1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
/*
* Linux ARCnet driver - "raw mode" packet encapsulation (no soft headers)
*
* Written 1994-1999 by Avery Pennarun.
* Derived from skeleton.c by Donald Becker.
*
* Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
* for sponsoring the further development of this driver.
*
* **********************
*
* 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
*
* **********************
*/
#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/init.h>
#include <linux/if_arp.h>
#include <net/arp.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include "arcdevice.h"
/* packet receiver */
static void rx(struct net_device *dev, int bufnum,
struct archdr *pkthdr, int length)
{
struct arcnet_local *lp = netdev_priv(dev);
struct sk_buff *skb;
struct archdr *pkt = pkthdr;
int ofs;
arc_printk(D_DURING, dev, "it's a raw packet (length=%d)\n", length);
if (length > MTU)
ofs = 512 - length;
else
ofs = 256 - length;
skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
if (!skb) {
dev->stats.rx_dropped++;
return;
}
skb_put(skb, length + ARC_HDR_SIZE);
skb->dev = dev;
pkt = (struct archdr *)skb->data;
skb_reset_mac_header(skb);
skb_pull(skb, ARC_HDR_SIZE);
/* up to sizeof(pkt->soft) has already been copied from the card */
memcpy(pkt, pkthdr, sizeof(struct archdr));
if (length > sizeof(pkt->soft))
lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
pkt->soft.raw + sizeof(pkt->soft),
length - sizeof(pkt->soft));
if (BUGLVL(D_SKB))
arcnet_dump_skb(dev, skb, "rx");
skb->protocol = cpu_to_be16(ETH_P_ARCNET);
netif_rx(skb);
}
/* Create the ARCnet hard/soft headers for raw mode.
* There aren't any soft headers in raw 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);
/* 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 = netdev_priv(dev);
struct arc_hardware *hard = &pkt->hard;
int ofs;
arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n",
lp->next_tx, lp->cur_tx, bufnum);
/* hard header is not included in packet length */
length -= ARC_HDR_SIZE;
if (length > XMTU) {
/* should never happen! other people already check for this. */
arc_printk(D_NORMAL, dev, "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;
}
arc_printk(D_DURING, dev, "prepare_tx: length=%d ofs=%d\n",
length, ofs);
lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft, length);
lp->lastload_dest = hard->dest;
return 1; /* done */
}
static struct ArcProto rawmode_proto = {
.suffix = 'r',
.mtu = XMTU,
.rx = rx,
.build_header = build_header,
.prepare_tx = prepare_tx,
.continue_tx = NULL,
.ack_tx = NULL
};
static int __init arcnet_raw_init(void)
{
int count;
pr_info("raw mode (`r') encapsulation support loaded\n");
for (count = 0; count < 256; count++)
if (arc_proto_map[count] == arc_proto_default)
arc_proto_map[count] = &rawmode_proto;
/* for raw mode, we only set the bcast proto if there's no better one */
if (arc_bcast_proto == arc_proto_default)
arc_bcast_proto = &rawmode_proto;
arc_proto_default = &rawmode_proto;
return 0;
}
static void __exit arcnet_raw_exit(void)
{
arcnet_unregister_proto(&rawmode_proto);
}
module_init(arcnet_raw_init);
module_exit(arcnet_raw_exit);
MODULE_LICENSE("GPL");
|
