1 #ifndef __NET_SCHED_GENERIC_H 2 #define __NET_SCHED_GENERIC_H 3 4 #include <linux/netdevice.h> 5 #include <linux/types.h> 6 #include <linux/rcupdate.h> 7 #include <linux/pkt_sched.h> 8 #include <linux/pkt_cls.h> 9 #include <linux/percpu.h> 10 #include <linux/dynamic_queue_limits.h> 11 #include <net/gen_stats.h> 12 #include <net/rtnetlink.h> 13 14 struct Qdisc_ops; 15 struct qdisc_walker; 16 struct tcf_walker; 17 struct module; 18 19 struct qdisc_rate_table { 20 struct tc_ratespec rate; 21 u32 data[256]; 22 struct qdisc_rate_table *next; 23 int refcnt; 24 }; 25 26 enum qdisc_state_t { 27 __QDISC_STATE_SCHED, 28 __QDISC_STATE_DEACTIVATED, 29 __QDISC_STATE_THROTTLED, 30 }; 31 32 /* 33 * following bits are only changed while qdisc lock is held 34 */ 35 enum qdisc___state_t { 36 __QDISC___STATE_RUNNING = 1, 37 }; 38 39 struct qdisc_size_table { 40 struct rcu_head rcu; 41 struct list_head list; 42 struct tc_sizespec szopts; 43 int refcnt; 44 u16 data[]; 45 }; 46 47 struct Qdisc { 48 int (*enqueue)(struct sk_buff *skb, struct Qdisc *dev); 49 struct sk_buff * (*dequeue)(struct Qdisc *dev); 50 unsigned int flags; 51 #define TCQ_F_BUILTIN 1 52 #define TCQ_F_INGRESS 2 53 #define TCQ_F_CAN_BYPASS 4 54 #define TCQ_F_MQROOT 8 55 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for 56 * q->dev_queue : It can test 57 * netif_xmit_frozen_or_stopped() before 58 * dequeueing next packet. 59 * Its true for MQ/MQPRIO slaves, or non 60 * multiqueue device. 61 */ 62 #define TCQ_F_WARN_NONWC (1 << 16) 63 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */ 64 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy : 65 * qdisc_tree_decrease_qlen() should stop. 66 */ 67 u32 limit; 68 const struct Qdisc_ops *ops; 69 struct qdisc_size_table __rcu *stab; 70 struct list_head list; 71 u32 handle; 72 u32 parent; 73 int (*reshape_fail)(struct sk_buff *skb, 74 struct Qdisc *q); 75 76 void *u32_node; 77 78 /* This field is deprecated, but it is still used by CBQ 79 * and it will live until better solution will be invented. 80 */ 81 struct Qdisc *__parent; 82 struct netdev_queue *dev_queue; 83 84 struct gnet_stats_rate_est64 rate_est; 85 struct gnet_stats_basic_cpu __percpu *cpu_bstats; 86 struct gnet_stats_queue __percpu *cpu_qstats; 87 88 struct Qdisc *next_sched; 89 struct sk_buff *gso_skb; 90 /* 91 * For performance sake on SMP, we put highly modified fields at the end 92 */ 93 unsigned long state; 94 struct sk_buff_head q; 95 struct gnet_stats_basic_packed bstats; 96 unsigned int __state; 97 struct gnet_stats_queue qstats; 98 struct rcu_head rcu_head; 99 int padded; 100 atomic_t refcnt; 101 102 spinlock_t busylock ____cacheline_aligned_in_smp; 103 }; 104 105 static inline bool qdisc_is_running(const struct Qdisc *qdisc) 106 { 107 return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false; 108 } 109 110 static inline bool qdisc_run_begin(struct Qdisc *qdisc) 111 { 112 if (qdisc_is_running(qdisc)) 113 return false; 114 qdisc->__state |= __QDISC___STATE_RUNNING; 115 return true; 116 } 117 118 static inline void qdisc_run_end(struct Qdisc *qdisc) 119 { 120 qdisc->__state &= ~__QDISC___STATE_RUNNING; 121 } 122 123 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc) 124 { 125 return qdisc->flags & TCQ_F_ONETXQUEUE; 126 } 127 128 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq) 129 { 130 #ifdef CONFIG_BQL 131 /* Non-BQL migrated drivers will return 0, too. */ 132 return dql_avail(&txq->dql); 133 #else 134 return 0; 135 #endif 136 } 137 138 static inline bool qdisc_is_throttled(const struct Qdisc *qdisc) 139 { 140 return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false; 141 } 142 143 static inline void qdisc_throttled(struct