Index:      index,
		Checksums:  r.ContentCRC(),
	}

	partFI, err := partInfo.MarshalMsg(nil)
	if err != nil {
		return pi, toObjectErr(err, minioMetaMultipartBucket, partPath)
	}

	// Serialize concurrent part uploads.
	partIDLock := er.NewNSLock(bucket, pathJoin(object, uploadID, strconv.Itoa(partID)))
	plkctx, err := partIDLock.GetLock(ctx, globalOperationTimeout)
	if err != nil {
		return PartInfo{}, err
	}

		//   inconsequential to the overall read operation.
		// - xl.meta metadata is still verified for quorum under lock()
		//   however writing the response doesn't need to serialize
		//   concurrent writers
		unlockOnDefer = true
		nsUnlocker = func() { lock.RUnlock(lkctx) }
	}

	fi, metaArr, onlineDisks, err := er.getObjectFileInfo(ctx, bucket, object, opts, true)
	if err != nil {