]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - include/net/sch_generic.h
projects / mirror_ubuntu-artful-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
UBUNTU: [Config] CONFIG_MFD_TI_LMU=m
[mirror_ubuntu-artful-kernel.git] / include / net / sch_generic.h
1 #ifndef __NET_SCHED_GENERIC_H
2 #define __NET_SCHED_GENERIC_H
3
4 #include <linux/netdevice.h>
5 #include <linux/types.h>
6 #include <linux/rcupdate.h>
7 #include <linux/pkt_sched.h>
8 #include <linux/pkt_cls.h>
9 #include <linux/percpu.h>
10 #include <linux/dynamic_queue_limits.h>
11 #include <linux/list.h>
12 #include <linux/refcount.h>
13 #include <net/gen_stats.h>
14 #include <net/rtnetlink.h>
15
16 struct Qdisc_ops;
17 struct qdisc_walker;
18 struct tcf_walker;
19 struct module;
20
21 struct qdisc_rate_table {
22 struct tc_ratespec rate;
23 u32 data[256];
24 struct qdisc_rate_table *next;
25 int refcnt;
26 };
27
28 enum qdisc_state_t {
29 __QDISC_STATE_SCHED,
30 __QDISC_STATE_DEACTIVATED,
31 };
32
33 struct qdisc_size_table {
34 struct rcu_head rcu;
35 struct list_head list;
36 struct tc_sizespec szopts;
37 int refcnt;
38 u16 data[];
39 };
40
41 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
42 struct qdisc_skb_head {
43 struct sk_buff *head;
44 struct sk_buff *tail;
45 __u32 qlen;
46 spinlock_t lock;
47 };
48
49 struct Qdisc {
50 int (*enqueue)(struct sk_buff *skb,
51 struct Qdisc *sch,
52 struct sk_buff **to_free);
53 struct sk_buff * (*dequeue)(struct Qdisc *sch);
54 unsigned int flags;
55 #define TCQ_F_BUILTIN 1
56 #define TCQ_F_INGRESS 2
57 #define TCQ_F_CAN_BYPASS 4
58 #define TCQ_F_MQROOT 8
59 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
60 * q->dev_queue : It can test
61 * netif_xmit_frozen_or_stopped() before
62 * dequeueing next packet.
63 * Its true for MQ/MQPRIO slaves, or non
64 * multiqueue device.
65 */
66 #define TCQ_F_WARN_NONWC (1 << 16)
67 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
68 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
69 * qdisc_tree_decrease_qlen() should stop.
70 */
71 #define TCQ_F_INVISIBLE 0x80 /* invisible by default in dump */
72 u32 limit;
73 const struct Qdisc_ops *ops;
74 struct qdisc_size_table __rcu *stab;
75 struct hlist_node hash;
76 u32 handle;
77 u32 parent;
78 void *u32_node;
79
80 struct netdev_queue *dev_queue;
81
82 struct net_rate_estimator __rcu *rate_est;
83 struct gnet_stats_basic_cpu __percpu *cpu_bstats;
84 struct gnet_stats_queue __percpu *cpu_qstats;
85
86 /*
87 * For performance sake on SMP, we put highly modified fields at the end
88 */
89 struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
90 struct qdisc_skb_head q;
91 struct gnet_stats_basic_packed bstats;
92 seqcount_t running;
93 struct gnet_stats_queue qstats;
94 unsigned long state;
95 struct Qdisc *next_sched;
96 struct sk_buff *skb_bad_txq;
97 struct rcu_head rcu_head;
98 int padded;
99 refcount_t refcnt;
100
101 spinlock_t busylock ____cacheline_aligned_in_smp;
102 };
103
104 static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
105 {
106 if (qdisc->flags & TCQ_F_BUILTIN)
107 return;
108 refcount_inc(&qdisc->refcnt);
109 }
110
111 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
112 {
113 return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
114 }
115
116 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
117 {
118 if (qdisc_is_running(qdisc))
119 return false;
120 /* Variant of write_seqcount_begin() telling lockdep a trylock
121 * was attempted.
