BITMAP_GRANULARITY
BITMAP_GRANULARITY - 1) / BITMAP_GRANULARITY;
#if BITMAP_GRANULARITY < PAGE_SIZE
__set_bit(((char *)ptr - (char *)wc->memory_map) / BITMAP_GRANULARITY,
region.sector = (sector_t)i * (BITMAP_GRANULARITY >> SECTOR_SHIFT);
region.count = (sector_t)(j - i) * (BITMAP_GRANULARITY >> SECTOR_SHIFT);
req.mem.ptr.vma = (char *)wc->memory_map + (size_t)i * BITMAP_GRANULARITY;