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#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;
}
/**
* find_next_zero_bit - find the first zero bit in a memory region
* @addr: The address to base the search on
* @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_zero_bit(const unsigned long *addr, int size, int offset);
/**
* __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;
}
/**
* find_next_bit - find the first set bit in a memory region
* @addr: The address to base the search on
* @offset: The bit number to start searching at
* @size: The maximum size to search
*/
int find_next_bit(const unsigned long *addr, int size, int offset);
/**
* 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 */
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