xref: /openbmc/linux/include/net/sch_generic.h (revision 8440bb9b)
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 <net/gen_stats.h>
17 #include <net/rtnetlink.h>
18 
19 struct Qdisc_ops;
20 struct qdisc_walker;
21 struct tcf_walker;
22 struct module;
23 struct bpf_flow_keys;
24 
25 typedef int tc_setup_cb_t(enum tc_setup_type type,
26 			  void *type_data, void *cb_priv);
27 
28 typedef int tc_indr_block_bind_cb_t(struct net_device *dev, void *cb_priv,
29 				    enum tc_setup_type type, void *type_data);
30 
31 struct qdisc_rate_table {
32 	struct tc_ratespec rate;
33 	u32		data[256];
34 	struct qdisc_rate_table *next;
35 	int		refcnt;
36 };
37 
38 enum qdisc_state_t {
39 	__QDISC_STATE_SCHED,
40 	__QDISC_STATE_DEACTIVATED,
41 };
42 
43 struct qdisc_size_table {
44 	struct rcu_head		rcu;
45 	struct list_head	list;
46 	struct tc_sizespec	szopts;
47 	int			refcnt;
48 	u16			data[];
49 };
50 
51 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
52 struct qdisc_skb_head {
53 	struct sk_buff	*head;
54 	struct sk_buff	*tail;
55 	union {
56 		u32		qlen;
57 		atomic_t	atomic_qlen;
58 	};
59 	spinlock_t	lock;
60 };
61 
62 struct Qdisc {
63 	int 			(*enqueue)(struct sk_buff *skb,
64 					   struct Qdisc *sch,
65 					   struct sk_buff **to_free);
66 	struct sk_buff *	(*dequeue)(struct Qdisc *sch);
67 	unsigned int		flags;
68 #define TCQ_F_BUILTIN		1
69 #define TCQ_F_INGRESS		2
70 #define TCQ_F_CAN_BYPASS	4
71 #define TCQ_F_MQROOT		8
72 #define TCQ_F_ONETXQUEUE	0x10 /* dequeue_skb() can assume all skbs are for
73 				      * q->dev_queue : It can test
74 				      * netif_xmit_frozen_or_stopped() before
75 				      * dequeueing next packet.
76 				      * Its true for MQ/MQPRIO slaves, or non
77 				      * multiqueue device.
78 				      */
79 #define TCQ_F_WARN_NONWC	(1 << 16)
80 #define TCQ_F_CPUSTATS		0x20 /* run using percpu statistics */
81 #define TCQ_F_NOPARENT		0x40 /* root of its hierarchy :
82 				      * qdisc_tree_decrease_qlen() should stop.
83 				      */
84 #define TCQ_F_INVISIBLE		0x80 /* invisible by default in dump */
85 #define TCQ_F_NOLOCK		0x100 /* qdisc does not require locking */
86 #define TCQ_F_OFFLOADED		0x200 /* qdisc is offloaded to HW */
87 	u32			limit;
88 	const struct Qdisc_ops	*ops;
89 	struct qdisc_size_table	__rcu *stab;
90 	struct hlist_node       hash;
91 	u32			handle;
92 	u32			parent;
93 
94 	struct netdev_queue	*dev_queue;
95 
96 	struct net_rate_estimator __rcu *rate_est;
97 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
98 	struct gnet_stats_queue	__percpu *cpu_qstats;
99 	int			padded;
100 	refcount_t		refcnt;
101 
102 	/*
103 	 * For performance sake on SMP, we put highly modified fields at the end
104 	 */
105 	struct sk_buff_head	gso_skb ____cacheline_aligned_in_smp;
106 	struct qdisc_skb_head	q;
107 	struct gnet_stats_basic_packed bstats;
108 	seqcount_t		running;
109 	struct gnet_stats_queue	qstats;
110 	unsigned long		state;
111 	struct Qdisc            *next_sched;
112 	struct sk_buff_head	skb_bad_txq;
113 
114 	spinlock_t		busylock ____cacheline_aligned_in_smp;
115 	spinlock_t		seqlock;
116 	struct rcu_head		rcu;
117 };
118 
119 static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
120 {
121 	if (qdisc->flags & TCQ_F_BUILTIN)
122 		return;
123 	refcount_inc(&qdisc->refcnt);
124 }
125 
126 /* Intended to be used by unlocked users, when concurrent qdisc release is
127  * possible.
128  */
129 
130 static inline struct Qdisc *qdisc_refcount_inc_nz(struct Qdisc *qdisc)
131 {
132 	if (qdisc->flags & TCQ_F_BUILTIN)
133 		return qdisc;
134 	if (refcount_inc_not_zero(&qdisc->refcnt))
135 		return qdisc;
136 	return NULL;
137 }
138 
139 static inline bool qdisc_is_running(struct Qdisc *qdisc)
140 {
141 	if (qdisc->flags & TCQ_F_NOLOCK)
142 		return spin_is_locked(&qdisc->seqlock);
143 	return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
144 }
145 
146 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
147 {
148 	if (qdisc->flags & TCQ_F_NOLOCK) {
149 		if (!spin_trylock(&qdisc->seqlock))
150 			return false;
151 	} else if (qdisc_is_running(qdisc)) {
152 		return false;
153 	}
154 	/* Variant of write_seqcount_begin() telling lockdep a trylock
155 	 * was attempted.
