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v3.1
  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/module.h>
  8#include <linux/pkt_sched.h>
  9#include <linux/pkt_cls.h>
 
 
 10#include <net/gen_stats.h>
 11#include <net/rtnetlink.h>
 12
 13struct Qdisc_ops;
 14struct qdisc_walker;
 15struct tcf_walker;
 16struct module;
 17
 18struct qdisc_rate_table {
 19	struct tc_ratespec rate;
 20	u32		data[256];
 21	struct qdisc_rate_table *next;
 22	int		refcnt;
 23};
 24
 25enum qdisc_state_t {
 26	__QDISC_STATE_SCHED,
 27	__QDISC_STATE_DEACTIVATED,
 28	__QDISC_STATE_THROTTLED,
 29};
 30
 31/*
 32 * following bits are only changed while qdisc lock is held
 33 */
 34enum qdisc___state_t {
 35	__QDISC___STATE_RUNNING = 1,
 36};
 37
 38struct qdisc_size_table {
 39	struct rcu_head		rcu;
 40	struct list_head	list;
 41	struct tc_sizespec	szopts;
 42	int			refcnt;
 43	u16			data[];
 44};
 45
 
 
 
 
 
 
 
 
 46struct Qdisc {
 47	int 			(*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
 48	struct sk_buff *	(*dequeue)(struct Qdisc *dev);
 49	unsigned		flags;
 
 
 50#define TCQ_F_BUILTIN		1
 51#define TCQ_F_INGRESS		2
 52#define TCQ_F_CAN_BYPASS	4
 53#define TCQ_F_MQROOT		8
 
 
 
 
 
 
 
 54#define TCQ_F_WARN_NONWC	(1 << 16)
 55	int			padded;
 56	struct Qdisc_ops	*ops;
 
 
 
 
 57	struct qdisc_size_table	__rcu *stab;
 58	struct list_head	list;
 59	u32			handle;
 60	u32			parent;
 61	atomic_t		refcnt;
 62	struct gnet_stats_rate_est	rate_est;
 63	int			(*reshape_fail)(struct sk_buff *skb,
 64					struct Qdisc *q);
 65
 66	void			*u32_node;
 67
 68	/* This field is deprecated, but it is still used by CBQ
 69	 * and it will live until better solution will be invented.
 70	 */
 71	struct Qdisc		*__parent;
 72	struct netdev_queue	*dev_queue;
 73	struct Qdisc		*next_sched;
 74
 75	struct sk_buff		*gso_skb;
 
 
 
 76	/*
 77	 * For performance sake on SMP, we put highly modified fields at the end
 78	 */
 79	unsigned long		state;
 80	struct sk_buff_head	q;
 81	struct gnet_stats_basic_packed bstats;
 82	unsigned int		__state;
 83	struct gnet_stats_queue	qstats;
 
 
 
 84	struct rcu_head		rcu_head;
 85	spinlock_t		busylock;
 86	u32			limit;
 
 
 87};
 88
 89static inline bool qdisc_is_running(const struct Qdisc *qdisc)
 90{
 91	return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false;
 92}
 93
 94static inline bool qdisc_run_begin(struct Qdisc *qdisc)
 95{
 96	if (qdisc_is_running(qdisc))
 97		return false;
 98	qdisc->__state |= __QDISC___STATE_RUNNING;
 
 
 
 
 99	return true;
100}
101
102static inline void qdisc_run_end(struct Qdisc *qdisc)
103{
104	qdisc->__state &= ~__QDISC___STATE_RUNNING;
105}
106
107static inline bool qdisc_is_throttled(const struct Qdisc *qdisc)
108{
109	return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false;
110}
111
112static inline void qdisc_throttled(struct Qdisc *qdisc)
113{
114	set_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
115}
116
117static inline void qdisc_unthrottled(struct Qdisc *qdisc)
118{
119	clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state);
120}
121
122struct Qdisc_class_ops {
123	/* Child qdisc manipulation */
124	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
125	int			(*graft)(struct Qdisc *, unsigned long cl,
126					struct Qdisc *, struct Qdisc **);
127	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
128	void			(*qlen_notify)(struct Qdisc *, unsigned long);
129
130	/* Class manipulation routines */
131	unsigned long		(*get)(struct Qdisc *, u32 classid);
132	void			(*put)(struct Qdisc *, unsigned long);
133	int			(*change)(struct Qdisc *, u32, u32,
134					struct nlattr **, unsigned long *);
135	int			(*delete)(struct Qdisc *, unsigned long);
136	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
137
138	/* Filter manipulation */
139	struct tcf_proto **	(*tcf_chain)(struct Qdisc *, unsigned long);
 
