include/net/inetpeer.h

   1 /*
   2  *              INETPEER - A storage for permanent information about peers
   3  *
   4  *  Version:    $Id: inetpeer.h,v 1.2 2002/01/12 07:54:56 davem Exp $
   5  *
   6  *  Authors:    Andrey V. Savochkin <saw@msu.ru>
   7  */
   8
   9 #ifndef _NET_INETPEER_H
  10 #define _NET_INETPEER_H
  11
  12 #include <linux/types.h>
  13 #include <linux/init.h>
  14 #include <linux/jiffies.h>
  15 #include <linux/spinlock.h>
  16 #include <asm/atomic.h>
  17
  18 struct inet_peer
  19 {
  20         struct inet_peer        *avl_left, *avl_right;
  21         struct inet_peer        *unused_next, **unused_prevp;
  22         unsigned long           dtime;          /* the time of last use of not
  23                                                  * referenced entries */
  24         atomic_t                refcnt;
  25         __u32                   v4daddr;        /* peer's address */
  26         __u16                   avl_height;
  27         __u16                   ip_id_count;    /* IP ID for the next packet */
  28         atomic_t                rid;            /* Frag reception counter */
  29         __u32                   tcp_ts;
  30         unsigned long           tcp_ts_stamp;
  31 };
  32
  33 void                    inet_initpeers(void) __init;
  34
  35 /* can be called with or without local BH being disabled */
  36 struct inet_peer        *inet_getpeer(__u32 daddr, int create);
  37
  38 extern spinlock_t inet_peer_unused_lock;
  39 extern struct inet_peer **inet_peer_unused_tailp;
  40 /* can be called from BH context or outside */
  41 static inline void      inet_putpeer(struct inet_peer *p)
  42 {
  43         spin_lock_bh(&inet_peer_unused_lock);
  44         if (atomic_dec_and_test(&p->refcnt)) {
  45                 p->unused_prevp = inet_peer_unused_tailp;
  46                 p->unused_next = NULL;
  47                 *inet_peer_unused_tailp = p;
  48                 inet_peer_unused_tailp = &p->unused_next;
  49                 p->dtime = jiffies;
  50         }
  51         spin_unlock_bh(&inet_peer_unused_lock);
  52 }
  53
  54 extern spinlock_t inet_peer_idlock;
  55 /* can be called with or without local BH being disabled */
  56 static inline __u16     inet_getid(struct inet_peer *p, int more)
  57 {
  58         __u16 id;
  59
  60         spin_lock_bh(&inet_peer_idlock);
  61         id = p->ip_id_count;
  62         p->ip_id_count += 1 + more;
  63         spin_unlock_bh(&inet_peer_idlock);
  64         return id;
  65 }
  66
  67 #endif /* _NET_INETPEER_H */