156 	 */
157 	raw_write_seqcount_begin(&qdisc->running);
158 	seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
159 	return true;
160 }
161 
162 static inline void qdisc_run_end(struct Qdisc *qdisc)
163 {
164 	write_seqcount_end(&qdisc->running);
165 	if (qdisc->flags & TCQ_F_NOLOCK)
166 		spin_unlock(&qdisc->seqlock);
167 }
168 
169 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
170 {
171 	return qdisc->flags & TCQ_F_ONETXQUEUE;
172 }
173 
174 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
175 {
176 #ifdef CONFIG_BQL
177 	/* Non-BQL migrated drivers will return 0, too. */
178 	return dql_avail(&txq->dql);
179 #else
180 	return 0;
181 #endif
182 }
183 
184 struct Qdisc_class_ops {
185 	unsigned int		flags;
186 	/* Child qdisc manipulation */
187 	struct netdev_queue *	(*select_queue)(struct Qdisc *, struct tcmsg *);
188 	int			(*graft)(struct Qdisc *, unsigned long cl,
189 					struct Qdisc *, struct Qdisc **,
190 					struct netlink_ext_ack *extack);
191 	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
192 	void			(*qlen_notify)(struct Qdisc *, unsigned long);
193 
194 	/* Class manipulation routines */
195 	unsigned long		(*find)(struct Qdisc *, u32 classid);
196 	int			(*change)(struct Qdisc *, u32, u32,
197 					struct nlattr **, unsigned long *,
198 					struct netlink_ext_ack *);
199 	int			(*delete)(struct Qdisc *, unsigned long);
200 	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
201 
202 	/* Filter manipulation */
203 	struct tcf_block *	(*tcf_block)(struct Qdisc *sch,
204 					     unsigned long arg,
205 					     struct netlink_ext_ack *extack);
206 	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
207 					u32 classid);
208 	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
209 
210 	/* rtnetlink specific */
211 	int			(*dump)(struct Qdisc *, unsigned long,
212 					struct sk_buff *skb, struct tcmsg*);
213 	int			(*dump_stats)(struct Qdisc *, unsigned long,
214 					struct gnet_dump *);
215 };
216 
217 /* Qdisc_class_ops flag values */
218 
219 /* Implements API that doesn't require rtnl lock */
220 enum qdisc_class_ops_flags {
221 	QDISC_CLASS_OPS_DOIT_UNLOCKED = 1,
222 };
223 
224 struct Qdisc_ops {
225 	struct Qdisc_ops	*next;
226 	const struct Qdisc_class_ops	*cl_ops;
227 	char			id[IFNAMSIZ];
228 	int			priv_size;
229 	unsigned int		static_flags;
230 
231 	int 			(*enqueue)(struct sk_buff *skb,
232 					   struct Qdisc *sch,
233 					   struct sk_buff **to_free);
234 	struct sk_buff *	(*dequeue)(struct Qdisc *);
235 	struct sk_buff *	(*peek)(struct Qdisc *);
236 
237 	int			(*init)(struct Qdisc *sch, struct nlattr *arg,
238 					struct netlink_ext_ack *extack);
239 	void			(*reset)(struct Qdisc *);
240 	void			(*destroy)(struct Qdisc *);
241 	int			(*change)(struct Qdisc *sch,
242 					  struct nlattr *arg,
243 					  struct netlink_ext_ack *extack);
244 	void			(*attach)(struct Qdisc *sch);
245 	int			(*change_tx_queue_len)(struct Qdisc *, unsigned int);
246 
247 	int			(*dump)(struct Qdisc *, struct sk_buff *);
248 	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
249 
250 	void			(*ingress_block_set)(struct Qdisc *sch,
251 						     u32 block_index);
252 	void			(*egress_block_set)(struct Qdisc *sch,
253 						    u32 block_index);
254 	u32			(*ingress_block_get)(struct Qdisc *sch);
255 	u32			(*egress_block_get)(struct Qdisc *sch);
256 
257 	struct module		*owner;
258 };
259 
260 
261 struct tcf_result {
262 	union {
263 		struct {
264 			unsigned long	class;
265 			u32		classid;
266 		};
