Files
android_kernel_xiaomi_sm8450/include/linux/sysrq.h
Emil Velikov 0f1c9688a1 tty/sysrq: alpha: export and use __sysrq_get_key_op()
Export a pointer to the sysrq_get_key_op(). This way we can cleanly
unregister it, instead of the current solutions of modifuing it inplace.

Since __sysrq_get_key_op() is no longer used externally, let's make it
a static function.

This patch will allow us to limit access to each and every sysrq op and
constify the sysrq handling.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-kernel@vger.kernel.org
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://lore.kernel.org/r/20200513214351.2138580-1-emil.l.velikov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-15 14:53:18 +02:00

84 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* -*- 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 <mj@atrey.karlin.mff.cuni.cz>
*
* (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
* 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>
/* 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);
extern struct sysrq_key_op *__sysrq_reboot_op;
int sysrq_toggle_support(int enable_mask);
int sysrq_mask(void);
#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;
}
static inline int sysrq_mask(void)
{
/* Magic SysRq disabled mask */
return 0;
}
#endif
#endif /* _LINUX_SYSRQ_H */