xref: /openbmc/linux/include/net/sch_generic.h (revision 384740dc)
1 #ifndef __NET_SCHED_GENERIC_H
2 #define __NET_SCHED_GENERIC_H
3 
4 #include <linux/netdevice.h>
5 #include <linux/types.h>
6 #include <linux/rcupdate.h>
7 #include <linux/module.h>
8 #include <linux/pkt_sched.h>
9 #include <linux/pkt_cls.h>
10 #include <net/gen_stats.h>
11 #include <net/rtnetlink.h>
12 
13 struct Qdisc_ops;
14 struct qdisc_walker;
15 struct tcf_walker;
16 struct module;
17 
18 struct qdisc_rate_table
19 {
20 	struct tc_ratespec rate;
21 	u32		data[256];
22 	struct qdisc_rate_table *next;
23 	int		refcnt;
24 };
25 
26 enum qdisc_state_t
27 {
28 	__QDISC_STATE_RUNNING,
29 	__QDISC_STATE_SCHED,
30 	__QDISC_STATE_DEACTIVATED,
31 };
32 
33 struct qdisc_size_table {
34 	struct list_head	list;
35 	struct tc_sizespec	szopts;
36 	int			refcnt;
37 	u16			data[];
38 };
39 
40 struct Qdisc
41 {
42 	int 			(*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
43 	struct sk_buff *	(*dequeue)(struct Qdisc *dev);
44 	unsigned		flags;
45 #define TCQ_F_BUILTIN	1
46 #define TCQ_F_THROTTLED	2
47 #define TCQ_F_INGRESS	4
48 	int			padded;
49 	struct Qdisc_ops	*ops;
50 	struct qdisc_size_table	*stab;
51 	u32			handle;
52 	u32			parent;
53 	atomic_t		refcnt;
54 	unsigned long		state;
55 	struct sk_buff		*gso_skb;
56 	struct sk_buff_head	q;
57 	struct netdev_queue	*dev_queue;
58 	struct Qdisc		*next_sched;
59 	struct list_head	list;
60 
61 	struct gnet_stats_basic	bstats;
62 	struct gnet_stats_queue	qstats;
63 	struct gnet_stats_rate_est	rate_est;
64 	int			(*reshape_fail)(struct sk_buff *skb,
65 					struct Qdisc *q);
66 
67 	void			*u32_node;
68 
69 	/* This field is deprecated, but it is still used by CBQ
70 	 * and it will live until better solution will be invented.
71 	 */
72 	struct Qdisc		*__parent;
73 };
74 
75 struct Qdisc_class_ops
76 {
77 	/* Child qdisc manipulation */
78 	int			(*graft)(struct Qdisc *, unsigned long cl,
79 					struct Qdisc *, struct Qdisc **);
80 	struct Qdisc *		(*leaf)(struct Qdisc *, unsigned long cl);
81 	void			(*qlen_notify)(struct Qdisc *, unsigned long);
82 
83 	/* Class manipulation routines */
84 	unsigned long		(*get)(struct Qdisc *, u32 classid);
85 	void			(*put)(struct Qdisc *, unsigned long);
86 	int			(*change)(struct Qdisc *, u32, u32,
87 					struct nlattr **, unsigned long *);
88 	int			(*delete)(struct Qdisc *, unsigned long);
89 	void			(*walk)(struct Qdisc *, struct qdisc_walker * arg);
90 
91 	/* Filter manipulation */
92 	struct tcf_proto **	(*tcf_chain)(struct Qdisc *, unsigned long);
93 	unsigned long		(*bind_tcf)(struct Qdisc *, unsigned long,
94 					u32 classid);
95 	void			(*unbind_tcf)(struct Qdisc *, unsigned long);
96 
97 	/* rtnetlink specific */
98 	int			(*dump)(struct Qdisc *, unsigned long,
99 					struct sk_buff *skb, struct tcmsg*);
100 	int			(*dump_stats)(struct Qdisc *, unsigned long,
101 					struct gnet_dump *);
102 };
103 
104 struct Qdisc_ops
105 {
106 	struct Qdisc_ops	*next;
107 	const struct Qdisc_class_ops	*cl_ops;
