vt,console,kdb: implement atomic console enter/leave functions
These functions allow the kernel debugger to save and restore the
state of the system console.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
CC: David Airlie <airlied@linux.ie>
CC: Andrew Morton <akpm@linux-foundation.org>
diff --git a/include/linux/console.h b/include/linux/console.h
index dcca533..f76fc29 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -55,6 +55,16 @@
void (*con_invert_region)(struct vc_data *, u16 *, int);
u16 *(*con_screen_pos)(struct vc_data *, int);
unsigned long (*con_getxy)(struct vc_data *, unsigned long, int *, int *);
+ /*
+ * Prepare the console for the debugger. This includes, but is not
+ * limited to, unblanking the console, loading an appropriate
+ * palette, and allowing debugger generated output.
+ */
+ int (*con_debug_enter)(struct vc_data *);
+ /*
+ * Restore the console to its pre-debug state as closely as possible.
+ */
+ int (*con_debug_leave)(struct vc_data *);
};
extern const struct consw *conswitchp;
@@ -69,6 +79,9 @@
int unregister_con_driver(const struct consw *csw);
int take_over_console(const struct consw *sw, int first, int last, int deflt);
void give_up_console(const struct consw *sw);
+int con_debug_enter(struct vc_data *vc);
+int con_debug_leave(void);
+
/* scroll */
#define SM_UP (1)
#define SM_DOWN (2)