xref: /openbmc/linux/net/802/fc.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * NET3:	Fibre Channel device handling subroutines
4  *
5  *		Vineet Abraham <vma@iol.unh.edu>
6  *		v 1.0 03/22/99
7  */
8 
9 #include <linux/uaccess.h>
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/mm.h>
14 #include <linux/socket.h>
15 #include <linux/in.h>
16 #include <linux/inet.h>
17 #include <linux/netdevice.h>
18 #include <linux/fcdevice.h>
19 #include <linux/skbuff.h>
20 #include <linux/errno.h>
21 #include <linux/timer.h>
22 #include <linux/net.h>
23 #include <linux/proc_fs.h>
24 #include <linux/init.h>
25 #include <linux/export.h>
26 #include <net/arp.h>
27 
28 /*
29  *	Put the headers on a Fibre Channel packet.
30  */
31 
32 static int fc_header(struct sk_buff *skb, struct net_device *dev,
33 		     unsigned short type,
34 		     const void *daddr, const void *saddr, unsigned int len)
35 {
36 	struct fch_hdr *fch;
37 	int hdr_len;
38 
39 	/*
40 	 * Add the 802.2 SNAP header if IP as the IPv4 code calls
41 	 * dev->hard_header directly.
42 	 */
43 	if (type == ETH_P_IP || type == ETH_P_ARP)
44 	{
45 		struct fcllc *fcllc;
46 
47 		hdr_len = sizeof(struct fch_hdr) + sizeof(struct fcllc);
48 		fch = skb_push(skb, hdr_len);
49 		fcllc = (struct fcllc *)(fch+1);
50 		fcllc->dsap = fcllc->ssap = EXTENDED_SAP;
51 		fcllc->llc = UI_CMD;
52 		fcllc->protid[0] = fcllc->protid[1] = fcllc->protid[2] = 0x00;
53 		fcllc->ethertype = htons(type);
54 	}
55 	else
56 	{
57 		hdr_len = sizeof(struct fch_hdr);
58 		fch = skb_push(skb, hdr_len);
59 	}
60 
61 	if(saddr)
62 		memcpy(fch->saddr,saddr,dev->addr_len);
63 	else
64 		memcpy(fch->saddr,dev->dev_addr,dev->addr_len);
65 
66 	if(daddr)
67 	{
68 		memcpy(fch->daddr,daddr,dev->addr_len);
69 		return hdr_len;
70 	}
71 	return -hdr_len;
72 }
73 
74 static const struct header_ops fc_header_ops = {
75 	.create	 = fc_header,
76 };
77 
78 static void fc_setup(struct net_device *dev)
79 {
80 	dev->header_ops		= &fc_header_ops;
81 	dev->type		= ARPHRD_IEEE802;
82 	dev->hard_header_len	= FC_HLEN;
83 	dev->mtu		= 2024;
84 	dev->addr_len		= FC_ALEN;
85 	dev->tx_queue_len	= 100; /* Long queues on fc */
86 	dev->flags		= IFF_BROADCAST;
87 
88 	memset(dev->broadcast, 0xFF, FC_ALEN);
89 }
90 
91 /**
92  * alloc_fcdev - Register fibre channel device
93  * @sizeof_priv: Size of additional driver-private structure to be allocated
94  *	for this fibre channel device
95  *
96  * Fill in the fields of the device structure with fibre channel-generic values.
97  *
98  * Constructs a new net device, complete with a private data area of
99  * size @sizeof_priv.  A 32-byte (not bit) alignment is enforced for
100  * this private data area.
101  */
102 struct net_device *alloc_fcdev(int sizeof_priv)
103 {
104 	return alloc_netdev(sizeof_priv, "fc%d", NET_NAME_UNKNOWN, fc_setup);
105 }
106 EXPORT_SYMBOL(alloc_fcdev);
107