xref: /openbmc/linux/include/net/sch_generic.h (revision 4cff79e9)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __NET_SCHED_GENERIC_H
3 #define __NET_SCHED_GENERIC_H
4 
5 #include <linux/netdevice.h>
6 #include <linux/types.h>
7 #include <linux/rcupdate.h>
8 #include <linux/pkt_sched.h>
9 #include <linux/pkt_cls.h>
10 #include <linux/percpu.h>
11 #include <linux/dynamic_queue_limits.h>
12 #include <linux/list.h>
13 #include <linux/refcount.h>
14 #include <linux/workqueue.h>
15 #include <net/gen_stats.h>
16 #include <net/rtnetlink.h>
17 
18 struct Qdisc_ops;
19 struct qdisc_walker;
20 struct tcf_walker;
21 struct module;
22 
23 struct qdisc_rate_table {
24 	struct tc_ratespec rate;
25 	u32		data[256];
26 	struct qdisc_rate_table *next;
27 	int		refcnt;
28 };
29 
30 enum qdisc_state_t {
31 	__QDISC_STATE_SCHED,
32 	__QDISC_STATE_DEACTIVATED,
33 	__QDISC_STATE_RUNNING,
34 };
35 
36 struct qdisc_size_table {
37 	struct rcu_head		rcu;
38 	struct list_head	list;
39 	struct tc_sizespec	szopts;
40 	int			refcnt;
41 	u16			data[];
42 };
43 
44 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
45 struct qdisc_skb_head {
46 	struct sk_buff	*head;
47 	struct sk_buff	*tail;
48 	__u32		qlen;
49 	spinlock_t	lock;
50 };
51 
52 struct Qdisc {
53 	int 			(*enqueue)(struct sk_buff *skb,
54 					   struct Qdisc *sch,
55 					   struct sk_buff **to_free);
56 	struct sk_buff *	(*dequeue)(struct Qdisc *sch);
57 	unsigned int		flags;
58 #define TCQ_F_BUILTIN		1
59 #define TCQ_F_INGRESS		2
60 #define TCQ_F_CAN_BYPASS	4
61 #define TCQ_F_MQROOT		8
62 #define TCQ_F_ONETXQUEUE	0x10 /* dequeue_skb() can assume all skbs are for
63 				      * q->dev_queue : It can test
64 				      * netif_xmit_frozen_or_stopped() before
65 				      * dequeueing next packet.
66 				      * Its true for MQ/MQPRIO slaves, or non
67 				      * multiqueue device.
68 				      */
69 #define TCQ_F_WARN_NONWC	(1 << 16)
70 #define TCQ_F_CPUSTATS		0x20 /* run using percpu statistics */
71 #define TCQ_F_NOPARENT		0x40 /* root of its hierarchy :
72 				      * qdisc_tree_decrease_qlen() should stop.
73 				      */
74 #define TCQ_F_INVISIBLE		0x80 /* invisible by default in dump */
75 #define TCQ_F_NOLOCK		0x100 /* qdisc does not require locking */
76 #define TCQ_F_OFFLOADED		0x200 /* qdisc is offloaded to HW */
77 	u32			limit;
78 	const struct Qdisc_ops	*ops;
79 	struct qdisc_size_table	__rcu *stab;
80 	struct hlist_node       hash;
81 	u32			handle;
82 	u32			parent;
83 
84 	struct netdev_queue	*dev_queue;
85 
86 	struct net_rate_estimator __rcu *rate_est;
87 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
88 	struct gnet_stats_queue	__percpu *cpu_qstats;
89 
90 	/*
91 	 * For performance sake on SMP, we put highly modified fields at the end
92 	 */
93 	struct sk_buff_head	gso_skb ____cacheline_aligned_in_smp;
94 	struct qdisc_skb_head	q;
95 	struct gnet_stats_basic_packed bstats;
96 	seqcount_t		running;
97 	struct gnet_stats_queue	qstats;
98 	unsigned long		state;
99 	struct Qdisc            *next_sched;
100 	struct sk_buff_head	skb_bad_txq;
101 	int			padded;
102 	refcount_t		refcnt;
103 
104 	spinlock_t		busylock ____cacheline_aligned_in_smp;
105 };
106 
107 static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
108 {
109 	if (qdisc->flags & TCQ_F_BUILTIN)
110 		return;
111 	refcount_inc(&qdisc->refcnt);
112 }
113 
114 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
115 {
116 	return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
117 }
118 
119 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
120 {
121 	if (qdisc_is_running(qdisc))
122 		return false;
123 	/* Variant of write_seqcount_begin() telling lockdep a trylock
124 	 * was attempted.
