blob: ba2f5e710af12cc7587f0503ea8dc177d2aba4ed [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Joe Perches22ded572013-10-28 12:53:21 -070037#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
38
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <linux/init.h>
41#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090042#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <linux/console.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/moduleparam.h>
Andy Shevchenko4cd57732013-06-04 19:46:26 +030045#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#include <linux/netpoll.h>
Satyam Sharma0bcc1812007-08-10 15:35:05 -070048#include <linux/inet.h>
49#include <linux/configfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
51MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
52MODULE_DESCRIPTION("Console driver for network interfaces");
53MODULE_LICENSE("GPL");
54
Satyam Sharmad39badf2007-08-10 15:27:24 -070055#define MAX_PARAM_LENGTH 256
56#define MAX_PRINT_CHUNK 1000
57
58static char config[MAX_PARAM_LENGTH];
59module_param_string(netconsole, config, MAX_PARAM_LENGTH, 0);
Niels de Vos61a2d072008-07-31 00:07:23 -070060MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]");
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Amerigo Wangc1a60852012-11-08 03:42:38 +000062static bool oops_only = false;
63module_param(oops_only, bool, 0600);
64MODULE_PARM_DESC(oops_only, "Only log oops messages");
65
Satyam Sharmad2b60882007-08-10 15:29:47 -070066#ifndef MODULE
67static int __init option_setup(char *opt)
68{
69 strlcpy(config, opt, MAX_PARAM_LENGTH);
70 return 1;
71}
72__setup("netconsole=", option_setup);
73#endif /* MODULE */
74
Satyam Sharmab5427c22007-08-10 15:33:40 -070075/* Linked list of all configured targets */
76static LIST_HEAD(target_list);
77
78/* This needs to be a spinlock because write_msg() cannot sleep */
79static DEFINE_SPINLOCK(target_list_lock);
80
Satyam Sharmadf180e32007-08-10 15:32:14 -070081/**
82 * struct netconsole_target - Represents a configured netconsole target.
Satyam Sharmab5427c22007-08-10 15:33:40 -070083 * @list: Links this target into the target_list.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070084 * @item: Links us into the configfs subsystem hierarchy.
85 * @enabled: On / off knob to enable / disable target.
86 * Visible from userspace (read-write).
87 * We maintain a strict 1:1 correspondence between this and
88 * whether the corresponding netpoll is active or inactive.
89 * Also, other parameters of a target may be modified at
90 * runtime only when it is disabled (enabled == 0).
Satyam Sharmadf180e32007-08-10 15:32:14 -070091 * @np: The netpoll structure for this target.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070092 * Contains the other userspace visible parameters:
93 * dev_name (read-write)
94 * local_port (read-write)
95 * remote_port (read-write)
96 * local_ip (read-write)
97 * remote_ip (read-write)
98 * local_mac (read-only)
99 * remote_mac (read-write)
Satyam Sharmadf180e32007-08-10 15:32:14 -0700100 */
101struct netconsole_target {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700102 struct list_head list;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700103#ifdef CONFIG_NETCONSOLE_DYNAMIC
104 struct config_item item;
105#endif
106 int enabled;
Dan Aloni7a163bf2013-08-30 13:59:46 +0300107 struct mutex mutex;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700108 struct netpoll np;
109};
110
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700111#ifdef CONFIG_NETCONSOLE_DYNAMIC
112
113static struct configfs_subsystem netconsole_subsys;
114
115static int __init dynamic_netconsole_init(void)
116{
117 config_group_init(&netconsole_subsys.su_group);
118 mutex_init(&netconsole_subsys.su_mutex);
119 return configfs_register_subsystem(&netconsole_subsys);
120}
121
122static void __exit dynamic_netconsole_exit(void)
123{
124 configfs_unregister_subsystem(&netconsole_subsys);
125}
126
127/*
128 * Targets that were created by parsing the boot/module option string
129 * do not exist in the configfs hierarchy (and have NULL names) and will
130 * never go away, so make these a no-op for them.