Qdisc *qdisc) 144 { 145 set_bit(__QDISC_STATE_THROTTLED, &qdisc->state); 146 } 147 148 static inline void qdisc_unthrottled(struct Qdisc *qdisc) 149 { 150 clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state); 151 } 152 153 struct Qdisc_class_ops { 154 /* Child qdisc manipulation */ 155 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *); 156 int (*graft)(struct Qdisc *, unsigned long cl, 157 struct Qdisc *, struct Qdisc **); 158 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl); 159 void (*qlen_notify)(struct Qdisc *, unsigned long); 160 161 /* Class manipulation routines */ 162 unsigned long (*get)(struct Qdisc *, u32 classid); 163 void (*put)(struct Qdisc *, unsigned long); 164 int (*change)(struct Qdisc *, u32, u32, 165 struct nlattr **, unsigned long *); 166 int (*delete)(struct Qdisc *, unsigned long); 167 void (*walk)(struct Qdisc *, struct qdisc_walker * arg); 168 169 /* Filter manipulation */ 170 struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long); 171 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long, 172 u32 classid); 173 void (*unbind_tcf)(struct Qdisc *, unsigned long); 174 175 /* rtnetlink specific */ 176 int (*dump)(struct Qdisc *, unsigned long, 177 struct sk_buff *skb, struct tcmsg*); 178 int (*dump_stats)(struct Qdisc *, unsigned long, 179 struct gnet_dump *); 180 }; 181 182 struct Qdisc_ops { 183 struct Qdisc_ops *next; 184 const struct Qdisc_class_ops *cl_ops; 185 char id[IFNAMSIZ]; 186 int priv_size; 187 188 int (*enqueue)(struct sk_buff *, struct Qdisc *); 189 struct sk_buff * (*dequeue)(struct Qdisc *); 190 struct sk_buff * (*peek)(struct Qdisc *); 191 unsigned int (*drop)(struct Qdisc *); 192 193 int (*init)(struct Qdisc *, struct nlattr *arg); 194 void (*reset)(struct Qdisc *); 195 void (*destroy)(struct Qdisc *); 196 int (*change)(struct Qdisc *, struct nlattr *arg); 197 void (*attach)(struct Qdisc *); 198 199 int (*dump)(struct Qdisc *, struct sk_buff *); 200 int (*dump_stats)(struct Qdisc *, struct gnet_dump *); 201 202 struct module *owner; 203 }; 204 205 206 struct tcf_result { 207 unsigned long class; 208 u32 classid; 209 }; 210 211 struct tcf_proto_ops { 212 struct list_head head; 213 char kind[IFNAMSIZ]; 214 215 int (*classify)(struct sk_buff *, 216 const struct tcf_proto *, 217 struct tcf_result *); 218 int (*init)(struct tcf_proto*); 219 bool (*destroy)(struct tcf_proto*, bool); 220 221 unsigned long (*get)(struct tcf_proto*, u32 handle); 222 int (*change)(struct net *net, struct sk_buff *, 223 struct tcf_proto*, unsigned long, 224 u32 handle, struct nlattr **, 225 unsigned long *, bool); 226 int (*delete)(struct tcf_proto*, unsigned long); 227 void (*walk)(struct tcf_proto*, struct tcf_walker *arg); 228 229 /* rtnetlink specific */ 230 int (*dump)(struct net*, struct tcf_proto*, unsigned long, 231 struct sk_buff *skb, struct tcmsg*); 232 233 struct module *owner; 234 }; 235 236 struct tcf_proto { 237 /* Fast access part */ 238 struct tcf_proto __rcu *next; 239 void __rcu *root; 240 int (*classify)(struct sk_buff *, 241 const struct tcf_proto *, 242 struct tcf_result *); 243 __be16 protocol; 244 245 /* All the rest */ 246 u32 prio; 247 u32 classid; 248 struct Qdisc *q; 249 void *data; 250 const struct tcf_proto_ops *ops; 251 struct rcu_head rcu; 252 }; 253 254 struct qdisc_skb_cb { 255 unsigned int pkt_len; 256 u16 slave_dev_queue_mapping; 257 u16 tc_classid; 258 #define QDISC_CB_PRIV_LEN 20 259 unsigned char data[QDISC_CB_PRIV_LEN]; 260 }; 261 262 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz) 263 { 264 struct qdisc_skb_cb *qcb; 265 266 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz); 267 BUILD_BUG_ON(sizeof(qcb->data) < sz); 