108 	char			id[IFNAMSIZ];
109 	int			priv_size;
110 
111 	int 			(*enqueue)(struct sk_buff *, struct Qdisc *);
112 	struct sk_buff *	(*dequeue)(struct Qdisc *);
113 	int 			(*requeue)(struct sk_buff *, struct Qdisc *);
114 	unsigned int		(*drop)(struct Qdisc *);
115 
116 	int			(*init)(struct Qdisc *, struct nlattr *arg);
117 	void			(*reset)(struct Qdisc *);
118 	void			(*destroy)(struct Qdisc *);
119 	int			(*change)(struct Qdisc *, struct nlattr *arg);
120 
121 	int			(*dump)(struct Qdisc *, struct sk_buff *);
122 	int			(*dump_stats)(struct Qdisc *, struct gnet_dump *);
123 
124 	struct module		*owner;
125 };
126 
127 
128 struct tcf_result
129 {
130 	unsigned long	class;
131 	u32		classid;
132 };
133 
134 struct tcf_proto_ops
135 {
136 	struct tcf_proto_ops	*next;
137 	char			kind[IFNAMSIZ];
138 
139 	int			(*classify)(struct sk_buff*, struct tcf_proto*,
140 					struct tcf_result *);
141 	int			(*init)(struct tcf_proto*);
142 	void			(*destroy)(struct tcf_proto*);
143 
144 	unsigned long		(*get)(struct tcf_proto*, u32 handle);
145 	void			(*put)(struct tcf_proto*, unsigned long);
146 	int			(*change)(struct tcf_proto*, unsigned long,
147 					u32 handle, struct nlattr **,
148 					unsigned long *);
149 	int			(*delete)(struct tcf_proto*, unsigned long);
150 	void			(*walk)(struct tcf_proto*, struct tcf_walker *arg);
151 
152 	/* rtnetlink specific */
153 	int			(*dump)(struct tcf_proto*, unsigned long,
154 					struct sk_buff *skb, struct tcmsg*);
155 
156 	struct module		*owner;
157 };
158 
159 struct tcf_proto
160 {
161 	/* Fast access part */
162 	struct tcf_proto	*next;
163 	void			*root;
164 	int			(*classify)(struct sk_buff*, struct tcf_proto*,
165 					struct tcf_result *);
166 	__be16			protocol;
167 
168 	/* All the rest */
169 	u32			prio;
170 	u32			classid;
171 	struct Qdisc		*q;
172 	void			*data;
173 	struct tcf_proto_ops	*ops;
174 };
175 
176 struct qdisc_skb_cb {
177 	unsigned int		pkt_len;
178 	char			data[];
179 };
180 
181 static inline struct qdisc_skb_cb *qdisc_skb_cb(struct sk_buff *skb)
182 {
183 	return (struct qdisc_skb_cb *)skb->cb;
184 }
185 
186 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
187 {
188 	return &qdisc->q.lock;
189 }
190 
191 static inline struct Qdisc *qdisc_root(struct Qdisc *qdisc)
192 {
193 	return qdisc->dev_queue->qdisc;
194 }
195 
196 static inline struct Qdisc *qdisc_root_sleeping(struct Qdisc *qdisc)
197 {
198 	return qdisc->dev_queue->qdisc_sleeping;
199 }
200 
201 /* The qdisc root lock is a mechanism by which to top level
202  * of a qdisc tree can be locked from any qdisc node in the
203  * forest.  This allows changing the configuration of some
204  * aspect of the qdisc tree while blocking out asynchronous
205  * qdisc access in the packet processing paths.
206  *
207  * It is only legal to do this when the root will not change
208  * on us.  Otherwise we'll potentially lock the wrong qdisc
209  * root.  This is enforced by holding the RTNL semaphore, which
210  * all users of this lock accessor must do.
