LXR linux/include/net/inet_timewait

   1/*
   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.
   5 *
   6 *              Definitions for a generic INET TIMEWAIT sock
   7 *
   8 *              From code originally in net/tcp.h
   9 *
  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.
  14 */
  15#ifndef _INET_TIMEWAIT_SOCK_
  16#define _INET_TIMEWAIT_SOCK_
  17
  18
  19#include <linux/kmemcheck.h>
  20#include <linux/list.h>
  21#include <linux/timer.h>
  22#include <linux/types.h>
  23#include <linux/workqueue.h>
  24
  25#include <net/inet_sock.h>
  26#include <net/sock.h>
  27#include <net/tcp_states.h>
  28#include <net/timewait_sock.h>
  29
  30#include <linux/atomic.h>
  31
  32struct inet_hashinfo;
  33
  34struct inet_timewait_death_row {
  35        atomic_t                tw_count;
  36
  37        struct inet_hashinfo    *hashinfo ____cacheline_aligned_in_smp;
  38        int                     sysctl_tw_recycle;
  39        int                     sysctl_max_tw_buckets;
  40};
  41
  42struct inet_bind_bucket;
  43
  44/*
  45 * This is a TIME_WAIT sock. It works around the memory consumption
  46 * problems of sockets in such a state on heavily loaded servers, but
  47 * without violating the protocol specification.
  48 */
  49struct inet_timewait_sock {
  50        /*
  51         * Now struct sock also uses sock_common, so please just
  52         * don't add nothing before this first member (__tw_common) --acme
  53         */
  54        struct sock_common      __tw_common;
  55#define tw_family               __tw_common.skc_family
  56#define tw_state                __tw_common.skc_state
  57#define tw_reuse                __tw_common.skc_reuse
  58#define tw_ipv6only             __tw_common.skc_ipv6only
  59#define tw_bound_dev_if         __tw_common.skc_bound_dev_if
  60#define tw_node                 __tw_common.skc_nulls_node
  61#define tw_bind_node            __tw_common.skc_bind_node
  62#define tw_refcnt               __tw_common.skc_refcnt
  63#define tw_hash                 __tw_common.skc_hash
  64#define tw_prot                 __tw_common.skc_prot
  65#define tw_net                  __tw_common.skc_net
  66#define tw_daddr                __tw_common.skc_daddr
  67#define tw_v6_daddr             __tw_common.skc_v6_daddr
  68#define tw_rcv_saddr            __tw_common.skc_rcv_saddr
  69#define tw_v6_rcv_saddr         __tw_common.skc_v6_rcv_saddr
  70#define tw_dport                __tw_common.skc_dport
  71#define tw_num                  __tw_common.skc_num
  72#define tw_cookie               __tw_common.skc_cookie
  73
  74        int                     tw_timeout;
  75        volatile unsigned char  tw_substate;
  76        unsigned char           tw_rcv_wscale;
  77
  78        /* Socket demultiplex comparisons on incoming packets. */
  79        /* these three are in inet_sock */
  80        __be16                  tw_sport;
  81        kmemcheck_bitfield_begin(flags);
  82        /* And these are ours. */
  83        unsigned int            tw_kill         : 1,
  84                                tw_transparent  : 1,
  85                                tw_flowlabel    : 20,
  86                                tw_pad          : 2,    /* 2 bits hole */
  87                                tw_tos          : 8;
  88        kmemcheck_bitfield_end(flags);
  89        struct timer_list       tw_timer;
  90        struct inet_bind_bucket *tw_tb;
  91        struct inet_timewait_death_row *tw_dr;
  92};
  93#define tw_tclass tw_tos
  94
  95static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
  96{
  97        return (struct inet_timewait_sock *)sk;
  98}
  99
 100void inet_twsk_free(struct inet_timewait_sock *tw);
 101void inet_twsk_put(struct inet_timewait_sock *tw);
 102
 103void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
 104                           struct inet_hashinfo *hashinfo);
 105
 106struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
 107                                           struct inet_timewait_death_row *dr,
 108                                           const int state);
 109
 110void __inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
 111                           struct inet_hashinfo *hashinfo);
 112
 113void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
 114                          bool rearm);
 115
 116static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
 117{
 118        __inet_twsk_schedule(tw, timeo, false);
 119}
 120
 121static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
 122{
 123        __inet_twsk_schedule(tw, timeo, true);
 124}
 125
 126void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
 127
 128void inet_twsk_purge(struct inet_hashinfo *hashinfo,
 129                     struct inet_timewait_death_row *twdr, int family);
 130
 131static inline
 132struct net *twsk_net(const struct inet_timewait_sock *twsk)
 133{
 134        return read_pnet(&twsk->tw_net);
 135}
 136
 137static inline
 138void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
 139{
 140        write_pnet(&twsk->tw_net, net);
 141}
 142#endif  /* _INET_TIMEWAIT_SOCK_ */
 143