268 } 269 270 static inline int qdisc_qlen(const struct Qdisc *q) 271 { 272 return q->q.qlen; 273 } 274 275 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb) 276 { 277 return (struct qdisc_skb_cb *)skb->cb; 278 } 279 280 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc) 281 { 282 return &qdisc->q.lock; 283 } 284 285 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc) 286 { 287 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc); 288 289 return q; 290 } 291 292 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc) 293 { 294 return qdisc->dev_queue->qdisc_sleeping; 295 } 296 297 /* The qdisc root lock is a mechanism by which to top level 298 * of a qdisc tree can be locked from any qdisc node in the 299 * forest. This allows changing the configuration of some 300 * aspect of the qdisc tree while blocking out asynchronous 301 * qdisc access in the packet processing paths. 302 * 303 * It is only legal to do this when the root will not change 304 * on us. Otherwise we'll potentially lock the wrong qdisc 305 * root. This is enforced by holding the RTNL semaphore, which 306 * all users of this lock accessor must do. 307 */ 308 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc) 309 { 310 struct Qdisc *root = qdisc_root(qdisc); 311 312 ASSERT_RTNL(); 313 return qdisc_lock(root); 314 } 315 316 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc) 317 { 318 struct Qdisc *root = qdisc_root_sleeping(qdisc); 319 320 ASSERT_RTNL(); 321 return qdisc_lock(root); 322 } 323 324 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc) 325 { 326 return qdisc->dev_queue->dev; 327 } 328 329 static inline void sch_tree_lock(const struct Qdisc *q) 330 { 331 spin_lock_bh(qdisc_root_sleeping_lock(q)); 332 } 333 334 static inline void sch_tree_unlock(const struct Qdisc *q) 335 { 336 spin_unlock_bh(qdisc_root_sleeping_lock(q)); 337 } 338 339 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q) 340 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q) 341 342 extern struct Qdisc noop_qdisc; 343 extern struct Qdisc_ops noop_qdisc_ops; 344 extern struct Qdisc_ops pfifo_fast_ops; 345 extern struct Qdisc_ops mq_qdisc_ops; 346 extern struct Qdisc_ops noqueue_qdisc_ops; 347 extern const struct Qdisc_ops *default_qdisc_ops; 348 static inline const struct Qdisc_ops * 349 get_default_qdisc_ops(const struct net_device *dev, int ntx) 350 { 351 return ntx < dev->real_num_tx_queues ? 352 default_qdisc_ops : &pfifo_fast_ops; 353 } 354 355 struct Qdisc_class_common { 356 u32 classid; 357 struct hlist_node hnode; 358 }; 359 360 struct Qdisc_class_hash { 361 struct hlist_head *hash; 362 unsigned int hashsize; 363 unsigned int hashmask; 364 unsigned int hashelems; 365 }; 366 367 static inline unsigned int qdisc_class_hash(u32 id, u32 mask) 368 { 369 id ^= id >> 8; 370 id ^= id >> 4; 371 return id & mask; 372 } 373 374 static inline struct Qdisc_class_common * 375 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id) 376 { 377 struct Qdisc_class_common *cl; 378 unsigned int h; 379 380 h = qdisc_class_hash(id, hash->hashmask); 381 hlist_for_each_entry(cl, &hash->hash[h], hnode) { 382 if (cl->classid == id) 383 return cl; 384 } 385 return NULL; 386 } 387 388 int qdisc_class_hash_init(struct Qdisc_class_hash *); 389 void qdisc_class_hash_insert(struct Qdisc_class_hash *, 390 struct Qdisc_class_common *); 391 void qdisc_class_hash_remove(struct Qdisc_class_hash *, 392 struct Qdisc_class_common *); 393 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *); 394 void qdisc_class_hash_destroy(struct Qdisc_class_hash *); 395 396 void dev_init_scheduler(struct net_device *dev); 397 void dev_shutdown(struct net_device *dev); 