void ntfs_attr_init(ntfs_attr *na, const BOOL non_resident,
		const ATTR_FLAGS data_flags,
		const BOOL encrypted, const BOOL sparse,
		const s64 allocated_size, const s64 data_size,
		const s64 initialized_size, const s64 compressed_size,
		const u8 compression_unit)
{
	if (!NAttrInitialized(na)) {
		na->data_flags = data_flags;
		if (non_resident)
			NAttrSetNonResident(na);
		if (data_flags & ATTR_COMPRESSION_MASK)
			NAttrSetCompressed(na);
		if (encrypted)
			NAttrSetEncrypted(na);
		if (sparse)
			NAttrSetSparse(na);
		na->allocated_size = allocated_size;
		na->data_size = data_size;
		na->initialized_size = initialized_size;
		if ((data_flags & ATTR_COMPRESSION_MASK) || sparse) {
			ntfs_volume *vol = na->ni->vol;

			na->compressed_size = compressed_size;
			na->compression_block_clusters = 1 << compression_unit;
			na->compression_block_size = 1 << (compression_unit +
					vol->cluster_size_bits);
			na->compression_block_size_bits = ffs(
					na->compression_block_size) - 1;
		}
		NAttrSetInitialized(na);
	}
}