125 	 */
126 	raw_write_seqcount_begin(&qdisc->running);
127 	seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
128 	return true;
129 }
130 
131 static inline void qdisc_run_end(struct Qdisc *qdisc)
132 {
133 	write_seqcount_end(&qdisc->running);
134 }
135 
136 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
137 {
138 	return qdisc->flags & TCQ_F_ONETXQUEUE;
139 }
140 
141 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
142 {
143 #ifdef CONFIG_BQL
144 	/* Non-BQL migrated drivers will return 0, too. */
145 	return dql_avail(&txq->dql);
146 #else
147 	return 0;
148 #endif
149 }
150 
151 struct Qdisc_class_ops {
152 	/* Child qdisc manipulation */
153 	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
154 	int			(*graft)(struct Qdisc *, unsigned long cl,
155 					struct Qdisc *, struct Qdisc **,
156 					struct netlink_ext_ack *extack);
157 	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
158 	void			(*qlen_notify)(struct Qdisc *, unsigned long);
159 
160 	/* Class manipulation routines */
161 	unsigned long		(*find)(struct Qdisc *, u32 classid);
162 	int			(*change)(struct Qdisc *, u32, u32,
163 					struct nlattr **, unsigned long *,
164 					struct netlink_ext_ack *);
165 	int			(*delete)(struct Qdisc *, unsigned long);
166 	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
167 
168 	/* Filter manipulation */
169 	struct tcf_block *	(*tcf_block)(struct Qdisc *sch,
170 					     unsigned long arg,
171 					     struct netlink_ext_ack *extack);
172 	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
173 					u32 classid);
174 	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
175 
176 	/* rtnetlink specific */
177 	int			(*dump)(struct Qdisc *, unsigned long,
178 					struct sk_buff *skb, struct tcmsg*);
179 	int			(*dump_stats)(struct Qdisc *, unsigned long,
180 					struct gnet_dump *);
181 };
182 
183 struct Qdisc_ops {
184 	struct Qdisc_ops	*next;
185 	const struct Qdisc_class_ops	*cl_ops;
186 	char			id[IFNAMSIZ];
187 	int			priv_size;
188 	unsigned int		static_flags;
189 
190 	int 			(*enqueue)(struct sk_buff *skb,
191 					   struct Qdisc *sch,
192 					   struct sk_buff **to_free);
193 	struct sk_buff *	(*dequeue)(struct Qdisc *);
194 	struct sk_buff *	(*peek)(struct Qdisc *);
195 
196 	int			(*init)(struct Qdisc *sch, struct nlattr *arg,
197 					struct netlink_ext_ack *extack);
198 	void			(*reset)(struct Qdisc *);
199 	void			(*destroy)(struct Qdisc *);
200 	int			(*change)(struct Qdisc *sch,
201 					  struct nlattr *arg,
202 					  struct netlink_ext_ack *extack);
203 	void			(*attach)(struct Qdisc *sch);
204 	int			(*change_tx_queue_len)(struct Qdisc *, unsigned int);
205 
206 	int			(*dump)(struct Qdisc *, struct sk_buff *);
207 	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
208 
209 	void			(*ingress_block_set)(struct Qdisc *sch,
210 						     u32 block_index);
211 	void			(*egress_block_set)(struct Qdisc *sch,
212 						    u32 block_index);
213 	u32			(*ingress_block_get)(struct Qdisc *sch);
214 	u32			(*egress_block_get)(struct Qdisc *sch);
215 
216 	struct module		*owner;
217 };
218 
219 
220 struct tcf_result {
221 	union {
222 		struct {
223 			unsigned long	class;
224 			u32		classid;
225 		};
226 		const struct tcf_proto *goto_tp;
227 	};
228 };
229 
230 struct tcf_proto_ops {
231 	struct list_head	head;
232 	char			kind[IFNAMSIZ];
233 
234 	int			(*classify)(struct sk_buff *,
235 					    const struct tcf_proto *,
236 					    struct tcf_result *);
237 	int			(*init)(struct tcf_proto*);
238 	void			(*destroy)(struct tcf_proto *tp,
239 					   struct netlink_ext_ack *extack);
240 
241 	void*			(*get)(struct tcf_proto*, u32 handle);
242 	int			(*change)(struct net *net, struct sk_buff *,
243 					struct tcf_proto*, unsigned long,
244 					u32 handle, struct nlattr **,
