NTFS_BLOCK_SIZE_BITS
ictx->vcn_size_bits = NTFS_BLOCK_SIZE_BITS;
usa_count = 1 + (logfile_system_page_size >> NTFS_BLOCK_SIZE_BITS);
(vol->mft_record_size >> NTFS_BLOCK_SIZE_BITS) + 1 != le16_to_cpu(m->usa_count) ||
(size >> NTFS_BLOCK_SIZE_BITS) != usa_count)
(size >> NTFS_BLOCK_SIZE_BITS) != usa_count)