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            (*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
  30         struct kmem_cache       *kmem_cachep;
  31
  32         struct percpu_counter   pcpuc_entries ____cacheline_aligned_in_smp;
  33 };
  34
  35 static inline int dst_entries_get_fast(struct dst_ops *dst)
  36 {
  37         return percpu_counter_read_positive(&dst->pcpuc_entries);
  38 }
  39
  40 static inline int dst_entries_get_slow(struct dst_ops *dst)
  41 {
  42         int res;
  43
  44         local_bh_disable();
  45         res = percpu_counter_sum_positive(&dst->pcpuc_entries);
  46         local_bh_enable();
  47         return res;
  48 }
  49
  50 static inline void dst_entries_add(struct dst_ops *dst, int val)
  51 {
  52         local_bh_disable();
  53         percpu_counter_add(&dst->pcpuc_entries, val);
  54         local_bh_enable();
  55 }
  56
  57 static inline int dst_entries_init(struct dst_ops *dst)
  58 {
  59         return percpu_counter_init(&dst->pcpuc_entries, 0);
  60 }
  61
  62 static inline void dst_entries_destroy(struct dst_ops *dst)
  63 {
  64         percpu_counter_destroy(&dst->pcpuc_entries);
  65 }
  66
  67 #endif