398 void dev_activate(struct net_device *dev); 399 void dev_deactivate(struct net_device *dev); 400 void dev_deactivate_many(struct list_head *head); 401 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, 402 struct Qdisc *qdisc); 403 void qdisc_reset(struct Qdisc *qdisc); 404 void qdisc_destroy(struct Qdisc *qdisc); 405 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n, 406 unsigned int len); 407 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, 408 const struct Qdisc_ops *ops); 409 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, 410 const struct Qdisc_ops *ops, u32 parentid); 411 void __qdisc_calculate_pkt_len(struct sk_buff *skb, 412 const struct qdisc_size_table *stab); 413 bool tcf_destroy(struct tcf_proto *tp, bool force); 414 void tcf_destroy_chain(struct tcf_proto __rcu **fl); 415 int skb_do_redirect(struct sk_buff *); 416 417 static inline bool skb_at_tc_ingress(const struct sk_buff *skb) 418 { 419 #ifdef CONFIG_NET_CLS_ACT 420 return G_TC_AT(skb->tc_verd) & AT_INGRESS; 421 #else 422 return false; 423 #endif 424 } 425 426 /* Reset all TX qdiscs greater then index of a device. */ 427 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i) 428 { 429 struct Qdisc *qdisc; 430 431 for (; i < dev->num_tx_queues; i++) { 432 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc); 433 if (qdisc) { 434 spin_lock_bh(qdisc_lock(qdisc)); 435 qdisc_reset(qdisc); 436 spin_unlock_bh(qdisc_lock(qdisc)); 437 } 438 } 439 } 440 441 static inline void qdisc_reset_all_tx(struct net_device *dev) 442 { 443 qdisc_reset_all_tx_gt(dev, 0); 444 } 445 446 /* Are all TX queues of the device empty? */ 447 static inline bool qdisc_all_tx_empty(const struct net_device *dev) 448 { 449 unsigned int i; 450 451 rcu_read_lock(); 452 for (i = 0; i < dev->num_tx_queues; i++) { 453 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 454 const struct Qdisc *q = rcu_dereference(txq->qdisc); 455 456 if (q->q.qlen) { 457 rcu_read_unlock(); 458 return false; 459 } 460 } 461 rcu_read_unlock(); 462 return true; 463 } 464 465 /* Are any of the TX qdiscs changing? */ 466 static inline bool qdisc_tx_changing(const struct net_device *dev) 467 { 468 unsigned int i; 469 470 for (i = 0; i < dev->num_tx_queues; i++) { 471 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 472 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping) 473 return true; 474 } 475 return false; 476 } 477 478 /* Is the device using the noop qdisc on all queues? */ 479 static inline bool qdisc_tx_is_noop(const struct net_device *dev) 480 { 481 unsigned int i; 482 483 for (i = 0; i < dev->num_tx_queues; i++) { 484 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 485 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc) 486 return false; 487 } 488 return true; 489 } 490 491 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb) 492 { 493 return qdisc_skb_cb(skb)->pkt_len; 494 } 495 496 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */ 497 enum net_xmit_qdisc_t { 498 __NET_XMIT_STOLEN = 0x00010000, 499 __NET_XMIT_BYPASS = 0x00020000, 500 }; 501 502 #ifdef CONFIG_NET_CLS_ACT 503 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1) 504 #else 505 #define net_xmit_drop_count(e) (1) 506 #endif 507 508 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb, 509 const struct Qdisc *sch) 510 { 511 #ifdef CONFIG_NET_SCHED 512 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab); 513 514 if (stab) 515 __qdisc_calculate_pkt_len(skb, stab); 516 #endif 517 } 518 519 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch) 520 { 521 qdisc_calculate_pkt_len(skb, sch); 522 return sch->enqueue(skb, sch); 523 } 524 525 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q) 