Intel Extensible Firmware Interface, Specification

Page: 112 / 494

Extensible Firmware Interface Specification
94 12/12/00 Version 1.02
3.7.2 ConvertPointer()
Summary
Determines the new virtual address that is to be used on subsequent memory accesses.
Prototype
EFI_STATUS
ConvertPointer (
IN UINTN DebugDisposition,
IN VOID **Address
);
Parameters
DebugDisposition
Supplies type information for the pointer being converted. See
"Related Definitions".
Address
A pointer to a pointer that is to be fixed to be the value needed
for the new virtual address mappings being applied.
Related Definitions
//*******************************************************
// EFI_OPTIONAL_PTR
//*******************************************************
#define EFI_OPTIONAL_PTR 0x00000001
Description
The
ConvertPointer()
function is used by an EFI component during the
SetVirtualAddressMap()
operation.
The
ConvertPointer()
function updates the current pointer pointed to by
Address
to be the
proper value for the new address map. Only runtime components need to perform this operation.
The
CreateEvent()
function is used to create an event that is to be notified when the address
map is changing. All pointers the component has allocated or assigned must be updated.
If the
EFI_OPTIONAL_PTR
flag is specified, the pointer being converted is allowed to be
NULL
.
Once all components have been notified of the address map change, firmware fixes any compiled in
pointers that are embedded in any runtime image.
Status Codes Returned
EFI_SUCCESS
The pointer pointed to by
Address
was modified.
EFI_NOT_FOUND
The pointer pointed to by
Address
was not found to be part
of the current memory map. This is normally fatal.
EFI_INVALID_PARAMETER One of the parameters has an invalid value.