1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _NET_DST_OPS_H
3#define _NET_DST_OPS_H
4#include <linux/types.h>
5#include <linux/percpu_counter.h>
6#include <linux/cache.h>
7
8struct dst_entry;
9struct kmem_cachep;
10struct net_device;
11struct sk_buff;
12struct sock;
13struct net;
14
15struct dst_ops {
16	unsigned short		family;
17	unsigned int		gc_thresh;
18
19	void			(*gc)(struct dst_ops *ops);
20	struct dst_entry *	(*check)(struct dst_entry *, __u32 cookie);
21	unsigned int		(*default_advmss)(const struct dst_entry *);
22	unsigned int		(*mtu)(const struct dst_entry *);
23	u32 *			(*cow_metrics)(struct dst_entry *, unsigned long);
24	void			(*destroy)(struct dst_entry *);
25	void			(*ifdown)(struct dst_entry *,
26					  struct net_device *dev);
27	struct dst_entry *	(*negative_advice)(struct dst_entry *);
28	void			(*link_failure)(struct sk_buff *);
29	void			(*update_pmtu)(struct dst_entry *dst, struct sock *sk,
30					       struct sk_buff *skb, u32 mtu,
31					       bool confirm_neigh);
32	void			(*redirect)(struct dst_entry *dst, struct sock *sk,
33					    struct sk_buff *skb);
34	int			(*local_out)(struct net *net, struct sock *sk, struct sk_buff *skb);
35	struct neighbour *	(*neigh_lookup)(const struct dst_entry *dst,
36						struct sk_buff *skb,
37						const void *daddr);
38	void			(*confirm_neigh)(const struct dst_entry *dst,
39						 const void *daddr);
40
41	struct kmem_cache	*kmem_cachep;
42
43	struct percpu_counter	pcpuc_entries ____cacheline_aligned_in_smp;
44};
45
46static inline int dst_entries_get_fast(struct dst_ops *dst)
47{
48	return percpu_counter_read_positive(&dst->pcpuc_entries);
49}
50
51static inline int dst_entries_get_slow(struct dst_ops *dst)
52{
53	return percpu_counter_sum_positive(&dst->pcpuc_entries);
54}
55
56#define DST_PERCPU_COUNTER_BATCH 32
57static inline void dst_entries_add(struct dst_ops *dst, int val)
58{
59	percpu_counter_add_batch(&dst->pcpuc_entries, val,
60				 DST_PERCPU_COUNTER_BATCH);
61}
62
63static inline int dst_entries_init(struct dst_ops *dst)
64{
65	return percpu_counter_init(&dst->pcpuc_entries, 0, GFP_KERNEL);
66}
67
68static inline void dst_entries_destroy(struct dst_ops *dst)
69{
70	percpu_counter_destroy(&dst->pcpuc_entries);
71}
72
73#endif
74