linux - include/linux/kmsg

126 lines · 3.1 KiB

1	/*
2	* linux/include/kmsg_dump.h
3	*
4	* Copyright (C) 2009 Net Insight AB
5	*
6	* Author: Simon Kagstrom <[email protected]>
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
15	#include <linux/errno.h>
16	#include <linux/list.h>
17
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	*/
23	enum kmsg_dump_reason {
24	KMSG_DUMP_UNDEF,
25	KMSG_DUMP_PANIC,
26	KMSG_DUMP_OOPS,
27	KMSG_DUMP_EMERG,
28	KMSG_DUMP_SHUTDOWN,
29	KMSG_DUMP_MAX
30	};
31
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
42	/**
43	* struct kmsg_dump_detail - kernel crash detail
44	* @reason: reason for the crash, see kmsg_dump_reason.
45	* @description: optional short string, to provide additional information.
46	*/
47
48	struct kmsg_dump_detail {
49	enum kmsg_dump_reason reason;
50	const char *description;
51	};
52
53	/**
54	* struct kmsg_dumper - kernel crash message dumper structure
55	* @list: Entry in the dumper list (private)
56	* @dump: Call into dumping code which will retrieve the data with
57	* through the record iterator
58	* @max_reason: filter for highest reason number that should be dumped
59	* @registered: Flag that specifies if this is already registered
60	*/
61	struct kmsg_dumper {
62	struct list_head list;
63	void (dump)(struct kmsg_dumper dumper, struct kmsg_dump_detail *detail);
64	enum kmsg_dump_reason max_reason;
65	bool registered;
66	};
67
68	#ifdef CONFIG_PRINTK
69	void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc);
70
71	bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
72	char line, size_t size, size_t len);
73
74	bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
75	char buf, size_t size, size_t len_out);
76
77	void kmsg_dump_rewind(struct kmsg_dump_iter *iter);
78
79	int kmsg_dump_register(struct kmsg_dumper *dumper);
80
81	int kmsg_dump_unregister(struct kmsg_dumper *dumper);
82
83	const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason);
84	#else
85	static inline void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
86	{
87	}
88
89	static inline bool kmsg_dump_get_line(struct kmsg_dump_iter *iter, bool syslog,
90	const char line, size_t size, size_t len)
91	{
92	return false;
93	}
94
95	static inline bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog,
96	char buf, size_t size, size_t len)
97	{
98	return false;
99	}
100
101	static inline void kmsg_dump_rewind(struct kmsg_dump_iter *iter)
102	{
103	}
104
105	static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
106	{
107	return -EINVAL;
108	}
109
110	static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
111	{
112	return -EINVAL;
113	}
114
115	static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
116	{
117	return "Disabled";
118	}
119	#endif
120
121	static inline void kmsg_dump(enum kmsg_dump_reason reason)
122	{
123	kmsg_dump_desc(reason, NULL);
124	}
125
126	#endif /* _LINUX_KMSG_DUMP_H */