267 		const struct tcf_proto *goto_tp;
268 
269 		/* used by the TC_ACT_REINSERT action */
270 		struct {
271 			bool		ingress;
272 			struct gnet_stats_queue *qstats;
273 		};
274 	};
275 };
276 
277 struct tcf_chain;
278 
279 struct tcf_proto_ops {
280 	struct list_head	head;
281 	char			kind[IFNAMSIZ];
282 
283 	int			(*classify)(struct sk_buff *,
284 					    const struct tcf_proto *,
285 					    struct tcf_result *);
286 	int			(*init)(struct tcf_proto*);
287 	void			(*destroy)(struct tcf_proto *tp, bool rtnl_held,
288 					   struct netlink_ext_ack *extack);
289 
290 	void*			(*get)(struct tcf_proto*, u32 handle);
291 	void			(*put)(struct tcf_proto *tp, void *f);
292 	int			(*change)(struct net *net, struct sk_buff *,
293 					struct tcf_proto*, unsigned long,
294 					u32 handle, struct nlattr **,
295 					void **, bool, bool,
296 					struct netlink_ext_ack *);
297 	int			(*delete)(struct tcf_proto *tp, void *arg,
298 					  bool *last, bool rtnl_held,
299 					  struct netlink_ext_ack *);
300 	void			(*walk)(struct tcf_proto *tp,
301 					struct tcf_walker *arg, bool rtnl_held);
302 	int			(*reoffload)(struct tcf_proto *tp, bool add,
303 					     tc_setup_cb_t *cb, void *cb_priv,
304 					     struct netlink_ext_ack *extack);
305 	void			(*bind_class)(void *, u32, unsigned long);
306 	void *			(*tmplt_create)(struct net *net,
307 						struct tcf_chain *chain,
308 						struct nlattr **tca,
309 						struct netlink_ext_ack *extack);
310 	void			(*tmplt_destroy)(void *tmplt_priv);
311 
312 	/* rtnetlink specific */
313 	int			(*dump)(struct net*, struct tcf_proto*, void *,
314 					struct sk_buff *skb, struct tcmsg*,
315 					bool);
316 	int			(*tmplt_dump)(struct sk_buff *skb,
317 					      struct net *net,
318 					      void *tmplt_priv);
319 
320 	struct module		*owner;
321 	int			flags;
322 };
323 
324 enum tcf_proto_ops_flags {
325 	TCF_PROTO_OPS_DOIT_UNLOCKED = 1,
326 };
327 
328 struct tcf_proto {
329 	/* Fast access part */
330 	struct tcf_proto __rcu	*next;
331 	void __rcu		*root;
332 
333 	/* called under RCU BH lock*/
334 	int			(*classify)(struct sk_buff *,
335 					    const struct tcf_proto *,
336 					    struct tcf_result *);
337 	__be16			protocol;
338 
339 	/* All the rest */
340 	u32			prio;
341 	void			*data;
342 	const struct tcf_proto_ops	*ops;
343 	struct tcf_chain	*chain;
344 	/* Lock protects tcf_proto shared state and can be used by unlocked
345 	 * classifiers to protect their private data.
346 	 */
347 	spinlock_t		lock;
348 	bool			deleting;
349 	refcount_t		refcnt;
350 	struct rcu_head		rcu;
351 };
352 
353 struct qdisc_skb_cb {
354 	union {
355 		struct {
356 			unsigned int		pkt_len;
357 			u16			slave_dev_queue_mapping;
358 			u16			tc_classid;
359 		};
360 		struct bpf_flow_keys *flow_keys;
361 	};
362 #define QDISC_CB_PRIV_LEN 20
363 	unsigned char		data[QDISC_CB_PRIV_LEN];
364 };
365 
366 typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);
367 
368 struct tcf_chain {
369 	/* Protects filter_chain. */
370 	struct mutex filter_chain_lock;
371 	struct tcf_proto __rcu *filter_chain;
372 	struct list_head list;
373 	struct tcf_block *block;
374 	u32 index; /* chain index */
375 	unsigned int refcnt;
376 	unsigned int action_refcnt;
377 	bool explicitly_created;
378 	bool flushing;
379 	const struct tcf_proto_ops *tmplt_ops;
380 	void *tmplt_priv;
381 };
382 
383 struct tcf_block {
384 	/* Lock protects tcf_block and lifetime-management data of chains
385 	 * attached to the block (refcnt, action_refcnt, explicitly_created).
