1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* -*- linux-c -*- |
3 | * |
4 | * $Id: sysrq.h,v 1.3 1997/07/17 11:54:33 mj Exp $ |
5 | * |
6 | * Linux Magic System Request Key Hacks |
7 | * |
8 | * (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz> |
9 | * |
10 | * (c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com> |
11 | * overhauled to use key registration |
12 | * based upon discusions in irc://irc.openprojects.net/#kernelnewbies |
13 | */ |
14 | |
15 | #ifndef _LINUX_SYSRQ_H |
16 | #define _LINUX_SYSRQ_H |
17 | |
18 | #include <linux/errno.h> |
19 | #include <linux/types.h> |
20 | |
21 | /* Possible values of bitmask for enabling sysrq functions */ |
22 | /* 0x0001 is reserved for enable everything */ |
23 | #define SYSRQ_ENABLE_LOG 0x0002 |
24 | #define SYSRQ_ENABLE_KEYBOARD 0x0004 |
25 | #define SYSRQ_ENABLE_DUMP 0x0008 |
26 | #define SYSRQ_ENABLE_SYNC 0x0010 |
27 | #define SYSRQ_ENABLE_REMOUNT 0x0020 |
28 | #define SYSRQ_ENABLE_SIGNAL 0x0040 |
29 | #define SYSRQ_ENABLE_BOOT 0x0080 |
30 | #define SYSRQ_ENABLE_RTNICE 0x0100 |
31 | |
32 | struct sysrq_key_op { |
33 | void (* const handler)(u8); |
34 | const char * const help_msg; |
35 | const char * const action_msg; |
36 | const int enable_mask; |
37 | }; |
38 | |
39 | #ifdef CONFIG_MAGIC_SYSRQ |
40 | |
41 | /* Generic SysRq interface -- you may call it from any device driver, supplying |
42 | * ASCII code of the key, pointer to registers and kbd/tty structs (if they |
43 | * are available -- else NULL's). |
44 | */ |
45 | |
46 | void handle_sysrq(u8 key); |
47 | void __handle_sysrq(u8 key, bool check_mask); |
48 | int register_sysrq_key(u8 key, const struct sysrq_key_op *op); |
49 | int unregister_sysrq_key(u8 key, const struct sysrq_key_op *op); |
50 | extern const struct sysrq_key_op *__sysrq_reboot_op; |
51 | |
52 | int sysrq_toggle_support(int enable_mask); |
53 | int sysrq_mask(void); |
54 | |
55 | #else |
56 | |
57 | static inline void handle_sysrq(u8 key) |
58 | { |
59 | } |
60 | |
61 | static inline void __handle_sysrq(u8 key, bool check_mask) |
62 | { |
63 | } |
64 | |
65 | static inline int register_sysrq_key(u8 key, const struct sysrq_key_op *op) |
66 | { |
67 | return -EINVAL; |
68 | } |
69 | |
70 | static inline int unregister_sysrq_key(u8 key, const struct sysrq_key_op *op) |
71 | { |
72 | return -EINVAL; |
73 | } |
74 | |
75 | static inline int sysrq_mask(void) |
76 | { |
77 | /* Magic SysRq disabled mask */ |
78 | return 0; |
79 | } |
80 | |
81 | #endif |
82 | |
83 | #endif /* _LINUX_SYSRQ_H */ |
84 | |