[linux-block.git] / include / linux / kmsg_dump.h

/*
 * linux/include/kmsg_dump.h
 *
 * Copyright (C) 2009 Net Insight AB
 *
 * Author: Simon Kagstrom <simon.kagstrom@netinsight.net>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */
#ifndef _LINUX_KMSG_DUMP_H
#define _LINUX_KMSG_DUMP_H

#include <linux/errno.h>
#include <linux/list.h>

/*
 * Keep this list arranged in rough order of priority. Anything listed after
 * KMSG_DUMP_OOPS will not be logged by default unless printk.always_kmsg_dump
 * is passed to the kernel.
 */
enum kmsg_dump_reason {
	KMSG_DUMP_UNDEF,
	KMSG_DUMP_PANIC,
	KMSG_DUMP_OOPS,
	KMSG_DUMP_EMERG,
	KMSG_DUMP_SHUTDOWN,
	KMSG_DUMP_MAX
};

/**
 * struct kmsg_dump_iter - iterator for retrieving kernel messages
 * @cur_seq:	Points to the oldest message to dump
 * @next_seq:	Points after the newest message to dump
 */
struct kmsg_dump_iter {
	u64	cur_seq;
	u64	next_seq;
};

/**
 * struct kmsg_dumper - kernel crash message dumper structure
 * @list:	Entry in the dumper list (private)
 * @dump:	Call into dumping code which will retrieve the data with
 * 		through the record iterator
 * @max_reason:	filter for highest reason number that should be dumped
 * @registered:	Flag that specifies if this is already registered
 */
struct kmsg_dumper {
	struct list_head list;
	void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
	enum kmsg_dump_reason max_reason;
	bool registered;
};

#ifdef CONFIG_PRINTK
void kmsg_dump(enum kmsg_dump_reason reason);

bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
			char *line, size_t size, size_t *len);

bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
			  char *buf, size_t size, size_t *len_out);

void kmsg_dump_rewind(struct kmsg_dump_iter *iter);

int kmsg_dump_register(struct kmsg_dumper *dumper);

int kmsg_dump_unregister(struct kmsg_dumper *dumper);

const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason);
#else
static inline void kmsg_dump(enum kmsg_dump_reason reason)
{
}

static inline bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
				const char *line, size_t size, size_t *len)
{
	return false;
}

static inline bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
					char *buf, size_t size, size_t *len)
{
	return false;
}

static inline void kmsg_dump_rewind(struct kmsg_dump_iter *iter)
{
}

static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
{
	return -EINVAL;
}

static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
{
	return -EINVAL;
}

static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
{
	return "Disabled";
}
#endif

#endif /* _LINUX_KMSG_DUMP_H */
Commit	Line	Data
456b565c SK	1	/*
	2	* linux/include/kmsg_dump.h
	3	*
	4	* Copyright (C) 2009 Net Insight AB
	5	*
	6	* Author: Simon Kagstrom <simon.kagstrom@netinsight.net>
	7	*
	8	* This file is subject to the terms and conditions of the GNU General Public
	9	* License. See the file COPYING in the main directory of this archive
	10	* for more details.
	11	*/
	12	#ifndef _LINUX_KMSG_DUMP_H
	13	#define _LINUX_KMSG_DUMP_H
	14
ac562241	15	#include <linux/errno.h>
456b565c SK	16	#include <linux/list.h>
456b565c SK	17
c22ab332 MG	18	/*
	19	* Keep this list arranged in rough order of priority. Anything listed after
	20	* KMSG_DUMP_OOPS will not be logged by default unless printk.always_kmsg_dump
	21	* is passed to the kernel.
	22	*/
456b565c	23	enum kmsg_dump_reason {
e2ae715d	24	KMSG_DUMP_UNDEF,
456b565c	25	KMSG_DUMP_PANIC,
c22ab332 MG	26	KMSG_DUMP_OOPS,
c22ab332 MG	27	KMSG_DUMP_EMERG,
6d3cf962	28	KMSG_DUMP_SHUTDOWN,
b1f6f161	29	KMSG_DUMP_MAX
456b565c SK	30	};
456b565c SK	31
f9f3f02d JO	32	/**
	33	* struct kmsg_dump_iter - iterator for retrieving kernel messages
	34	* @cur_seq: Points to the oldest message to dump
	35	* @next_seq: Points after the newest message to dump
	36	*/
	37	struct kmsg_dump_iter {
	38	u64 cur_seq;
	39	u64 next_seq;
	40	};
	41
456b565c SK	42	/**
456b565c SK	43	* struct kmsg_dumper - kernel crash message dumper structure
456b565c	44	* @list: Entry in the dumper list (private)
e2ae715d KS	45	* @dump: Call into dumping code which will retrieve the data with
	46	* through the record iterator
	47	* @max_reason: filter for highest reason number that should be dumped
456b565c SK	48	* @registered: Flag that specifies if this is already registered
	49	*/
	50	struct kmsg_dumper {
456b565c	51	struct list_head list;
e2ae715d KS	52	void (dump)(struct kmsg_dumper dumper, enum kmsg_dump_reason reason);
e2ae715d KS	53	enum kmsg_dump_reason max_reason;
e2ae715d	54	bool registered;
456b565c SK	55	};
456b565c SK	56
595dd3d8	57	#ifdef CONFIG_PRINTK
456b565c SK	58	void kmsg_dump(enum kmsg_dump_reason reason);
456b565c SK	59
f9f3f02d	60	bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
e2ae715d KS	61	char line, size_t size, size_t len);
e2ae715d KS	62
f9f3f02d	63	bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
726b5097	64	char buf, size_t size, size_t len_out);
e2ae715d	65
f9f3f02d	66	void kmsg_dump_rewind(struct kmsg_dump_iter *iter);
e2ae715d	67
456b565c SK	68	int kmsg_dump_register(struct kmsg_dumper *dumper);
	69
	70	int kmsg_dump_unregister(struct kmsg_dumper *dumper);
fb13cb8a KC	71
fb13cb8a KC	72	const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason);
595dd3d8 RD	73	#else
	74	static inline void kmsg_dump(enum kmsg_dump_reason reason)
	75	{
	76	}
	77
f9f3f02d	78	static inline bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
246f6f2f	79	const char line, size_t size, size_t len)
e2ae715d KS	80	{
	81	return false;
	82	}
	83
f9f3f02d	84	static inline bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
246f6f2f	85	char buf, size_t size, size_t len)
e2ae715d KS	86	{
	87	return false;
	88	}
	89
f9f3f02d	90	static inline void kmsg_dump_rewind(struct kmsg_dump_iter *iter)
e2ae715d KS	91	{
	92	}
	93
595dd3d8 RD	94	static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
	95	{
	96	return -EINVAL;
	97	}
	98
	99	static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
	100	{
	101	return -EINVAL;
	102	}
fb13cb8a KC	103
	104	static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
	105	{
	106	return "Disabled";
	107	}
595dd3d8	108	#endif
456b565c SK	109
456b565c SK	110	#endif /* _LINUX_KMSG_DUMP_H */