526 { 527 return q->flags & TCQ_F_CPUSTATS; 528 } 529 530 static inline void bstats_update(struct gnet_stats_basic_packed *bstats, 531 const struct sk_buff *skb) 532 { 533 bstats->bytes += qdisc_pkt_len(skb); 534 bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1; 535 } 536 537 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats, 538 const struct sk_buff *skb) 539 { 540 u64_stats_update_begin(&bstats->syncp); 541 bstats_update(&bstats->bstats, skb); 542 u64_stats_update_end(&bstats->syncp); 543 } 544 545 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch, 546 const struct sk_buff *skb) 547 { 548 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb); 549 } 550 551 static inline void qdisc_bstats_update(struct Qdisc *sch, 552 const struct sk_buff *skb) 553 { 554 bstats_update(&sch->bstats, skb); 555 } 556 557 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch, 558 const struct sk_buff *skb) 559 { 560 sch->qstats.backlog -= qdisc_pkt_len(skb); 561 } 562 563 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch, 564 const struct sk_buff *skb) 565 { 566 sch->qstats.backlog += qdisc_pkt_len(skb); 567 } 568 569 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count) 570 { 571 sch->qstats.drops += count; 572 } 573 574 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats) 575 { 576 qstats->drops++; 577 } 578 579 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats) 580 { 581 qstats->overlimits++; 582 } 583 584 static inline void qdisc_qstats_drop(struct Qdisc *sch) 585 { 586 qstats_drop_inc(&sch->qstats); 587 } 588 589 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch) 590 { 591 qstats_drop_inc(this_cpu_ptr(sch->cpu_qstats)); 592 } 593 594 static inline void qdisc_qstats_overlimit(struct Qdisc *sch) 595 { 596 sch->qstats.overlimits++; 597 } 598 599 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch, 600 struct sk_buff_head *list) 601 { 602 __skb_queue_tail(list, skb); 603 qdisc_qstats_backlog_inc(sch, skb); 604 605 return NET_XMIT_SUCCESS; 606 } 607 608 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch) 609 { 610 return __qdisc_enqueue_tail(skb, sch, &sch->q); 611 } 612 613 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch, 614 struct sk_buff_head *list) 615 { 616 struct sk_buff *skb = __skb_dequeue(list); 617 618 if (likely(skb != NULL)) { 619 qdisc_qstats_backlog_dec(sch, skb); 620 qdisc_bstats_update(sch, skb); 621 } 622 623 return skb; 624 } 625 626 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch) 627 { 628 return __qdisc_dequeue_head(sch, &sch->q); 629 } 630 631 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch, 632 struct sk_buff_head *list) 633 { 634 struct sk_buff *skb = __skb_dequeue(list); 635 636 if (likely(skb != NULL)) { 637 unsigned int len = qdisc_pkt_len(skb); 638 qdisc_qstats_backlog_dec(sch, skb); 639 kfree_skb(skb); 640 return len; 641 } 642 643 return 0; 644 } 645 646 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch) 647 { 648 return __qdisc_queue_drop_head(sch, &sch->q); 649 } 650 651 static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch, 652 struct sk_buff_head *list) 653 { 654 struct sk_buff *skb = __skb_dequeue_tail(list); 655 656 if (likely(skb != NULL)) 657 qdisc_qstats_backlog_dec(sch, skb); 658 659 return skb; 660 } 661 662 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch) 663 { 664 return __qdisc_dequeue_tail(sch, &sch->q); 665 } 666 667 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch) 668 { 669 return skb_peek(&sch->q); 670 } 671 672 /* generic pseudo peek method for non-work-conserving qdisc */ 673 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch) 674 { 675 