xref: /openbmc/linux/include/net/sch_generic.h (revision 12382d11)
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 <linux/mutex.h>
16 #include <linux/rwsem.h>
17 #include <linux/atomic.h>
18 #include <linux/hashtable.h>
19 #include <net/gen_stats.h>
20 #include <net/rtnetlink.h>
21 #include <net/flow_offload.h>
22 
23 struct Qdisc_ops;
24 struct qdisc_walker;
25 struct tcf_walker;
26 struct module;
27 struct bpf_flow_keys;
28 
29 struct qdisc_rate_table {
30 	struct tc_ratespec rate;
31 	u32		data[256];
32 	struct qdisc_rate_table *next;
33 	int		refcnt;
34 };
35 
36 enum qdisc_state_t {
37 	__QDISC_STATE_SCHED,
38 	__QDISC_STATE_DEACTIVATED,
39 	__QDISC_STATE_MISSED,
40 	__QDISC_STATE_DRAINING,
41 };
42 
43 enum qdisc_state2_t {
44 	/* Only for !TCQ_F_NOLOCK qdisc. Never access it directly.
45 	 * Use qdisc_run_begin/end() or qdisc_is_running() instead.
46 	 */
47 	__QDISC_STATE2_RUNNING,
48 };
49 
50 #define QDISC_STATE_MISSED	BIT(__QDISC_STATE_MISSED)
51 #define QDISC_STATE_DRAINING	BIT(__QDISC_STATE_DRAINING)
52 
53 #define QDISC_STATE_NON_EMPTY	(QDISC_STATE_MISSED | \
54 					QDISC_STATE_DRAINING)
55 
56 struct qdisc_size_table {
57 	struct rcu_head		rcu;
58 	struct list_head	list;
59 	struct tc_sizespec	szopts;
60 	int			refcnt;
61 	u16			data[];
62 };
63 
64 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
65 struct qdisc_skb_head {
66 	struct sk_buff	*head;
67 	struct sk_buff	*tail;
68 	__u32		qlen;
69 	spinlock_t	lock;
70 };
71 
72 struct Qdisc {
73 	int 			(*enqueue)(struct sk_buff *skb,
74 					   struct Qdisc *sch,
75 					   struct sk_buff **to_free);
76 	struct sk_buff *	(*dequeue)(struct Qdisc *sch);
77 	unsigned int		flags;
78 #define TCQ_F_BUILTIN		1
79 #define TCQ_F_INGRESS		2
80 #define TCQ_F_CAN_BYPASS	4
81 #define TCQ_F_MQROOT		8
82 #define TCQ_F_ONETXQUEUE	0x10 /* dequeue_skb() can assume all skbs are for
83 				      * q->dev_queue : It can test
84 				      * netif_xmit_frozen_or_stopped() before
85 				      * dequeueing next packet.
86 				      * Its true for MQ/MQPRIO slaves, or non
87 				      * multiqueue device.
88 				      */
89 #define TCQ_F_WARN_NONWC	(1 << 16)
90 #define TCQ_F_CPUSTATS		0x20 /* run using percpu statistics */
91 #define TCQ_F_NOPARENT		0x40 /* root of its hierarchy :
92 				      * qdisc_tree_decrease_qlen() should stop.
93 				      */
94 #define TCQ_F_INVISIBLE		0x80 /* invisible by default in dump */
95 #define TCQ_F_NOLOCK		0x100 /* qdisc does not require locking */
96 #define TCQ_F_OFFLOADED		0x200 /* qdisc is offloaded to HW */
97 	u32			limit;
98 	const struct Qdisc_ops	*ops;
99 	struct qdisc_size_table	__rcu *stab;
100 	struct hlist_node       hash;
101 	u32			handle;
102 	u32			parent;
103 
104 	struct netdev_queue	*dev_queue;
105 
106 	struct net_rate_estimator __rcu *rate_est;
107 	struct gnet_stats_basic_sync __percpu *cpu_bstats;
108 	struct gnet_stats_queue	__percpu *cpu_qstats;
109 	int			pad;
110 	refcount_t		refcnt;
111 
112 	/*
113 	 * For performance sake on SMP, we put highly modified fields at the end
114 	 */
115 	struct sk_buff_head	gso_skb ____cacheline_aligned_in_smp;
116 	struct qdisc_skb_head	q;
117 	struct gnet_stats_basic_sync bstats;
118 	struct gnet_stats_queue	qstats;
119 	unsigned long		state;
120 	unsigned long		state2; /* must be written under qdisc spinlock */
121 	struct Qdisc            *next_sched;
122 	struct sk_buff_head	skb_bad_txq;
123 
124 	spinlock_t		busylock ____cacheline_aligned_in_smp;
125 	spinlock_t		seqlock;
126 
127 	struct rcu_head		rcu;
128 	netdevice_tracker	dev_tracker;
129 	/* private data */
130 	long privdata[] ____cacheline_aligned;
131 };
132 
133 static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
134 {
135 	if (qdisc->flags & TCQ_F_BUILTIN)
136 		return;
137 	refcount_inc(&qdisc->refcnt);
138 }
139 
140 /* Intended to be used by unlocked users, when concurrent qdisc release is
141  * possible.
