partIDLock := er.NewNSLock(bucket, pathJoin(object, uploadID, strconv.Itoa(partID)))
	plkctx, err := partIDLock.GetLock(ctx, globalOperationTimeout)
	if err != nil {
		return PartInfo{}, err
	}
	pctx := plkctx.Context()
	defer partIDLock.Unlock(plkctx)

	onlineDisks := er.getDisks()
	writeQuorum := fi.WriteQuorum(er.defaultWQuorum())

	if cs := fi.Metadata[hash.MinIOMultipartChecksum]; cs != "" {