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 17struct pt_regs; 18struct tty_struct; 19 20/* Possible values of bitmask for enabling sysrq functions */ 21/* 0x0001 is reserved for enable everything */ 22#define SYSRQ_ENABLE_LOG 0x0002 23#define SYSRQ_ENABLE_KEYBOARD 0x0004 24#define SYSRQ_ENABLE_DUMP 0x0008 25#define SYSRQ_ENABLE_SYNC 0x0010 26#define SYSRQ_ENABLE_REMOUNT 0x0020 27#define SYSRQ_ENABLE_SIGNAL 0x0040 28#define SYSRQ_ENABLE_BOOT 0x0080 29#define SYSRQ_ENABLE_RTNICE 0x0100 30 31struct sysrq_key_op { 32 void (*handler)(int, struct tty_struct *); 33 char *help_msg; 34 char *action_msg; 35 int enable_mask; 36}; 37 38#ifdef CONFIG_MAGIC_SYSRQ 39 40extern int sysrq_on(void); 41 42/* 43 * Do not use this one directly: 44 */ 45extern int __sysrq_enabled; 46 47/* Generic SysRq interface -- you may call it from any device driver, supplying 48 * ASCII code of the key, pointer to registers and kbd/tty structs (if they 49 * are available -- else NULL's). 50 */ 51 52void handle_sysrq(int key, struct tty_struct *tty); 53void __handle_sysrq(int key, struct tty_struct *tty, int check_mask); 54int register_sysrq_key(int key, struct sysrq_key_op *op); 55int unregister_sysrq_key(int key, struct sysrq_key_op *op); 56struct sysrq_key_op *__sysrq_get_key_op(int key); 57 58#else 59 60static inline int sysrq_on(void) 61{ 62 return 0; 63} 64static inline int __reterr(void) 65{ 66 return -EINVAL; 67} 68static inline void handle_sysrq(int key, struct tty_struct *tty) 69{ 70} 71 72#define register_sysrq_key(ig,nore) __reterr() 73#define unregister_sysrq_key(ig,nore) __reterr() 74 75#endif 76 77#endif /* _LINUX_SYSRQ_H */ 78