Index: linux-2.6.11-rc4-ck1/include/linux/ioprio.h
===================================================================
--- linux-2.6.11-rc4-ck1.orig/include/linux/ioprio.h	2005-02-13 15:58:15.000000000 +1100
+++ linux-2.6.11-rc4-ck1/include/linux/ioprio.h	2005-02-13 15:58:56.000000000 +1100
@@ -49,7 +49,13 @@ static inline int task_ioprio(struct tas
 
 static inline int task_nice_ioprio(struct task_struct *task)
 {
-	return (task_nice(task) + 20) / 5;
+	int effective_nice = task_nice(task);
+
+	if (batch_task(task))
+		effective_nice = 19;
+	else if (iso_task(task))
+		effective_nice = -20;
+	return (effective_nice + 20) / 5;
 }
 
 /*