LXR linux/include/linux/kmsg

   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 */
  23enum kmsg_dump_reason {
  24        KMSG_DUMP_UNDEF,
  25        KMSG_DUMP_PANIC,
  26        KMSG_DUMP_OOPS,
  27        KMSG_DUMP_EMERG,
  28        KMSG_DUMP_RESTART,
  29        KMSG_DUMP_HALT,
  30        KMSG_DUMP_POWEROFF,
  31};
  32
  33/**
  34 * struct kmsg_dumper - kernel crash message dumper structure
  35 * @list:       Entry in the dumper list (private)
  36 * @dump:       Call into dumping code which will retrieve the data with
  37 *              through the record iterator
  38 * @max_reason: filter for highest reason number that should be dumped
  39 * @registered: Flag that specifies if this is already registered
  40 */
  41struct kmsg_dumper {
  42        struct list_head list;
  43        void (*dump)(struct kmsg_dumper *dumper, enum kmsg_dump_reason reason);
  44        enum kmsg_dump_reason max_reason;
  45        bool active;
  46        bool registered;
  47
  48        /* private state of the kmsg iterator */
  49        u32 cur_idx;
  50        u32 next_idx;
  51        u64 cur_seq;
  52        u64 next_seq;
  53};
  54
  55#ifdef CONFIG_PRINTK
  56void kmsg_dump(enum kmsg_dump_reason reason);
  57
  58bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper, bool syslog,
  59                               char *line, size_t size, size_t *len);
  60
  61bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
  62                        char *line, size_t size, size_t *len);
  63
  64bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
  65                          char *buf, size_t size, size_t *len);
  66
  67void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper);
  68
  69void kmsg_dump_rewind(struct kmsg_dumper *dumper);
  70
  71int kmsg_dump_register(struct kmsg_dumper *dumper);
  72
  73int kmsg_dump_unregister(struct kmsg_dumper *dumper);
  74#else
  75static inline void kmsg_dump(enum kmsg_dump_reason reason)
  76{
  77}
  78
  79static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper *dumper,
  80                                             bool syslog, const char *line,
  81                                             size_t size, size_t *len)
  82{
  83        return false;
  84}
  85
  86static inline bool kmsg_dump_get_line(struct kmsg_dumper *dumper, bool syslog,
  87                                const char *line, size_t size, size_t *len)
  88{
  89        return false;
  90}
  91
  92static inline bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog,
  93                                        char *buf, size_t size, size_t *len)
  94{
  95        return false;
  96}
  97
  98static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper *dumper)
  99{
 100}
 101
 102static inline void kmsg_dump_rewind(struct kmsg_dumper *dumper)
 103{
 104}
 105
 106static inline int kmsg_dump_register(struct kmsg_dumper *dumper)
 107{
 108        return -EINVAL;
 109}
 110
 111static inline int kmsg_dump_unregister(struct kmsg_dumper *dumper)
 112{
 113        return -EINVAL;
 114}
 115#endif
 116
 117#endif /* _LINUX_KMSG_DUMP_H */
 118