245 					void **, bool,
246 					struct netlink_ext_ack *);
247 	int			(*delete)(struct tcf_proto *tp, void *arg,
248 					  bool *last,
249 					  struct netlink_ext_ack *);
250 	void			(*walk)(struct tcf_proto*, struct tcf_walker *arg);
251 	void			(*bind_class)(void *, u32, unsigned long);
252 
253 	/* rtnetlink specific */
254 	int			(*dump)(struct net*, struct tcf_proto*, void *,
255 					struct sk_buff *skb, struct tcmsg*);
256 
257 	struct module		*owner;
258 };
259 
260 struct tcf_proto {
261 	/* Fast access part */
262 	struct tcf_proto __rcu	*next;
263 	void __rcu		*root;
264 	int			(*classify)(struct sk_buff *,
265 					    const struct tcf_proto *,
266 					    struct tcf_result *);
267 	__be16			protocol;
268 
269 	/* All the rest */
270 	u32			prio;
271 	void			*data;
272 	const struct tcf_proto_ops	*ops;
273 	struct tcf_chain	*chain;
274 	struct rcu_head		rcu;
275 };
276 
277 struct qdisc_skb_cb {
278 	unsigned int		pkt_len;
279 	u16			slave_dev_queue_mapping;
280 	u16			tc_classid;
281 #define QDISC_CB_PRIV_LEN 20
282 	unsigned char		data[QDISC_CB_PRIV_LEN];
283 };
284 
285 typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);
286 
287 struct tcf_chain {
288 	struct tcf_proto __rcu *filter_chain;
289 	struct list_head filter_chain_list;
290 	struct list_head list;
291 	struct tcf_block *block;
292 	u32 index; /* chain index */
293 	unsigned int refcnt;
294 };
295 
296 struct tcf_block {
297 	struct list_head chain_list;
298 	u32 index; /* block index for shared blocks */
299 	unsigned int refcnt;
300 	struct net *net;
301 	struct Qdisc *q;
302 	struct list_head cb_list;
303 	struct list_head owner_list;
304 	bool keep_dst;
305 	unsigned int offloadcnt; /* Number of oddloaded filters */
306 	unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
307 };
308 
309 static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
310 {
311 	if (*flags & TCA_CLS_FLAGS_IN_HW)
312 		return;
313 	*flags |= TCA_CLS_FLAGS_IN_HW;
314 	block->offloadcnt++;
315 }
316 
317 static inline void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
318 {
319 	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
320 		return;
321 	*flags &= ~TCA_CLS_FLAGS_IN_HW;
322 	block->offloadcnt--;
323 }
324 
325 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
326 {
327 	struct qdisc_skb_cb *qcb;
328 
329 	BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
330 	BUILD_BUG_ON(sizeof(qcb->data) < sz);
331 }
332 
333 static inline int qdisc_qlen_cpu(const struct Qdisc *q)
334 {
335 	return this_cpu_ptr(q->cpu_qstats)->qlen;
336 }
337 
338 static inline int qdisc_qlen(const struct Qdisc *q)
339 {
340 	return q->q.qlen;
341 }
342 
343 static inline int qdisc_qlen_sum(const struct Qdisc *q)
344 {
345 	__u32 qlen = 0;
346 	int i;
347 
348 	if (q->flags & TCQ_F_NOLOCK) {
349 		for_each_possible_cpu(i)
350 			qlen += per_cpu_ptr(q->cpu_qstats, i)->qlen;
351 	} else {
352 		qlen = q->q.qlen;
353 	}
354 
355 	return qlen;
356 }
357 
358 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
359 {
360 	return (struct qdisc_skb_cb *)skb->cb;
361 }
362 
363 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
364 {
365 	return &qdisc->q.lock;
366 }
367 
368 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
369 {
370 	struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
371 
372 	return q;
373 }
374 
375 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
376 {
377 	return qdisc->dev_queue->qdisc_sleeping;
378 }
379 
380 /* The qdisc root lock is a mechanism by which to top level
381  * of a qdisc tree can be locked from any qdisc node in the
382  * forest.  This allows changing the configuration of some
383  * aspect of the qdisc tree while blocking out asynchronous
384  * qdisc access in the packet processing paths.
