diff options
Diffstat (limited to 'net/x25/x25_timer.c')
| -rw-r--r-- | net/x25/x25_timer.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/net/x25/x25_timer.c b/net/x25/x25_timer.c new file mode 100644 index 000000000..e625c41ed --- /dev/null +++ b/net/x25/x25_timer.c @@ -0,0 +1,145 @@ +/* + * X.25 Packet Layer release 001 + * + * 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. + */ + +#include <linux/config.h> +#if defined(CONFIG_X25) || defined(CONFIG_X25_MODULE) +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <asm/segment.h> +#include <asm/system.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/x25.h> + +static void x25_timer(unsigned long); + +/* + * Linux set timer + */ +void x25_set_timer(struct sock *sk) +{ + unsigned long flags; + + save_flags(flags); cli(); + del_timer(&sk->timer); + restore_flags(flags); + + sk->timer.data = (unsigned long)sk; + sk->timer.function = &x25_timer; + sk->timer.expires = jiffies + (HZ / 1); + + add_timer(&sk->timer); +} + +/* + * X.25 TIMER + * + * This routine is called every second. Decrement timer by this + * amount - if expired then process the event. + */ +static void x25_timer(unsigned long param) +{ + struct sock *sk = (struct sock *)param; + + switch (sk->protinfo.x25->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 (sk->destroy || (sk->state == TCP_LISTEN && sk->dead)) { + del_timer(&sk->timer); + x25_destroy_socket(sk); + return; + } + break; + + case X25_STATE_3: + /* + * Check for the state of the receive buffer. + */ + if (atomic_read(&sk->rmem_alloc) < (sk->rcvbuf / 2) && + (sk->protinfo.x25->condition & X25_COND_OWN_RX_BUSY)) { + sk->protinfo.x25->condition &= ~X25_COND_OWN_RX_BUSY; + sk->protinfo.x25->condition &= ~X25_COND_ACK_PENDING; + sk->protinfo.x25->vl = sk->protinfo.x25->vr; + sk->protinfo.x25->timer = 0; + x25_write_internal(sk, X25_RR); + break; + } + /* + * Check for frames to transmit. + */ + x25_kick(sk); + break; + + default: + break; + } + + if (sk->protinfo.x25->timer == 0 || --sk->protinfo.x25->timer > 0) { + x25_set_timer(sk); + return; + } + + /* + * Timer has expired, it may have been T2, T21, T22, or T23. We can tell + * by the state machine state. + */ + switch (sk->protinfo.x25->state) { + case X25_STATE_3: /* T2 */ + if (sk->protinfo.x25->condition & X25_COND_ACK_PENDING) { + sk->protinfo.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); + sk->protinfo.x25->state = X25_STATE_2; + sk->protinfo.x25->timer = sk->protinfo.x25->t23; + break; + + case X25_STATE_2: /* T23 */ + x25_clear_queues(sk); + sk->protinfo.x25->state = X25_STATE_0; + sk->state = TCP_CLOSE; + sk->err = ETIMEDOUT; + sk->shutdown |= SEND_SHUTDOWN; + if (!sk->dead) + sk->state_change(sk); + sk->dead = 1; + break; + } + + x25_set_timer(sk); +} + +#endif |