blob: 94255f09093d670695de61b00a07b818371844a0 [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/*
245 * Wrapper over simple_strtol (base 10) with sanity and range checking.
246 * We return (signed) long only because we may want to return errors.
247 * Do not use this to convert numbers that are allowed to be negative.
248 */
249static long strtol10_check_range(const char *cp, long min, long max)
250{
251 long ret;
252 char *p = (char *) cp;
253
254 WARN_ON(min < 0);
255 WARN_ON(max < min);
256
257 ret = simple_strtol(p, &p, 10);
258
259 if (*p && (*p != '\n')) {
260 printk(KERN_ERR "netconsole: invalid input\n");
261 return -EINVAL;
262 }
263 if ((ret < min) || (ret > max)) {
264 printk(KERN_ERR "netconsole: input %ld must be between "
265 "%ld and %ld\n", ret, min, max);
266 return -EINVAL;
267 }
268
269 return ret;
270}
271
272/*
273 * Attribute operations for netconsole_target.
274 */
275
276static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
277{
278 return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
279}
280
281static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
282{
283 return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
284}
285
286static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
287{
288 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
289}
290
291static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
292{
293 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
294}
295
296static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
297{
Harvey Harrisone7557af2009-03-28 15:38:31 +0000298 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700299}
300
301static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
302{
Harvey Harrisone7557af2009-03-28 15:38:31 +0000303 return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700304}
305
306static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
307{
Stephen Hemminger09538642007-11-19 19:23:29 -0800308 struct net_device *dev = nt->np.dev;
Johannes Berge1749612008-10-27 15:59:26 -0700309 static const u8 bcast[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
Stephen Hemminger09538642007-11-19 19:23:29 -0800310
Johannes Berge1749612008-10-27 15:59:26 -0700311 return snprintf(buf, PAGE_SIZE, "%pM\n", dev ? dev->dev_addr : bcast);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700312}
313
314static ssize_t show_remote_mac(struct netconsole_target *nt, char *buf)
315{
Johannes Berge1749612008-10-27 15:59:26 -0700316 return snprintf(buf, PAGE_SIZE, "%pM\n", nt->np.remote_mac);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700317}
318
319/*
320 * This one is special -- targets created through the configfs interface
321 * are not enabled (and the corresponding netpoll activated) by default.
322 * The user is expected to set the desired parameters first (which
323 * would enable him to dynamically add new netpoll targets for new
324 * network interfaces as and when they come up).
325 */
326static ssize_t store_enabled(struct netconsole_target *nt,
327 const char *buf,
328 size_t count)
329{
330 int err;
331 long enabled;
332
333 enabled = strtol10_check_range(buf, 0, 1);
334 if (enabled < 0)
335 return enabled;
336
337 if (enabled) { /* 1 */
338
339 /*
340 * Skip netpoll_parse_options() -- all the attributes are
341 * already configured via configfs. Just print them out.
342 */
343 netpoll_print_options(&nt->np);
344
345 err = netpoll_setup(&nt->np);
346 if (err)
347 return err;
348
349 printk(KERN_INFO "netconsole: network logging started\n");
350
351 } else { /* 0 */
352 netpoll_cleanup(&nt->np);
353 }
354
355 nt->enabled = enabled;
356
357 return strnlen(buf, count);
358}
359
360static ssize_t store_dev_name(struct netconsole_target *nt,
361 const char *buf,
362 size_t count)
363{
364 size_t len;
365
366 if (nt->enabled) {
367 printk(KERN_ERR "netconsole: target (%s) is enabled, "
368 "disable to update parameters\n",
369 config_item_name(&nt->item));
370 return -EINVAL;
371 }
372
373 strlcpy(nt->np.dev_name, buf, IFNAMSIZ);
374
375 /* Get rid of possible trailing newline from echo(1) */
