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 ---peek 101 102 like dequeue but without removing a packet from the queue 103 104 ---reset 105 106 returns qdisc to initial state: purge all buffers, clear all 107 timers, counters (except for statistics) etc. 108 109 ---init 110 111 initializes newly created qdisc. 112 113 ---destroy 114 115 destroys resources allocated by init and during lifetime of qdisc. 116 117 ---change 118 119 changes qdisc parameters. 120 */ 121 122 /* Protects list of registered TC modules. It is pure SMP lock. */ 123 static DEFINE_RWLOCK(qdisc_mod_lock); 124 125 126 /************************************************ 127 * Queueing disciplines manipulation. * 128 ************************************************/ 129 130 131 /* The list of all installed queueing disciplines. */ 132 133 static struct Qdisc_ops *qdisc_base; 134 135 /* Register/uregister queueing discipline */ 136 137 int register_qdisc(struct Qdisc_ops *qops) 138 { 139 struct Qdisc_ops *q, **qp; 140 int rc = -EEXIST; 141 142 write_lock(&qdisc_mod_lock); 143 for (qp = &qdisc_base; (q = *qp) != NULL; qp = &q->next) 144 if (!strcmp(qops->id, q->id)) 145 goto out; 146 147 if (qops->enqueue == NULL) 148 qops->enqueue = noop_qdisc_ops.enqueue; 149 if (qops->peek == NULL) { 150 if (qops->dequeue == NULL) { 151 qops->peek = noop_qdisc_ops.peek; 152 } else { 153 rc = -EINVAL; 154 goto out; 155 } 156 } 157 if (qops->dequeue == NULL) 158 qops->dequeue = noop_qdisc_ops.dequeue; 159 160 qops->next = NULL; 161 *qp = qops; 162 rc = 0; 163 out: 164 write_unlock(&qdisc_mod_lock); 165 return rc; 166 } 167 EXPORT_SYMBOL(register_qdisc); 168 169 int unregister_qdisc(struct Qdisc_ops *qops) 170 { 171 struct Qdisc_ops *q, **qp; 172 int err = -ENOENT; 173 174 write_lock(&qdisc_mod_lock); 175 for (qp = &qdisc_base; (q=*qp)!=NULL; qp = &q->next) 176 if (q == qops) 177 break; 178 if (q) { 179 *qp = q->next; 180 q->next = NULL; 181 err = 0; 182 } 183 write_unlock(&qdisc_mod_lock); 184 return err; 185 } 186 EXPORT_SYMBOL(unregister_qdisc); 187 188 /* We know handle. Find qdisc among all qdisc's attached to device 189 (root qdisc, all its children, children of children etc.) 190 */ 191 192 static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) 193 { 194 struct Qdisc *q; 195 196 if (!(root->flags & TCQ_F_BUILTIN) && 197 root->handle == handle) 198 return root; 199 200 list_for_each_entry(q, &root->list, list) { 201 if (q->handle == handle) 202 return q; 203 } 204 return NULL; 205 } 206 207 static void qdisc_list_add(struct Qdisc *q) 208 { 209 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 210 list_add_tail(&q->list, &qdisc_root_sleeping(q)->list); 211 } 212 213 void qdisc_list_del(struct Qdisc *q) 214 { 215 if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) 216 list_del(&q->list); 217 } 218 EXPORT_SYMBOL(qdisc_list_del); 219 220 struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) 221 { 222 unsigned int i; 223 struct Qdisc *q; 224 225 for (i = 0; i < dev->num_tx_queues; i++) { 226 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 227 struct Qdisc *txq_root = txq->qdisc_sleeping; 228 229 q = qdisc_match_from_root(txq_root, handle); 230 if (q) 231 goto out; 232 } 233 234 q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle); 235 out: 236 return q; 237 } 238 239 static struct Qdisc *qdisc_leaf(struct Qdisc *p, u32 classid) 240 { 241 unsigned long cl; 242 struct Qdisc *leaf; 243 const struct Qdisc_class_ops *cops = p->ops->cl_ops; 244 245 if (cops == NULL) 246 return NULL; 247 cl = cops->get(p, classid); 248 249 if (cl == 0) 250 return NULL; 251 leaf = cops->leaf(p, cl); 252 cops->put(p, cl); 253 return leaf; 254 } 255 256 /* Find queueing discipline by name */ 257 258 static struct Qdisc_ops *qdisc_lookup_ops(struct nlattr *kind) 259 { 260 struct Qdisc_ops *q = NULL; 261 262 if (kind) { 263 read_lock(&qdisc_mod_lock); 264 for (q = qdisc_base; q; q = q->next) { 265 if (nla_strcmp(kind, q->id) == 0) { 266 if (!try_module_get(q->owner)) 267 q = NULL; 268 break; 269 } 270 } 271 read_unlock(&qdisc_mod_lock); 272 } 273 return q; 274 } 275 276 static struct qdisc_rate_table *qdisc_rtab_list; 277 278 struct qdisc_rate_table *qdisc_get_rtab(struct tc_ratespec *r, struct nlattr *tab) 279 { 280 struct qdisc_rate_table *rtab; 281 282 for (rtab = qdisc_rtab_list; rtab; rtab = rtab->next) { 283 if (memcmp(&rtab->rate, r, sizeof(struct tc_ratespec)) == 0) { 284 rtab->refcnt++; 285 return rtab; 286 } 287 } 288 289 if (tab == NULL || r->rate == 0 || r->cell_log == 0 || 290 nla_len(tab) != TC_RTAB_SIZE) 291 return NULL; 292 293 rtab = kmalloc(sizeof(*rtab), GFP_KERNEL); 294 if (rtab) { 295 rtab->rate = *r; 296 rtab->refcnt = 1; 297 memcpy(rtab->data, nla_data(tab), 1024); 298 rtab->next = qdisc_rtab_list; 299 qdisc_rtab_list = rtab; 300 } 301 return rtab; 302 } 303 EXPORT_SYMBOL(qdisc_get_rtab); 304 305 void qdisc_put_rtab(struct qdisc_rate_table *tab) 306 { 307 struct qdisc_rate_table *rtab, **rtabp; 308 309 if (!tab || --tab->refcnt) 310 return; 311 312 for (rtabp = &qdisc_rtab_list; (rtab=*rtabp) != NULL; rtabp = &rtab->next) { 313 if (rtab == tab) { 314 *rtabp = rtab->next; 315 kfree(rtab); 316 return; 317 } 318 } 319 } 320 EXPORT_SYMBOL(qdisc_put_rtab); 321 322 static LIST_HEAD(qdisc_stab_list); 323 static DEFINE_SPINLOCK(qdisc_stab_lock); 324 325 static const struct nla_policy stab_policy[TCA_STAB_MAX + 1] = { 326 [TCA_STAB_BASE] = { .len = sizeof(struct tc_sizespec) }, 327 [TCA_STAB_DATA] = { .type = NLA_BINARY }, 328 }; 329 330 static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt) 331 { 332 struct nlattr *tb[TCA_STAB_MAX + 1]; 333 struct qdisc_size_table *stab; 334 struct tc_sizespec *s; 335 unsigned int tsize = 0; 336 u16 *tab = NULL; 337 int err; 338 339 err = nla_parse_nested(tb, TCA_STAB_MAX, opt, stab_policy); 340 if (err < 0) 341 return ERR_PTR(err); 342 if (!tb[TCA_STAB_BASE]) 343 return ERR_PTR(-EINVAL); 344 345 s = nla_data(tb[TCA_STAB_BASE]); 346 347 if (s->tsize > 0) { 348 if (!tb[TCA_STAB_DATA]) 349 return ERR_PTR(-EINVAL); 350 tab = nla_data(tb[TCA_STAB_DATA]); 351 tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16); 352 } 353 354 if (!s || tsize != s->tsize || (!tab && tsize > 0)) 355 return ERR_PTR(-EINVAL); 356 357 spin_lock(&qdisc_stab_lock); 358 359 list_for_each_entry(stab, &qdisc_stab_list, list) { 360 if (memcmp(&stab->szopts, s, sizeof(*s))) 361 continue; 362 if (tsize > 0 && memcmp(stab->data, tab, tsize * sizeof(u16))) 363 continue; 364 stab->refcnt++; 365 spin_unlock(&qdisc_stab_lock); 366 return stab; 367 } 368 369 spin_unlock(&qdisc_stab_lock); 370 371 stab = kmalloc(sizeof(*stab) + tsize * sizeof(u16), GFP_KERNEL); 372 if (!stab) 373 return ERR_PTR(-ENOMEM); 374 375 stab->refcnt = 1; 376 stab->szopts = *s; 377 if (tsize > 0) 378 memcpy(stab->data, tab, tsize * sizeof(u16)); 379 380 spin_lock(&qdisc_stab_lock); 381 list_add_tail(&stab->list, &qdisc_stab_list); 382 spin_unlock(&qdisc_stab_lock); 383 384 return stab; 385 } 386 387 void qdisc_put_stab(struct qdisc_size_table *tab) 388 { 389 if (!tab) 390 return; 391 392 spin_lock(&qdisc_stab_lock); 393 394 if (--tab->refcnt == 0) { 395 list_del(&tab->list); 396 kfree(tab); 397 } 398 399 spin_unlock(&qdisc_stab_lock); 400 } 401 EXPORT_SYMBOL(qdisc_put_stab); 402 403 static int qdisc_dump_stab(struct sk_buff *skb, struct qdisc_size_table *stab) 404 { 405 struct nlattr *nest; 406 407 nest = nla_nest_start(skb, TCA_STAB); 408 if (nest == NULL) 409 goto nla_put_failure; 410 NLA_PUT(skb, TCA_STAB_BASE, sizeof(stab->szopts), &stab->szopts); 411 nla_nest_end(skb, nest); 412 413 return skb->len; 414 415 nla_put_failure: 416 return -1; 417 } 418 419 void qdisc_calculate_pkt_len(struct