131 */
132static void netconsole_target_get(struct netconsole_target *nt)
133{
134 if (config_item_name(&nt->item))
135 config_item_get(&nt->item);
136}
137
138static void netconsole_target_put(struct netconsole_target *nt)
139{
140 if (config_item_name(&nt->item))
141 config_item_put(&nt->item);
142}
143
144#else /* !CONFIG_NETCONSOLE_DYNAMIC */
145
146static int __init dynamic_netconsole_init(void)
147{
148 return 0;
149}
150
151static void __exit dynamic_netconsole_exit(void)
152{
153}
154
155/*
156 * No danger of targets going away from under us when dynamic
157 * reconfigurability is off.
158 */
159static void netconsole_target_get(struct netconsole_target *nt)
160{
161}
162
163static void netconsole_target_put(struct netconsole_target *nt)
164{
165}
166
167#endif /* CONFIG_NETCONSOLE_DYNAMIC */
168
169/* Allocate new target (from boot/module param) and setup netpoll for it */
170static struct netconsole_target *alloc_param_target(char *target_config)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700171{
172 int err = -ENOMEM;
173 struct netconsole_target *nt;
174
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700175 /*
176 * Allocate and initialize with defaults.
177 * Note that these targets get their config_item fields zeroed-out.
178 */
Satyam Sharmab5427c22007-08-10 15:33:40 -0700179 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
Joe Perchese404dec2012-01-29 12:56:23 +0000180 if (!nt)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700181 goto fail;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700182
183 nt->np.name = "netconsole";
184 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
185 nt->np.local_port = 6665;
186 nt->np.remote_port = 6666;
Dan Aloni7a163bf2013-08-30 13:59:46 +0300187 mutex_init(&nt->mutex);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700188 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
189
190 /* Parse parameters and setup netpoll */
191 err = netpoll_parse_options(&nt->np, target_config);
192 if (err)
193 goto fail;
194
195 err = netpoll_setup(&nt->np);
196 if (err)
197 goto fail;
198
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700199 nt->enabled = 1;
200
Satyam Sharmab5427c22007-08-10 15:33:40 -0700201 return nt;
202
203fail:
204 kfree(nt);
205 return ERR_PTR(err);
206}
207
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700208/* Cleanup netpoll for given target (from boot/module param) and free it */
209static void free_param_target(struct netconsole_target *nt)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700210{
211 netpoll_cleanup(&nt->np);
212 kfree(nt);
213}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700215#ifdef CONFIG_NETCONSOLE_DYNAMIC
216
217/*
218 * Our subsystem hierarchy is:
219 *
220 * /sys/kernel/config/netconsole/
221 * |
222 * <target>/
223 * | enabled
224 * | dev_name
225 * | local_port
226 * | remote_port
227 * | local_ip
228 * | remote_ip
229 * | local_mac
230 * | remote_mac
231 * |
232 * <target>/...
233 */
234
235struct netconsole_target_attr {
236 struct configfs_attribute attr;
237 ssize_t (*show)(struct netconsole_target *nt,
238 char *buf);
239 ssize_t (*store)(struct netconsole_target *nt,
240 const char *buf,
241 size_t count);
242};
243
244static struct netconsole_target *to_target(struct config_item *item)
245{
246 return item ?
247 container_of(item, struct netconsole_target, item) :
248 NULL;
249}
250
251/*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700252 * Attribute operations for netconsole_target.
