2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * Definitions for a generic INET TIMEWAIT sock
8 * From code originally in net/tcp.h
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
15 #ifndef _INET_TIMEWAIT_SOCK_
16 #define _INET_TIMEWAIT_SOCK_
18 #include <linux/config.h>
21 #include <linux/list.h>
22 #include <linux/types.h>
25 #include <net/tcp_states.h>
27 #include <asm/atomic.h>
29 #if (BITS_PER_LONG == 64)
30 #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 8
32 #define INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES 4
35 struct inet_bind_bucket;
39 * This is a TIME_WAIT sock. It works around the memory consumption
40 * problems of sockets in such a state on heavily loaded servers, but
41 * without violating the protocol specification.
43 struct inet_timewait_sock {
45 * Now struct sock also uses sock_common, so please just
46 * don't add nothing before this first member (__tw_common) --acme
48 struct sock_common __tw_common;
49 #define tw_family __tw_common.skc_family
50 #define tw_state __tw_common.skc_state
51 #define tw_reuse __tw_common.skc_reuse
52 #define tw_bound_dev_if __tw_common.skc_bound_dev_if
53 #define tw_node __tw_common.skc_node
54 #define tw_bind_node __tw_common.skc_bind_node
55 #define tw_refcnt __tw_common.skc_refcnt
56 #define tw_prot __tw_common.skc_prot
57 volatile unsigned char tw_substate;
58 /* 3 bits hole, try to pack */
59 unsigned char tw_rcv_wscale;
60 /* Socket demultiplex comparisons on incoming packets. */
61 /* these five are in inet_sock */
63 __u32 tw_daddr __attribute__((aligned(INET_TIMEWAIT_ADDRCMP_ALIGN_BYTES)));
67 /* And these are ours. */
69 /* 31 bits hole, try to pack */
73 struct inet_bind_bucket *tw_tb;
74 struct hlist_node tw_death_node;
77 static inline void inet_twsk_add_node(struct inet_timewait_sock *tw,
78 struct hlist_head *list)
80 hlist_add_head(&tw->tw_node, list);
83 static inline void inet_twsk_add_bind_node(struct inet_timewait_sock *tw,
84 struct hlist_head *list)
86 hlist_add_head(&tw->tw_bind_node, list);
89 static inline int inet_twsk_dead_hashed(const struct inet_timewait_sock *tw)
91 return tw->tw_death_node.pprev != NULL;
94 static inline void inet_twsk_dead_node_init(struct inet_timewait_sock *tw)
96 tw->tw_death_node.pprev = NULL;
99 static inline void __inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
101 __hlist_del(&tw->tw_death_node);
102 inet_twsk_dead_node_init(tw);
105 static inline int inet_twsk_del_dead_node(struct inet_timewait_sock *tw)
107 if (inet_twsk_dead_hashed(tw)) {
108 __inet_twsk_del_dead_node(tw);
114 #define inet_twsk_for_each(tw, node, head) \
115 hlist_for_each_entry(tw, node, head, tw_node)
117 #define inet_twsk_for_each_inmate(tw, node, jail) \
118 hlist_for_each_entry(tw, node, jail, tw_death_node)
120 #define inet_twsk_for_each_inmate_safe(tw, node, safe, jail) \
121 hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)
123 static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
125 return (struct inet_timewait_sock *)sk;
128 static inline u32 inet_rcv_saddr(const struct sock *sk)
130 return likely(sk->sk_state != TCP_TIME_WAIT) ?
131 inet_sk(sk)->rcv_saddr : inet_twsk(sk)->tw_rcv_saddr;
134 static inline void inet_twsk_put(struct inet_timewait_sock *tw)
136 if (atomic_dec_and_test(&tw->tw_refcnt)) {
137 #ifdef SOCK_REFCNT_DEBUG
138 printk(KERN_DEBUG "%s timewait_sock %p released\n",
139 tw->tw_prot->name, tw);
141 kmem_cache_free(tw->tw_prot->twsk_slab, tw);
145 extern void __inet_twsk_kill(struct inet_timewait_sock *tw,
146 struct inet_hashinfo *hashinfo);
148 extern void __inet_twsk_hashdance(struct inet_timewait_sock *tw,
150 struct inet_hashinfo *hashinfo);
151 #endif /* _INET_TIMEWAIT_SOCK_ */