PVOID MiFindEmptyAddressRangeDownTree( IN SIZE_T SizeOfRange, IN PVOID HighestAddressToEndAt, IN ULONG_PTR Alignment, IN PMMADDRESS_NODE Root ); Routine Description: The function examines the virtual address descriptors to locate an unused range of the specified size and returns the starting address of the range. The function examines from the high addresses down and ensures that starting address is less than the specified address. Arguments: SizeOfRange - Supplies the size in bytes of the range to locate. HighestAddressToEndAt - Supplies the virtual address that limits the value of the ending address. The ending address of the located range must be less than this address. Alignment - Supplies the alignment for the address. Must be a power of 2 and greater than the page_size. Root - Supplies the root of the tree to search through. Return Value: Returns the starting address of a suitable range.