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
23struct Qdisc_ops;
24struct qdisc_walker;
25struct tcf_walker;
26struct module;
27struct bpf_flow_keys;
28
29struct qdisc_rate_table {
30 struct tc_ratespec rate;
31 u32 data[256];
32 struct qdisc_rate_table *next;
33 int refcnt;
34};
35
36enum qdisc_state_t {
37 __QDISC_STATE_SCHED,
38 __QDISC_STATE_DEACTIVATED,
39 __QDISC_STATE_MISSED,
40 __QDISC_STATE_DRAINING,
41};
42
43enum 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
56struct 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. */
65struct qdisc_skb_head {
66 struct sk_buff *head;
67 struct sk_buff *tail;
68 __u32 qlen;
69 spinlock_t lock;
70};
71
72struct 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
133static inline void qdisc_refcount_inc(struct Qdisc *qdisc)
134{
135 if (qdisc->flags & TCQ_F_BUILTIN)
136 return;
137 refcount_inc(r: &qdisc->refcnt);
138}
139
140static inline bool qdisc_refcount_dec_if_one(struct Qdisc *qdisc)
141{
142 if (qdisc->flags & TCQ_F_BUILTIN)
143 return true;
144 return refcount_dec_if_one(r: &qdisc->refcnt);
145}
146
147/* Intended to be used by unlocked users, when concurrent qdisc release is
148 * possible.
149 */
150
151static inline struct Qdisc *qdisc_refcount_inc_nz(struct Qdisc *qdisc)
152{
153 if (qdisc->flags & TCQ_F_BUILTIN)
154 return qdisc;
155 if (refcount_inc_not_zero(r: &qdisc->refcnt))
156 return qdisc;
157 return NULL;
158}
159
160/* For !TCQ_F_NOLOCK qdisc: callers must either call this within a qdisc
161 * root_lock section, or provide their own memory barriers -- ordering
162 * against qdisc_run_begin/end() atomic bit operations.
163 */
164static inline bool qdisc_is_running(struct Qdisc *qdisc)
165{
166 if (qdisc->flags & TCQ_F_NOLOCK)
167 return spin_is_locked(lock: &qdisc->seqlock);
168 return test_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
169}
170
171static inline bool nolock_qdisc_is_empty(const struct Qdisc *qdisc)
172{
173 return !(READ_ONCE(qdisc->state) & QDISC_STATE_NON_EMPTY);
174}
175
176static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
177{
178 return q->flags & TCQ_F_CPUSTATS;
179}
180
181static inline bool qdisc_is_empty(const struct Qdisc *qdisc)
182{
183 if (qdisc_is_percpu_stats(q: qdisc))
184 return nolock_qdisc_is_empty(qdisc);
185 return !READ_ONCE(qdisc->q.qlen);
186}
187
188/* For !TCQ_F_NOLOCK qdisc, qdisc_run_begin/end() must be invoked with
189 * the qdisc root lock acquired.
190 */
191static inline bool qdisc_run_begin(struct Qdisc *qdisc)
192{
193 if (qdisc->flags & TCQ_F_NOLOCK) {
194 if (spin_trylock(lock: &qdisc->seqlock))
195 return true;
196
197 /* No need to insist if the MISSED flag was already set.
198 * Note that test_and_set_bit() also gives us memory ordering
199 * guarantees wrt potential earlier enqueue() and below
200 * spin_trylock(), both of which are necessary to prevent races
201 */
202 if (test_and_set_bit(nr: __QDISC_STATE_MISSED, addr: &qdisc->state))
203 return false;
204
205 /* Try to take the lock again to make sure that we will either
206 * grab it or the CPU that still has it will see MISSED set
207 * when testing it in qdisc_run_end()
208 */
209 return spin_trylock(lock: &qdisc->seqlock);
210 }
211 return !__test_and_set_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
212}
213
214static inline void qdisc_run_end(struct Qdisc *qdisc)
215{
216 if (qdisc->flags & TCQ_F_NOLOCK) {
217 spin_unlock(lock: &qdisc->seqlock);
218
219 /* spin_unlock() only has store-release semantic. The unlock
220 * and test_bit() ordering is a store-load ordering, so a full
221 * memory barrier is needed here.
