diff --git a/src/filo-fs-ext2.ads b/src/filo-fs-ext2.ads
index b1f1544..fbe6a35 100644
--- a/src/filo-fs-ext2.ads
+++ b/src/filo-fs-ext2.ads
@@ -55,9 +55,11 @@
    -- to 64 1KiB blocks.
    -- Cache entries can be used for blocks that map logical block offets
    -- to physical ones. Then we note the first logical block offset mapped
-   -- by the cached block.
+   -- by the cached block. Otherwise, we use their physical offset.
+   type Cache_Label is new Unsigned_64;
    subtype Block_Cache_Index is Natural range 0 .. 63;
-   type Block_Cache_Type is array (Block_Cache_Index) of FSBlock_Logical;
+   type Cache_Label_Logical is array (Block_Cache_Index) of Boolean;
+   type Cache_Label_Array is array (Block_Cache_Index) of Cache_Label;
 
    -- Same as the 12 direct + 3 indirect blocks times 4B:
    subtype Inode_Extents_Index is Natural range 0 .. 59;
@@ -72,17 +74,18 @@
 
    type T is record
       S : State;
-      Part_Len          : Partition_Length := 0;
-      First_Data_Block  : FSBlock_Offset := 0;
-      Block_Size_Bits   : Log_Block_Size := 10;
-      Inodes_Per_Group  : Positive := 1;
-      Inode_Size        : Ext2.Inode_Size := Ext2.Inode_Size'First;
-      Desc_Size         : Ext2.Desc_Size := Ext2.Desc_Size'First;
-      Feature_Extents   : Boolean := False;
-      Feature_64Bit     : Boolean := False;
-      Inode             : Inode_Info := (others => <>);
-      Block_Cache_Index : Block_Cache_Type := (others => 0);
-      Block_Cache       : Buffer_Type (Max_Block_Index) := (others => 16#00#);
+      Part_Len             : Partition_Length := 0;
+      First_Data_Block     : FSBlock_Offset := 0;
+      Block_Size_Bits      : Log_Block_Size := 10;
+      Inodes_Per_Group     : Positive := 1;
+      Inode_Size           : Ext2.Inode_Size := Ext2.Inode_Size'First;
+      Desc_Size            : Ext2.Desc_Size := Ext2.Desc_Size'First;
+      Feature_Extents      : Boolean := False;
+      Feature_64Bit        : Boolean := False;
+      Inode                : Inode_Info := (others => <>);
+      Block_Cache_Logical  : Cache_Label_Logical := (others => False);
+      Block_Cache_Label    : Cache_Label_Array := (others => 0);
+      Block_Cache          : Buffer_Type (Max_Block_Index) := (others => 16#00#);
    end record;
 
 end FILO.FS.Ext2;