142  */
143 
144 static inline struct Qdisc *qdisc_refcount_inc_nz(struct Qdisc *qdisc)
145 {
146 	if (qdisc->flags & TCQ_F_BUILTIN)
147 		return qdisc;
148 	if (refcount_inc_not_zero(&qdisc->refcnt))
149 		return qdisc;
150 	return NULL;
151 }
152 
153 /* For !TCQ_F_NOLOCK qdisc: callers must either call this within a qdisc
154  * root_lock section, or provide their own memory barriers -- ordering
155  * against qdisc_run_begin/end() atomic bit operations.
156  */
157 static inline bool qdisc_is_running(struct Qdisc *qdisc)
158 {
159 	if (qdisc->flags & TCQ_F_NOLOCK)
160 		return spin_is_locked(&qdisc->seqlock);
161 	return test_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
162 }
163 
164 static inline bool nolock_qdisc_is_empty(const struct Qdisc *qdisc)
165 {
166 	return !(READ_ONCE(qdisc->state) & QDISC_STATE_NON_EMPTY);
167 }
168 
169 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
170 {
171 	return q->flags & TCQ_F_CPUSTATS;
172 }
173 
174 static inline bool qdisc_is_empty(const struct Qdisc *qdisc)
175 {
176 	if (qdisc_is_percpu_stats(qdisc))
177 		return nolock_qdisc_is_empty(qdisc);
178 	return !READ_ONCE(qdisc->q.qlen);
179 }
180 
181 /* For !TCQ_F_NOLOCK qdisc, qdisc_run_begin/end() must be invoked with
182  * the qdisc root lock acquired.
183  */
184 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
185 {
186 	if (qdisc->flags & TCQ_F_NOLOCK) {
187 		if (spin_trylock(&qdisc->seqlock))
188 			return true;
189 
190 		/* No need to insist if the MISSED flag was already set.
191 		 * Note that test_and_set_bit() also gives us memory ordering
192 		 * guarantees wrt potential earlier enqueue() and below
193 		 * spin_trylock(), both of which are necessary to prevent races
194 		 */
195 		if (test_and_set_bit(__QDISC_STATE_MISSED, &qdisc->state))
196 			return false;
197 
198 		/* Try to take the lock again to make sure that we will either
199 		 * grab it or the CPU that still has it will see MISSED set
200 		 * when testing it in qdisc_run_end()
201 		 */
202 		return spin_trylock(&qdisc->seqlock);
203 	}
204 	return !__test_and_set_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
205 }
206 
207 static inline void qdisc_run_end(struct Qdisc *qdisc)
208 {
209 	if (qdisc->flags & TCQ_F_NOLOCK) {
210 		spin_unlock(&qdisc->seqlock);
211 
212 		/* spin_unlock() only has store-release semantic. The unlock
213 		 * and test_bit() ordering is a store-load ordering, so a full
214 		 * memory barrier is needed here.
215 		 */
216 		smp_mb();
217 
218 		if (unlikely(test_bit(__QDISC_STATE_MISSED,
219 				      &qdisc->state)))
220 			__netif_schedule(qdisc);
221 	} else {
222 		__clear_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
223 	}
224 }
225 
226 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
227 {
228 	return qdisc->flags & TCQ_F_ONETXQUEUE;
229 }
230 
231 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
232 {
233 #ifdef CONFIG_BQL
234 	/* Non-BQL migrated drivers will return 0, too. */
235 	return dql_avail(&txq->dql);
236 #else
237 	return 0;
238 #endif
239 }
240 
241 struct Qdisc_class_ops {
242 	unsigned int		flags;
243 	/* Child qdisc manipulation */
244 	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
245 	int			(*graft)(struct Qdisc *, unsigned long cl,
246 					struct Qdisc *, struct Qdisc **,
247 					struct netlink_ext_ack *extack);
248 	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
249 	void			(*qlen_notify)(struct Qdisc *, unsigned long);
250 
251 	/* Class manipulation routines */
252 	unsigned long		(*find)(struct Qdisc *, u32 classid);
253 	int			(*change)(struct Qdisc *, u32, u32,
254 					struct nlattr **, unsigned long *,
255 					struct netlink_ext_ack *);
256 	int			(*delete)(struct Qdisc *, unsigned long,
257 					  struct netlink_ext_ack *);
258 	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
259 
260 	/* Filter manipulation */
261 	struct tcf_block *	(*tcf_block)(struct Qdisc *sch,
262 					     unsigned long arg,
263 					     struct netlink_ext_ack *extack);
264 	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
265 					u32 classid);
266 	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
267 
268 	/* rtnetlink specific */
269 	int			(*dump)(struct Qdisc *, unsigned long,
270 					struct sk_buff *skb, struct tcmsg*);
271 	int			(*dump_stats)(struct Qdisc *, unsigned long,
272 					struct gnet_dump *);
273 };
274 
275 /* Qdisc_class_ops flag values */
276 
277 /* Implements API that doesn't require rtnl lock */
278 enum qdisc_class_ops_flags {
279 	QDISC_CLASS_OPS_DOIT_UNLOCKED = 1,
280 };