386 	 */
387 	struct mutex lock;
388 	struct list_head chain_list;
389 	u32 index; /* block index for shared blocks */
390 	refcount_t refcnt;
391 	struct net *net;
392 	struct Qdisc *q;
393 	struct list_head cb_list;
394 	struct list_head owner_list;
395 	bool keep_dst;
396 	unsigned int offloadcnt; /* Number of oddloaded filters */
397 	unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
398 	struct {
399 		struct tcf_chain *chain;
400 		struct list_head filter_chain_list;
401 	} chain0;
402 	struct rcu_head rcu;
403 };
404 
405 #ifdef CONFIG_PROVE_LOCKING
406 static inline bool lockdep_tcf_chain_is_locked(struct tcf_chain *chain)
407 {
408 	return lockdep_is_held(&chain->filter_chain_lock);
409 }
410 
411 static inline bool lockdep_tcf_proto_is_locked(struct tcf_proto *tp)
412 {
413 	return lockdep_is_held(&tp->lock);
414 }
415 #else
416 static inline bool lockdep_tcf_chain_is_locked(struct tcf_block *chain)
417 {
418 	return true;
419 }
420 
421 static inline bool lockdep_tcf_proto_is_locked(struct tcf_proto *tp)
422 {
423 	return true;
424 }
425 #endif /* #ifdef CONFIG_PROVE_LOCKING */
426 
427 #define tcf_chain_dereference(p, chain)					\
428 	rcu_dereference_protected(p, lockdep_tcf_chain_is_locked(chain))
429 
430 #define tcf_proto_dereference(p, tp)					\
431 	rcu_dereference_protected(p, lockdep_tcf_proto_is_locked(tp))
432 
433 static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
434 {
435 	if (*flags & TCA_CLS_FLAGS_IN_HW)
436 		return;
437 	*flags |= TCA_CLS_FLAGS_IN_HW;
438 	block->offloadcnt++;
439 }
440 
441 static inline void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
442 {
443 	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
444 		return;
445 	*flags &= ~TCA_CLS_FLAGS_IN_HW;
446 	block->offloadcnt--;
447 }
448 
449 static inline void
450 tc_cls_offload_cnt_update(struct tcf_block *block, u32 *cnt,
451 			  u32 *flags, bool add)
452 {
453 	if (add) {
454 		if (!*cnt)
455 			tcf_block_offload_inc(block, flags);
456 		(*cnt)++;
457 	} else {
458 		(*cnt)--;
459 		if (!*cnt)
460 			tcf_block_offload_dec(block, flags);
461 	}
462 }
463 
464 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
465 {
466 	struct qdisc_skb_cb *qcb;
467 
468 	BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
469 	BUILD_BUG_ON(sizeof(qcb->data) < sz);
470 }
471 
472 static inline int qdisc_qlen(const struct Qdisc *q)
473 {
474 	return q->q.qlen;
475 }
476 
477 static inline u32 qdisc_qlen_sum(const struct Qdisc *q)
478 {
479 	u32 qlen = q->qstats.qlen;
480 
481 	if (q->flags & TCQ_F_NOLOCK)
482 		qlen += atomic_read(&q->q.atomic_qlen);
483 	else
484 		qlen += q->q.qlen;
485 
486 	return qlen;
487 }
488 
489 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
490 {
491 	return (struct qdisc_skb_cb *)skb->cb;
492 }
493 
494 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
495 {
496 	return &qdisc->q.lock;
497 }
498 
499 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
500 {
501 	struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
502 
503 	return q;
504 }
505 
506 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
507 {
508 	return qdisc->dev_queue->qdisc_sleeping;
509 }
510 
511 /* The qdisc root lock is a mechanism by which to top level
512  * of a qdisc tree can be locked from any qdisc node in the
513  * forest.  This allows changing the configuration of some
514  * aspect of the qdisc tree while blocking out asynchronous
515  * qdisc access in the packet processing paths.
516  *
517  * It is only legal to do this when the root will not change
518  * on us.  Otherwise we'll potentially lock the wrong qdisc
519  * root.  This is enforced by holding the RTNL semaphore, which
520  * all users of this lock accessor must do.
521  */
522 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
523 {
524 	struct Qdisc *root = qdisc_root(qdisc);
525 
526 	ASSERT_RTNL();
527 	return qdisc_lock(root);
528 }
529 
530 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
531 {
532 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
533 
534 	ASSERT_RTNL();
535 	return qdisc_lock(root);
536 }
537 
538 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
539 {
540 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
541 
542 	ASSERT_RTNL();
543 	return &root->running;
544 }
545 
546 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
547 {
548 	return qdisc->dev_queue->dev;
549 }
550 
551 static inline void sch_tree_lock(const struct Qdisc *q)
552 {
553 	spin_lock_bh(qdisc_root_sleeping_lock(q));
554 }
555 
556 static inline void sch_tree_unlock(const struct Qdisc *q)
557 {
558 	spin_unlock_bh(qdisc_root_sleeping_lock(q));
559 }
560 
561 extern struct Qdisc noop_qdisc;
562 extern struct Qdisc_ops noop_qdisc_ops;
563 extern struct Qdisc_ops pfifo_fast_ops;
564 extern struct Qdisc_ops mq_qdisc_ops;
565 extern struct Qdisc_ops noqueue_qdisc_ops;
566 extern const struct Qdisc_ops *default_qdisc_ops;
567 static inline const struct Qdisc_ops *
568 get_default_qdisc_ops(const struct net_device *dev, int ntx)
569 {
570 	return ntx < dev->real_num_tx_queues ?