376 len = strnlen(nt->np.dev_name, IFNAMSIZ);
377 if (nt->np.dev_name[len - 1] == '\n')
378 nt->np.dev_name[len - 1] = '\0';
379
380 return strnlen(buf, count);
381}
382
383static ssize_t store_local_port(struct netconsole_target *nt,
384 const char *buf,
385 size_t count)
386{
387 long local_port;
388#define __U16_MAX ((__u16) ~0U)
389
390 if (nt->enabled) {
391 printk(KERN_ERR "netconsole: target (%s) is enabled, "
392 "disable to update parameters\n",
393 config_item_name(&nt->item));
394 return -EINVAL;
395 }
396
397 local_port = strtol10_check_range(buf, 0, __U16_MAX);
398 if (local_port < 0)
399 return local_port;
400
401 nt->np.local_port = local_port;
402
403 return strnlen(buf, count);
404}
405
406static ssize_t store_remote_port(struct netconsole_target *nt,
407 const char *buf,
408 size_t count)
409{
410 long remote_port;
411#define __U16_MAX ((__u16) ~0U)
412
413 if (nt->enabled) {
414 printk(KERN_ERR "netconsole: target (%s) is enabled, "
415 "disable to update parameters\n",
416 config_item_name(&nt->item));
417 return -EINVAL;
418 }
419
420 remote_port = strtol10_check_range(buf, 0, __U16_MAX);
421 if (remote_port < 0)
422 return remote_port;
423
424 nt->np.remote_port = remote_port;
425
426 return strnlen(buf, count);
427}
428
429static ssize_t store_local_ip(struct netconsole_target *nt,
430 const char *buf,
431 size_t count)
432{
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
Harvey Harrisone7557af2009-03-28 15:38:31 +0000440 nt->np.local_ip = in_aton(buf);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700441
442 return strnlen(buf, count);
443}
444
445static ssize_t store_remote_ip(struct netconsole_target *nt,
446 const char *buf,
447 size_t count)
448{
449 if (nt->enabled) {
450 printk(KERN_ERR "netconsole: target (%s) is enabled, "
451 "disable to update parameters\n",
452 config_item_name(&nt->item));
453 return -EINVAL;
454 }
455
Harvey Harrisone7557af2009-03-28 15:38:31 +0000456 nt->np.remote_ip = in_aton(buf);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700457
458 return strnlen(buf, count);
459}
460
461static ssize_t store_remote_mac(struct netconsole_target *nt,
462 const char *buf,
463 size_t count)
464{
465 u8 remote_mac[ETH_ALEN];
466 char *p = (char *) buf;
467 int i;
468
469 if (nt->enabled) {
470 printk(KERN_ERR "netconsole: target (%s) is enabled, "
471 "disable to update parameters\n",
472 config_item_name(&nt->item));
473 return -EINVAL;
474 }
475
476 for (i = 0; i < ETH_ALEN - 1; i++) {
477 remote_mac[i] = simple_strtoul(p, &p, 16);
478 if (*p != ':')
479 goto invalid;
480 p++;
481 }
482 remote_mac[ETH_ALEN - 1] = simple_strtoul(p, &p, 16);
483 if (*p && (*p != '\n'))
484 goto invalid;
485
486 memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
487
488 return strnlen(buf, count);
489
490invalid:
491 printk(KERN_ERR "netconsole: invalid input\n");
492 return -EINVAL;
493}
494
495/*
496 * Attribute definitions for netconsole_target.
497 */
498
499#define NETCONSOLE_TARGET_ATTR_RO(_name) \
500static struct netconsole_target_attr netconsole_target_##_name = \
501 __CONFIGFS_ATTR(_name, S_IRUGO, show_##_name, NULL)
502
503#define NETCONSOLE_TARGET_ATTR_RW(_name) \
504static struct netconsole_target_attr netconsole_target_##_name = \
505 __CONFIGFS_ATTR(_name, S_IRUGO | S_IWUSR, show_##_name, store_##_name)
506
507NETCONSOLE_TARGET_ATTR_RW(enabled);
508NETCONSOLE_TARGET_ATTR_RW(dev_name);
509NETCONSOLE_TARGET_ATTR_RW(local_port);
510NETCONSOLE_TARGET_ATTR_RW(remote_port);
511NETCONSOLE_TARGET_ATTR_RW(local_ip);
512NETCONSOLE_TARGET_ATTR_RW(remote_ip);
513NETCONSOLE_TARGET_ATTR_RO(local_mac);
514NETCONSOLE_TARGET_ATTR_RW(remote_mac);
515
516static struct configfs_attribute *netconsole_target_attrs[] = {
517 &netconsole_target_enabled.attr,
518 &netconsole_target_dev_name.attr,
519 &netconsole_target_local_port.attr,
520 &netconsole_target_remote_port.attr,
521 &netconsole_target_local_ip.attr,
522 &netconsole_target_remote_ip.attr,
523 &netconsole_target_local_mac.attr,
524 &netconsole_target_remote_mac.attr,
525 NULL,
526};
527
528/*
529 * Item operations and type for netconsole_target.
