blob: dfc82720065ac0d68bb657dbf19150ff7dd4c89e [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
37#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include <linux/init.h>
39#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include <linux/console.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/moduleparam.h>
43#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#include <linux/netpoll.h>
Satyam Sharma0bcc1812007-08-10 15:35:05 -070045#include <linux/inet.h>
46#include <linux/configfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
49MODULE_DESCRIPTION("Console driver for network interfaces");
50MODULE_LICENSE("GPL");
51
Satyam Sharmad39badf2007-08-10 15:27:24 -070052#define MAX_PARAM_LENGTH 256
53#define MAX_PRINT_CHUNK 1000
54
55static char config[MAX_PARAM_LENGTH];
56module_param_string(netconsole, config, MAX_PARAM_LENGTH, 0);
Niels de Vos61a2d072008-07-31 00:07:23 -070057MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]");
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Satyam Sharmad2b60882007-08-10 15:29:47 -070059#ifndef MODULE
60static int __init option_setup(char *opt)
61{
62 strlcpy(config, opt, MAX_PARAM_LENGTH);
63 return 1;
64}
65__setup("netconsole=", option_setup);
66#endif /* MODULE */
67
Satyam Sharmab5427c22007-08-10 15:33:40 -070068/* Linked list of all configured targets */
69static LIST_HEAD(target_list);
70
71/* This needs to be a spinlock because write_msg() cannot sleep */
72static DEFINE_SPINLOCK(target_list_lock);
73
Satyam Sharmadf180e32007-08-10 15:32:14 -070074/**
75 * struct netconsole_target - Represents a configured netconsole target.
Satyam Sharmab5427c22007-08-10 15:33:40 -070076 * @list: Links this target into the target_list.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070077 * @item: Links us into the configfs subsystem hierarchy.
78 * @enabled: On / off knob to enable / disable target.
79 * Visible from userspace (read-write).
80 * We maintain a strict 1:1 correspondence between this and
81 * whether the corresponding netpoll is active or inactive.
82 * Also, other parameters of a target may be modified at
83 * runtime only when it is disabled (enabled == 0).
Satyam Sharmadf180e32007-08-10 15:32:14 -070084 * @np: The netpoll structure for this target.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070085 * Contains the other userspace visible parameters:
86 * dev_name (read-write)
87 * local_port (read-write)
88 * remote_port (read-write)
89 * local_ip (read-write)
90 * remote_ip (read-write)
91 * local_mac (read-only)
92 * remote_mac (read-write)
Satyam Sharmadf180e32007-08-10 15:32:14 -070093 */
94struct netconsole_target {
Satyam Sharmab5427c22007-08-10 15:33:40 -070095 struct list_head list;
Satyam Sharma0bcc1812007-08-10 15:35:05 -070096#ifdef CONFIG_NETCONSOLE_DYNAMIC
97 struct config_item item;
98#endif
99 int enabled;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700100 struct netpoll np;
101};
102
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700103#ifdef CONFIG_NETCONSOLE_DYNAMIC
104
105static struct configfs_subsystem netconsole_subsys;
106
107static int __init dynamic_netconsole_init(void)
108{
109 config_group_init(&netconsole_subsys.su_group);
110 mutex_init(&netconsole_subsys.su_mutex);
111 return configfs_register_subsystem(&netconsole_subsys);
112}
113
114static void __exit dynamic_netconsole_exit(void)
115{
116 configfs_unregister_subsystem(&netconsole_subsys);
117}
118
119/*
120 * Targets that were created by parsing the boot/module option string
121 * do not exist in the configfs hierarchy (and have NULL names) and will
122 * never go away, so make these a no-op for them.