281 
282 struct Qdisc_ops {
283 	struct Qdisc_ops	*next;
284 	const struct Qdisc_class_ops	*cl_ops;
285 	char			id[IFNAMSIZ];
286 	int			priv_size;
287 	unsigned int		static_flags;
288 
289 	int 			(*enqueue)(struct sk_buff *skb,
290 					   struct Qdisc *sch,
291 					   struct sk_buff **to_free);
292 	struct sk_buff *	(*dequeue)(struct Qdisc *);
293 	struct sk_buff *	(*peek)(struct Qdisc *);
294 
295 	int			(*init)(struct Qdisc *sch, struct nlattr *arg,
296 					struct netlink_ext_ack *extack);
297 	void			(*reset)(struct Qdisc *);
298 	void			(*destroy)(struct Qdisc *);
299 	int			(*change)(struct Qdisc *sch,
300 					  struct nlattr *arg,
301 					  struct netlink_ext_ack *extack);
302 	void			(*attach)(struct Qdisc *sch);
303 	int			(*change_tx_queue_len)(struct Qdisc *, unsigned int);
304 	void			(*change_real_num_tx)(struct Qdisc *sch,
305 						      unsigned int new_real_tx);
306 
307 	int			(*dump)(struct Qdisc *, struct sk_buff *);
308 	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
309 
310 	void			(*ingress_block_set)(struct Qdisc *sch,
311 						     u32 block_index);
312 	void			(*egress_block_set)(struct Qdisc *sch,
313 						    u32 block_index);
314 	u32			(*ingress_block_get)(struct Qdisc *sch);
315 	u32			(*egress_block_get)(struct Qdisc *sch);
316 
317 	struct module		*owner;
318 };
319 
320 
321 struct tcf_result {
322 	union {
323 		struct {
324 			unsigned long	class;
325 			u32		classid;
326 		};
327 		const struct tcf_proto *goto_tp;
328 
329 		/* used in the skb_tc_reinsert function */
330 		struct {
331 			bool		ingress;
332 			struct gnet_stats_queue *qstats;
333 		};
334 	};
335 };
336 
337 struct tcf_chain;
338 
339 struct tcf_proto_ops {
340 	struct list_head	head;
341 	char			kind[IFNAMSIZ];
342 
343 	int			(*classify)(struct sk_buff *,
344 					    const struct tcf_proto *,
345 					    struct tcf_result *);
346 	int			(*init)(struct tcf_proto*);
347 	void			(*destroy)(struct tcf_proto *tp, bool rtnl_held,
348 					   struct netlink_ext_ack *extack);
349 
350 	void*			(*get)(struct tcf_proto*, u32 handle);
351 	void			(*put)(struct tcf_proto *tp, void *f);
352 	int			(*change)(struct net *net, struct sk_buff *,
353 					struct tcf_proto*, unsigned long,
354 					u32 handle, struct nlattr **,
355 					void **, u32,
356 					struct netlink_ext_ack *);
357 	int			(*delete)(struct tcf_proto *tp, void *arg,
358 					  bool *last, bool rtnl_held,
359 					  struct netlink_ext_ack *);
360 	bool			(*delete_empty)(struct tcf_proto *tp);
361 	void			(*walk)(struct tcf_proto *tp,
362 					struct tcf_walker *arg, bool rtnl_held);
363 	int			(*reoffload)(struct tcf_proto *tp, bool add,
364 					     flow_setup_cb_t *cb, void *cb_priv,
365 					     struct netlink_ext_ack *extack);
366 	void			(*hw_add)(struct tcf_proto *tp,
367 					  void *type_data);
368 	void			(*hw_del)(struct tcf_proto *tp,
369 					  void *type_data);
370 	void			(*bind_class)(void *, u32, unsigned long,
371 					      void *, unsigned long);
372 	void *			(*tmplt_create)(struct net *net,
373 						struct tcf_chain *chain,
374 						struct nlattr **tca,
375 						struct netlink_ext_ack *extack);
376 	void			(*tmplt_destroy)(void *tmplt_priv);
377 
378 	/* rtnetlink specific */
379 	int			(*dump)(struct net*, struct tcf_proto*, void *,
380 					struct sk_buff *skb, struct tcmsg*,
381 					bool);
382 	int			(*terse_dump)(struct net *net,
383 					      struct tcf_proto *tp, void *fh,
384 					      struct sk_buff *skb,
385 					      struct tcmsg *t, bool rtnl_held);
386 	int			(*tmplt_dump)(struct sk_buff *skb,
387 					      struct net *net,
388 					      void *tmplt_priv);
389 
390 	struct module		*owner;
391 	int			flags;
392 };
393 
394 /* Classifiers setting TCF_PROTO_OPS_DOIT_UNLOCKED in tcf_proto_ops->flags
395  * are expected to implement tcf_proto_ops->delete_empty(), otherwise race
396  * conditions can occur when filters are inserted/deleted simultaneously.
397  */
398 enum tcf_proto_ops_flags {
399 	TCF_PROTO_OPS_DOIT_UNLOCKED = 1,
400 };
401 
402 struct tcf_proto {
403 	/* Fast access part */
404 	struct tcf_proto __rcu	*next;
405 	void __rcu		*root;
406 
407 	/* called under RCU BH lock*/
408 	int			(*classify)(struct sk_buff *,
409 					    const struct tcf_proto *,
410 					    struct tcf_result *);
411 	__be16			protocol;
412 
413 	/* All the rest */
414 	u32			prio;
415 	void			*data;
416 	const struct tcf_proto_ops	*ops;
417 	struct tcf_chain	*chain;
418 	/* Lock protects tcf_proto shared state and can be used by unlocked
419 	 * classifiers to protect their private data.