122 */
123 raw_write_seqcount_begin(&qdisc->running);
124 seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
125 return true;
126 }
127
128 static inline void qdisc_run_end(struct Qdisc *qdisc)
129 {
130 write_seqcount_end(&qdisc->running);
131 }
132
133 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
134 {
135 return qdisc->flags & TCQ_F_ONETXQUEUE;
136 }
137
138 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
139 {
140 #ifdef CONFIG_BQL
141 /* Non-BQL migrated drivers will return 0, too. */
142 return dql_avail(&txq->dql);
143 #else
144 return 0;
145 #endif
146 }
147
148 struct Qdisc_class_ops {
149 /* Child qdisc manipulation */
150 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
151 int (*graft)(struct Qdisc *, unsigned long cl,
152 struct Qdisc *, struct Qdisc **);
153 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
154 void (*qlen_notify)(struct Qdisc *, unsigned long);
155
156 /* Class manipulation routines */
157 unsigned long (*get)(struct Qdisc *, u32 classid);
158 void (*put)(struct Qdisc *, unsigned long);
159 int (*change)(struct Qdisc *, u32, u32,
160 struct nlattr **, unsigned long *);
161 int (*delete)(struct Qdisc *, unsigned long);
162 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
163
164 /* Filter manipulation */
165 struct tcf_block * (*tcf_block)(struct Qdisc *, unsigned long);
166 bool (*tcf_cl_offload)(u32 classid);
167 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
168 u32 classid);
169 void (*unbind_tcf)(struct Qdisc *, unsigned long);
170
171 /* rtnetlink specific */
172 int (*dump)(struct Qdisc *, unsigned long,
173 struct sk_buff *skb, struct tcmsg*);
174 int (*dump_stats)(struct Qdisc *, unsigned long,
175 struct gnet_dump *);
176 };
177
178 struct Qdisc_ops {
179 struct Qdisc_ops *next;
180 const struct Qdisc_class_ops *cl_ops;
181 char id[IFNAMSIZ];
182 int priv_size;
183
184 int (*enqueue)(struct sk_buff *skb,
185 struct Qdisc *sch,
186 struct sk_buff **to_free);
187 struct sk_buff * (*dequeue)(struct Qdisc *);
188 struct sk_buff * (*peek)(struct Qdisc *);
189
190 int (*init)(struct Qdisc *, struct nlattr *arg);
191 void (*reset)(struct Qdisc *);
192 void (*destroy)(struct Qdisc *);
193 int (*change)(struct Qdisc *, struct nlattr *arg);
194 void (*attach)(struct Qdisc *);
195
196 int (*dump)(struct Qdisc *, struct sk_buff *);
197 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
198
199 struct module *owner;
200 };
201
202
203 struct tcf_result {
204 union {
205 struct {
206 unsigned long class;
207 u32 classid;
208 };
209 const struct tcf_proto *goto_tp;
210 };
211 };
212
213 struct tcf_proto_ops {
214 struct list_head head;
215 char kind[IFNAMSIZ];
216
217 int (*classify)(struct sk_buff *,
218 const struct tcf_proto *,
219 struct tcf_result *);
220 int (*init)(struct tcf_proto*);
221 void (*destroy)(struct tcf_proto*);
222
223 unsigned long (*get)(struct tcf_proto*, u32 handle);
224 int (*change)(struct net *net, struct sk_buff *,
225 struct tcf_proto*, unsigned long,
226 u32 handle, struct nlattr **,
227 unsigned long *, bool);
228 int (*delete)(struct tcf_proto*, unsigned long, bool*);
229 void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
230
231 /* rtnetlink specific */
232 int (*dump)(struct net*, struct tcf_proto*, unsigned long,
233 struct sk_buff *skb, struct tcmsg*);
234
235 struct module *owner;
236 };
237
238 struct tcf_proto {
239 /* Fast access part */
240 struct tcf_proto __rcu *next;
241 void __rcu *root;
242 int (*classify)(struct sk_buff *,