123 */
124static void netconsole_target_get(struct netconsole_target *nt)
125{
126 if (config_item_name(&nt->item))
127 config_item_get(&nt->item);
128}
129
130static void netconsole_target_put(struct netconsole_target *nt)
131{
132 if (config_item_name(&nt->item))
133 config_item_put(&nt->item);
134}
135
136#else /* !CONFIG_NETCONSOLE_DYNAMIC */
137
138static int __init dynamic_netconsole_init(void)
139{
140 return 0;
141}
142
143static void __exit dynamic_netconsole_exit(void)
144{
145}
146
147/*
148 * No danger of targets going away from under us when dynamic
149 * reconfigurability is off.
150 */
151static void netconsole_target_get(struct netconsole_target *nt)
152{
153}
154
155static void netconsole_target_put(struct netconsole_target *nt)
156{
157}
158
159#endif /* CONFIG_NETCONSOLE_DYNAMIC */
160
161/* Allocate new target (from boot/module param) and setup netpoll for it */
162static struct netconsole_target *alloc_param_target(char *target_config)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700163{
164 int err = -ENOMEM;
165 struct netconsole_target *nt;
166
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700167 /*
168 * Allocate and initialize with defaults.
169 * Note that these targets get their config_item fields zeroed-out.
170 */
Satyam Sharmab5427c22007-08-10 15:33:40 -0700171 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
172 if (!nt) {
173 printk(KERN_ERR "netconsole: failed to allocate memory\n");
174 goto fail;
175 }
176
177 nt->np.name = "netconsole";
178 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
179 nt->np.local_port = 6665;
180 nt->np.remote_port = 6666;
181 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
182
183 /* Parse parameters and setup netpoll */
184 err = netpoll_parse_options(&nt->np, target_config);
185 if (err)
186 goto fail;
187
188 err = netpoll_setup(&nt->np);
189 if (err)
190 goto fail;
191
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700192 nt->enabled = 1;
193
Satyam Sharmab5427c22007-08-10 15:33:40 -0700194 return nt;
195
196fail:
197 kfree(nt);
198 return ERR_PTR(err);
199}
200
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700201/* Cleanup netpoll for given target (from boot/module param) and free it */
202static void free_param_target(struct netconsole_target *nt)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700203{
204 netpoll_cleanup(&nt->np);
205 kfree(nt);
206}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700208#ifdef CONFIG_NETCONSOLE_DYNAMIC
209
210/*
211 * Our subsystem hierarchy is:
212 *
213 * /sys/kernel/config/netconsole/
214 * |
215 * <target>/
216 * | enabled
217 * | dev_name
218 * | local_port
219 * | remote_port
220 * | local_ip
221 * | remote_ip
222 * | local_mac
223 * | remote_mac
224 * |
225 * <target>/...
226 */
227
228struct netconsole_target_attr {
229 struct configfs_attribute attr;
230 ssize_t (*show)(struct netconsole_target *nt,
231 char *buf);
232 ssize_t (*store)(struct netconsole_target *nt,
233 const char *buf,
234 size_t count);
235};
236
237static struct netconsole_target *to_target(struct config_item *item)
238{
239 return item ?
240 container_of(item, struct netconsole_target, item) :
241 NULL;
242}
243
244/*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700245 * Attribute operations for netconsole_target.
246 */
247
248static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
249{
250 return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
251}
252
253static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
254{
255 return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
256}
257
258static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
259{
260 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
261}
262
263static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
264{
265 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
266}
267
268static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
269{
Harvey Harrisone7557af2009-03-28 15:38:31 +0000270 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700271}
272
273static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
274{
Harvey Harrisone7557af2009-03-28 15:38:31 +0000275 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700276}
277
278static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
279{
Stephen Hemminger09538642007-11-19 19:23:29 -0800280 struct net_device *dev = nt->np.dev;
Johannes Berge1749612008-10-27 15:59:26 -0700281 static const u8 bcast[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
Stephen Hemminger09538642007-11-19 19:23:29 -0800282
Johannes Berge1749612008-10-27 15:59:26 -0700283 return snprintf(buf, PAGE_SIZE, "%pM\n", dev ? dev->dev_addr : bcast);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700284}
285
286static ssize_t show_remote_mac(struct netconsole_target *nt, char *buf)
287{
Johannes Berge1749612008-10-27 15:59:26 -0700288 return snprintf(buf, PAGE_SIZE, "%pM\n", nt->np.remote_mac);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700289}
290
291/*
292 * This one is special -- targets created through the configfs interface
293 * are not enabled (and the corresponding netpoll activated) by default.
