xref: /openbmc/linux/net/rose/rose_timer.c (revision f3539c12)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License as published by
4  * the Free Software Foundation; either version 2 of the License, or
5  * (at your option) any later version.
6  *
7  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8  * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org)
9  */
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/in.h>
14 #include <linux/kernel.h>
15 #include <linux/jiffies.h>
16 #include <linux/timer.h>
17 #include <linux/string.h>
18 #include <linux/sockios.h>
19 #include <linux/net.h>
20 #include <net/ax25.h>
21 #include <linux/inet.h>
22 #include <linux/netdevice.h>
23 #include <linux/skbuff.h>
24 #include <net/sock.h>
25 #include <net/tcp_states.h>
26 #include <linux/fcntl.h>
27 #include <linux/mm.h>
28 #include <linux/interrupt.h>
29 #include <net/rose.h>
30 
31 static void rose_heartbeat_expiry(unsigned long);
32 static void rose_timer_expiry(unsigned long);
33 static void rose_idletimer_expiry(unsigned long);
34 
35 void rose_start_heartbeat(struct sock *sk)
36 {
37 	del_timer(&sk->sk_timer);
38 
39 	sk->sk_timer.data     = (unsigned long)sk;
40 	sk->sk_timer.function = &rose_heartbeat_expiry;
41 	sk->sk_timer.expires  = jiffies + 5 * HZ;
42 
43 	add_timer(&sk->sk_timer);
44 }
45 
46 void rose_start_t1timer(struct sock *sk)
47 {
48 	struct rose_sock *rose = rose_sk(sk);
49 
50 	del_timer(&rose->timer);
51 
52 	rose->timer.data     = (unsigned long)sk;
53 	rose->timer.function = &rose_timer_expiry;
54 	rose->timer.expires  = jiffies + rose->t1;
55 
56 	add_timer(&rose->timer);
57 }
58 
59 void rose_start_t2timer(struct sock *sk)
60 {
61 	struct rose_sock *rose = rose_sk(sk);
62 
63 	del_timer(&rose->timer);
64 
65 	rose->timer.data     = (unsigned long)sk;
66 	rose->timer.function = &rose_timer_expiry;
67 	rose->timer.expires  = jiffies + rose->t2;
68 
69 	add_timer(&rose->timer);
70 }
71 
72 void rose_start_t3timer(struct sock *sk)
73 {
74 	struct rose_sock *rose = rose_sk(sk);
75 
76 	del_timer(&rose->timer);
77 
78 	rose->timer.data     = (unsigned long)sk;
79 	rose->timer.function = &rose_timer_expiry;
80 	rose->timer.expires  = jiffies + rose->t3;
81 
82 	add_timer(&rose->timer);
83 }
84 
85 void rose_start_hbtimer(struct sock *sk)
86 {
87 	struct rose_sock *rose = rose_sk(sk);
88 
89 	del_timer(&rose->timer);
90 
91 	rose->timer.data     = (unsigned long)sk;
92 	rose->timer.function = &rose_timer_expiry;
93 	rose->timer.expires  = jiffies + rose->hb;
94 
95 	add_timer(&rose->timer);
96 }
97 
98 void rose_start_idletimer(struct sock *sk)
99 {
100 	struct rose_sock *rose = rose_sk(sk);
101 
102 	del_timer(&rose->idletimer);
103 
104 	if (rose->idle > 0) {
105 		rose->idletimer.data     = (unsigned long)sk;
106 		rose->idletimer.function = &rose_idletimer_expiry;
107 		rose->idletimer.expires  = jiffies + rose->idle;
108 
109 		add_timer(&rose->idletimer);
110 	}
111 }
112 
113 void rose_stop_heartbeat(struct sock *sk)
114 {
115 	del_timer(&sk->sk_timer);
116 }
117 
118 void rose_stop_timer(struct sock *sk)
119 {
120 	del_timer(&rose_sk(sk)->timer);
121 }
122 
123 void rose_stop_idletimer(struct sock *sk)
124 {
125 	del_timer(&rose_sk(sk)->idletimer);
126 }
127 
128 static void rose_heartbeat_expiry(unsigned long param)
129 {
130 	struct sock *sk = (struct sock *)param;
131 	struct rose_sock *rose = rose_sk(sk);
132 
133 	bh_lock_sock(sk);
134 	switch (rose->state) {
135 	case ROSE_STATE_0:
136 		/* Magic here: If we listen() and a new link dies before it
137 		   is accepted() it isn't 'dead' so doesn't get removed. */
138 		if (sock_flag(sk, SOCK_DESTROY) ||
139 		    (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) {
140 			bh_unlock_sock(sk);
141 			rose_destroy_socket(sk);
142 			return;
143 		}
144 		break;
145 
146 	case ROSE_STATE_3:
147 		/*
148 		 * Check for the state of the receive buffer.
149 		 */
150 		if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
151 		    (rose->condition & ROSE_COND_OWN_RX_BUSY)) {
152 			rose->condition &= ~ROSE_COND_OWN_RX_BUSY;
153 			rose->condition &= ~ROSE_COND_ACK_PENDING;
154 			rose->vl         = rose->vr;
155 			rose_write_internal(sk, ROSE_RR);
156 			rose_stop_timer(sk);	/* HB */
157 			break;
158 		}
159 		break;
160 	}
161 
162 	rose_start_heartbeat(sk);
163 	bh_unlock_sock(sk);
164 }
165 
166 static void rose_timer_expiry(unsigned long param)
167 {
168 	struct sock *sk = (struct sock *)param;
169 	struct rose_sock *rose = rose_sk(sk);
170 
171 	bh_lock_sock(sk);
172 	switch (rose->state) {
173 	case ROSE_STATE_1:	/* T1 */
174 	case ROSE_STATE_4:	/* T2 */
175 		rose_write_internal(sk, ROSE_CLEAR_REQUEST);
176 		rose->state = ROSE_STATE_2;
177 		rose_start_t3timer(sk);
178 		break;
179 
180 	case ROSE_STATE_2:	/* T3 */
181 		rose->neighbour->use--;
182 		rose_disconnect(sk, ETIMEDOUT, -1, -1);
183 		break;
184 
185 	case ROSE_STATE_3:	/* HB */
186 		if (rose->condition & ROSE_COND_ACK_PENDING) {
187 			rose->condition &= ~ROSE_COND_ACK_PENDING;
188 			rose_enquiry_response(sk);
189 		}
190 		break;
191 	}
192 	bh_unlock_sock(sk);
193 }
194 
195 static void rose_idletimer_expiry(unsigned long param)
196 {
197 	struct sock *sk = (struct sock *)param;
198 
199 	bh_lock_sock(sk);
200 	rose_clear_queues(sk);
201 
202 	rose_write_internal(sk, ROSE_CLEAR_REQUEST);
203 	rose_sk(sk)->state = ROSE_STATE_2;
204 
205 	rose_start_t3timer(sk);
206 
207 	sk->sk_state     = TCP_CLOSE;
208 	sk->sk_err       = 0;
209 	sk->sk_shutdown |= SEND_SHUTDOWN;
210 
211 	if (!sock_flag(sk, SOCK_DEAD)) {
212 		sk->sk_state_change(sk);
213 		sock_set_flag(sk, SOCK_DEAD);
214 	}
215 	bh_unlock_sock(sk);
216 }
217