+/** efi_mem_carve_out - unmap memory region
+ *
+ * @map: memory map
+ * @carve_desc: memory region to unmap
+ * @overlap_only_ram: the carved out region may only overlap RAM
+ * Return Value: the number of overlapping pages which have been
+ * removed from the map,
+ * EFI_CARVE_NO_OVERLAP, if the regions don't overlap,
+ * EFI_CARVE_OVERLAPS_NONRAM, if the carve and map overlap,
+ * and the map contains anything but free ram
+ * (only when overlap_only_ram is true),
+ * EFI_CARVE_LOOP_AGAIN, if the mapping list should be
+ * traversed again, as it has been altered.