530 */
531
532static void netconsole_target_release(struct config_item *item)
533{
534 kfree(to_target(item));
535}
536
537static ssize_t netconsole_target_attr_show(struct config_item *item,
538 struct configfs_attribute *attr,
539 char *buf)
540{
541 ssize_t ret = -EINVAL;
542 struct netconsole_target *nt = to_target(item);
543 struct netconsole_target_attr *na =
544 container_of(attr, struct netconsole_target_attr, attr);
545
546 if (na->show)
547 ret = na->show(nt, buf);
548
549 return ret;
550}
551
552static ssize_t netconsole_target_attr_store(struct config_item *item,
553 struct configfs_attribute *attr,
554 const char *buf,
555 size_t count)
556{
557 ssize_t ret = -EINVAL;
558 struct netconsole_target *nt = to_target(item);
559 struct netconsole_target_attr *na =
560 container_of(attr, struct netconsole_target_attr, attr);
561
562 if (na->store)
563 ret = na->store(nt, buf, count);
564
565 return ret;
566}
567
568static struct configfs_item_operations netconsole_target_item_ops = {
569 .release = netconsole_target_release,
570 .show_attribute = netconsole_target_attr_show,
571 .store_attribute = netconsole_target_attr_store,
572};
573
574static struct config_item_type netconsole_target_type = {
575 .ct_attrs = netconsole_target_attrs,
576 .ct_item_ops = &netconsole_target_item_ops,
577 .ct_owner = THIS_MODULE,
578};
579
580/*
581 * Group operations and type for netconsole_subsys.
582 */
583
Joel Beckerf89ab862008-07-17 14:53:48 -0700584static struct config_item *make_netconsole_target(struct config_group *group,
585 const char *name)
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700586{
587 unsigned long flags;
588 struct netconsole_target *nt;
589
590 /*
591 * Allocate and initialize with defaults.
592 * Target is disabled at creation (enabled == 0).
593 */
594 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
595 if (!nt) {
596 printk(KERN_ERR "netconsole: failed to allocate memory\n");
Joel Beckera6795e92008-07-17 15:21:29 -0700597 return ERR_PTR(-ENOMEM);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700598 }
599
600 nt->np.name = "netconsole";
601 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
602 nt->np.local_port = 6665;
603 nt->np.remote_port = 6666;
604 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
605
606 /* Initialize the config_item member */
607 config_item_init_type_name(&nt->item, name, &netconsole_target_type);
608
609 /* Adding, but it is disabled */
610 spin_lock_irqsave(&target_list_lock, flags);
611 list_add(&nt->list, &target_list);
612 spin_unlock_irqrestore(&target_list_lock, flags);
613
Joel Beckerf89ab862008-07-17 14:53:48 -0700614 return &nt->item;
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700615}
616
617static void drop_netconsole_target(struct config_group *group,
618 struct config_item *item)
619{
620 unsigned long flags;
621 struct netconsole_target *nt = to_target(item);
622
623 spin_lock_irqsave(&target_list_lock, flags);
624 list_del(&nt->list);
625 spin_unlock_irqrestore(&target_list_lock, flags);
626
627 /*
628 * The target may have never been enabled, or was manually disabled
629 * before being removed so netpoll may have already been cleaned up.
