1 files changed, 176 insertions, 0 deletions

diff --git a/net/x25/x25_timer.c b/net/x25/x25_timer.c
new file mode 100644
index 000000000000..d6a21a3ad80e
--- /dev/null
+++ b/net/x25/x25_timer.c
@@ -0,0 +1,176 @@
+/*
+ *      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.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);
+
+        init_timer(&x25->timer);
+        x25->timer.data     = (unsigned long)sk;
+        x25->timer.function = &x25_timer_expiry;
+
+        /* 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))) {
+                                x25_destroy_socket(sk);
+                                goto unlock;
+                        }
+                        break;
+
+                case X25_STATE_3:
+                        /*
+                         * Check for the state of the receive buffer.
+                         */
+                        x25_check_rbuf(sk);
+                        break;
+        }
+restart_heartbeat:
+        x25_start_heartbeat(sk);
+unlock:
+        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);
+}