/* * 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/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); 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 = dev->priv; struct sk_buff *skb; struct archdr *pkt = pkthdr; int ofs; BUGMSG(D_DURING, "it's a raw packet (length=%d)\n", length); if (length >= MinTU) 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"); lp->stats.rx_dropped++; return; } skb_put(skb, length + ARC_HDR_SIZE); skb->dev = dev; pkt = (struct archdr *) skb->data; skb->mac.raw = skb->data; 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 = __constant_htons(ETH_P_ARCNET); ; netif_rx(skb); dev->last_rx = jiffies; } /* * 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 = dev->priv; 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 */ }