294 * The user is expected to set the desired parameters first (which
295 * would enable him to dynamically add new netpoll targets for new
296 * network interfaces as and when they come up).
297 */
298static ssize_t store_enabled(struct netconsole_target *nt,
299 const char *buf,
300 size_t count)
301{
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000302 int enabled;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700303 int err;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700304
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000305 err = kstrtoint(buf, 10, &enabled);
306 if (err < 0)
307 return err;
308 if (enabled < 0 || enabled > 1)
309 return -EINVAL;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700310
311 if (enabled) { /* 1 */
312
313 /*
314 * Skip netpoll_parse_options() -- all the attributes are
315 * already configured via configfs. Just print them out.
316 */
317 netpoll_print_options(&nt->np);
318
319 err = netpoll_setup(&nt->np);
320 if (err)
321 return err;
322
323 printk(KERN_INFO "netconsole: network logging started\n");
324
325 } else { /* 0 */
326 netpoll_cleanup(&nt->np);
327 }
328
329 nt->enabled = enabled;
330
331 return strnlen(buf, count);
332}
333
334static ssize_t store_dev_name(struct netconsole_target *nt,
335 const char *buf,
336 size_t count)
337{
338 size_t len;
339
340 if (nt->enabled) {
341 printk(KERN_ERR "netconsole: target (%s) is enabled, "
342 "disable to update parameters\n",
343 config_item_name(&nt->item));
344 return -EINVAL;
345 }
346
347 strlcpy(nt->np.dev_name, buf, IFNAMSIZ);
348
349 /* Get rid of possible trailing newline from echo(1) */
350 len = strnlen(nt->np.dev_name, IFNAMSIZ);
351 if (nt->np.dev_name[len - 1] == '\n')
352 nt->np.dev_name[len - 1] = '\0';
353
354 return strnlen(buf, count);
355}
356
357static ssize_t store_local_port(struct netconsole_target *nt,
358 const char *buf,
359 size_t count)
360{
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000361 int rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700362
363 if (nt->enabled) {
364 printk(KERN_ERR "netconsole: target (%s) is enabled, "
365 "disable to update parameters\n",
366 config_item_name(&nt->item));
367 return -EINVAL;
368 }
369
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000370 rv = kstrtou16(buf, 10, &nt->np.local_port);
371 if (rv < 0)
372 return rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700373 return strnlen(buf, count);
374}
375
376static ssize_t store_remote_port(struct netconsole_target *nt,
377 const char *buf,
378 size_t count)
379{
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000380 int rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700381
382 if (nt->enabled) {
383 printk(KERN_ERR "netconsole: target (%s) is enabled, "
384 "disable to update parameters\n",
385 config_item_name(&nt->item));
386 return -EINVAL;
387 }
388
Alexey Dobriyan99f823f2011-05-07 20:33:13 +0000389 rv = kstrtou16(buf, 10, &nt->np.remote_port);
390 if (rv < 0)
391 return rv;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700392 return strnlen(buf, count);
393}
394
395static ssize_t store_local_ip(struct netconsole_target *nt,
396 const char *buf,
397 size_t count)
398{
399 if (nt->enabled) {
400 printk(KERN_ERR "netconsole: target (%s) is enabled, "
401 "disable to update parameters\n",
402 config_item_name(&nt->item));
403 return -EINVAL;
404 }
405
Harvey Harrisone7557af2009-03-28 15:38:31 +0000406 nt->np.local_ip = in_aton(buf);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700407
408 return strnlen(buf, count);
409}
410
411static ssize_t store_remote_ip(struct netconsole_target *nt,
412 const char *buf,
413 size_t count)
414{
415 if (nt->enabled) {
