blob: 5ffbb88916473d45e6e60d1d3b57b22ec3651ee5 [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>
40#include <linux/console.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include <linux/moduleparam.h>
42#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <linux/netpoll.h>
Satyam Sharma0bcc1812007-08-10 15:35:05 -070044#include <linux/inet.h>
45#include <linux/configfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47MODULE_AUTHOR("Maintainer: Matt Mackall <mpm@selenic.com>");
48MODULE_DESCRIPTION("Console driver for network interfaces");
49MODULE_LICENSE("GPL");
50
Satyam Sharmad39badf2007-08-10 15:27:24 -070051#define MAX_PARAM_LENGTH 256
52#define MAX_PRINT_CHUNK 1000
53
54static char config[MAX_PARAM_LENGTH];
55module_param_string(netconsole, config, MAX_PARAM_LENGTH, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070056MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macaddr]\n");
57
Satyam Sharmad2b60882007-08-10 15:29:47 -070058#ifndef MODULE
59static int __init option_setup(char *opt)
60{
61 strlcpy(config, opt, MAX_PARAM_LENGTH);
62 return 1;
63}
64__setup("netconsole=", option_setup);
65#endif /* MODULE */
66
Satyam Sharmab5427c22007-08-10 15:33:40 -070067/* Linked list of all configured targets */
68static LIST_HEAD(target_list);
69
70/* This needs to be a spinlock because write_msg() cannot sleep */
71static DEFINE_SPINLOCK(target_list_lock);
72
Satyam Sharmadf180e32007-08-10 15:32:14 -070073/**
74 * struct netconsole_target - Represents a configured netconsole target.
Satyam Sharmab5427c22007-08-10 15:33:40 -070075 * @list: Links this target into the target_list.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070076 * @item: Links us into the configfs subsystem hierarchy.
77 * @enabled: On / off knob to enable / disable target.
78 * Visible from userspace (read-write).
79 * We maintain a strict 1:1 correspondence between this and
80 * whether the corresponding netpoll is active or inactive.
81 * Also, other parameters of a target may be modified at
82 * runtime only when it is disabled (enabled == 0).
Satyam Sharmadf180e32007-08-10 15:32:14 -070083 * @np: The netpoll structure for this target.
Satyam Sharma0bcc1812007-08-10 15:35:05 -070084 * Contains the other userspace visible parameters:
85 * dev_name (read-write)
86 * local_port (read-write)
87 * remote_port (read-write)
88 * local_ip (read-write)
89 * remote_ip (read-write)
90 * local_mac (read-only)
91 * remote_mac (read-write)
Satyam Sharmadf180e32007-08-10 15:32:14 -070092 */
93struct netconsole_target {
Satyam Sharmab5427c22007-08-10 15:33:40 -070094 struct list_head list;
Satyam Sharma0bcc1812007-08-10 15:35:05 -070095#ifdef CONFIG_NETCONSOLE_DYNAMIC
96 struct config_item item;
97#endif
98 int enabled;
Satyam Sharmadf180e32007-08-10 15:32:14 -070099 struct netpoll np;
100};
101
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700102#ifdef CONFIG_NETCONSOLE_DYNAMIC
103
104static struct configfs_subsystem netconsole_subsys;
105
106static int __init dynamic_netconsole_init(void)
107{
108 config_group_init(&netconsole_subsys.su_group);
109 mutex_init(&netconsole_subsys.su_mutex);
110 return configfs_register_subsystem(&netconsole_subsys);
111}
112
113static void __exit dynamic_netconsole_exit(void)
114{
115 configfs_unregister_subsystem(&netconsole_subsys);
116}
117
118/*
119 * Targets that were created by parsing the boot/module option string
120 * do not exist in the configfs hierarchy (and have NULL names) and will
121 * never go away, so make these a no-op for them.
