xref: /linux/include/net/dst_ops.h (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 
12 struct dst_ops {
13 	unsigned short		family;
14 	__be16			protocol;
15 	unsigned		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		(*default_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, u32 mtu);
28 	int			(*local_out)(struct sk_buff *skb);
29 	struct neighbour *	(*neigh_lookup)(const struct dst_entry *dst, const void *daddr);
30 
31 	struct kmem_cache	*kmem_cachep;
32 
33 	struct percpu_counter	pcpuc_entries ____cacheline_aligned_in_smp;
34 };
35 
36 static inline int dst_entries_get_fast(struct dst_ops *dst)
37 {
38 	return percpu_counter_read_positive(&dst->pcpuc_entries);
39 }
40 
41 static inline int dst_entries_get_slow(struct dst_ops *dst)
42 {
43 	int res;
44 
45 	local_bh_disable();
46 	res = percpu_counter_sum_positive(&dst->pcpuc_entries);
47 	local_bh_enable();
48 	return res;
49 }
50 
51 static inline void dst_entries_add(struct dst_ops *dst, int val)
52 {
53 	local_bh_disable();
54 	percpu_counter_add(&dst->pcpuc_entries, val);
55 	local_bh_enable();
56 }
57 
58 static inline int dst_entries_init(struct dst_ops *dst)
59 {
60 	return percpu_counter_init(&dst->pcpuc_entries, 0);
61 }
62 
63 static inline void dst_entries_destroy(struct dst_ops *dst)
64 {
65 	percpu_counter_destroy(&dst->pcpuc_entries);
66 }
67 
68 #endif
69