630 */
631 if (nt->enabled)
632 netpoll_cleanup(&nt->np);
633
634 config_item_put(&nt->item);
635}
636
637static struct configfs_group_operations netconsole_subsys_group_ops = {
638 .make_item = make_netconsole_target,
639 .drop_item = drop_netconsole_target,
640};
641
642static struct config_item_type netconsole_subsys_type = {
643 .ct_group_ops = &netconsole_subsys_group_ops,
644 .ct_owner = THIS_MODULE,
645};
646
647/* The netconsole configfs subsystem */
648static struct configfs_subsystem netconsole_subsys = {
649 .su_group = {
650 .cg_item = {
651 .ci_namebuf = "netconsole",
652 .ci_type = &netconsole_subsys_type,
653 },
654 },
655};
656
657#endif /* CONFIG_NETCONSOLE_DYNAMIC */
658
Satyam Sharma17951f32007-08-10 15:33:01 -0700659/* Handle network interface device notifications */
660static int netconsole_netdev_event(struct notifier_block *this,
661 unsigned long event,
662 void *ptr)
663{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700664 unsigned long flags;
665 struct netconsole_target *nt;
Satyam Sharma17951f32007-08-10 15:33:01 -0700666 struct net_device *dev = ptr;
Satyam Sharma17951f32007-08-10 15:33:01 -0700667
WANG Cong0e34e932010-05-06 00:47:21 -0700668 if (!(event == NETDEV_CHANGENAME || event == NETDEV_UNREGISTER ||
669 event == NETDEV_BONDING_DESLAVE || event == NETDEV_GOING_DOWN))
Satyam Sharmab5427c22007-08-10 15:33:40 -0700670 goto done;
Satyam Sharma17951f32007-08-10 15:33:01 -0700671
Satyam Sharmab5427c22007-08-10 15:33:40 -0700672 spin_lock_irqsave(&target_list_lock, flags);
673 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700674 netconsole_target_get(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700675 if (nt->np.dev == dev) {
676 switch (event) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700677 case NETDEV_CHANGENAME:
678 strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
679 break;
Bruno Prémont2382b152009-04-29 20:45:17 +0000680 case NETDEV_UNREGISTER:
Neil Horman3b410a32010-10-13 16:01:52 +0000681 /*
682 * rtnl_lock already held
683 */
684 if (nt->np.dev) {
685 __netpoll_cleanup(&nt->np);
686 dev_put(nt->np.dev);
687 nt->np.dev = NULL;
688 }
WANG Cong0e34e932010-05-06 00:47:21 -0700689 /* Fall through */
690 case NETDEV_GOING_DOWN:
691 case NETDEV_BONDING_DESLAVE:
Bruno Prémont2382b152009-04-29 20:45:17 +0000692 nt->enabled = 0;
Bruno Prémont2382b152009-04-29 20:45:17 +0000693 break;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700694 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700695 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700696 netconsole_target_put(nt);
Satyam Sharma17951f32007-08-10 15:33:01 -0700697 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700698 spin_unlock_irqrestore(&target_list_lock, flags);
WANG Cong0e34e932010-05-06 00:47:21 -0700699 if (event == NETDEV_UNREGISTER || event == NETDEV_BONDING_DESLAVE)
700 printk(KERN_INFO "netconsole: network logging stopped, "
701 "interface %s %s\n", dev->name,
702 event == NETDEV_UNREGISTER ? "unregistered" : "released slaves");
Satyam Sharma17951f32007-08-10 15:33:01 -0700703
Satyam Sharmab5427c22007-08-10 15:33:40 -0700704done:
Satyam Sharma17951f32007-08-10 15:33:01 -0700705 return NOTIFY_DONE;
706}
707
708static struct notifier_block netconsole_netdev_notifier = {
709 .notifier_call = netconsole_netdev_event,
710};
711
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712static void write_msg(struct console *con, const char *msg, unsigned int len)
713{
714 int frag, left;
715 unsigned long flags;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700716 struct netconsole_target *nt;
717 const char *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718
Satyam Sharmab5427c22007-08-10 15:33:40 -0700719 /* Avoid taking lock and disabling interrupts unnecessarily */
720 if (list_empty(&target_list))
721 return;
722
723 spin_lock_irqsave(&target_list_lock, flags);
724 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700725 netconsole_target_get(nt);
726 if (nt->enabled && netif_running(nt->np.dev)) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700727 /*
728 * We nest this inside the for-each-target loop above
729 * so that we're able to get as much logging out to
730 * at least one target if we die inside here, instead
731 * of unnecessarily keeping all targets in lock-step.