571 			default_qdisc_ops : &pfifo_fast_ops;
572 }
573 
574 struct Qdisc_class_common {
575 	u32			classid;
576 	struct hlist_node	hnode;
577 };
578 
579 struct Qdisc_class_hash {
580 	struct hlist_head	*hash;
581 	unsigned int		hashsize;
582 	unsigned int		hashmask;
583 	unsigned int		hashelems;
584 };
585 
586 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
587 {
588 	id ^= id >> 8;
589 	id ^= id >> 4;
590 	return id & mask;
591 }
592 
593 static inline struct Qdisc_class_common *
594 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
595 {
596 	struct Qdisc_class_common *cl;
597 	unsigned int h;
598 
599 	if (!id)
600 		return NULL;
601 
602 	h = qdisc_class_hash(id, hash->hashmask);
603 	hlist_for_each_entry(cl, &hash->hash[h], hnode) {
604 		if (cl->classid == id)
605 			return cl;
606 	}
607 	return NULL;
608 }
609 
610 static inline int tc_classid_to_hwtc(struct net_device *dev, u32 classid)
611 {
612 	u32 hwtc = TC_H_MIN(classid) - TC_H_MIN_PRIORITY;
613 
614 	return (hwtc < netdev_get_num_tc(dev)) ? hwtc : -EINVAL;
615 }
616 
617 int qdisc_class_hash_init(struct Qdisc_class_hash *);
618 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
619 			     struct Qdisc_class_common *);
620 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
621 			     struct Qdisc_class_common *);
622 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
623 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
624 
625 int dev_qdisc_change_tx_queue_len(struct net_device *dev);
626 void dev_init_scheduler(struct net_device *dev);
627 void dev_shutdown(struct net_device *dev);
628 void dev_activate(struct net_device *dev);
629 void dev_deactivate(struct net_device *dev);
630 void dev_deactivate_many(struct list_head *head);
631 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
632 			      struct Qdisc *qdisc);
633 void qdisc_reset(struct Qdisc *qdisc);
634 void qdisc_put(struct Qdisc *qdisc);
635 void qdisc_put_unlocked(struct Qdisc *qdisc);
636 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, int n, int len);
637 #ifdef CONFIG_NET_SCHED
638 int qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
639 			      void *type_data);
640 void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
641 				struct Qdisc *new, struct Qdisc *old,
642 				enum tc_setup_type type, void *type_data,
643 				struct netlink_ext_ack *extack);
644 #else
645 static inline int
646 qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
647 			  void *type_data)
648 {
649 	q->flags &= ~TCQ_F_OFFLOADED;
650 	return 0;
651 }
652 
653 static inline void
654 qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
655 			   struct Qdisc *new, struct Qdisc *old,
656 			   enum tc_setup_type type, void *type_data,
657 			   struct netlink_ext_ack *extack)
658 {
659 }
660 #endif
661 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
662 			  const struct Qdisc_ops *ops,
663 			  struct netlink_ext_ack *extack);
664 void qdisc_free(struct Qdisc *qdisc);
665 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
666 				const struct Qdisc_ops *ops, u32 parentid,
667 				struct netlink_ext_ack *extack);
668 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
669 			       const struct qdisc_size_table *stab);
670 int skb_do_redirect(struct sk_buff *);
671 
672 static inline void skb_reset_tc(struct sk_buff *skb)
673 {
674 #ifdef CONFIG_NET_CLS_ACT
675 	skb->tc_redirected = 0;
676 #endif
677 }
678 
679 static inline bool skb_is_tc_redirected(const struct sk_buff *skb)
680 {
681 #ifdef CONFIG_NET_CLS_ACT
682 	return skb->tc_redirected;
683 #else
684 	return false;
685 #endif
686 }
687 
688 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
689 {
690 #ifdef CONFIG_NET_CLS_ACT
691 	return skb->tc_at_ingress;
692 #else
693 	return false;
694 #endif
695 }
696 
697 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
698 {
699 #ifdef CONFIG_NET_CLS_ACT
700 	if (skb->tc_skip_classify) {
701 		skb->tc_skip_classify = 0;
702 		return true;
703 	}
704 #endif
705 	return false;
706 }
707 
708 /* Reset all TX qdiscs greater than index of a device.  */
709 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
710 {
711 	struct Qdisc *qdisc;
712 
713 	for (; i < dev->num_tx_queues; i++) {
714 		qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
715 		if (qdisc) {
716 			spin_lock_bh(qdisc_lock(qdisc));
717 			qdisc_reset(qdisc);
718 			spin_unlock_bh(qdisc_lock(qdisc));
719 		}
720 	}
721 }
722 
723 static inline void qdisc_reset_all_tx(struct net_device *dev)
724 {
725 	qdisc_reset_all_tx_gt(dev, 0);
726 }
727 