420 	 */
421 	spinlock_t		lock;
422 	bool			deleting;
423 	refcount_t		refcnt;
424 	struct rcu_head		rcu;
425 	struct hlist_node	destroy_ht_node;
426 };
427 
428 struct qdisc_skb_cb {
429 	struct {
430 		unsigned int		pkt_len;
431 		u16			slave_dev_queue_mapping;
432 		u16			tc_classid;
433 	};
434 #define QDISC_CB_PRIV_LEN 20
435 	unsigned char		data[QDISC_CB_PRIV_LEN];
436 };
437 
438 typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);
439 
440 struct tcf_chain {
441 	/* Protects filter_chain. */
442 	struct mutex filter_chain_lock;
443 	struct tcf_proto __rcu *filter_chain;
444 	struct list_head list;
445 	struct tcf_block *block;
446 	u32 index; /* chain index */
447 	unsigned int refcnt;
448 	unsigned int action_refcnt;
449 	bool explicitly_created;
450 	bool flushing;
451 	const struct tcf_proto_ops *tmplt_ops;
452 	void *tmplt_priv;
453 	struct rcu_head rcu;
454 };
455 
456 struct tcf_block {
457 	/* Lock protects tcf_block and lifetime-management data of chains
458 	 * attached to the block (refcnt, action_refcnt, explicitly_created).
459 	 */
460 	struct mutex lock;
461 	struct list_head chain_list;
462 	u32 index; /* block index for shared blocks */
463 	u32 classid; /* which class this block belongs to */
464 	refcount_t refcnt;
465 	struct net *net;
466 	struct Qdisc *q;
467 	struct rw_semaphore cb_lock; /* protects cb_list and offload counters */
468 	struct flow_block flow_block;
469 	struct list_head owner_list;
470 	bool keep_dst;
471 	atomic_t offloadcnt; /* Number of oddloaded filters */
472 	unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
473 	unsigned int lockeddevcnt; /* Number of devs that require rtnl lock. */
474 	struct {
475 		struct tcf_chain *chain;
476 		struct list_head filter_chain_list;
477 	} chain0;
478 	struct rcu_head rcu;
479 	DECLARE_HASHTABLE(proto_destroy_ht, 7);
480 	struct mutex proto_destroy_lock; /* Lock for proto_destroy hashtable. */
481 };
482 
483 static inline bool lockdep_tcf_chain_is_locked(struct tcf_chain *chain)
484 {
485 	return lockdep_is_held(&chain->filter_chain_lock);
486 }
487 
488 static inline bool lockdep_tcf_proto_is_locked(struct tcf_proto *tp)
489 {
490 	return lockdep_is_held(&tp->lock);
491 }
492 
493 #define tcf_chain_dereference(p, chain)					\
494 	rcu_dereference_protected(p, lockdep_tcf_chain_is_locked(chain))
495 
496 #define tcf_proto_dereference(p, tp)					\
497 	rcu_dereference_protected(p, lockdep_tcf_proto_is_locked(tp))
498 
499 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
500 {
501 	struct qdisc_skb_cb *qcb;
502 
503 	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*qcb));
504 	BUILD_BUG_ON(sizeof(qcb->data) < sz);
505 }
506 
507 static inline int qdisc_qlen(const struct Qdisc *q)
508 {
509 	return q->q.qlen;
510 }
511 
512 static inline int qdisc_qlen_sum(const struct Qdisc *q)
513 {
514 	__u32 qlen = q->qstats.qlen;
515 	int i;
516 
517 	if (qdisc_is_percpu_stats(q)) {
518 		for_each_possible_cpu(i)
519 			qlen += per_cpu_ptr(q->cpu_qstats, i)->qlen;
520 	} else {
521 		qlen += q->q.qlen;
522 	}
523 
524 	return qlen;
525 }
526 
527 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
528 {
529 	return (struct qdisc_skb_cb *)skb->cb;
530 }
531 
532 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
533 {
534 	return &qdisc->q.lock;
535 }
536 
537 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
538 {
539 	struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
540 
541 	return q;
542 }
543 
544 static inline struct Qdisc *qdisc_root_bh(const struct Qdisc *qdisc)
545 {
546 	return rcu_dereference_bh(qdisc->dev_queue->qdisc);
547 }
548 
549 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
550 {
551 	return qdisc->dev_queue->qdisc_sleeping;
552 }
553 
554 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
555 {
556 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
557 
558 	ASSERT_RTNL();
559 	return qdisc_lock(root);
560 }
561 
562 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
563 {
564 	return qdisc->dev_queue->dev;
565 }
566 
567 static inline void sch_tree_lock(struct Qdisc *q)
568 {
569 	if (q->flags & TCQ_F_MQROOT)
570 		spin_lock_bh(qdisc_lock(q));
571 	else
572 		spin_lock_bh(qdisc_root_sleeping_lock(q));
573 }
574 
575 static inline void sch_tree_unlock(struct Qdisc *q)
576 {
577 	if (q->flags & TCQ_F_MQROOT)
578 		spin_unlock_bh(qdisc_lock(q));
579 	else
580 		spin_unlock_bh(qdisc_root_sleeping_lock(q));
581 }
582 
583 extern struct Qdisc noop_qdisc;
584 extern struct Qdisc_ops noop_qdisc_ops;
585 extern struct Qdisc_ops pfifo_fast_ops;
586 extern struct Qdisc_ops mq_qdisc_ops;
587 extern struct Qdisc_ops noqueue_qdisc_ops;
588 extern const struct Qdisc_ops *default_qdisc_ops;
589 static inline const struct Qdisc_ops *
590 get_default_qdisc_ops(const struct net_device *dev, int ntx)
591 {
592 	return ntx < dev->real_num_tx_queues ?
