Intel Extensible Firmware Interface - Manual (Page 498)

Extensible Firmware Interface Specification
12-80 12/01/02 Version 1.10
EFI_PCI_IO_PROTOCOL.Unmap()
Summary
Completes the Map() operation and releases any corresponding resources.
Prototype
typedef
EFI_STATUS
(EFIAPI *EFI_PCI_IO_PROTOCOL_UNMAP) (
IN EFI_PCI_IO_PROTOCOL
*This,
IN VOID *Mapping
);
Parameters
This A pointer to the EFI_PCI_IO_PROTOCOL instance. Type
EFI_PCI_IO_PROTOCOL is defined in Section 12.4.
Mapping The mapping value returned from Map() .
Description
The Unmap() function completes the Map() operation and releases any corresponding resources.
If the operation was an EfiPciIoOperationBusMasterWrite , the data is committed to the
target system memory. Any resources used for the mapping are freed.
Status Codes Returned
EFI_SUCCESS The range was unmapped.
EFI_INVALID_PARAMETER HostAddress is not a value that was returned by Map() .
EFI_DEVICE_ERROR The data was not committed to the target system memory.