243 const struct tcf_proto *,
244 struct tcf_result *);
245 __be16 protocol;
246
247 /* All the rest */
248 u32 prio;
249 u32 classid;
250 struct Qdisc *q;
251 void *data;
252 const struct tcf_proto_ops *ops;
253 struct tcf_chain *chain;
254 struct rcu_head rcu;
255 };
256
257 struct qdisc_skb_cb {
258 unsigned int pkt_len;
259 u16 slave_dev_queue_mapping;
260 u16 tc_classid;
261 #define QDISC_CB_PRIV_LEN 20
262 unsigned char data[QDISC_CB_PRIV_LEN];
263 };
264
265 struct tcf_chain {
266 struct tcf_proto __rcu *filter_chain;
267 struct tcf_proto __rcu **p_filter_chain;
268 struct list_head list;
269 struct tcf_block *block;
270 u32 index; /* chain index */
271 unsigned int refcnt;
272 };
273
274 struct tcf_block {
275 struct list_head chain_list;
276 };
277
278 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
279 {
280 struct qdisc_skb_cb *qcb;
281
282 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
283 BUILD_BUG_ON(sizeof(qcb->data) < sz);
284 }
285
286 static inline int qdisc_qlen(const struct Qdisc *q)
287 {
288 return q->q.qlen;
289 }
290
291 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
292 {
293 return (struct qdisc_skb_cb *)skb->cb;
294 }
295
296 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
297 {
298 return &qdisc->q.lock;
299 }
300
301 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
302 {
303 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
304
305 return q;
306 }
307
308 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
309 {
310 return qdisc->dev_queue->qdisc_sleeping;
311 }
312
313 /* The qdisc root lock is a mechanism by which to top level
314 * of a qdisc tree can be locked from any qdisc node in the
315 * forest. This allows changing the configuration of some
316 * aspect of the qdisc tree while blocking out asynchronous
317 * qdisc access in the packet processing paths.
318 *
319 * It is only legal to do this when the root will not change
320 * on us. Otherwise we'll potentially lock the wrong qdisc
321 * root. This is enforced by holding the RTNL semaphore, which
322 * all users of this lock accessor must do.
323 */
324 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
325 {
326 struct Qdisc *root = qdisc_root(qdisc);
327
328 ASSERT_RTNL();
329 return qdisc_lock(root);
330 }
331
332 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
333 {
334 struct Qdisc *root = qdisc_root_sleeping(qdisc);
335
336 ASSERT_RTNL();
337 return qdisc_lock(root);
338 }
339
340 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
341 {
342 struct Qdisc *root = qdisc_root_sleeping(qdisc);
343
344 ASSERT_RTNL();
345 return &root->running;
346 }
347
348 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
349 {
350 return qdisc->dev_queue->dev;
351 }
352
353 static inline void sch_tree_lock(const struct Qdisc *q)
354 {
355 spin_lock_bh(qdisc_root_sleeping_lock(q));
356 }
357
358 static inline void sch_tree_unlock(const struct Qdisc *q)
359 {
360 spin_unlock_bh(qdisc_root_sleeping_lock(q));
361 }
362
363 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
364 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
365
366 extern struct Qdisc noop_qdisc;
367 extern struct Qdisc_ops noop_qdisc_ops;
368 extern struct Qdisc_ops pfifo_fast_ops;
369 extern struct Qdisc_ops mq_qdisc_ops;
370 extern struct Qdisc_ops noqueue_qdisc_ops;
371 extern const struct Qdisc_ops *default_qdisc_ops;
372 static inline const struct Qdisc_ops *
373 get_default_qdisc_ops(const struct net_device *dev, int ntx)
374 {
375 return ntx < dev->real_num_tx_queues ?
