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	__QDISC_STATE_THROTTLED,
 
 30};
 31
 32/*
 33 * following bits are only changed while qdisc lock is held
 34 */
 35enum qdisc___state_t {
 36	__QDISC___STATE_RUNNING = 1,
 37};
 38
 
 
 
 
 
 
 39struct 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
 
 
 
 
 
 
 
 
 47struct 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
105static inline bool qdisc_is_running(const struct Qdisc *qdisc)
106{
107	return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
 
 
108}
109
110static 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
118static inline void qdisc_run_end(struct Qdisc *qdisc)
 
 
 
 
119{
120	qdisc->__state &= ~__QDISC___STATE_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
138static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
139{
140	return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
141}
142
143static inline void qdisc_throttled(struct Qdisc *qdisc)
144{
145	set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
146}
147
148static inline void qdisc_unthrottled(struct Qdisc *qdisc)
149{
150	clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
151}
152
153struct 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
 
 
 
 
 
 
 
182struct 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
206struct tcf_result {
207	unsigned long	class;
208	u32		classid;
 
 
 
 
 
209};
210
 
 
211struct 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
236struct 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
254struct 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
262static 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
270static inline int qdisc_qlen(const struct Qdisc *q)
271{
272	return q->q.qlen;
273}
274
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
275static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
276{
277	return (struct qdisc_skb_cb *)skb->cb;
278}
279
280static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
281{
282	return &qdisc->q.lock;
283}
284
285static 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
292static 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 */
308static 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
316static 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
324static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
325{
326	return qdisc->dev_queue->dev;
327}
328
329static inline void sch_tree_lock(const struct Qdisc *q)
330{
331	spin_lock_bh(qdisc_root_sleeping_lock(q));
 
 
 
332}
333
334static 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
342extern struct Qdisc noop_qdisc;
343extern struct Qdisc_ops noop_qdisc_ops;
344extern struct Qdisc_ops pfifo_fast_ops;
 
345extern struct Qdisc_ops mq_qdisc_ops;
346extern struct Qdisc_ops noqueue_qdisc_ops;
347extern const struct Qdisc_ops *default_qdisc_ops;
348static inline const struct Qdisc_ops *
349get_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
355struct Qdisc_class_common {
356	u32			classid;
 
357	struct hlist_node	hnode;
358};
359
360struct Qdisc_class_hash {
361	struct hlist_head	*hash;
362	unsigned int		hashsize;
363	unsigned int		hashmask;
364	unsigned int		hashelems;
365};
366
367static 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
374static inline struct Qdisc_class_common *
375qdisc_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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
388int qdisc_class_hash_init(struct Qdisc_class_hash *);
389void qdisc_class_hash_insert(struct Qdisc_class_hash *,
390			     struct Qdisc_class_common *);
391void qdisc_class_hash_remove(struct Qdisc_class_hash *,
392			     struct Qdisc_class_common *);
393void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
394void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
395
 
 
 
396void dev_init_scheduler(struct net_device *dev);
397void dev_shutdown(struct net_device *dev);
398void dev_activate(struct net_device *dev);
399void dev_deactivate(struct net_device *dev);
400void dev_deactivate_many(struct list_head *head);
401struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
402			      struct Qdisc *qdisc);
403void qdisc_reset(struct Qdisc *qdisc);
404void qdisc_destroy(struct Qdisc *qdisc);
405void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
406			       unsigned int len);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
407struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
408			  const struct Qdisc_ops *ops);
 
 
409struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
410				const struct Qdisc_ops *ops, u32 parentid);
 
411void __qdisc_calculate_pkt_len(struct sk_buff *skb,
412			       const struct qdisc_size_table *stab);
413bool tcf_destroy(struct tcf_proto *tp, bool force);
414void tcf_destroy_chain(struct tcf_proto __rcu **fl);
415int skb_do_redirect(struct sk_buff *);
416
417static 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.  */
 
 
 
 
 
 
 
 
 
 
 
427static 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
441static 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?  */
447static 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?  */
466static 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?  */
479static 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
491static 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) */
497enum 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
508static 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
519static 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
525static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
 
526{
527	return q->flags & TCQ_F_CPUSTATS;
 
 
 
528}
529
530static 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
537static 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
545static 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
551static inline void qdisc_bstats_update(struct Qdisc *sch,
552				       const struct sk_buff *skb)
553{
554	bstats_update(&sch->bstats, skb);
555}
556
557static 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
 
 
 
 
 
 
563static 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
569static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
570{
571	sch->qstats.drops += count;
572}
573
574static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
575{
576	qstats->drops++;
577}
578
579static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
580{
581	qstats->overlimits++;
582}
583
584static inline void qdisc_qstats_drop(struct Qdisc *sch)
585{
586	qstats_drop_inc(&sch->qstats);
587}
588
589static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
590{
591	qstats_drop_inc(this_cpu_ptr(sch->cpu_qstats));
592}
593
594static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
595{
596	sch->qstats.overlimits++;
597}
598
599static 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
608static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
609{
610	return __qdisc_enqueue_tail(skb, sch, &sch->q);
 
 
 
 
 
 
 
 
 
 
 
 
 
611}
612
613static 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
626static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
627{
628	return __qdisc_dequeue_head(sch, &sch->q);
629}
630
631static 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
646static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
 
 
 
 
 
 
 
 
 
 
 
647{
648	return __qdisc_queue_drop_head(sch, &sch->q);
 
 
 
649}
650
651static 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
662static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
 
663{
664	return __qdisc_dequeue_tail(sch, &sch->q);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
665}
666
667static 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 */
673static 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() */
687static 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
701static 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
711static inline void qdisc_reset_queue(struct Qdisc *sch)
712{
713	__qdisc_reset_queue(sch, &sch->q);
714	sch->qstats.backlog = 0;
715}
716
717static 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
734static 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
748static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
 
749{
750	return __qdisc_queue_drop(sch, &sch->q);
 
 
 
751}
752
753static 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
761static 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
771drop:
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 */
780static 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
791struct psched_ratecfg {
792	u64	rate_bytes_ps; /* bytes per second */
793	u32	mult;
794	u16	overhead;
 
795	u8	linklayer;
796	u8	shift;
797};
798
799static 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
810void psched_ratecfg_precompute(struct psched_ratecfg *r,
811			       const struct tc_ratespec *conf,
812			       u64 rate64);
813
814static 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