416 printk(KERN_ERR "netconsole: target (%s) is enabled, "
417 "disable to update parameters\n",
418 config_item_name(&nt->item));
419 return -EINVAL;
420 }
421
Harvey Harrisone7557af2009-03-28 15:38:31 +0000422 nt->np.remote_ip = in_aton(buf);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700423
424 return strnlen(buf, count);
425}
426
427static ssize_t store_remote_mac(struct netconsole_target *nt,
428 const char *buf,
429 size_t count)
430{
431 u8 remote_mac[ETH_ALEN];
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700432
433 if (nt->enabled) {
434 printk(KERN_ERR "netconsole: target (%s) is enabled, "
435 "disable to update parameters\n",
436 config_item_name(&nt->item));
437 return -EINVAL;
438 }
439
Alexey Dobriyan4940fc82011-05-07 23:00:07 +0000440 if (!mac_pton(buf, remote_mac))
441 return -EINVAL;
442 if (buf[3 * ETH_ALEN - 1] && buf[3 * ETH_ALEN - 1] != '\n')
443 return -EINVAL;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700444 memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
445
446 return strnlen(buf, count);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700447}
448
449/*
450 * Attribute definitions for netconsole_target.
451 */
452
453#define NETCONSOLE_TARGET_ATTR_RO(_name) \
454static struct netconsole_target_attr netconsole_target_##_name = \
455 __CONFIGFS_ATTR(_name, S_IRUGO, show_##_name, NULL)
456
457#define NETCONSOLE_TARGET_ATTR_RW(_name) \
458static struct netconsole_target_attr netconsole_target_##_name = \
459 __CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)
460
461NETCONSOLE_TARGET_ATTR_RW(enabled);
462NETCONSOLE_TARGET_ATTR_RW(dev_name);
463NETCONSOLE_TARGET_ATTR_RW(local_port);
464NETCONSOLE_TARGET_ATTR_RW(remote_port);
465NETCONSOLE_TARGET_ATTR_RW(local_ip);
466NETCONSOLE_TARGET_ATTR_RW(remote_ip);
467NETCONSOLE_TARGET_ATTR_RO(local_mac);
468NETCONSOLE_TARGET_ATTR_RW(remote_mac);
469
470static struct configfs_attribute *netconsole_target_attrs[] = {
471 &netconsole_target_enabled.attr,
472 &netconsole_target_dev_name.attr,
473 &netconsole_target_local_port.attr,
474 &netconsole_target_remote_port.attr,
475 &netconsole_target_local_ip.attr,
476 &netconsole_target_remote_ip.attr,
477 &netconsole_target_local_mac.attr,
478 &netconsole_target_remote_mac.attr,
479 NULL,
480};
481
482/*
483 * Item operations and type for netconsole_target.
484 */
485
486static void netconsole_target_release(struct config_item *item)
487{
488 kfree(to_target(item));
489}
490
491static ssize_t netconsole_target_attr_show(struct config_item *item,
492 struct configfs_attribute *attr,
493 char *buf)
494{
495 ssize_t ret = -EINVAL;
496 struct netconsole_target *nt = to_target(item);
497 struct netconsole_target_attr *na =
498 container_of(attr, struct netconsole_target_attr, attr);
499
500 if (na->show)
501 ret = na->show(nt, buf);
502
503 return ret;
504}
505
506static ssize_t netconsole_target_attr_store(struct config_item *item,
507 struct configfs_attribute *attr,
508 const char *buf,
509 size_t count)
510{
511 ssize_t ret = -EINVAL;
512 struct netconsole_target *nt = to_target(item);
513 struct netconsole_target_attr *na =
514 container_of(attr, struct netconsole_target_attr, attr);
515
516 if (na->store)
517 ret = na->store(nt, buf, count);
518
519 return ret;
520}
521
522static struct configfs_item_operations netconsole_target_item_ops = {
523 .release = netconsole_target_release,
524 .show_attribute = netconsole_target_attr_show,
525 .store_attribute = netconsole_target_attr_store,
526};
527
528static struct config_item_type netconsole_target_type = {
529 .ct_attrs = netconsole_target_attrs,
530 .ct_item_ops = &netconsole_target_item_ops,
531 .ct_owner = THIS_MODULE,
532};
533
534/*
535 * Group operations and type for netconsole_subsys.
