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 19struct pt_regs; 20struct tty_struct; 21 22/* Possible values of bitmask for enabling sysrq functions */ 23/* 0x0001 is reserved for enable everything */ 24#define SYSRQ_ENABLE_LOG 0x0002 25#define SYSRQ_ENABLE_KEYBOARD 0x0004 26#define SYSRQ_ENABLE_DUMP 0x0008 27#define SYSRQ_ENABLE_SYNC 0x0010 28#define SYSRQ_ENABLE_REMOUNT 0x0020 29#define SYSRQ_ENABLE_SIGNAL 0x0040 30#define SYSRQ_ENABLE_BOOT 0x0080 31#define SYSRQ_ENABLE_RTNICE 0x0100 32 33struct sysrq_key_op { 34 void (*handler)(int, struct tty_struct *); 35 char *help_msg; 36 char *action_msg; 37 int enable_mask; 38}; 39 40#ifdef CONFIG_MAGIC_SYSRQ 41 42extern int sysrq_on(void); 43 44/* 45 * Do not use this one directly: 46 */ 47extern int __sysrq_enabled; 48 49/* Generic SysRq interface -- you may call it from any device driver, supplying 50 * ASCII code of the key, pointer to registers and kbd/tty structs (if they 51 * are available -- else NULL's). 52 */ 53 54void handle_sysrq(int key, struct tty_struct *tty); 55void __handle_sysrq(int key, struct tty_struct *tty, int check_mask); 56int register_sysrq_key(int key, struct sysrq_key_op *op); 57int unregister_sysrq_key(int key, struct sysrq_key_op *op); 58struct sysrq_key_op *__sysrq_get_key_op(int key); 59 60#else 61 62static inline int sysrq_on(void) 63{ 64 return 0; 65} 66static inline int __reterr(void) 67{ 68 return -EINVAL; 69} 70static inline void handle_sysrq(int key, struct tty_struct *tty) 71{ 72} 73 74#define register_sysrq_key(ig,nore) __reterr() 75#define unregister_sysrq_key(ig,nore) __reterr() 76 77#endif 78 79#endif /* _LINUX_SYSRQ_H */ 80