diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index dcafe0b..907dd58 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -145,6 +145,7 @@
 extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
 extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
 
+#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG))
 #define BITMAP_LAST_WORD_MASK(nbits)					\
 (									\
 	((nbits) % BITS_PER_LONG) ?					\