testReadFrom{fileOps{
						int64(1e10 - blockSize),
						strings.Repeat("\x00", blockSize-100) + strings.Repeat("0123456789", 10),
						int64(1e10 - blockSize),
						strings.Repeat("\x00", blockSize-100) + strings.Repeat("0123456789", 10),
						int64(1e10 - blockSize),
						strings.Repeat("\x00", blockSize-100) + strings.Repeat("0123456789", 10),
						int64(1e10 - blockSize),

	if len(ticketKeys) == 0 {
		return nil, errors.New("tls: internal error: session ticket keys unavailable")
	}

	encrypted := make([]byte, aes.BlockSize+len(state)+sha256.Size)
	iv := encrypted[:aes.BlockSize]
	ciphertext := encrypted[aes.BlockSize : len(encrypted)-sha256.Size]
	authenticated := encrypted[:len(encrypted)-sha256.Size]
	macBytes := encrypted[len(encrypted)-sha256.Size:]

		ptrs[i] = new(obj)
	}

	writeBarrierBenchmark(b, func() {
		const blockSize = 1024
		var pos int
		for i := 0; i < b.N; i += blockSize {
			// Rotate block.
			block := ptrs[pos : pos+blockSize]
			first := block[0]
			copy(block, block[1:])
			block[blockSize-1] = first

			pos += blockSize
			if pos+blockSize > len(ptrs) {
				pos = 0
			}

			runtime.Gosched()
		}
	})

// details.
func (g *gcmAsm) Seal(dst, nonce, plaintext, data []byte) []byte {
	if len(nonce) != g.nonceSize {
		panic("crypto/cipher: incorrect nonce length given to GCM")
	}
	if uint64(len(plaintext)) > ((1<<32)-2)*BlockSize {
		panic("crypto/cipher: message too large for GCM")
	}

	ret, out := sliceForAppend(dst, len(plaintext)+g.tagSize)
	if alias.InexactOverlap(out[:len(plaintext)], plaintext) {

		// max requests per node is calculated as
		// total_ram / ram_per_request
		blockSize := xioutil.LargeBlock + xioutil.SmallBlock
		if legacy {
			// ram_per_request is (1MiB+32KiB) * driveCount \
			//    + 2 * 10MiB (default erasure block size v1) + 2 * 1MiB (default erasure block size v2)
			apiRequestsMaxPerNode = int(maxMem / uint64(maxSetDrives*blockSize+int(blockSizeV1*2+blockSizeV2*2)))
		} else {

	case size < fi.Erasure.BlockSize:
		// No need to allocate fully fi.Erasure.BlockSize buffer if the incoming data is smaller.
		buffer = make([]byte, size, 2*size+int64(fi.Erasure.ParityBlocks+fi.Erasure.DataBlocks-1))
	}

	if len(buffer) > int(fi.Erasure.BlockSize) {
		buffer = buffer[:fi.Erasure.BlockSize]
	}
	writers := make([]io.Writer, len(onlineDisks))
	for i, disk := range onlineDisks {
		if disk == nil {

	if totalLength == -1 {
		return -1
	}
	numShards := totalLength / e.BlockSize
	lastBlockSize := totalLength % e.BlockSize
	lastShardSize := ceilFrac(lastBlockSize, int64(e.DataBlocks))
	return numShards*e.ShardSize() + lastShardSize
}

// ShardSize - returns actual shared size from erasure blockSize.
func (e ErasureInfo) ShardSize() int64 {
	return ceilFrac(e.BlockSize, int64(e.DataBlocks))
}

	}

	if cipher, ok := cipher.(gcmAble); ok {
		return cipher.NewGCM(nonceSize, tagSize)
	}

	if cipher.BlockSize() != gcmBlockSize {
		return nil, errors.New("cipher: NewGCM requires 128-bit block cipher")
	}

	var key [gcmBlockSize]byte
	cipher.Encrypt(key[:], key[:])

func shardSize(blockSize, dataBlocks int) (sz int) {
	if dataBlocks == 0 {
		// do nothing on invalid input
		return
	}
	// Make denominator positive
	if dataBlocks < 0 {
		blockSize = -blockSize
		dataBlocks = -dataBlocks
	}
	sz = blockSize / dataBlocks
	if blockSize > 0 && blockSize%dataBlocks != 0 {
		sz++
	}
	return
}

type cthWrapper struct {
	h constantTimeHash
}

func (c *cthWrapper) Size() int                   { return c.h.Size() }
func (c *cthWrapper) BlockSize() int              { return c.h.BlockSize() }
func (c *cthWrapper) Reset()                      { c.h.Reset() }
func (c *cthWrapper) Write(p []byte) (int, error) { return c.h.Write(p) }