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Linux 4.14.215
[linux/fpc-iii.git] / include / net / sch_generic.h
blob37876d842f2e6c587f7ade97c02c495410e61371
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_SCHED_GENERIC_H
3 #define __NET_SCHED_GENERIC_H
4
5 #include <linux/netdevice.h>
6 #include <linux/types.h>
7 #include <linux/rcupdate.h>
8 #include <linux/pkt_sched.h>
9 #include <linux/pkt_cls.h>
10 #include <linux/percpu.h>
11 #include <linux/dynamic_queue_limits.h>
12 #include <linux/list.h>
13 #include <linux/refcount.h>
14 #include <linux/workqueue.h>
15 #include <net/gen_stats.h>
16 #include <net/rtnetlink.h>
17
18 struct Qdisc_ops;
19 struct qdisc_walker;
20 struct tcf_walker;
21 struct module;
22
23 struct qdisc_rate_table {
24 struct tc_ratespec rate;
25 u32 data[256];
26 struct qdisc_rate_table *next;
27 int refcnt;
28 };
29
30 enum qdisc_state_t {
31 __QDISC_STATE_SCHED,
32 __QDISC_STATE_DEACTIVATED,
33 };
34
35 struct qdisc_size_table {
36 struct rcu_head rcu;
37 struct list_head list;
38 struct tc_sizespec szopts;
39 int refcnt;
40 u16 data[];
41 };
42
43 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
44 struct qdisc_skb_head {
45 struct sk_buff *head;
46 struct sk_buff *tail;
47 __u32 qlen;
48 spinlock_t lock;
49 };
50
51 struct Qdisc {
52 int (*enqueue)(struct sk_buff *skb,
53 struct Qdisc *sch,
54 struct sk_buff **to_free);
55 struct sk_buff * (*dequeue)(struct Qdisc *sch);
56 unsigned int flags;
57 #define TCQ_F_BUILTIN 1
58 #define TCQ_F_INGRESS 2
59 #define TCQ_F_CAN_BYPASS 4
60 #define TCQ_F_MQROOT 8
61 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
62 * q->dev_queue : It can test
63 * netif_xmit_frozen_or_stopped() before
64 * dequeueing next packet.
65 * Its true for MQ/MQPRIO slaves, or non
66 * multiqueue device.
67 */
68 #define TCQ_F_WARN_NONWC (1 << 16)
69 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
70 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
71 * qdisc_tree_decrease_qlen() should stop.
72 */
73 #define TCQ_F_INVISIBLE 0x80 /* invisible by default in dump */
74 u32 limit;
75 const struct Qdisc_ops *ops;
76 struct qdisc_size_table __rcu *stab;
77 struct hlist_node hash;
78 u32 handle;
79 u32 parent;
80
81 struct netdev_queue *dev_queue;
82
83 struct net_rate_estimator __rcu *rate_est;
84 struct gnet_stats_basic_cpu __percpu *cpu_bstats;
85 struct gnet_stats_queue __percpu *cpu_qstats;
86
87 /*
88 * For performance sake on SMP, we put highly modified fields at the end
89 */
90 struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
91 struct qdisc_skb_head q;
92 struct gnet_stats_basic_packed bstats;
93 seqcount_t running;
94 struct gnet_stats_queue qstats;
95 unsigned long state;
96 struct Qdisc *next_sched;
97 struct sk_buff *skb_bad_txq;
98 struct rcu_head rcu_head;
99 int padded;
100 refcount_t refcnt;
101
102 spinlock_t busylock ____cacheline_aligned_in_smp;
103 };
104
105 static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
106 {
107 if (qdisc->flags & TCQ_F_BUILTIN)
108 return;
109 refcount_inc(&qdisc->refcnt);
110 }
111
112 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
113 {
114 return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
115 }
116
117 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
118 {
119 if (qdisc_is_running(qdisc))
120 return false;
121 /* Variant of write_seqcount_begin() telling lockdep a trylock
122 * was attempted.
