tillOffset := erasure.ShardFileOffset(0, partSize, partSize)
			readers := make([]io.ReaderAt, len(latestDisks))
			prefer := make([]bool, len(latestDisks))
			checksumAlgo := erasureInfo.GetChecksumInfo(partNumber).Algorithm
			for i, disk := range latestDisks {
				if disk == OfflineDisk {
					continue
				}

//
// 4. __outdated__           - returned by outDatedDisk, provided []StorageAPI
//                             returned by diskWithAllParts is passed for latestDisks.
//    - has an old copy of xl.meta
//    - doesn't have xl.meta (errFileNotFound)
//    - has the latest xl.meta but one or more parts are corrupt
//