[PATCH] V4L/DVB (4045): Fixes recursive dependency for I2C
[linux-2.6/kvm.git] / net / ax25 / ax25_ds_timer.c
blob5961459935eb4f0d13497b4b6b0ecda79f7ca6dc
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.
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de)
9 */
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/spinlock.h>
14 #include <linux/in.h>
15 #include <linux/kernel.h>
16 #include <linux/jiffies.h>
17 #include <linux/timer.h>
18 #include <linux/string.h>
19 #include <linux/sockios.h>
20 #include <linux/net.h>
21 #include <net/tcp_states.h>
22 #include <net/ax25.h>
23 #include <linux/inet.h>
24 #include <linux/netdevice.h>
25 #include <linux/skbuff.h>
26 #include <net/sock.h>
27 #include <asm/uaccess.h>
28 #include <asm/system.h>
29 #include <linux/fcntl.h>
30 #include <linux/mm.h>
31 #include <linux/interrupt.h>
33 static void ax25_ds_timeout(unsigned long);
36 * Add DAMA slave timeout timer to timer list.
37 * Unlike the connection based timers the timeout function gets
38 * triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
39 * (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
40 * 1/10th of a second.
43 static void ax25_ds_add_timer(ax25_dev *ax25_dev)
45 struct timer_list *t = &ax25_dev->dama.slave_timer;
46 t->data = (unsigned long) ax25_dev;
47 t->function = &ax25_ds_timeout;
48 t->expires = jiffies + HZ;
49 add_timer(t);
52 void ax25_ds_del_timer(ax25_dev *ax25_dev)
54 if (ax25_dev)
55 del_timer(&ax25_dev->dama.slave_timer);
58 void ax25_ds_set_timer(ax25_dev *ax25_dev)
60 if (ax25_dev == NULL) /* paranoia */
61 return;
63 del_timer(&ax25_dev->dama.slave_timer);
64 ax25_dev->dama.slave_timeout =
65 msecs_to_jiffies(ax25_dev->values[AX25_VALUES_DS_TIMEOUT]) / 10;
66 ax25_ds_add_timer(ax25_dev);
70 * DAMA Slave Timeout
71 * Silently discard all (slave) connections in case our master forgot us...
74 static void ax25_ds_timeout(unsigned long arg)
76 ax25_dev *ax25_dev = (struct ax25_dev *) arg;
77 ax25_cb *ax25;
78 struct hlist_node *node;
80 if (ax25_dev == NULL || !ax25_dev->dama.slave)
81 return; /* Yikes! */
83 if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) {
84 ax25_ds_set_timer(ax25_dev);
85 return;
88 spin_lock_bh(&ax25_list_lock);
89 ax25_for_each(ax25, node, &ax25_list) {
90 if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
91 continue;
93 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
94 ax25_disconnect(ax25, ETIMEDOUT);
96 spin_unlock_bh(&ax25_list_lock);
98 ax25_dev_dama_off(ax25_dev);
101 void ax25_ds_heartbeat_expiry(ax25_cb *ax25)
103 struct sock *sk=ax25->sk;
105 if (sk)
106 bh_lock_sock(sk);
108 switch (ax25->state) {
110 case AX25_STATE_0:
111 /* Magic here: If we listen() and a new link dies before it
112 is accepted() it isn't 'dead' so doesn't get removed. */
113 if (!sk || sock_flag(sk, SOCK_DESTROY) ||
114 (sk->sk_state == TCP_LISTEN &&
115 sock_flag(sk, SOCK_DEAD))) {
116 if (sk) {
117 sock_hold(sk);
118 ax25_destroy_socket(ax25);
119 sock_put(sk);
120 bh_unlock_sock(sk);
121 } else
122 ax25_destroy_socket(ax25);
123 return;
125 break;
127 case AX25_STATE_3:
129 * Check the state of the receive buffer.
131 if (sk != NULL) {
132 if (atomic_read(&sk->sk_rmem_alloc) <
133 (sk->sk_rcvbuf / 2) &&
134 (ax25->condition & AX25_COND_OWN_RX_BUSY)) {
135 ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
136 ax25->condition &= ~AX25_COND_ACK_PENDING;
137 break;
140 break;
143 if (sk)
144 bh_unlock_sock(sk);
146 ax25_start_heartbeat(ax25);
149 /* dl1bke 960114: T3 works much like the IDLE timeout, but
150 * gets reloaded with every frame for this
151 * connection.
153 void ax25_ds_t3timer_expiry(ax25_cb *ax25)
155 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
156 ax25_dama_off(ax25);
157 ax25_disconnect(ax25, ETIMEDOUT);
160 /* dl1bke 960228: close the connection when IDLE expires.
161 * unlike T3 this timer gets reloaded only on
162 * I frames.
164 void ax25_ds_idletimer_expiry(ax25_cb *ax25)
166 ax25_clear_queues(ax25);
168 ax25->n2count = 0;
169 ax25->state = AX25_STATE_2;
171 ax25_calculate_t1(ax25);
172 ax25_start_t1timer(ax25);
173 ax25_stop_t3timer(ax25);
175 if (ax25->sk != NULL) {
176 bh_lock_sock(ax25->sk);
177 ax25->sk->sk_state = TCP_CLOSE;
178 ax25->sk->sk_err = 0;
179 ax25->sk->sk_shutdown |= SEND_SHUTDOWN;
180 if (!sock_flag(ax25->sk, SOCK_DEAD)) {
181 ax25->sk->sk_state_change(ax25->sk);
182 sock_set_flag(ax25->sk, SOCK_DEAD);
184 bh_unlock_sock(ax25->sk);
188 /* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
189 * within the poll of any connected channel. Remember
190 * that we are not allowed to send anything unless we
191 * get polled by the Master.
193 * Thus we'll have to do parts of our T1 handling in
194 * ax25_enquiry_response().
196 void ax25_ds_t1_timeout(ax25_cb *ax25)
198 switch (ax25->state) {
199 case AX25_STATE_1:
200 if (ax25->n2count == ax25->n2) {
201 if (ax25->modulus == AX25_MODULUS) {
202 ax25_disconnect(ax25, ETIMEDOUT);
203 return;
204 } else {
205 ax25->modulus = AX25_MODULUS;
206 ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
207 ax25->n2count = 0;
208 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
210 } else {
211 ax25->n2count++;
212 if (ax25->modulus == AX25_MODULUS)
213 ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
214 else
215 ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
217 break;
219 case AX25_STATE_2:
220 if (ax25->n2count == ax25->n2) {
221 ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
222 ax25_disconnect(ax25, ETIMEDOUT);
223 return;
224 } else {
225 ax25->n2count++;
227 break;
229 case AX25_STATE_3:
230 if (ax25->n2count == ax25->n2) {
231 ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
232 ax25_disconnect(ax25, ETIMEDOUT);
233 return;
234 } else {
235 ax25->n2count++;
237 break;
240 ax25_calculate_t1(ax25);
241 ax25_start_t1timer(ax25);