211  */
212 static inline spinlock_t *qdisc_root_lock(struct Qdisc *qdisc)
213 {
214 	struct Qdisc *root = qdisc_root(qdisc);
215 
216 	ASSERT_RTNL();
217 	return qdisc_lock(root);
218 }
219 
220 static inline spinlock_t *qdisc_root_sleeping_lock(struct Qdisc *qdisc)
221 {
222 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
223 
224 	ASSERT_RTNL();
225 	return qdisc_lock(root);
226 }
227 
228 static inline struct net_device *qdisc_dev(struct Qdisc *qdisc)
229 {
230 	return qdisc->dev_queue->dev;
231 }
232 
233 static inline void sch_tree_lock(struct Qdisc *q)
234 {
235 	spin_lock_bh(qdisc_root_sleeping_lock(q));
236 }
237 
238 static inline void sch_tree_unlock(struct Qdisc *q)
239 {
240 	spin_unlock_bh(qdisc_root_sleeping_lock(q));
241 }
242 
243 #define tcf_tree_lock(tp)	sch_tree_lock((tp)->q)
244 #define tcf_tree_unlock(tp)	sch_tree_unlock((tp)->q)
245 
246 extern struct Qdisc noop_qdisc;
247 extern struct Qdisc_ops noop_qdisc_ops;
248 
249 struct Qdisc_class_common
250 {
251 	u32			classid;
252 	struct hlist_node	hnode;
253 };
254 
255 struct Qdisc_class_hash
256 {
257 	struct hlist_head	*hash;
258 	unsigned int		hashsize;
259 	unsigned int		hashmask;
260 	unsigned int		hashelems;
261 };
262 
263 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
264 {
265 	id ^= id >> 8;
266 	id ^= id >> 4;
267 	return id & mask;
268 }
269 
270 static inline struct Qdisc_class_common *
271 qdisc_class_find(struct Qdisc_class_hash *hash, u32 id)
272 {
273 	struct Qdisc_class_common *cl;
274 	struct hlist_node *n;
275 	unsigned int h;
276 
277 	h = qdisc_class_hash(id, hash->hashmask);
278 	hlist_for_each_entry(cl, n, &hash->hash[h], hnode) {
279 		if (cl->classid == id)
280 			return cl;
281 	}
282 	return NULL;
283 }
284 
285 extern int qdisc_class_hash_init(struct Qdisc_class_hash *);
286 extern void qdisc_class_hash_insert(struct Qdisc_class_hash *, struct Qdisc_class_common *);
287 extern void qdisc_class_hash_remove(struct Qdisc_class_hash *, struct Qdisc_class_common *);
288 extern void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
289 extern void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
290 
291 extern void dev_init_scheduler(struct net_device *dev);
292 extern void dev_shutdown(struct net_device *dev);
293 extern void dev_activate(struct net_device *dev);
294 extern void dev_deactivate(struct net_device *dev);
295 extern void qdisc_reset(struct Qdisc *qdisc);
296 extern void qdisc_destroy(struct Qdisc *qdisc);
297 extern void qdisc_tree_decrease_qlen(struct Qdisc *qdisc, unsigned int n);
298 extern struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
299 				 struct Qdisc_ops *ops);
300 extern struct Qdisc *qdisc_create_dflt(struct net_device *dev,
301 				       struct netdev_queue *dev_queue,
302 				       struct Qdisc_ops *ops, u32 parentid);
303 extern void qdisc_calculate_pkt_len(struct sk_buff *skb,
304 				   struct qdisc_size_table *stab);
305 extern void tcf_destroy(struct tcf_proto *tp);
306 extern void tcf_destroy_chain(struct tcf_proto **fl);
307 
308 /* Reset all TX qdiscs of a device.  */
309 static inline void qdisc_reset_all_tx(struct net_device *dev)
310 {
311 	unsigned int i;
312 	for (i = 0; i < dev->num_tx_queues; i++)
313 		qdisc_reset(netdev_get_tx_queue(dev, i)->qdisc);
314 }
315 
316 /* Are all TX queues of the device empty?  */
317 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
318 {
319 	unsigned int i;
320 	for (i = 0; i < dev->num_tx_queues; i++) {
321 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
322 		const struct Qdisc *q = txq->qdisc;
323 
324 		if (q->q.qlen)
325 			return false;
326 	}
327 	return true;
328 }
329 
330 /* Are any of the TX qdiscs changing?  */
331 static inline bool qdisc_tx_changing(struct net_device *dev)
332 {
333 	unsigned int i;
334 	for (i = 0; i < dev->num_tx_queues; i++) {
335 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
336 		if (txq->qdisc != txq->qdisc_sleeping)
337 			return true;
338 	}
339 	return false;
340 }
341 
342 /* Is the device using the noop qdisc on all queues?  */
343 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
344 {
345 	unsigned int i;
346 	for (i = 0; i < dev->num_tx_queues; i++) {
347 		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
348 		if (txq->qdisc != &noop_qdisc)
349 			return false;
350 	}
351 	return true;
352 }
353 
354 static inline unsigned int qdisc_pkt_len(struct sk_buff *skb)
355 {
356 	return qdisc_skb_cb(skb)->pkt_len;
357 }
358 
359 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
360 enum net_xmit_qdisc_t {
