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 struct pt_regs;
18 struct tty_struct;
19
20 /* Possible values of bitmask for enabling sysrq functions */
21 /* 0x0001 is reserved for enable everything */
22 #define SYSRQ_ENABLE_LOG 0x0002
23 #define SYSRQ_ENABLE_KEYBOARD 0x0004
24 #define SYSRQ_ENABLE_DUMP 0x0008
25 #define SYSRQ_ENABLE_SYNC 0x0010
26 #define SYSRQ_ENABLE_REMOUNT 0x0020
27 #define SYSRQ_ENABLE_SIGNAL 0x0040
28 #define SYSRQ_ENABLE_BOOT 0x0080
29 #define SYSRQ_ENABLE_RTNICE 0x0100
30
31 struct sysrq_key_op {
32 void (*handler)(int, struct tty_struct *);
33 char *help_msg;
34 char *action_msg;
35 int enable_mask;
36 };
37
38 #ifdef CONFIG_MAGIC_SYSRQ
39
40 extern int sysrq_on(void);
41
42 /*
43 * Do not use this one directly:
44 */
45 extern int __sysrq_enabled;
46
47 /* Generic SysRq interface -- you may call it from any device driver, supplying
48 * ASCII code of the key, pointer to registers and kbd/tty structs (if they
49 * are available -- else NULL's).
50 */
51
52 void handle_sysrq(int key, struct tty_struct *tty);
53 void __handle_sysrq(int key, struct tty_struct *tty, int check_mask);
54 int register_sysrq_key(int key, struct sysrq_key_op *op);
55 int unregister_sysrq_key(int key, struct sysrq_key_op *op);
56 struct sysrq_key_op *__sysrq_get_key_op(int key);
57
58 #else
59
sysrq_on(void)60 static inline int sysrq_on(void)
61 {
62 return 0;
63 }
__reterr(void)64 static inline int __reterr(void)
65 {
66 return -EINVAL;
67 }
handle_sysrq(int key,struct tty_struct * tty)68 static inline void handle_sysrq(int key, struct tty_struct *tty)
69 {
70 }
71
72 #define register_sysrq_key(ig,nore) __reterr()
73 #define unregister_sysrq_key(ig,nore) __reterr()
74
75 #endif
76
77 #endif /* _LINUX_SYSRQ_H */
78