}
#ifndef zero_bytemask
-#ifdef CONFIG_64BIT
-#define zero_bytemask(mask) (~0ul << fls64(mask))
-#else
-#define zero_bytemask(mask) (~0ul << fls(mask))
-#endif /* CONFIG_64BIT */
-#endif /* zero_bytemask */
+#define zero_bytemask(mask) (~1ul << __fls(mask))
+#endif
#endif /* _ASM_WORD_AT_A_TIME_H */