sk_buff *skb, struct qdisc_size_table *stab) 420 { 421 int pkt_len, slot; 422 423 pkt_len = skb->len + stab->szopts.overhead; 424 if (unlikely(!stab->szopts.tsize)) 425 goto out; 426 427 slot = pkt_len + stab->szopts.cell_align; 428 if (unlikely(slot < 0)) 429 slot = 0; 430 431 slot >>= stab->szopts.cell_log; 432 if (likely(slot < stab->szopts.tsize)) 433 pkt_len = stab->data[slot]; 434 else 435 pkt_len = stab->data[stab->szopts.tsize - 1] * 436 (slot / stab->szopts.tsize) + 437 stab->data[slot % stab->szopts.tsize]; 438 439 pkt_len <<= stab->szopts.size_log; 440 out: 441 if (unlikely(pkt_len < 1)) 442 pkt_len = 1; 443 qdisc_skb_cb(skb)->pkt_len = pkt_len; 444 } 445 EXPORT_SYMBOL(qdisc_calculate_pkt_len); 446 447 void qdisc_warn_nonwc(char *txt, struct Qdisc *qdisc) 448 { 449 if (!(qdisc->flags & TCQ_F_WARN_NONWC)) { 450 printk(KERN_WARNING 451 "%s: %s qdisc %X: is non-work-conserving?\n", 452 txt, qdisc->ops->id, qdisc->handle >> 16); 453 qdisc->flags |= TCQ_F_WARN_NONWC; 454 } 455 } 456 EXPORT_SYMBOL(qdisc_warn_nonwc); 457 458 static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer) 459 { 460 struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog, 461 timer); 462 463 wd->qdisc->flags &= ~TCQ_F_THROTTLED; 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 /* NB: ignores errors from replace_estimator 894 because change can't be undone. */ 895 gen_replace_estimator(&sch->bstats, &sch->rate_est, 896 qdisc_root_sleeping_lock(sch), 897 tca[TCA_RATE]); 898 899 return 0; 900 } 901 902 struct check_loop_arg 903 { 904 struct qdisc_walker w; 905 struct Qdisc *p; 906 int depth; 907 }; 908 909 static int check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w); 910 911 static int check_loop(struct Qdisc *q, struct Qdisc *p, int depth) 912 { 913 struct check_loop_arg arg; 914 915 if (q->ops->cl_ops == NULL) 916 return 0; 917 918 arg.w.stop = arg.w.skip = arg.w.count = 0; 919 arg.w.fn = check_loop_fn; 920 arg.depth = depth; 921 arg.p = p; 922 q->ops->cl_ops->walk(q, &arg.w); 923 return arg.w.stop ? -ELOOP : 0; 924 } 925 926 static int 927 check_loop_fn(struct Qdisc *q, unsigned long cl, struct qdisc_walker *w) 928 { 929 struct Qdisc *leaf; 930 const struct Qdisc_class_ops *cops = q->ops->cl_ops; 931 struct check_loop_arg *arg = (struct check_loop_arg *)w; 932 933 leaf = cops->leaf(q, cl); 934 if (leaf) { 935 if (leaf == arg->p || arg->depth > 7) 936 return -ELOOP; 937 return check_loop(leaf, arg->p, arg->depth + 1); 938 } 939 return 0; 940 } 941 942 /* 943 * Delete/get qdisc. 944 */ 945 946 static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 947 { 948 struct net *net = sock_net(skb->sk); 949 struct tcmsg *tcm = NLMSG_DATA(n); 950 struct nlattr *tca[TCA_MAX + 1]; 951 struct net_device *dev; 952 u32 clid = tcm->tcm_parent; 953 struct Qdisc *q = NULL; 954 struct Qdisc *p = NULL; 955 int err; 956 957 if (net != &init_net) 958 return -EINVAL; 959 960 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 961 return -ENODEV; 962 963 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 964 if (err < 0) 965 return err; 966 967 if (clid) { 968 if (clid != TC_H_ROOT) { 969 if (TC_H_MAJ(clid) != TC_H_MAJ(TC_H_INGRESS)) { 970 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 971 return -ENOENT; 972 q = qdisc_leaf(p, clid); 973 } else { /* ingress */ 974 q = dev->rx_queue.qdisc_sleeping; 975 } 976 } else { 977 struct netdev_queue *dev_queue; 978 dev_queue = netdev_get_tx_queue(dev, 0); 979 q = dev_queue->qdisc_sleeping; 980 } 981 if (!q) 982 return -ENOENT; 983 984 if (tcm->tcm_handle && q->handle != tcm->tcm_handle) 985 return -EINVAL; 986 } else { 987 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 988 return -ENOENT; 989 } 990 991 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 992 return -EINVAL; 993 994 if (n->nlmsg_type == RTM_DELQDISC) { 995 if (!clid) 996 return -EINVAL; 997 if (q->handle == 0) 998 return -ENOENT; 999 if ((err = qdisc_graft(dev, p, skb, n, clid, NULL, q)) != 0) 1000 return err; 1001 } else { 1002 qdisc_notify(skb, n, clid, NULL, q); 1003 } 1004 return 0; 1005 } 1006 1007 /* 1008 Create/change qdisc. 