376 default_qdisc_ops : &pfifo_fast_ops;
377 }
378
379 struct Qdisc_class_common {
380 u32 classid;
381 struct hlist_node hnode;
382 };
383
384 struct Qdisc_class_hash {
385 struct hlist_head *hash;
386 unsigned int hashsize;
387 unsigned int hashmask;
388 unsigned int hashelems;
389 };
390
391 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
392 {
393 id ^= id >> 8;
394 id ^= id >> 4;
395 return id & mask;
396 }
397
398 static inline struct Qdisc_class_common *
399 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
400 {
401 struct Qdisc_class_common *cl;
402 unsigned int h;
403
404 h = qdisc_class_hash(id, hash->hashmask);
405 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
406 if (cl->classid == id)
407 return cl;
408 }
409 return NULL;
410 }
411
412 int qdisc_class_hash_init(struct Qdisc_class_hash *);
413 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
414 struct Qdisc_class_common *);
415 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
416 struct Qdisc_class_common *);
417 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
418 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
419
420 void dev_init_scheduler(struct net_device *dev);
421 void dev_shutdown(struct net_device *dev);
422 void dev_activate(struct net_device *dev);
423 void dev_deactivate(struct net_device *dev);
424 void dev_deactivate_many(struct list_head *head);
425 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
426 struct Qdisc *qdisc);
427 void qdisc_reset(struct Qdisc *qdisc);
428 void qdisc_destroy(struct Qdisc *qdisc);
429 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
430 unsigned int len);
431 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
432 const struct Qdisc_ops *ops);
433 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
434 const struct Qdisc_ops *ops, u32 parentid);
435 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
436 const struct qdisc_size_table *stab);
437 int skb_do_redirect(struct sk_buff *);
438
439 static inline void skb_reset_tc(struct sk_buff *skb)
440 {
441 #ifdef CONFIG_NET_CLS_ACT
442 skb->tc_redirected = 0;
443 #endif
444 }
445
446 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
447 {
448 #ifdef CONFIG_NET_CLS_ACT
449 return skb->tc_at_ingress;
450 #else
451 return false;
452 #endif
453 }
454
455 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
456 {
457 #ifdef CONFIG_NET_CLS_ACT
458 if (skb->tc_skip_classify) {
459 skb->tc_skip_classify = 0;
460 return true;
461 }
462 #endif
463 return false;
464 }
465
466 /* Reset all TX qdiscs greater then index of a device. */
467 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
468 {
469 struct Qdisc *qdisc;
470
471 for (; i < dev->num_tx_queues; i++) {
472 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
473 if (qdisc) {
474 spin_lock_bh(qdisc_lock(qdisc));
475 qdisc_reset(qdisc);
476 spin_unlock_bh(qdisc_lock(qdisc));
477 }
478 }
479 }
480
481 static inline void qdisc_reset_all_tx(struct net_device *dev)
482 {
483 qdisc_reset_all_tx_gt(dev, 0);
484 }
485
486 /* Are all TX queues of the device empty? */
487 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
488 {
489 unsigned int i;
490
491 rcu_read_lock();
492 for (i = 0; i < dev->num_tx_queues; i++) {
493 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
494 const struct Qdisc *q = rcu_dereference(txq->qdisc);
495
496 if (q->q.qlen) {
497 rcu_read_unlock();
498 return false;
499 }
500 }
501 rcu_read_unlock();
502 return true;
503 }
504
505 /* Are any of the TX qdiscs changing? */
506 static inline bool qdisc_tx_changing(const struct net_device *dev)
507 {
508 unsigned int i;
509
510 for (i = 0; i < dev->num_tx_queues; i++) {
511 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
512 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
513 return true;
514 }
515 return false;
516 }
517
518 /* Is the device using the noop qdisc on all queues? */
519 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
520 {
521 unsigned int i;
522
523 for (i = 0; i < dev->num_tx_queues; i++) {
524 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
525 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
526 return false;
527 }
528 return true;
529 }
530
531 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
532 {
533 return qdisc_skb_cb(skb)->pkt_len;
534 }
