -EINVAL; 1221 } 1222 1223 static bool tc_qdisc_dump_ignore(struct Qdisc *q) 1224 { 1225 return (q->flags & TCQ_F_BUILTIN) ? true : false; 1226 } 1227 1228 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1229 struct netlink_callback *cb, 1230 int *q_idx_p, int s_q_idx) 1231 { 1232 int ret = 0, q_idx = *q_idx_p; 1233 struct Qdisc *q; 1234 1235 if (!root) 1236 return 0; 1237 1238 q = root; 1239 if (q_idx < s_q_idx) { 1240 q_idx++; 1241 } else { 1242 if (!tc_qdisc_dump_ignore(q) && 1243 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1244 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1245 goto done; 1246 q_idx++; 1247 } 1248 list_for_each_entry(q, &root->list, list) { 1249 if (q_idx < s_q_idx) { 1250 q_idx++; 1251 continue; 1252 } 1253 if (!tc_qdisc_dump_ignore(q) && 1254 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1255 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1256 goto done; 1257 q_idx++; 1258 } 1259 1260 out: 1261 *q_idx_p = q_idx; 1262 return ret; 1263 done: 1264 ret = -1; 1265 goto out; 1266 } 1267 1268 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1269 { 1270 struct net *net = sock_net(skb->sk); 1271 int idx, q_idx; 1272 int s_idx, s_q_idx; 1273 struct net_device *dev; 1274 1275 if (net != &init_net) 1276 return 0; 1277 1278 s_idx = cb->args[0]; 1279 s_q_idx = q_idx = cb->args[1]; 1280 read_lock(&dev_base_lock); 1281 idx = 0; 1282 for_each_netdev(&init_net, dev) { 1283 struct netdev_queue *dev_queue; 1284 1285 if (idx < s_idx) 1286 goto cont; 1287 if (idx > s_idx) 1288 s_q_idx = 0; 1289 q_idx = 0; 1290 1291 dev_queue = netdev_get_tx_queue(dev, 0); 1292 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1293 goto done; 1294 1295 dev_queue = &dev->rx_queue; 1296 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1297 goto done; 1298 1299 cont: 1300 idx++; 1301 } 1302 1303 done: 1304 read_unlock(&dev_base_lock); 1305 1306 cb->args[0] = idx; 1307 cb->args[1] = q_idx; 1308 1309 return skb->len; 1310 } 1311 1312 1313 1314 /************************************************ 1315 * Traffic classes manipulation. * 1316 ************************************************/ 1317 1318 1319 1320 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1321 { 1322 struct net *net = sock_net(skb->sk); 1323 struct netdev_queue *dev_queue; 1324 struct tcmsg *tcm = NLMSG_DATA(n); 1325 struct nlattr *tca[TCA_MAX + 1]; 1326 struct net_device *dev; 1327 struct Qdisc *q = NULL; 1328 const struct Qdisc_class_ops *cops; 1329 unsigned long cl = 0; 1330 unsigned long new_cl; 1331 u32 pid = tcm->tcm_parent; 1332 u32 clid = tcm->tcm_handle; 1333 u32 qid = TC_H_MAJ(clid); 1334 int err; 1335 1336 if (net != &init_net) 1337 return -EINVAL; 1338 1339 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1340 return -ENODEV; 1341 1342 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1343 if (err < 0) 1344 return err; 1345 1346 /* 1347 parent == TC_H_UNSPEC - unspecified parent. 1348 parent == TC_H_ROOT - class is root, which has no parent. 1349 parent == X:0 - parent is root class. 1350 parent == X:Y - parent is a node in hierarchy. 1351 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 1352 1353 handle == 0:0 - generate handle from kernel pool. 1354 handle == 0:Y - class is X:Y, where X:0 is qdisc. 1355 handle == X:Y - clear. 1356 handle == X:0 - root class. 1357 */ 1358 1359 /* Step 1. Determine qdisc handle X:0 */ 1360 1361 dev_queue = netdev_get_tx_queue(dev, 0); 1362 if (pid != TC_H_ROOT) { 1363 u32 qid1 = TC_H_MAJ(pid); 1364 1365 if (qid && qid1) { 1366 /* If both majors are known, they must be identical. */ 1367 if (qid != qid1) 1368 return -EINVAL; 1369 } else if (qid1) { 1370 qid = qid1; 1371 } else if (qid == 0) 1372 qid = dev_queue->qdisc_sleeping->handle; 1373 1374 /* Now qid is genuine qdisc handle consistent 1375 both with parent and child. 