140	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
141					u32 classid);
142	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
143
144	/* rtnetlink specific */
145	int			(*dump)(struct Qdisc *, unsigned long,
146					struct sk_buff *skb, struct tcmsg*);
147	int			(*dump_stats)(struct Qdisc *, unsigned long,
148					struct gnet_dump *);
149};
150
151struct Qdisc_ops {
152	struct Qdisc_ops	*next;
153	const struct Qdisc_class_ops	*cl_ops;
154	char			id[IFNAMSIZ];
155	int			priv_size;
156
157	int 			(*enqueue)(struct sk_buff *, struct Qdisc *);
 
 
158	struct sk_buff *	(*dequeue)(struct Qdisc *);
159	struct sk_buff *	(*peek)(struct Qdisc *);
160	unsigned int		(*drop)(struct Qdisc *);
161
162	int			(*init)(struct Qdisc *, struct nlattr *arg);
163	void			(*reset)(struct Qdisc *);
164	void			(*destroy)(struct Qdisc *);
165	int			(*change)(struct Qdisc *, struct nlattr *arg);
166	void			(*attach)(struct Qdisc *);
167
168	int			(*dump)(struct Qdisc *, struct sk_buff *);
169	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
170
171	struct module		*owner;
172};
173
174
175struct tcf_result {
176	unsigned long	class;
177	u32		classid;
178};
179
180struct tcf_proto_ops {
181	struct tcf_proto_ops	*next;
182	char			kind[IFNAMSIZ];
183
184	int			(*classify)(struct sk_buff *,
185					    const struct tcf_proto *,
186					    struct tcf_result *);
187	int			(*init)(struct tcf_proto*);
188	void			(*destroy)(struct tcf_proto*);
189
190	unsigned long		(*get)(struct tcf_proto*, u32 handle);
191	void			(*put)(struct tcf_proto*, unsigned long);
192	int			(*change)(struct tcf_proto*, unsigned long,
193					u32 handle, struct nlattr **,
194					unsigned long *);
195	int			(*delete)(struct tcf_proto*, unsigned long);
196	void			(*walk)(struct tcf_proto*, struct tcf_walker *arg);
197
198	/* rtnetlink specific */
199	int			(*dump)(struct tcf_proto*, unsigned long,
200					struct sk_buff *skb, struct tcmsg*);
201
202	struct module		*owner;
203};
204
205struct tcf_proto {
206	/* Fast access part */
207	struct tcf_proto	*next;
208	void			*root;
209	int			(*classify)(struct sk_buff *,
210					    const struct tcf_proto *,
211					    struct tcf_result *);
212	__be16			protocol;
213
214	/* All the rest */
215	u32			prio;
216	u32			classid;
217	struct Qdisc		*q;
218	void			*data;
219	const struct tcf_proto_ops	*ops;
 
220};
221
222struct qdisc_skb_cb {
223	unsigned int		pkt_len;
224	long			data[];
 
 
 
225};
226
227static inline int qdisc_qlen(struct Qdisc *q)
 
 
 
 
 
 
 
 
228{
229	return q->q.qlen;
230}
231
232static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
233{
234	return (struct qdisc_skb_cb *)skb->cb;
235}
236
237static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
238{
239	return &qdisc->q.lock;
240}
241
242static inline struct Qdisc *qdisc_root(struct Qdisc *qdisc)
243{
244	return qdisc->dev_queue->qdisc;
 