536 */
537
Joel Beckerf89ab862008-07-17 14:53:48 -0700538static struct config_item *make_netconsole_target(struct config_group *group,
539 const char *name)
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700540{
541 unsigned long flags;
542 struct netconsole_target *nt;
543
544 /*
545 * Allocate and initialize with defaults.
546 * Target is disabled at creation (enabled == 0).
547 */
548 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
549 if (!nt) {
550 printk(KERN_ERR "netconsole: failed to allocate memory\n");
Joel Beckera6795e92008-07-17 15:21:29 -0700551 return ERR_PTR(-ENOMEM);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700552 }
553
554 nt->np.name = "netconsole";
555 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
556 nt->np.local_port = 6665;
557 nt->np.remote_port = 6666;
558 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
559
560 /* Initialize the config_item member */
561 config_item_init_type_name(&nt->item, name, &netconsole_target_type);
562
563 /* Adding, but it is disabled */
564 spin_lock_irqsave(&target_list_lock, flags);
565 list_add(&nt->list, &target_list);
566 spin_unlock_irqrestore(&target_list_lock, flags);
567
Joel Beckerf89ab862008-07-17 14:53:48 -0700568 return &nt->item;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700569}
570
571static void drop_netconsole_target(struct config_group *group,
572 struct config_item *item)
573{
574 unsigned long flags;
575 struct netconsole_target *nt = to_target(item);
576
577 spin_lock_irqsave(&target_list_lock, flags);
578 list_del(&nt->list);
579 spin_unlock_irqrestore(&target_list_lock, flags);
580
581 /*
582 * The target may have never been enabled, or was manually disabled
583 * before being removed so netpoll may have already been cleaned up.
584 */
585 if (nt->enabled)
586 netpoll_cleanup(&nt->np);
587
588 config_item_put(&nt->item);
589}
590
591static struct configfs_group_operations netconsole_subsys_group_ops = {
592 .make_item = make_netconsole_target,
593 .drop_item = drop_netconsole_target,
594};
595
596static struct config_item_type netconsole_subsys_type = {
597 .ct_group_ops = &netconsole_subsys_group_ops,
598 .ct_owner = THIS_MODULE,
599};
600
601/* The netconsole configfs subsystem */
602static struct configfs_subsystem netconsole_subsys = {
603 .su_group = {
604 .cg_item = {
605 .ci_namebuf = "netconsole",
606 .ci_type = &netconsole_subsys_type,
607 },
608 },
609};
610
611#endif /* CONFIG_NETCONSOLE_DYNAMIC */
612
Satyam Sharma17951f32007-08-10 15:33:01 -0700613/* Handle network interface device notifications */
614static int netconsole_netdev_event(struct notifier_block *this,
615 unsigned long event,
616 void *ptr)
617{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700618 unsigned long flags;
619 struct netconsole_target *nt;
Satyam Sharma17951f32007-08-10 15:33:01 -0700620 struct net_device *dev = ptr;
Ferenc Wagner141dfba2011-01-06 05:11:19 +0000621 bool stopped = false;
Satyam Sharma17951f32007-08-10 15:33:01 -0700622
WANG Cong0e34e932010-05-06 00:47:21 -0700623 if (!(event == NETDEV_CHANGENAME || event == NETDEV_UNREGISTER ||
Amerigo Wangdaf92092011-05-19 21:39:12 +0000624 event == NETDEV_RELEASE || event == NETDEV_JOIN))
Satyam Sharmab5427c22007-08-10 15:33:40 -0700625 goto done;
Satyam Sharma17951f32007-08-10 15:33:01 -0700626
Satyam Sharmab5427c22007-08-10 15:33:40 -0700627 spin_lock_irqsave(&target_list_lock, flags);
628 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700629 netconsole_target_get(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700630 if (nt->np.dev == dev) {
