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
8 struct dst_entry;
9 struct kmem_cachep;
10 struct net_device;
11 struct sk_buff;
12 struct sock;
13 struct net;
14
15 struct 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, int how);
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
dst_entries_get_fast(struct dst_ops * dst)46 static inline int dst_entries_get_fast(struct dst_ops *dst)
47 {
48 return percpu_counter_read_positive(&dst->pcpuc_entries);
49 }
50
dst_entries_get_slow(struct dst_ops * dst)51 static 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
dst_entries_add(struct dst_ops * dst,int val)57 static 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
dst_entries_init(struct dst_ops * dst)63 static inline int dst_entries_init(struct dst_ops *dst)
64 {
65 return percpu_counter_init(&dst->pcpuc_entries, 0, GFP_KERNEL);
66 }
67
dst_entries_destroy(struct dst_ops * dst)68 static inline void dst_entries_destroy(struct dst_ops *dst)
69 {
70 percpu_counter_destroy(&dst->pcpuc_entries);
71 }
72
73 #endif
74