[PATCH] bitops: generic ffz()

This patch introduces the C-language equivalent of the function: unsigned long
ffz(unsigned long word);

In include/asm-generic/bitops/ffz.h

This code largely copied from: include/asm-parisc/bitops.h

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/include/asm-generic/bitops/ffz.h b/include/asm-generic/bitops/ffz.h
new file mode 100644 (file)
index 0000000..6744bd4
--- /dev/null
+++ b/include/asm-generic/bitops/ffz.h
@@ -0,0 +1,12 @@
+#ifndef _ASM_GENERIC_BITOPS_FFZ_H_
+#define _ASM_GENERIC_BITOPS_FFZ_H_
+
+/*
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+#define ffz(x)  __ffs(~(x))
+
+#endif /* _ASM_GENERIC_BITOPS_FFZ_H_ */