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/*
* Rose 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 2.1.0 or higher/ NET3.029
*
* 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
* Rose 001 Jonathan(G4KLX) Cloned from nr_out.c
*/
#include <linux/config.h>
#if defined(CONFIG_ROSE) || defined(CONFIG_ROSE_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 <net/ax25.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/rose.h>
/*
* This is where all Rose frames pass;
*/
void rose_output(struct sock *sk, struct sk_buff *skb)
{
struct sk_buff *skbn;
unsigned char header[ROSE_MIN_LEN];
int err, frontlen, len;
if (skb->len - ROSE_MIN_LEN > ROSE_PACLEN) {
/* Save a copy of the Header */
memcpy(header, skb->data, ROSE_MIN_LEN);
skb_pull(skb, ROSE_MIN_LEN);
frontlen = skb_headroom(skb);
while (skb->len > 0) {
if ((skbn = sock_alloc_send_skb(sk, frontlen + ROSE_PACLEN, 0, 0, &err)) == NULL)
return;
skbn->sk = sk;
skbn->free = 1;
skbn->arp = 1;
skb_reserve(skbn, frontlen);
len = (ROSE_PACLEN > skb->len) ? skb->len : ROSE_PACLEN;
/* Copy the user data */
memcpy(skb_put(skbn, len), skb->data, len);
skb_pull(skb, len);
/* Duplicate the Header */
skb_push(skbn, ROSE_MIN_LEN);
memcpy(skbn->data, header, ROSE_MIN_LEN);
if (skb->len > 0)
skbn->data[2] |= M_BIT;
skb_queue_tail(&sk->write_queue, skbn); /* Throw it on the queue */
}
skb->free = 1;
kfree_skb(skb, FREE_WRITE);
} else {
skb_queue_tail(&sk->write_queue, skb); /* Throw it on the queue */
}
if (sk->protinfo.rose->state == ROSE_STATE_3)
rose_kick(sk);
}
/*
* This procedure is passed a buffer descriptor for an iframe. It builds
* the rest of the control part of the frame and then writes it out.
*/
static void rose_send_iframe(struct sock *sk, struct sk_buff *skb)
{
if (skb == NULL)
return;
skb->data[2] |= (sk->protinfo.rose->vr << 5) & 0xE0;
skb->data[2] |= (sk->protinfo.rose->vs << 1) & 0x0E;
rose_transmit_link(skb, sk->protinfo.rose->neighbour);
}
void rose_kick(struct sock *sk)
{
struct sk_buff *skb, *skbn;
int last = 1;
unsigned short start, end, next;
del_timer(&sk->timer);
start = (skb_peek(&sk->protinfo.rose->ack_queue) == NULL) ? sk->protinfo.rose->va : sk->protinfo.rose->vs;
end = (sk->protinfo.rose->va + sk->window) % ROSE_MODULUS;
if (!(sk->protinfo.rose->condition & PEER_RX_BUSY_CONDITION) &&
start != end &&
skb_peek(&sk->write_queue) != NULL) {
sk->protinfo.rose->vs = start;
/*
* Transmit data until either we're out of data to send or
* the window is full.
*/
/*
* Dequeue the frame and copy it.
*/
skb = skb_dequeue(&sk->write_queue);
do {
if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
skb_queue_head(&sk->write_queue, skb);
break;
}
next = (sk->protinfo.rose->vs + 1) % ROSE_MODULUS;
last = (next == end);
/*
* Transmit the frame copy.
*/
rose_send_iframe(sk, skbn);
sk->protinfo.rose->vs = next;
/*
* Requeue the original data frame.
*/
skb_queue_tail(&sk->protinfo.rose->ack_queue, skb);
} while (!last && (skb = skb_dequeue(&sk->write_queue)) != NULL);
sk->protinfo.rose->vl = sk->protinfo.rose->vr;
}
rose_set_timer(sk);
}
/*
* The following routines are taken from page 170 of the 7th ARRL Computer
* Networking Conference paper, as is the whole state machine.
*/
void rose_enquiry_response(struct sock *sk)
{
if (sk->protinfo.rose->condition & OWN_RX_BUSY_CONDITION) {
rose_write_internal(sk, ROSE_RNR);
} else {
rose_write_internal(sk, ROSE_RR);
}
sk->protinfo.rose->vl = sk->protinfo.rose->vr;
}
void rose_check_iframes_acked(struct sock *sk, unsigned short nr)
{
if (sk->protinfo.rose->vs == nr) {
rose_frames_acked(sk, nr);
} else {
if (sk->protinfo.rose->va != nr) {
rose_frames_acked(sk, nr);
}
}
}
#endif
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