1#ifndef _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
 2#define _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_
 3
 4#include <asm/types.h>
 5#include <asm/bitsperlong.h>
 6
 7/**
 8 * __ffs - find first bit in word.
 9 * @word: The word to search
10 *
11 * Undefined if no bit exists, so code should check against 0 first.
12 */
13static __always_inline unsigned long __ffs(unsigned long word)
14{
15	int num = 0;
16
17#if __BITS_PER_LONG == 64
18	if ((word & 0xffffffff) == 0) {
19		num += 32;
20		word >>= 32;
21	}
22#endif
23	if ((word & 0xffff) == 0) {
24		num += 16;
25		word >>= 16;
26	}
27	if ((word & 0xff) == 0) {
28		num += 8;
29		word >>= 8;
30	}
31	if ((word & 0xf) == 0) {
32		num += 4;
33		word >>= 4;
34	}
35	if ((word & 0x3) == 0) {
36		num += 2;
37		word >>= 2;
38	}
39	if ((word & 0x1) == 0)
40		num += 1;
41	return num;
42}
43
44#endif /* _TOOLS_LINUX_ASM_GENERIC_BITOPS___FFS_H_ */