sysrq.h 2.0 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283
  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /* -*- linux-c -*-
  3. *
  4. * $Id: sysrq.h,v 1.3 1997/07/17 11:54:33 mj Exp $
  5. *
  6. * Linux Magic System Request Key Hacks
  7. *
  8. * (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
  9. *
  10. * (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
  11. * overhauled to use key registration
  12. * based upon discusions in irc://irc.openprojects.net/#kernelnewbies
  13. */
  14. #ifndef _LINUX_SYSRQ_H
  15. #define _LINUX_SYSRQ_H
  16. #include <linux/errno.h>
  17. #include <linux/types.h>
  18. /* Possible values of bitmask for enabling sysrq functions */
  19. /* 0x0001 is reserved for enable everything */
  20. #define SYSRQ_ENABLE_LOG 0x0002
  21. #define SYSRQ_ENABLE_KEYBOARD 0x0004
  22. #define SYSRQ_ENABLE_DUMP 0x0008
  23. #define SYSRQ_ENABLE_SYNC 0x0010
  24. #define SYSRQ_ENABLE_REMOUNT 0x0020
  25. #define SYSRQ_ENABLE_SIGNAL 0x0040
  26. #define SYSRQ_ENABLE_BOOT 0x0080
  27. #define SYSRQ_ENABLE_RTNICE 0x0100
  28. struct sysrq_key_op {
  29. void (* const handler)(int);
  30. const char * const help_msg;
  31. const char * const action_msg;
  32. const int enable_mask;
  33. };
  34. #ifdef CONFIG_MAGIC_SYSRQ
  35. /* Generic SysRq interface -- you may call it from any device driver, supplying
  36. * ASCII code of the key, pointer to registers and kbd/tty structs (if they
  37. * are available -- else NULL's).
  38. */
  39. void handle_sysrq(int key);
  40. void __handle_sysrq(int key, bool check_mask);
  41. int register_sysrq_key(int key, const struct sysrq_key_op *op);
  42. int unregister_sysrq_key(int key, const struct sysrq_key_op *op);
  43. extern const struct sysrq_key_op *__sysrq_reboot_op;
  44. int sysrq_toggle_support(int enable_mask);
  45. int sysrq_mask(void);
  46. #else
  47. static inline void handle_sysrq(int key)
  48. {
  49. }
  50. static inline void __handle_sysrq(int key, bool check_mask)
  51. {
  52. }
  53. static inline int register_sysrq_key(int key, const struct sysrq_key_op *op)
  54. {
  55. return -EINVAL;
  56. }
  57. static inline int unregister_sysrq_key(int key, const struct sysrq_key_op *op)
  58. {
  59. return -EINVAL;
  60. }
  61. static inline int sysrq_mask(void)
  62. {
  63. /* Magic SysRq disabled mask */
  64. return 0;
  65. }
  66. #endif
  67. #endif /* _LINUX_SYSRQ_H */