1 files changed, 296 insertions, 0 deletions

diff --git a/drivers/net/arcnet/capmode.c b/drivers/net/arcnet/capmode.c
new file mode 100644
index 000000000000..16e155b04129
--- /dev/null
+++ b/drivers/net/arcnet/capmode.c
@@ -0,0 +1,296 @@
+/*
+ * Linux ARCnet driver - "cap mode" packet encapsulation.
+ * It adds sequence numbers to packets for communicating between a user space
+ * application and the driver. After a transmit it sends a packet with protocol
+ * byte 0 back up to the userspace containing the sequence number of the packet
+ * plus the transmit-status on the ArcNet.
+ *
+ * Written 2002-4 by Esben Nielsen, Vestas Wind Systems A/S
+ * Derived from arc-rawmode.c by Avery Pennarun.
+ * arc-rawmode was in turned based on skeleton.c, see below.
+ *
+ * **********************
+ *
+ * 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: cap mode (`c') 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 int ack_tx(struct net_device *dev, int acked);
+
+
+struct ArcProto capmode_proto =
+{
+        'r',
+        XMTU,
+        0,
+        rx,
+        build_header,
+        prepare_tx,
+        NULL,
+        ack_tx
+};
+
+
+void arcnet_cap_init(void)
+{
+        int count;
+
+        for (count = 1; count <= 8; count++)
+                if (arc_proto_map[count] == arc_proto_default)
+                        arc_proto_map[count] = &capmode_proto;
+
+        /* for cap mode, we only set the bcast proto if there's no better one */
+        if (arc_bcast_proto == arc_proto_default)
+                arc_bcast_proto = &capmode_proto;
+
+        arc_proto_default = &capmode_proto;
+        arc_raw_proto = &capmode_proto;
+}
+
+
+#ifdef MODULE
+
+int __init init_module(void)
+{
+        printk(VERSION);
+        arcnet_cap_init();
+        return 0;
+}
+
+void cleanup_module(void)
+{
+        arcnet_unregister_proto(&capmode_proto);
+}
+
+MODULE_LICENSE("GPL");
+#endif                          /* MODULE */
+
+
+
+/* packet receiver */
+static void rx(struct net_device *dev, int bufnum,
+               struct archdr *pkthdr, int length)
+{
+        struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+        struct sk_buff *skb;
+        struct archdr *pkt = pkthdr;
+        char *pktbuf, *pkthdrbuf;
+        int ofs;
+
+        BUGMSG(D_DURING, "it's a raw(cap) packet (length=%d)\n", length);
+
+        if (length >= MinTU)
+                ofs = 512 - length;
+        else
+                ofs = 256 - length;
+
+        skb = alloc_skb(length + ARC_HDR_SIZE + sizeof(int), 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 + sizeof(int));
+        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 */
+        /* squeeze in an int for the cap encapsulation */
+
+        /* use these variables to be sure we count in bytes, not in
+           sizeof(struct archdr) */
+        pktbuf=(char*)pkt;
+        pkthdrbuf=(char*)pkthdr;
+        memcpy(pktbuf, pkthdrbuf, ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto));
+        memcpy(pktbuf+ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto)+sizeof(int),
+               pkthdrbuf+ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto),
+               sizeof(struct archdr)-ARC_HDR_SIZE-sizeof(pkt->soft.cap.proto));
+
+        if (length > sizeof(pkt->soft))
+                lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
+                                      pkt->soft.raw + sizeof(pkt->soft)
+                                      + sizeof(int),
+                                      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 cap mode.
+ * There aren't any soft headers in cap 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);
+
+        BUGMSG(D_PROTO, "Preparing header for cap packet %x.\n",
+               *((int*)&pkt->soft.cap.cookie[0]));
+        /*
+         * 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 = (struct arcnet_local *) dev->priv;
+        struct arc_hardware *hard = &pkt->hard;
+        int ofs;
+
+
+        /* hard header is not included in packet length */
+        length -= ARC_HDR_SIZE;
+        /* And neither is the cookie field */
+        length -= sizeof(int);
+
+        BUGMSG(D_DURING, "prepare_tx: txbufs=%d/%d/%d\n",
+               lp->next_tx, lp->cur_tx, bufnum);
+
+        BUGMSG(D_PROTO, "Sending for cap packet %x.\n",
+               *((int*)&pkt->soft.cap.cookie[0]));
+
+        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);
+
+        // Copy the arcnet-header + the protocol byte down:
+        lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
+        lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft.cap.proto,
+                            sizeof(pkt->soft.cap.proto));
+
+        // Skip the extra integer we have written into it as a cookie
+        // but write the rest of the message:
+        lp->hw.copy_to_card(dev, bufnum, ofs+1,
+                            ((unsigned char*)&pkt->soft.cap.mes),length-1);
+
+        lp->lastload_dest = hard->dest;
+
+        return 1;               /* done */
+}
+
+
+static int ack_tx(struct net_device *dev, int acked)
+{
+  struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+  struct sk_buff *ackskb;
+  struct archdr *ackpkt;
+  int length=sizeof(struct arc_cap);
+
+  BUGMSG(D_DURING, "capmode: ack_tx: protocol: %x: result: %d\n",
+         lp->outgoing.skb->protocol, acked);
+
+  BUGLVL(D_SKB) arcnet_dump_skb(dev, lp->outgoing.skb, "ack_tx");
+
+  /* Now alloc a skb to send back up through the layers: */
+  ackskb = alloc_skb(length + ARC_HDR_SIZE , GFP_ATOMIC);
+  if (ackskb == NULL) {
+          BUGMSG(D_NORMAL, "Memory squeeze, can't acknowledge.\n");
+          goto free_outskb;
+  }
+
+  skb_put(ackskb, length + ARC_HDR_SIZE );
+  ackskb->dev = dev;
+
+  ackpkt = (struct archdr *) ackskb->data;
+
+  ackskb->mac.raw = ackskb->data;
+  /* skb_pull(ackskb, ARC_HDR_SIZE); */
+
+
+  memcpy(ackpkt, lp->outgoing.skb->data, ARC_HDR_SIZE+sizeof(struct arc_cap));
+  ackpkt->soft.cap.proto=0; /* using protocol 0 for acknowledge */
+  ackpkt->soft.cap.mes.ack=acked;
+
+  BUGMSG(D_PROTO, "Ackknowledge for cap packet %x.\n",
+         *((int*)&ackpkt->soft.cap.cookie[0]));
+
+  ackskb->protocol = __constant_htons(ETH_P_ARCNET);
+
+  BUGLVL(D_SKB) arcnet_dump_skb(dev, ackskb, "ack_tx_recv");
+  netif_rx(ackskb);
+
+ free_outskb:
+  dev_kfree_skb_irq(lp->outgoing.skb);
+  lp->outgoing.proto = NULL; /* We are always finished when in this protocol */
+
+  return 0;
+}