122 */
123static void netconsole_target_get(struct netconsole_target *nt)
124{
125 if (config_item_name(&nt->item))
126 config_item_get(&nt->item);
127}
128
129static void netconsole_target_put(struct netconsole_target *nt)
130{
131 if (config_item_name(&nt->item))
132 config_item_put(&nt->item);
133}
134
135#else /* !CONFIG_NETCONSOLE_DYNAMIC */
136
137static int __init dynamic_netconsole_init(void)
138{
139 return 0;
140}
141
142static void __exit dynamic_netconsole_exit(void)
143{
144}
145
146/*
147 * No danger of targets going away from under us when dynamic
148 * reconfigurability is off.
149 */
150static void netconsole_target_get(struct netconsole_target *nt)
151{
152}
153
154static void netconsole_target_put(struct netconsole_target *nt)
155{
156}
157
158#endif /* CONFIG_NETCONSOLE_DYNAMIC */
159
160/* Allocate new target (from boot/module param) and setup netpoll for it */
161static struct netconsole_target *alloc_param_target(char *target_config)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700162{
163 int err = -ENOMEM;
164 struct netconsole_target *nt;
165
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700166 /*
167 * Allocate and initialize with defaults.
168 * Note that these targets get their config_item fields zeroed-out.
169 */
Satyam Sharmab5427c22007-08-10 15:33:40 -0700170 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
171 if (!nt) {
172 printk(KERN_ERR "netconsole: failed to allocate memory\n");
173 goto fail;
174 }
175
176 nt->np.name = "netconsole";
177 strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);
178 nt->np.local_port = 6665;
179 nt->np.remote_port = 6666;
180 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
181
182 /* Parse parameters and setup netpoll */
183 err = netpoll_parse_options(&nt->np, target_config);
184 if (err)
185 goto fail;
186
187 err = netpoll_setup(&nt->np);
188 if (err)
189 goto fail;
190
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700191 nt->enabled = 1;
192
Satyam Sharmab5427c22007-08-10 15:33:40 -0700193 return nt;
194
195fail:
196 kfree(nt);
197 return ERR_PTR(err);
198}
199
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700200/* Cleanup netpoll for given target (from boot/module param) and free it */
201static void free_param_target(struct netconsole_target *nt)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700202{
203 netpoll_cleanup(&nt->np);
204 kfree(nt);
205}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700207#ifdef CONFIG_NETCONSOLE_DYNAMIC
208
209/*
210 * Our subsystem hierarchy is:
211 *
212 * /sys/kernel/config/netconsole/
213 * |
214 * <target>/
215 * | enabled
216 * | dev_name
217 * | local_port
218 * | remote_port
219 * | local_ip
220 * | remote_ip
221 * | local_mac
222 * | remote_mac
223 * |
224 * <target>/...
225 */
226
227struct netconsole_target_attr {
228 struct configfs_attribute attr;
229 ssize_t (*show)(struct netconsole_target *nt,
230 char *buf);
231 ssize_t (*store)(struct netconsole_target *nt,
232 const char *buf,
233 size_t count);
234};
235
236static struct netconsole_target *to_target(struct config_item *item)
237{
238 return item ?
239 container_of(item, struct netconsole_target, item) :
240 NULL;
241}
242
243/*
244 * Wrapper over simple_strtol (base 10) with sanity and range checking.
245 * We return (signed) long only because we may want to return errors.
246 * Do not use this to convert numbers that are allowed to be negative.
247 */
248static long strtol10_check_range(const char *cp, long min, long max)
249{
250 long ret;
251 char *p = (char *) cp;
252
253 WARN_ON(min < 0);
254 WARN_ON(max < min);
255
256 ret = simple_strtol(p, &p, 10);
257
258 if (*p && (*p != '\n')) {
259 printk(KERN_ERR "netconsole: invalid input\n");
260 return -EINVAL;
261 }
262 if ((ret < min) || (ret > max)) {
263 printk(KERN_ERR "netconsole: input %ld must be between "
264 "%ld and %ld\n", ret, min, max);
265 return -EINVAL;
266 }
267
268 return ret;
269}
270
271/*
272 * Attribute operations for netconsole_target.
