1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org)
6 */
7#include <linux/errno.h>
8#include <linux/types.h>
9#include <linux/socket.h>
10#include <linux/in.h>
11#include <linux/kernel.h>
12#include <linux/jiffies.h>
13#include <linux/timer.h>
14#include <linux/string.h>
15#include <linux/sockios.h>
16#include <linux/net.h>
17#include <net/ax25.h>
18#include <linux/inet.h>
19#include <linux/netdevice.h>
20#include <linux/skbuff.h>
21#include <net/sock.h>
22#include <net/tcp_states.h>
23#include <linux/uaccess.h>
24#include <linux/fcntl.h>
25#include <linux/mm.h>
26#include <linux/interrupt.h>
27#include <net/netrom.h>
28
29static void nr_heartbeat_expiry(struct timer_list *);
30static void nr_t1timer_expiry(struct timer_list *);
31static void nr_t2timer_expiry(struct timer_list *);
32static void nr_t4timer_expiry(struct timer_list *);
33static void nr_idletimer_expiry(struct timer_list *);
34
35void nr_init_timers(struct sock *sk)
36{
37 struct nr_sock *nr = nr_sk(sk);
38
39 timer_setup(&nr->t1timer, nr_t1timer_expiry, 0);
40 timer_setup(&nr->t2timer, nr_t2timer_expiry, 0);
41 timer_setup(&nr->t4timer, nr_t4timer_expiry, 0);
42 timer_setup(&nr->idletimer, nr_idletimer_expiry, 0);
43
44 /* initialized by sock_init_data */
45 sk->sk_timer.function = nr_heartbeat_expiry;
46}
47
48void nr_start_t1timer(struct sock *sk)
49{
50 struct nr_sock *nr = nr_sk(sk);
51
52 sk_reset_timer(sk, timer: &nr->t1timer, expires: jiffies + nr->t1);
53}
54
55void nr_start_t2timer(struct sock *sk)
56{
57 struct nr_sock *nr = nr_sk(sk);
58
59 sk_reset_timer(sk, timer: &nr->t2timer, expires: jiffies + nr->t2);
60}
61
62void nr_start_t4timer(struct sock *sk)
63{
64 struct nr_sock *nr = nr_sk(sk);
65
66 sk_reset_timer(sk, timer: &nr->t4timer, expires: jiffies + nr->t4);
67}
68
69void nr_start_idletimer(struct sock *sk)
70{
71 struct nr_sock *nr = nr_sk(sk);
72
73 if (nr->idle > 0)
74 sk_reset_timer(sk, timer: &nr->idletimer, expires: jiffies + nr->idle);
75}
76
77void nr_start_heartbeat(struct sock *sk)
78{
79 sk_reset_timer(sk, timer: &sk->sk_timer, expires: jiffies + 5 * HZ);
80}
81
82void nr_stop_t1timer(struct sock *sk)
83{
84 sk_stop_timer(sk, timer: &nr_sk(sk)->t1timer);
85}
86
87void nr_stop_t2timer(struct sock *sk)
88{
89 sk_stop_timer(sk, timer: &nr_sk(sk)->t2timer);
90}
91
92void nr_stop_t4timer(struct sock *sk)
93{
94 sk_stop_timer(sk, timer: &nr_sk(sk)->t4timer);
95}
96
97void nr_stop_idletimer(struct sock *sk)
98{
99 sk_stop_timer(sk, timer: &nr_sk(sk)->idletimer);
100}
101
102void nr_stop_heartbeat(struct sock *sk)
103{
104 sk_stop_timer(sk, timer: &sk->sk_timer);
105}
106
107int nr_t1timer_running(struct sock *sk)
108{
109 return timer_pending(timer: &nr_sk(sk)->t1timer);
110}
111
112static void nr_heartbeat_expiry(struct timer_list *t)
113{
114 struct sock *sk = from_timer(sk, t, sk_timer);
115 struct nr_sock *nr = nr_sk(sk);
116
117 bh_lock_sock(sk);
118 switch (nr->state) {
119 case NR_STATE_0:
120 /* Magic here: If we listen() and a new link dies before it
121 is accepted() it isn't 'dead' so doesn't get removed. */
122 if (sock_flag(sk, flag: SOCK_DESTROY) ||
123 (sk->sk_state == TCP_LISTEN && sock_flag(sk, flag: SOCK_DEAD))) {
124 sock_hold(sk);
125 bh_unlock_sock(sk);
126 nr_destroy_socket(sk);
127 goto out;
128 }
129 break;
130
131 case NR_STATE_3:
132 /*
133 * Check for the state of the receive buffer.
