diff --git a/kernel/drivertools.cc b/kernel/drivertools.cc
index 29efab01d14..27ebd20b284 100644
--- a/kernel/drivertools.cc
+++ b/kernel/drivertools.cc
@@ -703,6 +703,38 @@ bool DriveChunkMarker::try_append(DriveChunkMarker const &chunk)
   return true;
 }
 
+DriveChunkMarker::DriveChunkMarker(int marker, int offset, int width)
+    : marker(marker), offset(offset), width(width) {}
+
+DriveChunkMarker::DriveChunkMarker(DriveBitMarker const &bit)
+    : marker(bit.marker), offset(bit.offset), width(1) {}
+
+int DriveChunkMarker::size() const { return width; }
+
+DriveBitMarker DriveChunkMarker::operator[](int i) const
+{
+    log_assert(i >= 0 && i < width);
+    return DriveBitMarker(marker, offset + i);
+}
+
+bool DriveChunkMarker::operator==(const DriveChunkMarker &other) const
+{
+    return marker == other.marker && offset == other.offset && width == other.width;
+}
+
+bool DriveChunkMarker::operator<(const DriveChunkMarker &other) const
+{
+    if (marker != other.marker)
+        return marker < other.marker;
+    if (width != other.width)
+        return width < other.width;
+    return offset < other.offset;
+}
+
+unsigned int DriveChunkMarker::hash() const
+{
+    return mkhash_add(mkhash(marker, width), offset);
+}
 
 bool DriveChunkMultiple::can_append(DriveBitMultiple const &bit) const
 {
diff --git a/kernel/drivertools.h b/kernel/drivertools.h
index f98860c51d7..4f6c7a7befe 100644
--- a/kernel/drivertools.h
+++ b/kernel/drivertools.h
@@ -245,45 +245,21 @@ struct DriveChunkPort
 
 struct DriveChunkMarker
 {
-  int marker;
-  int offset;
-  int width;
-
-  DriveChunkMarker(int marker, int offset, int width) :
-    marker(marker), offset(offset), width(width) {}
-  DriveChunkMarker(DriveBitMarker const &bit) :
-    marker(bit.marker), offset(bit.offset), width(1) {}
-
-  int size() const { return width; }
-
-  DriveBitMarker operator[](int i) const
-  {
-    log_assert(i >= 0 && i < width);
-    return DriveBitMarker(marker, offset + i);
-  }
-
-  bool can_append(DriveBitMarker const &bit) const;
-  bool try_append(DriveBitMarker const &bit);
-  bool try_append(DriveChunkMarker const &chunk);
-
-  bool operator==(const DriveChunkMarker &other) const
-  {
-    return marker == other.marker && offset == other.offset && width == other.width;
-  }
+    int marker;
+    int offset;
+    int width;
 
-  bool operator<(const DriveChunkMarker &other) const
-  {
-    if (marker != other.marker)
-      return marker < other.marker;
-    if (width != other.width)
-      return width < other.width;
-    return offset < other.offset;
-  }
+    DriveChunkMarker(int marker, int offset, int width);
+    DriveChunkMarker(DriveBitMarker const &bit);
 
-  unsigned int hash() const
-  {
-    return mkhash_add(mkhash(marker, width), offset);
-  }
+    int size() const;
+    DriveBitMarker operator[](int i) const;
+    bool can_append(DriveBitMarker const &bit) const;
+    bool try_append(DriveBitMarker const &bit);
+    bool try_append(DriveChunkMarker const &chunk);
+    bool operator==(const DriveChunkMarker &other) const;
+    bool operator<(const DriveChunkMarker &other) const;
+    unsigned int hash() const;
 };
 
 struct DriveChunkMultiple