593 			default_qdisc_ops : &pfifo_fast_ops;
594 }
595 
596 struct Qdisc_class_common {
597 	u32			classid;
598 	struct hlist_node	hnode;
599 };
600 
601 struct Qdisc_class_hash {
602 	struct hlist_head	*hash;
603 	unsigned int		hashsize;
604 	unsigned int		hashmask;
605 	unsigned int		hashelems;
606 };
607 
608 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
609 {
610 	id ^= id >> 8;
611 	id ^= id >> 4;
612 	return id & mask;
613 }
614 
615 static inline struct Qdisc_class_common *
616 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
617 {
618 	struct Qdisc_class_common *cl;
619 	unsigned int h;
620 
621 	if (!id)
622 		return NULL;
623 
624 	h = qdisc_class_hash(id, hash->hashmask);
625 	hlist_for_each_entry(cl, &hash->hash[h], hnode) {
626 		if (cl->classid == id)
627 			return cl;
628 	}
629 	return NULL;
630 }
631 
632 static inline int tc_classid_to_hwtc(struct net_device *dev, u32 classid)
633 {
634 	u32 hwtc = TC_H_MIN(classid) - TC_H_MIN_PRIORITY;
635 
636 	return (hwtc < netdev_get_num_tc(dev)) ? hwtc : -EINVAL;
637 }
638 
639 int qdisc_class_hash_init(struct Qdisc_class_hash *);
640 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
641 			     struct Qdisc_class_common *);
642 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
643 			     struct Qdisc_class_common *);
644 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
645 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
646 
647 int dev_qdisc_change_tx_queue_len(struct net_device *dev);
648 void dev_qdisc_change_real_num_tx(struct net_device *dev,
649 				  unsigned int new_real_tx);
650 void dev_init_scheduler(struct net_device *dev);
651 void dev_shutdown(struct net_device *dev);
652 void dev_activate(struct net_device *dev);
653 void dev_deactivate(struct net_device *dev);
654 void dev_deactivate_many(struct list_head *head);
655 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
656 			      struct Qdisc *qdisc);
657 void qdisc_reset(struct Qdisc *qdisc);
658 void qdisc_put(struct Qdisc *qdisc);
659 void qdisc_put_unlocked(struct Qdisc *qdisc);
660 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, int n, int len);
661 #ifdef CONFIG_NET_SCHED
662 int qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
663 			      void *type_data);
664 void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
665 				struct Qdisc *new, struct Qdisc *old,
666 				enum tc_setup_type type, void *type_data,
667 				struct netlink_ext_ack *extack);
668 #else
669 static inline int
670 qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
671 			  void *type_data)
672 {
673 	q->flags &= ~TCQ_F_OFFLOADED;
674 	return 0;
675 }
676 
677 static inline void
678 qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
679 			   struct Qdisc *new, struct Qdisc *old,
680 			   enum tc_setup_type type, void *type_data,
681 			   struct netlink_ext_ack *extack)
682 {
683 }
684 #endif
685 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
686 			  const struct Qdisc_ops *ops,
687 			  struct netlink_ext_ack *extack);
688 void qdisc_free(struct Qdisc *qdisc);
689 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
690 				const struct Qdisc_ops *ops, u32 parentid,
691 				struct netlink_ext_ack *extack);
692 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
693 			       const struct qdisc_size_table *stab);
694 int skb_do_redirect(struct sk_buff *);
695 
696 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
697 {
698 #ifdef CONFIG_NET_CLS_ACT
699 	return skb->tc_at_ingress;
700 #else
701 	return false;
702 #endif
703 }
704 
705 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
706 {
707 #ifdef CONFIG_NET_CLS_ACT
708 	if (skb->tc_skip_classify) {
709 		skb->tc_skip_classify = 0;
710 		return true;
711 	}
712 #endif
713 	return false;
714 }
715 
716 /* Reset all TX qdiscs greater than index of a device.  */
717 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
718 {
719 	struct Qdisc *qdisc;
720 
721 	for (; i < dev->num_tx_queues; i++) {
722 		qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
723 		if (qdisc) {
724 			spin_lock_bh(qdisc_lock(qdisc));
725 			qdisc_reset(qdisc);
726 			spin_unlock_bh(qdisc_lock(qdisc));
727 		}
728 	}
729 }
730 
731 /* Are all TX queues of the device empty?  */
732 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
733 {
734 	unsigned int i;
735 
736 	rcu_read_lock();
737 	for (i = 0; i < dev->num_tx_queues; i++) {
738 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
739 		const struct Qdisc *q = rcu_dereference(txq->qdisc);
740 
741 		if (!qdisc_is_empty(q)) {
742 			rcu_read_unlock();
743 			return false;
744 		}
745 	}
746 	rcu_read_unlock();
747 	return true;
748 }
749 
750 /* Are any of the TX qdiscs changing?  */
751 static inline bool qdisc_tx_changing(const struct net_device *dev)
752 {
753 	unsigned int i;
754 