1009 */ 1010 1011 static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1012 { 1013 struct net *net = sock_net(skb->sk); 1014 struct tcmsg *tcm; 1015 struct nlattr *tca[TCA_MAX + 1]; 1016 struct net_device *dev; 1017 u32 clid; 1018 struct Qdisc *q, *p; 1019 int err; 1020 1021 if (net != &init_net) 1022 return -EINVAL; 1023 1024 replay: 1025 /* Reinit, just in case something touches this. */ 1026 tcm = NLMSG_DATA(n); 1027 clid = tcm->tcm_parent; 1028 q = p = NULL; 1029 1030 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1031 return -ENODEV; 1032 1033 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1034 if (err < 0) 1035 return err; 1036 1037 if (clid) { 1038 if (clid != TC_H_ROOT) { 1039 if (clid != TC_H_INGRESS) { 1040 if ((p = qdisc_lookup(dev, TC_H_MAJ(clid))) == NULL) 1041 return -ENOENT; 1042 q = qdisc_leaf(p, clid); 1043 } else { /*ingress */ 1044 q = dev->rx_queue.qdisc_sleeping; 1045 } 1046 } else { 1047 struct netdev_queue *dev_queue; 1048 dev_queue = netdev_get_tx_queue(dev, 0); 1049 q = dev_queue->qdisc_sleeping; 1050 } 1051 1052 /* It may be default qdisc, ignore it */ 1053 if (q && q->handle == 0) 1054 q = NULL; 1055 1056 if (!q || !tcm->tcm_handle || q->handle != tcm->tcm_handle) { 1057 if (tcm->tcm_handle) { 1058 if (q && !(n->nlmsg_flags&NLM_F_REPLACE)) 1059 return -EEXIST; 1060 if (TC_H_MIN(tcm->tcm_handle)) 1061 return -EINVAL; 1062 if ((q = qdisc_lookup(dev, tcm->tcm_handle)) == NULL) 1063 goto create_n_graft; 1064 if (n->nlmsg_flags&NLM_F_EXCL) 1065 return -EEXIST; 1066 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1067 return -EINVAL; 1068 if (q == p || 1069 (p && check_loop(q, p, 0))) 1070 return -ELOOP; 1071 atomic_inc(&q->refcnt); 1072 goto graft; 1073 } else { 1074 if (q == NULL) 1075 goto create_n_graft; 1076 1077 /* This magic test requires explanation. 1078 * 1079 * We know, that some child q is already 1080 * attached to this parent and have choice: 1081 * either to change it or to create/graft new one. 1082 * 1083 * 1. We are allowed to create/graft only 1084 * if CREATE and REPLACE flags are set. 1085 * 1086 * 2. If EXCL is set, requestor wanted to say, 1087 * that qdisc tcm_handle is not expected 1088 * to exist, so that we choose create/graft too. 1089 * 1090 * 3. The last case is when no flags are set. 1091 * Alas, it is sort of hole in API, we 1092 * cannot decide what to do unambiguously. 1093 * For now we select create/graft, if 1094 * user gave KIND, which does not match existing. 1095 */ 1096 if ((n->nlmsg_flags&NLM_F_CREATE) && 1097 (n->nlmsg_flags&NLM_F_REPLACE) && 1098 ((n->nlmsg_flags&NLM_F_EXCL) || 1099 (tca[TCA_KIND] && 1100 nla_strcmp(tca[TCA_KIND], q->ops->id)))) 1101 goto create_n_graft; 1102 } 1103 } 1104 } else { 1105 if (!tcm->tcm_handle) 1106 return -EINVAL; 1107 q = qdisc_lookup(dev, tcm->tcm_handle); 1108 } 1109 1110 /* Change qdisc parameters */ 1111 if (q == NULL) 1112 return -ENOENT; 1113 if (n->nlmsg_flags&NLM_F_EXCL) 1114 return -EEXIST; 1115 if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], q->ops->id)) 1116 return -EINVAL; 1117 err = qdisc_change(q, tca); 1118 if (err == 0) 1119 qdisc_notify(skb, n, clid, NULL, q); 1120 return err; 1121 1122 create_n_graft: 1123 if (!