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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 <net/gen_stats.h>
10#include <net/rtnetlink.h>
11
12struct Qdisc_ops;
13struct qdisc_walker;
14struct tcf_walker;
15struct module;
16
17struct qdisc_rate_table {
18 struct tc_ratespec rate;
19 u32 data[256];
20 struct qdisc_rate_table *next;
21 int refcnt;
22};
23
24enum qdisc_state_t {
25 __QDISC_STATE_SCHED,
26 __QDISC_STATE_DEACTIVATED,
27 __QDISC_STATE_THROTTLED,
28};
29
30/*
31 * following bits are only changed while qdisc lock is held
32 */
33enum qdisc___state_t {
34 __QDISC___STATE_RUNNING = 1,
35};
36
37struct qdisc_size_table {
38 struct rcu_head rcu;
39 struct list_head list;
40 struct tc_sizespec szopts;
41 int refcnt;
42 u16 data[];
43};
44
45struct Qdisc {
46 int (*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
47 struct sk_buff * (*dequeue)(struct Qdisc *dev);
48 unsigned int flags;
49#define TCQ_F_BUILTIN 1
50#define TCQ_F_INGRESS 2
51#define TCQ_F_CAN_BYPASS 4
52#define TCQ_F_MQROOT 8
53#define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
54 * q->dev_queue : It can test
55 * netif_xmit_frozen_or_stopped() before
56 * dequeueing next packet.
57 * Its true for MQ/MQPRIO slaves, or non
58 * multiqueue device.
59 */
60#define TCQ_F_WARN_NONWC (1 << 16)
61 u32 limit;
62 const struct Qdisc_ops *ops;
63 struct qdisc_size_table __rcu *stab;
64 struct list_head list;
65 u32 handle;
66 u32 parent;
67 int (*reshape_fail)(struct sk_buff *skb,
68 struct Qdisc *q);
69
70 void *u32_node;
71
72 /* This field is deprecated, but it is still used by CBQ
73 * and it will live until better solution will be invented.
74 */
75 struct Qdisc *__parent;
76 struct netdev_queue *dev_queue;
77
78 struct gnet_stats_rate_est64 rate_est;
79 struct Qdisc *next_sched;
80 struct sk_buff *gso_skb;
81 /*
82 * For performance sake on SMP, we put highly modified fields at the end
83 */
84 unsigned long state;
85 struct sk_buff_head q;
86 struct gnet_stats_basic_packed bstats;
87 unsigned int __state;
88 struct gnet_stats_queue qstats;
89 struct rcu_head rcu_head;
90 int padded;
91 atomic_t refcnt;
92
93 spinlock_t busylock ____cacheline_aligned_in_smp;
94};
95
96static inline bool qdisc_is_running(const struct Qdisc *qdisc)
97{
98 return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
99}
100
101static inline bool qdisc_run_begin(struct Qdisc *qdisc)
102{
103 if (qdisc_is_running(qdisc))
104 return false;
105 qdisc->__state |= __QDISC___STATE_RUNNING;
106 return true;
107}
108
109static inline void qdisc_run_end(struct Qdisc *qdisc)
110{
111 qdisc->__state &= ~__QDISC___STATE_RUNNING;
112}
113
114static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
115{
116 return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
117}
118
119static inline void qdisc_throttled(struct Qdisc *qdisc)
120{
121 set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
122}
123
124static inline void qdisc_unthrottled(struct Qdisc *qdisc)
125{
126 clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
127}
128
129struct Qdisc_class_ops {
130 /* Child qdisc manipulation */
131 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
132 int (*graft)(struct Qdisc *, unsigned long cl,
133 struct Qdisc *, struct Qdisc **);
134 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
135 void (*qlen_notify)(struct Qdisc *, unsigned long);
136
137 /* Class manipulation routines */
138 unsigned long (*get)(struct Qdisc *, u32 classid);
139 void (*put)(struct Qdisc *, unsigned long);
140 int (*change)(struct Qdisc *, u32, u32,
141 struct nlattr **, unsigned long *);
142 int (*delete)(struct Qdisc *, unsigned long);
143 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
144
145 /* Filter manipulation */
146 struct tcf_proto ** (*tcf_chain)(struct Qdisc *, unsigned long);
147 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
148 u32 classid);
149 void (*unbind_tcf)(struct Qdisc *, unsigned long);
150
151 /* rtnetlink specific */
152 int (*dump)(struct Qdisc *, unsigned long,
153 struct sk_buff *skb, struct tcmsg*);
154 int (*dump_stats)(struct Qdisc *, unsigned long,
155 struct gnet_dump *);
156};
157
158struct Qdisc_ops {
159 struct Qdisc_ops *next;
160 const struct Qdisc_class_ops *cl_ops;
161 char id[IFNAMSIZ];
162 int priv_size;
163
164 int (*enqueue)(struct sk_buff *, struct Qdisc *);
165 struct sk_buff * (*dequeue)(struct Qdisc *);
166 struct sk_buff * (*peek)(struct Qdisc *);
167 unsigned int (*drop)(struct Qdisc *);
168
169 int (*init)(struct Qdisc *, struct nlattr *arg);
170 void (*reset)(struct Qdisc *);
171 void (*destroy)(struct Qdisc *);
172 int (*change)(struct Qdisc *, struct nlattr *arg);
173 void (*attach)(struct Qdisc *);
174
175 int (*dump)(struct Qdisc *, struct sk_buff *);
176 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
177
178 struct module *owner;
179};
180
181
182struct tcf_result {
183 unsigned long class;
184 u32 classid;
185};
186
187struct tcf_proto_ops {
188 struct list_head head;
189 char kind[IFNAMSIZ];
190
191 int (*classify)(struct sk_buff *,