385  *
386  * It is only legal to do this when the root will not change
387  * on us.  Otherwise we'll potentially lock the wrong qdisc
388  * root.  This is enforced by holding the RTNL semaphore, which
389  * all users of this lock accessor must do.
390  */
391 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
392 {
393 	struct Qdisc *root = qdisc_root(qdisc);
394 
395 	ASSERT_RTNL();
396 	return qdisc_lock(root);
397 }
398 
399 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
400 {
401 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
402 
403 	ASSERT_RTNL();
404 	return qdisc_lock(root);
405 }
406 
407 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
408 {
409 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
410 
411 	ASSERT_RTNL();
412 	return &root->running;
413 }
414 
415 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
416 {
417 	return qdisc->dev_queue->dev;
418 }
419 
420 static inline void sch_tree_lock(const struct Qdisc *q)
421 {
422 	spin_lock_bh(qdisc_root_sleeping_lock(q));
423 }
424 
425 static inline void sch_tree_unlock(const struct Qdisc *q)
426 {
427 	spin_unlock_bh(qdisc_root_sleeping_lock(q));
428 }
429 
430 extern struct Qdisc noop_qdisc;
431 extern struct Qdisc_ops noop_qdisc_ops;
432 extern struct Qdisc_ops pfifo_fast_ops;
433 extern struct Qdisc_ops mq_qdisc_ops;
434 extern struct Qdisc_ops noqueue_qdisc_ops;
435 extern const struct Qdisc_ops *default_qdisc_ops;
436 static inline const struct Qdisc_ops *
437 get_default_qdisc_ops(const struct net_device *dev, int ntx)
438 {
439 	return ntx < dev->real_num_tx_queues ?
440 			default_qdisc_ops : &pfifo_fast_ops;
441 }
442 
443 struct Qdisc_class_common {
444 	u32			classid;
445 	struct hlist_node	hnode;
446 };
447 
448 struct Qdisc_class_hash {
449 	struct hlist_head	*hash;
450 	unsigned int		hashsize;
451 	unsigned int		hashmask;
452 	unsigned int		hashelems;
453 };
454 
455 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
456 {
457 	id ^= id >> 8;
458 	id ^= id >> 4;
459 	return id & mask;
460 }
461 
462 static inline struct Qdisc_class_common *
463 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
464 {
465 	struct Qdisc_class_common *cl;
466 	unsigned int h;
467 
468 	if (!id)
469 		return NULL;
470 
471 	h = qdisc_class_hash(id, hash->hashmask);
472 	hlist_for_each_entry(cl, &hash->hash[h], hnode) {
473 		if (cl->classid == id)
474 			return cl;
475 	}
476 	return NULL;
477 }
478 
479 static inline int tc_classid_to_hwtc(struct net_device *dev, u32 classid)
480 {
481 	u32 hwtc = TC_H_MIN(classid) - TC_H_MIN_PRIORITY;
482 
483 	return (hwtc < netdev_get_num_tc(dev)) ? hwtc : -EINVAL;
484 }
485 
486 int qdisc_class_hash_init(struct Qdisc_class_hash *);
487 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
488 			     struct Qdisc_class_common *);
489 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
490 			     struct Qdisc_class_common *);
491 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
492 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
493 
494 int dev_qdisc_change_tx_queue_len(struct net_device *dev);
495 void dev_init_scheduler(struct net_device *dev);
496 void dev_shutdown(struct net_device *dev);
497 void dev_activate(struct net_device *dev);
498 void dev_deactivate(struct net_device *dev);
499 void dev_deactivate_many(struct list_head *head);
500 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
501 			      struct Qdisc *qdisc);
502 void qdisc_reset(struct Qdisc *qdisc);
503 void qdisc_destroy(struct Qdisc *qdisc);
504 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
505 			       unsigned int len);
506 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
