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#include <linux/bitops.h>
#include <linux/module.h>
/**
* find_next_bit - find the first set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
int find_next_bit(const unsigned long *addr, int size, int offset)
{
const unsigned long *p = addr + (offset >> 5);
int set = 0, bit = offset & 31, res;
if (bit) {
/*
* Look for nonzero in the first 32 bits:
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (*p >> bit));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No set bit yet, search remaining full words for a bit
*/
res = find_first_bit (p, size - 32 * (p - addr));
return (offset + set + res);
}
EXPORT_SYMBOL(find_next_bit);
/**
* find_next_zero_bit - find the first zero bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
int find_next_zero_bit(const unsigned long *addr, int size, int offset)
{
unsigned long * p = ((unsigned long *) addr) + (offset >> 5);
int set = 0, bit = offset & 31, res;
if (bit) {
/*
* Look for zero in the first 32 bits.
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (~(*p >> bit)));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No zero yet, search remaining full bytes for a zero
*/
res = find_first_zero_bit (p, size - 32 * (p - (unsigned long *) addr));
return (offset + set + res);
}
EXPORT_SYMBOL(find_next_zero_bit);
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