253 */
254
255static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
256{
257 return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
258}
259
260static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
261{
262 return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
263}
264
265static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
266{
267 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
268}
269
270static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
271{
272 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
273}
274
275static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
276{
Cong Wangb3d936f2013-01-07 20:52:41 +0000277 if (nt->np.ipv6)
278 return snprintf(buf, PAGE_SIZE, "%pI6c\n", &nt->np.local_ip.in6);
279 else
Cong Wangb7394d22013-01-07 20:52:39 +0000280 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700281}
282
283static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
284{
Cong Wangb3d936f2013-01-07 20:52:41 +0000285 if (nt->np.ipv6)
286 return snprintf(buf, PAGE_SIZE, "%pI6c\n", &nt->np.remote_ip.in6);
287 else
Cong Wangb7394d22013-01-07 20:52:39 +0000288 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700289}
290
291static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
292{
Stephen Hemminger09538642007-11-19 19:23:29 -0800293 struct net_device *dev = nt->np.dev;
Johannes Berge1749612008-10-27 15:59:26 -0700294 static const u8 bcast[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
Stephen Hemminger09538642007-11-19 19:23:29 -0800295
Johannes Berge1749612008-10-27 15:59:26 -0700296 return snprintf(buf, PAGE_SIZE, "%pM\n", dev ? dev->dev_addr : bcast);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700297}
298
299static ssize_t show_remote_mac(struct netconsole_target *nt, char *buf)
300{
Johannes Berge1749612008-10-27 15:59:26 -0700301 return snprintf(buf, PAGE_SIZE, "%pM\n", nt->np.remote_mac);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700302}
303
304/*
305 * This one is special -- targets created through the configfs interface
306 * are not enabled (and the corresponding netpoll activated) by default.
307 * The user is expected to set the desired parameters first (which
308 * would enable him to dynamically add new netpoll targets for new
309 * network interfaces as and when they come up).
310 */
311static ssize_t store_enabled(struct netconsole_target *nt,
312 const char *buf,
313 size_t count)
314{
Nikolay Aleksandrov45e526e2013-10-23 15:04:49 +0200315 unsigned long flags;
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000316 int enabled;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700317 int err;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700318
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000319 err = kstrtoint(buf, 10, &enabled);
320 if (err < 0)
321 return err;
322 if (enabled < 0 || enabled > 1)
323 return -EINVAL;
Gao fengd5123482011-10-11 16:08:11 +0000324 if (enabled == nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700325 pr_info("network logging has already %s\n",
326 nt->enabled ? "started" : "stopped");
Gao fengd5123482011-10-11 16:08:11 +0000327 return -EINVAL;
328 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700329
330 if (enabled) { /* 1 */
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700331 /*
332 * Skip netpoll_parse_options() -- all the attributes are
333 * already configured via configfs. Just print them out.
334 */
335 netpoll_print_options(&nt->np);
336
337 err = netpoll_setup(&nt->np);
Nikolay Aleksandrovc7c6eff2013-10-24 12:09:24 +0200338 if (err)
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700339 return err;
340
David S. Miller394efd12013-11-04 13:48:30 -0500341 pr_info("netconsole: network logging started\n");
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700342 } else { /* 0 */
Nikolay Aleksandrov45e526e2013-10-23 15:04:49 +0200343 /* We need to disable the netconsole before cleaning it up
344 * otherwise we might end up in write_msg() with
345 * nt->np.dev == NULL and nt->enabled == 1
346 */
347 spin_lock_irqsave(&target_list_lock, flags);
348 nt->enabled = 0;
349 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700350 netpoll_cleanup(&nt->np);
351 }
352
353 nt->enabled = enabled;
354
355 return strnlen(buf, count);
356}
357
358static ssize_t store_dev_name(struct netconsole_target *nt,
359 const char *buf,
360 size_t count)
361{
362 size_t len;
363
364 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700365 pr_err("target (%s) is enabled, disable to update parameters\n",
