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                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, 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