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
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
kmsg_dump_desc(enum kmsg_dump_reason reason,const char * desc)85 static inline void kmsg_dump_desc(enum kmsg_dump_reason reason, const char *desc)
86 {
87 }
88
kmsg_dump_get_line(struct kmsg_dump_iter * iter,bool syslog,const char * line,size_t size,size_t * len)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
kmsg_dump_get_buffer(struct kmsg_dump_iter * iter,bool syslog,char * buf,size_t size,size_t * len)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
kmsg_dump_rewind(struct kmsg_dump_iter * iter)101 static inline void kmsg_dump_rewind(struct kmsg_dump_iter *iter)
102 {
103 }
104
kmsg_dump_register(struct kmsg_dumper * dumper)105 static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
106 {
107 return -EINVAL;
108 }
109
kmsg_dump_unregister(struct kmsg_dumper * dumper)110 static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
111 {
112 return -EINVAL;
113 }
114
kmsg_dump_reason_str(enum kmsg_dump_reason reason)115 static inline const char *kmsg_dump_reason_str(enum kmsg_dump_reason reason)
116 {
117 return "Disabled";
118 }
119 #endif
120
kmsg_dump(enum kmsg_dump_reason reason)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 */
127