xref: /linux/include/net/sch_generic.h (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 
12 struct Qdisc_ops;
13 struct qdisc_walker;
14 struct tcf_walker;
15 struct module;
16 
17 struct qdisc_rate_table {
18 	struct tc_ratespec rate;
19 	u32		data[256];
20 	struct qdisc_rate_table *next;
21 	int		refcnt;
22 };
23 
24 enum 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  */
33 enum qdisc___state_t {
34 	__QDISC___STATE_RUNNING = 1,
35 };
36 
37 struct 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 
45 struct 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 
96 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
97 {
98 	return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
99 }
100 
101 static 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 
109 static inline void qdisc_run_end(struct Qdisc *qdisc)
110 {
111 	qdisc->__state &= ~__QDISC___STATE_RUNNING;
112 }
113 
114 static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
115 {
116 	return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
117 }
118 
119 static inline void qdisc_throttled(struct Qdisc *qdisc)
120 {
121 	set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
122 }
123 
124 static inline void qdisc_unthrottled(struct Qdisc *qdisc)
125 {
126 	clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
127 }
128 
129 struct 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 
158 struct 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 
182 struct tcf_result {
183 	unsigned long	class;
184 	u32		classid;
185 };
186 
187 struct tcf_proto_ops {
188 	struct tcf_proto_ops	*next;
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 tcf_proto*, unsigned long,
208 					struct sk_buff *skb, struct tcmsg*);
209 
210 	struct module		*owner;
211 };
212 
213 struct 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 
230 struct qdisc_skb_cb {
231 	unsigned int		pkt_len;
232 	u16			slave_dev_queue_mapping;
233 	u16			_pad;
234 	unsigned char		data[20];
235 };
236 
237 static 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 
245 static inline int qdisc_qlen(const struct Qdisc *q)
246 {
247 	return q->q.qlen;
248 }
249 
250 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
251 {
252 	return (struct qdisc_skb_cb *)skb->cb;
253 }
254 
255 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
256 {
257 	return &qdisc->q.lock;
258 }
259 
260 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
261 {
262 	return qdisc->dev_queue->qdisc;
263 }
264 
265 static 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  */
281 static 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 
289 static 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 
297 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
298 {
299 	return qdisc->dev_queue->dev;
300 }
301 
302 static inline void sch_tree_lock(const struct Qdisc *q)
303 {
304 	spin_lock_bh(qdisc_root_sleeping_lock(q));
305 }
306 
307 static 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 
315 extern struct Qdisc noop_qdisc;
316 extern struct Qdisc_ops noop_qdisc_ops;
317 extern struct Qdisc_ops pfifo_fast_ops;
318 extern struct Qdisc_ops mq_qdisc_ops;
319 extern const struct Qdisc_ops *default_qdisc_ops;
320 
321 struct Qdisc_class_common {
322 	u32			classid;
323 	struct hlist_node	hnode;
324 };
325 
326 struct Qdisc_class_hash {
327 	struct hlist_head	*hash;
328 	unsigned int		hashsize;
329 	unsigned int		hashmask;
330 	unsigned int		hashelems;
331 };
332 
333 static 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 
340 static inline struct Qdisc_class_common *
341 qdisc_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 
354 int qdisc_class_hash_init(struct Qdisc_class_hash *);
355 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
356 			     struct Qdisc_class_common *);
357 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
358 			     struct Qdisc_class_common *);
359 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
360 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
361 
362 void dev_init_scheduler(struct net_device *dev);
363 void dev_shutdown(struct net_device *dev);
364 void dev_activate(struct net_device *dev);
365 void dev_deactivate(struct net_device *dev);
366 void dev_deactivate_many(struct list_head *head);
367 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
368 			      struct Qdisc *qdisc);
369 void qdisc_reset(struct Qdisc *qdisc);
370 void qdisc_destroy(struct Qdisc *qdisc);
371 void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
372 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
373 			  const struct Qdisc_ops *ops);
374 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
375 				const struct Qdisc_ops *ops, u32 parentid);
376 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
377 			       const struct qdisc_size_table *stab);
378 void tcf_destroy(struct tcf_proto *tp);
379 void tcf_destroy_chain(struct tcf_proto **fl);
380 
381 /* Reset all TX qdiscs greater then index of a device.  */
382 static 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 
396 static 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?  */
402 static 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?  */
416 static 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?  */
428 static 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 
439 static 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) */
445 enum 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 
456 static 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 
467 static 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 
473 static 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 
480 static 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 
487 static inline void qdisc_bstats_update(struct Qdisc *sch,
488 				       const struct sk_buff *skb)
489 {
490 	bstats_update(&sch->bstats, skb);
491 }
492 
493 static 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 
502 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
503 {
504 	return __qdisc_enqueue_tail(skb, sch, &sch->q);
505 }
506 
507 static 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 
520 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
521 {
522 	return __qdisc_dequeue_head(sch, &sch->q);
523 }
524 
525 static 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 
540 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
541 {
542 	return __qdisc_queue_drop_head(sch, &sch->q);
543 }
544 
545 static 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 
556 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
557 {
558 	return __qdisc_dequeue_tail(sch, &sch->q);
559 }
560 
561 static 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 */
567 static 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() */
581 static 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 
595 static 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 
605 static inline void qdisc_reset_queue(struct Qdisc *sch)
606 {
607 	__qdisc_reset_queue(sch, &sch->q);
608 	sch->qstats.backlog = 0;
609 }
610 
611 static 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 
625 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
626 {
627 	return __qdisc_queue_drop(sch, &sch->q);
628 }
629 
630 static 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 
638 static 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 
648 drop:
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  */
657 static 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
669 static 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 
685 struct psched_ratecfg {
686 	u64	rate_bytes_ps; /* bytes per second */
687 	u32	mult;
688 	u16	overhead;
689 	u8	linklayer;
690 	u8	shift;
691 };
692 
693 static 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 
704 void psched_ratecfg_precompute(struct psched_ratecfg *r,
705 			       const struct tc_ratespec *conf,
706 			       u64 rate64);
707 
708 static 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
724