arch/um/drivers/slip_kern.c

   1 /*
   2  * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   3  * Licensed under the GPL.
   4  */
   5
   6 #include <linux/if_arp.h>
   7 #include <linux/init.h>
   8 #include <linux/netdevice.h>
   9 #include "net_kern.h"
  10 #include "slip.h"
  11
  12 struct slip_init {
  13         char *gate_addr;
  14 };
  15
  16 static void slip_init(struct net_device *dev, void *data)
  17 {
  18         struct uml_net_private *private;
  19         struct slip_data *spri;
  20         struct slip_init *init = data;
  21
  22         private = netdev_priv(dev);
  23         spri = (struct slip_data *) private->user;
  24
  25         memset(spri->name, 0, sizeof(spri->name));
  26         spri->addr = NULL;
  27         spri->gate_addr = init->gate_addr;
  28         spri->slave = -1;
  29         spri->dev = dev;
  30
  31         slip_proto_init(&spri->slip);
  32
  33         dev->init = NULL;
  34         dev->hard_header_len = 0;
  35         dev->header_ops = NULL;
  36         dev->addr_len = 0;
  37         dev->type = ARPHRD_SLIP;
  38         dev->tx_queue_len = 256;
  39         dev->flags = IFF_NOARP;
  40         printk("SLIP backend - SLIP IP = %s\n", spri->gate_addr);
  41 }
  42
  43 static unsigned short slip_protocol(struct sk_buff *skbuff)
  44 {
  45         return htons(ETH_P_IP);
  46 }
  47
  48 static int slip_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
  49 {
  50         return slip_user_read(fd, skb_mac_header(skb), skb->dev->mtu,
  51                               (struct slip_data *) &lp->user);
  52 }
  53
  54 static int slip_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
  55 {
  56         return slip_user_write(fd, skb->data, skb->len,
  57                                (struct slip_data *) &lp->user);
  58 }
  59
  60 static const struct net_kern_info slip_kern_info = {
  61         .init                   = slip_init,
  62         .protocol               = slip_protocol,
  63         .read                   = slip_read,
  64         .write                  = slip_write,
  65 };
  66
  67 static int slip_setup(char *str, char **mac_out, void *data)
  68 {
  69         struct slip_init *init = data;
  70
  71         *init = ((struct slip_init) { .gate_addr = NULL });
  72
  73         if (str[0] != '\0')
  74                 init->gate_addr = str;
  75         return 1;
  76 }
  77
  78 static struct transport slip_transport = {
  79         .list           = LIST_HEAD_INIT(slip_transport.list),
  80         .name           = "slip",
  81         .setup          = slip_setup,
  82         .user           = &slip_user_info,
  83         .kern           = &slip_kern_info,
  84         .private_size   = sizeof(struct slip_data),
  85         .setup_size     = sizeof(struct slip_init),
  86 };
  87
  88 static int register_slip(void)
  89 {
  90         register_transport(&slip_transport);
  91         return 0;
  92 }
  93
  94 late_initcall(register_slip);