1376 1377 TC_H_MAJ(pid) still may be unspecified, complete it now. 1378 */ 1379 if (pid) 1380 pid = TC_H_MAKE(qid, pid); 1381 } else { 1382 if (qid == 0) 1383 qid = dev_queue->qdisc_sleeping->handle; 1384 } 1385 1386 /* OK. Locate qdisc */ 1387 if ((q = qdisc_lookup(dev, qid)) == NULL) 1388 return -ENOENT; 1389 1390 /* An check that it supports classes */ 1391 cops = q->ops->cl_ops; 1392 if (cops == NULL) 1393 return -EINVAL; 1394 1395 /* Now try to get class */ 1396 if (clid == 0) { 1397 if (pid == TC_H_ROOT) 1398 clid = qid; 1399 } else 1400 clid = TC_H_MAKE(qid, clid); 1401 1402 if (clid) 1403 cl = cops->get(q, clid); 1404 1405 if (cl == 0) { 1406 err = -ENOENT; 1407 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE)) 1408 goto out; 1409 } else { 1410 switch (n->nlmsg_type) { 1411 case RTM_NEWTCLASS: 1412 err = -EEXIST; 1413 if (n->nlmsg_flags&NLM_F_EXCL) 1414 goto out; 1415 break; 1416 case RTM_DELTCLASS: 1417 err = cops->delete(q, cl); 1418 if (err == 0) 1419 tclass_notify(skb, n, q, cl, RTM_DELTCLASS); 1420 goto out; 1421 case RTM_GETTCLASS: 1422 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS); 1423 goto out; 1424 default: 1425 err = -EINVAL; 1426 goto out; 1427 } 1428 } 1429 1430 new_cl = cl; 1431 err = cops->change(q, clid, pid, tca, &new_cl); 1432 if (err == 0) 1433 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS); 1434 1435 out: 1436 if (cl) 1437 cops->put(q, cl); 1438 1439 return err; 1440 } 1441 1442 1443 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1444 unsigned long cl, 1445 u32 pid, u32 seq, u16 flags, int event) 1446 { 1447 struct tcmsg *tcm; 1448 struct nlmsghdr *nlh; 1449 unsigned char *b = skb_tail_pointer(skb); 1450 struct gnet_dump d; 1451 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1452 1453 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1454 tcm = NLMSG_DATA(nlh); 1455 tcm->tcm_family = AF_UNSPEC; 1456 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1457 tcm->tcm_parent = q->handle; 1458 tcm->tcm_handle = q->handle; 1459 tcm->tcm_info = 0; 1460 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1461 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1462 goto nla_put_failure; 1463 1464 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1465 qdisc_root_sleeping_lock(q), &d) < 0) 1466 goto nla_put_failure; 1467 1468 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1469 goto nla_put_failure; 1470 1471 if (gnet_stats_finish_copy(&d) < 0) 1472 goto nla_put_failure; 1473 1474 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1475 return skb->len; 1476 1477 nlmsg_failure: 1478 nla_put_failure: 1479 nlmsg_trim(skb, b); 1480 return -1; 1481 } 1482 1483 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1484 struct Qdisc *q, unsigned long cl, int event) 1485 { 1486 struct sk_buff *skb; 1487 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1488 1489 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1490 if (!skb) 1491 return -ENOBUFS; 1492 1493 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) { 1494 kfree_skb(skb); 1495 return -EINVAL; 1496 } 1497 1498 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1499 } 1500 1501 struct qdisc_dump_args 1502 { 1503 struct qdisc_walker w; 1504 struct sk_buff *skb; 1505 struct netlink_callback *cb; 1506 }; 1507 1508 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg) 1509 { 1510 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 1511 1512 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid, 1513 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS); 1514 } 1515 1516 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 1517 struct tcmsg *tcm, struct netlink_callback *cb, 1518 int *t_p, int s_t) 1519 { 1520 struct qdisc_dump_args arg; 1521 1522 if (tc_qdisc_dump_ignore(q) || 1523 *t_p < s_t || !q->ops->cl_ops || 1524 (tcm->tcm_parent && 1525 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 1526 (*t_p)++; 1527 return 0; 1528 } 1529 if (*t_p > s_t) 1530 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 1531 arg.w.fn = qdisc_class_dump; 1532 arg.skb = skb; 1533 arg.cb = cb; 1534 arg.w.stop = 0; 1535 arg.w.skip = cb->args[1]; 1536 arg.w.count = 0; 1537 q->ops->cl_ops->walk(q, &arg.w); 1538 cb->args[1] = arg.w.count; 1539 if (arg.w.stop) 1540 return -1; 1541 (*t_p)++; 1542 return 0; 1543 } 1544 1545 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 1546 struct tcmsg *tcm, struct netlink_callback *cb, 1547 int *t_p, int s_t) 1548 { 1549 struct Qdisc *q; 1550 1551 if (!root) 1552 return 0; 1553 1554 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 1555 return -1; 1556 1557 list_for_each_entry(q, &root->list, list) { 