273 */
274
275static ssize_t show_enabled(struct netconsole_target *nt, char *buf)
276{
277 return snprintf(buf, PAGE_SIZE, "%d\n", nt->enabled);
278}
279
280static ssize_t show_dev_name(struct netconsole_target *nt, char *buf)
281{
282 return snprintf(buf, PAGE_SIZE, "%s\n", nt->np.dev_name);
283}
284
285static ssize_t show_local_port(struct netconsole_target *nt, char *buf)
286{
287 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.local_port);
288}
289
290static ssize_t show_remote_port(struct netconsole_target *nt, char *buf)
291{
292 return snprintf(buf, PAGE_SIZE, "%d\n", nt->np.remote_port);
293}
294
295static ssize_t show_local_ip(struct netconsole_target *nt, char *buf)
296{
297 return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
298 HIPQUAD(nt->np.local_ip));
299}
300
301static ssize_t show_remote_ip(struct netconsole_target *nt, char *buf)
302{
303 return snprintf(buf, PAGE_SIZE, "%d.%d.%d.%d\n",
304 HIPQUAD(nt->np.remote_ip));
305}
306
307static ssize_t show_local_mac(struct netconsole_target *nt, char *buf)
308{
Joe Perches0795af52007-10-03 17:59:30 -0700309 DECLARE_MAC_BUF(mac);
310 return snprintf(buf, PAGE_SIZE, "%s\n",
311 print_mac(mac, nt->np.local_mac));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700312}
313
314static ssize_t show_remote_mac(struct netconsole_target *nt, char *buf)
315{
Joe Perches0795af52007-10-03 17:59:30 -0700316 DECLARE_MAC_BUF(mac);
317 return snprintf(buf, PAGE_SIZE, "%s\n",
318 print_mac(mac, nt->np.remote_mac));
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700319}
320
321/*
322 * This one is special -- targets created through the configfs interface
323 * are not enabled (and the corresponding netpoll activated) by default.
324 * The user is expected to set the desired parameters first (which
325 * would enable him to dynamically add new netpoll targets for new
326 * network interfaces as and when they come up).
327 */
328static ssize_t store_enabled(struct netconsole_target *nt,
329 const char *buf,
330 size_t count)
331{
332 int err;
333 long enabled;
334
335 enabled = strtol10_check_range(buf, 0, 1);
336 if (enabled < 0)
337 return enabled;
338
339 if (enabled) { /* 1 */
340
341 /*
342 * Skip netpoll_parse_options() -- all the attributes are
343 * already configured via configfs. Just print them out.
344 */
345 netpoll_print_options(&nt->np);
346
347 err = netpoll_setup(&nt->np);
348 if (err)
349 return err;
350
351 printk(KERN_INFO "netconsole: network logging started\n");
352
353 } else { /* 0 */
354 netpoll_cleanup(&nt->np);
355 }
356
357 nt->enabled = enabled;
358
359 return strnlen(buf, count);
360}
361
362static ssize_t store_dev_name(struct netconsole_target *nt,
363 const char *buf,
364 size_t count)
365{
366 size_t len;
367
368 if (nt->enabled) {
369 printk(KERN_ERR "netconsole: target (%s) is enabled, "
370 "disable to update parameters\n",
371 config_item_name(&nt->item));
372 return -EINVAL;
373 }
374
375 strlcpy(nt->np.dev_name, buf, IFNAMSIZ);
376
377 /* Get rid of possible trailing newline from echo(1) */
378 len = strnlen(nt->np.dev_name, IFNAMSIZ);
379 if (nt->np.dev_name[len - 1] == '\n')
380 nt->np.dev_name[len - 1] = '\0';
381
382 return strnlen(buf, count);
383}
384
385static ssize_t store_local_port(struct netconsole_target *nt,
386 const char *buf,
387 size_t count)
388{
389 long local_port;
390#define __U16_MAX ((__u16) ~0U)
391
392 if (nt->enabled) {
393 printk(KERN_ERR "netconsole: target (%s) is enabled, "
394 "disable to update parameters\n",
395 config_item_name(&nt->item));
396 return -EINVAL;
397 }
398
399 local_port = strtol10_check_range(buf, 0, __U16_MAX);
400 if (local_port < 0)
401 return local_port;
402
403 nt->np.local_port = local_port;
404
405 return strnlen(buf, count);
406}
407
408static ssize_t store_remote_port(struct netconsole_target *nt,
409 const char *buf,
