include/net/inet_timewait_sock.h

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