[deliverable/linux.git] / include / asm-x86 / bitops_32.h

#ifndef _I386_BITOPS_H
#define _I386_BITOPS_H

/*
 * Copyright 1992, Linus Torvalds.
 */

/**
 * find_first_zero_bit - find the first zero bit in a memory region
 * @addr: The address to start the search at
 * @size: The maximum size to search
 *
 * Returns the bit number of the first zero bit, not the number of the byte
 * containing a bit.
 */
static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
{
	int d0, d1, d2;
	int res;

	if (!size)
		return 0;
	/* This looks at memory.
	 * Mark it volatile to tell gcc not to move it around
	 */
	asm volatile("movl $-1,%%eax\n\t"
		     "xorl %%edx,%%edx\n\t"
		     "repe; scasl\n\t"
		     "je 1f\n\t"
		     "xorl -4(%%edi),%%eax\n\t"
		     "subl $4,%%edi\n\t"
		     "bsfl %%eax,%%edx\n"
		     "1:\tsubl %%ebx,%%edi\n\t"
		     "shll $3,%%edi\n\t"
		     "addl %%edi,%%edx"
		     : "=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
		     : "1" ((size + 31) >> 5), "2" (addr),
		       "b" (addr) : "memory");
	return res;
}

/**
 * __ffs - find first bit in word.
 * @word: The word to search
 *
 * Undefined if no bit exists, so code should check against 0 first.
 */
static inline unsigned long __ffs(unsigned long word)
{
	__asm__("bsfl %1,%0"
		:"=r" (word)
		:"rm" (word));
	return word;
}

/**
 * find_first_bit - find the first set bit in a memory region
 * @addr: The address to start the search at
 * @size: The maximum size to search
 *
 * Returns the bit number of the first set bit, not the number of the byte
 * containing a bit.
 */
static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
{
	unsigned x = 0;

	while (x < size) {
		unsigned long val = *addr++;
		if (val)
			return __ffs(val) + x;
		x += sizeof(*addr) << 3;
	}
	return x;
}

/**
 * ffz - find first zero in word.
 * @word: The word to search
 *
 * Undefined if no zero exists, so code should check against ~0UL first.
 */
static inline unsigned long ffz(unsigned long word)
{
	__asm__("bsfl %1,%0"
		:"=r" (word)
		:"r" (~word));
	return word;
}

#ifdef __KERNEL__

#include <asm-generic/bitops/sched.h>

/**
 * ffs - find first bit set
 * @x: the word to search
 *
 * This is defined the same way as
 * the libc and compiler builtin ffs routines, therefore
 * differs in spirit from the above ffz() (man ffs).
 */
static inline int ffs(int x)
{
	int r;

	__asm__("bsfl %1,%0\n\t"
		"jnz 1f\n\t"
		"movl $-1,%0\n"
		"1:" : "=r" (r) : "rm" (x));
	return r+1;
}

/**
 * fls - find last bit set
 * @x: the word to search
 *
 * This is defined the same way as ffs().
 */
static inline int fls(int x)
{
	int r;

	__asm__("bsrl %1,%0\n\t"
		"jnz 1f\n\t"
		"movl $-1,%0\n"
		"1:" : "=r" (r) : "rm" (x));
	return r+1;
}

#include <asm-generic/bitops/hweight.h>

#endif /* __KERNEL__ */

#include <asm-generic/bitops/fls64.h>

#ifdef __KERNEL__

#include <asm-generic/bitops/ext2-non-atomic.h>

#define ext2_set_bit_atomic(lock, nr, addr)			\
	test_and_set_bit((nr), (unsigned long *)(addr))
#define ext2_clear_bit_atomic(lock, nr, addr)			\
	test_and_clear_bit((nr), (unsigned long *)(addr))