(n->nlmsg_flags&NLM_F_CREATE)) 1124 return -ENOENT; 1125 if (clid == TC_H_INGRESS) 1126 q = qdisc_create(dev, &dev->rx_queue, 1127 tcm->tcm_parent, tcm->tcm_parent, 1128 tca, &err); 1129 else 1130 q = qdisc_create(dev, netdev_get_tx_queue(dev, 0), 1131 tcm->tcm_parent, tcm->tcm_handle, 1132 tca, &err); 1133 if (q == NULL) { 1134 if (err == -EAGAIN) 1135 goto replay; 1136 return err; 1137 } 1138 1139 graft: 1140 err = qdisc_graft(dev, p, skb, n, clid, q, NULL); 1141 if (err) { 1142 if (q) 1143 qdisc_destroy(q); 1144 return err; 1145 } 1146 1147 return 0; 1148 } 1149 1150 static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid, 1151 u32 pid, u32 seq, u16 flags, int event) 1152 { 1153 struct tcmsg *tcm; 1154 struct nlmsghdr *nlh; 1155 unsigned char *b = skb_tail_pointer(skb); 1156 struct gnet_dump d; 1157 1158 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1159 tcm = NLMSG_DATA(nlh); 1160 tcm->tcm_family = AF_UNSPEC; 1161 tcm->tcm__pad1 = 0; 1162 tcm->tcm__pad2 = 0; 1163 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1164 tcm->tcm_parent = clid; 1165 tcm->tcm_handle = q->handle; 1166 tcm->tcm_info = atomic_read(&q->refcnt); 1167 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1168 if (q->ops->dump && q->ops->dump(q, skb) < 0) 1169 goto nla_put_failure; 1170 q->qstats.qlen = q->q.qlen; 1171 1172 if (q->stab && qdisc_dump_stab(skb, q->stab) < 0) 1173 goto nla_put_failure; 1174 1175 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1176 qdisc_root_sleeping_lock(q), &d) < 0) 1177 goto nla_put_failure; 1178 1179 if (q->ops->dump_stats && q->ops->dump_stats(q, &d) < 0) 1180 goto nla_put_failure; 1181 1182 if (gnet_stats_copy_basic(&d, &q->bstats) < 0 || 1183 gnet_stats_copy_rate_est(&d, &q->rate_est) < 0 || 1184 gnet_stats_copy_queue(&d, &q->qstats) < 0) 1185 goto nla_put_failure; 1186 1187 if (gnet_stats_finish_copy(&d) < 0) 1188 goto nla_put_failure; 1189 1190 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1191 return skb->len; 1192 1193 nlmsg_failure: 1194 nla_put_failure: 1195 nlmsg_trim(skb, b); 1196 return -1; 1197 } 1198 1199 static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1200 u32 clid, struct Qdisc *old, struct Qdisc *new) 1201 { 1202 struct sk_buff *skb; 1203 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1204 1205 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1206 if (!skb) 1207 return -ENOBUFS; 1208 1209 if (old && old->handle) { 1210 if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0) 1211 goto err_out; 1212 } 1213 if (new) { 1214 if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0) 1215 goto err_out; 1216 } 1217 1218 if (skb->len) 1219 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1220 1221 err_out: 1222 kfree_skb(skb); 1223 return -EINVAL; 1224 } 1225 1226 static bool tc_qdisc_dump_ignore(struct Qdisc *q) 1227 { 1228 return (q->flags & TCQ_F_BUILTIN) ? true : false; 1229 } 1230 1231 static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb, 1232 struct netlink_callback *cb, 1233 int *q_idx_p, int s_q_idx) 1234 { 1235 int ret = 0, q_idx = *q_idx_p; 1236 struct Qdisc *q; 1237 1238 if (!root) 1239 return 0; 1240 1241 q = root; 1242 if (q_idx < s_q_idx) { 1243 q_idx++; 1244 } else { 1245 if (!tc_qdisc_dump_ignore(q) && 1246 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1247 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1248 goto done; 1249 q_idx++; 1250 } 1251 list_for_each_entry(q, &root->list, list) { 1252 if (q_idx < s_q_idx) { 1253 q_idx++; 1254 continue; 1255 } 1256 if (!tc_qdisc_dump_ignore(q) && 1257 tc_fill_qdisc(skb, q, q->parent, NETLINK_CB(cb->skb).pid, 1258 cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWQDISC) <= 0) 1259 goto done; 1260 q_idx++; 1261 } 1262 1263 out: 1264 *q_idx_p = q_idx; 1265 return ret; 1266 done: 1267 ret = -1; 1268 goto out; 1269 } 1270 1271 static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 1272 { 1273 struct net *net = sock_net(skb->sk); 1274 int idx, q_idx; 1275 int s_idx, s_q_idx; 1276 struct net_device *dev; 1277 1278 if (net != &init_net) 1279 return 0; 1280 1281 s_idx = cb->args[0]; 1282 s_q_idx = q_idx = cb->args[1]; 1283 read_lock(&dev_base_lock); 1284 idx = 0; 