// For any unexpected error, return checkPartUnknown (zero)
func (s *xlStorage) checkPart(volumeDir, path, dataDir string, partNum int, expectedSize int64, skipAccessCheck bool) (resp int) {
	partPath := pathJoin(path, dataDir, fmt.Sprintf("part.%d", partNum))
	filePath := pathJoin(volumeDir, partPath)
	st, err := Lstat(filePath)
	if err != nil {
		if osIsNotExist(err) {
			if !skipAccessCheck {

				var zb0004 uint8
				zb0004, err = dc.ReadUint8()
				if err != nil {
					err = msgp.WrapError(err, "BitrotChecksumAlgo")
					return
				}
				z.BitrotChecksumAlgo = ChecksumAlgo(zb0004)
			}
		case "PartNums":
			var zb0005 uint32
			zb0005, err = dc.ReadArrayHeader()
			if err != nil {
				err = msgp.WrapError(err, "PartNumbers")
				return
			}
			if cap(z.PartNumbers) >= int(zb0005) {

	BitrotChecksumAlgo ChecksumAlgo      `json:"CSumAlgo" msg:"CSumAlgo"`                        // Bitrot checksum algo
	PartNumbers        []int             `json:"PartNums" msg:"PartNums"`                        // Part Numbers
	PartETags          []string          `json:"PartETags" msg:"PartETags,allownil"`             // Part ETags