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