1285 for_each_netdev(&init_net, dev) { 1286 struct netdev_queue *dev_queue; 1287 1288 if (idx < s_idx) 1289 goto cont; 1290 if (idx > s_idx) 1291 s_q_idx = 0; 1292 q_idx = 0; 1293 1294 dev_queue = netdev_get_tx_queue(dev, 0); 1295 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1296 goto done; 1297 1298 dev_queue = &dev->rx_queue; 1299 if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) 1300 goto done; 1301 1302 cont: 1303 idx++; 1304 } 1305 1306 done: 1307 read_unlock(&dev_base_lock); 1308 1309 cb->args[0] = idx; 1310 cb->args[1] = q_idx; 1311 1312 return skb->len; 1313 } 1314 1315 1316 1317 /************************************************ 1318 * Traffic classes manipulation. * 1319 ************************************************/ 1320 1321 1322 1323 static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) 1324 { 1325 struct net *net = sock_net(skb->sk); 1326 struct netdev_queue *dev_queue; 1327 struct tcmsg *tcm = NLMSG_DATA(n); 1328 struct nlattr *tca[TCA_MAX + 1]; 1329 struct net_device *dev; 1330 struct Qdisc *q = NULL; 1331 const struct Qdisc_class_ops *cops; 1332 unsigned long cl = 0; 1333 unsigned long new_cl; 1334 u32 pid = tcm->tcm_parent; 1335 u32 clid = tcm->tcm_handle; 1336 u32 qid = TC_H_MAJ(clid); 1337 int err; 1338 1339 if (net != &init_net) 1340 return -EINVAL; 1341 1342 if ((dev = __dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1343 return -ENODEV; 1344 1345 err = nlmsg_parse(n, sizeof(*tcm), tca, TCA_MAX, NULL); 1346 if (err < 0) 1347 return err; 1348 1349 /* 1350 parent == TC_H_UNSPEC - unspecified parent. 1351 parent == TC_H_ROOT - class is root, which has no parent. 1352 parent == X:0 - parent is root class. 1353 parent == X:Y - parent is a node in hierarchy. 1354 parent == 0:Y - parent is X:Y, where X:0 is qdisc. 1355 1356 handle == 0:0 - generate handle from kernel pool. 1357 handle == 0:Y - class is X:Y, where X:0 is qdisc. 1358 handle == X:Y - clear. 1359 handle == X:0 - root class. 1360 */ 1361 1362 /* Step 1. Determine qdisc handle X:0 */ 1363 1364 dev_queue = netdev_get_tx_queue(dev, 0); 1365 if (pid != TC_H_ROOT) { 1366 u32 qid1 = TC_H_MAJ(pid); 1367 1368 if (qid && qid1) { 1369 /* If both majors are known, they must be identical. */ 1370 if (qid != qid1) 1371 return -EINVAL; 1372 } else if (qid1) { 1373 qid = qid1; 1374 } else if (qid == 0) 1375 qid = dev_queue->qdisc_sleeping->handle; 1376 1377 /* Now qid is genuine qdisc handle consistent 1378 both with parent and child. 1379 1380 TC_H_MAJ(pid) still may be unspecified, complete it now. 1381 */ 1382 if (pid) 1383 pid = TC_H_MAKE(qid, pid); 1384 } else { 1385 if (qid == 0) 1386 qid = dev_queue->qdisc_sleeping->handle; 1387 } 1388 1389 /* OK. Locate qdisc */ 1390 if ((q = qdisc_lookup(dev, qid)) == NULL) 1391 return -ENOENT; 1392 1393 /* An check that it supports classes */ 1394 cops = q->ops->cl_ops; 1395 if (cops == NULL) 1396 return -EINVAL; 1397 1398 /* Now try to get class */ 1399 if (clid == 0) { 1400 if (pid == TC_H_ROOT) 1401 clid = qid; 1402 } else 1403 clid = TC_H_MAKE(qid, clid); 1404 1405 if (clid) 1406 cl = cops->get(q, clid); 1407 1408 if (cl == 0) { 1409 err = -ENOENT; 1410 if (n->nlmsg_type != RTM_NEWTCLASS || !(n->nlmsg_flags&NLM_F_CREATE)) 1411 goto out; 1412 } else { 1413 switch (n->nlmsg_type) { 1414 case RTM_NEWTCLASS: 1415 err = -EEXIST; 1416 if (n->nlmsg_flags&NLM_F_EXCL) 1417 goto out; 1418 break; 1419 case RTM_DELTCLASS: 1420 err = cops->delete(q, cl); 1421 if (err == 0) 1422 tclass_notify(skb, n, q, cl, RTM_DELTCLASS); 1423 goto out; 1424 case RTM_GETTCLASS: 1425 err = tclass_notify(skb, n, q, cl, RTM_NEWTCLASS); 1426 goto out; 1427 default: 1428 err = -EINVAL; 1429 goto out; 1430 } 1431 } 1432 1433 new_cl = cl; 1434 err = cops->change(q, clid, pid, tca, &new_cl); 1435 if (err == 0) 1436 tclass_notify(skb, n, q, new_cl, RTM_NEWTCLASS); 1437 