[linux.git] / net / rose / rose_out.c

/*
 * This program 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.
 *
 * Copyright (C) Jonathan Naylor G4KLX ([email protected])
 */
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/gfp.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <net/rose.h>

/*
 *	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)
{
	struct rose_sock *rose = rose_sk(sk);

	if (skb == NULL)
		return;

	skb->data[2] |= (rose->vr << 5) & 0xE0;
	skb->data[2] |= (rose->vs << 1) & 0x0E;

	rose_start_idletimer(sk);

	rose_transmit_link(skb, rose->neighbour);
}

void rose_kick(struct sock *sk)
{
	struct rose_sock *rose = rose_sk(sk);
	struct sk_buff *skb, *skbn;
	unsigned short start, end;

	if (rose->state != ROSE_STATE_3)
		return;

	if (rose->condition & ROSE_COND_PEER_RX_BUSY)
		return;

	if (!skb_peek(&sk->sk_write_queue))
		return;

	start = (skb_peek(&rose->ack_queue) == NULL) ? rose->va : rose->vs;
	end   = (rose->va + sysctl_rose_window_size) % ROSE_MODULUS;

	if (start == end)
		return;

	rose->vs = start;

	/*
	 * Transmit data until either we're out of data to send or
	 * the window is full.
	 */

	skb  = skb_dequeue(&sk->sk_write_queue);

	do {
		if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
			skb_queue_head(&sk->sk_write_queue, skb);
			break;
		}

		skb_set_owner_w(skbn, sk);

		/*
		 * Transmit the frame copy.
		 */
		rose_send_iframe(sk, skbn);

		rose->vs = (rose->vs + 1) % ROSE_MODULUS;

		/*
		 * Requeue the original data frame.
		 */
		skb_queue_tail(&rose->ack_queue, skb);

	} while (rose->vs != end &&
		 (skb = skb_dequeue(&sk->sk_write_queue)) != NULL);

	rose->vl         = rose->vr;
	rose->condition &= ~ROSE_COND_ACK_PENDING;

	rose_stop_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)
{
	struct rose_sock *rose = rose_sk(sk);

	if (rose->condition & ROSE_COND_OWN_RX_BUSY)
		rose_write_internal(sk, ROSE_RNR);
	else
		rose_write_internal(sk, ROSE_RR);

	rose->vl         = rose->vr;
	rose->condition &= ~ROSE_COND_ACK_PENDING;

	rose_stop_timer(sk);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This program is free software; you can redistribute it and/or modify
	3	* it under the terms of the GNU General Public License as published by
	4	* the Free Software Foundation; either version 2 of the License, or
	5	* (at your option) any later version.
	6	*
	7	* Copyright (C) Jonathan Naylor G4KLX ([email protected])
	8	*/
	9	#include <linux/errno.h>
	10	#include <linux/types.h>
	11	#include <linux/socket.h>
	12	#include <linux/in.h>
	13	#include <linux/kernel.h>
1da177e4 LT	14	#include <linux/timer.h>
	15	#include <linux/string.h>
	16	#include <linux/sockios.h>
	17	#include <linux/net.h>
5a0e3ad6	18	#include <linux/gfp.h>
1da177e4 LT	19	#include <net/ax25.h>
	20	#include <linux/inet.h>
	21	#include <linux/netdevice.h>
	22	#include <linux/skbuff.h>
	23	#include <net/sock.h>
	24	#include <asm/system.h>
	25	#include <linux/fcntl.h>
	26	#include <linux/mm.h>
	27	#include <linux/interrupt.h>
	28	#include <net/rose.h>
	29
	30	/*
	31	* This procedure is passed a buffer descriptor for an iframe. It builds
	32	* the rest of the control part of the frame and then writes it out.
	33	*/
	34	static void rose_send_iframe(struct sock sk, struct sk_buff skb)
	35	{
	36	struct rose_sock *rose = rose_sk(sk);
	37
	38	if (skb == NULL)
	39	return;
	40
	41	skb->data[2] \|= (rose->vr << 5) & 0xE0;
	42	skb->data[2] \|= (rose->vs << 1) & 0x0E;
	43
	44	rose_start_idletimer(sk);
	45
	46	rose_transmit_link(skb, rose->neighbour);
	47	}
	48
	49	void rose_kick(struct sock *sk)
	50	{
	51	struct rose_sock *rose = rose_sk(sk);
	52	struct sk_buff skb, skbn;
	53	unsigned short start, end;
	54
	55	if (rose->state != ROSE_STATE_3)
	56	return;
	57
	58	if (rose->condition & ROSE_COND_PEER_RX_BUSY)
	59	return;
	60
	61	if (!skb_peek(&sk->sk_write_queue))
	62	return;
	63
	64	start = (skb_peek(&rose->ack_queue) == NULL) ? rose->va : rose->vs;
	65	end = (rose->va + sysctl_rose_window_size) % ROSE_MODULUS;
	66
	67	if (start == end)
	68	return;
	69
	70	rose->vs = start;
	71
	72	/*
	73	* Transmit data until either we're out of data to send or
	74	* the window is full.
	75	*/
	76
	77	skb = skb_dequeue(&sk->sk_write_queue);
	78
	79	do {
	80	if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
	81	skb_queue_head(&sk->sk_write_queue, skb);
	82	break;
83	}
84
85	skb_set_owner_w(skbn, sk);
86
87	/*
88	* Transmit the frame copy.
89	*/
90	rose_send_iframe(sk, skbn);
91
92	rose->vs = (rose->vs + 1) % ROSE_MODULUS;
93
94	/*
95	* Requeue the original data frame.
96	*/
97	skb_queue_tail(&rose->ack_queue, skb);
98
99	} while (rose->vs != end &&
100	(skb = skb_dequeue(&sk->sk_write_queue)) != NULL);
101
102	rose->vl = rose->vr;
103	rose->condition &= ~ROSE_COND_ACK_PENDING;
104
105	rose_stop_timer(sk);
106	}
107
108	/*
109	* The following routines are taken from page 170 of the 7th ARRL Computer
110	* Networking Conference paper, as is the whole state machine.
111	*/
112
113	void rose_enquiry_response(struct sock *sk)
114	{
115	struct rose_sock *rose = rose_sk(sk);
116
117	if (rose->condition & ROSE_COND_OWN_RX_BUSY)
118	rose_write_internal(sk, ROSE_RNR);
119	else
120	rose_write_internal(sk, ROSE_RR);
121
122	rose->vl = rose->vr;
123	rose->condition &= ~ROSE_COND_ACK_PENDING;
124
125	rose_stop_timer(sk);
126	}