366 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700367 return -EINVAL;
368 }
369
370 strlcpy(nt->np.dev_name, buf, IFNAMSIZ);
371
372 /* Get rid of possible trailing newline from echo(1) */
373 len = strnlen(nt->np.dev_name, IFNAMSIZ);
374 if (nt->np.dev_name[len - 1] == '\n')
375 nt->np.dev_name[len - 1] = '\0';
376
377 return strnlen(buf, count);
378}
379
380static ssize_t store_local_port(struct netconsole_target *nt,
381 const char *buf,
382 size_t count)
383{
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000384 int rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700385
386 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700387 pr_err("target (%s) is enabled, disable to update parameters\n",
388 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700389 return -EINVAL;
390 }
391
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000392 rv = kstrtou16(buf, 10, &nt->np.local_port);
393 if (rv < 0)
394 return rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700395 return strnlen(buf, count);
396}
397
398static ssize_t store_remote_port(struct netconsole_target *nt,
399 const char *buf,
400 size_t count)
401{
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000402 int rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700403
404 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700405 pr_err("target (%s) is enabled, disable to update parameters\n",
406 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700407 return -EINVAL;
408 }
409
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000410 rv = kstrtou16(buf, 10, &nt->np.remote_port);
411 if (rv < 0)
412 return rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700413 return strnlen(buf, count);
414}
415
416static ssize_t store_local_ip(struct netconsole_target *nt,
417 const char *buf,
418 size_t count)
419{
420 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700421 pr_err("target (%s) is enabled, disable to update parameters\n",
422 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700423 return -EINVAL;
424 }
425
Cong Wangb3d936f2013-01-07 20:52:41 +0000426 if (strnchr(buf, count, ':')) {
427 const char *end;
428 if (in6_pton(buf, count, nt->np.local_ip.in6.s6_addr, -1, &end) > 0) {
429 if (*end && *end != '\n') {
Joe Perches22ded572013-10-28 12:53:21 -0700430 pr_err("invalid IPv6 address at: <%c>\n", *end);
Cong Wangb3d936f2013-01-07 20:52:41 +0000431 return -EINVAL;
432 }
433 nt->np.ipv6 = true;
434 } else
435 return -EINVAL;
436 } else {
437 if (!nt->np.ipv6) {
438 nt->np.local_ip.ip = in_aton(buf);
439 } else
440 return -EINVAL;
441 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700442
443 return strnlen(buf, count);
444}
445
446static ssize_t store_remote_ip(struct netconsole_target *nt,
447 const char *buf,
448 size_t count)
449{
450 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700451 pr_err("target (%s) is enabled, disable to update parameters\n",
452 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700453 return -EINVAL;
454 }
455
Cong Wangb3d936f2013-01-07 20:52:41 +0000456 if (strnchr(buf, count, ':')) {
457 const char *end;
458 if (in6_pton(buf, count, nt->np.remote_ip.in6.s6_addr, -1, &end) > 0) {
459 if (*end && *end != '\n') {
Joe Perches22ded572013-10-28 12:53:21 -0700460 pr_err("invalid IPv6 address at: <%c>\n", *end);
Cong Wangb3d936f2013-01-07 20:52:41 +0000461 return -EINVAL;
462 }
463 nt->np.ipv6 = true;
464 } else
465 return -EINVAL;
466 } else {
467 if (!nt->np.ipv6) {
468 nt->np.remote_ip.ip = in_aton(buf);
469 } else
470 return -EINVAL;
471 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700472
473 return strnlen(buf, count);
474}
475
476static ssize_t store_remote_mac(struct netconsole_target *nt,
477 const char *buf,
478 size_t count)
479{
480 u8 remote_mac[ETH_ALEN];
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700481
482 if (nt->enabled) {
Joe Perches22ded572013-10-28 12:53:21 -0700483 pr_err("target (%s) is enabled, disable to update parameters\n",
484 config_item_name(&nt->item));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700485 return -EINVAL;
486 }
487
Alexey Dobriyan4940fc82011-05-07 23:00:07 +0000488 if (!mac_pton(buf, remote_mac))
489 return -EINVAL;
490 if (buf[3 * ETH_ALEN - 1] && buf[3 * ETH_ALEN - 1] != '\n')
491 return -EINVAL;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700492 memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
493
494 return strnlen(buf, count);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700495}
496
497/*
498 * Attribute definitions for netconsole_target.
