LXR linux/include/net/inet_timewait

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * INET         An implementation of the TCP/IP protocol suite for the LINUX
   4 *              operating system.  INET is implemented using the  BSD Socket
   5 *              interface as the means of communication with the user level.
   6 *
   7 *              Definitions for a generic INET TIMEWAIT sock
   8 *
   9 *              From code originally in net/tcp.h
  10 */
  11#ifndef _INET_TIMEWAIT_SOCK_
  12#define _INET_TIMEWAIT_SOCK_
  13
  14#include <linux/list.h>
  15#include <linux/timer.h>
  16#include <linux/types.h>
  17#include <linux/workqueue.h>
  18
  19#include <net/inet_sock.h>
  20#include <net/sock.h>
  21#include <net/tcp_states.h>
  22#include <net/timewait_sock.h>
  23
  24#include <linux/atomic.h>
  25
  26struct inet_bind_bucket;
  27
  28/*
  29 * This is a TIME_WAIT sock. It works around the memory consumption
  30 * problems of sockets in such a state on heavily loaded servers, but
  31 * without violating the protocol specification.
  32 */
  33struct inet_timewait_sock {
  34        /*
  35         * Now struct sock also uses sock_common, so please just
  36         * don't add nothing before this first member (__tw_common) --acme
  37         */
  38        struct sock_common      __tw_common;
  39#define tw_family               __tw_common.skc_family
  40#define tw_state                __tw_common.skc_state
  41#define tw_reuse                __tw_common.skc_reuse
  42#define tw_reuseport            __tw_common.skc_reuseport
  43#define tw_ipv6only             __tw_common.skc_ipv6only
  44#define tw_bound_dev_if         __tw_common.skc_bound_dev_if
  45#define tw_node                 __tw_common.skc_nulls_node
  46#define tw_bind_node            __tw_common.skc_bind_node
  47#define tw_refcnt               __tw_common.skc_refcnt
  48#define tw_hash                 __tw_common.skc_hash
  49#define tw_prot                 __tw_common.skc_prot
  50#define tw_net                  __tw_common.skc_net
  51#define tw_daddr                __tw_common.skc_daddr
  52#define tw_v6_daddr             __tw_common.skc_v6_daddr
  53#define tw_rcv_saddr            __tw_common.skc_rcv_saddr
  54#define tw_v6_rcv_saddr         __tw_common.skc_v6_rcv_saddr
  55#define tw_dport                __tw_common.skc_dport
  56#define tw_num                  __tw_common.skc_num
  57#define tw_cookie               __tw_common.skc_cookie
  58#define tw_dr                   __tw_common.skc_tw_dr
  59
  60        __u32                   tw_mark;
  61        volatile unsigned char  tw_substate;
  62        unsigned char           tw_rcv_wscale;
  63
  64        /* Socket demultiplex comparisons on incoming packets. */
  65        /* these three are in inet_sock */
  66        __be16                  tw_sport;
  67        /* And these are ours. */
  68        unsigned int            tw_kill         : 1,
  69                                tw_transparent  : 1,
  70                                tw_flowlabel    : 20,
  71                                tw_pad          : 2,    /* 2 bits hole */
  72                                tw_tos          : 8;
  73        u32                     tw_txhash;
  74        u32                     tw_priority;
  75        struct timer_list       tw_timer;
  76        struct inet_bind_bucket *tw_tb;
  77};
  78#define tw_tclass tw_tos
  79
  80static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
  81{
  82        return (struct inet_timewait_sock *)sk;
  83}
  84
  85void inet_twsk_free(struct inet_timewait_sock *tw);
  86void inet_twsk_put(struct inet_timewait_sock *tw);
  87
  88void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
  89                           struct inet_hashinfo *hashinfo);
  90
  91struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
  92                                           struct inet_timewait_death_row *dr,
  93                                           const int state);
  94
  95void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
  96                         struct inet_hashinfo *hashinfo);
  97
  98void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
  99                          bool rearm);
 100
 101static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
 102{
 103        __inet_twsk_schedule(tw, timeo, false);
 104}
 105
 106static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
 107{
 108        __inet_twsk_schedule(tw, timeo, true);
 109}
 110
 111void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
 112
 113void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
 114
 115static inline
 116struct net *twsk_net(const struct inet_timewait_sock *twsk)
 117{
 118        return read_pnet(&twsk->tw_net);
 119}
 120
 121static inline
 122void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
 123{
 124        write_pnet(&twsk->tw_net, net);
 125}
 126#endif  /* _INET_TIMEWAIT_SOCK_ */
 127