| /* |
| * 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 */ |
| } |