499 */
500
501#define NETCONSOLE_TARGET_ATTR_RO(_name) \
502static struct netconsole_target_attr netconsole_target_##_name = \
503 __CONFIGFS_ATTR(_name, S_IRUGO, show_##_name, NULL)
504
505#define NETCONSOLE_TARGET_ATTR_RW(_name) \
506static struct netconsole_target_attr netconsole_target_##_name = \
507 __CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)
508
509NETCONSOLE_TARGET_ATTR_RW(enabled);
510NETCONSOLE_TARGET_ATTR_RW(dev_name);
511NETCONSOLE_TARGET_ATTR_RW(local_port);
512NETCONSOLE_TARGET_ATTR_RW(remote_port);
513NETCONSOLE_TARGET_ATTR_RW(local_ip);
514NETCONSOLE_TARGET_ATTR_RW(remote_ip);
515NETCONSOLE_TARGET_ATTR_RO(local_mac);
516NETCONSOLE_TARGET_ATTR_RW(remote_mac);
517
518static struct configfs_attribute *netconsole_target_attrs[] = {
519 &netconsole_target_enabled.attr,
520 &netconsole_target_dev_name.attr,
521 &netconsole_target_local_port.attr,
522 &netconsole_target_remote_port.attr,
523 &netconsole_target_local_ip.attr,
524 &netconsole_target_remote_ip.attr,
525 &netconsole_target_local_mac.attr,
526 &netconsole_target_remote_mac.attr,
527 NULL,
528};
529
530/*
531 * Item operations and type for netconsole_target.
532 */
533
534static void netconsole_target_release(struct config_item *item)
535{
536 kfree(to_target(item));
537}
538
539static ssize_t netconsole_target_attr_show(struct config_item *item,
540 struct configfs_attribute *attr,
541 char *buf)
542{
543 ssize_t ret = -EINVAL;
544 struct netconsole_target *nt = to_target(item);
545 struct netconsole_target_attr *na =
546 container_of(attr, struct netconsole_target_attr, attr);
547
548 if (na->show)
549 ret = na->show(nt, buf);
550
551 return ret;
552}
553
554static ssize_t netconsole_target_attr_store(struct config_item *item,
555 struct configfs_attribute *attr,
556 const char *buf,
557 size_t count)
558{
559 ssize_t ret = -EINVAL;
560 struct netconsole_target *nt = to_target(item);
561 struct netconsole_target_attr *na =
562 container_of(attr, struct netconsole_target_attr, attr);
563
Nikolay Aleksandrovc7c6eff2013-10-24 12:09:24 +0200564 mutex_lock(&nt->mutex);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700565 if (na->store)
566 ret = na->store(nt, buf, count);
Nikolay Aleksandrovc7c6eff2013-10-24 12:09:24 +0200567 mutex_unlock(&nt->mutex);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700568
569 return ret;
570}
571
572static struct configfs_item_operations netconsole_target_item_ops = {
573 .release = netconsole_target_release,
574 .show_attribute = netconsole_target_attr_show,
575 .store_attribute = netconsole_target_attr_store,
576};
577
578static struct config_item_type netconsole_target_type = {
579 .ct_attrs = netconsole_target_attrs,
580 .ct_item_ops = &netconsole_target_item_ops,
581 .ct_owner = THIS_MODULE,
582};
583
584/*
585 * Group operations and type for netconsole_subsys.
586 */
587
Joel Beckerf89ab862008-07-17 14:53:48 -0700588static struct config_item *make_netconsole_target(struct config_group *group,
589 const char *name)
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700590{
591 unsigned long flags;
592 struct netconsole_target *nt;
593
594 /*
595 * Allocate and initialize with defaults.
596 * Target is disabled at creation (enabled == 0).
