var index []byte
	if opts.IndexCB != nil {
		index = opts.IndexCB()
	}

	modTime := UTCNow()

	for i, w := range writers {
		if w == nil {
			// Make sure to avoid writing to disks which we couldn't complete in erasure.Encode()
			onlineDisks[i] = nil
			continue
		}
		partsMetadata[i].Data = inlineBuffers[i].Bytes()
		partsMetadata[i].AddObjectPart(1, "", n, data.ActualSize(), modTime, index, nil)
	}