192 const struct tcf_proto *,
193 struct tcf_result *);
194 int (*init)(struct tcf_proto*);
195 void (*destroy)(struct tcf_proto*);
196
197 unsigned long (*get)(struct tcf_proto*, u32 handle);
198 void (*put)(struct tcf_proto*, unsigned long);
199 int (*change)(struct net *net, struct sk_buff *,
200 struct tcf_proto*, unsigned long,
201 u32 handle, struct nlattr **,
202 unsigned long *);
203 int (*delete)(struct tcf_proto*, unsigned long);
204 void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
205
206 /* rtnetlink specific */
207 int (*dump)(struct net*, struct tcf_proto*, unsigned long,
208 struct sk_buff *skb, struct tcmsg*);
209
210 struct module *owner;
211};
212
213struct tcf_proto {
214 /* Fast access part */
215 struct tcf_proto *next;
216 void *root;
217 int (*classify)(struct sk_buff *,
218 const struct tcf_proto *,
219 struct tcf_result *);
220 __be16 protocol;
221
222 /* All the rest */
223 u32 prio;
224 u32 classid;
225 struct Qdisc *q;
226 void *data;
227 const struct tcf_proto_ops *ops;
228};
229
230struct qdisc_skb_cb {
231 unsigned int pkt_len;
232 u16 slave_dev_queue_mapping;
233 u16 _pad;
234 unsigned char data[20];
235};
236
237static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
238{
239 struct qdisc_skb_cb *qcb;
240
241 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
242 BUILD_BUG_ON(sizeof(qcb->data) < sz);
243}
244
245static inline int qdisc_qlen(const struct Qdisc *q)
246{
247 return q->q.qlen;
248}
249
250static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
251{
252 return (struct qdisc_skb_cb *)skb->cb;
253}
254
255static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
256{
257 return &qdisc->q.lock;
258}
259
260static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
261{
262 return qdisc->dev_queue->qdisc;
263}
264
265static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
266{
267 return qdisc->dev_queue->qdisc_sleeping;
268}
269
270/* The qdisc root lock is a mechanism by which to top level
271 * of a qdisc tree can be locked from any qdisc node in the
272 * forest. This allows changing the configuration of some
273 * aspect of the qdisc tree while blocking out asynchronous
274 * qdisc access in the packet processing paths.
275 *
276 * It is only legal to do this when the root will not change
277 * on us. Otherwise we'll potentially lock the wrong qdisc
278 * root. This is enforced by holding the RTNL semaphore, which
279 * all users of this lock accessor must do.
280 */
281static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
282{
283 struct Qdisc *root = qdisc_root(qdisc);
284
285 ASSERT_RTNL();
286 return qdisc_lock(root);
287}
288
289static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
290{
291 struct Qdisc *root = qdisc_root_sleeping(qdisc);
292
293 ASSERT_RTNL();
294 return qdisc_lock(root);
295}
296
297static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
298{
299 return qdisc->dev_queue->dev;
300}
301
302static inline void sch_tree_lock(const struct Qdisc *q)
303{
304 spin_lock_bh(qdisc_root_sleeping_lock(q));
305}
306
307static inline void sch_tree_unlock(const struct Qdisc *q)
308{
309 spin_unlock_bh(qdisc_root_sleeping_lock(q));
310}
311
312#define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
313#define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
314
315extern struct Qdisc noop_qdisc;
316extern struct Qdisc_ops noop_qdisc_ops;
317extern struct Qdisc_ops pfifo_fast_ops;
318extern struct Qdisc_ops mq_qdisc_ops;
319extern const struct Qdisc_ops *default_qdisc_ops;
320
321struct Qdisc_class_common {
322 u32 classid;
323 struct hlist_node hnode;
324};
325
326struct Qdisc_class_hash {
327 struct hlist_head *hash;
328 unsigned int hashsize;
329 unsigned int hashmask;
330 unsigned int hashelems;
331};
332
333static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
334{
335 id ^= id >> 8;
336 id ^= id >> 4;
337 return id & mask;
338}
339
340static inline struct Qdisc_class_common *
341qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
342{
343 struct Qdisc_class_common *cl;
344 unsigned int h;
345
346 h = qdisc_class_hash(id, hash->hashmask);
347 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
348 if (cl->classid == id)
349 return cl;
350 }
351 return NULL;
352}
353
354int qdisc_class_hash_init(struct Qdisc_class_hash *);
355void qdisc_class_hash_insert(struct Qdisc_class_hash *,
356 struct Qdisc_class_common *);
357void qdisc_class_hash_remove(struct Qdisc_class_hash *,
358 struct Qdisc_class_common *);
359void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
360void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
361
362void dev_init_scheduler(struct net_device *dev);
363void dev_shutdown(struct net_device *dev);
364void dev_activate(struct net_device *dev);
365void dev_deactivate(struct net_device *dev);
366void dev_deactivate_many(struct list_head *head);
367struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
368 struct Qdisc *qdisc);
369void qdisc_reset(struct Qdisc *qdisc);
370void qdisc_destroy(struct Qdisc *qdisc);
