diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
index 8eec0ec..8c96897 100644
--- a/arch/x86/kernel/ioport.c
+++ b/arch/x86/kernel/ioport.c
@@ -14,22 +14,9 @@
 #include <linux/slab.h>
 #include <linux/thread_info.h>
 #include <linux/syscalls.h>
+#include <linux/bitmap.h>
 #include <asm/syscalls.h>
 
-/* Set EXTENT bits starting at BASE in BITMAP to value TURN_ON. */
-static void set_bitmap(unsigned long *bitmap, unsigned int base,
-		       unsigned int extent, int new_value)
-{
-	unsigned int i;
-
-	for (i = base; i < base + extent; i++) {
-		if (new_value)
-			__set_bit(i, bitmap);
-		else
-			__clear_bit(i, bitmap);
-	}
-}
-
 /*
  * this changes the io permissions bitmap in the current task.
  */
@@ -69,7 +56,10 @@
 	 */
 	tss = &per_cpu(init_tss, get_cpu());
 
-	set_bitmap(t->io_bitmap_ptr, from, num, !turn_on);
+	if (turn_on)
+		bitmap_clear(t->io_bitmap_ptr, from, num);
+	else
+		bitmap_set(t->io_bitmap_ptr, from, num);
 
 	/*
 	 * Search for a (possibly new) maximum. This is simple and stupid,