728 /* Are all TX queues of the device empty?  */
729 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
730 {
731 	unsigned int i;
732 
733 	rcu_read_lock();
734 	for (i = 0; i < dev->num_tx_queues; i++) {
735 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
736 		const struct Qdisc *q = rcu_dereference(txq->qdisc);
737 
738 		if (q->q.qlen) {
739 			rcu_read_unlock();
740 			return false;
741 		}
742 	}
743 	rcu_read_unlock();
744 	return true;
745 }
746 
747 /* Are any of the TX qdiscs changing?  */
748 static inline bool qdisc_tx_changing(const struct net_device *dev)
749 {
750 	unsigned int i;
751 
752 	for (i = 0; i < dev->num_tx_queues; i++) {
753 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
754 		if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
755 			return true;
756 	}
757 	return false;
758 }
759 
760 /* Is the device using the noop qdisc on all queues?  */
761 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
762 {
763 	unsigned int i;
764 
765 	for (i = 0; i < dev->num_tx_queues; i++) {
766 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
767 		if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
768 			return false;
769 	}
770 	return true;
771 }
772 
773 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
774 {
775 	return qdisc_skb_cb(skb)->pkt_len;
776 }
777 
778 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
779 enum net_xmit_qdisc_t {
780 	__NET_XMIT_STOLEN = 0x00010000,
781 	__NET_XMIT_BYPASS = 0x00020000,
782 };
783 
784 #ifdef CONFIG_NET_CLS_ACT
785 #define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
786 #else
787 #define net_xmit_drop_count(e)	(1)
788 #endif
789 
790 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
791 					   const struct Qdisc *sch)
792 {
793 #ifdef CONFIG_NET_SCHED
794 	struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
795 
796 	if (stab)
797 		__qdisc_calculate_pkt_len(skb, stab);
798 #endif
799 }
800 
801 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
802 				struct sk_buff **to_free)
803 {
804 	qdisc_calculate_pkt_len(skb, sch);
805 	return sch->enqueue(skb, sch, to_free);
806 }
807 
808 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
809 {
810 	return q->flags & TCQ_F_CPUSTATS;
811 }
812 
813 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
814 				  __u64 bytes, __u32 packets)
815 {
816 	bstats->bytes += bytes;
817 	bstats->packets += packets;
818 }
819 
820 static inline void bstats_update(struct gnet_stats_basic_packed *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 _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
829 				      __u64 bytes, __u32 packets)
830 {
831 	u64_stats_update_begin(&bstats->syncp);
832 	_bstats_update(&bstats->bstats, bytes, packets);
833 	u64_stats_update_end(&bstats->syncp);
834 }
835 
836 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
837 				     const struct sk_buff *skb)
838 {
839 	u64_stats_update_begin(&bstats->syncp);
840 	bstats_update(&bstats->bstats, skb);
841 	u64_stats_update_end(&bstats->syncp);
842 }
843 
844 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
845 					   const struct sk_buff *skb)
846 {
847 	bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
848 }
849 
850 static inline void qdisc_bstats_update(struct Qdisc *sch,
851 				       const struct sk_buff *skb)
852 {
853 	bstats_update(&sch->bstats, skb);
854 }
855 
856 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
857 					    const struct sk_buff *skb)
858 {
859 	sch->qstats.backlog -= qdisc_pkt_len(skb);
860 }
861 
862 static inline void qdisc_qstats_cpu_backlog_dec(struct Qdisc *sch,
863 						const struct sk_buff *skb)
864 {
865 	this_cpu_sub(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
866 }
867 
868 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
869 					    const struct sk_buff *skb)
870 {
871 	sch->qstats.backlog += qdisc_pkt_len(skb);
872 }
873 
874 static inline void qdisc_qstats_cpu_backlog_inc(struct Qdisc *sch,
875 						const struct sk_buff *skb)
876 {
877 	this_cpu_add(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
878 }
879 
880 static inline void qdisc_qstats_atomic_qlen_inc(struct Qdisc *sch)
881 {
882 	atomic_inc(&sch->q.atomic_qlen);
883 }
884 
885 static inline void qdisc_qstats_atomic_qlen_dec(struct Qdisc *sch)
886 {
887 	atomic_dec(&sch->q.atomic_qlen);
888 }
889 
890 static inline void qdisc_qstats_cpu_requeues_inc(struct Qdisc *sch)
891 {
892 	this_cpu_inc(sch->cpu_qstats->requeues);
893 }
894 
895 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
896 {