1438 out: 1439 if (cl) 1440 cops->put(q, cl); 1441 1442 return err; 1443 } 1444 1445 1446 static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q, 1447 unsigned long cl, 1448 u32 pid, u32 seq, u16 flags, int event) 1449 { 1450 struct tcmsg *tcm; 1451 struct nlmsghdr *nlh; 1452 unsigned char *b = skb_tail_pointer(skb); 1453 struct gnet_dump d; 1454 const struct Qdisc_class_ops *cl_ops = q->ops->cl_ops; 1455 1456 nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags); 1457 tcm = NLMSG_DATA(nlh); 1458 tcm->tcm_family = AF_UNSPEC; 1459 tcm->tcm_ifindex = qdisc_dev(q)->ifindex; 1460 tcm->tcm_parent = q->handle; 1461 tcm->tcm_handle = q->handle; 1462 tcm->tcm_info = 0; 1463 NLA_PUT_STRING(skb, TCA_KIND, q->ops->id); 1464 if (cl_ops->dump && cl_ops->dump(q, cl, skb, tcm) < 0) 1465 goto nla_put_failure; 1466 1467 if (gnet_stats_start_copy_compat(skb, TCA_STATS2, TCA_STATS, TCA_XSTATS, 1468 qdisc_root_sleeping_lock(q), &d) < 0) 1469 goto nla_put_failure; 1470 1471 if (cl_ops->dump_stats && cl_ops->dump_stats(q, cl, &d) < 0) 1472 goto nla_put_failure; 1473 1474 if (gnet_stats_finish_copy(&d) < 0) 1475 goto nla_put_failure; 1476 1477 nlh->nlmsg_len = skb_tail_pointer(skb) - b; 1478 return skb->len; 1479 1480 nlmsg_failure: 1481 nla_put_failure: 1482 nlmsg_trim(skb, b); 1483 return -1; 1484 } 1485 1486 static int tclass_notify(struct sk_buff *oskb, struct nlmsghdr *n, 1487 struct Qdisc *q, unsigned long cl, int event) 1488 { 1489 struct sk_buff *skb; 1490 u32 pid = oskb ? NETLINK_CB(oskb).pid : 0; 1491 1492 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); 1493 if (!skb) 1494 return -ENOBUFS; 1495 1496 if (tc_fill_tclass(skb, q, cl, pid, n->nlmsg_seq, 0, event) < 0) { 1497 kfree_skb(skb); 1498 return -EINVAL; 1499 } 1500 1501 return rtnetlink_send(skb, &init_net, pid, RTNLGRP_TC, n->nlmsg_flags&NLM_F_ECHO); 1502 } 1503 1504 struct qdisc_dump_args 1505 { 1506 struct qdisc_walker w; 1507 struct sk_buff *skb; 1508 struct netlink_callback *cb; 1509 }; 1510 1511 static int qdisc_class_dump(struct Qdisc *q, unsigned long cl, struct qdisc_walker *arg) 1512 { 1513 struct qdisc_dump_args *a = (struct qdisc_dump_args *)arg; 1514 1515 return tc_fill_tclass(a->skb, q, cl, NETLINK_CB(a->cb->skb).pid, 1516 a->cb->nlh->nlmsg_seq, NLM_F_MULTI, RTM_NEWTCLASS); 1517 } 1518 1519 static int tc_dump_tclass_qdisc(struct Qdisc *q, struct sk_buff *skb, 1520 struct tcmsg *tcm, struct netlink_callback *cb, 1521 int *t_p, int s_t) 1522 { 1523 struct qdisc_dump_args arg; 1524 1525 if (tc_qdisc_dump_ignore(q) || 1526 *t_p < s_t || !q->ops->cl_ops || 1527 (tcm->tcm_parent && 1528 TC_H_MAJ(tcm->tcm_parent) != q->handle)) { 1529 (*t_p)++; 1530 return 0; 1531 } 1532 if (*t_p > s_t) 1533 memset(&cb->args[1], 0, sizeof(cb->args)-sizeof(cb->args[0])); 1534 arg.w.fn = qdisc_class_dump; 1535 arg.skb = skb; 1536 arg.cb = cb; 1537 arg.w.stop = 0; 1538 arg.w.skip = cb->args[1]; 1539 arg.w.count = 0; 1540 q->ops->cl_ops->walk(q, &arg.w); 1541 cb->args[1] = arg.w.count; 1542 if (arg.w.stop) 1543 return -1; 1544 (*t_p)++; 1545 return 0; 1546 } 1547 1548 static int tc_dump_tclass_root(struct Qdisc *root, struct sk_buff *skb, 1549 struct tcmsg *tcm, struct netlink_callback *cb, 1550 int *t_p, int s_t) 1551 { 1552 struct Qdisc *q; 1553 1554 if (!root) 1555 return 0; 1556 1557 if (tc_dump_tclass_qdisc(root, skb, tcm, cb, t_p, s_t) < 0) 1558 return -1; 1559 1560 list_for_each_entry(q, &root->list, list) { 1561 if (tc_dump_tclass_qdisc(q, skb, tcm, cb, t_p, s_t) < 0) 1562 return -1; 1563 } 1564 1565 return 0; 1566 } 1567 1568 static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 1569 { 1570 struct tcmsg *tcm = (struct tcmsg*)NLMSG_DATA(cb->nlh); 1571 struct net *net = sock_net(skb->sk); 1572 struct netdev_queue *dev_queue; 1573 struct net_device *dev; 1574 int t, s_t; 1575 1576 if (net != &init_net) 1577 return 0; 