732 */
733 tmp = msg;
734 for (left = len; left;) {
735 frag = min(left, MAX_PRINT_CHUNK);
736 netpoll_send_udp(&nt->np, tmp, frag);
737 tmp += frag;
738 left -= frag;
739 }
Satyam Sharma0cc120be2007-08-10 15:30:31 -0700740 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700741 netconsole_target_put(nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700743 spin_unlock_irqrestore(&target_list_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744}
745
746static struct console netconsole = {
Satyam Sharmad39badf2007-08-10 15:27:24 -0700747 .name = "netcon",
Michael Ellerman0517dee2008-04-15 00:49:04 -0700748 .flags = CON_ENABLED,
Satyam Sharmad39badf2007-08-10 15:27:24 -0700749 .write = write_msg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750};
751
Satyam Sharmad39badf2007-08-10 15:27:24 -0700752static int __init init_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753{
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700754 int err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700755 struct netconsole_target *nt, *tmp;
756 unsigned long flags;
757 char *target_config;
758 char *input = config;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700759
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700760 if (strnlen(input, MAX_PARAM_LENGTH)) {
761 while ((target_config = strsep(&input, ";"))) {
762 nt = alloc_param_target(target_config);
763 if (IS_ERR(nt)) {
764 err = PTR_ERR(nt);
765 goto fail;
766 }
Michael Ellerman0517dee2008-04-15 00:49:04 -0700767 /* Dump existing printks when we register */
768 netconsole.flags |= CON_PRINTBUFFER;
769
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700770 spin_lock_irqsave(&target_list_lock, flags);
771 list_add(&nt->list, &target_list);
772 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700773 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700774 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775
Satyam Sharma17951f32007-08-10 15:33:01 -0700776 err = register_netdevice_notifier(&netconsole_netdev_notifier);
777 if (err)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700778 goto fail;
Satyam Sharma17951f32007-08-10 15:33:01 -0700779
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700780 err = dynamic_netconsole_init();
781 if (err)
782 goto undonotifier;
783
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 register_console(&netconsole);
785 printk(KERN_INFO "netconsole: network logging started\n");
Satyam Sharmad39badf2007-08-10 15:27:24 -0700786
Satyam Sharmad39badf2007-08-10 15:27:24 -0700787 return err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700788
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700789undonotifier:
790 unregister_netdevice_notifier(&netconsole_netdev_notifier);
791
Satyam Sharmab5427c22007-08-10 15:33:40 -0700792fail:
793 printk(KERN_ERR "netconsole: cleaning up\n");
794
795 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700796 * Remove all targets and destroy them (only targets created
797 * from the boot/module option exist here). Skipping the list
Satyam Sharmab5427c22007-08-10 15:33:40 -0700798 * lock is safe here, and netpoll_cleanup() will sleep.
799 */
800 list_for_each_entry_safe(nt, tmp, &target_list, list) {
801 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700802 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700803 }
804
805 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806}
807
Satyam Sharmad39badf2007-08-10 15:27:24 -0700808static void __exit cleanup_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700810 struct netconsole_target *nt, *tmp;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700811
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 unregister_console(&netconsole);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700813 dynamic_netconsole_exit();
Satyam Sharma17951f32007-08-10 15:33:01 -0700814 unregister_netdevice_notifier(&netconsole_netdev_notifier);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700815
816 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700817 * Targets created via configfs pin references on our module
818 * and would first be rmdir(2)'ed from userspace. We reach
819 * here only when they are already destroyed, and only those
820 * created from the boot/module option are left, so remove and
821 * destroy them. Skipping the list lock is safe here, and
822 * netpoll_cleanup() will sleep.
Satyam Sharmab5427c22007-08-10 15:33:40 -0700823 */
824 list_for_each_entry_safe(nt, tmp, &target_list, list) {
825 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700826 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700827 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828}
829
830module_init(init_netconsole);
831module_exit(cleanup_netconsole);