631 switch (event) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700632 case NETDEV_CHANGENAME:
633 strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
634 break;
Amerigo Wangdaf92092011-05-19 21:39:12 +0000635 case NETDEV_RELEASE:
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000636 case NETDEV_JOIN:
Bruno Prémont2382b152009-04-29 20:45:17 +0000637 case NETDEV_UNREGISTER:
Neil Horman3b410a32010-10-13 16:01:52 +0000638 /*
639 * rtnl_lock already held
640 */
641 if (nt->np.dev) {
Neil Horman13f172f2011-04-22 08:10:59 +0000642 spin_unlock_irqrestore(
643 &target_list_lock,
644 flags);
Neil Horman3b410a32010-10-13 16:01:52 +0000645 __netpoll_cleanup(&nt->np);
Neil Horman13f172f2011-04-22 08:10:59 +0000646 spin_lock_irqsave(&target_list_lock,
647 flags);
Neil Horman3b410a32010-10-13 16:01:52 +0000648 dev_put(nt->np.dev);
649 nt->np.dev = NULL;
Neil Horman13f172f2011-04-22 08:10:59 +0000650 netconsole_target_put(nt);
Neil Horman3b410a32010-10-13 16:01:52 +0000651 }
Bruno Prémont2382b152009-04-29 20:45:17 +0000652 nt->enabled = 0;
Ferenc Wagner141dfba2011-01-06 05:11:19 +0000653 stopped = true;
Bruno Prémont2382b152009-04-29 20:45:17 +0000654 break;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700655 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700656 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700657 netconsole_target_put(nt);
Satyam Sharma17951f32007-08-10 15:33:01 -0700658 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700659 spin_unlock_irqrestore(&target_list_lock, flags);
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000660 if (stopped) {
Ferenc Wagner38cfb902011-01-06 05:11:20 +0000661 printk(KERN_INFO "netconsole: network logging stopped on "
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000662 "interface %s as it ", dev->name);
663 switch (event) {
664 case NETDEV_UNREGISTER:
665 printk(KERN_CONT "unregistered\n");
666 break;
Amerigo Wangdaf92092011-05-19 21:39:12 +0000667 case NETDEV_RELEASE:
Amerigo Wang8d8fc292011-05-19 21:39:10 +0000668 printk(KERN_CONT "released slaves\n");
669 break;
670 case NETDEV_JOIN:
671 printk(KERN_CONT "is joining a master device\n");
672 break;
673 }
674 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700675
Satyam Sharmab5427c22007-08-10 15:33:40 -0700676done:
Satyam Sharma17951f32007-08-10 15:33:01 -0700677 return NOTIFY_DONE;
678}
679
680static struct notifier_block netconsole_netdev_notifier = {
681 .notifier_call = netconsole_netdev_event,
682};
683
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684static void write_msg(struct console *con, const char *msg, unsigned int len)
685{
686 int frag, left;
687 unsigned long flags;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700688 struct netconsole_target *nt;
689 const char *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690
Satyam Sharmab5427c22007-08-10 15:33:40 -0700691 /* Avoid taking lock and disabling interrupts unnecessarily */
692 if (list_empty(&target_list))
693 return;
694
695 spin_lock_irqsave(&target_list_lock, flags);
696 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700697 netconsole_target_get(nt);
698 if (nt->enabled && netif_running(nt->np.dev)) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700699 /*
700 * We nest this inside the for-each-target loop above
701 * so that we're able to get as much logging out to
702 * at least one target if we die inside here, instead
703 * of unnecessarily keeping all targets in lock-step.
