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#include <linux/bitops.h>
/**
* find_next_bit - find the next 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
*/
unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned long *p = 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);
}
/* find_next_zero_bit() finds the first zero bit in a bit string of length
* 'size' bits, starting the search at bit 'offset'. This is largely based
* on Linus's ALPHA routines, which are pretty portable BTW.
*/
unsigned long find_next_zero_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
const unsigned long *p = 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) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
unsigned long find_next_zero_le_bit(unsigned long *addr, unsigned long size, unsigned long offset)
{
unsigned long *p = addr + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if(offset) {
tmp = __swab64p(p++);
tmp |= (~0UL >> (64-offset));
if(size < 64)
goto found_first;
if(~tmp)
goto found_middle;
size -= 64;
result += 64;
}
while(size & ~63) {
if(~(tmp = __swab64p(p++)))
goto found_middle;
result += 64;
size -= 64;
}
if(!size)
return result;
tmp = __swab64p(p);
found_first:
tmp |= (~0UL << size);
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
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