123 */
124 raw_write_seqcount_begin(&qdisc->running);
125 seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
126 return true;
127 }
128
129 static inline void qdisc_run_end(struct Qdisc *qdisc)
130 {
131 write_seqcount_end(&qdisc->running);
132 }
133
134 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
135 {
136 return qdisc->flags & TCQ_F_ONETXQUEUE;
137 }
138
139 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
140 {
141 #ifdef CONFIG_BQL
142 /* Non-BQL migrated drivers will return 0, too. */
143 return dql_avail(&txq->dql);
144 #else
145 return 0;
146 #endif
147 }
148
149 struct Qdisc_class_ops {
150 /* Child qdisc manipulation */
151 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
152 int (*graft)(struct Qdisc *, unsigned long cl,
153 struct Qdisc *, struct Qdisc **);
154 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
155 void (*qlen_notify)(struct Qdisc *, unsigned long);
156
157 /* Class manipulation routines */
158 unsigned long (*find)(struct Qdisc *, u32 classid);
159 int (*change)(struct Qdisc *, u32, u32,
160 struct nlattr **, unsigned long *);
161 int (*delete)(struct Qdisc *, unsigned long);
162 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
163
164 /* Filter manipulation */
165 struct tcf_block * (*tcf_block)(struct Qdisc *, unsigned long);
166 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
167 u32 classid);
168 void (*unbind_tcf)(struct Qdisc *, unsigned long);
169
170 /* rtnetlink specific */
171 int (*dump)(struct Qdisc *, unsigned long,
172 struct sk_buff *skb, struct tcmsg*);
173 int (*dump_stats)(struct Qdisc *, unsigned long,
174 struct gnet_dump *);
175 };
176
177 struct Qdisc_ops {
178 struct Qdisc_ops *next;
179 const struct Qdisc_class_ops *cl_ops;
180 char id[IFNAMSIZ];
181 int priv_size;
182
183 int (*enqueue)(struct sk_buff *skb,
184 struct Qdisc *sch,
185 struct sk_buff **to_free);
186 struct sk_buff * (*dequeue)(struct Qdisc *);
187 struct sk_buff * (*peek)(struct Qdisc *);
188
189 int (*init)(struct Qdisc *, struct nlattr *arg);
190 void (*reset)(struct Qdisc *);
191 void (*destroy)(struct Qdisc *);
192 int (*change)(struct Qdisc *, struct nlattr *arg);
193 void (*attach)(struct Qdisc *);
194
195 int (*dump)(struct Qdisc *, struct sk_buff *);
196 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
197
198 struct module *owner;
199 };
200
201
202 struct tcf_result {
203 union {
204 struct {
205 unsigned long class;
206 u32 classid;
207 };
208 const struct tcf_proto *goto_tp;
209 };
210 };
211
212 struct tcf_proto_ops {
213 struct list_head head;
214 char kind[IFNAMSIZ];
215
216 int (*classify)(struct sk_buff *,
217 const struct tcf_proto *,
218 struct tcf_result *);
219 int (*init)(struct tcf_proto*);
220 void (*destroy)(struct tcf_proto*);
221
222 void* (*get)(struct tcf_proto*, u32 handle);
223 int (*change)(struct net *net, struct sk_buff *,
224 struct tcf_proto*, unsigned long,
225 u32 handle, struct nlattr **,
226 void **, bool);
227 int (*delete)(struct tcf_proto*, void *, bool*);
228 void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
229 void (*bind_class)(void *, u32, unsigned long);
230
231 /* rtnetlink specific */
232 int (*dump)(struct net*, struct tcf_proto*, void *,
233 struct sk_buff *skb, struct tcmsg*);
234
235 struct module *owner;
236 };
237
238 struct tcf_proto {
239 /* Fast access part */
240 struct tcf_proto __rcu *next;
241 void __rcu *root;
242 int (*classify)(struct sk_buff *,
243 const struct tcf_proto *,
244 struct tcf_result *);
245 __be16 protocol;
246
247 /* All the rest */
248 u32 prio;