#include <asm-generic/bitops/minix.h>

#endif /* __KERNEL__ */

#endif /* _I386_BITOPS_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _I386_BITOPS_H
	2	#define _I386_BITOPS_H
	3
	4	/*
	5	* Copyright 1992, Linus Torvalds.
	6	*/
	7
1da177e4 LT	8	/**
	9	* find_first_zero_bit - find the first zero bit in a memory region
	10	* @addr: The address to start the search at
	11	* @size: The maximum size to search
	12	*
ec12fa5c	13	* Returns the bit number of the first zero bit, not the number of the byte
1da177e4 LT	14	* containing a bit.
	15	*/
	16	static inline int find_first_zero_bit(const unsigned long *addr, unsigned size)
	17	{
	18	int d0, d1, d2;
	19	int res;
	20
	21	if (!size)
	22	return 0;
fd591acd JP	23	/* This looks at memory.
	24	* Mark it volatile to tell gcc not to move it around
	25	*/
	26	asm volatile("movl $-1,%%eax\n\t"
	27	"xorl %%edx,%%edx\n\t"
	28	"repe; scasl\n\t"
	29	"je 1f\n\t"
	30	"xorl -4(%%edi),%%eax\n\t"
	31	"subl $4,%%edi\n\t"
	32	"bsfl %%eax,%%edx\n"
	33	"1:\tsubl %%ebx,%%edi\n\t"
	34	"shll $3,%%edi\n\t"
	35	"addl %%edi,%%edx"
	36	: "=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
	37	: "1" ((size + 31) >> 5), "2" (addr),
	38	"b" (addr) : "memory");
1da177e4 LT	39	return res;
	40	}
	41
cd85c8b4 SR	42	/**
	43	* __ffs - find first bit in word.
	44	* @word: The word to search
	45	*
	46	* Undefined if no bit exists, so code should check against 0 first.
	47	*/
	48	static inline unsigned long __ffs(unsigned long word)
	49	{
	50	__asm__("bsfl %1,%0"
	51	:"=r" (word)
	52	:"rm" (word));
	53	return word;
	54	}
	55
1da177e4 LT	56	/**
	57	* find_first_bit - find the first set bit in a memory region
	58	* @addr: The address to start the search at
	59	* @size: The maximum size to search
	60	*
ec12fa5c	61	* Returns the bit number of the first set bit, not the number of the byte
1da177e4 LT	62	* containing a bit.
1da177e4 LT	63	*/
d89c145c	64	static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
1da177e4	65	{
d89c145c	66	unsigned x = 0;
d6d2a2ab LT	67
	68	while (x < size) {
	69	unsigned long val = *addr++;
	70	if (val)
	71	return __ffs(val) + x;
fd591acd	72	x += sizeof(*addr) << 3;
d6d2a2ab	73	}
cd85c8b4	74	return x;
1da177e4 LT	75	}
1da177e4 LT	76
1da177e4 LT	77	/**
	78	* ffz - find first zero in word.
	79	* @word: The word to search
	80	*
	81	* Undefined if no zero exists, so code should check against ~0UL first.
	82	*/
	83	static inline unsigned long ffz(unsigned long word)
	84	{
	85	__asm__("bsfl %1,%0"
	86	:"=r" (word)
	87	:"r" (~word));
	88	return word;
	89	}
	90
1da177e4 LT	91	#ifdef __KERNEL__
1da177e4 LT	92
1cc2b994	93	#include <asm-generic/bitops/sched.h>
1da177e4 LT	94
	95	/**
	96	* ffs - find first bit set
	97	* @x: the word to search
	98	*
	99	* This is defined the same way as
	100	* the libc and compiler builtin ffs routines, therefore
72fd4a35	101	* differs in spirit from the above ffz() (man ffs).
1da177e4 LT	102	*/
	103	static inline int ffs(int x)
	104	{
	105	int r;
	106
	107	__asm__("bsfl %1,%0\n\t"
	108	"jnz 1f\n\t"
	109	"movl $-1,%0\n"
	110	"1:" : "=r" (r) : "rm" (x));
	111	return r+1;
	112	}
	113
d832245d SH	114	/**
	115	* fls - find last bit set
	116	* @x: the word to search
	117	*
72fd4a35	118	* This is defined the same way as ffs().
d832245d SH	119	*/
	120	static inline int fls(int x)
	121	{
	122	int r;
	123
	124	__asm__("bsrl %1,%0\n\t"
	125	"jnz 1f\n\t"
	126	"movl $-1,%0\n"
	127	"1:" : "=r" (r) : "rm" (x));
	128	return r+1;
	129	}
	130
1cc2b994	131	#include <asm-generic/bitops/hweight.h>
1da177e4 LT	132
	133	#endif /* __KERNEL__ */
	134
1cc2b994 AM	135	#include <asm-generic/bitops/fls64.h>
1cc2b994 AM	136
1da177e4 LT	137	#ifdef __KERNEL__
1da177e4 LT	138
1cc2b994 AM	139	#include <asm-generic/bitops/ext2-non-atomic.h>
1cc2b994 AM	140
fd591acd JP	141	#define ext2_set_bit_atomic(lock, nr, addr) \
	142	test_and_set_bit((nr), (unsigned long *)(addr))
	143	#define ext2_clear_bit_atomic(lock, nr, addr) \
	144	test_and_clear_bit((nr), (unsigned long *)(addr))
1cc2b994 AM	145
1cc2b994 AM	146	#include <asm-generic/bitops/minix.h>
1da177e4 LT	147
	148	#endif /* __KERNEL__ */
	149
	150	#endif /* _I386_BITOPS_H */