222 */
223 smp_mb();
224
225 if (unlikely(test_bit(__QDISC_STATE_MISSED,
226 &qdisc->state)))
227 __netif_schedule(q: qdisc);
228 } else {
229 __clear_bit(__QDISC_STATE2_RUNNING, &qdisc->state2);
230 }
231}
232
233static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
234{
235 return qdisc->flags & TCQ_F_ONETXQUEUE;
236}
237
238static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
239{
240#ifdef CONFIG_BQL
241 /* Non-BQL migrated drivers will return 0, too. */
242 return dql_avail(dql: &txq->dql);
243#else
244 return 0;
245#endif
246}
247
248struct Qdisc_class_ops {
249 unsigned int flags;
250 /* Child qdisc manipulation */
251 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
252 int (*graft)(struct Qdisc *, unsigned long cl,
253 struct Qdisc *, struct Qdisc **,
254 struct netlink_ext_ack *extack);
255 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
256 void (*qlen_notify)(struct Qdisc *, unsigned long);
257
258 /* Class manipulation routines */
259 unsigned long (*find)(struct Qdisc *, u32 classid);
260 int (*change)(struct Qdisc *, u32, u32,
261 struct nlattr **, unsigned long *,
262 struct netlink_ext_ack *);
263 int (*delete)(struct Qdisc *, unsigned long,
264 struct netlink_ext_ack *);
265 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
266
267 /* Filter manipulation */
268 struct tcf_block * (*tcf_block)(struct Qdisc *sch,
269 unsigned long arg,
270 struct netlink_ext_ack *extack);
271 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
272 u32 classid);
273 void (*unbind_tcf)(struct Qdisc *, unsigned long);
274
275 /* rtnetlink specific */
276 int (*dump)(struct Qdisc *, unsigned long,
277 struct sk_buff *skb, struct tcmsg*);
278 int (*dump_stats)(struct Qdisc *, unsigned long,
279 struct gnet_dump *);
280};
281
282/* Qdisc_class_ops flag values */
283
284/* Implements API that doesn't require rtnl lock */
285enum qdisc_class_ops_flags {
286 QDISC_CLASS_OPS_DOIT_UNLOCKED = 1,
287};
288
289struct Qdisc_ops {
290 struct Qdisc_ops *next;
291 const struct Qdisc_class_ops *cl_ops;
292 char id[IFNAMSIZ];
293 int priv_size;
294 unsigned int static_flags;
295
296 int (*enqueue)(struct sk_buff *skb,
297 struct Qdisc *sch,
298 struct sk_buff **to_free);
299 struct sk_buff * (*dequeue)(struct Qdisc *);
300 struct sk_buff * (*peek)(struct Qdisc *);
301
302 int (*init)(struct Qdisc *sch, struct nlattr *arg,
303 struct netlink_ext_ack *extack);
304 void (*reset)(struct Qdisc *);
305 void (*destroy)(struct Qdisc *);
306 int (*change)(struct Qdisc *sch,
307 struct nlattr *arg,
308 struct netlink_ext_ack *extack);
309 void (*attach)(struct Qdisc *sch);
310 int (*change_tx_queue_len)(struct Qdisc *, unsigned int);
311 void (*change_real_num_tx)(struct Qdisc *sch,
312 unsigned int new_real_tx);
313
314 int (*dump)(struct Qdisc *, struct sk_buff *);
315 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
316
317 void (*ingress_block_set)(struct Qdisc *sch,
318 u32 block_index);
319 void (*egress_block_set)(struct Qdisc *sch,
320 u32 block_index);
321 u32 (*ingress_block_get)(struct Qdisc *sch);
322 u32 (*egress_block_get)(struct Qdisc *sch);
323
324 struct module *owner;
325};
326
327struct tcf_result {
328 union {
329 struct {
330 unsigned long class;
331 u32 classid;
332 };
333 const struct tcf_proto *goto_tp;
334 };
335 enum skb_drop_reason drop_reason;
336};
337
338struct tcf_chain;
339
340struct tcf_proto_ops {
341 struct list_head head;
342 char kind[IFNAMSIZ];
343
344 int (*classify)(struct sk_buff *,
345 const struct tcf_proto *,
346 struct tcf_result *);
347 int (*init)(struct tcf_proto*);
348 void (*destroy)(struct tcf_proto *tp, bool rtnl_held,
349 struct netlink_ext_ack *extack);
350
351 void* (*get)(struct tcf_proto*, u32 handle);
352 void (*put)(struct tcf_proto *tp, void *f);
353 int (*change)(struct net *net, struct sk_buff *,
354 struct tcf_proto*, unsigned long,
355 u32 handle, struct nlattr **,
356 void **, u32,
357 struct netlink_ext_ack *);
358 int (*delete)(struct tcf_proto *tp, void *arg,
359 bool *last, bool rtnl_held,
360 struct netlink_ext_ack *);
361 bool (*delete_empty)(struct tcf_proto *tp);
362 void (*walk)(struct tcf_proto *tp,
363 struct tcf_walker *arg, bool rtnl_held);
364 int (*reoffload)(struct tcf_proto *tp, bool add,
365 flow_setup_cb_t *cb, void *cb_priv,
366 struct netlink_ext_ack *extack);
367 void (*hw_add)(struct tcf_proto *tp,
368 void *type_data);
369 void (*hw_del)(struct tcf_proto *tp,
370 void *type_data);
371 void (*bind_class)(void *, u32, unsigned long,
372 void *, unsigned long);
373 void * (*tmplt_create)(struct net *net,
374 struct tcf_chain *chain,
375 struct nlattr **tca,
376 struct netlink_ext_ack *extack);
377 void (*tmplt_destroy)(void *tmplt_priv);
378 struct tcf_exts * (*get_exts)(const struct tcf_proto *tp,
379 u32 handle);
380
381 /* rtnetlink specific */
382 int (*dump)(struct net*, struct tcf_proto*, void *,
383 struct sk_buff *skb, struct tcmsg*,
384 bool);
385 int (*terse_dump)(struct net *net,
386 struct tcf_proto *tp, void *fh,
387 struct sk_buff *skb,
388 struct tcmsg *t, bool rtnl_held);
389 int (*tmplt_dump)(struct sk_buff *skb,
390 struct net *net,
391 void *tmplt_priv);
392
393 struct module *owner;
394 int flags;
395};
396
397/* Classifiers setting TCF_PROTO_OPS_DOIT_UNLOCKED in tcf_proto_ops->flags
398 * are expected to implement tcf_proto_ops->delete_empty(), otherwise race
399 * conditions can occur when filters are inserted/deleted simultaneously.
