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/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Pseudo-driver for the loopback interface.
*
* Version: @(#)loopback.c 1.0.4b 08/16/93
*
* Authors: Ross Biro, <bir7@leland.Stanford.Edu>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Donald Becker, <becker@cesdis.gsfc.nasa.gov>
*
* Alan Cox : Fixed oddments for NET3.014
*
* 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.
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/socket.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/in.h>
#include <linux/if_ether.h> /* For the statistics structure. */
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/io.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
static int
loopback_xmit(struct sk_buff *skb, struct device *dev)
{
struct enet_statistics *stats = (struct enet_statistics *)dev->priv;
int done;
if (skb == NULL || dev == NULL) return(0);
cli();
if (dev->tbusy != 0) {
sti();
stats->tx_errors++;
return(1);
}
dev->tbusy = 1;
sti();
/* FIXME: Optimise so buffers with skb->free=1 are not copied but
instead are lobbed from tx queue to rx queue */
done = dev_rint(skb->data, skb->len, 0, dev);
dev_kfree_skb(skb, FREE_WRITE);
while (done != 1) {
done = dev_rint(NULL, 0, 0, dev);
}
stats->tx_packets++;
dev->tbusy = 0;
#if 1
#if defined (__i386__)
__asm__("cmpl $0,_intr_count\n\t"
"jne 1f\n\t"
"movl _bh_active,%%eax\n\t"
"testl _bh_mask,%%eax\n\t"
"je 1f\n\t"
"incl _intr_count\n\t"
"call _do_bottom_half\n\t"
"decl _intr_count\n"
"1:"
:
:
: "ax", "dx", "cx");
#elif defined (__mips__)
if(intr_count == 0 && (bh_active & bh_mask) != 0) {
intr_count++;
do_bottom_half();
intr_count--;
}
#endif
#endif
return(0);
}
static struct enet_statistics *
get_stats(struct device *dev)
{
return (struct enet_statistics *)dev->priv;
}
static int loopback_open(struct device *dev)
{
dev->flags|=IFF_LOOPBACK;
return 0;
}
/* Initialize the rest of the LOOPBACK device. */
int
loopback_init(struct device *dev)
{
int i;
dev->mtu = 2000; /* MTU */
dev->tbusy = 0;
dev->hard_start_xmit = loopback_xmit;
dev->open = NULL;
#if 1
dev->hard_header = eth_header;
dev->hard_header_len = ETH_HLEN; /* 14 */
dev->addr_len = ETH_ALEN; /* 6 */
dev->type = ARPHRD_ETHER; /* 0x0001 */
dev->type_trans = eth_type_trans;
dev->rebuild_header = eth_rebuild_header;
dev->open = loopback_open;
#else
dev->hard_header_length = 0;
dev->addr_len = 0;
dev->type = 0; /* loopback_type (0) */
dev->hard_header = NULL;
dev->type_trans = NULL;
dev->rebuild_header = NULL;
#endif
/* New-style flags. */
dev->flags = IFF_LOOPBACK|IFF_BROADCAST;
dev->family = AF_INET;
#ifdef CONFIG_INET
dev->pa_addr = in_aton("127.0.0.1");
dev->pa_brdaddr = in_aton("127.255.255.255");
dev->pa_mask = in_aton("255.0.0.0");
dev->pa_alen = sizeof(unsigned long);
#endif
dev->priv = kmalloc(sizeof(struct enet_statistics), GFP_KERNEL);
memset(dev->priv, 0, sizeof(struct enet_statistics));
dev->get_stats = get_stats;
/* Fill in the generic fields of the device structure. */
for (i = 0; i < DEV_NUMBUFFS; i++)
skb_queue_head_init(&dev->buffs[i]);
return(0);
};
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