xref: /openbmc/linux/include/net/inet_timewait_sock.h (revision 26d0dfbb16fcb17d128a79dc70f3020ea6992af0)
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  
26  struct 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   */
33  struct 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_transparent  : 1,
69  				tw_flowlabel	: 20,
70  				tw_pad		: 3,	/* 3 bits hole */
71  				tw_tos		: 8;
72  	u32			tw_txhash;
73  	u32			tw_priority;
74  	struct timer_list	tw_timer;
75  	struct inet_bind_bucket	*tw_tb;
76  	struct inet_bind2_bucket	*tw_tb2;
77  	struct hlist_node		tw_bind2_node;
78  };
79  #define tw_tclass tw_tos
80  
81  #define twsk_for_each_bound_bhash2(__tw, list) \
82  	hlist_for_each_entry(__tw, list, tw_bind2_node)
83  
inet_twsk(const struct sock * sk)84  static inline struct inet_timewait_sock *inet_twsk(const struct sock *sk)
85  {
86  	return (struct inet_timewait_sock *)sk;
87  }
88  
89  void inet_twsk_free(struct inet_timewait_sock *tw);
90  void inet_twsk_put(struct inet_timewait_sock *tw);
91  
92  void inet_twsk_bind_unhash(struct inet_timewait_sock *tw,
93  			   struct inet_hashinfo *hashinfo);
94  
95  struct inet_timewait_sock *inet_twsk_alloc(const struct sock *sk,
96  					   struct inet_timewait_death_row *dr,
97  					   const int state);
98  
99  void inet_twsk_hashdance(struct inet_timewait_sock *tw, struct sock *sk,
100  			 struct inet_hashinfo *hashinfo);
101  
102  void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo,
103  			  bool rearm);
104  
inet_twsk_schedule(struct inet_timewait_sock * tw,int timeo)105  static inline void inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo)
106  {
107  	__inet_twsk_schedule(tw, timeo, false);
108  }
109  
inet_twsk_reschedule(struct inet_timewait_sock * tw,int timeo)110  static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo)
111  {
112  	__inet_twsk_schedule(tw, timeo, true);
113  }
114  
115  void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
116  
117  void inet_twsk_purge(struct inet_hashinfo *hashinfo);
118  
119  static inline
twsk_net(const struct inet_timewait_sock * twsk)120  struct net *twsk_net(const struct inet_timewait_sock *twsk)
121  {
122  	return read_pnet(&twsk->tw_net);
123  }
124  
125  static inline
twsk_net_set(struct inet_timewait_sock * twsk,struct net * net)126  void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net)
127  {
128  	write_pnet(&twsk->tw_net, net);
129  }
130  #endif	/* _INET_TIMEWAIT_SOCK_ */
131