507 			  const struct Qdisc_ops *ops,
508 			  struct netlink_ext_ack *extack);
509 void qdisc_free(struct Qdisc *qdisc);
510 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
511 				const struct Qdisc_ops *ops, u32 parentid,
512 				struct netlink_ext_ack *extack);
513 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
514 			       const struct qdisc_size_table *stab);
515 int skb_do_redirect(struct sk_buff *);
516 
517 static inline void skb_reset_tc(struct sk_buff *skb)
518 {
519 #ifdef CONFIG_NET_CLS_ACT
520 	skb->tc_redirected = 0;
521 #endif
522 }
523 
524 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
525 {
526 #ifdef CONFIG_NET_CLS_ACT
527 	return skb->tc_at_ingress;
528 #else
529 	return false;
530 #endif
531 }
532 
533 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
534 {
535 #ifdef CONFIG_NET_CLS_ACT
536 	if (skb->tc_skip_classify) {
537 		skb->tc_skip_classify = 0;
538 		return true;
539 	}
540 #endif
541 	return false;
542 }
543 
544 /* Reset all TX qdiscs greater than index of a device.  */
545 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
546 {
547 	struct Qdisc *qdisc;
548 
549 	for (; i < dev->num_tx_queues; i++) {
550 		qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
551 		if (qdisc) {
552 			spin_lock_bh(qdisc_lock(qdisc));
553 			qdisc_reset(qdisc);
554 			spin_unlock_bh(qdisc_lock(qdisc));
555 		}
556 	}
557 }
558 
559 static inline void qdisc_reset_all_tx(struct net_device *dev)
560 {
561 	qdisc_reset_all_tx_gt(dev, 0);
562 }
563 
564 /* Are all TX queues of the device empty?  */
565 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
566 {
567 	unsigned int i;
568 
569 	rcu_read_lock();
570 	for (i = 0; i < dev->num_tx_queues; i++) {
571 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
572 		const struct Qdisc *q = rcu_dereference(txq->qdisc);
573 
574 		if (q->q.qlen) {
575 			rcu_read_unlock();
576 			return false;
577 		}
578 	}
579 	rcu_read_unlock();
580 	return true;
581 }
582 
583 /* Are any of the TX qdiscs changing?  */
584 static inline bool qdisc_tx_changing(const struct net_device *dev)
585 {
586 	unsigned int i;
587 
588 	for (i = 0; i < dev->num_tx_queues; i++) {
589 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
590 		if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
591 			return true;
592 	}
593 	return false;
594 }
595 
596 /* Is the device using the noop qdisc on all queues?  */
597 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
598 {
599 	unsigned int i;
600 
601 	for (i = 0; i < dev->num_tx_queues; i++) {
602 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
603 		if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
604 			return false;
605 	}
606 	return true;
607 }
608 
609 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
610 {
611 	return qdisc_skb_cb(skb)->pkt_len;
612 }
613 
614 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
615 enum net_xmit_qdisc_t {
616 	__NET_XMIT_STOLEN = 0x00010000,
617 	__NET_XMIT_BYPASS = 0x00020000,
618 };
619 
620 #ifdef CONFIG_NET_CLS_ACT
621 #define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
622 #else
623 #define net_xmit_drop_count(e)	(1)
624 #endif
625 
626 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
627 					   const struct Qdisc *sch)
628 {
629 #ifdef CONFIG_NET_SCHED
630 	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
631 
632 	if (stab)
633 		__qdisc_calculate_pkt_len(skb, stab);
634 #endif
635 }
636 
637 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
638 				struct sk_buff **to_free)
639 {
640 	qdisc_calculate_pkt_len(skb, sch);
641 	return sch->enqueue(skb, sch, to_free);