410 size_t count)
411{
412 long remote_port;
413#define __U16_MAX ((__u16) ~0U)
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
422 remote_port = strtol10_check_range(buf, 0, __U16_MAX);
423 if (remote_port < 0)
424 return remote_port;
425
426 nt->np.remote_port = remote_port;
427
428 return strnlen(buf, count);
429}
430
431static ssize_t store_local_ip(struct netconsole_target *nt,
432 const char *buf,
433 size_t count)
434{
435 if (nt->enabled) {
436 printk(KERN_ERR "netconsole: target (%s) is enabled, "
437 "disable to update parameters\n",
438 config_item_name(&nt->item));
439 return -EINVAL;
440 }
441
442 nt->np.local_ip = ntohl(in_aton(buf));
443
444 return strnlen(buf, count);
445}
446
447static ssize_t store_remote_ip(struct netconsole_target *nt,
448 const char *buf,
449 size_t count)
450{
451 if (nt->enabled) {
452 printk(KERN_ERR "netconsole: target (%s) is enabled, "
453 "disable to update parameters\n",
454 config_item_name(&nt->item));
455 return -EINVAL;
456 }
457
458 nt->np.remote_ip = ntohl(in_aton(buf));
459
460 return strnlen(buf, count);
461}
462
463static ssize_t store_remote_mac(struct netconsole_target *nt,
464 const char *buf,
465 size_t count)
466{
467 u8 remote_mac[ETH_ALEN];
468 char *p = (char *) buf;
469 int i;
470
471 if (nt->enabled) {
472 printk(KERN_ERR "netconsole: target (%s) is enabled, "
473 "disable to update parameters\n",
474 config_item_name(&nt->item));
475 return -EINVAL;
476 }
477
478 for (i = 0; i < ETH_ALEN - 1; i++) {
479 remote_mac[i] = simple_strtoul(p, &p, 16);
480 if (*p != ':')
481 goto invalid;
482 p++;
483 }
484 remote_mac[ETH_ALEN - 1] = simple_strtoul(p, &p, 16);
485 if (*p && (*p != '\n'))
486 goto invalid;
487
488 memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);
489
490 return strnlen(buf, count);
491
492invalid:
493 printk(KERN_ERR "netconsole: invalid input\n");
494 return -EINVAL;
495}
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
564 if (na->store)
565 ret = na->store(nt, buf, count);
566
567 return ret;
568}
569
570static struct configfs_item_operations netconsole_target_item_ops = {
571 .release = netconsole_target_release,
572 .show_attribute = netconsole_target_attr_show,
573 .store_attribute = netconsole_target_attr_store,
574};
575
576static struct config_item_type netconsole_target_type = {
577 .ct_attrs = netconsole_target_attrs,
578 .ct_item_ops = &netconsole_target_item_ops,
579 .ct_owner = THIS_MODULE,
580};
581
582/*
583 * Group operations and type for netconsole_subsys.
584 */
585
586static struct config_item *make_netconsole_target(struct config_group *group,
587 const char *name)
588{
589 unsigned long flags;
590 struct netconsole_target *nt;
591
592 /*
593 * Allocate and initialize with defaults.
594 * Target is disabled at creation (enabled == 0).
595 */
596 nt = kzalloc(sizeof(*nt), GFP_KERNEL);
597 if (!nt) {
598 printk(KERN_ERR "netconsole: failed to allocate memory\n");
599 return NULL;
600 }
601
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;
606 memset(nt->np.remote_mac, 0xff, ETH_ALEN);
607
608 /* Initialize the config_item member */
609 config_item_init_type_name(&nt->item, name, &netconsole_target_type);
610
611 /* Adding, but it is disabled */
612 spin_lock_irqsave(&target_list_lock, flags);
613 list_add(&nt->list, &target_list);
614 spin_unlock_irqrestore(&target_list_lock, flags);
615
616 return &nt->item;
617}
618
619static void drop_netconsole_target(struct config_group *group,
620 struct config_item *item)
621{
622 unsigned long flags;
623 struct netconsole_target *nt = to_target(item);
624
625 spin_lock_irqsave(&target_list_lock, flags);
626 list_del(&nt->list);
627 spin_unlock_irqrestore(&target_list_lock, flags);
628
629 /*
630 * The target may have never been enabled, or was manually disabled
631 * before being removed so netpoll may have already been cleaned up.