597 */
598 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
Joe Perchese404dec2012-01-29 12:56:23 +0000599 if (!nt)
Joel Beckera6795e92008-07-17 15:21:29 -0700600 return ERR_PTR(-ENOMEM);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700601
602 nt->np.name = "netconsole";
603 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
604 nt->np.local_port = 6665;
605 nt->np.remote_port = 6666;
Dan Aloni7a163bf2013-08-30 13:59:46 +0300606 mutex_init(&nt->mutex);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700607 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
608
609 /* Initialize the config_item member */
610 config_item_init_type_name(&nt->item, name, &netconsole_target_type);
611
612 /* Adding, but it is disabled */
613 spin_lock_irqsave(&target_list_lock, flags);
614 list_add(&nt->list, &target_list);
615 spin_unlock_irqrestore(&target_list_lock, flags);
616
Joel Beckerf89ab862008-07-17 14:53:48 -0700617 return &nt->item;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700618}
619
620static void drop_netconsole_target(struct config_group *group,
621 struct config_item *item)
622{
623 unsigned long flags;
624 struct netconsole_target *nt = to_target(item);
625
626 spin_lock_irqsave(&target_list_lock, flags);
627 list_del(&nt->list);
628 spin_unlock_irqrestore(&target_list_lock, flags);
629
630 /*
631 * The target may have never been enabled, or was manually disabled
632 * before being removed so netpoll may have already been cleaned up.
633 */
634 if (nt->enabled)
635 netpoll_cleanup(&nt->np);
636
637 config_item_put(&nt->item);
638}
639
640static struct configfs_group_operations netconsole_subsys_group_ops = {
641 .make_item = make_netconsole_target,
642 .drop_item = drop_netconsole_target,
643};
644
645static struct config_item_type netconsole_subsys_type = {
646 .ct_group_ops = &netconsole_subsys_group_ops,
647 .ct_owner = THIS_MODULE,
648};
649
650/* The netconsole configfs subsystem */
651static struct configfs_subsystem netconsole_subsys = {
652 .su_group = {
653 .cg_item = {
654 .ci_namebuf = "netconsole",
655 .ci_type = &netconsole_subsys_type,
656 },
657 },
658};
659
660#endif /* CONFIG_NETCONSOLE_DYNAMIC */
661
Satyam Sharma17951f32007-08-10 15:33:01 -0700662/* Handle network interface device notifications */
663static int netconsole_netdev_event(struct notifier_block *this,
Jiri Pirko351638e2013-05-28 01:30:21 +0000664 unsigned long event, void *ptr)
Satyam Sharma17951f32007-08-10 15:33:01 -0700665{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700666 unsigned long flags;
667 struct netconsole_target *nt;
Jiri Pirko351638e2013-05-28 01:30:21 +0000668 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
Ferenc Wagner141dfba2011-01-06 05:11:19 +0000669 bool stopped = false;
Satyam Sharma17951f32007-08-10 15:33:01 -0700670
WANG Cong0e34e932010-05-06 00:47:21 -0700671 if (!(event == NETDEV_CHANGENAME || event == NETDEV_UNREGISTER ||
Amerigo Wangdaf92092011-05-19 21:39:12 +0000672 event == NETDEV_RELEASE || event == NETDEV_JOIN))
Satyam Sharmab5427c22007-08-10 15:33:40 -0700673 goto done;
Satyam Sharma17951f32007-08-10 15:33:01 -0700674
Satyam Sharmab5427c22007-08-10 15:33:40 -0700675 spin_lock_irqsave(&target_list_lock, flags);
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000676restart:
Satyam Sharmab5427c22007-08-10 15:33:40 -0700677 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700678 netconsole_target_get(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700679 if (nt->np.dev == dev) {
680 switch (event) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700681 case NETDEV_CHANGENAME:
682 strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
683 break;
Amerigo Wangdaf92092011-05-19 21:39:12 +0000684 case NETDEV_RELEASE:
