diff options
Diffstat (limited to 'drivers/net/arcnet/arc-rawmode.c')
| -rw-r--r-- | drivers/net/arcnet/arc-rawmode.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/net/arcnet/arc-rawmode.c b/drivers/net/arcnet/arc-rawmode.c new file mode 100644 index 000000000..8c651fdee --- /dev/null +++ b/drivers/net/arcnet/arc-rawmode.c @@ -0,0 +1,189 @@ +/* + * 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 + * + * ********************** + */ + +#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt + +#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 "arcdevice.h" + +/* 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; + + arc_printk(D_DURING, dev, "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) { + 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)); + + if (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 = 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; + + arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n", + lp->next_tx, lp->cur_tx, bufnum); + + /* hard header is not included in packet length */ + length -= ARC_HDR_SIZE; + + if (length > XMTU) { + /* should never happen! other people already check for this. */ + arc_printk(D_NORMAL, dev, "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; + } + + arc_printk(D_DURING, dev, "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 */ +} + +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; + + pr_info("raw mode (`r') encapsulation support loaded\n"); + + 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"); |