249 u32 classid;
250 struct Qdisc *q;
251 void *data;
252 const struct tcf_proto_ops *ops;
253 struct tcf_chain *chain;
254 struct rcu_head rcu;
255 };
256
257 struct qdisc_skb_cb {
258 unsigned int pkt_len;
259 u16 slave_dev_queue_mapping;
260 u16 tc_classid;
261 #define QDISC_CB_PRIV_LEN 20
262 unsigned char data[QDISC_CB_PRIV_LEN];
263 };
264
265 struct tcf_chain {
266 struct tcf_proto __rcu *filter_chain;
267 struct tcf_proto __rcu **p_filter_chain;
268 struct list_head list;
269 struct tcf_block *block;
270 u32 index; /* chain index */
271 unsigned int refcnt;
272 };
273
274 struct tcf_block {
275 struct list_head chain_list;
276 };
277
278 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
279 {
280 struct qdisc_skb_cb *qcb;
281
282 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
283 BUILD_BUG_ON(sizeof(qcb->data) < sz);
284 }
285
286 static inline int qdisc_qlen(const struct Qdisc *q)
287 {
288 return q->q.qlen;
289 }
290
291 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
292 {
293 return (struct qdisc_skb_cb *)skb->cb;
294 }
295
296 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
297 {
298 return &qdisc->q.lock;
299 }
300
301 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
302 {
303 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
304
305 return q;
306 }
307
308 static inline struct Qdisc *qdisc_root_bh(const struct Qdisc *qdisc)
309 {
310 return rcu_dereference_bh(qdisc->dev_queue->qdisc);
311 }
312
313 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
314 {
315 return qdisc->dev_queue->qdisc_sleeping;
316 }
317
318 /* The qdisc root lock is a mechanism by which to top level
319 * of a qdisc tree can be locked from any qdisc node in the
320 * forest. This allows changing the configuration of some
321 * aspect of the qdisc tree while blocking out asynchronous
322 * qdisc access in the packet processing paths.
323 *
324 * It is only legal to do this when the root will not change
325 * on us. Otherwise we'll potentially lock the wrong qdisc
326 * root. This is enforced by holding the RTNL semaphore, which
327 * all users of this lock accessor must do.
328 */
329 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
330 {
331 struct Qdisc *root = qdisc_root(qdisc);
332
333 ASSERT_RTNL();
334 return qdisc_lock(root);
335 }
336
337 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
338 {
339 struct Qdisc *root = qdisc_root_sleeping(qdisc);
340
341 ASSERT_RTNL();
342 return qdisc_lock(root);
343 }
344
345 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
346 {
347 struct Qdisc *root = qdisc_root_sleeping(qdisc);
348
349 ASSERT_RTNL();
350 return &root->running;
351 }
352
353 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
354 {
355 return qdisc->dev_queue->dev;
356 }
357
358 static inline void sch_tree_lock(const struct Qdisc *q)
359 {
360 spin_lock_bh(qdisc_root_sleeping_lock(q));
361 }
362
363 static inline void sch_tree_unlock(const struct Qdisc *q)
364 {
365 spin_unlock_bh(qdisc_root_sleeping_lock(q));
366 }
367
368 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
369 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
370
371 extern struct Qdisc noop_qdisc;
372 extern struct Qdisc_ops noop_qdisc_ops;
373 extern struct Qdisc_ops pfifo_fast_ops;
374 extern struct Qdisc_ops mq_qdisc_ops;
375 extern struct Qdisc_ops noqueue_qdisc_ops;
376 extern const struct Qdisc_ops *default_qdisc_ops;
377 static inline const struct Qdisc_ops *
378 get_default_qdisc_ops(const struct net_device *dev, int ntx)
379 {
380 return ntx < dev->real_num_tx_queues ?