1578 1579 if (cb->nlh->nlmsg_len < NLMSG_LENGTH(sizeof(*tcm))) 1580 return 0; 1581 if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) 1582 return 0; 1583 1584 s_t = cb->args[0]; 1585 t = 0; 1586 1587 dev_queue = netdev_get_tx_queue(dev, 0); 1588 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1589 goto done; 1590 1591 dev_queue = &dev->rx_queue; 1592 if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) 1593 goto done; 1594 1595 done: 1596 cb->args[0] = t; 1597 1598 dev_put(dev); 1599 return skb->len; 1600 } 1601 1602 /* Main classifier routine: scans classifier chain attached 1603 to this qdisc, (optionally) tests for protocol and asks 1604 specific classifiers. 1605 */ 1606 int tc_classify_compat(struct sk_buff *skb, struct tcf_proto *tp, 1607 struct tcf_result *res) 1608 { 1609 __be16 protocol = skb->protocol; 1610 int err = 0; 1611 1612 for (; tp; tp = tp->next) { 1613 if ((tp->protocol == protocol || 1614 tp->protocol == htons(ETH_P_ALL)) && 1615 (err = tp->classify(skb, tp, res)) >= 0) { 1616 #ifdef CONFIG_NET_CLS_ACT 1617 if (err != TC_ACT_RECLASSIFY && skb->tc_verd) 1618 skb->tc_verd = SET_TC_VERD(skb->tc_verd, 0); 1619 #endif 1620 return err; 1621 } 1622 } 1623 return -1; 1624 } 1625 EXPORT_SYMBOL(tc_classify_compat); 1626 1627 int tc_classify(struct sk_buff *skb, struct tcf_proto *tp, 1628 struct tcf_result *res) 1629 { 1630 int err = 0; 1631 __be16 protocol; 1632 #ifdef CONFIG_NET_CLS_ACT 1633 struct tcf_proto *otp = tp; 1634 reclassify: 1635 #endif 1636 protocol = skb->protocol; 1637 1638 err = tc_classify_compat(skb, tp, res); 1639 #ifdef CONFIG_NET_CLS_ACT 1640 if (err == TC_ACT_RECLASSIFY) { 1641 u32 verd = G_TC_VERD(skb->tc_verd); 1642 tp = otp; 1643 1644 if (verd++ >= MAX_REC_LOOP) { 1645 printk("rule prio %u protocol %02x reclassify loop, " 1646 "packet dropped\n", 1647 tp->prio&0xffff, ntohs(tp->protocol)); 1648 return TC_ACT_SHOT; 1649 } 1650 skb->tc_verd = SET_TC_VERD(skb->tc_verd, verd); 1651 goto reclassify; 1652 } 1653 #endif 1654 return err; 1655 } 1656 EXPORT_SYMBOL(tc_classify); 1657 1658 void tcf_destroy(struct tcf_proto *tp) 1659 { 1660 tp->ops->destroy(tp); 1661 module_put(tp->ops->owner); 1662 kfree(tp); 1663 } 1664 1665 void tcf_destroy_chain(struct tcf_proto **fl) 1666 { 1667 struct tcf_proto *tp; 1668 1669 while ((tp = *fl) != NULL) { 1670 *fl = tp->next; 1671 tcf_destroy(tp); 1672 } 1673 } 1674 EXPORT_SYMBOL(tcf_destroy_chain); 1675 1676 #ifdef CONFIG_PROC_FS 1677 static int psched_show(struct seq_file *seq, void *v) 1678 { 1679 struct timespec ts; 1680 1681 hrtimer_get_res(CLOCK_MONOTONIC, &ts); 1682 seq_printf(seq, "%08x %08x %08x %08x\n", 1683 (u32)NSEC_PER_USEC, (u32)PSCHED_US2NS(1), 1684 1000000, 1685 (u32)NSEC_PER_SEC/(u32)ktime_to_ns(timespec_to_ktime(ts))); 1686 1687 return 0; 1688 } 1689 1690 static int psched_open(struct inode *inode, struct file *file) 1691 { 1692 return single_open(file, psched_show, PDE(inode)->data); 1693 } 1694 1695 static const struct file_operations psched_fops = { 1696 .owner = THIS_MODULE, 1697 .open = psched_open, 1698 .read = seq_read, 1699 .llseek = seq_lseek, 1700 .release = single_release, 1701 }; 1702 #endif 1703 1704 static int __init pktsched_init(void) 1705 { 1706 register_qdisc(&pfifo_qdisc_ops); 1707 register_qdisc(&bfifo_qdisc_ops); 1708 proc_net_fops_create(&init_net, "psched", 0, &psched_fops); 1709 1710 rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL); 1711 rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL); 1712 rtnl_register(PF_UNSPEC, RTM_GETQDISC, tc_get_qdisc, tc_dump_qdisc); 1713 rtnl_register(PF_UNSPEC, RTM_NEWTCLASS, tc_ctl_tclass, NULL); 1714 rtnl_register(PF_UNSPEC, RTM_DELTCLASS, tc_ctl_tclass, NULL); 1715 rtnl_register(PF_UNSPEC, RTM_GETTCLASS, tc_ctl_tclass, tc_dump_tclass); 1716 1717 return 0; 1718 } 1719 1720 subsys_initcall(pktsched_init); 1721