xref: /linux-6.15/include/linux/sysrq.h (revision 4bedea94)
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 <[email protected]>
8  *
9  *	(c) 2000 Crutcher Dunnavant <[email protected]>
10  *	overhauled to use key registration
11  *	based upon discusions in irc://irc.openprojects.net/#kernelnewbies
12  */
13 
14 #include <linux/config.h>
15 
16 struct pt_regs;
17 struct tty_struct;
18 
19 /* Possible values of bitmask for enabling sysrq functions */
20 /* 0x0001 is reserved for enable everything */
21 #define SYSRQ_ENABLE_LOG	0x0002
22 #define SYSRQ_ENABLE_KEYBOARD	0x0004
23 #define SYSRQ_ENABLE_DUMP	0x0008
24 #define SYSRQ_ENABLE_SYNC	0x0010
25 #define SYSRQ_ENABLE_REMOUNT	0x0020
26 #define SYSRQ_ENABLE_SIGNAL	0x0040
27 #define SYSRQ_ENABLE_BOOT	0x0080
28 #define SYSRQ_ENABLE_RTNICE	0x0100
29 
30 struct sysrq_key_op {
31 	void (*handler)(int, struct pt_regs *, struct tty_struct *);
32 	char *help_msg;
33 	char *action_msg;
34 	int enable_mask;
35 };
36 
37 #ifdef CONFIG_MAGIC_SYSRQ
38 
39 /* Generic SysRq interface -- you may call it from any device driver, supplying
40  * ASCII code of the key, pointer to registers and kbd/tty structs (if they
41  * are available -- else NULL's).
42  */
43 
44 void handle_sysrq(int, struct pt_regs *, struct tty_struct *);
45 void __handle_sysrq(int, struct pt_regs *, struct tty_struct *, int check_mask);
46 int register_sysrq_key(int, struct sysrq_key_op *);
47 int unregister_sysrq_key(int, struct sysrq_key_op *);
48 struct sysrq_key_op *__sysrq_get_key_op(int key);
49 
50 #else
51 
52 static inline int __reterr(void)
53 {
54 	return -EINVAL;
55 }
56 
57 #define register_sysrq_key(ig,nore) __reterr()
58 #define unregister_sysrq_key(ig,nore) __reterr()
59 
60 #endif
61