642 }
643 
644 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
645 {
646 	return q->flags & TCQ_F_CPUSTATS;
647 }
648 
649 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
650 				  __u64 bytes, __u32 packets)
651 {
652 	bstats->bytes += bytes;
653 	bstats->packets += packets;
654 }
655 
656 static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
657 				 const struct sk_buff *skb)
658 {
659 	_bstats_update(bstats,
660 		       qdisc_pkt_len(skb),
661 		       skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
662 }
663 
664 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
665 				      __u64 bytes, __u32 packets)
666 {
667 	u64_stats_update_begin(&bstats->syncp);
668 	_bstats_update(&bstats->bstats, bytes, packets);
669 	u64_stats_update_end(&bstats->syncp);
670 }
671 
672 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
673 				     const struct sk_buff *skb)
674 {
675 	u64_stats_update_begin(&bstats->syncp);
676 	bstats_update(&bstats->bstats, skb);
677 	u64_stats_update_end(&bstats->syncp);
678 }
679 
680 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
681 					   const struct sk_buff *skb)
682 {
683 	bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
684 }
685 
686 static inline void qdisc_bstats_update(struct Qdisc *sch,
687 				       const struct sk_buff *skb)
688 {
689 	bstats_update(&sch->bstats, skb);
690 }
691 
692 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
693 					    const struct sk_buff *skb)
694 {
695 	sch->qstats.backlog -= qdisc_pkt_len(skb);
696 }
697 
698 static inline void qdisc_qstats_cpu_backlog_dec(struct Qdisc *sch,
699 						const struct sk_buff *skb)
700 {
701 	this_cpu_sub(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
702 }
703 
704 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
705 					    const struct sk_buff *skb)
706 {
707 	sch->qstats.backlog += qdisc_pkt_len(skb);
708 }
709 
710 static inline void qdisc_qstats_cpu_backlog_inc(struct Qdisc *sch,
711 						const struct sk_buff *skb)
712 {
713 	this_cpu_add(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
714 }
715 
716 static inline void qdisc_qstats_cpu_qlen_inc(struct Qdisc *sch)
717 {
718 	this_cpu_inc(sch->cpu_qstats->qlen);
719 }
720 
721 static inline void qdisc_qstats_cpu_qlen_dec(struct Qdisc *sch)
722 {
723 	this_cpu_dec(sch->cpu_qstats->qlen);
724 }
725 
726 static inline void qdisc_qstats_cpu_requeues_inc(struct Qdisc *sch)
727 {
728 	this_cpu_inc(sch->cpu_qstats->requeues);
729 }
730 
731 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
732 {
733 	sch->qstats.drops += count;
734 }
735 
736 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
737 {
738 	qstats->drops++;
739 }
740 
741 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
742 {
743 	qstats->overlimits++;
744 }
745 
746 static inline void qdisc_qstats_drop(struct Qdisc *sch)
747 {
748 	qstats_drop_inc(&sch->qstats);
749 }
750 
751 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
752 {
753 	this_cpu_inc(sch->cpu_qstats->drops);
754 }
755 
756 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
757 {
758 	sch->qstats.overlimits++;
759 }
760 
761 static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
762 {
763 	qh->head = NULL;
764 	qh->tail = NULL;
765 	qh->qlen = 0;
766 }
767 
768 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
769 				       struct qdisc_skb_head *qh)
770 {
771 	struct sk_buff *last = qh->tail;
772 
773 	if (last) {
774 		skb->next = NULL;
775 		last->next = skb;
776 		qh->tail = skb;
777 	} else {
778 		qh->tail = skb;
779 		qh->head = skb;
780 	}
781 	qh->qlen++;
782 	qdisc_qstats_backlog_inc(sch, skb);
