// Instantiate posix object to manage a disk
	fs, err := newLocalXLStorage(dir)
	if err != nil {
		t.Fatal(err)
	}

	// Create volume to use in conjunction with other StorageAPI's file API(s)
	err = fs.MakeVol(context.Background(), "voldir")
	if err != nil {
		t.Fatal(err)
	}

	for i, test := range testCases {
		t.Run(fmt.Sprint(i), func(t *testing.T) {

		// Make a volume entry on all underlying storage disks.
		for index := range localDrives {
			index := index
			g.Go(func() error {
				if beforeState[index] == madmin.DriveStateMissing {
					err := localDrives[index].MakeVol(ctx, bucket)
					if err == nil {
						afterState[index] = madmin.DriveStateOk
					}
					return err
				}
				return errs[index]
			}, index)
		}

		errs = g.Wait()
	}

	tmpDir := t.TempDir()

	volume := "testvol"
	filePath := "testfile"

	disk, err := newLocalXLStorage(tmpDir)
	if err != nil {
		t.Fatal(err)
	}

	disk.MakeVol(context.Background(), volume)

	writer := newBitrotWriter(disk, "", volume, filePath, 35, bitrotAlgo, 10)

	_, err = writer.Write([]byte("aaaaaaaaaa"))
	if err != nil {
		t.Fatal(err)
	}

	NSScanner(ctx context.Context, cache dataUsageCache, updates chan<- dataUsageEntry, scanMode madmin.HealScanMode, shouldSleep func() bool) (dataUsageCache, error)

	// Volume operations.
	MakeVol(ctx context.Context, volume string) (err error)
	MakeVolBulk(ctx context.Context, volumes ...string) (err error)
	ListVols(ctx context.Context) (vols []VolInfo, err error)