704 */
705 tmp = msg;
706 for (left = len; left;) {
707 frag = min(left, MAX_PRINT_CHUNK);
708 netpoll_send_udp(&nt->np, tmp, frag);
709 tmp += frag;
710 left -= frag;
711 }
Satyam Sharma0cc120be2007-08-10 15:30:31 -0700712 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700713 netconsole_target_put(nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700715 spin_unlock_irqrestore(&target_list_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716}
717
718static struct console netconsole = {
Satyam Sharmad39badf2007-08-10 15:27:24 -0700719 .name = "netcon",
Michael Ellerman0517dee2008-04-15 00:49:04 -0700720 .flags = CON_ENABLED,
Satyam Sharmad39badf2007-08-10 15:27:24 -0700721 .write = write_msg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722};
723
Satyam Sharmad39badf2007-08-10 15:27:24 -0700724static int __init init_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725{
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700726 int err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700727 struct netconsole_target *nt, *tmp;
728 unsigned long flags;
729 char *target_config;
730 char *input = config;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700731
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700732 if (strnlen(input, MAX_PARAM_LENGTH)) {
733 while ((target_config = strsep(&input, ";"))) {
734 nt = alloc_param_target(target_config);
735 if (IS_ERR(nt)) {
736 err = PTR_ERR(nt);
737 goto fail;
738 }
Michael Ellerman0517dee2008-04-15 00:49:04 -0700739 /* Dump existing printks when we register */
740 netconsole.flags |= CON_PRINTBUFFER;
741
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700742 spin_lock_irqsave(&target_list_lock, flags);
743 list_add(&nt->list, &target_list);
744 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700745 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700746 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Satyam Sharma17951f32007-08-10 15:33:01 -0700748 err = register_netdevice_notifier(&netconsole_netdev_notifier);
749 if (err)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700750 goto fail;
Satyam Sharma17951f32007-08-10 15:33:01 -0700751
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700752 err = dynamic_netconsole_init();
753 if (err)
754 goto undonotifier;
755
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 register_console(&netconsole);
757 printk(KERN_INFO "netconsole: network logging started\n");
Satyam Sharmad39badf2007-08-10 15:27:24 -0700758
Satyam Sharmad39badf2007-08-10 15:27:24 -0700759 return err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700760
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700761undonotifier:
762 unregister_netdevice_notifier(&netconsole_netdev_notifier);
763
Satyam Sharmab5427c22007-08-10 15:33:40 -0700764fail:
765 printk(KERN_ERR "netconsole: cleaning up\n");
766
767 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700768 * Remove all targets and destroy them (only targets created
769 * from the boot/module option exist here). Skipping the list
Satyam Sharmab5427c22007-08-10 15:33:40 -0700770 * lock is safe here, and netpoll_cleanup() will sleep.
771 */
772 list_for_each_entry_safe(nt, tmp, &target_list, list) {
773 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700774 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700775 }
776
777 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778}
779
Satyam Sharmad39badf2007-08-10 15:27:24 -0700780static void __exit cleanup_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700782 struct netconsole_target *nt, *tmp;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700783
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 unregister_console(&netconsole);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700785 dynamic_netconsole_exit();
Satyam Sharma17951f32007-08-10 15:33:01 -0700786 unregister_netdevice_notifier(&netconsole_netdev_notifier);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700787
788 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700789 * Targets created via configfs pin references on our module
790 * and would first be rmdir(2)'ed from userspace. We reach
791 * here only when they are already destroyed, and only those
792 * created from the boot/module option are left, so remove and
793 * destroy them. Skipping the list lock is safe here, and
794 * netpoll_cleanup() will sleep.
Satyam Sharmab5427c22007-08-10 15:33:40 -0700795 */
796 list_for_each_entry_safe(nt, tmp, &target_list, list) {
797 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700798 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700799 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800}
801
802module_init(init_netconsole);
803module_exit(cleanup_netconsole);