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 <linux/rtnetlink.h>
16 #include <linux/atomic.h>
18 struct inetpeer_addr_base {
25 struct inetpeer_addr {
26 struct inetpeer_addr_base addr;
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;
36 u32 metrics[RTAX_MAX];
37 u32 rate_tokens; /* rate limiting for ICMP */
38 unsigned long rate_last;
39 unsigned long pmtu_expires;
42 struct inetpeer_addr_base redirect_learned;
44 struct list_head gc_list;
45 struct rcu_head gc_rcu;
48 * Once inet_peer is queued for deletion (refcnt == -1), following fields
49 * are not available: rid, ip_id_count
50 * We can share memory with rcu_head to help keep inet_peer small.
54 atomic_t rid; /* Frag reception counter */
55 atomic_t ip_id_count; /* IP ID for the next packet */
58 struct inet_peer *gc_next;
61 /* following fields might be frequently dirtied */
62 __u32 dtime; /* the time of last use of not referenced entries */
66 struct inet_peer_base {
67 struct inet_peer __rcu *root;
73 #define INETPEER_BASE_BIT 0x1UL
75 static inline struct inet_peer *inetpeer_ptr(unsigned long val)
77 BUG_ON(val & INETPEER_BASE_BIT);
78 return (struct inet_peer *) val;
81 static inline struct inet_peer_base *inetpeer_base_ptr(unsigned long val)
83 if (!(val & INETPEER_BASE_BIT))
85 val &= ~INETPEER_BASE_BIT;
86 return (struct inet_peer_base *) val;
89 static inline bool inetpeer_ptr_is_peer(unsigned long val)
91 return !(val & INETPEER_BASE_BIT);
94 static inline void __inetpeer_ptr_set_peer(unsigned long *val, struct inet_peer *peer)
96 /* This implicitly clears INETPEER_BASE_BIT */
97 *val = (unsigned long) peer;
100 static inline bool inetpeer_ptr_set_peer(unsigned long *ptr, struct inet_peer *peer)
102 unsigned long val = (unsigned long) peer;
103 unsigned long orig = *ptr;
105 if (!(orig & INETPEER_BASE_BIT) ||
106 cmpxchg(ptr, orig, val) != orig)
111 static inline void inetpeer_init_ptr(unsigned long *ptr, struct inet_peer_base *base)
113 *ptr = (unsigned long) base | INETPEER_BASE_BIT;
116 static inline void inetpeer_transfer_peer(unsigned long *to, unsigned long *from)
118 unsigned long val = *from;
121 if (inetpeer_ptr_is_peer(val)) {
122 struct inet_peer *peer = inetpeer_ptr(val);
123 atomic_inc(&peer->refcnt);
127 extern void inet_peer_base_init(struct inet_peer_base *);
129 void inet_initpeers(void) __init;
131 #define INETPEER_METRICS_NEW (~(u32) 0)
133 static inline bool inet_metrics_new(const struct inet_peer *p)
135 return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
138 /* can be called with or without local BH being disabled */
139 struct inet_peer *inet_getpeer(struct inet_peer_base *base,
140 const struct inetpeer_addr *daddr,
143 static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
147 struct inetpeer_addr daddr;
149 daddr.addr.a4 = v4daddr;
150 daddr.family = AF_INET;
151 return inet_getpeer(base, &daddr, create);
154 static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
155 const struct in6_addr *v6daddr,
158 struct inetpeer_addr daddr;
160 *(struct in6_addr *)daddr.addr.a6 = *v6daddr;
161 daddr.family = AF_INET6;
162 return inet_getpeer(base, &daddr, create);
165 /* can be called from BH context or outside */
166 extern void inet_putpeer(struct inet_peer *p);
167 extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
169 extern void inetpeer_invalidate_tree(struct inet_peer_base *);
170 extern void inetpeer_invalidate_family(int family);
173 * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,
174 * tcp_ts_stamp if no refcount is taken on inet_peer
176 static inline void inet_peer_refcheck(const struct inet_peer *p)
178 WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
182 /* can be called with or without local BH being disabled */
183 static inline int inet_getid(struct inet_peer *p, int more)
187 inet_peer_refcheck(p);
189 old = atomic_read(&p->ip_id_count);
193 } while (atomic_cmpxchg(&p->ip_id_count, old, new) != old);
197 #endif /* _NET_INETPEER_H */