371void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
372struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
373 const struct Qdisc_ops *ops);
374struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
375 const struct Qdisc_ops *ops, u32 parentid);
376void __qdisc_calculate_pkt_len(struct sk_buff *skb,
377 const struct qdisc_size_table *stab);
378void tcf_destroy(struct tcf_proto *tp);
379void tcf_destroy_chain(struct tcf_proto **fl);
380
381/* Reset all TX qdiscs greater then index of a device. */
382static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
383{
384 struct Qdisc *qdisc;
385
386 for (; i < dev->num_tx_queues; i++) {
387 qdisc = netdev_get_tx_queue(dev, i)->qdisc;
388 if (qdisc) {
389 spin_lock_bh(qdisc_lock(qdisc));
390 qdisc_reset(qdisc);
391 spin_unlock_bh(qdisc_lock(qdisc));
392 }
393 }
394}
395
396static inline void qdisc_reset_all_tx(struct net_device *dev)
397{
398 qdisc_reset_all_tx_gt(dev, 0);
399}
400
401/* Are all TX queues of the device empty? */
402static inline bool qdisc_all_tx_empty(const struct net_device *dev)
403{
404 unsigned int i;
405 for (i = 0; i < dev->num_tx_queues; i++) {
406 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
407 const struct Qdisc *q = txq->qdisc;
408
409 if (q->q.qlen)
410 return false;
411 }
412 return true;
413}
414
415/* Are any of the TX qdiscs changing? */
416static inline bool qdisc_tx_changing(const struct net_device *dev)
417{
418 unsigned int i;
419 for (i = 0; i < dev->num_tx_queues; i++) {
420 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
421 if (txq->qdisc != txq->qdisc_sleeping)
422 return true;
423 }
424 return false;
425}
426
427/* Is the device using the noop qdisc on all queues? */
428static inline bool qdisc_tx_is_noop(const struct net_device *dev)
429{
430 unsigned int i;
431 for (i = 0; i < dev->num_tx_queues; i++) {
432 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
433 if (txq->qdisc != &noop_qdisc)
434 return false;
435 }
436 return true;
437}
438
439static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
440{
441 return qdisc_skb_cb(skb)->pkt_len;
442}
443
444/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
445enum net_xmit_qdisc_t {
446 __NET_XMIT_STOLEN = 0x00010000,
447 __NET_XMIT_BYPASS = 0x00020000,
448};
449
450#ifdef CONFIG_NET_CLS_ACT
451#define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
452#else
453#define net_xmit_drop_count(e) (1)
454#endif
455
456static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
457 const struct Qdisc *sch)
458{
459#ifdef CONFIG_NET_SCHED
460 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
461
462 if (stab)
463 __qdisc_calculate_pkt_len(skb, stab);
464#endif
465}
466
467static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
468{
469 qdisc_calculate_pkt_len(skb, sch);
470 return sch->enqueue(skb, sch);
471}
472
473static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
474{
475 qdisc_skb_cb(skb)->pkt_len = skb->len;
476 return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
477}
478
479
480static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
481 const struct sk_buff *skb)
482{
483 bstats->bytes += qdisc_pkt_len(skb);
484 bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1;
485}
486
487static inline void qdisc_bstats_update(struct Qdisc *sch,
488 const struct sk_buff *skb)
489{
490 bstats_update(&sch->bstats, skb);
491}
492
493static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
494 struct sk_buff_head *list)
495{
496 __skb_queue_tail(list, skb);
497 sch->qstats.backlog += qdisc_pkt_len(skb);
498
499 return NET_XMIT_SUCCESS;
500}
501
502static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
503{
504 return __qdisc_enqueue_tail(skb, sch, &sch->q);
505}
506
507static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
508 struct sk_buff_head *list)
509{
510 struct sk_buff *skb = __skb_dequeue(list);
511
512 if (likely(skb != NULL)) {
513 sch->qstats.backlog -= qdisc_pkt_len(skb);
514 qdisc_bstats_update(sch, skb);
515 }
516
517 return skb;
518}
519
520static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
521{
522 return __qdisc_dequeue_head(sch, &sch->q);
523}
524
525static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
526 struct sk_buff_head *list)
527{
528 struct sk_buff *skb = __skb_dequeue(list);
529
530 if (likely(skb != NULL)) {
531 unsigned int len = qdisc_pkt_len(skb);
532 sch->qstats.backlog -= len;
533 kfree_skb(skb);
534 return len;
535 }
536
537 return 0;
538}
539
540static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
541{
542 return __qdisc_queue_drop_head(sch, &sch->q);
543}
544
545static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
546 struct sk_buff_head *list)
547{
548 struct sk_buff *skb = __skb_dequeue_tail(list);
549
550 if (likely(skb != NULL))
551 sch->qstats.backlog -= qdisc_pkt_len(skb);
552
553 return skb;
554}
555
556static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
557{
558 return __qdisc_dequeue_tail(sch, &sch->q);
559}
560
561static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