535
536 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
537 enum net_xmit_qdisc_t {
538 __NET_XMIT_STOLEN = 0x00010000,
539 __NET_XMIT_BYPASS = 0x00020000,
540 };
541
542 #ifdef CONFIG_NET_CLS_ACT
543 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
544 #else
545 #define net_xmit_drop_count(e) (1)
546 #endif
547
548 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
549 const struct Qdisc *sch)
550 {
551 #ifdef CONFIG_NET_SCHED
552 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
553
554 if (stab)
555 __qdisc_calculate_pkt_len(skb, stab);
556 #endif
557 }
558
559 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
560 struct sk_buff **to_free)
561 {
562 qdisc_calculate_pkt_len(skb, sch);
563 return sch->enqueue(skb, sch, to_free);
564 }
565
566 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
567 {
568 return q->flags & TCQ_F_CPUSTATS;
569 }
570
571 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
572 __u64 bytes, __u32 packets)
573 {
574 bstats->bytes += bytes;
575 bstats->packets += packets;
576 }
577
578 static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
579 const struct sk_buff *skb)
580 {
581 _bstats_update(bstats,
582 qdisc_pkt_len(skb),
583 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
584 }
585
586 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
587 __u64 bytes, __u32 packets)
588 {
589 u64_stats_update_begin(&bstats->syncp);
590 _bstats_update(&bstats->bstats, bytes, packets);
591 u64_stats_update_end(&bstats->syncp);
592 }
593
594 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
595 const struct sk_buff *skb)
596 {
597 u64_stats_update_begin(&bstats->syncp);
598 bstats_update(&bstats->bstats, skb);
599 u64_stats_update_end(&bstats->syncp);
600 }
601
602 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
603 const struct sk_buff *skb)
604 {
605 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
606 }
607
608 static inline void qdisc_bstats_update(struct Qdisc *sch,
609 const struct sk_buff *skb)
610 {
611 bstats_update(&sch->bstats, skb);
612 }
613
614 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
615 const struct sk_buff *skb)
616 {
617 sch->qstats.backlog -= qdisc_pkt_len(skb);
618 }
619
620 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
621 const struct sk_buff *skb)
622 {
623 sch->qstats.backlog += qdisc_pkt_len(skb);
624 }
625
626 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
627 {
628 sch->qstats.drops += count;
629 }
630
631 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
632 {
633 qstats->drops++;
634 }
635
636 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
637 {
638 qstats->overlimits++;
639 }
640
641 static inline void qdisc_qstats_drop(struct Qdisc *sch)
642 {
643 qstats_drop_inc(&sch->qstats);
644 }
645
646 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
647 {
648 this_cpu_inc(sch->cpu_qstats->drops);
649 }
650
651 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
652 {
653 sch->qstats.overlimits++;
654 }
655
656 static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
657 {
658 qh->head = NULL;
659 qh->tail = NULL;
660 qh->qlen = 0;
661 }
662
663 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
664 struct qdisc_skb_head *qh)
665 {
666 struct sk_buff *last = qh->tail;
667
668 if (last) {
669 skb->next = NULL;
670 last->next = skb;
671 qh->tail = skb;
672 } else {
673 qh->tail = skb;
674 qh->head = skb;
675 }
676 qh->qlen++;
677 qdisc_qstats_backlog_inc(sch, skb);
678
679 return NET_XMIT_SUCCESS;
680 }
681
682 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
683 {
684 return __qdisc_enqueue_tail(skb, sch, &sch->q);
685 }
686
687 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
688 {
689 struct sk_buff *skb = qh->head;
690
691 if (likely(skb != NULL)) {
692 qh->head = skb->next;
693 qh->qlen--;
694 if (qh->head == NULL)
695 qh->tail = NULL;
696 skb->next = NULL;
697 }
698
699 return skb;
700 }
701
702 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
703 {
704 struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
705
706 if (likely(skb != NULL)) {
707 qdisc_qstats_backlog_dec(sch, skb);
708 qdisc_bstats_update(sch, skb);
709 }
710
711 return skb;
712 }
713
714 /* Instead of calling kfree_skb() while root qdisc lock is held,
715 * queue the skb for future freeing at end of __dev_xmit_skb()