783 
784 	return NET_XMIT_SUCCESS;
785 }
786 
787 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
788 {
789 	return __qdisc_enqueue_tail(skb, sch, &sch->q);
790 }
791 
792 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
793 {
794 	struct sk_buff *skb = qh->head;
795 
796 	if (likely(skb != NULL)) {
797 		qh->head = skb->next;
798 		qh->qlen--;
799 		if (qh->head == NULL)
800 			qh->tail = NULL;
801 		skb->next = NULL;
802 	}
803 
804 	return skb;
805 }
806 
807 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
808 {
809 	struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
810 
811 	if (likely(skb != NULL)) {
812 		qdisc_qstats_backlog_dec(sch, skb);
813 		qdisc_bstats_update(sch, skb);
814 	}
815 
816 	return skb;
817 }
818 
819 /* Instead of calling kfree_skb() while root qdisc lock is held,
820  * queue the skb for future freeing at end of __dev_xmit_skb()
821  */
822 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
823 {
824 	skb->next = *to_free;
825 	*to_free = skb;
826 }
827 
828 static inline void __qdisc_drop_all(struct sk_buff *skb,
829 				    struct sk_buff **to_free)
830 {
831 	if (skb->prev)
832 		skb->prev->next = *to_free;
833 	else
834 		skb->next = *to_free;
835 	*to_free = skb;
836 }
837 
838 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
839 						   struct qdisc_skb_head *qh,
840 						   struct sk_buff **to_free)
841 {
842 	struct sk_buff *skb = __qdisc_dequeue_head(qh);
843 
844 	if (likely(skb != NULL)) {
845 		unsigned int len = qdisc_pkt_len(skb);
846 
847 		qdisc_qstats_backlog_dec(sch, skb);
848 		__qdisc_drop(skb, to_free);
849 		return len;
850 	}
851 
852 	return 0;
853 }
854 
855 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
856 						 struct sk_buff **to_free)
857 {
858 	return __qdisc_queue_drop_head(sch, &sch->q, to_free);
859 }
860 
861 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
862 {
863 	const struct qdisc_skb_head *qh = &sch->q;
864 
865 	return qh->head;
866 }
867 
868 /* generic pseudo peek method for non-work-conserving qdisc */
869 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
870 {
871 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
872 
873 	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
874 	if (!skb) {
875 		skb = sch->dequeue(sch);
876 
877 		if (skb) {
878 			__skb_queue_head(&sch->gso_skb, skb);
879 			/* it's still part of the queue */
880 			qdisc_qstats_backlog_inc(sch, skb);
881 			sch->q.qlen++;
882 		}
883 	}
884 
885 	return skb;
886 }
887 
888 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
889 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
890 {
891 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
892 
893 	if (skb) {
894 		skb = __skb_dequeue(&sch->gso_skb);
895 		qdisc_qstats_backlog_dec(sch, skb);
896 		sch->q.qlen--;
897 	} else {
898 		skb = sch->dequeue(sch);
899 	}
900 
901 	return skb;
902 }
903 
904 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
905 {
906 	/*
907 	 * We do not know the backlog in bytes of this list, it
908 	 * is up to the caller to correct it
909 	 */
910 	ASSERT_RTNL();
911 	if (qh->qlen) {
912 		rtnl_kfree_skbs(qh->head, qh->tail);
913 
914 		qh->head = NULL;
915 		qh->tail = NULL;
916 		qh->qlen = 0;
917 	}
918 }
919 
920 static inline void qdisc_reset_queue(struct Qdisc *sch)
921 {
922 	__qdisc_reset_queue(&sch->q);
923 	sch->qstats.backlog = 0;
924 }
925 
926 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
927 					  struct Qdisc **pold)
928 {
929 	struct Qdisc *old;
930 
931 	sch_tree_lock(sch);
932 	old = *pold;
933 	*pold = new;
934 	if (old != NULL) {
935 		unsigned int qlen = old->q.qlen;
