vserver 1.9.5.x5

[linux-2.6.git] / drivers / char / sysrq.c

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 2499358..057eaf8 100644 (file)
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -98,6 +98,7 @@ static struct sysrq_key_op sysrq_unraw_op = {
 static void sysrq_handle_reboot(int key, struct pt_regs *pt_regs,
                                struct tty_struct *tty) 
 {
+       local_irq_enable();
        machine_restart(NULL);
 }
 
@@ -216,9 +217,19 @@ static struct sysrq_key_op sysrq_kill_op = {
 
 /* END SIGNAL SYSRQ HANDLERS BLOCK */
 
+static void sysrq_handle_unrt(int key, struct pt_regs *pt_regs,
+                               struct tty_struct *tty)
+{
+       normalize_rt_tasks();
+}
+static struct sysrq_key_op sysrq_unrt_op = {
+       .handler        = sysrq_handle_unrt,
+       .help_msg       = "Nice",
+       .action_msg     = "Nice All RT Tasks"
+};
 
 /* Key Operations table and lock */
-static spinlock_t sysrq_key_table_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(sysrq_key_table_lock);
 #define SYSRQ_KEY_TABLE_LENGTH 36
 static struct sysrq_key_op *sysrq_key_table[SYSRQ_KEY_TABLE_LENGTH] = {
 /* 0 */        &sysrq_loglevel_op,
@@ -250,7 +261,7 @@ static struct sysrq_key_op *sysrq_key_table[SYSRQ_KEY_TABLE_LENGTH] = {
 #endif
 /* l */        NULL,
 /* m */        &sysrq_showmem_op,
-/* n */        NULL,
+/* n */        &sysrq_unrt_op,
 /* o */        NULL, /* This will often be registered
                 as 'Off' at init time */
 /* p */        &sysrq_showregs_op,
@@ -283,14 +294,6 @@ static int sysrq_key_table_key2index(int key) {
        return retval;
 }
 
-/*
- * table lock and unlocking functions, exposed to modules
- */
-
-void __sysrq_lock_table (void) { spin_lock(&sysrq_key_table_lock); }
-
-void __sysrq_unlock_table (void) { spin_unlock(&sysrq_key_table_lock); }
-
 /*
  * get and put functions for the table, exposed to modules.
  */
@@ -312,37 +315,20 @@ void __sysrq_put_key_op (int key, struct sysrq_key_op *op_p) {
                 sysrq_key_table[i] = op_p;
 }
 
-/*
- * This function is called by the keyboard handler when SysRq is pressed
- * and any other keycode arrives.
- */
-
-void handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty)
-{
-       if (!sysrq_enabled)
-               return;
-
-       __sysrq_lock_table();
-       __handle_sysrq_nolock(key, pt_regs, tty);
-       __sysrq_unlock_table();
-}
-
 /*
  * This is the non-locking version of handle_sysrq
  * It must/can only be called by sysrq key handlers,
  * as they are inside of the lock
  */
 
-void __handle_sysrq_nolock(int key, struct pt_regs *pt_regs,
-                          struct tty_struct *tty) 
+void __handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty)
 {
        struct sysrq_key_op *op_p;
        int orig_log_level;
        int i, j;
-       
-       if (!sysrq_enabled)
-               return;
+       unsigned long flags;
 
+       spin_lock_irqsave(&sysrq_key_table_lock, flags);
        orig_log_level = console_loglevel;
        console_loglevel = 7;
        printk(KERN_INFO "SysRq : ");
@@ -364,11 +350,49 @@ void __handle_sysrq_nolock(int key, struct pt_regs *pt_regs,
                printk ("\n");
                console_loglevel = orig_log_level;
        }
+       spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
+}
+
+/*
+ * This function is called by the keyboard handler when SysRq is pressed
+ * and any other keycode arrives.
+ */
+
+void handle_sysrq(int key, struct pt_regs *pt_regs, struct tty_struct *tty)
+{
+       if (!sysrq_enabled)
+               return;
+       __handle_sysrq(key, pt_regs, tty);
+}
+
+int __sysrq_swap_key_ops(int key, struct sysrq_key_op *insert_op_p,
+                                struct sysrq_key_op *remove_op_p) {
+
+       int retval;
+       unsigned long flags;
+
+       spin_lock_irqsave(&sysrq_key_table_lock, flags);
+       if (__sysrq_get_key_op(key) == remove_op_p) {
+               __sysrq_put_key_op(key, insert_op_p);
+               retval = 0;
+       } else {
+               retval = -1;
+       }
+       spin_unlock_irqrestore(&sysrq_key_table_lock, flags);
+
+       return retval;
+}
+
+int register_sysrq_key(int key, struct sysrq_key_op *op_p)
+{
+       return __sysrq_swap_key_ops(key, op_p, NULL);
+}
+
+int unregister_sysrq_key(int key, struct sysrq_key_op *op_p)
+{
+       return __sysrq_swap_key_ops(key, NULL, op_p);
 }
 
 EXPORT_SYMBOL(handle_sysrq);
-EXPORT_SYMBOL(__handle_sysrq_nolock);
-EXPORT_SYMBOL(__sysrq_lock_table);
-EXPORT_SYMBOL(__sysrq_unlock_table);
-EXPORT_SYMBOL(__sysrq_get_key_op);
-EXPORT_SYMBOL(__sysrq_put_key_op);
+EXPORT_SYMBOL(register_sysrq_key);
+EXPORT_SYMBOL(unregister_sysrq_key);