400 */
401enum tcf_proto_ops_flags {
402 TCF_PROTO_OPS_DOIT_UNLOCKED = 1,
403};
404
405struct tcf_proto {
406 /* Fast access part */
407 struct tcf_proto __rcu *next;
408 void __rcu *root;
409
410 /* called under RCU BH lock*/
411 int (*classify)(struct sk_buff *,
412 const struct tcf_proto *,
413 struct tcf_result *);
414 __be16 protocol;
415
416 /* All the rest */
417 u32 prio;
418 void *data;
419 const struct tcf_proto_ops *ops;
420 struct tcf_chain *chain;
421 /* Lock protects tcf_proto shared state and can be used by unlocked
422 * classifiers to protect their private data.
423 */
424 spinlock_t lock;
425 bool deleting;
426 refcount_t refcnt;
427 struct rcu_head rcu;
428 struct hlist_node destroy_ht_node;
429};
430
431struct qdisc_skb_cb {
432 struct {
433 unsigned int pkt_len;
434 u16 slave_dev_queue_mapping;
435 u16 tc_classid;
436 };
437#define QDISC_CB_PRIV_LEN 20
438 unsigned char data[QDISC_CB_PRIV_LEN];
439};
440
441typedef void tcf_chain_head_change_t(struct tcf_proto *tp_head, void *priv);
442
443struct tcf_chain {
444 /* Protects filter_chain. */
445 struct mutex filter_chain_lock;
446 struct tcf_proto __rcu *filter_chain;
447 struct list_head list;
448 struct tcf_block *block;
449 u32 index; /* chain index */
450 unsigned int refcnt;
451 unsigned int action_refcnt;
452 bool explicitly_created;
453 bool flushing;
454 const struct tcf_proto_ops *tmplt_ops;
455 void *tmplt_priv;
456 struct rcu_head rcu;
457};
458
459struct tcf_block {
460 /* Lock protects tcf_block and lifetime-management data of chains
461 * attached to the block (refcnt, action_refcnt, explicitly_created).
462 */
463 struct mutex lock;
464 struct list_head chain_list;
465 u32 index; /* block index for shared blocks */
466 u32 classid; /* which class this block belongs to */
467 refcount_t refcnt;
468 struct net *net;
469 struct Qdisc *q;
470 struct rw_semaphore cb_lock; /* protects cb_list and offload counters */
471 struct flow_block flow_block;
472 struct list_head owner_list;
473 bool keep_dst;
474 atomic_t offloadcnt; /* Number of oddloaded filters */
475 unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
476 unsigned int lockeddevcnt; /* Number of devs that require rtnl lock. */
477 struct {
478 struct tcf_chain *chain;
479 struct list_head filter_chain_list;
480 } chain0;
481 struct rcu_head rcu;
482 DECLARE_HASHTABLE(proto_destroy_ht, 7);
483 struct mutex proto_destroy_lock; /* Lock for proto_destroy hashtable. */
484};
485
486static inline bool lockdep_tcf_chain_is_locked(struct tcf_chain *chain)
487{
488 return lockdep_is_held(&chain->filter_chain_lock);
489}
490
491static inline bool lockdep_tcf_proto_is_locked(struct tcf_proto *tp)
492{
493 return lockdep_is_held(&tp->lock);
494}
495
496#define tcf_chain_dereference(p, chain) \
497 rcu_dereference_protected(p, lockdep_tcf_chain_is_locked(chain))
498
499#define tcf_proto_dereference(p, tp) \
500 rcu_dereference_protected(p, lockdep_tcf_proto_is_locked(tp))
501
502static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
503{
504 struct qdisc_skb_cb *qcb;
505
506 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*qcb));
507 BUILD_BUG_ON(sizeof(qcb->data) < sz);
508}
509
510static inline int qdisc_qlen(const struct Qdisc *q)
511{
512 return q->q.qlen;
513}
514
515static inline int qdisc_qlen_sum(const struct Qdisc *q)
516{
517 __u32 qlen = q->qstats.qlen;
518 int i;
519
520 if (qdisc_is_percpu_stats(q)) {
521 for_each_possible_cpu(i)
522 qlen += per_cpu_ptr(q->cpu_qstats, i)->qlen;
523 } else {
524 qlen += q->q.qlen;
525 }
526
527 return qlen;
528}
529
530static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
531{
532 return (struct qdisc_skb_cb *)skb->cb;
533}
534
535static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
536{
537 return &qdisc->q.lock;
538}
539
540static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
541{
542 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
543
544 return q;
545}
546
547static inline struct Qdisc *qdisc_root_bh(const struct Qdisc *qdisc)
548{
549 return rcu_dereference_bh(qdisc->dev_queue->qdisc);
550}
551
552static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
553{