755 	for (i = 0; i < dev->num_tx_queues; i++) {
756 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
757 		if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
758 			return true;
759 	}
760 	return false;
761 }
762 
763 /* Is the device using the noop qdisc on all queues?  */
764 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
765 {
766 	unsigned int i;
767 
768 	for (i = 0; i < dev->num_tx_queues; i++) {
769 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
770 		if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
771 			return false;
772 	}
773 	return true;
774 }
775 
776 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
777 {
778 	return qdisc_skb_cb(skb)->pkt_len;
779 }
780 
781 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
782 enum net_xmit_qdisc_t {
783 	__NET_XMIT_STOLEN = 0x00010000,
784 	__NET_XMIT_BYPASS = 0x00020000,
785 };
786 
787 #ifdef CONFIG_NET_CLS_ACT
788 #define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
789 #else
790 #define net_xmit_drop_count(e)	(1)
791 #endif
792 
793 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
794 					   const struct Qdisc *sch)
795 {
796 #ifdef CONFIG_NET_SCHED
797 	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
798 
799 	if (stab)
800 		__qdisc_calculate_pkt_len(skb, stab);
801 #endif
802 }
803 
804 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
805 				struct sk_buff **to_free)
806 {
807 	qdisc_calculate_pkt_len(skb, sch);
808 	return sch->enqueue(skb, sch, to_free);
809 }
810 
811 static inline void _bstats_update(struct gnet_stats_basic_sync *bstats,
812 				  __u64 bytes, __u32 packets)
813 {
814 	u64_stats_update_begin(&bstats->syncp);
815 	u64_stats_add(&bstats->bytes, bytes);
816 	u64_stats_add(&bstats->packets, packets);
817 	u64_stats_update_end(&bstats->syncp);
818 }
819 
820 static inline void bstats_update(struct gnet_stats_basic_sync *bstats,
821 				 const struct sk_buff *skb)
822 {
823 	_bstats_update(bstats,
824 		       qdisc_pkt_len(skb),
825 		       skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
826 }
827 
828 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
829 					   const struct sk_buff *skb)
830 {
831 	bstats_update(this_cpu_ptr(sch->cpu_bstats), skb);
832 }
833 
834 static inline void qdisc_bstats_update(struct Qdisc *sch,
835 				       const struct sk_buff *skb)
836 {
837 	bstats_update(&sch->bstats, skb);
838 }
839 
840 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
841 					    const struct sk_buff *skb)
842 {
843 	sch->qstats.backlog -= qdisc_pkt_len(skb);
844 }
845 
846 static inline void qdisc_qstats_cpu_backlog_dec(struct Qdisc *sch,
847 						const struct sk_buff *skb)
848 {
849 	this_cpu_sub(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
850 }
851 
852 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
853 					    const struct sk_buff *skb)
854 {
855 	sch->qstats.backlog += qdisc_pkt_len(skb);
856 }
857 
858 static inline void qdisc_qstats_cpu_backlog_inc(struct Qdisc *sch,
859 						const struct sk_buff *skb)
860 {
861 	this_cpu_add(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
862 }
863 
864 static inline void qdisc_qstats_cpu_qlen_inc(struct Qdisc *sch)
865 {
866 	this_cpu_inc(sch->cpu_qstats->qlen);
867 }
868 
869 static inline void qdisc_qstats_cpu_qlen_dec(struct Qdisc *sch)
870 {
871 	this_cpu_dec(sch->cpu_qstats->qlen);
872 }
873 
874 static inline void qdisc_qstats_cpu_requeues_inc(struct Qdisc *sch)
875 {
876 	this_cpu_inc(sch->cpu_qstats->requeues);
877 }
878 
879 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
880 {
881 	sch->qstats.drops += count;
882 }
883 
884 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
885 {
886 	qstats->drops++;
887 }
888 
889 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
890 {
891 	qstats->overlimits++;
892 }
893 
894 static inline void qdisc_qstats_drop(struct Qdisc *sch)
895 {
896 	qstats_drop_inc(&sch->qstats);
897 }
898 
899 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
900 {
901 	this_cpu_inc(sch->cpu_qstats->drops);
902 }
903 
904 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
905 {
906 	sch->qstats.overlimits++;
907 }
908 
909 static inline int qdisc_qstats_copy(struct gnet_dump *d, struct Qdisc *sch)
910 {
911 	__u32 qlen = qdisc_qlen_sum(sch);
912 
913 	return gnet_stats_copy_queue(d, sch->cpu_qstats, &sch->qstats, qlen);
914 }
915 
916 static inline void qdisc_qstats_qlen_backlog(struct Qdisc *sch,  __u32 *qlen,
917 					     __u32 *backlog)
918 {
919 	struct gnet_stats_queue qstats = { 0 };
920 
921 	gnet_stats_add_queue(&qstats, sch->cpu_qstats, &sch->qstats);
922 	*qlen = qstats.qlen + qdisc_qlen(sch);
923 	*backlog = qstats.backlog;
924 }
925 
926 static inline void qdisc_tree_flush_backlog(struct Qdisc *sch)
927 {
928 	__u32 qlen, backlog;
929 
930 	qdisc_qstats_qlen_backlog(sch, &qlen, &backlog);
