sysrq.h

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/* -*- linux-c -*-
 *
 *  $Id: sysrq.h,v 1.3 1997/07/17 11:54:33 mj Exp $
 *
 *  Linux Magic System Request Key Hacks
 *
 *  (c) 1997 Martin Mares <[email protected]>
 *
 *  (c) 2000 Crutcher Dunnavant <[email protected]>
 *  overhauled to use key registration
 *  based upon discusions in irc://irc.openprojects.net/#kernelnewbies
 */

#ifndef _LINUX_SYSRQ_H
#define _LINUX_SYSRQ_H

#include <linux/errno.h>
#include <linux/types.h>

/* Enable/disable SYSRQ support by default (0==no, 1==yes). */
#define SYSRQ_DEFAULT_ENABLE    1

/* Possible values of bitmask for enabling sysrq functions */
/* 0x0001 is reserved for enable everything */
#define SYSRQ_ENABLE_LOG    0x0002
#define SYSRQ_ENABLE_KEYBOARD   0x0004
#define SYSRQ_ENABLE_DUMP   0x0008
#define SYSRQ_ENABLE_SYNC   0x0010
#define SYSRQ_ENABLE_REMOUNT    0x0020
#define SYSRQ_ENABLE_SIGNAL 0x0040
#define SYSRQ_ENABLE_BOOT   0x0080
#define SYSRQ_ENABLE_RTNICE 0x0100

struct sysrq_key_op {
    void (*handler)(int);
    char *help_msg;
    char *action_msg;
    int enable_mask;
};

#ifdef CONFIG_MAGIC_SYSRQ

/* Generic SysRq interface -- you may call it from any device driver, supplying
 * ASCII code of the key, pointer to registers and kbd/tty structs (if they
 * are available -- else NULL's).
 */

void handle_sysrq(int key);
void __handle_sysrq(int key, bool check_mask);
int register_sysrq_key(int key, struct sysrq_key_op *op);
int unregister_sysrq_key(int key, struct sysrq_key_op *op);
struct sysrq_key_op *__sysrq_get_key_op(int key);

int sysrq_toggle_support(int enable_mask);

#else

static inline void handle_sysrq(int key)
{
}

static inline void __handle_sysrq(int key, bool check_mask)
{
}

static inline int register_sysrq_key(int key, struct sysrq_key_op *op)
{
    return -EINVAL;
}

static inline int unregister_sysrq_key(int key, struct sysrq_key_op *op)
{
    return -EINVAL;
}

#endif

#endif /* _LINUX_SYSRQ_H */