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */ 676 if (!sch->gso_skb) { 677 sch->gso_skb = sch->dequeue(sch); 678 if (sch->gso_skb) 679 /* it's still part of the queue */ 680 sch->q.qlen++; 681 } 682 683 return sch->gso_skb; 684 } 685 686 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */ 687 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch) 688 { 689 struct sk_buff *skb = sch->gso_skb; 690 691 if (skb) { 692 sch->gso_skb = NULL; 693 sch->q.qlen--; 694 } else { 695 skb = sch->dequeue(sch); 696 } 697 698 return skb; 699 } 700 701 static inline void __qdisc_reset_queue(struct Qdisc *sch, 702 struct sk_buff_head *list) 703 { 704 /* 705 * We do not know the backlog in bytes of this list, it 706 * is up to the caller to correct it 707 */ 708 __skb_queue_purge(list); 709 } 710 711 static inline void qdisc_reset_queue(struct Qdisc *sch) 712 { 713 __qdisc_reset_queue(sch, &sch->q); 714 sch->qstats.backlog = 0; 715 } 716 717 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, 718 struct Qdisc **pold) 719 { 720 struct Qdisc *old; 721 722 sch_tree_lock(sch); 723 old = *pold; 724 *pold = new; 725 if (old != NULL) { 726 qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog); 727 qdisc_reset(old); 728 } 729 sch_tree_unlock(sch); 730 731 return old; 732 } 733 734 static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch, 735 struct sk_buff_head *list) 736 { 737 struct sk_buff *skb = __qdisc_dequeue_tail(sch, list); 738 739 if (likely(skb != NULL)) { 740 unsigned int len = qdisc_pkt_len(skb); 741 kfree_skb(skb); 742 return len; 743 } 744 745 return 0; 746 } 747 748 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch) 749 { 750 return __qdisc_queue_drop(sch, &sch->q); 751 } 752 753 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch) 754 { 755 kfree_skb(skb); 756 qdisc_qstats_drop(sch); 757 758 return NET_XMIT_DROP; 759 } 760 761 static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch) 762 { 763 qdisc_qstats_drop(sch); 764 765 #ifdef CONFIG_NET_CLS_ACT 766 if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch)) 767 goto drop; 768 769 return NET_XMIT_SUCCESS; 770 771 drop: 772 #endif 773 kfree_skb(skb); 774 return NET_XMIT_DROP; 775 } 776 777 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how 778 long it will take to send a packet given its size. 779 */ 780 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen) 781 { 782 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead; 783 if (slot < 0) 784 slot = 0; 785 slot >>= rtab->rate.cell_log; 786 if (slot > 255) 787 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF]; 788 return rtab->data[slot]; 789 } 790 791 struct psched_ratecfg { 792 u64 rate_bytes_ps; /* bytes per second */ 793 u32 mult; 794 u16 overhead; 795 u8 linklayer; 796 u8 shift; 797 }; 798 799 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r, 800 unsigned int len) 801 { 802 len += r->overhead; 803 804 if (unlikely(r->linklayer == TC_LINKLAYER_ATM)) 805 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift; 806 807 return ((u64)len * r->mult) >> r->shift; 808 } 809 810 void psched_ratecfg_precompute(struct psched_ratecfg *r, 811 const struct tc_ratespec *conf, 812 u64 rate64); 813 814 static inline void psched_ratecfg_getrate(struct tc_ratespec *res, 815 const struct psched_ratecfg *r) 816 { 817 memset(res, 0, sizeof(*res)); 818 819 /* legacy struct tc_ratespec has a 32bit @rate field 820 * Qdisc using 64bit rate should add new attributes 821 * in order to maintain compatibility. 822 */ 823 res->rate = min_t(u64, r->rate_bytes_ps, ~0U); 824 825 res->overhead = r->overhead; 826 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK); 827 } 828 829 #endif 830