554 return rcu_dereference_rtnl(qdisc->dev_queue->qdisc_sleeping);
555}
556
557static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
558{
559 struct Qdisc *root = qdisc_root_sleeping(qdisc);
560
561 ASSERT_RTNL();
562 return qdisc_lock(qdisc: root);
563}
564
565static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
566{
567 return qdisc->dev_queue->dev;
568}
569
570static inline void sch_tree_lock(struct Qdisc *q)
571{
572 if (q->flags & TCQ_F_MQROOT)
573 spin_lock_bh(lock: qdisc_lock(qdisc: q));
574 else
575 spin_lock_bh(lock: qdisc_root_sleeping_lock(qdisc: q));
576}
577
578static inline void sch_tree_unlock(struct Qdisc *q)
579{
580 if (q->flags & TCQ_F_MQROOT)
581 spin_unlock_bh(lock: qdisc_lock(qdisc: q));
582 else
583 spin_unlock_bh(lock: qdisc_root_sleeping_lock(qdisc: q));
584}
585
586extern struct Qdisc noop_qdisc;
587extern struct Qdisc_ops noop_qdisc_ops;
588extern struct Qdisc_ops pfifo_fast_ops;
589extern const u8 sch_default_prio2band[TC_PRIO_MAX + 1];
590extern struct Qdisc_ops mq_qdisc_ops;
591extern struct Qdisc_ops noqueue_qdisc_ops;
592extern const struct Qdisc_ops *default_qdisc_ops;
593static inline const struct Qdisc_ops *
594get_default_qdisc_ops(const struct net_device *dev, int ntx)
595{
596 return ntx < dev->real_num_tx_queues ?
597 default_qdisc_ops : &pfifo_fast_ops;
598}
599
600struct Qdisc_class_common {
601 u32 classid;
602 unsigned int filter_cnt;
603 struct hlist_node hnode;
604};
605
606struct Qdisc_class_hash {
607 struct hlist_head *hash;
608 unsigned int hashsize;
609 unsigned int hashmask;
610 unsigned int hashelems;
611};
612
613static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
614{
615 id ^= id >> 8;
616 id ^= id >> 4;
617 return id & mask;
618}
619
620static inline struct Qdisc_class_common *
621qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
622{
623 struct Qdisc_class_common *cl;
624 unsigned int h;
625
626 if (!id)
627 return NULL;
628
629 h = qdisc_class_hash(id, mask: hash->hashmask);
630 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
631 if (cl->classid == id)
632 return cl;
633 }
634 return NULL;
635}
636
637static inline bool qdisc_class_in_use(const struct Qdisc_class_common *cl)
638{
639 return cl->filter_cnt > 0;
640}
641
642static inline void qdisc_class_get(struct Qdisc_class_common *cl)
643{
644 unsigned int res;
645
646 if (check_add_overflow(cl->filter_cnt, 1, &res))
647 WARN(1, "Qdisc class overflow");
648
649 cl->filter_cnt = res;
650}
651
652static inline void qdisc_class_put(struct Qdisc_class_common *cl)
653{
654 unsigned int res;
655
656 if (check_sub_overflow(cl->filter_cnt, 1, &res))
657 WARN(1, "Qdisc class underflow");
658
659 cl->filter_cnt = res;
660}
661
662static inline int tc_classid_to_hwtc(struct net_device *dev, u32 classid)
663{
664 u32 hwtc = TC_H_MIN(classid) - TC_H_MIN_PRIORITY;
665
666 return (hwtc < netdev_get_num_tc(dev)) ? hwtc : -EINVAL;
667}
668
669int qdisc_class_hash_init(struct Qdisc_class_hash *);
670void qdisc_class_hash_insert(struct Qdisc_class_hash *,
671 struct Qdisc_class_common *);
672void qdisc_class_hash_remove(struct Qdisc_class_hash *,
673 struct Qdisc_class_common *);
674void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
675void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
676
677int dev_qdisc_change_tx_queue_len(struct net_device *dev);
678void dev_qdisc_change_real_num_tx(struct net_device *dev,
679 unsigned int new_real_tx);
680void dev_init_scheduler(struct net_device *dev);
681void dev_shutdown(struct net_device *dev);
682void dev_activate(struct net_device *dev);
683void dev_deactivate(struct net_device *dev);
684void dev_deactivate_many(struct list_head *head);
685struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
686 struct Qdisc *qdisc);
687void qdisc_reset(struct Qdisc *qdisc);
688void qdisc_destroy(struct Qdisc *qdisc);
689void qdisc_put(struct Qdisc *qdisc);
690void qdisc_put_unlocked(struct Qdisc *qdisc);
691void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, int n, int len);
692#ifdef CONFIG_NET_SCHED
693int qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
694 void *type_data);
