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#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/intrinsics.h>
#include <linux/module.h>
#include <linux/bitops.h>
/*
* Find next zero bit in a bitmap reasonably efficiently..
*/
int __find_next_zero_bit (const void *addr, unsigned long size, unsigned long offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (64-offset);
if (size < 64)
goto found_first;
if (~tmp)
goto found_middle;
size -= 64;
result += 64;
}
while (size & ~63UL) {
if (~(tmp = *(p++)))
goto found_middle;
result += 64;
size -= 64;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* any bits zero? */
return result + size; /* nope */
found_middle:
return result + ffz(tmp);
}
EXPORT_SYMBOL(__find_next_zero_bit);
/*
* Find next bit in a bitmap reasonably efficiently..
*/
int __find_next_bit(const void *addr, unsigned long size, unsigned long offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if (offset) {
tmp = *(p++);
tmp &= ~0UL << offset;
if (size < 64)
goto found_first;
if (tmp)
goto found_middle;
size -= 64;
result += 64;
}
while (size & ~63UL) {
if ((tmp = *(p++)))
goto found_middle;
result += 64;
size -= 64;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= ~0UL >> (64-size);
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found_middle:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(__find_next_bit);
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