diff --git a/metropolis/pkg/fat32/utils.go b/metropolis/pkg/fat32/utils.go
new file mode 100644
index 0000000..833665c
--- /dev/null
+++ b/metropolis/pkg/fat32/utils.go
@@ -0,0 +1,74 @@
+package fat32
+
+import (
+	"fmt"
+	"io"
+	"time"
+)
+
+// Wraps a writer and provides support for writing padding up to a specified
+// alignment.
+// TODO(lorenz): Implement WriterTo when w implements it to allow for copy
+// offload
+type blockWriter struct {
+	w io.Writer
+	n int64
+}
+
+func newBlockWriter(w io.Writer) *blockWriter {
+	return &blockWriter{w: w}
+}
+
+func (b *blockWriter) Write(p []byte) (n int, err error) {
+	n, err = b.w.Write(p)
+	b.n += int64(n)
+	return
+}
+
+func (b *blockWriter) FinishBlock(alignment int64, mustZero bool) (err error) {
+	requiredBytes := (alignment - (b.n % alignment)) % alignment
+	if requiredBytes == 0 {
+		return nil
+	}
+	// Do not actually write out zeroes if not necessary
+	if s, ok := b.w.(io.Seeker); ok && !mustZero {
+		if _, err := s.Seek(requiredBytes-1, io.SeekCurrent); err != nil {
+			return fmt.Errorf("failed to seek to create hole for empty block: %w", err)
+		}
+		if _, err := b.w.Write([]byte{0x00}); err != nil {
+			return fmt.Errorf("failed to write last byte to create hole: %w", err)
+		}
+		b.n += requiredBytes
+		return
+	}
+	emptyBuf := make([]byte, 1*1024*1024)
+	for requiredBytes > 0 {
+		curBlockBytes := requiredBytes
+		if curBlockBytes > int64(len(emptyBuf)) {
+			curBlockBytes = int64(len(emptyBuf))
+		}
+		_, err = b.Write(emptyBuf[:curBlockBytes])
+		if err != nil {
+			return
+		}
+		requiredBytes -= curBlockBytes
+	}
+	return
+}
+
+// timeToMsDosTime converts a time.Time to an MS-DOS date and time.
+// The resolution is 2s with fTime and 10ms if fTenMils is also used.
+// See: http://msdn.microsoft.com/en-us/library/ms724274(v=VS.85).aspx
+func timeToMsDosTime(t time.Time) (fDate uint16, fTime uint16, fTenMils uint8) {
+	t = t.In(time.UTC)
+	if t.Year() < 1980 {
+		t = time.Date(1980, 1, 1, 0, 0, 0, 0, time.UTC)
+	}
+	if t.Year() > 2107 {
+		t = time.Date(2107, 12, 31, 23, 59, 59, 0, time.UTC)
+	}
+	fDate = uint16(t.Day() + int(t.Month())<<5 + (t.Year()-1980)<<9)
+	fTime = uint16(t.Second()/2 + t.Minute()<<5 + t.Hour()<<11)
+	fTenMils = uint8(t.Nanosecond()/1e7 + (t.Second()%2)*100)
+	return
+}