netfilter: xt_qtaguid: warn only once for missing proc qtaguid data
[linux-2.6.git] / net / x25 / x25_timer.c
1 /*
2  *      X.25 Packet Layer release 002
3  *
4  *      This is ALPHA test software. This code may break your machine,
5  *      randomly fail to work with new releases, misbehave and/or generally
6  *      screw up. It might even work.
7  *
8  *      This code REQUIRES 2.1.15 or higher
9  *
10  *      This module:
11  *              This module is free software; you can redistribute it and/or
12  *              modify it under the terms of the GNU General Public License
13  *              as published by the Free Software Foundation; either version
14  *              2 of the License, or (at your option) any later version.
15  *
16  *      History
17  *      X.25 001        Jonathan Naylor Started coding.
18  *      X.25 002        Jonathan Naylor New timer architecture.
19  *                                      Centralised disconnection processing.
20  */
21
22 #include <linux/errno.h>
23 #include <linux/jiffies.h>
24 #include <linux/timer.h>
25 #include <net/sock.h>
26 #include <net/tcp_states.h>
27 #include <net/x25.h>
28
29 static void x25_heartbeat_expiry(unsigned long);
30 static void x25_timer_expiry(unsigned long);
31
32 void x25_init_timers(struct sock *sk)
33 {
34         struct x25_sock *x25 = x25_sk(sk);
35
36         setup_timer(&x25->timer, x25_timer_expiry, (unsigned long)sk);
37
38         /* initialized by sock_init_data */
39         sk->sk_timer.data     = (unsigned long)sk;
40         sk->sk_timer.function = &x25_heartbeat_expiry;
41 }
42
43 void x25_start_heartbeat(struct sock *sk)
44 {
45         mod_timer(&sk->sk_timer, jiffies + 5 * HZ);
46 }
47
48 void x25_stop_heartbeat(struct sock *sk)
49 {
50         del_timer(&sk->sk_timer);
51 }
52
53 void x25_start_t2timer(struct sock *sk)
54 {
55         struct x25_sock *x25 = x25_sk(sk);
56
57         mod_timer(&x25->timer, jiffies + x25->t2);
58 }
59
60 void x25_start_t21timer(struct sock *sk)
61 {
62         struct x25_sock *x25 = x25_sk(sk);
63
64         mod_timer(&x25->timer, jiffies + x25->t21);
65 }
66
67 void x25_start_t22timer(struct sock *sk)
68 {
69         struct x25_sock *x25 = x25_sk(sk);
70
71         mod_timer(&x25->timer, jiffies + x25->t22);
72 }
73
74 void x25_start_t23timer(struct sock *sk)
75 {
76         struct x25_sock *x25 = x25_sk(sk);
77
78         mod_timer(&x25->timer, jiffies + x25->t23);
79 }
80
81 void x25_stop_timer(struct sock *sk)
82 {
83         del_timer(&x25_sk(sk)->timer);
84 }
85
86 unsigned long x25_display_timer(struct sock *sk)
87 {
88         struct x25_sock *x25 = x25_sk(sk);
89
90         if (!timer_pending(&x25->timer))
91                 return 0;
92
93         return x25->timer.expires - jiffies;
94 }
95
96 static void x25_heartbeat_expiry(unsigned long param)
97 {
98         struct sock *sk = (struct sock *)param;
99
100         bh_lock_sock(sk);
101         if (sock_owned_by_user(sk)) /* can currently only occur in state 3 */
102                 goto restart_heartbeat;
103
104         switch (x25_sk(sk)->state) {
105
106                 case X25_STATE_0:
107                         /*
108                          * Magic here: If we listen() and a new link dies
109                          * before it is accepted() it isn't 'dead' so doesn't
110                          * get removed.
111                          */
112                         if (sock_flag(sk, SOCK_DESTROY) ||
113                             (sk->sk_state == TCP_LISTEN &&
114                              sock_flag(sk, SOCK_DEAD))) {
115                                 bh_unlock_sock(sk);
116                                 x25_destroy_socket_from_timer(sk);
117                                 return;
118                         }
119                         break;
120
121                 case X25_STATE_3:
122                         /*
123                          * Check for the state of the receive buffer.
124                          */
125                         x25_check_rbuf(sk);
126                         break;
127         }
128 restart_heartbeat:
129         x25_start_heartbeat(sk);
130         bh_unlock_sock(sk);
131 }
132
133 /*
134  *      Timer has expired, it may have been T2, T21, T22, or T23. We can tell
135  *      by the state machine state.
136  */
137 static inline void x25_do_timer_expiry(struct sock * sk)
138 {
139         struct x25_sock *x25 = x25_sk(sk);
140
141         switch (x25->state) {
142
143                 case X25_STATE_3:       /* T2 */
144                         if (x25->condition & X25_COND_ACK_PENDING) {
145                                 x25->condition &= ~X25_COND_ACK_PENDING;
146                                 x25_enquiry_response(sk);
147                         }
148                         break;
149
150                 case X25_STATE_1:       /* T21 */
151                 case X25_STATE_4:       /* T22 */
152                         x25_write_internal(sk, X25_CLEAR_REQUEST);
153                         x25->state = X25_STATE_2;
154                         x25_start_t23timer(sk);
155                         break;
156
157                 case X25_STATE_2:       /* T23 */
158                         x25_disconnect(sk, ETIMEDOUT, 0, 0);
159                         break;
160         }
161 }
162
163 static void x25_timer_expiry(unsigned long param)
164 {
165         struct sock *sk = (struct sock *)param;
166
167         bh_lock_sock(sk);
168         if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */
169                 if (x25_sk(sk)->state == X25_STATE_3)
170                         x25_start_t2timer(sk);
171         } else
172                 x25_do_timer_expiry(sk);
173         bh_unlock_sock(sk);
174 }