 
245}
246
247static inline struct Qdisc *qdisc_root_sleeping(struct Qdisc *qdisc)
248{
249	return qdisc->dev_queue->qdisc_sleeping;
250}
251
252/* The qdisc root lock is a mechanism by which to top level
253 * of a qdisc tree can be locked from any qdisc node in the
254 * forest.  This allows changing the configuration of some
255 * aspect of the qdisc tree while blocking out asynchronous
256 * qdisc access in the packet processing paths.
257 *
258 * It is only legal to do this when the root will not change
259 * on us.  Otherwise we'll potentially lock the wrong qdisc
260 * root.  This is enforced by holding the RTNL semaphore, which
261 * all users of this lock accessor must do.
262 */
263static inline spinlock_t *qdisc_root_lock(struct Qdisc *qdisc)
264{
265	struct Qdisc *root = qdisc_root(qdisc);
266
267	ASSERT_RTNL();
268	return qdisc_lock(root);
269}
270
271static inline spinlock_t *qdisc_root_sleeping_lock(struct Qdisc *qdisc)
272{
273	struct Qdisc *root = qdisc_root_sleeping(qdisc);
274
275	ASSERT_RTNL();
276	return qdisc_lock(root);
277}
278
279static inline struct net_device *qdisc_dev(struct Qdisc *qdisc)
 
 
 
 
 
 
 
 
280{
281	return qdisc->dev_queue->dev;
282}
283
284static inline void sch_tree_lock(struct Qdisc *q)
285{
286	spin_lock_bh(qdisc_root_sleeping_lock(q));
287}
288
289static inline void sch_tree_unlock(struct Qdisc *q)
290{
291	spin_unlock_bh(qdisc_root_sleeping_lock(q));
292}
293
294#define tcf_tree_lock(tp)	sch_tree_lock((tp)->q)
295#define tcf_tree_unlock(tp)	sch_tree_unlock((tp)->q)
296
297extern struct Qdisc noop_qdisc;
298extern struct Qdisc_ops noop_qdisc_ops;
299extern struct Qdisc_ops pfifo_fast_ops;
300extern struct Qdisc_ops mq_qdisc_ops;
 
 
 
 
 
 
 
 
301
302struct Qdisc_class_common {
303	u32			classid;
304	struct hlist_node	hnode;
305};
306
307struct Qdisc_class_hash {
308	struct hlist_head	*hash;
309	unsigned int		hashsize;
310	unsigned int		hashmask;
311	unsigned int		hashelems;
312};
313
314static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
315{
316	id ^= id >> 8;
317	id ^= id >> 4;
318	return id & mask;
319}
320
321static inline struct Qdisc_class_common *
322qdisc_class_find(struct Qdisc_class_hash *hash, u32 id)
323{
324	struct Qdisc_class_common *cl;
325	struct hlist_node *n;
326	unsigned int h;
327
328	h = qdisc_class_hash(id, hash->hashmask);
329	hlist_for_each_entry(cl, n, &hash->hash[h], hnode) {
330		if (cl->classid == id)
331			return cl;
332	}
333	return NULL;
334}
335
336extern int qdisc_class_hash_init(struct Qdisc_class_hash *);
337extern void qdisc_class_hash_insert(struct Qdisc_class_hash *, struct Qdisc_class_common *);
338extern void qdisc_class_hash_remove(struct Qdisc_class_hash *, struct Qdisc_class_common *);
339extern void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
340extern void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
341
342extern void dev_init_scheduler(struct net_device *dev);
343extern void dev_shutdown(struct net_device *dev);
344extern void dev_activate(struct net_device *dev);
345extern void dev_deactivate(struct net_device *dev);
346extern void dev_deactivate_many(struct list_head *head);
347extern struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
348				     struct Qdisc *qdisc);
349extern void qdisc_reset(struct Qdisc *qdisc);
350extern void qdisc_destroy(struct Qdisc *qdisc);
351extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
352extern struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
353				 struct Qdisc_ops *ops);
354extern struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
355				       struct Qdisc_ops *ops, u32 parentid);
356extern void __qdisc_calculate_pkt_len(struct sk_buff *skb,
357				      const struct qdisc_size_table *stab);
358extern void tcf_destroy(struct tcf_proto *tp);
359extern void tcf_destroy_chain(struct tcf_proto **fl);
 
