sysrq.h (2002B)
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 15#ifndef _LINUX_SYSRQ_H 16#define _LINUX_SYSRQ_H 17 18#include <linux/errno.h> 19#include <linux/types.h> 20 21/* Possible values of bitmask for enabling sysrq functions */ 22/* 0x0001 is reserved for enable everything */ 23#define SYSRQ_ENABLE_LOG 0x0002 24#define SYSRQ_ENABLE_KEYBOARD 0x0004 25#define SYSRQ_ENABLE_DUMP 0x0008 26#define SYSRQ_ENABLE_SYNC 0x0010 27#define SYSRQ_ENABLE_REMOUNT 0x0020 28#define SYSRQ_ENABLE_SIGNAL 0x0040 29#define SYSRQ_ENABLE_BOOT 0x0080 30#define SYSRQ_ENABLE_RTNICE 0x0100 31 32struct sysrq_key_op { 33 void (* const handler)(int); 34 const char * const help_msg; 35 const char * const action_msg; 36 const int enable_mask; 37}; 38 39#ifdef CONFIG_MAGIC_SYSRQ 40 41/* Generic SysRq interface -- you may call it from any device driver, supplying 42 * ASCII code of the key, pointer to registers and kbd/tty structs (if they 43 * are available -- else NULL's). 44 */ 45 46void handle_sysrq(int key); 47void __handle_sysrq(int key, bool check_mask); 48int register_sysrq_key(int key, const struct sysrq_key_op *op); 49int unregister_sysrq_key(int key, const struct sysrq_key_op *op); 50extern const struct sysrq_key_op *__sysrq_reboot_op; 51 52int sysrq_toggle_support(int enable_mask); 53int sysrq_mask(void); 54 55#else 56 57static inline void handle_sysrq(int key) 58{ 59} 60 61static inline void __handle_sysrq(int key, bool check_mask) 62{ 63} 64 65static inline int register_sysrq_key(int key, const struct sysrq_key_op *op) 66{ 67 return -EINVAL; 68} 69 70static inline int unregister_sysrq_key(int key, const struct sysrq_key_op *op) 71{ 72 return -EINVAL; 73} 74 75static inline int sysrq_mask(void) 76{ 77 /* Magic SysRq disabled mask */ 78 return 0; 79} 80 81#endif 82 83#endif /* _LINUX_SYSRQ_H */