632 */
633 if (nt->enabled)
634 netpoll_cleanup(&nt->np);
635
636 config_item_put(&nt->item);
637}
638
639static struct configfs_group_operations netconsole_subsys_group_ops = {
640 .make_item = make_netconsole_target,
641 .drop_item = drop_netconsole_target,
642};
643
644static struct config_item_type netconsole_subsys_type = {
645 .ct_group_ops = &netconsole_subsys_group_ops,
646 .ct_owner = THIS_MODULE,
647};
648
649/* The netconsole configfs subsystem */
650static struct configfs_subsystem netconsole_subsys = {
651 .su_group = {
652 .cg_item = {
653 .ci_namebuf = "netconsole",
654 .ci_type = &netconsole_subsys_type,
655 },
656 },
657};
658
659#endif /* CONFIG_NETCONSOLE_DYNAMIC */
660
Satyam Sharma17951f32007-08-10 15:33:01 -0700661/* Handle network interface device notifications */
662static int netconsole_netdev_event(struct notifier_block *this,
663 unsigned long event,
664 void *ptr)
665{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700666 unsigned long flags;
667 struct netconsole_target *nt;
Satyam Sharma17951f32007-08-10 15:33:01 -0700668 struct net_device *dev = ptr;
Satyam Sharma17951f32007-08-10 15:33:01 -0700669
Satyam Sharmab5427c22007-08-10 15:33:40 -0700670 if (!(event == NETDEV_CHANGEADDR || event == NETDEV_CHANGENAME))
671 goto done;
Satyam Sharma17951f32007-08-10 15:33:01 -0700672
Satyam Sharmab5427c22007-08-10 15:33:40 -0700673 spin_lock_irqsave(&target_list_lock, flags);
674 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700675 netconsole_target_get(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700676 if (nt->np.dev == dev) {
677 switch (event) {
678 case NETDEV_CHANGEADDR:
679 memcpy(nt->np.local_mac, dev->dev_addr, ETH_ALEN);
680 break;
681
682 case NETDEV_CHANGENAME:
683 strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
684 break;
685 }
Satyam Sharma17951f32007-08-10 15:33:01 -0700686 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700687 netconsole_target_put(nt);
Satyam Sharma17951f32007-08-10 15:33:01 -0700688 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700689 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharma17951f32007-08-10 15:33:01 -0700690
Satyam Sharmab5427c22007-08-10 15:33:40 -0700691done:
Satyam Sharma17951f32007-08-10 15:33:01 -0700692 return NOTIFY_DONE;
693}
694
695static struct notifier_block netconsole_netdev_notifier = {
696 .notifier_call = netconsole_netdev_event,
697};
698
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699static void write_msg(struct console *con, const char *msg, unsigned int len)
700{
701 int frag, left;
702 unsigned long flags;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700703 struct netconsole_target *nt;
704 const char *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
Satyam Sharmab5427c22007-08-10 15:33:40 -0700706 /* Avoid taking lock and disabling interrupts unnecessarily */
707 if (list_empty(&target_list))
708 return;
709
710 spin_lock_irqsave(&target_list_lock, flags);
711 list_for_each_entry(nt, &target_list, list) {
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700712 netconsole_target_get(nt);
713 if (nt->enabled && netif_running(nt->np.dev)) {
Satyam Sharmab5427c22007-08-10 15:33:40 -0700714 /*
715 * We nest this inside the for-each-target loop above
716 * so that we're able to get as much logging out to
717 * at least one target if we die inside here, instead
718 * of unnecessarily keeping all targets in lock-step.