381 default_qdisc_ops : &pfifo_fast_ops;
382 }
383
384 struct Qdisc_class_common {
385 u32 classid;
386 struct hlist_node hnode;
387 };
388
389 struct Qdisc_class_hash {
390 struct hlist_head *hash;
391 unsigned int hashsize;
392 unsigned int hashmask;
393 unsigned int hashelems;
394 };
395
396 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
397 {
398 id ^= id >> 8;
399 id ^= id >> 4;
400 return id & mask;
401 }
402
403 static inline struct Qdisc_class_common *
404 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
405 {
406 struct Qdisc_class_common *cl;
407 unsigned int h;
408
409 if (!id)
410 return NULL;
411
412 h = qdisc_class_hash(id, hash->hashmask);
413 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
414 if (cl->classid == id)
415 return cl;
416 }
417 return NULL;
418 }
419
420 int qdisc_class_hash_init(struct Qdisc_class_hash *);
421 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
422 struct Qdisc_class_common *);
423 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
424 struct Qdisc_class_common *);
425 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
426 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
427
428 void dev_init_scheduler(struct net_device *dev);
429 void dev_shutdown(struct net_device *dev);
430 void dev_activate(struct net_device *dev);
431 void dev_deactivate(struct net_device *dev);
432 void dev_deactivate_many(struct list_head *head);
433 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
434 struct Qdisc *qdisc);
435 void qdisc_reset(struct Qdisc *qdisc);
436 void qdisc_destroy(struct Qdisc *qdisc);
437 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
438 unsigned int len);
439 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
440 const struct Qdisc_ops *ops);
441 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
442 const struct Qdisc_ops *ops, u32 parentid);
443 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
444 const struct qdisc_size_table *stab);
445 int skb_do_redirect(struct sk_buff *);
446
447 static inline void skb_reset_tc(struct sk_buff *skb)
448 {
449 #ifdef CONFIG_NET_CLS_ACT
450 skb->tc_redirected = 0;
451 #endif
452 }
453
454 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
455 {
456 #ifdef CONFIG_NET_CLS_ACT
457 return skb->tc_at_ingress;
458 #else
459 return false;
460 #endif
461 }
462
463 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
464 {
465 #ifdef CONFIG_NET_CLS_ACT
466 if (skb->tc_skip_classify) {
467 skb->tc_skip_classify = 0;
468 return true;
469 }
470 #endif
471 return false;
472 }
473
474 /* Reset all TX qdiscs greater then index of a device. */
475 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
476 {
477 struct Qdisc *qdisc;
478
479 for (; i < dev->num_tx_queues; i++) {
480 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
481 if (qdisc) {
482 spin_lock_bh(qdisc_lock(qdisc));
483 qdisc_reset(qdisc);
484 spin_unlock_bh(qdisc_lock(qdisc));
485 }
486 }
487 }
488
489 static inline void qdisc_reset_all_tx(struct net_device *dev)
490 {
491 qdisc_reset_all_tx_gt(dev, 0);
492 }
493
494 /* Are all TX queues of the device empty? */
495 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
496 {
497 unsigned int i;
498
499 rcu_read_lock();
500 for (i = 0; i < dev->num_tx_queues; i++) {
501 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
502 const struct Qdisc *q = rcu_dereference(txq->qdisc);
503
504 if (q->q.qlen) {
505 rcu_read_unlock();
506 return false;
507 }
508 }
509 rcu_read_unlock();
510 return true;
511 }
512
513 /* Are any of the TX qdiscs changing? */
514 static inline bool qdisc_tx_changing(const struct net_device *dev)
515 {
516 unsigned int i;
517
518 for (i = 0; i < dev->num_tx_queues; i++) {
519 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
520 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
521 return true;
522 }
523 return false;
524 }
525
526 /* Is the device using the noop qdisc on all queues? */
527 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
528 {
529 unsigned int i;
530
531 for (i = 0; i < dev->num_tx_queues; i++) {
532 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
533 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
534 return false;
535 }
536 return true;
537 }
538
539 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
540 {
541 return qdisc_skb_cb(skb)->pkt_len;
542 }
543
544 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
545 enum net_xmit_qdisc_t {
546 __NET_XMIT_STOLEN = 0x00010000,