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000685 case NETDEV_JOIN:
Bruno Prémont2382b152009-04-29 20:45:17 +0000686 case NETDEV_UNREGISTER:
Nikolay Aleksandrovc71380f2013-09-19 15:02:36 +0200687 /* rtnl_lock already held
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000688 * we might sleep in __netpoll_cleanup()
Neil Horman3b410a32010-10-13 16:01:52 +0000689 */
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000690 spin_unlock_irqrestore(&target_list_lock, flags);
Dan Aloni7a163bf2013-08-30 13:59:46 +0300691
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000692 __netpoll_cleanup(&nt->np);
Dan Aloni7a163bf2013-08-30 13:59:46 +0300693
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000694 spin_lock_irqsave(&target_list_lock, flags);
695 dev_put(nt->np.dev);
696 nt->np.dev = NULL;
Bruno Prémont2382b152009-04-29 20:45:17 +0000697 nt->enabled = 0;
Ferenc Wagner141dfba2011-01-06 05:11:19 +0000698 stopped = true;
Veaceslav Falico3f315be2013-03-11 00:21:48 +0000699 netconsole_target_put(nt);
700 goto restart;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700701 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700702 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700703 netconsole_target_put(nt);
Satyam Sharma17951f32007-08-10 15:33:01 -0700704 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700705 spin_unlock_irqrestore(&target_list_lock, flags);
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000706 if (stopped) {
Joe Perches22ded572013-10-28 12:53:21 -0700707 const char *msg = "had an event";
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000708 switch (event) {
709 case NETDEV_UNREGISTER:
Joe Perches22ded572013-10-28 12:53:21 -0700710 msg = "unregistered";
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000711 break;
Amerigo Wangdaf92092011-05-19 21:39:12 +0000712 case NETDEV_RELEASE:
Joe Perches22ded572013-10-28 12:53:21 -0700713 msg = "released slaves";
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000714 break;
715 case NETDEV_JOIN:
Joe Perches22ded572013-10-28 12:53:21 -0700716 msg = "is joining a master device";
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000717 break;
718 }
Joe Perches22ded572013-10-28 12:53:21 -0700719 pr_info("network logging stopped on interface %s as it %s\n",
720 dev->name, msg);
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000721 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700722
Satyam Sharmab5427c22007-08-10 15:33:40 -0700723done:
Satyam Sharma17951f32007-08-10 15:33:01 -0700724 return NOTIFY_DONE;
725}
726
727static struct notifier_block netconsole_netdev_notifier = {
728 .notifier_call = netconsole_netdev_event,
729};
730
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731static void write_msg(struct console *con, const char *msg, unsigned int len)
732{
733 int frag, left;
734 unsigned long flags;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700735 struct netconsole_target *nt;
736 const char *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737
Amerigo Wangc1a60852012-11-08 03:42:38 +0000738 if (oops_only && !oops_in_progress)
739 return;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700740 /* Avoid taking lock and disabling interrupts unnecessarily */
741 if (list_empty(&target_list))
742 return;
743
744 spin_lock_irqsave(&target_list_lock, flags);
745 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700746 netconsole_target_get(nt);
747 if (nt->enabled && netif_running(nt->np.dev)) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700748 /*
749 * We nest this inside the for-each-target loop above
750 * so that we're able to get as much logging out to
751 * at least one target if we die inside here, instead
752 * of unnecessarily keeping all targets in lock-step.
