xref: /openbmc/linux/arch/um/drivers/slip_kern.c (revision 22246614)
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 = dev->priv;
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);
95