361 	__NET_XMIT_STOLEN = 0x00010000,
362 	__NET_XMIT_BYPASS = 0x00020000,
363 };
364 
365 #ifdef CONFIG_NET_CLS_ACT
366 #define net_xmit_drop_count(e)	((e) & __NET_XMIT_STOLEN ? 0 : 1)
367 #else
368 #define net_xmit_drop_count(e)	(1)
369 #endif
370 
371 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
372 {
373 #ifdef CONFIG_NET_SCHED
374 	if (sch->stab)
375 		qdisc_calculate_pkt_len(skb, sch->stab);
376 #endif
377 	return sch->enqueue(skb, sch);
378 }
379 
380 static inline int qdisc_enqueue_root(struct sk_buff *skb, struct Qdisc *sch)
381 {
382 	qdisc_skb_cb(skb)->pkt_len = skb->len;
383 	return qdisc_enqueue(skb, sch) & NET_XMIT_MASK;
384 }
385 
386 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
387 				       struct sk_buff_head *list)
388 {
389 	__skb_queue_tail(list, skb);
390 	sch->qstats.backlog += qdisc_pkt_len(skb);
391 	sch->bstats.bytes += qdisc_pkt_len(skb);
392 	sch->bstats.packets++;
393 
394 	return NET_XMIT_SUCCESS;
395 }
396 
397 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
398 {
399 	return __qdisc_enqueue_tail(skb, sch, &sch->q);
400 }
401 
402 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch,
403 						   struct sk_buff_head *list)
404 {
405 	struct sk_buff *skb = __skb_dequeue(list);
406 
407 	if (likely(skb != NULL))
408 		sch->qstats.backlog -= qdisc_pkt_len(skb);
409 
410 	return skb;
411 }
412 
413 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
414 {
415 	return __qdisc_dequeue_head(sch, &sch->q);
416 }
417 
418 static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch,
419 						   struct sk_buff_head *list)
420 {
421 	struct sk_buff *skb = __skb_dequeue_tail(list);
422 
423 	if (likely(skb != NULL))
424 		sch->qstats.backlog -= qdisc_pkt_len(skb);
425 
426 	return skb;
427 }
428 
429 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
430 {
431 	return __qdisc_dequeue_tail(sch, &sch->q);
432 }
433 
434 static inline int __qdisc_requeue(struct sk_buff *skb, struct Qdisc *sch,
435 				  struct sk_buff_head *list)
436 {
437 	__skb_queue_head(list, skb);
438 	sch->qstats.backlog += qdisc_pkt_len(skb);
439 	sch->qstats.requeues++;
440 
441 	return NET_XMIT_SUCCESS;
442 }
443 
444 static inline int qdisc_requeue(struct sk_buff *skb, struct Qdisc *sch)
445 {
446 	return __qdisc_requeue(skb, sch, &sch->q);
447 }
448 
449 static inline void __qdisc_reset_queue(struct Qdisc *sch,
450 				       struct sk_buff_head *list)
451 {
452 	/*
453 	 * We do not know the backlog in bytes of this list, it
454 	 * is up to the caller to correct it
455 	 */
456 	__skb_queue_purge(list);
457 }
458 
459 static inline void qdisc_reset_queue(struct Qdisc *sch)
460 {
461 	__qdisc_reset_queue(sch, &sch->q);
462 	sch->qstats.backlog = 0;
463 }
464 
465 static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch,
466 					      struct sk_buff_head *list)
467 {
468 	struct sk_buff *skb = __qdisc_dequeue_tail(sch, list);
469 
470 	if (likely(skb != NULL)) {
471 		unsigned int len = qdisc_pkt_len(skb);
472 		kfree_skb(skb);
473 		return len;
474 	}
475 
476 	return 0;
477 }
478 
479 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch)
480 {
481 	return __qdisc_queue_drop(sch, &sch->q);
482 }
483 
484 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
485 {
486 	kfree_skb(skb);
487 	sch->qstats.drops++;
488 
489 	return NET_XMIT_DROP;
490 }
491 
492 static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch)
493 {
494 	sch->qstats.drops++;
495 
496 #ifdef CONFIG_NET_CLS_ACT
497 	if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch))
498 		goto drop;
499 
500 	return NET_XMIT_SUCCESS;
501 
502 drop:
503 #endif
504 	kfree_skb(skb);
505 	return NET_XMIT_DROP;
506 }
507 
508 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
509    long it will take to send a packet given its size.
510  */
511 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
512 {
513 	int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
514 	if (slot < 0)
515 		slot = 0;
516 	slot >>= rtab->rate.cell_log;
517 	if (slot > 255)
518 		return (rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF]);
519 	return rtab->data[slot];
520 }
521 
522 #ifdef CONFIG_NET_CLS_ACT
523 static inline struct sk_buff *skb_act_clone(struct sk_buff *skb, gfp_t gfp_mask)
524 {
525 	struct sk_buff *n = skb_clone(skb, gfp_mask);
526 
527 	if (n) {
528 		n->tc_verd = SET_TC_VERD(n->tc_verd, 0);
529 		n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);
530 		n->tc_verd = CLR_TC_MUNGED(n->tc_verd);
531 	}
532 	return n;
533 }
534 #endif
535 
536 #endif
537