562{
563 return skb_peek(&sch->q);
564}
565
566/* generic pseudo peek method for non-work-conserving qdisc */
567static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
568{
569 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
570 if (!sch->gso_skb) {
571 sch->gso_skb = sch->dequeue(sch);
572 if (sch->gso_skb)
573 /* it's still part of the queue */
574 sch->q.qlen++;
575 }
576
577 return sch->gso_skb;
578}
579
580/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
581static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
582{
583 struct sk_buff *skb = sch->gso_skb;
584
585 if (skb) {
586 sch->gso_skb = NULL;
587 sch->q.qlen--;
588 } else {
589 skb = sch->dequeue(sch);
590 }
591
592 return skb;
593}
594
595static inline void __qdisc_reset_queue(struct Qdisc *sch,
596 struct sk_buff_head *list)
597{
598 /*
599 * We do not know the backlog in bytes of this list, it
600 * is up to the caller to correct it
601 */
602 __skb_queue_purge(list);
603}
604
605static inline void qdisc_reset_queue(struct Qdisc *sch)
606{
607 __qdisc_reset_queue(sch, &sch->q);
608 sch->qstats.backlog = 0;
609}
610
611static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
612 struct sk_buff_head *list)
613{
614 struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
615
616 if (likely(skb != NULL)) {
617 unsigned int len = qdisc_pkt_len(skb);
618 kfree_skb(skb);
619 return len;
620 }
621
622 return 0;
623}
624
625static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
626{
627 return __qdisc_queue_drop(sch, &sch->q);
628}
629
630static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
631{
632 kfree_skb(skb);
633 sch->qstats.drops++;
634
635 return NET_XMIT_DROP;
636}
637
638static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
639{
640 sch->qstats.drops++;
641
642#ifdef CONFIG_NET_CLS_ACT
643 if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
644 goto drop;
645
646 return NET_XMIT_SUCCESS;
647
648drop:
649#endif
650 kfree_skb(skb);
651 return NET_XMIT_DROP;
652}
653
654/* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
655 long it will take to send a packet given its size.
656 */
657static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
658{
659 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
660 if (slot < 0)
661 slot = 0;
662 slot >>= rtab->rate.cell_log;
663 if (slot > 255)
664 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
665 return rtab->data[slot];
666}
667
668#ifdef CONFIG_NET_CLS_ACT
669static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask,
670 int action)
671{
672 struct sk_buff *n;
673
674 n = skb_clone(skb, gfp_mask);
675
676 if (n) {
677 n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
678 n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
679 n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
680 }
681 return n;
682}
683#endif
684
685struct psched_ratecfg {
686 u64 rate_bytes_ps; /* bytes per second */
687 u32 mult;
688 u16 overhead;
689 u8 linklayer;
690 u8 shift;
691};
692
693static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
694 unsigned int len)
695{
696 len += r->overhead;
697
698 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
699 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
700
701 return ((u64)len * r->mult) >> r->shift;
702}
703
704void psched_ratecfg_precompute(struct psched_ratecfg *r,
705 const struct tc_ratespec *conf,
706 u64 rate64);
707
708static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
709 const struct psched_ratecfg *r)
710{
711 memset(res, 0, sizeof(*res));
712
713 /* legacy struct tc_ratespec has a 32bit @rate field
714 * Qdisc using 64bit rate should add new attributes
715 * in order to maintain compatibility.
716 */
717 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
718
719 res->overhead = r->overhead;
720 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
721}
722
723#endif
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
14struct Qdisc_ops;
15struct qdisc_walker;
16struct tcf_walker;
17struct module;
18
19struct qdisc_rate_table {
20 struct tc_ratespec rate;
21 u32 data[256];
22 struct qdisc_rate_table *next;
23 int refcnt;
24};
25
26enum qdisc_state_t {
27 __QDISC_STATE_SCHED,
28 __QDISC_STATE_DEACTIVATED,
29};
30
31struct qdisc_size_table {
32 struct rcu_head rcu;
33 struct list_head list;
34 struct tc_sizespec szopts;
35 int refcnt;
36 u16 data[];
37};
38
39/* similar to sk_buff_head, but skb->prev pointer is undefined. */
40struct qdisc_skb_head {
41 struct sk_buff *head;
42 struct sk_buff *tail;
43 __u32 qlen;
44 spinlock_t lock;
45};
46
47struct Qdisc {
48 int (*enqueue)(struct sk_buff *skb,
49 struct Qdisc *sch,
50 struct sk_buff **to_free);
51 struct sk_buff * (*dequeue)(struct Qdisc *sch);
52 unsigned int flags;
53#define TCQ_F_BUILTIN 1
54#define TCQ_F_INGRESS 2
55#define TCQ_F_CAN_BYPASS 4
56#define TCQ_F_MQROOT 8
57#define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
58 * q->dev_queue : It can test
59 * netif_xmit_frozen_or_stopped() before
60 * dequeueing next packet.
