[PATCH] debug: add sysrq_always_enabled boot option
Most distributions enable sysrq support but set it to 0 by default. Add a
sysrq_always_enabled boot option to always-enable sysrq keys. Useful for
debugging - without having to modify the disribution's config files (which
might not be possible if the kernel is on a live CD, etc.).
Also, while at it, clean up the sysrq interfaces.
[bunk@stusta.de: make sysrq_always_enabled_setup() static]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/sysrq.h b/include/linux/sysrq.h
index 9df8833..98a1d8c 100644
--- a/include/linux/sysrq.h
+++ b/include/linux/sysrq.h
@@ -37,23 +37,37 @@
#ifdef CONFIG_MAGIC_SYSRQ
+extern int sysrq_on(void);
+
+/*
+ * Do not use this one directly:
+ */
+extern int __sysrq_enabled;
+
/* 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, struct tty_struct *);
-void __handle_sysrq(int, struct tty_struct *, int check_mask);
-int register_sysrq_key(int, struct sysrq_key_op *);
-int unregister_sysrq_key(int, struct sysrq_key_op *);
+void handle_sysrq(int key, struct tty_struct *tty);
+void __handle_sysrq(int key, struct tty_struct *tty, int check_mask);
+int register_sysrq_key(int key, struct sysrq_key_op *op);
+int unregister_sysrq_key(int key, struct sysrq_key_op *op);
struct sysrq_key_op *__sysrq_get_key_op(int key);
#else
+static inline int sysrq_on(void)
+{
+ return 0;
+}
static inline int __reterr(void)
{
return -EINVAL;
}
+static inline void handle_sysrq(int key, struct tty_struct *tty)
+{
+}
#define register_sysrq_key(ig,nore) __reterr()
#define unregister_sysrq_key(ig,nore) __reterr()