897 	sch->qstats.drops += count;
898 }
899 
900 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
901 {
902 	qstats->drops++;
903 }
904 
905 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
906 {
907 	qstats->overlimits++;
908 }
909 
910 static inline void qdisc_qstats_drop(struct Qdisc *sch)
911 {
912 	qstats_drop_inc(&sch->qstats);
913 }
914 
915 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
916 {
917 	this_cpu_inc(sch->cpu_qstats->drops);
918 }
919 
920 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
921 {
922 	sch->qstats.overlimits++;
923 }
924 
925 static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
926 {
927 	qh->head = NULL;
928 	qh->tail = NULL;
929 	qh->qlen = 0;
930 }
931 
932 static inline void __qdisc_enqueue_tail(struct sk_buff *skb,
933 					struct qdisc_skb_head *qh)
934 {
935 	struct sk_buff *last = qh->tail;
936 
937 	if (last) {
938 		skb->next = NULL;
939 		last->next = skb;
940 		qh->tail = skb;
941 	} else {
942 		qh->tail = skb;
943 		qh->head = skb;
944 	}
945 	qh->qlen++;
946 }
947 
948 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
949 {
950 	__qdisc_enqueue_tail(skb, &sch->q);
951 	qdisc_qstats_backlog_inc(sch, skb);
952 	return NET_XMIT_SUCCESS;
953 }
954 
955 static inline void __qdisc_enqueue_head(struct sk_buff *skb,
956 					struct qdisc_skb_head *qh)
957 {
958 	skb->next = qh->head;
959 
960 	if (!qh->head)
961 		qh->tail = skb;
962 	qh->head = skb;
963 	qh->qlen++;
964 }
965 
966 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
967 {
968 	struct sk_buff *skb = qh->head;
969 
970 	if (likely(skb != NULL)) {
971 		qh->head = skb->next;
972 		qh->qlen--;
973 		if (qh->head == NULL)
974 			qh->tail = NULL;
975 		skb->next = NULL;
976 	}
977 
978 	return skb;
979 }
980 
981 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
982 {
983 	struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
984 
985 	if (likely(skb != NULL)) {
986 		qdisc_qstats_backlog_dec(sch, skb);
987 		qdisc_bstats_update(sch, skb);
988 	}
989 
990 	return skb;
991 }
992 
993 /* Instead of calling kfree_skb() while root qdisc lock is held,
994  * queue the skb for future freeing at end of __dev_xmit_skb()
995  */
996 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
997 {
998 	skb->next = *to_free;
999 	*to_free = skb;
1000 }
1001 
1002 static inline void __qdisc_drop_all(struct sk_buff *skb,
1003 				    struct sk_buff **to_free)
1004 {
1005 	if (skb->prev)
1006 		skb->prev->next = *to_free;
1007 	else
1008 		skb->next = *to_free;
1009 	*to_free = skb;
1010 }
1011 
1012 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
1013 						   struct qdisc_skb_head *qh,
1014 						   struct sk_buff **to_free)
1015 {
1016 	struct sk_buff *skb = __qdisc_dequeue_head(qh);
1017 
1018 	if (likely(skb != NULL)) {
1019 		unsigned int len = qdisc_pkt_len(skb);
1020 
1021 		qdisc_qstats_backlog_dec(sch, skb);
1022 		__qdisc_drop(skb, to_free);
1023 		return len;
1024 	}
1025 
1026 	return 0;
1027 }
1028 
1029 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
1030 						 struct sk_buff **to_free)
1031 {
1032 	return __qdisc_queue_drop_head(sch, &sch->q, to_free);
1033 }
1034 
1035 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
1036 {
1037 	const struct qdisc_skb_head *qh = &sch->q;
1038 
1039 	return qh->head;
1040 }
1041 
1042 /* generic pseudo peek method for non-work-conserving qdisc */
1043 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
1044 {
1045 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
1046 
1047 	/* we can reuse ->gso_skb because peek isn't called for root qdiscs */
1048 	if (!skb) {
1049 		skb = sch->dequeue(sch);
1050 
1051 		if (skb) {
1052 			__skb_queue_head(&sch->gso_skb, skb);
1053 			/* it's still part of the queue */
1054 			qdisc_qstats_backlog_inc(sch, skb);
1055 			sch->q.qlen++;
1056 		}
1057 	}
1058 
1059 	return skb;
1060 }
1061 
1062 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
1063 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
1064 {
1065 	struct sk_buff *skb = skb_peek(&sch->gso_skb);
1066 
1067 	if (skb) {
1068 		skb = __skb_dequeue(&sch->gso_skb);
1069 		qdisc_qstats_backlog_dec(sch, skb);
1070 		sch->q.qlen--;
1071 	} else {
1072 		skb = sch->dequeue(sch);
1073 	}
1074 
1075 	return skb;
1076 }
1077 
1078 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
1079 {
1080 	/*
1081 	 * We do not know the backlog in bytes of this list, it
1082 	 * is up to the caller to correct it
1083 	 */
1084 	ASSERT_RTNL();
1085 	if (qh->qlen) {
1086 		rtnl_kfree_skbs(qh->head, qh->tail);
1087 