 
 
 
 
 
 
 
 
 
 
 
 
360
361/* Reset all TX qdiscs greater then index of a device.  */
362static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
363{
364	struct Qdisc *qdisc;
365
366	for (; i < dev->num_tx_queues; i++) {
367		qdisc = netdev_get_tx_queue(dev, i)->qdisc;
368		if (qdisc) {
369			spin_lock_bh(qdisc_lock(qdisc));
370			qdisc_reset(qdisc);
371			spin_unlock_bh(qdisc_lock(qdisc));
372		}
373	}
374}
375
376static inline void qdisc_reset_all_tx(struct net_device *dev)
377{
378	qdisc_reset_all_tx_gt(dev, 0);
379}
380
381/* Are all TX queues of the device empty?  */
382static inline bool qdisc_all_tx_empty(const struct net_device *dev)
383{
384	unsigned int i;
 
 
385	for (i = 0; i < dev->num_tx_queues; i++) {
386		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
387		const struct Qdisc *q = txq->qdisc;
388
389		if (q->q.qlen)
 
390			return false;
 
391	}
 
392	return true;
393}
394
395/* Are any of the TX qdiscs changing?  */
396static inline bool qdisc_tx_changing(struct net_device *dev)
397{
398	unsigned int i;
 
399	for (i = 0; i < dev->num_tx_queues; i++) {
400		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
401		if (txq->qdisc != txq->qdisc_sleeping)
402			return true;
403	}
404	return false;
405}
406
407/* Is the device using the noop qdisc on all queues?  */
408static inline bool qdisc_tx_is_noop(const struct net_device *dev)
409{
410	unsigned int i;
 
411	for (i = 0; i < dev->num_tx_queues; i++) {
412		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
413		if (txq->qdisc != &noop_qdisc)
414			return false;
415	}
416	return true;
417}
418
419static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
420{
421	return qdisc_skb_cb(skb)->pkt_len;
422}
423
424/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
425enum net_xmit_qdisc_t {
426	__NET_XMIT_STOLEN = 0x00010000,
427	__NET_XMIT_BYPASS = 0x00020000,
428};
429
430#ifdef CONFIG_NET_CLS_ACT
431#define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
432#else
433#define net_xmit_drop_count(e)	(1)
434#endif
435
436static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
437					   const struct Qdisc *sch)
438{
439#ifdef CONFIG_NET_SCHED
440	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
441
442	if (stab)
443		__qdisc_calculate_pkt_len(skb, stab);
444#endif
445}
446
447static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 
448{
449	qdisc_calculate_pkt_len(skb, sch);
450	return sch->enqueue(skb, sch);
451}
452
453static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
454{
455	qdisc_skb_cb(skb)->pkt_len = skb->len;
456	return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
457}
458
 
 
 
 
 
 
459
460static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
461				 const struct sk_buff *skb)
462{
463	bstats->bytes += qdisc_pkt_len(skb);
464	bstats->packets += skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
465}
466
467static inline void qdisc_bstats_update(struct Qdisc *sch,
468				       const struct sk_buff *skb)
469{
470	bstats_update(&sch->bstats, skb);
471}
472
473static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
474				       struct sk_buff_head *list)
 
 
 
 
 
 
475{
476	__skb_queue_tail(list, skb);
477	sch->qstats.backlog += qdisc_pkt_len(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
478
479	return NET_XMIT_SUCCESS;
480}
481
482static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
483{
484	return __qdisc_enqueue_tail(skb, sch, &sch->q);
485}
486
487static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
488						   struct sk_buff_head *list)
489{
490	struct sk_buff *skb = __skb_dequeue(list);
491
492	if (likely(skb != NULL)) {
493		sch->qstats.backlog -= qdisc_pkt_len(skb);
494		qdisc_bstats_update(sch, skb);
 
