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#include <linux/types.h>
19
20/* Enable/disable SYSRQ support by default (0==no, 1==yes). */
21#define SYSRQ_DEFAULT_ENABLE	1
22
23/* Possible values of bitmask for enabling sysrq functions */
24/* 0x0001 is reserved for enable everything */
25#define SYSRQ_ENABLE_LOG	0x0002
26#define SYSRQ_ENABLE_KEYBOARD	0x0004
27#define SYSRQ_ENABLE_DUMP	0x0008
28#define SYSRQ_ENABLE_SYNC	0x0010
29#define SYSRQ_ENABLE_REMOUNT	0x0020
30#define SYSRQ_ENABLE_SIGNAL	0x0040
31#define SYSRQ_ENABLE_BOOT	0x0080
32#define SYSRQ_ENABLE_RTNICE	0x0100
33
34struct sysrq_key_op {
35	void (*handler)(int);
36	char *help_msg;
37	char *action_msg;
38	int enable_mask;
39};
40
41#ifdef CONFIG_MAGIC_SYSRQ
42
43/* Generic SysRq interface -- you may call it from any device driver, supplying
44 * ASCII code of the key, pointer to registers and kbd/tty structs (if they
45 * are available -- else NULL's).
46 */
47
48void handle_sysrq(int key);
49void __handle_sysrq(int key, bool check_mask);
50int register_sysrq_key(int key, struct sysrq_key_op *op);
51int unregister_sysrq_key(int key, struct sysrq_key_op *op);
52struct sysrq_key_op *__sysrq_get_key_op(int key);
53
54int sysrq_toggle_support(int enable_mask);
55
56#else
57
58static inline void handle_sysrq(int key)
59{
60}
61
62static inline void __handle_sysrq(int key, bool check_mask)
63{
64}
65
66static inline int register_sysrq_key(int key, struct sysrq_key_op *op)
67{
68	return -EINVAL;
69}
70
71static inline int unregister_sysrq_key(int key, struct sysrq_key_op *op)
72{
73	return -EINVAL;
74}
75
76#endif
77
78#endif /* _LINUX_SYSRQ_H */
79