xref: /openbmc/linux/net/802/fc.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
1 /*
2  * NET3:	Fibre Channel device handling subroutines
3  *
4  *		This program is free software; you can redistribute it and/or
5  *		modify it under the terms of the GNU General Public License
6  *		as published by the Free Software Foundation; either version
7  *		2 of the License, or (at your option) any later version.
8  *
9  *		Vineet Abraham <vma@iol.unh.edu>
10  *		v 1.0 03/22/99
11  */
12 
13 #include <linux/config.h>
14 #include <asm/uaccess.h>
15 #include <asm/system.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/string.h>
20 #include <linux/mm.h>
21 #include <linux/socket.h>
22 #include <linux/in.h>
23 #include <linux/inet.h>
24 #include <linux/netdevice.h>
25 #include <linux/fcdevice.h>
26 #include <linux/skbuff.h>
27 #include <linux/errno.h>
28 #include <linux/timer.h>
29 #include <linux/net.h>
30 #include <linux/proc_fs.h>
31 #include <linux/init.h>
32 #include <net/arp.h>
33 
34 /*
35  *	Put the headers on a Fibre Channel packet.
36  */
37 
38 static int fc_header(struct sk_buff *skb, struct net_device *dev,
39 		     unsigned short type,
40 		     void *daddr, void *saddr, unsigned len)
41 {
42 	struct fch_hdr *fch;
43 	int hdr_len;
44 
45 	/*
46 	 * Add the 802.2 SNAP header if IP as the IPv4 code calls
47 	 * dev->hard_header directly.
48 	 */
49 	if (type == ETH_P_IP || type == ETH_P_ARP)
50 	{
51 		struct fcllc *fcllc;
52 
53 		hdr_len = sizeof(struct fch_hdr) + sizeof(struct fcllc);
54 		fch = (struct fch_hdr *)skb_push(skb, hdr_len);
55 		fcllc = (struct fcllc *)(fch+1);
56 		fcllc->dsap = fcllc->ssap = EXTENDED_SAP;
57 		fcllc->llc = UI_CMD;
58 		fcllc->protid[0] = fcllc->protid[1] = fcllc->protid[2] = 0x00;
59 		fcllc->ethertype = htons(type);
60 	}
61 	else
62 	{
63 		hdr_len = sizeof(struct fch_hdr);
64 		fch = (struct fch_hdr *)skb_push(skb, hdr_len);
65 	}
66 
67 	if(saddr)
68 		memcpy(fch->saddr,saddr,dev->addr_len);
69 	else
70 		memcpy(fch->saddr,dev->dev_addr,dev->addr_len);
71 
72 	if(daddr)
73 	{
74 		memcpy(fch->daddr,daddr,dev->addr_len);
75 		return(hdr_len);
76 	}
77 	return -hdr_len;
78 }
79 
80 /*
81  *	A neighbour discovery of some species (eg arp) has completed. We
82  *	can now send the packet.
83  */
84 
85 static int fc_rebuild_header(struct sk_buff *skb)
86 {
87 	struct fch_hdr *fch=(struct fch_hdr *)skb->data;
88 	struct fcllc *fcllc=(struct fcllc *)(skb->data+sizeof(struct fch_hdr));
89 	if(fcllc->ethertype != htons(ETH_P_IP)) {
90 		printk("fc_rebuild_header: Don't know how to resolve type %04X addresses ?\n", ntohs(fcllc->ethertype));
91 		return 0;
92 	}
93 #ifdef CONFIG_INET
94 	return arp_find(fch->daddr, skb);
95 #else
96 	return 0;
97 #endif
98 }
99 
100 static void fc_setup(struct net_device *dev)
101 {
102 	dev->hard_header	= fc_header;
103 	dev->rebuild_header	= fc_rebuild_header;
104 
105 	dev->type		= ARPHRD_IEEE802;
106 	dev->hard_header_len	= FC_HLEN;
107 	dev->mtu		= 2024;
108 	dev->addr_len		= FC_ALEN;
109 	dev->tx_queue_len	= 100; /* Long queues on fc */
110 	dev->flags		= IFF_BROADCAST;
111 
112 	memset(dev->broadcast, 0xFF, FC_ALEN);
113 }
114 
115 /**
116  * alloc_fcdev - Register fibre channel device
117  * @sizeof_priv: Size of additional driver-private structure to be allocated
118  *	for this fibre channel device
119  *
120  * Fill in the fields of the device structure with fibre channel-generic values.
121  *
122  * Constructs a new net device, complete with a private data area of
123  * size @sizeof_priv.  A 32-byte (not bit) alignment is enforced for
124  * this private data area.
125  */
126 struct net_device *alloc_fcdev(int sizeof_priv)
127 {
128 	return alloc_netdev(sizeof_priv, "fc%d", fc_setup);
129 }
130 EXPORT_SYMBOL(alloc_fcdev);
131