61 * Its true for MQ/MQPRIO slaves, or non
62 * multiqueue device.
63 */
64#define TCQ_F_WARN_NONWC (1 << 16)
65#define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
66#define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
67 * qdisc_tree_decrease_qlen() should stop.
68 */
69 u32 limit;
70 const struct Qdisc_ops *ops;
71 struct qdisc_size_table __rcu *stab;
72 struct hlist_node hash;
73 u32 handle;
74 u32 parent;
75 void *u32_node;
76
77 struct netdev_queue *dev_queue;
78
79 struct net_rate_estimator __rcu *rate_est;
80 struct gnet_stats_basic_cpu __percpu *cpu_bstats;
81 struct gnet_stats_queue __percpu *cpu_qstats;
82
83 /*
84 * For performance sake on SMP, we put highly modified fields at the end
85 */
86 struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
87 struct qdisc_skb_head q;
88 struct gnet_stats_basic_packed bstats;
89 seqcount_t running;
90 struct gnet_stats_queue qstats;
91 unsigned long state;
92 struct Qdisc *next_sched;
93 struct sk_buff *skb_bad_txq;
94 struct rcu_head rcu_head;
95 int padded;
96 atomic_t refcnt;
97
98 spinlock_t busylock ____cacheline_aligned_in_smp;
99};
100
101static inline bool qdisc_is_running(const struct Qdisc *qdisc)
102{
103 return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
104}
105
106static inline bool qdisc_run_begin(struct Qdisc *qdisc)
107{
108 if (qdisc_is_running(qdisc))
109 return false;
110 /* Variant of write_seqcount_begin() telling lockdep a trylock
111 * was attempted.
112 */
113 raw_write_seqcount_begin(&qdisc->running);
114 seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
115 return true;
116}
117
118static inline void qdisc_run_end(struct Qdisc *qdisc)
119{
120 write_seqcount_end(&qdisc->running);
121}
122
123static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
124{
125 return qdisc->flags & TCQ_F_ONETXQUEUE;
126}
127
128static 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
138struct Qdisc_class_ops {
139 /* Child qdisc manipulation */
140 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
141 int (*graft)(struct Qdisc *, unsigned long cl,
142 struct Qdisc *, struct Qdisc **);
143 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
144 void (*qlen_notify)(struct Qdisc *, unsigned long);
145
146 /* Class manipulation routines */
147 unsigned long (*get)(struct Qdisc *, u32 classid);
148 void (*put)(struct Qdisc *, unsigned long);
149 int (*change)(struct Qdisc *, u32, u32,
150 struct nlattr **, unsigned long *);
151 int (*delete)(struct Qdisc *, unsigned long);
152 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
153
154 /* Filter manipulation */
155 struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long);
156 bool (*tcf_cl_offload)(u32 classid);
157 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
158 u32 classid);
159 void (*unbind_tcf)(struct Qdisc *, unsigned long);
160
161 /* rtnetlink specific */
162 int (*dump)(struct Qdisc *, unsigned long,
163 struct sk_buff *skb, struct tcmsg*);
164 int (*dump_stats)(struct Qdisc *, unsigned long,
165 struct gnet_dump *);
166};
167
168struct Qdisc_ops {
169 struct Qdisc_ops *next;
170 const struct Qdisc_class_ops *cl_ops;
171 char id[IFNAMSIZ];
172 int priv_size;
173
174 int (*enqueue)(struct sk_buff *skb,
175 struct Qdisc *sch,
176 struct sk_buff **to_free);
177 struct sk_buff * (*dequeue)(struct Qdisc *);
178 struct sk_buff * (*peek)(struct Qdisc *);
179
180 int (*init)(struct Qdisc *, struct nlattr *arg);
181 void (*reset)(struct Qdisc *);
182 void (*destroy)(struct Qdisc *);
183 int (*change)(struct Qdisc *, struct nlattr *arg);
184 void (*attach)(struct Qdisc *);
185
186 int (*dump)(struct Qdisc *, struct sk_buff *);
187 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
188
189 struct module *owner;
190};
191
192
193struct tcf_result {
194 unsigned long class;
195 u32 classid;
196};
197
198struct tcf_proto_ops {
199 struct list_head head;
200 char kind[IFNAMSIZ];
201
202 int (*classify)(struct sk_buff *,
203 const struct tcf_proto *,
204 struct tcf_result *);
205 int (*init)(struct tcf_proto*);
206 bool (*destroy)(struct tcf_proto*, bool);
207
208 unsigned long (*get)(struct tcf_proto*, u32 handle);
209 int (*change)(struct net *net, struct sk_buff *,
210 struct tcf_proto*, unsigned long,
211 u32 handle, struct nlattr **,
212 unsigned long *, bool);
213 int (*delete)(struct tcf_proto*, unsigned long);
214 void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
215
216 /* rtnetlink specific */
217 int (*dump)(struct net*, struct tcf_proto*, unsigned long,
218 struct sk_buff *skb, struct tcmsg*);
219
220 struct module *owner;
221};
222
223struct tcf_proto {
224 /* Fast access part */
225 struct tcf_proto __rcu *next;
226 void __rcu *root;
227 int (*classify)(struct sk_buff *,
228 const struct tcf_proto *,
229 struct tcf_result *);
230 __be16 protocol;
231
232 /* All the rest */
233 u32 prio;
234 u32 classid;
235 struct Qdisc *q;
236 void *data;
237 const struct tcf_proto_ops *ops;
238 struct rcu_head rcu;
239};
240
241struct qdisc_skb_cb {
242 unsigned int pkt_len;
243 u16 slave_dev_queue_mapping;
244 u16 tc_classid;
245#define QDISC_CB_PRIV_LEN 20
246 unsigned char data[QDISC_CB_PRIV_LEN];