547 __NET_XMIT_BYPASS = 0x00020000,
548 };
549
550 #ifdef CONFIG_NET_CLS_ACT
551 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
552 #else
553 #define net_xmit_drop_count(e) (1)
554 #endif
555
556 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
557 const struct Qdisc *sch)
558 {
559 #ifdef CONFIG_NET_SCHED
560 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
561
562 if (stab)
563 __qdisc_calculate_pkt_len(skb, stab);
564 #endif
565 }
566
567 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
568 struct sk_buff **to_free)
569 {
570 qdisc_calculate_pkt_len(skb, sch);
571 return sch->enqueue(skb, sch, to_free);
572 }
573
574 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
575 {
576 return q->flags & TCQ_F_CPUSTATS;
577 }
578
579 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
580 __u64 bytes, __u32 packets)
581 {
582 bstats->bytes += bytes;
583 bstats->packets += packets;
584 }
585
586 static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
587 const struct sk_buff *skb)
588 {
589 _bstats_update(bstats,
590 qdisc_pkt_len(skb),
591 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
592 }
593
594 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
595 __u64 bytes, __u32 packets)
596 {
597 u64_stats_update_begin(&bstats->syncp);
598 _bstats_update(&bstats->bstats, bytes, packets);
599 u64_stats_update_end(&bstats->syncp);
600 }
601
602 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
603 const struct sk_buff *skb)
604 {
605 u64_stats_update_begin(&bstats->syncp);
606 bstats_update(&bstats->bstats, skb);
607 u64_stats_update_end(&bstats->syncp);
608 }
609
610 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
611 const struct sk_buff *skb)
612 {
613 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
614 }
615
616 static inline void qdisc_bstats_update(struct Qdisc *sch,
617 const struct sk_buff *skb)
618 {
619 bstats_update(&sch->bstats, skb);
620 }
621
622 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
623 const struct sk_buff *skb)
624 {
625 sch->qstats.backlog -= qdisc_pkt_len(skb);
626 }
627
628 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
629 const struct sk_buff *skb)
630 {
631 sch->qstats.backlog += qdisc_pkt_len(skb);
632 }
633
634 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
635 {
636 sch->qstats.drops += count;
637 }
638
639 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
640 {
641 qstats->drops++;
642 }
643
644 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
645 {
646 qstats->overlimits++;
647 }
648
649 static inline void qdisc_qstats_drop(struct Qdisc *sch)
650 {
651 qstats_drop_inc(&sch->qstats);
652 }
653
654 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
655 {
656 this_cpu_inc(sch->cpu_qstats->drops);
657 }
658
659 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
660 {
661 sch->qstats.overlimits++;
662 }
663
664 static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
665 {
666 qh->head = NULL;
667 qh->tail = NULL;
668 qh->qlen = 0;
669 }
670
671 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
672 struct qdisc_skb_head *qh)
673 {
674 struct sk_buff *last = qh->tail;
675
676 if (last) {
677 skb->next = NULL;
678 last->next = skb;
679 qh->tail = skb;
680 } else {
681 qh->tail = skb;
682 qh->head = skb;
683 }
684 qh->qlen++;
685 qdisc_qstats_backlog_inc(sch, skb);
686
687 return NET_XMIT_SUCCESS;
688 }
689
690 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
691 {
692 return __qdisc_enqueue_tail(skb, sch, &sch->q);
693 }
694
695 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
696 {
697 struct sk_buff *skb = qh->head;
698
699 if (likely(skb != NULL)) {
700 qh->head = skb->next;
701 qh->qlen--;
702 if (qh->head == NULL)
703 qh->tail = NULL;
704 skb->next = NULL;
705 }
706
707 return skb;
708 }
709
710 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
711 {
712 struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
713
714 if (likely(skb != NULL)) {
715 qdisc_qstats_backlog_dec(sch, skb);
716 qdisc_bstats_update(sch, skb);
717 }
718
719 return skb;
720 }
721
722 /* Instead of calling kfree_skb() while root qdisc lock is held,
723 * queue the skb for future freeing at end of __dev_xmit_skb()
724 */
725 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
726 {
727 skb->next = *to_free;
728 *to_free = skb;
729 }
730
731 static inline void __qdisc_drop_all(struct sk_buff *skb,
732 struct sk_buff **to_free)
733 {
734 if (skb->prev)
735 skb->prev->next = *to_free;
