-extern Uint64 DrvUtil_ReadBlock(Uint64 Start, Uint64 Length, void *Buffer,\r
- tDrvUtil_Read_Callback ReadBlocks, Uint64 BlockSize, void *Argument);\r
+extern size_t DrvUtil_ReadBlock(Uint64 Start, size_t Length, void *Buffer,\r
+ tDrvUtil_Read_Callback ReadBlocks, size_t BlockSize, void *Argument);\r