 
 
495	}
496
497	return skb;
498}
499
500static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
501{
502	return __qdisc_dequeue_head(sch, &sch->q);
503}
504
505static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
506					      struct sk_buff_head *list)
507{
508	struct sk_buff *skb = __skb_dequeue(list);
509
510	if (likely(skb != NULL)) {
511		unsigned int len = qdisc_pkt_len(skb);
512		sch->qstats.backlog -= len;
513		kfree_skb(skb);
514		return len;
515	}
516
517	return 0;
518}
519
520static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch)
 
 
 
521{
522	return __qdisc_queue_drop_head(sch, &sch->q);
 
523}
524
525static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
526						   struct sk_buff_head *list)
 
527{
528	struct sk_buff *skb = __skb_dequeue_tail(list);
529
530	if (likely(skb != NULL))
531		sch->qstats.backlog -= qdisc_pkt_len(skb);
532
533	return skb;
 
 
 
 
 
534}
535
536static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
 
537{
538	return __qdisc_dequeue_tail(sch, &sch->q);
539}
540
541static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
542{
543	return skb_peek(&sch->q);
 
 
544}
545
546/* generic pseudo peek method for non-work-conserving qdisc */
547static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
548{
549	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
550	if (!sch->gso_skb) {
551		sch->gso_skb = sch->dequeue(sch);
552		if (sch->gso_skb)
553			/* it's still part of the queue */
 
554			sch->q.qlen++;
 
555	}
556
557	return sch->gso_skb;
558}
559
560/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
561static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
562{
563	struct sk_buff *skb = sch->gso_skb;
564
565	if (skb) {
566		sch->gso_skb = NULL;
 
567		sch->q.qlen--;
568	} else {
569		skb = sch->dequeue(sch);
570	}
571
572	return skb;
573}
574
575static inline void __qdisc_reset_queue(struct Qdisc *sch,
576				       struct sk_buff_head *list)
577{
578	/*
579	 * We do not know the backlog in bytes of this list, it
580	 * is up to the caller to correct it
581	 */
582	__skb_queue_purge(list);
 
 
 
 
 
 
 
583}
584
585static inline void qdisc_reset_queue(struct Qdisc *sch)
586{
587	__qdisc_reset_queue(sch, &sch->q);
588	sch->qstats.backlog = 0;
589}
590
591static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
592					      struct sk_buff_head *list)
593{
594	struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
595
596	if (likely(skb != NULL)) {
597		unsigned int len = qdisc_pkt_len(skb);
598		kfree_skb(skb);
599		return len;
 
 
600	}
 
601
602	return 0;
603}
604
605static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
606{
607	return __qdisc_queue_drop(sch, &sch->q);
 
608}
609
610static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
611{
612	kfree_skb(skb);
613	sch->qstats.drops++;
614
615	return NET_XMIT_DROP;
616}
617
618static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
 
619{
620	sch->qstats.drops++;
 
621
622#ifdef CONFIG_NET_CLS_ACT
623	if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
624		goto drop;
625
626	return NET_XMIT_SUCCESS;
627
628drop:
629#endif
630	kfree_skb(skb);
631	return NET_XMIT_DROP;
632}
633
634/* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
635   long it will take to send a packet given its size.
636 */
637static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
638{
639	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
640	if (slot < 0)
641		slot = 0;
642	slot >>= rtab->rate.cell_log;
643	if (slot > 255)
644		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
645	return rtab->data[slot];
646}
647
648#ifdef CONFIG_NET_CLS_ACT
649static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask,
650					    int action)
 
 
 
 
 
 
 
651{
652	struct sk_buff *n;
653
654	n = skb_clone(skb, gfp_mask);
 
655
656	if (n) {
657		n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
658		n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
659		n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
660	}
661	return n;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
662}
663#endif
664
665#endif
v4.10.11
  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