931 	qdisc_tree_reduce_backlog(sch, qlen, backlog);
932 }
933 
934 static inline void qdisc_purge_queue(struct Qdisc *sch)
935 {
936 	__u32 qlen, backlog;
937 
938 	qdisc_qstats_qlen_backlog(sch, &qlen, &backlog);
939 	qdisc_reset(sch);
940 	qdisc_tree_reduce_backlog(sch, qlen, backlog);
941 }
942 
943 static inline void __qdisc_enqueue_tail(struct sk_buff *skb,
944 					struct qdisc_skb_head *qh)
945 {
946 	struct sk_buff *last = qh->tail;
947 
948 	if (last) {
949 		skb->next = NULL;
950 		last->next = skb;
951 		qh->tail = skb;
952 	} else {
953 		qh->tail = skb;
954 		qh->head = skb;
955 	}
956 	qh->qlen++;
957 }
958 
959 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
960 {
961 	__qdisc_enqueue_tail(skb, &sch->q);
962 	qdisc_qstats_backlog_inc(sch, skb);
963 	return NET_XMIT_SUCCESS;
964 }
965 
966 static inline void __qdisc_enqueue_head(struct sk_buff *skb,
967 					struct qdisc_skb_head *qh)
968 {
969 	skb->next = qh->head;
970 
971 	if (!qh->head)
972 		qh->tail = skb;
973 	qh->head = skb;
974 	qh->qlen++;
975 }
976 
977 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
978 {
979 	struct sk_buff *skb = qh->head;
980 
981 	if (likely(skb != NULL)) {
982 		qh->head = skb->next;
983 		qh->qlen--;
984 		if (qh->head == NULL)
985 			qh->tail = NULL;
986 		skb->next = NULL;
987 	}
988 
989 	return skb;
990 }
991 
992 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
993 {
994 	struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
995 
996 	if (likely(skb != NULL)) {
997 		qdisc_qstats_backlog_dec(sch, skb);
998 		qdisc_bstats_update(sch, skb);
999 	}
1000 
1001 	return skb;
1002 }
1003 
1004 /* Instead of calling kfree_skb() while root qdisc lock is held,
1005  * queue the skb for future freeing at end of __dev_xmit_skb()
1006  */
1007 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
1008 {
1009 	skb->next = *to_free;
1010 	*to_free = skb;
1011 }
1012 
1013 static inline void __qdisc_drop_all(struct sk_buff *skb,
1014 				    struct sk_buff **to_free)
1015 {
1016 	if (skb->prev)
1017 		skb->prev->next = *to_free;
1018 	else
1019 		skb->next = *to_free;
1020 	*to_free = skb;
1021 }
1022 
1023 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
1024 						   struct qdisc_skb_head *qh,
1025 						   struct sk_buff **to_free)
1026 {
1027 	struct sk_buff *skb = __qdisc_dequeue_head(qh);
1028 
1029 	if (likely(skb != NULL)) {
1030 		unsigned int len = qdisc_pkt_len(skb);
1031 
1032 		qdisc_qstats_backlog_dec(sch, skb);
1033 		__qdisc_drop(skb, to_free);
1034 		return len;
1035 	}
1036 
1037 	return 0;
1038 }
1039 
1040 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
1041 {
1042 	const struct qdisc_skb_head *qh = &sch->q;
1043 
1044 	return qh->head;
1045 }
1046 
1047 /* generic pseudo peek method for non-work-conserving qdisc */
1048 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
1049 {
1050 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
1051 
1052 	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
1053 	if (!skb) {
1054 		skb = sch->dequeue(sch);
1055 
1056 		if (skb) {
1057 			__skb_queue_head(&sch->gso_skb, skb);
1058 			/* it's still part of the queue */
1059 			qdisc_qstats_backlog_inc(sch, skb);
1060 			sch->q.qlen++;
1061 		}
1062 	}
1063 
1064 	return skb;
1065 }
1066 
1067 static inline void qdisc_update_stats_at_dequeue(struct Qdisc *sch,
1068 						 struct sk_buff *skb)
1069 {
1070 	if (qdisc_is_percpu_stats(sch)) {
1071 		qdisc_qstats_cpu_backlog_dec(sch, skb);
1072 		qdisc_bstats_cpu_update(sch, skb);
1073 		qdisc_qstats_cpu_qlen_dec(sch);
1074 	} else {
1075 		qdisc_qstats_backlog_dec(sch, skb);
1076 		qdisc_bstats_update(sch, skb);
1077 		sch->q.qlen--;
1078 	}
1079 }
1080 
1081 static inline void qdisc_update_stats_at_enqueue(struct Qdisc *sch,
1082 						 unsigned int pkt_len)
1083 {
1084 	if (qdisc_is_percpu_stats(sch)) {
1085 		qdisc_qstats_cpu_qlen_inc(sch);
1086 		this_cpu_add(sch->cpu_qstats->backlog, pkt_len);
1087 	} else {
1088 		sch->qstats.backlog += pkt_len;
1089 		sch->q.qlen++;
1090 	}
1091 }
1092 
1093 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
1094 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
1095 {
1096 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
1097 
1098 	if (skb) {
1099 		skb = __skb_dequeue(&sch->gso_skb);
1100 		if (qdisc_is_percpu_stats(sch)) {
1101 			qdisc_qstats_cpu_backlog_dec(sch, skb);
1102 			qdisc_qstats_cpu_qlen_dec(sch);
1103 		} else {
1104 			qdisc_qstats_backlog_dec(sch, skb);
1105 			sch->q.qlen--;
1106 		}
1107 	} else {
1108 		skb = sch->dequeue(sch);
1109 	}
1110 
1111 	return skb;
1112 }
1113 
1114 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
1115 {
1116 	/*
1117 	 * We do not know the backlog in bytes of this list, it
1118 	 * is up to the caller to correct it
1119 	 */
1120 	ASSERT_RTNL();
1121 	if (qh->qlen) {