1558 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 1559 return -1; 1560 } 1561 1562 return 0; 1563 } 1564 1565 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 1566 { 1567 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh); 1568 struct net *net = sock_net(skb->sk); 1569 struct netdev_queue *dev_queue; 1570 struct net_device *dev; 1571 int t, s_t; 1572 1573 if (net != &init_net) 1574 return 0; 1575 1576 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm))) 1577 return 0; 1578 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1579 return 0; 1580 1581 s_t = cb->args[0]; 1582 t = 0; 1583 1584 dev_queue = netdev_get_tx_queue(dev, 0); 1585 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1586 goto done; 1587 1588 dev_queue = &dev->rx_queue; 1589 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1590 goto done; 1591 1592 done: 1593 cb->args[0] = t; 1594 1595 dev_put(dev); 1596 return skb->len; 1597 } 1598 1599 /* Main classifier routine: scans classifier chain attached 1600 to this qdisc, (optionally) tests for protocol and asks 1601 specific classifiers. 1602 */ 1603 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp, 1604 struct tcf_result *res) 1605 { 1606 __be16 protocol = skb->protocol; 1607 int err = 0; 1608 1609 for (; tp; tp = tp->next) { 1610 if ((tp->protocol == protocol || 1611 tp->protocol == htons(ETH_P_ALL)) && 1612 (err = tp->classify(skb, tp, res)) >= 0) { 1613 #ifdef CONFIG_NET_CLS_ACT 1614 if (err != TC_ACT_RECLASSIFY && skb->tc_verd) 1615 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0); 1616 #endif 1617 return err; 1618 } 1619 } 1620 return -1; 1621 } 1622 EXPORT_SYMBOL(tc_classify_compat); 1623 1624 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp, 1625 struct tcf_result *res) 1626 { 1627 int err = 0; 1628 __be16 protocol; 1629 #ifdef CONFIG_NET_CLS_ACT 1630 struct tcf_proto *otp = tp; 1631 reclassify: 1632 #endif 1633 protocol = skb->protocol; 1634 1635 err = tc_classify_compat(skb, tp, res); 1636 #ifdef CONFIG_NET_CLS_ACT 1637 if (err == TC_ACT_RECLASSIFY) { 1638 u32 verd = G_TC_VERD(skb->tc_verd); 1639 tp = otp; 1640 1641 if (verd++ >= MAX_REC_LOOP) { 1642 printk("rule prio %u protocol %02x reclassify loop, " 1643 "packet dropped\n", 1644 tp->prio&0xffff, ntohs(tp->protocol)); 1645 return TC_ACT_SHOT; 1646 } 1647 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd); 1648 goto reclassify; 1649 } 1650 #endif 1651 return err; 1652 } 1653 EXPORT_SYMBOL(tc_classify); 1654 1655 void tcf_destroy(struct tcf_proto *tp) 1656 { 1657 tp->ops->destroy(tp); 1658 module_put(tp->ops->owner); 1659 kfree(tp); 1660 } 1661 1662 void tcf_destroy_chain(struct tcf_proto **fl) 1663 { 1664 struct tcf_proto *tp; 1665 1666 while ((tp = *fl) != NULL) { 1667 *fl = tp->next; 1668 tcf_destroy(tp); 1669 } 1670 } 1671 EXPORT_SYMBOL(tcf_destroy_chain); 1672 1673 #ifdef CONFIG_PROC_FS 1674 static int psched_show(struct seq_file *seq, void *v) 1675 { 1676 struct timespec ts; 1677 1678 hrtimer_get_res(CLOCK_MONOTONIC, &ts); 1679 seq_printf(seq, "%08x %08x %08x %08x\n", 1680 (u32)NSEC_PER_USEC, (u32)PSCHED_US2NS(1), 1681 1000000, 1682 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts))); 1683 1684 return 0; 1685 } 1686 1687 static int psched_open(struct inode *inode, struct file *file) 1688 { 1689 return single_open(file, psched_show, PDE(inode)->data); 1690 } 1691 1692 static const struct file_operations psched_fops = { 1693 .owner = THIS_MODULE, 1694 .open = psched_open, 1695 .read = seq_read, 1696 .llseek = seq_lseek, 1697 .release = single_release, 1698 }; 1699 #endif 1700 1701 static int __init pktsched_init(void) 1702 { 1703 register_qdisc(&pfifo_qdisc_ops); 1704 register_qdisc(&bfifo_qdisc_ops); 1705 proc_net_fops_create(&init_net, "psched", 0, &psched_fops); 1706 1707 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL); 1708 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL); 1709 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc); 1710 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL); 1711 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL); 1712 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass); 1713 1714 return 0; 1715 } 1716 1717 subsys_initcall(pktsched_init); 1718