695void qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
696 struct Qdisc *new, struct Qdisc *old,
697 enum tc_setup_type type, void *type_data,
698 struct netlink_ext_ack *extack);
699#else
700static inline int
701qdisc_offload_dump_helper(struct Qdisc *q, enum tc_setup_type type,
702 void *type_data)
703{
704 q->flags &= ~TCQ_F_OFFLOADED;
705 return 0;
706}
707
708static inline void
709qdisc_offload_graft_helper(struct net_device *dev, struct Qdisc *sch,
710 struct Qdisc *new, struct Qdisc *old,
711 enum tc_setup_type type, void *type_data,
712 struct netlink_ext_ack *extack)
713{
714}
715#endif
716void qdisc_offload_query_caps(struct net_device *dev,
717 enum tc_setup_type type,
718 void *caps, size_t caps_len);
719struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
720 const struct Qdisc_ops *ops,
721 struct netlink_ext_ack *extack);
722void qdisc_free(struct Qdisc *qdisc);
723struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
724 const struct Qdisc_ops *ops, u32 parentid,
725 struct netlink_ext_ack *extack);
726void __qdisc_calculate_pkt_len(struct sk_buff *skb,
727 const struct qdisc_size_table *stab);
728int skb_do_redirect(struct sk_buff *);
729
730static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
731{
732#ifdef CONFIG_NET_XGRESS
733 return skb->tc_at_ingress;
734#else
735 return false;
736#endif
737}
738
739static inline bool skb_skip_tc_classify(struct sk_buff *skb)
740{
741#ifdef CONFIG_NET_CLS_ACT
742 if (skb->tc_skip_classify) {
743 skb->tc_skip_classify = 0;
744 return true;
745 }
746#endif
747 return false;
748}
749
750/* Reset all TX qdiscs greater than index of a device. */
751static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
752{
753 struct Qdisc *qdisc;
754
755 for (; i < dev->num_tx_queues; i++) {
756 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
757 if (qdisc) {
758 spin_lock_bh(lock: qdisc_lock(qdisc));
759 qdisc_reset(qdisc);
760 spin_unlock_bh(lock: qdisc_lock(qdisc));
761 }
762 }
763}
764
765/* Are all TX queues of the device empty? */
766static inline bool qdisc_all_tx_empty(const struct net_device *dev)
767{
768 unsigned int i;
769
770 rcu_read_lock();
771 for (i = 0; i < dev->num_tx_queues; i++) {
772 struct netdev_queue *txq = netdev_get_tx_queue(dev, index: i);
773 const struct Qdisc *q = rcu_dereference(txq->qdisc);
774
775 if (!qdisc_is_empty(qdisc: q)) {
776 rcu_read_unlock();
777 return false;
778 }
779 }
780 rcu_read_unlock();
781 return true;
782}
783
784/* Are any of the TX qdiscs changing? */
785static inline bool qdisc_tx_changing(const struct net_device *dev)
786{
787 unsigned int i;
788
789 for (i = 0; i < dev->num_tx_queues; i++) {
790 struct netdev_queue *txq = netdev_get_tx_queue(dev, index: i);
791
792 if (rcu_access_pointer(txq->qdisc) !=
793 rcu_access_pointer(txq->qdisc_sleeping))
794 return true;
795 }
796 return false;
797}
798
799/* Is the device using the noop qdisc on all queues? */
800static inline bool qdisc_tx_is_noop(const struct net_device *dev)
801{
802 unsigned int i;
803
804 for (i = 0; i < dev->num_tx_queues; i++) {
805 struct netdev_queue *txq = netdev_get_tx_queue(dev, index: i);
806 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
807 return false;
808 }
809 return true;
810}
811
812static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
813{
814 return qdisc_skb_cb(skb)->pkt_len;
815}
816
817/* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
818enum net_xmit_qdisc_t {
819 __NET_XMIT_STOLEN = 0x00010000,
820 __NET_XMIT_BYPASS = 0x00020000,
821};
822
823#ifdef CONFIG_NET_CLS_ACT
824#define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
825#else
826#define net_xmit_drop_count(e) (1)
827#endif
828
829static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
830 const struct Qdisc *sch)
831{
832#ifdef CONFIG_NET_SCHED
833 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
834
835 if (stab)
836 __qdisc_calculate_pkt_len(skb, stab);
837#endif
838}
839
840static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
841 struct sk_buff **to_free)
842{
843 qdisc_calculate_pkt_len(skb, sch);
844 return sch->enqueue(skb, sch, to_free);
845}
846
847static inline void _bstats_update(struct gnet_stats_basic_sync *bstats,