1088 		qh->head = NULL;
1089 		qh->tail = NULL;
1090 		qh->qlen = 0;
1091 	}
1092 }
1093 
1094 static inline void qdisc_reset_queue(struct Qdisc *sch)
1095 {
1096 	__qdisc_reset_queue(&sch->q);
1097 	sch->qstats.backlog = 0;
1098 }
1099 
1100 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
1101 					  struct Qdisc **pold)
1102 {
1103 	struct Qdisc *old;
1104 
1105 	sch_tree_lock(sch);
1106 	old = *pold;
1107 	*pold = new;
1108 	if (old != NULL) {
1109 		unsigned int qlen = old->q.qlen;
1110 		unsigned int backlog = old->qstats.backlog;
1111 
1112 		qdisc_reset(old);
1113 		qdisc_tree_reduce_backlog(old, qlen, backlog);
1114 	}
1115 	sch_tree_unlock(sch);
1116 
1117 	return old;
1118 }
1119 
1120 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
1121 {
1122 	rtnl_kfree_skbs(skb, skb);
1123 	qdisc_qstats_drop(sch);
1124 }
1125 
1126 static inline int qdisc_drop_cpu(struct sk_buff *skb, struct Qdisc *sch,
1127 				 struct sk_buff **to_free)
1128 {
1129 	__qdisc_drop(skb, to_free);
1130 	qdisc_qstats_cpu_drop(sch);
1131 
1132 	return NET_XMIT_DROP;
1133 }
1134 
1135 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
1136 			     struct sk_buff **to_free)
1137 {
1138 	__qdisc_drop(skb, to_free);
1139 	qdisc_qstats_drop(sch);
1140 
1141 	return NET_XMIT_DROP;
1142 }
1143 
1144 static inline int qdisc_drop_all(struct sk_buff *skb, struct Qdisc *sch,
1145 				 struct sk_buff **to_free)
1146 {
1147 	__qdisc_drop_all(skb, to_free);
1148 	qdisc_qstats_drop(sch);
1149 
1150 	return NET_XMIT_DROP;
1151 }
1152 
1153 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
1154    long it will take to send a packet given its size.
1155  */
1156 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
1157 {
1158 	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
1159 	if (slot < 0)
1160 		slot = 0;
1161 	slot >>= rtab->rate.cell_log;
1162 	if (slot > 255)
1163 		return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
1164 	return rtab->data[slot];
1165 }
1166 
1167 struct psched_ratecfg {
1168 	u64	rate_bytes_ps; /* bytes per second */
1169 	u32	mult;
1170 	u16	overhead;
1171 	u8	linklayer;
1172 	u8	shift;
1173 };
1174 
1175 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
1176 				unsigned int len)
1177 {
1178 	len += r->overhead;
1179 
1180 	if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
1181 		return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
1182 
1183 	return ((u64)len * r->mult) >> r->shift;
1184 }
1185 
1186 void psched_ratecfg_precompute(struct psched_ratecfg *r,
1187 			       const struct tc_ratespec *conf,
1188 			       u64 rate64);
1189 
1190 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
1191 					  const struct psched_ratecfg *r)
1192 {
1193 	memset(res, 0, sizeof(*res));
1194 
1195 	/* legacy struct tc_ratespec has a 32bit @rate field
1196 	 * Qdisc using 64bit rate should add new attributes
1197 	 * in order to maintain compatibility.
1198 	 */
1199 	res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
1200 
1201 	res->overhead = r->overhead;
1202 	res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
1203 }
1204 
1205 /* Mini Qdisc serves for specific needs of ingress/clsact Qdisc.
1206  * The fast path only needs to access filter list and to update stats
1207  */
1208 struct mini_Qdisc {
1209 	struct tcf_proto *filter_list;
1210 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
1211 	struct gnet_stats_queue	__percpu *cpu_qstats;
1212 	struct rcu_head rcu;
1213 };
1214 
1215 static inline void mini_qdisc_bstats_cpu_update(struct mini_Qdisc *miniq,
1216 						const struct sk_buff *skb)
1217 {
1218 	bstats_cpu_update(this_cpu_ptr(miniq->cpu_bstats), skb);
1219 }
1220 
1221 static inline void mini_qdisc_qstats_cpu_drop(struct mini_Qdisc *miniq)
1222 {
1223 	this_cpu_inc(miniq->cpu_qstats->drops);
1224 }
1225 
1226 struct mini_Qdisc_pair {
1227 	struct mini_Qdisc miniq1;
1228 	struct mini_Qdisc miniq2;
1229 	struct mini_Qdisc __rcu **p_miniq;
1230 };
1231 
1232 void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
1233 			  struct tcf_proto *tp_head);
1234 void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
1235 			  struct mini_Qdisc __rcu **p_miniq);
1236 
1237 static inline void skb_tc_reinsert(struct sk_buff *skb, struct tcf_result *res)
1238 {
1239 	struct gnet_stats_queue *stats = res->qstats;
1240 	int ret;
1241 
1242 	if (res->ingress)
1243 		ret = netif_receive_skb(skb);
1244 	else
1245 		ret = dev_queue_xmit(skb);
1246 	if (ret && stats)
1247 		qstats_overlimit_inc(res->qstats);
1248 }
1249 
1250 #endif
1251