2 * INETPEER - A storage for permanent information about peers
4 * Authors: Andrey V. Savochkin <saw@msu.ru>
7 #ifndef _NET_INETPEER_H
8 #define _NET_INETPEER_H
10 #include <linux/types.h>
11 #include <linux/init.h>
12 #include <linux/jiffies.h>
13 #include <linux/spinlock.h>
14 #include <asm/atomic.h>
22 } inet_peer_address_t;
25 /* group together avl_left,avl_right,v4daddr to speedup lookups */
26 struct inet_peer __rcu *avl_left, *avl_right;
27 inet_peer_address_t daddr;
29 struct list_head unused;
30 __u32 dtime; /* the time of last use of not
31 * referenced entries */
34 * Once inet_peer is queued for deletion (refcnt == -1), following fields
35 * are not available: rid, ip_id_count, tcp_ts, tcp_ts_stamp
36 * We can share memory with rcu_head to keep inet_peer small
37 * (less then 64 bytes)
41 atomic_t rid; /* Frag reception counter */
42 atomic_t ip_id_count; /* IP ID for the next packet */
50 void inet_initpeers(void) __init;
52 /* can be called with or without local BH being disabled */
53 struct inet_peer *inet_getpeer(__be32 daddr, int create);
55 /* can be called from BH context or outside */
56 extern void inet_putpeer(struct inet_peer *p);
59 * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,
60 * tcp_ts_stamp if no refcount is taken on inet_peer
62 static inline void inet_peer_refcheck(const struct inet_peer *p)
64 WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
68 /* can be called with or without local BH being disabled */
69 static inline __u16 inet_getid(struct inet_peer *p, int more)
72 inet_peer_refcheck(p);
73 return atomic_add_return(more, &p->ip_id_count) - more;
76 #endif /* _NET_INETPEER_H */