247};
248
249static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
250{
251 struct qdisc_skb_cb *qcb;
252
253 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
254 BUILD_BUG_ON(sizeof(qcb->data) < sz);
255}
256
257static inline int qdisc_qlen(const struct Qdisc *q)
258{
259 return q->q.qlen;
260}
261
262static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
263{
264 return (struct qdisc_skb_cb *)skb->cb;
265}
266
267static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
268{
269 return &qdisc->q.lock;
270}
271
272static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
273{
274 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
275
276 return q;
277}
278
279static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
280{
281 return qdisc->dev_queue->qdisc_sleeping;
282}
283
284/* The qdisc root lock is a mechanism by which to top level
285 * of a qdisc tree can be locked from any qdisc node in the
286 * forest. This allows changing the configuration of some
287 * aspect of the qdisc tree while blocking out asynchronous
288 * qdisc access in the packet processing paths.
289 *
290 * It is only legal to do this when the root will not change
291 * on us. Otherwise we'll potentially lock the wrong qdisc
292 * root. This is enforced by holding the RTNL semaphore, which
293 * all users of this lock accessor must do.
294 */
295static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
296{
297 struct Qdisc *root = qdisc_root(qdisc);
298
299 ASSERT_RTNL();
300 return qdisc_lock(root);
301}
302
303static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
304{
305 struct Qdisc *root = qdisc_root_sleeping(qdisc);
306
307 ASSERT_RTNL();
308 return qdisc_lock(root);
309}
310
311static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
312{
313 struct Qdisc *root = qdisc_root_sleeping(qdisc);
314
315 ASSERT_RTNL();
316 return &root->running;
317}
318
319static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
320{
321 return qdisc->dev_queue->dev;
322}
323
324static inline void sch_tree_lock(const struct Qdisc *q)
325{
326 spin_lock_bh(qdisc_root_sleeping_lock(q));
327}
328
329static inline void sch_tree_unlock(const struct Qdisc *q)
330{
331 spin_unlock_bh(qdisc_root_sleeping_lock(q));
332}
333
334#define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
335#define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
336
337extern struct Qdisc noop_qdisc;
338extern struct Qdisc_ops noop_qdisc_ops;
339extern struct Qdisc_ops pfifo_fast_ops;
340extern struct Qdisc_ops mq_qdisc_ops;
341extern struct Qdisc_ops noqueue_qdisc_ops;
342extern const struct Qdisc_ops *default_qdisc_ops;
343static inline const struct Qdisc_ops *
344get_default_qdisc_ops(const struct net_device *dev, int ntx)
345{
346 return ntx < dev->real_num_tx_queues ?
347 default_qdisc_ops : &pfifo_fast_ops;
348}
349
350struct Qdisc_class_common {
351 u32 classid;
352 struct hlist_node hnode;
353};
354
355struct Qdisc_class_hash {
356 struct hlist_head *hash;
357 unsigned int hashsize;
358 unsigned int hashmask;
359 unsigned int hashelems;
360};
361
362static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
363{
364 id ^= id >> 8;
365 id ^= id >> 4;
366 return id & mask;
367}
368
369static inline struct Qdisc_class_common *
370qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
371{
372 struct Qdisc_class_common *cl;
373 unsigned int h;
374
375 h = qdisc_class_hash(id, hash->hashmask);
376 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
377 if (cl->classid == id)
378 return cl;
379 }
380 return NULL;
381}
382
383int qdisc_class_hash_init(struct Qdisc_class_hash *);
384void qdisc_class_hash_insert(struct Qdisc_class_hash *,
385 struct Qdisc_class_common *);
386void qdisc_class_hash_remove(struct Qdisc_class_hash *,
387 struct Qdisc_class_common *);
388void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
389void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
390
391void dev_init_scheduler(struct net_device *dev);
392void dev_shutdown(struct net_device *dev);
393void dev_activate(struct net_device *dev);
394void dev_deactivate(struct net_device *dev);
395void dev_deactivate_many(struct list_head *head);
396struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
397 struct Qdisc *qdisc);
398void qdisc_reset(struct Qdisc *qdisc);
399void qdisc_destroy(struct Qdisc *qdisc);
400void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
401 unsigned int len);
402struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
403 const struct Qdisc_ops *ops);
404struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
405 const struct Qdisc_ops *ops, u32 parentid);
406void __qdisc_calculate_pkt_len(struct sk_buff *skb,
407 const struct qdisc_size_table *stab);
408bool tcf_destroy(struct tcf_proto *tp, bool force);
409void tcf_destroy_chain(struct tcf_proto __rcu **fl);
410int skb_do_redirect(struct sk_buff *);
411
412static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
413{
414#ifdef CONFIG_NET_CLS_ACT
415 return G_TC_AT(skb->tc_verd) & AT_INGRESS;
416#else
417 return false;
418#endif
419}
420
421/* Reset all TX qdiscs greater then index of a device. */
