Intel Extensible Firmware Interface - Manual (Page 179)

Services — Boot Services
Version 1.10 12/01/02 5-81
UnloadImage()
Summary
Unloads an image.
Prototype
typedef
EFI_STATUS
UnloadImage (
IN EFI_HANDLE ImageHandle
);
Parameters
ImageHandle Handle that identifies the image to be unloaded.
Description
The UnloadImage() function unloads a previously loaded image.
There are three possible scenarios. If the image has not been started, the function unloads the
image and returns
EFI_SUCCESS .
If the image has been started and has an Unload() entry point, control is passed to that entry
point. If the image’s unload function returns EFI_SUCCESS , the image is unloaded; otherwise,
the error returned by the image’s unload function is returned to the caller. The image unload
function is responsible for freeing all allocated memory and ensuring that there are no references to
any freed memory, or to the image itself, before returning
EFI_SUCCESS .
If the image has been started and does not have an Unload() entry point, the function returns
EFI_UNSUPPORTED .
EFI 1.10 Extension
All of the protocols that were opened by ImageHandle using the boot service
OpenProtocol() are automatically closed with the boot service CloseProtocol() . If all of
the open protocols are closed, then EFI_SUCCESS is returned. If any call to
CloseProtocol() fails, then the error code from CloseProtocol() is returned.
Status Codes Returned
EFI_SUCCESS The image has been unloaded.
EFI_UNSUPPORTED The image has been started, and does not support unload.
EFI_INVALID_PARAMETER ImageHandle is not a valid image handle.
Exit code from Unload handler Exit code from the image’s unload function.