if errors.Is(err, errVolumeNotFound) {
			return pi, toObjectErr(err, bucket)
		}
		return pi, toObjectErr(err, bucket, object, uploadID)
	}

	// Write lock for this part ID, only hold it if we are planning to read from the
	// streamto avoid any concurrent updates.
	//
	// Must be held throughout this call.
	partIDLock := er.NewNSLock(bucket, pathJoin(object, uploadID, strconv.Itoa(partID)))