753 */
754 tmp = msg;
755 for (left = len; left;) {
756 frag = min(left, MAX_PRINT_CHUNK);
757 netpoll_send_udp(&nt->np, tmp, frag);
758 tmp += frag;
759 left -= frag;
760 }
Satyam Sharma0cc120be2007-08-10 15:30:31 -0700761 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700762 netconsole_target_put(nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700764 spin_unlock_irqrestore(&target_list_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765}
766
767static struct console netconsole = {
Satyam Sharmad39badf2007-08-10 15:27:24 -0700768 .name = "netcon",
Michael Ellerman0517dee2008-04-15 00:49:04 -0700769 .flags = CON_ENABLED,
Satyam Sharmad39badf2007-08-10 15:27:24 -0700770 .write = write_msg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771};
772
Satyam Sharmad39badf2007-08-10 15:27:24 -0700773static int __init init_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774{
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700775 int err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700776 struct netconsole_target *nt, *tmp;
777 unsigned long flags;
778 char *target_config;
779 char *input = config;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700780
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700781 if (strnlen(input, MAX_PARAM_LENGTH)) {
782 while ((target_config = strsep(&input, ";"))) {
783 nt = alloc_param_target(target_config);
784 if (IS_ERR(nt)) {
785 err = PTR_ERR(nt);
786 goto fail;
787 }
Michael Ellerman0517dee2008-04-15 00:49:04 -0700788 /* Dump existing printks when we register */
789 netconsole.flags |= CON_PRINTBUFFER;
790
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700791 spin_lock_irqsave(&target_list_lock, flags);
792 list_add(&nt->list, &target_list);
793 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700794 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700795 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796
Satyam Sharma17951f32007-08-10 15:33:01 -0700797 err = register_netdevice_notifier(&netconsole_netdev_notifier);
798 if (err)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700799 goto fail;
Satyam Sharma17951f32007-08-10 15:33:01 -0700800
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700801 err = dynamic_netconsole_init();
802 if (err)
803 goto undonotifier;
804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 register_console(&netconsole);
Joe Perches22ded572013-10-28 12:53:21 -0700806 pr_info("network logging started\n");
Satyam Sharmad39badf2007-08-10 15:27:24 -0700807
Satyam Sharmad39badf2007-08-10 15:27:24 -0700808 return err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700809
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700810undonotifier:
811 unregister_netdevice_notifier(&netconsole_netdev_notifier);
812
Satyam Sharmab5427c22007-08-10 15:33:40 -0700813fail:
Joe Perches22ded572013-10-28 12:53:21 -0700814 pr_err("cleaning up\n");
Satyam Sharmab5427c22007-08-10 15:33:40 -0700815
816 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700817 * Remove all targets and destroy them (only targets created
818 * from the boot/module option exist here). Skipping the list
Satyam Sharmab5427c22007-08-10 15:33:40 -0700819 * lock is safe here, and netpoll_cleanup() will sleep.
820 */
821 list_for_each_entry_safe(nt, tmp, &target_list, list) {
822 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700823 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700824 }
825
826 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827}
828
Satyam Sharmad39badf2007-08-10 15:27:24 -0700829static void __exit cleanup_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700831 struct netconsole_target *nt, *tmp;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700832
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 unregister_console(&netconsole);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700834 dynamic_netconsole_exit();
Satyam Sharma17951f32007-08-10 15:33:01 -0700835 unregister_netdevice_notifier(&netconsole_netdev_notifier);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700836
837 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700838 * Targets created via configfs pin references on our module
839 * and would first be rmdir(2)'ed from userspace. We reach
840 * here only when they are already destroyed, and only those
841 * created from the boot/module option are left, so remove and
842 * destroy them. Skipping the list lock is safe here, and
843 * netpoll_cleanup() will sleep.
Satyam Sharmab5427c22007-08-10 15:33:40 -0700844 */
845 list_for_each_entry_safe(nt, tmp, &target_list, list) {
846 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700847 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700848 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849}
850
Lin Ming97c7de02011-09-20 15:45:07 -0400851/*
852 * Use late_initcall to ensure netconsole is
853 * initialized after network device driver if built-in.
854 *
855 * late_initcall() and module_init() are identical if built as module.
856 */
857late_initcall(init_netconsole);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858module_exit(cleanup_netconsole);