422static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
423{
424 struct Qdisc *qdisc;
425
426 for (; i < dev->num_tx_queues; i++) {
427 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
428 if (qdisc) {
429 spin_lock_bh(qdisc_lock(qdisc));
430 qdisc_reset(qdisc);
431 spin_unlock_bh(qdisc_lock(qdisc));
432 }
433 }
434}
435
436static inline void qdisc_reset_all_tx(struct net_device *dev)
437{
438 qdisc_reset_all_tx_gt(dev, 0);
439}
440
441/* Are all TX queues of the device empty? */
442static inline bool qdisc_all_tx_empty(const struct net_device *dev)
443{
444 unsigned int i;
445
446 rcu_read_lock();
447 for (i = 0; i < dev->num_tx_queues; i++) {
448 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
449 const struct Qdisc *q = rcu_dereference(txq->qdisc);
450
451 if (q->q.qlen) {
452 rcu_read_unlock();
453 return false;
454 }
455 }
456 rcu_read_unlock();
457 return true;
458}
459
460/* Are any of the TX qdiscs changing? */
461static inline bool qdisc_tx_changing(const struct net_device *dev)
462{
463 unsigned int i;
464
465 for (i = 0; i < dev->num_tx_queues; i++) {
466 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
467 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
468 return true;
469 }
470 return false;
471}
472
473/* Is the device using the noop qdisc on all queues? */
474static inline bool qdisc_tx_is_noop(const struct net_device *dev)
475{
476 unsigned int i;
477
478 for (i = 0; i < dev->num_tx_queues; i++) {
479 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
480 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
481 return false;
482 }
483 return true;
484}
485
486static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
487{
488 return qdisc_skb_cb(skb)->pkt_len;
489}
490
491/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
492enum net_xmit_qdisc_t {
493 __NET_XMIT_STOLEN = 0x00010000,
494 __NET_XMIT_BYPASS = 0x00020000,
495};
496
497#ifdef CONFIG_NET_CLS_ACT
498#define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
499#else
500#define net_xmit_drop_count(e) (1)
501#endif
502
503static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
504 const struct Qdisc *sch)
505{
506#ifdef CONFIG_NET_SCHED
507 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
508
509 if (stab)
510 __qdisc_calculate_pkt_len(skb, stab);
511#endif
512}
513
514static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
515 struct sk_buff **to_free)
516{
517 qdisc_calculate_pkt_len(skb, sch);
518 return sch->enqueue(skb, sch, to_free);
519}
520
521static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
522{
523 return q->flags & TCQ_F_CPUSTATS;
524}
525
526static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
527 __u64 bytes, __u32 packets)
528{
529 bstats->bytes += bytes;
530 bstats->packets += packets;
531}
532
533static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
534 const struct sk_buff *skb)
535{
536 _bstats_update(bstats,
537 qdisc_pkt_len(skb),
538 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
539}
540
541static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
542 __u64 bytes, __u32 packets)
543{
544 u64_stats_update_begin(&bstats->syncp);
545 _bstats_update(&bstats->bstats, bytes, packets);
546 u64_stats_update_end(&bstats->syncp);
547}
548
549static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
550 const struct sk_buff *skb)
551{
552 u64_stats_update_begin(&bstats->syncp);
553 bstats_update(&bstats->bstats, skb);
554 u64_stats_update_end(&bstats->syncp);
555}
556
557static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
558 const struct sk_buff *skb)
559{
560 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
561}
562
563static inline void qdisc_bstats_update(struct Qdisc *sch,
564 const struct sk_buff *skb)
565{
566 bstats_update(&sch->bstats, skb);
567}
568
569static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
570 const struct sk_buff *skb)
571{
572 sch->qstats.backlog -= qdisc_pkt_len(skb);
573}
574
575static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
576 const struct sk_buff *skb)
577{
578 sch->qstats.backlog += qdisc_pkt_len(skb);
579}
580
581static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
582{
583 sch->qstats.drops += count;
584}
585
586static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
587{
588 qstats->drops++;
589}
590
591static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
592{
593 qstats->overlimits++;
594}
595
596static inline void qdisc_qstats_drop(struct Qdisc *sch)
597{
598 qstats_drop_inc(&sch->qstats);
599}
600
601static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
602{
603 this_cpu_inc(sch->cpu_qstats->drops);
604}
605
606static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
607{
608 sch->qstats.overlimits++;
609}
610
611static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
612{
613 qh->head = NULL;
614 qh->tail = NULL;
615 qh->qlen = 0;
616}
617
618static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
619 struct qdisc_skb_head *qh)
620{
621 struct sk_buff *last = qh->tail;
622
623 if (last) {
624 skb->next = NULL;
625 last->next = skb;
626 qh->tail = skb;
627 } else {
628 qh->tail = skb;
629 qh->head = skb;