716 */
717 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
718 {
719 skb->next = *to_free;
720 *to_free = skb;
721 }
722
723 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
724 struct qdisc_skb_head *qh,
725 struct sk_buff **to_free)
726 {
727 struct sk_buff *skb = __qdisc_dequeue_head(qh);
728
729 if (likely(skb != NULL)) {
730 unsigned int len = qdisc_pkt_len(skb);
731
732 qdisc_qstats_backlog_dec(sch, skb);
733 __qdisc_drop(skb, to_free);
734 return len;
735 }
736
737 return 0;
738 }
739
740 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
741 struct sk_buff **to_free)
742 {
743 return __qdisc_queue_drop_head(sch, &sch->q, to_free);
744 }
745
746 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
747 {
748 const struct qdisc_skb_head *qh = &sch->q;
749
750 return qh->head;
751 }
752
753 /* generic pseudo peek method for non-work-conserving qdisc */
754 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
755 {
756 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
757 if (!sch->gso_skb) {
758 sch->gso_skb = sch->dequeue(sch);
759 if (sch->gso_skb) {
760 /* it's still part of the queue */
761 qdisc_qstats_backlog_inc(sch, sch->gso_skb);
762 sch->q.qlen++;
763 }
764 }
765
766 return sch->gso_skb;
767 }
768
769 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
770 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
771 {
772 struct sk_buff *skb = sch->gso_skb;
773
774 if (skb) {
775 sch->gso_skb = NULL;
776 qdisc_qstats_backlog_dec(sch, skb);
777 sch->q.qlen--;
778 } else {
779 skb = sch->dequeue(sch);
780 }
781
782 return skb;
783 }
784
785 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
786 {
787 /*
788 * We do not know the backlog in bytes of this list, it
789 * is up to the caller to correct it
790 */
791 ASSERT_RTNL();
792 if (qh->qlen) {
793 rtnl_kfree_skbs(qh->head, qh->tail);
794
795 qh->head = NULL;
796 qh->tail = NULL;
797 qh->qlen = 0;
798 }
799 }
800
801 static inline void qdisc_reset_queue(struct Qdisc *sch)
802 {
803 __qdisc_reset_queue(&sch->q);
804 sch->qstats.backlog = 0;
805 }
806
807 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
808 struct Qdisc **pold)
809 {
810 struct Qdisc *old;
811
812 sch_tree_lock(sch);
813 old = *pold;
814 *pold = new;
815 if (old != NULL) {
816 unsigned int qlen = old->q.qlen;
817 unsigned int backlog = old->qstats.backlog;
818
819 qdisc_reset(old);
820 qdisc_tree_reduce_backlog(old, qlen, backlog);
821 }
822 sch_tree_unlock(sch);
823
824 return old;
825 }
826
827 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
828 {
829 rtnl_kfree_skbs(skb, skb);
830 qdisc_qstats_drop(sch);
831 }
832
833
834 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
835 struct sk_buff **to_free)
836 {
837 __qdisc_drop(skb, to_free);
838 qdisc_qstats_drop(sch);
839
840 return NET_XMIT_DROP;
841 }
842
843 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
844 long it will take to send a packet given its size.
845 */
846 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
847 {
848 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
849 if (slot < 0)
850 slot = 0;
851 slot >>= rtab->rate.cell_log;
852 if (slot > 255)
853 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
854 return rtab->data[slot];
855 }
856
857 struct psched_ratecfg {
858 u64 rate_bytes_ps; /* bytes per second */
859 u32 mult;
860 u16 overhead;
861 u8 linklayer;
862 u8 shift;
863 };
864
865 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
866 unsigned int len)
867 {
868 len += r->overhead;
869
870 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
871 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
872
873 return ((u64)len * r->mult) >> r->shift;
874 }
875
876 void psched_ratecfg_precompute(struct psched_ratecfg *r,
877 const struct tc_ratespec *conf,
878 u64 rate64);
879
880 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
881 const struct psched_ratecfg *r)
882 {
883 memset(res, 0, sizeof(*res));
884
885 /* legacy struct tc_ratespec has a 32bit @rate field
886 * Qdisc using 64bit rate should add new attributes
887 * in order to maintain compatibility.
888 */
889 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
890
891 res->overhead = r->overhead;
892 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
893 }
894
895 #endif
Ubuntu Artful kernel mirror