134 */
135 if (atomic_read(v: &sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
136 (nr->condition & NR_COND_OWN_RX_BUSY)) {
137 nr->condition &= ~NR_COND_OWN_RX_BUSY;
138 nr->condition &= ~NR_COND_ACK_PENDING;
139 nr->vl = nr->vr;
140 nr_write_internal(sk, NR_INFOACK);
141 break;
142 }
143 break;
144 }
145
146 nr_start_heartbeat(sk);
147 bh_unlock_sock(sk);
148out:
149 sock_put(sk);
150}
151
152static void nr_t2timer_expiry(struct timer_list *t)
153{
154 struct nr_sock *nr = from_timer(nr, t, t2timer);
155 struct sock *sk = &nr->sock;
156
157 bh_lock_sock(sk);
158 if (nr->condition & NR_COND_ACK_PENDING) {
159 nr->condition &= ~NR_COND_ACK_PENDING;
160 nr_enquiry_response(sk);
161 }
162 bh_unlock_sock(sk);
163 sock_put(sk);
164}
165
166static void nr_t4timer_expiry(struct timer_list *t)
167{
168 struct nr_sock *nr = from_timer(nr, t, t4timer);
169 struct sock *sk = &nr->sock;
170
171 bh_lock_sock(sk);
172 nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY;
173 bh_unlock_sock(sk);
174 sock_put(sk);
175}
176
177static void nr_idletimer_expiry(struct timer_list *t)
178{
179 struct nr_sock *nr = from_timer(nr, t, idletimer);
180 struct sock *sk = &nr->sock;
181
182 bh_lock_sock(sk);
183
184 nr_clear_queues(sk);
185
186 nr->n2count = 0;
187 nr_write_internal(sk, NR_DISCREQ);
188 nr->state = NR_STATE_2;
189
190 nr_start_t1timer(sk);
191 nr_stop_t2timer(sk);
192 nr_stop_t4timer(sk);
193
194 sk->sk_state = TCP_CLOSE;
195 sk->sk_err = 0;
196 sk->sk_shutdown |= SEND_SHUTDOWN;
197
198 if (!sock_flag(sk, flag: SOCK_DEAD)) {
199 sk->sk_state_change(sk);
200 sock_set_flag(sk, flag: SOCK_DEAD);
201 }
202 bh_unlock_sock(sk);
203 sock_put(sk);
204}
205
206static void nr_t1timer_expiry(struct timer_list *t)
207{
208 struct nr_sock *nr = from_timer(nr, t, t1timer);
209 struct sock *sk = &nr->sock;
210
211 bh_lock_sock(sk);
212 switch (nr->state) {
213 case NR_STATE_1:
214 if (nr->n2count == nr->n2) {
215 nr_disconnect(sk, ETIMEDOUT);
216 goto out;
217 } else {
218 nr->n2count++;
219 nr_write_internal(sk, NR_CONNREQ);
220 }
221 break;
222
223 case NR_STATE_2:
224 if (nr->n2count == nr->n2) {
225 nr_disconnect(sk, ETIMEDOUT);
226 goto out;
227 } else {
228 nr->n2count++;
229 nr_write_internal(sk, NR_DISCREQ);
230 }
231 break;
232
233 case NR_STATE_3:
234 if (nr->n2count == nr->n2) {
235 nr_disconnect(sk, ETIMEDOUT);
236 goto out;
237 } else {
238 nr->n2count++;
239 nr_requeue_frames(sk);
240 }
241 break;
242 }
243
244 nr_start_t1timer(sk);
245out:
246 bh_unlock_sock(sk);
247 sock_put(sk);
248}
249

source code of linux/net/netrom/nr_timer.c