204 lines
5.2 KiB
C
Executable File
204 lines
5.2 KiB
C
Executable File
/*
|
|
* Linux ARCnet driver - "raw mode" packet encapsulation (no soft headers)
|
|
*
|
|
* Written 1994-1999 by Avery Pennarun.
|
|
* Derived from skeleton.c by Donald Becker.
|
|
*
|
|
* Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
|
|
* for sponsoring the further development of this driver.
|
|
*
|
|
* **********************
|
|
*
|
|
* The original copyright of skeleton.c was as follows:
|
|
*
|
|
* skeleton.c Written 1993 by Donald Becker.
|
|
* Copyright 1993 United States Government as represented by the
|
|
* Director, National Security Agency. This software may only be used
|
|
* and distributed according to the terms of the GNU General Public License as
|
|
* modified by SRC, incorporated herein by reference.
|
|
*
|
|
* **********************
|
|
*
|
|
* For more details, see drivers/net/arcnet.c
|
|
*
|
|
* **********************
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/init.h>
|
|
#include <linux/if_arp.h>
|
|
#include <net/arp.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/arcdevice.h>
|
|
|
|
#define VERSION "arcnet: raw mode (`r') encapsulation support loaded.\n"
|
|
|
|
|
|
static void rx(struct net_device *dev, int bufnum,
|
|
struct archdr *pkthdr, int length);
|
|
static int build_header(struct sk_buff *skb, struct net_device *dev,
|
|
unsigned short type, uint8_t daddr);
|
|
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
|
|
int bufnum);
|
|
|
|
static struct ArcProto rawmode_proto =
|
|
{
|
|
.suffix = 'r',
|
|
.mtu = XMTU,
|
|
.rx = rx,
|
|
.build_header = build_header,
|
|
.prepare_tx = prepare_tx,
|
|
.continue_tx = NULL,
|
|
.ack_tx = NULL
|
|
};
|
|
|
|
|
|
static int __init arcnet_raw_init(void)
|
|
{
|
|
int count;
|
|
|
|
printk(VERSION);
|
|
|
|
for (count = 0; count < 256; count++)
|
|
if (arc_proto_map[count] == arc_proto_default)
|
|
arc_proto_map[count] = &rawmode_proto;
|
|
|
|
/* for raw mode, we only set the bcast proto if there's no better one */
|
|
if (arc_bcast_proto == arc_proto_default)
|
|
arc_bcast_proto = &rawmode_proto;
|
|
|
|
arc_proto_default = &rawmode_proto;
|
|
return 0;
|
|
}
|
|
|
|
static void __exit arcnet_raw_exit(void)
|
|
{
|
|
arcnet_unregister_proto(&rawmode_proto);
|
|
}
|
|
|
|
module_init(arcnet_raw_init);
|
|
module_exit(arcnet_raw_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
|
|
/* packet receiver */
|
|
static void rx(struct net_device *dev, int bufnum,
|
|
struct archdr *pkthdr, int length)
|
|
{
|
|
struct arcnet_local *lp = netdev_priv(dev);
|
|
struct sk_buff *skb;
|
|
struct archdr *pkt = pkthdr;
|
|
int ofs;
|
|
|
|
BUGMSG(D_DURING, "it's a raw packet (length=%d)\n", length);
|
|
|
|
if (length > MTU)
|
|
ofs = 512 - length;
|
|
else
|
|
ofs = 256 - length;
|
|
|
|
skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
|
|
if (skb == NULL) {
|
|
BUGMSG(D_NORMAL, "Memory squeeze, dropping packet.\n");
|
|
dev->stats.rx_dropped++;
|
|
return;
|
|
}
|
|
skb_put(skb, length + ARC_HDR_SIZE);
|
|
skb->dev = dev;
|
|
|
|
pkt = (struct archdr *) skb->data;
|
|
|
|
skb_reset_mac_header(skb);
|
|
skb_pull(skb, ARC_HDR_SIZE);
|
|
|
|
/* up to sizeof(pkt->soft) has already been copied from the card */
|
|
memcpy(pkt, pkthdr, sizeof(struct archdr));
|
|
if (length > sizeof(pkt->soft))
|
|
lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
|
|
pkt->soft.raw + sizeof(pkt->soft),
|
|
length - sizeof(pkt->soft));
|
|
|
|
BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "rx");
|
|
|
|
skb->protocol = cpu_to_be16(ETH_P_ARCNET);
|
|
netif_rx(skb);
|
|
}
|
|
|
|
|
|
/*
|
|
* Create the ARCnet hard/soft headers for raw mode.
|
|
* There aren't any soft headers in raw mode - not even the protocol id.
|
|
*/
|
|
static int build_header(struct sk_buff *skb, struct net_device *dev,
|
|
unsigned short type, uint8_t daddr)
|
|
{
|
|
int hdr_size = ARC_HDR_SIZE;
|
|
struct archdr *pkt = (struct archdr *) skb_push(skb, hdr_size);
|
|
|
|
/*
|
|
* Set the source hardware address.
|
|
*
|
|
* This is pretty pointless for most purposes, but it can help in
|
|
* debugging. ARCnet does not allow us to change the source address in
|
|
* the actual packet sent)
|
|
*/
|
|
pkt->hard.source = *dev->dev_addr;
|
|
|
|
/* see linux/net/ethernet/eth.c to see where I got the following */
|
|
|
|
if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
|
|
/*
|
|
* FIXME: fill in the last byte of the dest ipaddr here to better
|
|
* comply with RFC1051 in "noarp" mode.
|
|
*/
|
|
pkt->hard.dest = 0;
|
|
return hdr_size;
|
|
}
|
|
/* otherwise, just fill it in and go! */
|
|
pkt->hard.dest = daddr;
|
|
|
|
return hdr_size; /* success */
|
|
}
|
|
|
|
|
|
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
|
|
int bufnum)
|
|
{
|
|
struct arcnet_local *lp = netdev_priv(dev);
|
|
struct arc_hardware *hard = &pkt->hard;
|
|
int ofs;
|
|
|
|
BUGMSG(D_DURING, "prepare_tx: txbufs=%d/%d/%d\n",
|
|
lp->next_tx, lp->cur_tx, bufnum);
|
|
|
|
length -= ARC_HDR_SIZE; /* hard header is not included in packet length */
|
|
|
|
if (length > XMTU) {
|
|
/* should never happen! other people already check for this. */
|
|
BUGMSG(D_NORMAL, "Bug! prepare_tx with size %d (> %d)\n",
|
|
length, XMTU);
|
|
length = XMTU;
|
|
}
|
|
if (length >= MinTU) {
|
|
hard->offset[0] = 0;
|
|
hard->offset[1] = ofs = 512 - length;
|
|
} else if (length > MTU) {
|
|
hard->offset[0] = 0;
|
|
hard->offset[1] = ofs = 512 - length - 3;
|
|
} else
|
|
hard->offset[0] = ofs = 256 - length;
|
|
|
|
BUGMSG(D_DURING, "prepare_tx: length=%d ofs=%d\n",
|
|
length,ofs);
|
|
|
|
lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
|
|
lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft, length);
|
|
|
|
lp->lastload_dest = hard->dest;
|
|
|
|
return 1; /* done */
|
|
}
|