848 __u64 bytes, __u32 packets)
849{
850 u64_stats_update_begin(syncp: &bstats->syncp);
851 u64_stats_add(p: &bstats->bytes, val: bytes);
852 u64_stats_add(p: &bstats->packets, val: packets);
853 u64_stats_update_end(syncp: &bstats->syncp);
854}
855
856static inline void bstats_update(struct gnet_stats_basic_sync *bstats,
857 const struct sk_buff *skb)
858{
859 _bstats_update(bstats,
860 bytes: qdisc_pkt_len(skb),
861 packets: skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
862}
863
864static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
865 const struct sk_buff *skb)
866{
867 bstats_update(this_cpu_ptr(sch->cpu_bstats), skb);
868}
869
870static inline void qdisc_bstats_update(struct Qdisc *sch,
871 const struct sk_buff *skb)
872{
873 bstats_update(bstats: &sch->bstats, skb);
874}
875
876static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
877 const struct sk_buff *skb)
878{
879 sch->qstats.backlog -= qdisc_pkt_len(skb);
880}
881
882static inline void qdisc_qstats_cpu_backlog_dec(struct Qdisc *sch,
883 const struct sk_buff *skb)
884{
885 this_cpu_sub(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
886}
887
888static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
889 const struct sk_buff *skb)
890{
891 sch->qstats.backlog += qdisc_pkt_len(skb);
892}
893
894static inline void qdisc_qstats_cpu_backlog_inc(struct Qdisc *sch,
895 const struct sk_buff *skb)
896{
897 this_cpu_add(sch->cpu_qstats->backlog, qdisc_pkt_len(skb));
898}
899
900static inline void qdisc_qstats_cpu_qlen_inc(struct Qdisc *sch)
901{
902 this_cpu_inc(sch->cpu_qstats->qlen);
903}
904
905static inline void qdisc_qstats_cpu_qlen_dec(struct Qdisc *sch)
906{
907 this_cpu_dec(sch->cpu_qstats->qlen);
908}
909
910static inline void qdisc_qstats_cpu_requeues_inc(struct Qdisc *sch)
911{
912 this_cpu_inc(sch->cpu_qstats->requeues);
913}
914
915static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
916{
917 sch->qstats.drops += count;
918}
919
920static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
921{
922 qstats->drops++;
923}
924
925static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
926{
927 qstats->overlimits++;
928}
929
930static inline void qdisc_qstats_drop(struct Qdisc *sch)
931{
932 qstats_drop_inc(qstats: &sch->qstats);
933}
934
935static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
936{
937 this_cpu_inc(sch->cpu_qstats->drops);
938}
939
940static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
941{
942 sch->qstats.overlimits++;
943}
944
945static inline int qdisc_qstats_copy(struct gnet_dump *d, struct Qdisc *sch)
946{
947 __u32 qlen = qdisc_qlen_sum(q: sch);
948
949 return gnet_stats_copy_queue(d, cpu_q: sch->cpu_qstats, q: &sch->qstats, qlen);
950}
951
952static inline void qdisc_qstats_qlen_backlog(struct Qdisc *sch, __u32 *qlen,
953 __u32 *backlog)
954{
955 struct gnet_stats_queue qstats = { 0 };
956
957 gnet_stats_add_queue(qstats: &qstats, cpu_q: sch->cpu_qstats, q: &sch->qstats);
958 *qlen = qstats.qlen + qdisc_qlen(q: sch);
959 *backlog = qstats.backlog;
960}
961
962static inline void qdisc_tree_flush_backlog(struct Qdisc *sch)
963{
964 __u32 qlen, backlog;
965
966 qdisc_qstats_qlen_backlog(sch, qlen: &qlen, backlog: &backlog);
967 qdisc_tree_reduce_backlog(qdisc: sch, n: qlen, len: backlog);
968}
969
970static inline void qdisc_purge_queue(struct Qdisc *sch)
971{
972 __u32 qlen, backlog;
973
974 qdisc_qstats_qlen_backlog(sch, qlen: &qlen, backlog: &backlog);
975 qdisc_reset(qdisc: sch);
976 qdisc_tree_reduce_backlog(qdisc: sch, n: qlen, len: backlog);
977}
978
979static inline void __qdisc_enqueue_tail(struct sk_buff *skb,
980 struct qdisc_skb_head *qh)
981{
982 struct sk_buff *last = qh->tail;
983
984 if (last) {
985 skb->next = NULL;
986 last->next = skb;
987 qh->tail = skb;
988 } else {
989 qh->tail = skb;
990 qh->head = skb;
991 }
992 qh->qlen++;
993}
994
995static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
996{
997 __qdisc_enqueue_tail(skb, qh: &sch->q);
998 qdisc_qstats_backlog_inc(sch, skb);
999 return NET_XMIT_SUCCESS;
1000}
1001
1002static inline void __qdisc_enqueue_head(struct sk_buff *skb,