936 		unsigned int backlog = old->qstats.backlog;
937 
938 		qdisc_reset(old);
939 		qdisc_tree_reduce_backlog(old, qlen, backlog);
940 	}
941 	sch_tree_unlock(sch);
942 
943 	return old;
944 }
945 
946 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
947 {
948 	rtnl_kfree_skbs(skb, skb);
949 	qdisc_qstats_drop(sch);
950 }
951 
952 static inline int qdisc_drop_cpu(struct sk_buff *skb, struct Qdisc *sch,
953 				 struct sk_buff **to_free)
954 {
955 	__qdisc_drop(skb, to_free);
956 	qdisc_qstats_cpu_drop(sch);
957 
958 	return NET_XMIT_DROP;
959 }
960 
961 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
962 			     struct sk_buff **to_free)
963 {
964 	__qdisc_drop(skb, to_free);
965 	qdisc_qstats_drop(sch);
966 
967 	return NET_XMIT_DROP;
968 }
969 
970 static inline int qdisc_drop_all(struct sk_buff *skb, struct Qdisc *sch,
971 				 struct sk_buff **to_free)
972 {
973 	__qdisc_drop_all(skb, to_free);
974 	qdisc_qstats_drop(sch);
975 
976 	return NET_XMIT_DROP;
977 }
978 
979 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
980    long it will take to send a packet given its size.
981  */
982 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
983 {
984 	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
985 	if (slot < 0)
986 		slot = 0;
987 	slot >>= rtab->rate.cell_log;
988 	if (slot > 255)
989 		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
990 	return rtab->data[slot];
991 }
992 
993 struct psched_ratecfg {
994 	u64	rate_bytes_ps; /* bytes per second */
995 	u32	mult;
996 	u16	overhead;
997 	u8	linklayer;
998 	u8	shift;
999 };
1000 
1001 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
1002 				unsigned int len)
1003 {
1004 	len += r->overhead;
1005 
1006 	if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
1007 		return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
1008 
1009 	return ((u64)len * r->mult) >> r->shift;
1010 }
1011 
1012 void psched_ratecfg_precompute(struct psched_ratecfg *r,
1013 			       const struct tc_ratespec *conf,
1014 			       u64 rate64);
1015 
1016 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
1017 					  const struct psched_ratecfg *r)
1018 {
1019 	memset(res, 0, sizeof(*res));
1020 
1021 	/* legacy struct tc_ratespec has a 32bit @rate field
1022 	 * Qdisc using 64bit rate should add new attributes
1023 	 * in order to maintain compatibility.
1024 	 */
1025 	res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
1026 
1027 	res->overhead = r->overhead;
1028 	res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
1029 }
1030 
1031 /* Mini Qdisc serves for specific needs of ingress/clsact Qdisc.
1032  * The fast path only needs to access filter list and to update stats
1033  */
1034 struct mini_Qdisc {
1035 	struct tcf_proto *filter_list;
1036 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
1037 	struct gnet_stats_queue	__percpu *cpu_qstats;
1038 	struct rcu_head rcu;
1039 };
1040 
1041 static inline void mini_qdisc_bstats_cpu_update(struct mini_Qdisc *miniq,
1042 						const struct sk_buff *skb)
1043 {
1044 	bstats_cpu_update(this_cpu_ptr(miniq->cpu_bstats), skb);
1045 }
1046 
1047 static inline void mini_qdisc_qstats_cpu_drop(struct mini_Qdisc *miniq)
1048 {
1049 	this_cpu_inc(miniq->cpu_qstats->drops);
1050 }
1051 
1052 struct mini_Qdisc_pair {
1053 	struct mini_Qdisc miniq1;
1054 	struct mini_Qdisc miniq2;
1055 	struct mini_Qdisc __rcu **p_miniq;
1056 };
1057 
1058 void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
1059 			  struct tcf_proto *tp_head);
1060 void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
1061 			  struct mini_Qdisc __rcu **p_miniq);
1062 
1063 #endif
1064