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-rw-r--r--net/x25/x25_timer.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/net/x25/x25_timer.c b/net/x25/x25_timer.c
new file mode 100644
index 000000000..5c5db1a36
--- /dev/null
+++ b/net/x25/x25_timer.c
@@ -0,0 +1,174 @@
+/*
+ * X.25 Packet Layer release 002
+ *
+ * This is ALPHA test software. This code may break your machine,
+ * randomly fail to work with new releases, misbehave and/or generally
+ * screw up. It might even work.
+ *
+ * This code REQUIRES 2.1.15 or higher
+ *
+ * This module:
+ * This module is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * History
+ * X.25 001 Jonathan Naylor Started coding.
+ * X.25 002 Jonathan Naylor New timer architecture.
+ * Centralised disconnection processing.
+ */
+
+#include <linux/errno.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <net/x25.h>
+
+static void x25_heartbeat_expiry(unsigned long);
+static void x25_timer_expiry(unsigned long);
+
+void x25_init_timers(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ setup_timer(&x25->timer, x25_timer_expiry, (unsigned long)sk);
+
+ /* initialized by sock_init_data */
+ sk->sk_timer.data = (unsigned long)sk;
+ sk->sk_timer.function = &x25_heartbeat_expiry;
+}
+
+void x25_start_heartbeat(struct sock *sk)
+{
+ mod_timer(&sk->sk_timer, jiffies + 5 * HZ);
+}
+
+void x25_stop_heartbeat(struct sock *sk)
+{
+ del_timer(&sk->sk_timer);
+}
+
+void x25_start_t2timer(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ mod_timer(&x25->timer, jiffies + x25->t2);
+}
+
+void x25_start_t21timer(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ mod_timer(&x25->timer, jiffies + x25->t21);
+}
+
+void x25_start_t22timer(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ mod_timer(&x25->timer, jiffies + x25->t22);
+}
+
+void x25_start_t23timer(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ mod_timer(&x25->timer, jiffies + x25->t23);
+}
+
+void x25_stop_timer(struct sock *sk)
+{
+ del_timer(&x25_sk(sk)->timer);
+}
+
+unsigned long x25_display_timer(struct sock *sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ if (!timer_pending(&x25->timer))
+ return 0;
+
+ return x25->timer.expires - jiffies;
+}
+
+static void x25_heartbeat_expiry(unsigned long param)
+{
+ struct sock *sk = (struct sock *)param;
+
+ bh_lock_sock(sk);
+ if (sock_owned_by_user(sk)) /* can currently only occur in state 3 */
+ goto restart_heartbeat;
+
+ switch (x25_sk(sk)->state) {
+
+ case X25_STATE_0:
+ /*
+ * Magic here: If we listen() and a new link dies
+ * before it is accepted() it isn't 'dead' so doesn't
+ * get removed.
+ */
+ if (sock_flag(sk, SOCK_DESTROY) ||
+ (sk->sk_state == TCP_LISTEN &&
+ sock_flag(sk, SOCK_DEAD))) {
+ bh_unlock_sock(sk);
+ x25_destroy_socket_from_timer(sk);
+ return;
+ }
+ break;
+
+ case X25_STATE_3:
+ /*
+ * Check for the state of the receive buffer.
+ */
+ x25_check_rbuf(sk);
+ break;
+ }
+restart_heartbeat:
+ x25_start_heartbeat(sk);
+ bh_unlock_sock(sk);
+}
+
+/*
+ * Timer has expired, it may have been T2, T21, T22, or T23. We can tell
+ * by the state machine state.
+ */
+static inline void x25_do_timer_expiry(struct sock * sk)
+{
+ struct x25_sock *x25 = x25_sk(sk);
+
+ switch (x25->state) {
+
+ case X25_STATE_3: /* T2 */
+ if (x25->condition & X25_COND_ACK_PENDING) {
+ x25->condition &= ~X25_COND_ACK_PENDING;
+ x25_enquiry_response(sk);
+ }
+ break;
+
+ case X25_STATE_1: /* T21 */
+ case X25_STATE_4: /* T22 */
+ x25_write_internal(sk, X25_CLEAR_REQUEST);
+ x25->state = X25_STATE_2;
+ x25_start_t23timer(sk);
+ break;
+
+ case X25_STATE_2: /* T23 */
+ x25_disconnect(sk, ETIMEDOUT, 0, 0);
+ break;
+ }
+}
+
+static void x25_timer_expiry(unsigned long param)
+{
+ struct sock *sk = (struct sock *)param;
+
+ bh_lock_sock(sk);
+ if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */
+ if (x25_sk(sk)->state == X25_STATE_3)
+ x25_start_t2timer(sk);
+ } else
+ x25_do_timer_expiry(sk);
+ bh_unlock_sock(sk);
+}