1003 struct qdisc_skb_head *qh)
1004{
1005 skb->next = qh->head;
1006
1007 if (!qh->head)
1008 qh->tail = skb;
1009 qh->head = skb;
1010 qh->qlen++;
1011}
1012
1013static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
1014{
1015 struct sk_buff *skb = qh->head;
1016
1017 if (likely(skb != NULL)) {
1018 qh->head = skb->next;
1019 qh->qlen--;
1020 if (qh->head == NULL)
1021 qh->tail = NULL;
1022 skb->next = NULL;
1023 }
1024
1025 return skb;
1026}
1027
1028static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
1029{
1030 struct sk_buff *skb = __qdisc_dequeue_head(qh: &sch->q);
1031
1032 if (likely(skb != NULL)) {
1033 qdisc_qstats_backlog_dec(sch, skb);
1034 qdisc_bstats_update(sch, skb);
1035 }
1036
1037 return skb;
1038}
1039
1040/* Instead of calling kfree_skb() while root qdisc lock is held,
1041 * queue the skb for future freeing at end of __dev_xmit_skb()
1042 */
1043static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
1044{
1045 skb->next = *to_free;
1046 *to_free = skb;
1047}
1048
1049static inline void __qdisc_drop_all(struct sk_buff *skb,
1050 struct sk_buff **to_free)
1051{
1052 if (skb->prev)
1053 skb->prev->next = *to_free;
1054 else
1055 skb->next = *to_free;
1056 *to_free = skb;
1057}
1058
1059static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
1060 struct qdisc_skb_head *qh,
1061 struct sk_buff **to_free)
1062{
1063 struct sk_buff *skb = __qdisc_dequeue_head(qh);
1064
1065 if (likely(skb != NULL)) {
1066 unsigned int len = qdisc_pkt_len(skb);
1067
1068 qdisc_qstats_backlog_dec(sch, skb);
1069 __qdisc_drop(skb, to_free);
1070 return len;
1071 }
1072
1073 return 0;
1074}
1075
1076static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
1077{
1078 const struct qdisc_skb_head *qh = &sch->q;
1079
1080 return qh->head;
1081}
1082
1083/* generic pseudo peek method for non-work-conserving qdisc */
1084static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
1085{
1086 struct sk_buff *skb = skb_peek(list_: &sch->gso_skb);
1087
1088 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
1089 if (!skb) {
1090 skb = sch->dequeue(sch);
1091
1092 if (skb) {
1093 __skb_queue_head(list: &sch->gso_skb, newsk: skb);
1094 /* it's still part of the queue */
1095 qdisc_qstats_backlog_inc(sch, skb);
1096 sch->q.qlen++;
1097 }
1098 }
1099
1100 return skb;
1101}
1102
1103static inline void qdisc_update_stats_at_dequeue(struct Qdisc *sch,
1104 struct sk_buff *skb)
1105{
1106 if (qdisc_is_percpu_stats(q: sch)) {
1107 qdisc_qstats_cpu_backlog_dec(sch, skb);
1108 qdisc_bstats_cpu_update(sch, skb);
1109 qdisc_qstats_cpu_qlen_dec(sch);
1110 } else {
1111 qdisc_qstats_backlog_dec(sch, skb);
1112 qdisc_bstats_update(sch, skb);
1113 sch->q.qlen--;
1114 }
1115}
1116
1117static inline void qdisc_update_stats_at_enqueue(struct Qdisc *sch,
1118 unsigned int pkt_len)
1119{
1120 if (qdisc_is_percpu_stats(q: sch)) {
1121 qdisc_qstats_cpu_qlen_inc(sch);
1122 this_cpu_add(sch->cpu_qstats->backlog, pkt_len);
1123 } else {
1124 sch->qstats.backlog += pkt_len;
1125 sch->q.qlen++;
1126 }
1127}
1128
1129/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
1130static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
1131{
1132 struct sk_buff *skb = skb_peek(list_: &sch->gso_skb);
1133
1134 if (skb) {
1135 skb = __skb_dequeue(list: &sch->gso_skb);
1136 if (qdisc_is_percpu_stats(q: sch)) {
1137 qdisc_qstats_cpu_backlog_dec(sch, skb);
1138 qdisc_qstats_cpu_qlen_dec(sch);
1139 } else {
1140 qdisc_qstats_backlog_dec(sch, skb);
1141 sch->q.qlen--;
1142 }
1143 } else {
1144 skb = sch->dequeue(sch);
1145 }
1146
1147 return skb;
1148}
1149
1150static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
1151{
1152 /*
1153 * We do not know the backlog in bytes of this list, it
1154 * is up to the caller to correct it
1155 */
1156 ASSERT_RTNL();
1157 if (qh->qlen) {
1158 rtnl_kfree_skbs(head: qh->head, tail: qh->tail);
1159
1160 qh->head = NULL;
1161 qh->tail = NULL;
1162 qh->qlen = 0;
1163 }
1164}
1165
1166static inline void qdisc_reset_queue(struct Qdisc *sch)
1167{
1168 __qdisc_reset_queue(qh: &sch->q);
1169}
1170
1171static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
