include/net/dst_ops.h

   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 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);
  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