736 else
737 skb->next = *to_free;
738 *to_free = skb;
739 }
740
741 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
742 struct qdisc_skb_head *qh,
743 struct sk_buff **to_free)
744 {
745 struct sk_buff *skb = __qdisc_dequeue_head(qh);
746
747 if (likely(skb != NULL)) {
748 unsigned int len = qdisc_pkt_len(skb);
749
750 qdisc_qstats_backlog_dec(sch, skb);
751 __qdisc_drop(skb, to_free);
752 return len;
753 }
754
755 return 0;
756 }
757
758 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
759 struct sk_buff **to_free)
760 {
761 return __qdisc_queue_drop_head(sch, &sch->q, to_free);
762 }
763
764 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
765 {
766 const struct qdisc_skb_head *qh = &sch->q;
767
768 return qh->head;
769 }
770
771 /* generic pseudo peek method for non-work-conserving qdisc */
772 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
773 {
774 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
775 if (!sch->gso_skb) {
776 sch->gso_skb = sch->dequeue(sch);
777 if (sch->gso_skb) {
778 /* it's still part of the queue */
779 qdisc_qstats_backlog_inc(sch, sch->gso_skb);
780 sch->q.qlen++;
781 }
782 }
783
784 return sch->gso_skb;
785 }
786
787 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
788 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
789 {
790 struct sk_buff *skb = sch->gso_skb;
791
792 if (skb) {
793 sch->gso_skb = NULL;
794 qdisc_qstats_backlog_dec(sch, skb);
795 sch->q.qlen--;
796 } else {
797 skb = sch->dequeue(sch);
798 }
799
800 return skb;
801 }
802
803 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
804 {
805 /*
806 * We do not know the backlog in bytes of this list, it
807 * is up to the caller to correct it
808 */
809 ASSERT_RTNL();
810 if (qh->qlen) {
811 rtnl_kfree_skbs(qh->head, qh->tail);
812
813 qh->head = NULL;
814 qh->tail = NULL;
815 qh->qlen = 0;
816 }
817 }
818
819 static inline void qdisc_reset_queue(struct Qdisc *sch)
820 {
821 __qdisc_reset_queue(&sch->q);
822 sch->qstats.backlog = 0;
823 }
824
825 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
826 struct Qdisc **pold)
827 {
828 struct Qdisc *old;
829
830 sch_tree_lock(sch);
831 old = *pold;
832 *pold = new;
833 if (old != NULL) {
834 unsigned int qlen = old->q.qlen;
835 unsigned int backlog = old->qstats.backlog;
836
837 qdisc_reset(old);
838 qdisc_tree_reduce_backlog(old, qlen, backlog);
839 }
840 sch_tree_unlock(sch);
841
842 return old;
843 }
844
845 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
846 {
847 rtnl_kfree_skbs(skb, skb);
848 qdisc_qstats_drop(sch);
849 }
850
851
852 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
853 struct sk_buff **to_free)
854 {
855 __qdisc_drop(skb, to_free);
856 qdisc_qstats_drop(sch);
857
858 return NET_XMIT_DROP;
859 }
860
861 static inline int qdisc_drop_all(struct sk_buff *skb, struct Qdisc *sch,
862 struct sk_buff **to_free)
863 {
864 __qdisc_drop_all(skb, to_free);
865 qdisc_qstats_drop(sch);
866
867 return NET_XMIT_DROP;
868 }
869
870 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
871 long it will take to send a packet given its size.
872 */
873 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
874 {
875 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
876 if (slot < 0)
877 slot = 0;
878 slot >>= rtab->rate.cell_log;
879 if (slot > 255)
880 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
881 return rtab->data[slot];
882 }
883
884 struct psched_ratecfg {
885 u64 rate_bytes_ps; /* bytes per second */
886 u32 mult;
887 u16 overhead;
888 u8 linklayer;
889 u8 shift;
890 };
891
892 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
893 unsigned int len)
894 {
895 len += r->overhead;
896
897 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
898 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
899
900 return ((u64)len * r->mult) >> r->shift;
901 }
902
903 void psched_ratecfg_precompute(struct psched_ratecfg *r,
904 const struct tc_ratespec *conf,
905 u64 rate64);
906
907 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
908 const struct psched_ratecfg *r)
909 {
910 memset(res, 0, sizeof(*res));
911
912 /* legacy struct tc_ratespec has a 32bit @rate field
913 * Qdisc using 64bit rate should add new attributes
914 * in order to maintain compatibility.
915 */
916 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
917
918 res->overhead = r->overhead;
919 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
920 }
921
922 #endif
Linux with added FPC-III support