1172 struct Qdisc **pold)
1173{
1174 struct Qdisc *old;
1175
1176 sch_tree_lock(q: sch);
1177 old = *pold;
1178 *pold = new;
1179 if (old != NULL)
1180 qdisc_purge_queue(sch: old);
1181 sch_tree_unlock(q: sch);
1182
1183 return old;
1184}
1185
1186static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
1187{
1188 rtnl_kfree_skbs(head: skb, tail: skb);
1189 qdisc_qstats_drop(sch);
1190}
1191
1192static inline int qdisc_drop_cpu(struct sk_buff *skb, struct Qdisc *sch,
1193 struct sk_buff **to_free)
1194{
1195 __qdisc_drop(skb, to_free);
1196 qdisc_qstats_cpu_drop(sch);
1197
1198 return NET_XMIT_DROP;
1199}
1200
1201static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
1202 struct sk_buff **to_free)
1203{
1204 __qdisc_drop(skb, to_free);
1205 qdisc_qstats_drop(sch);
1206
1207 return NET_XMIT_DROP;
1208}
1209
1210static inline int qdisc_drop_all(struct sk_buff *skb, struct Qdisc *sch,
1211 struct sk_buff **to_free)
1212{
1213 __qdisc_drop_all(skb, to_free);
1214 qdisc_qstats_drop(sch);
1215
1216 return NET_XMIT_DROP;
1217}
1218
1219struct psched_ratecfg {
1220 u64 rate_bytes_ps; /* bytes per second */
1221 u32 mult;
1222 u16 overhead;
1223 u16 mpu;
1224 u8 linklayer;
1225 u8 shift;
1226};
1227
1228static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
1229 unsigned int len)
1230{
1231 len += r->overhead;
1232
1233 if (len < r->mpu)
1234 len = r->mpu;
1235
1236 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
1237 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
1238
1239 return ((u64)len * r->mult) >> r->shift;
1240}
1241
1242void psched_ratecfg_precompute(struct psched_ratecfg *r,
1243 const struct tc_ratespec *conf,
1244 u64 rate64);
1245
1246static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
1247 const struct psched_ratecfg *r)
1248{
1249 memset(res, 0, sizeof(*res));
1250
1251 /* legacy struct tc_ratespec has a 32bit @rate field
1252 * Qdisc using 64bit rate should add new attributes
1253 * in order to maintain compatibility.
1254 */
1255 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
1256
1257 res->overhead = r->overhead;
1258 res->mpu = r->mpu;
1259 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
1260}
1261
1262struct psched_pktrate {
1263 u64 rate_pkts_ps; /* packets per second */
1264 u32 mult;
1265 u8 shift;
1266};
1267
1268static inline u64 psched_pkt2t_ns(const struct psched_pktrate *r,
1269 unsigned int pkt_num)
1270{
1271 return ((u64)pkt_num * r->mult) >> r->shift;
1272}
1273
1274void psched_ppscfg_precompute(struct psched_pktrate *r, u64 pktrate64);
1275
1276/* Mini Qdisc serves for specific needs of ingress/clsact Qdisc.
1277 * The fast path only needs to access filter list and to update stats
1278 */
1279struct mini_Qdisc {
1280 struct tcf_proto *filter_list;
1281 struct tcf_block *block;
1282 struct gnet_stats_basic_sync __percpu *cpu_bstats;
1283 struct gnet_stats_queue __percpu *cpu_qstats;
1284 unsigned long rcu_state;
1285};
1286
1287static inline void mini_qdisc_bstats_cpu_update(struct mini_Qdisc *miniq,
1288 const struct sk_buff *skb)
1289{
1290 bstats_update(this_cpu_ptr(miniq->cpu_bstats), skb);
1291}
1292
1293static inline void mini_qdisc_qstats_cpu_drop(struct mini_Qdisc *miniq)
1294{
1295 this_cpu_inc(miniq->cpu_qstats->drops);
1296}
1297
1298struct mini_Qdisc_pair {
1299 struct mini_Qdisc miniq1;
1300 struct mini_Qdisc miniq2;
1301 struct mini_Qdisc __rcu **p_miniq;
1302};
1303
1304void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp,
1305 struct tcf_proto *tp_head);
1306void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc,
1307 struct mini_Qdisc __rcu **p_miniq);
1308void mini_qdisc_pair_block_init(struct mini_Qdisc_pair *miniqp,
1309 struct tcf_block *block);
1310
1311void mq_change_real_num_tx(struct Qdisc *sch, unsigned int new_real_tx);
1312
1313int sch_frag_xmit_hook(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb));
1314
1315/* Make sure qdisc is no longer in SCHED state. */
1316static inline void qdisc_synchronize(const struct Qdisc *q)
1317{
1318 while (test_bit(__QDISC_STATE_SCHED, &q->state))
1319 msleep(msecs: 1);
1320}
1321
1322#endif
1323

source code of linux/include/net/sch_generic.h