usb: cdc-acm: Fix acm_tty_hangup() vs. acm_tty_close() race
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / net / inetpeer.h
blob8a159cc3d68b49e3ac6d5d4e59bd16fa90bcc570
1 /*
2 * INETPEER - A storage for permanent information about peers
4 * Authors: Andrey V. Savochkin <saw@msu.ru>
5 */
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 <linux/rtnetlink.h>
15 #include <net/ipv6.h>
16 #include <asm/atomic.h>
18 struct inetpeer_addr_base {
19 union {
20 __be32 a4;
21 __be32 a6[4];
25 struct inetpeer_addr {
26 struct inetpeer_addr_base addr;
27 __u16 family;
30 struct inet_peer {
31 /* group together avl_left,avl_right,v4daddr to speedup lookups */
32 struct inet_peer __rcu *avl_left, *avl_right;
33 struct inetpeer_addr daddr;
34 __u32 avl_height;
35 struct list_head unused;
36 __u32 dtime; /* the time of last use of not
37 * referenced entries */
38 atomic_t refcnt;
40 * Once inet_peer is queued for deletion (refcnt == -1), following fields
41 * are not available: rid, ip_id_count, tcp_ts, tcp_ts_stamp, metrics
42 * We can share memory with rcu_head to help keep inet_peer small.
44 union {
45 struct {
46 atomic_t rid; /* Frag reception counter */
47 atomic_t ip_id_count; /* IP ID for the next packet */
48 __u32 tcp_ts;
49 __u32 tcp_ts_stamp;
50 u32 metrics[RTAX_MAX];
51 u32 rate_tokens; /* rate limiting for ICMP */
52 unsigned long rate_last;
53 unsigned long pmtu_expires;
54 u32 pmtu_orig;
55 u32 pmtu_learned;
56 struct inetpeer_addr_base redirect_learned;
58 struct rcu_head rcu;
62 void inet_initpeers(void) __init;
64 #define INETPEER_METRICS_NEW (~(u32) 0)
66 static inline bool inet_metrics_new(const struct inet_peer *p)
68 return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
71 /* can be called with or without local BH being disabled */
72 struct inet_peer *inet_getpeer(struct inetpeer_addr *daddr, int create);
74 static inline struct inet_peer *inet_getpeer_v4(__be32 v4daddr, int create)
76 struct inetpeer_addr daddr;
78 daddr.addr.a4 = v4daddr;
79 daddr.family = AF_INET;
80 return inet_getpeer(&daddr, create);
83 static inline struct inet_peer *inet_getpeer_v6(const struct in6_addr *v6daddr, int create)
85 struct inetpeer_addr daddr;
87 ipv6_addr_copy((struct in6_addr *)daddr.addr.a6, v6daddr);
88 daddr.family = AF_INET6;
89 return inet_getpeer(&daddr, create);
92 /* can be called from BH context or outside */
93 extern void inet_putpeer(struct inet_peer *p);
94 extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
97 * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,
98 * tcp_ts_stamp if no refcount is taken on inet_peer
100 static inline void inet_peer_refcheck(const struct inet_peer *p)
102 WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
106 /* can be called with or without local BH being disabled */
107 static inline __u16 inet_getid(struct inet_peer *p, int more)
109 more++;
110 inet_peer_refcheck(p);
111 return atomic_add_return(more, &p->ip_id_count) - more;
114 #endif /* _NET_INETPEER_H */