630 }
631 qh->qlen++;
632 qdisc_qstats_backlog_inc(sch, skb);
633
634 return NET_XMIT_SUCCESS;
635}
636
637static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
638{
639 return __qdisc_enqueue_tail(skb, sch, &sch->q);
640}
641
642static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
643{
644 struct sk_buff *skb = qh->head;
645
646 if (likely(skb != NULL)) {
647 qh->head = skb->next;
648 qh->qlen--;
649 if (qh->head == NULL)
650 qh->tail = NULL;
651 skb->next = NULL;
652 }
653
654 return skb;
655}
656
657static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
658{
659 struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
660
661 if (likely(skb != NULL)) {
662 qdisc_qstats_backlog_dec(sch, skb);
663 qdisc_bstats_update(sch, skb);
664 }
665
666 return skb;
667}
668
669/* Instead of calling kfree_skb() while root qdisc lock is held,
670 * queue the skb for future freeing at end of __dev_xmit_skb()
671 */
672static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
673{
674 skb->next = *to_free;
675 *to_free = skb;
676}
677
678static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
679 struct qdisc_skb_head *qh,
680 struct sk_buff **to_free)
681{
682 struct sk_buff *skb = __qdisc_dequeue_head(qh);
683
684 if (likely(skb != NULL)) {
685 unsigned int len = qdisc_pkt_len(skb);
686
687 qdisc_qstats_backlog_dec(sch, skb);
688 __qdisc_drop(skb, to_free);
689 return len;
690 }
691
692 return 0;
693}
694
695static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
696 struct sk_buff **to_free)
697{
698 return __qdisc_queue_drop_head(sch, &sch->q, to_free);
699}
700
701static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
702{
703 const struct qdisc_skb_head *qh = &sch->q;
704
705 return qh->head;
706}
707
708/* generic pseudo peek method for non-work-conserving qdisc */
709static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
710{
711 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
712 if (!sch->gso_skb) {
713 sch->gso_skb = sch->dequeue(sch);
714 if (sch->gso_skb) {
715 /* it's still part of the queue */
716 qdisc_qstats_backlog_inc(sch, sch->gso_skb);
717 sch->q.qlen++;
718 }
719 }
720
721 return sch->gso_skb;
722}
723
724/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
725static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
726{
727 struct sk_buff *skb = sch->gso_skb;
728
729 if (skb) {
730 sch->gso_skb = NULL;
731 qdisc_qstats_backlog_dec(sch, skb);
732 sch->q.qlen--;
733 } else {
734 skb = sch->dequeue(sch);
735 }
736
737 return skb;
738}
739
740static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
741{
742 /*
743 * We do not know the backlog in bytes of this list, it
744 * is up to the caller to correct it
745 */
746 ASSERT_RTNL();
747 if (qh->qlen) {
748 rtnl_kfree_skbs(qh->head, qh->tail);
749
750 qh->head = NULL;
751 qh->tail = NULL;
752 qh->qlen = 0;
753 }
754}
755
756static inline void qdisc_reset_queue(struct Qdisc *sch)
757{
758 __qdisc_reset_queue(&sch->q);
759 sch->qstats.backlog = 0;
760}
761
762static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
763 struct Qdisc **pold)
764{
765 struct Qdisc *old;
766
767 sch_tree_lock(sch);
768 old = *pold;
769 *pold = new;
770 if (old != NULL) {
771 qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog);
772 qdisc_reset(old);
773 }
774 sch_tree_unlock(sch);
775
776 return old;
777}
778
779static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
780{
781 rtnl_kfree_skbs(skb, skb);
782 qdisc_qstats_drop(sch);
783}
784
785
786static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
787 struct sk_buff **to_free)
788{
789 __qdisc_drop(skb, to_free);
790 qdisc_qstats_drop(sch);
791
792 return NET_XMIT_DROP;
793}
794
795/* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
796 long it will take to send a packet given its size.
797 */
798static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
799{
800 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
801 if (slot < 0)
802 slot = 0;
803 slot >>= rtab->rate.cell_log;
804 if (slot > 255)
805 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
806 return rtab->data[slot];
807}
808
809struct psched_ratecfg {
810 u64 rate_bytes_ps; /* bytes per second */
811 u32 mult;
812 u16 overhead;
813 u8 linklayer;
814 u8 shift;
815};
816
817static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
818 unsigned int len)
819{
820 len += r->overhead;
821
822 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
823 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
824
825 return ((u64)len * r->mult) >> r->shift;
826}
827
828void psched_ratecfg_precompute(struct psched_ratecfg *r,
829 const struct tc_ratespec *conf,
830 u64 rate64);
831
832static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
833 const struct psched_ratecfg *r)
834{
835 memset(res, 0, sizeof(*res));
836
837 /* legacy struct tc_ratespec has a 32bit @rate field
838 * Qdisc using 64bit rate should add new attributes
839 * in order to maintain compatibility.
840 */
841 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
842
843 res->overhead = r->overhead;
844 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
845}
846
847#endif