719 */
720 tmp = msg;
721 for (left = len; left;) {
722 frag = min(left, MAX_PRINT_CHUNK);
723 netpoll_send_udp(&nt->np, tmp, frag);
724 tmp += frag;
725 left -= frag;
726 }
Satyam Sharma0cc120be2007-08-10 15:30:31 -0700727 }
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700728 netconsole_target_put(nt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700730 spin_unlock_irqrestore(&target_list_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731}
732
733static struct console netconsole = {
Satyam Sharmad39badf2007-08-10 15:27:24 -0700734 .name = "netcon",
735 .flags = CON_ENABLED | CON_PRINTBUFFER,
736 .write = write_msg,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737};
738
Satyam Sharmad39badf2007-08-10 15:27:24 -0700739static int __init init_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740{
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700741 int err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700742 struct netconsole_target *nt, *tmp;
743 unsigned long flags;
744 char *target_config;
745 char *input = config;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700746
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700747 if (strnlen(input, MAX_PARAM_LENGTH)) {
748 while ((target_config = strsep(&input, ";"))) {
749 nt = alloc_param_target(target_config);
750 if (IS_ERR(nt)) {
751 err = PTR_ERR(nt);
752 goto fail;
753 }
754 spin_lock_irqsave(&target_list_lock, flags);
755 list_add(&nt->list, &target_list);
756 spin_unlock_irqrestore(&target_list_lock, flags);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700757 }
Satyam Sharmab5427c22007-08-10 15:33:40 -0700758 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759
Satyam Sharma17951f32007-08-10 15:33:01 -0700760 err = register_netdevice_notifier(&netconsole_netdev_notifier);
761 if (err)
Satyam Sharmab5427c22007-08-10 15:33:40 -0700762 goto fail;
Satyam Sharma17951f32007-08-10 15:33:01 -0700763
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700764 err = dynamic_netconsole_init();
765 if (err)
766 goto undonotifier;
767
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 register_console(&netconsole);
769 printk(KERN_INFO "netconsole: network logging started\n");
Satyam Sharmad39badf2007-08-10 15:27:24 -0700770
Satyam Sharmad39badf2007-08-10 15:27:24 -0700771 return err;
Satyam Sharmab5427c22007-08-10 15:33:40 -0700772
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700773undonotifier:
774 unregister_netdevice_notifier(&netconsole_netdev_notifier);
775
Satyam Sharmab5427c22007-08-10 15:33:40 -0700776fail:
777 printk(KERN_ERR "netconsole: cleaning up\n");
778
779 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700780 * Remove all targets and destroy them (only targets created
781 * from the boot/module option exist here). Skipping the list
Satyam Sharmab5427c22007-08-10 15:33:40 -0700782 * lock is safe here, and netpoll_cleanup() will sleep.
783 */
784 list_for_each_entry_safe(nt, tmp, &target_list, list) {
785 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700786 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700787 }
788
789 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790}
791
Satyam Sharmad39badf2007-08-10 15:27:24 -0700792static void __exit cleanup_netconsole(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793{
Satyam Sharmab5427c22007-08-10 15:33:40 -0700794 struct netconsole_target *nt, *tmp;
Satyam Sharmadf180e32007-08-10 15:32:14 -0700795
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 unregister_console(&netconsole);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700797 dynamic_netconsole_exit();
Satyam Sharma17951f32007-08-10 15:33:01 -0700798 unregister_netdevice_notifier(&netconsole_netdev_notifier);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700799
800 /*
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700801 * Targets created via configfs pin references on our module
802 * and would first be rmdir(2)'ed from userspace. We reach
803 * here only when they are already destroyed, and only those
804 * created from the boot/module option are left, so remove and
805 * destroy them. Skipping the list lock is safe here, and
806 * netpoll_cleanup() will sleep.
Satyam Sharmab5427c22007-08-10 15:33:40 -0700807 */
808 list_for_each_entry_safe(nt, tmp, &target_list, list) {
809 list_del(&nt->list);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700810 free_param_target(nt);
Satyam Sharmab5427c22007-08-10 15:33:40 -0700811 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812}
813
814module_init(init_netconsole);
815module_exit(cleanup_netconsole);