Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...

[pandora-kernel.git] / drivers / char / sysrq.c

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 05810c8..1393523 100644 (file)
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -41,7 +41,34 @@
 #include <asm/irq_regs.h>
 
 /* Whether we react on sysrq keys or just ignore them */
-int sysrq_enabled = 1;
+int __read_mostly __sysrq_enabled = 1;
+
+static int __read_mostly sysrq_always_enabled;
+
+int sysrq_on(void)
+{
+       return __sysrq_enabled || sysrq_always_enabled;
+}
+
+/*
+ * A value of 1 means 'all', other nonzero values are an op mask:
+ */
+static inline int sysrq_on_mask(int mask)
+{
+       return sysrq_always_enabled || __sysrq_enabled == 1 ||
+                                               (__sysrq_enabled & mask);
+}
+
+static int __init sysrq_always_enabled_setup(char *str)
+{
+       sysrq_always_enabled = 1;
+       printk(KERN_INFO "debug: sysrq always enabled.\n");
+
+       return 1;
+}
+
+__setup("sysrq_always_enabled", sysrq_always_enabled_setup);
+
 
 static void sysrq_handle_loglevel(int key, struct tty_struct *tty)
 {
@@ -379,8 +406,7 @@ void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
                 * Should we check for enabled operations (/proc/sysrq-trigger
                 * should not) and is the invoked operation enabled?
                 */
-               if (!check_mask || sysrq_enabled == 1 ||
-                   (sysrq_enabled & op_p->enable_mask)) {
+               if (!check_mask || sysrq_on_mask(op_p->enable_mask)) {
                        printk("%s\n", op_p->action_msg);
                        console_loglevel = orig_log_level;
                        op_p->handler(key, tty);
@@ -414,9 +440,8 @@ void __handle_sysrq(int key, struct tty_struct *tty, int check_mask)
  */
 void handle_sysrq(int key, struct tty_struct *tty)
 {
-       if (!sysrq_enabled)
-               return;
-       __handle_sysrq(key, tty, 1);
+       if (sysrq_on())
+               __handle_sysrq(key, tty, 1);
 }
 EXPORT_SYMBOL(handle_sysrq);