1122 		rtnl_kfree_skbs(qh->head, qh->tail);
1123 
1124 		qh->head = NULL;
1125 		qh->tail = NULL;
1126 		qh->qlen = 0;
1127 	}
1128 }
1129 
1130 static inline void qdisc_reset_queue(struct Qdisc *sch)
1131 {
1132 	__qdisc_reset_queue(&sch->q);
1133 }
1134 
1135 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
1136 					  struct Qdisc **pold)
1137 {
1138 	struct Qdisc *old;
1139 
1140 	sch_tree_lock(sch);
1141 	old = *pold;
1142 	*pold = new;
1143 	if (old != NULL)
1144 		qdisc_purge_queue(old);
1145 	sch_tree_unlock(sch);
1146 
1147 	return old;
1148 }
1149 
1150 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
1151 {
1152 	rtnl_kfree_skbs(skb, skb);
1153 	qdisc_qstats_drop(sch);
1154 }
1155 
1156 static inline int qdisc_drop_cpu(struct sk_buff *skb, struct Qdisc *sch,
1157 				 struct sk_buff **to_free)
1158 {
1159 	__qdisc_drop(skb, to_free);
1160 	qdisc_qstats_cpu_drop(sch);
1161 
1162 	return NET_XMIT_DROP;
1163 }
1164 
1165 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
1166 			     struct sk_buff **to_free)
1167 {
1168 	__qdisc_drop(skb, to_free);
1169 	qdisc_qstats_drop(sch);
1170 
1171 	return NET_XMIT_DROP;
1172 }
1173 
1174 static inline int qdisc_drop_all(struct sk_buff *skb, struct Qdisc *sch,
1175 				 struct sk_buff **to_free)
1176 {
1177 	__qdisc_drop_all(skb, to_free);
1178 	qdisc_qstats_drop(sch);
1179 
1180 	return NET_XMIT_DROP;
1181 }
1182 
1183 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
1184    long it will take to send a packet given its size.
1185  */
1186 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
1187 {
1188 	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
1189 	if (slot < 0)
1190 		slot = 0;
1191 	slot >>= rtab->rate.cell_log;
1192 	if (slot > 255)
1193 		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
1194 	return rtab->data[slot];
1195 }
1196 
1197 struct psched_ratecfg {
1198 	u64	rate_bytes_ps; /* bytes per second */
1199 	u32	mult;
1200 	u16	overhead;
1201 	u16	mpu;
1202 	u8	linklayer;
1203 	u8	shift;
1204 };
1205 
1206 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
1207 				unsigned int len)
1208 {
1209 	len += r->overhead;
1210 
1211 	if (len < r->mpu)
1212 		len = r->mpu;
1213 
1214 	if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
1215 		return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
1216 
1217 	return ((u64)len * r->mult) >> r->shift;
1218 }
1219 
1220 void psched_ratecfg_precompute(struct psched_ratecfg *r,
1221 			       const struct tc_ratespec *conf,
1222 			       u64 rate64);
1223 
1224 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
1225 					  const struct psched_ratecfg *r)
1226 {
1227 	memset(res, 0, sizeof(*res));
1228 
1229 	/* legacy struct tc_ratespec has a 32bit @rate field
1230 	 * Qdisc using 64bit rate should add new attributes
1231 	 * in order to maintain compatibility.
1232 	 */
1233 	res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
1234 
1235 	res->overhead = r->overhead;
1236 	res->mpu = r->mpu;
1237 	res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
1238 }
1239 
1240 struct psched_pktrate {
1241 	u64	rate_pkts_ps; /* packets per second */
1242 	u32	mult;
1243 	u8	shift;
1244 };
1245 
1246 static inline u64 psched_pkt2t_ns(const struct psched_pktrate *r,
1247 				  unsigned int pkt_num)
1248 {
1249 	return ((u64)pkt_num * r->mult) >> r->shift;
1250 }
1251 
1252 void psched_ppscfg_precompute(struct psched_pktrate *r, u64 pktrate64);
1253 
1254 /* Mini Qdisc serves for specific needs of ingress/clsact Qdisc.
1255  * The fast path only needs to access filter list and to update stats
1256  */
1257 struct mini_Qdisc {
1258 	struct tcf_proto *filter_list;
1259 	struct tcf_block *block;
1260 	struct gnet_stats_basic_sync __percpu *cpu_bstats;
1261 	struct gnet_stats_queue	__percpu *cpu_qstats;
1262 	unsigned long rcu_state;
1263 };
1264 
1265 static inline void mini_qdisc_bstats_cpu_update(struct mini_Qdisc *miniq,
1266 						const struct sk_buff *skb)
1267 {
1268 	bstats_update(this_cpu_ptr(miniq->cpu_bstats), skb);
1269 }
1270 
1271 static inline void mini_qdisc_qstats_cpu_drop(struct mini_Qdisc *miniq)
1272 {
1273 	this_cpu_inc(miniq->cpu_qstats->drops);
1274 }
1275 
1276 struct mini_Qdisc_pair {
1277 	struct mini_Qdisc miniq1;
1278 	struct mini_Qdisc miniq2;
1279 	struct mini_Qdisc __rcu **p_miniq;
1280 };
1281 
1282 void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
1283 			  struct tcf_proto *tp_head);
1284 void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
1285 			  struct mini_Qdisc __rcu **p_miniq);
1286 void mini_qdisc_pair_block_init(struct mini_Qdisc_pair *miniqp,
1287 				struct tcf_block *block);
1288 
1289 void mq_change_real_num_tx(struct Qdisc *sch, unsigned int new_real_tx);
1290 
1291 int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb));
1292 
1293 #endif
1294