include/linux/sysrq.h

   1 /* -*- linux-c -*-
   2  *
   3  *      $Id: sysrq.h,v 1.3 1997/07/17 11:54:33 mj Exp $
   4  *
   5  *      Linux Magic System Request Key Hacks
   6  *
   7  *      (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   8  *
   9  *      (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
  10  *      overhauled to use key registration
  11  *      based upon discusions in irc://irc.openprojects.net/#kernelnewbies
  12  */
  13
  14 #ifndef _LINUX_SYSRQ_H
  15 #define _LINUX_SYSRQ_H
  16
  17 #include <linux/errno.h>
  18 #include <linux/types.h>
  19
  20 /* Enable/disable SYSRQ support by default (0==no, 1==yes). */
  21 #define SYSRQ_DEFAULT_ENABLE    1
  22
  23 /* Possible values of bitmask for enabling sysrq functions */
  24 /* 0x0001 is reserved for enable everything */
  25 #define SYSRQ_ENABLE_LOG        0x0002
  26 #define SYSRQ_ENABLE_KEYBOARD   0x0004
  27 #define SYSRQ_ENABLE_DUMP       0x0008
  28 #define SYSRQ_ENABLE_SYNC       0x0010
  29 #define SYSRQ_ENABLE_REMOUNT    0x0020
  30 #define SYSRQ_ENABLE_SIGNAL     0x0040
  31 #define SYSRQ_ENABLE_BOOT       0x0080
  32 #define SYSRQ_ENABLE_RTNICE     0x0100
  33
  34 struct sysrq_key_op {
  35         void (*handler)(int);
  36         char *help_msg;
  37         char *action_msg;
  38         int enable_mask;
  39 };
  40
  41 #ifdef CONFIG_MAGIC_SYSRQ
  42
  43 /* Generic SysRq interface -- you may call it from any device driver, supplying
  44  * ASCII code of the key, pointer to registers and kbd/tty structs (if they
  45  * are available -- else NULL's).
  46  */
  47
  48 void handle_sysrq(int key);
  49 void __handle_sysrq(int key, bool check_mask);
  50 int register_sysrq_key(int key, struct sysrq_key_op *op);
  51 int unregister_sysrq_key(int key, struct sysrq_key_op *op);
  52 struct sysrq_key_op *__sysrq_get_key_op(int key);
  53
  54 int sysrq_toggle_support(int enable_mask);
  55
  56 #else
  57
  58 static inline void handle_sysrq(int key)
  59 {
  60 }
  61
  62 static inline void __handle_sysrq(int key, bool check_mask)
  63 {
  64 }
  65
  66 static inline int register_sysrq_key(int key, struct sysrq_key_op *op)
  67 {
  68         return -EINVAL;
  69 }
  70
  71 static inline int unregister_sysrq_key(int key, struct sysrq_key_op *op)
  72 {
  73         return -EINVAL;
  74 }
  75
  76 #endif
  77
  78 #endif /* _LINUX_SYSRQ_H */