Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/net/netconsole.c | |
3 | * | |
4 | * Copyright (C) 2001 Ingo Molnar <mingo@redhat.com> | |
5 | * | |
6 | * This file contains the implementation of an IRQ-safe, crash-safe | |
7 | * kernel console implementation that outputs kernel messages to the | |
8 | * network. | |
9 | * | |
10 | * Modification history: | |
11 | * | |
12 | * 2001-09-17 started by Ingo Molnar. | |
13 | * 2003-08-11 2.6 port by Matt Mackall | |
14 | * simplified options | |
15 | * generic card hooks | |
16 | * works non-modular | |
17 | * 2003-09-07 rewritten with netpoll api | |
18 | */ | |
19 | ||
20 | /**************************************************************** | |
21 | * This program is free software; you can redistribute it and/or modify | |
22 | * it under the terms of the GNU General Public License as published by | |
23 | * the Free Software Foundation; either version 2, or (at your option) | |
24 | * any later version. | |
25 | * | |
26 | * This program is distributed in the hope that it will be useful, | |
27 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
28 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
29 | * GNU General Public License for more details. | |
30 | * | |
31 | * You should have received a copy of the GNU General Public License | |
32 | * along with this program; if not, write to the Free Software | |
33 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
34 | * | |
35 | ****************************************************************/ | |
36 | ||
37 | #include <linux/mm.h> | |
1da177e4 LT |
38 | #include <linux/init.h> |
39 | #include <linux/module.h> | |
40 | #include <linux/console.h> | |
1da177e4 LT |
41 | #include <linux/moduleparam.h> |
42 | #include <linux/string.h> | |
1da177e4 LT |
43 | #include <linux/netpoll.h> |
44 | ||
45 | MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>"); | |
46 | MODULE_DESCRIPTION("Console driver for network interfaces"); | |
47 | MODULE_LICENSE("GPL"); | |
48 | ||
d39badf0 SS |
49 | #define MAX_PARAM_LENGTH 256 |
50 | #define MAX_PRINT_CHUNK 1000 | |
51 | ||
52 | static char config[MAX_PARAM_LENGTH]; | |
53 | module_param_string(netconsole, config, MAX_PARAM_LENGTH, 0); | |
1da177e4 LT |
54 | MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]\n"); |
55 | ||
d2b60881 SS |
56 | #ifndef MODULE |
57 | static int __init option_setup(char *opt) | |
58 | { | |
59 | strlcpy(config, opt, MAX_PARAM_LENGTH); | |
60 | return 1; | |
61 | } | |
62 | __setup("netconsole=", option_setup); | |
63 | #endif /* MODULE */ | |
64 | ||
b5427c27 SS |
65 | /* Linked list of all configured targets */ |
66 | static LIST_HEAD(target_list); | |
67 | ||
68 | /* This needs to be a spinlock because write_msg() cannot sleep */ | |
69 | static DEFINE_SPINLOCK(target_list_lock); | |
70 | ||
df180e36 SS |
71 | /** |
72 | * struct netconsole_target - Represents a configured netconsole target. | |
b5427c27 | 73 | * @list: Links this target into the target_list. |
df180e36 SS |
74 | * @np: The netpoll structure for this target. |
75 | */ | |
76 | struct netconsole_target { | |
b5427c27 | 77 | struct list_head list; |
df180e36 SS |
78 | struct netpoll np; |
79 | }; | |
80 | ||
b5427c27 SS |
81 | /* Allocate new target and setup netpoll for it */ |
82 | static struct netconsole_target *alloc_target(char *target_config) | |
83 | { | |
84 | int err = -ENOMEM; | |
85 | struct netconsole_target *nt; | |
86 | ||
87 | /* Allocate and initialize with defaults */ | |
88 | nt = kzalloc(sizeof(*nt), GFP_KERNEL); | |
89 | if (!nt) { | |
90 | printk(KERN_ERR "netconsole: failed to allocate memory\n"); | |
91 | goto fail; | |
92 | } | |
93 | ||
94 | nt->np.name = "netconsole"; | |
95 | strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ); | |
96 | nt->np.local_port = 6665; | |
97 | nt->np.remote_port = 6666; | |
98 | memset(nt->np.remote_mac, 0xff, ETH_ALEN); | |
99 | ||
100 | /* Parse parameters and setup netpoll */ | |
101 | err = netpoll_parse_options(&nt->np, target_config); | |
102 | if (err) | |
103 | goto fail; | |
104 | ||
105 | err = netpoll_setup(&nt->np); | |
106 | if (err) | |
107 | goto fail; | |
108 | ||
109 | return nt; | |
110 | ||
111 | fail: | |
112 | kfree(nt); | |
113 | return ERR_PTR(err); | |
114 | } | |
115 | ||
116 | /* Cleanup netpoll for given target and free it */ | |
117 | static void free_target(struct netconsole_target *nt) | |
118 | { | |
119 | netpoll_cleanup(&nt->np); | |
120 | kfree(nt); | |
121 | } | |
1da177e4 | 122 | |
17951f34 SS |
123 | /* Handle network interface device notifications */ |
124 | static int netconsole_netdev_event(struct notifier_block *this, | |
125 | unsigned long event, | |
126 | void *ptr) | |
127 | { | |
b5427c27 SS |
128 | unsigned long flags; |
129 | struct netconsole_target *nt; | |
