summaryrefslogtreecommitdiffstats
path: root/drivers/net/netconsole.c
blob: be15ca6205a85aae2164243f674bb5a7c27bd030 (plain)
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
/*
 *  linux/drivers/net/netconsole.c
 *
 *  Copyright (C) 2001  Ingo Molnar <mingo@redhat.com>
 *
 *  This file contains the implementation of an IRQ-safe, crash-safe
 *  kernel console implementation that outputs kernel messages to the
 *  network.
 *
 * Modification history:
 *
 * 2001-09-17    started by Ingo Molnar.
 * 2003-08-11    2.6 port by Matt Mackall
 *               simplified options
 *               generic card hooks
 *               works non-modular
 * 2003-09-07    rewritten with netpoll api
 */

/****************************************************************
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2, or (at your option)
 *      any later version.
 *
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *
 *      You should have received a copy of the GNU General Public License
 *      along with this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 ****************************************************************/

#include <linux/mm.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/console.h>
#include <linux/moduleparam.h>
#include <linux/string.h>
#include <linux/netpoll.h>

MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
MODULE_DESCRIPTION("Console driver for network interfaces");
MODULE_LICENSE("GPL");

#define MAX_PARAM_LENGTH	256
#define MAX_PRINT_CHUNK		1000

static char config[MAX_PARAM_LENGTH];
module_param_string(netconsole, config, MAX_PARAM_LENGTH, 0);
MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]\n");

#ifndef	MODULE
static int __init option_setup(char *opt)
{
	strlcpy(config, opt, MAX_PARAM_LENGTH);
	return 1;
}
__setup("netconsole=", option_setup);
#endif	/* MODULE */

/**
 * struct netconsole_target - Represents a configured netconsole target.
 * @np:		The netpoll structure for this target.
 */
struct netconsole_target {
	struct netpoll		np;
};

static struct netconsole_target default_target = {
	.np		= {
		.name		= "netconsole",
		.dev_name	= "eth0",
		.local_port	= 6665,
		.remote_port	= 6666,
		.remote_mac	= {0xff, 0xff, 0xff, 0xff, 0xff, 0xff},
	},
};

static void write_msg(struct console *con, const char *msg, unsigned int len)
{
	int frag, left;
	unsigned long flags;
	struct netconsole_target *nt = &default_target;

	if (netif_running(nt->np.dev)) {
		local_irq_save(flags);
		for (left = len; left;) {
			frag = min(left, MAX_PRINT_CHUNK);
			netpoll_send_udp(&nt->np, msg, frag);
			msg += frag;
			left -= frag;
		}
		local_irq_restore(flags);
	}
}

static struct console netconsole = {
	.name	= "netcon",
	.flags	= CON_ENABLED | CON_PRINTBUFFER,
	.write	= write_msg,
};

static int __init init_netconsole(void)
{
	int err = 0;
	struct netconsole_target *nt = &default_target;

	if (!strnlen(config, MAX_PARAM_LENGTH)) {
		printk(KERN_INFO "netconsole: not configured, aborting\n");
		goto out;
	}

	err = netpoll_parse_options(&nt->np, config);
	if (err)
		goto out;

	err = netpoll_setup(&nt->np);
	if (err)
		goto out;

	register_console(&netconsole);
	printk(KERN_INFO "netconsole: network logging started\n");

out:
	return err;
}

static void __exit cleanup_netconsole(void)
{
	struct netconsole_target *nt = &default_target;

	unregister_console(&netconsole);
	netpoll_cleanup(&nt->np);
}

module_init(init_netconsole);
module_exit(cleanup_netconsole);
OpenPOWER on IntegriCloud