#include /** * 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); }