17951f34 | 130 | struct net_device *dev = ptr; |
17951f34 | 131 | |
b5427c27 SS |
132 | if (!(event == NETDEV_CHANGEADDR || event == NETDEV_CHANGENAME)) |
133 | goto done; | |
134 | ||
135 | spin_lock_irqsave(&target_list_lock, flags); | |
136 | list_for_each_entry(nt, &target_list, list) { | |
137 | if (nt->np.dev == dev) { | |
138 | switch (event) { | |
139 | case NETDEV_CHANGEADDR: | |
140 | memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN); | |
141 | break; | |
17951f34 | 142 | |
b5427c27 SS |
143 | case NETDEV_CHANGENAME: |
144 | strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ); | |
145 | break; | |
146 | } | |
17951f34 SS |
147 | } |
148 | } | |
b5427c27 | 149 | spin_unlock_irqrestore(&target_list_lock, flags); |
17951f34 | 150 | |
b5427c27 | 151 | done: |
17951f34 SS |
152 | return NOTIFY_DONE; |
153 | } | |
154 | ||
155 | static struct notifier_block netconsole_netdev_notifier = { | |
156 | .notifier_call = netconsole_netdev_event, | |
157 | }; | |
158 | ||
1da177e4 LT |
159 | static void write_msg(struct console *con, const char *msg, unsigned int len) |
160 | { | |
161 | int frag, left; | |
162 | unsigned long flags; | |
b5427c27 SS |
163 | struct netconsole_target *nt; |
164 | const char *tmp; | |
165 | ||
166 | /* Avoid taking lock and disabling interrupts unnecessarily */ | |
167 | if (list_empty(&target_list)) | |
168 | return; | |
169 | ||
170 | spin_lock_irqsave(&target_list_lock, flags); | |
171 | list_for_each_entry(nt, &target_list, list) { | |
172 | if (netif_running(nt->np.dev)) { | |
173 | /* | |
174 | * We nest this inside the for-each-target loop above | |
175 | * so that we're able to get as much logging out to | |
176 | * at least one target if we die inside here, instead | |
177 | * of unnecessarily keeping all targets in lock-step. | |
178 | */ | |
179 | tmp = msg; | |
180 | for (left = len; left;) { | |
181 | frag = min(left, MAX_PRINT_CHUNK); | |
182 | netpoll_send_udp(&nt->np, tmp, frag); | |
183 | tmp += frag; | |
184 | left -= frag; | |
185 | } | |
0cc120be | 186 | } |
1da177e4 | 187 | } |
b5427c27 | 188 | spin_unlock_irqrestore(&target_list_lock, flags); |
1da177e4 LT |
189 | } |
190 | ||
191 | static struct console netconsole = { | |
d39badf0 SS |
192 | .name = "netcon", |
193 | .flags = CON_ENABLED | CON_PRINTBUFFER, | |
194 | .write = write_msg, | |
1da177e4 LT |
195 | }; |
196 | ||
d39badf0 | 197 | static int __init init_netconsole(void) |
1da177e4 | 198 | { |
d39badf0 | 199 | int err = 0; |
b5427c27 SS |
200 | struct netconsole_target *nt, *tmp; |
201 | unsigned long flags; | |
202 | char *target_config; | |
203 | char *input = config; | |
b41848b6 | 204 | |
b5427c27 | 205 | if (!strnlen(input, MAX_PARAM_LENGTH)) { |
d39badf0 SS |
206 | printk(KERN_INFO "netconsole: not configured, aborting\n"); |
207 | goto out; | |
1da177e4 LT |
208 | } |
209 | ||
b5427c27 SS |
210 | while ((target_config = strsep(&input, ";"))) { |
211 | nt = alloc_target(target_config); | |
212 | if (IS_ERR(nt)) { | |
213 | err = PTR_ERR(nt); | |
214 | goto fail; | |
215 | } | |
216 | spin_lock_irqsave(&target_list_lock, flags); | |
217 | list_add(&nt->list, &target_list); | |
218 | spin_unlock_irqrestore(&target_list_lock, flags); | |
219 | } | |
1da177e4 | 220 | |
17951f34 SS |
221 | err = register_netdevice_notifier(&netconsole_netdev_notifier); |
222 | if (err) | |
b5427c27 | 223 | goto fail; |
17951f34 | 224 | |
1da177e4 LT |
225 | register_console(&netconsole); |
226 | printk(KERN_INFO "netconsole: network logging started\n"); | |
d39badf0 SS |
227 | |
228 | out: | |
229 | return err; | |
b5427c27 SS |
230 | |
231 | fail: | |
232 | printk(KERN_ERR "netconsole: cleaning up\n"); | |
233 | ||
234 | /* | |
235 | * Remove all targets and destroy them. Skipping the list | |
236 | * lock is safe here, and netpoll_cleanup() will sleep. | |
237 | */ | |
238 | list_for_each_entry_safe(nt, tmp, &target_list, list) { | |
239 | list_del(&nt->list); | |
240 | free_target(nt); | |
241 | } | |
242 | ||
243 | return err; | |
1da177e4 LT |
244 | } |
245 | ||
d39badf0 | 246 | static void __exit cleanup_netconsole(void) |
1da177e4 | 247 | { |
b5427c27 | 248 | struct netconsole_target *nt, *tmp; |
df180e36 | 249 | |
1da177e4 | 250 | unregister_console(&netconsole); |
17951f34 | 251 | unregister_netdevice_notifier(&netconsole_netdev_notifier); |
b5427c27 SS |
252 | |
253 | /* | |
254 | * Remove all targets and destroy them. Skipping the list | |
255 | * lock is safe here, and netpoll_cleanup() will sleep. | |
256 | */ | |
257 | list_for_each_entry_safe(nt, tmp, &target_list, list) { | |
258 | list_del(&nt->list); | |
259 | free_target(nt); | |
260 | } | |
1da177e4 LT |
261 | } |
262 | ||
263 | module_init(init_netconsole); | |
264 | module_exit(cleanup_netconsole); |