xref: /linux/include/net/dst_ops.h (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 #ifndef _NET_DST_OPS_H
2 #define _NET_DST_OPS_H
3 #include <linux/types.h>
4 #include <linux/percpu_counter.h>
5 #include <linux/cache.h>
6 
7 struct dst_entry;
8 struct kmem_cachep;
9 struct net_device;
10 struct sk_buff;
11 struct sock;
12 
13 struct dst_ops {
14 	unsigned short		family;
15 	unsigned int		gc_thresh;
16 
17 	int			(*gc)(struct dst_ops *ops);
18 	struct dst_entry *	(*check)(struct dst_entry *, __u32 cookie);
19 	unsigned int		(*default_advmss)(const struct dst_entry *);
20 	unsigned int		(*mtu)(const struct dst_entry *);
21 	u32 *			(*cow_metrics)(struct dst_entry *, unsigned long);
22 	void			(*destroy)(struct dst_entry *);
23 	void			(*ifdown)(struct dst_entry *,
24 					  struct net_device *dev, int how);
25 	struct dst_entry *	(*negative_advice)(struct dst_entry *);
26 	void			(*link_failure)(struct sk_buff *);
27 	void			(*update_pmtu)(struct dst_entry *dst, struct sock *sk,
28 					       struct sk_buff *skb, u32 mtu);
29 	void			(*redirect)(struct dst_entry *dst, struct sock *sk,
30 					    struct sk_buff *skb);
31 	int			(*local_out)(struct sk_buff *skb);
32 	struct neighbour *	(*neigh_lookup)(const struct dst_entry *dst,
33 						struct sk_buff *skb,
34 						const void *daddr);
35 
36 	struct kmem_cache	*kmem_cachep;
37 
38 	struct percpu_counter	pcpuc_entries ____cacheline_aligned_in_smp;
39 };
40 
41 static inline int dst_entries_get_fast(struct dst_ops *dst)
42 {
43 	return percpu_counter_read_positive(&dst->pcpuc_entries);
44 }
45 
46 static inline int dst_entries_get_slow(struct dst_ops *dst)
47 {
48 	int res;
49 
50 	local_bh_disable();
51 	res = percpu_counter_sum_positive(&dst->pcpuc_entries);
52 	local_bh_enable();
53 	return res;
54 }
55 
56 static inline void dst_entries_add(struct dst_ops *dst, int val)
57 {
58 	local_bh_disable();
59 	percpu_counter_add(&dst->pcpuc_entries, val);
60 	local_bh_enable();
61 }
62 
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 
68 static inline void dst_entries_destroy(struct dst_ops *dst)
69 {
70 	percpu_counter_destroy(&dst->pcpuc_entries);
71 }
72 
73 #endif
74