if err != nil {
			if osErrToFileErr(err) == errFileNotFound {
				return nil
			}
			return osErrToFileErr(err)
		}
	}
	defer syscall.Close(fd)

	bufp := direntPool.Get()
	defer direntPool.Put(bufp)
	buf := *bufp

	boff := 0 // starting read position in buf
	nbuf := 0 // end valid data in buf

	for {
		if boff >= nbuf {
			boff = 0

		if o.prefixAll != "" {
			name = pathJoin(o.prefixAll, name)
		}

		// Do small files async
		n++
		if header.Size <= xioutil.MediumBlock {
			asyncWriters <- struct{}{}
			bufp := xioutil.ODirectPoolMedium.Get()
			b := (*bufp)[:header.Size]
			if _, err := io.ReadFull(tarReader, b); err != nil {
				return err
			}
			wg.Add(1)
			go func(name string, fi fs.FileInfo, b []byte) {

	// Calculate the size of the bitrot file and compare
	// it with the actual file size.
	if left != bitrotShardFileSize(partSize, shardSize, algo) {
		return errFileCorrupt
	}

	bufp := xioutil.ODirectPoolSmall.Get()
	defer xioutil.ODirectPoolSmall.Put(bufp)

	for left > 0 {
		// Read expected hash...
		h.Reset()
		n, err := io.ReadFull(r, hashBuf)
		if err != nil {