/**
Gets LBA of block and offset by given address.
This function gets the Logical Block Address (LBA) of firmware
volume block containing the given address, and the offset of
address on the block.
@param[in] Address Address which should be contained
by returned FVB handle.
@param[out] Lba The pointer to LBA for output.
@param[out] Offset The pointer to offset for output.
@retval EFI_SUCCESS LBA and offset successfully returned.
@retval EFI_NOT_FOUND Failed to find FVB handle by address.
@retval EFI_ABORTED Failed to find valid LBA and offset.
**/
EFI_STATUS
GetLbaAndOffsetByAddress (
IN EFI_PHYSICAL_ADDRESS Address,
OUT EFI_LBA *Lba,
OUT UINTN *Offset
)
{
EFI_STATUS Status;
EFI_HANDLE FvbHandle;
EFI_PHYSICAL_ADDRESS FvbBaseAddress;
EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *Fvb;
EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader;
EFI_FV_BLOCK_MAP_ENTRY *FvbMapEntry;
UINT32 LbaIndex;
*Lba = (EFI_LBA) (-1);
*Offset = 0;
//
// Gets firmware volume block handle by given address.
//
Status = GetFvbHandleByAddress (Address, &FvbHandle);
if (EFI_ERROR (Status)) {
return Status;
}
Status = gBS->HandleProtocol (
FvbHandle,
&gEfiFirmwareVolumeBlockProtocolGuid,
(VOID **) &Fvb
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Get the Base Address of FV
//
Status = Fvb->GetPhysicalAddress (Fvb, &FvbBaseAddress);
if (EFI_ERROR (Status)) {
return Status;
}
FwVolHeader = (EFI_FIRMWARE_VOLUME_HEADER *) ((UINTN) FvbBaseAddress);
//
// Get the (LBA, Offset) of Address
//
if ((Address >= FvbBaseAddress) && (Address <= (FvbBaseAddress + FwVolHeader->FvLength))) {
if ((FwVolHeader->FvLength) > (FwVolHeader->HeaderLength)) {
//
// BUGBUG: Assume one FV has one type of BlockLength
//
FvbMapEntry = &FwVolHeader->BlockMap[0];
for (LbaIndex = 1; LbaIndex <= FvbMapEntry->NumBlocks; LbaIndex += 1) {
if (Address < (FvbBaseAddress + FvbMapEntry->Length * LbaIndex)) {
//
// Found the (Lba, Offset)
//
*Lba = LbaIndex - 1;
*Offset = (UINTN) (Address - (FvbBaseAddress + FvbMapEntry->Length * (LbaIndex - 1)));
return EFI_SUCCESS;
}
}
}
}
return EFI_ABORTED;
}
/**
Writes a buffer to variable storage space.
This function writes a buffer to variable storage space into firmware
volume block device. The destination is specified by parameter
VariableBase. Fault Tolerant Write protocol is used for writing.
@param[in] VariableBase The base address of the variable to write.
@param[in] Buffer Points to the data buffer.
@param[in] BufferSize The number of bytes of the data Buffer.
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_NOT_FOUND Fail to locate Fault Tolerant Write protocol.
@retval Other The function could not complete successfully.
**/
EFI_STATUS
FtwVariableSpace (
IN EFI_PHYSICAL_ADDRESS VariableBase,
IN UINT8 *Buffer,
IN UINTN BufferSize
)
{
EFI_STATUS Status;
EFI_HANDLE FvbHandle;
EFI_LBA VarLba;
UINTN VarOffset;
UINT8 *FtwBuffer;
UINTN FtwBufferSize;
EFI_FAULT_TOLERANT_WRITE_PROTOCOL *FtwProtocol;
//
// Locate Fault Tolerant Write protocol
//
Status = gBS->LocateProtocol (
&gEfiFaultTolerantWriteProtocolGuid,
NULL,
(VOID **) &FtwProtocol
);
if (EFI_ERROR (Status)) {
return EFI_NOT_FOUND;
}
//
// Gets firmware volume block handle by VariableBase.
//
Status = GetFvbHandleByAddress (VariableBase, &FvbHandle);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Gets LBA of block and offset by VariableBase.
//
Status = GetLbaAndOffsetByAddress (VariableBase, &VarLba, &VarOffset);
if (EFI_ERROR (Status)) {
return EFI_ABORTED;
}
//
// Prepare for the variable data
//
FtwBufferSize = ((VARIABLE_STORE_HEADER *) ((UINTN) VariableBase))->Size;
FtwBuffer = AllocatePool (FtwBufferSize);
if (FtwBuffer == NULL) {
return EFI_OUT_OF_RESOURCES;
}
SetMem (FtwBuffer, FtwBufferSize, (UINT8) 0xff);
CopyMem (FtwBuffer, Buffer, BufferSize);
//
// FTW write record
//
Status = FtwProtocol->Write (
FtwProtocol,
VarLba, // LBA
VarOffset, // Offset
FtwBufferSize, // NumBytes,
NULL,
FvbHandle,
FtwBuffer
);
FreePool (FtwBuffer);
return Status;
}
EFI_STATUS
FtwVariableSpace (
IN EFI_PHYSICAL_ADDRESS VariableBase,
IN UINT8 *Buffer,
IN UINTN BufferSize
)
/*++
Routine Description:
Write a buffer to Variable space, in the working block.
Arguments:
FvbHandle - Indicates a handle to FVB to access variable store
Buffer - Point to the input buffer
BufferSize - The number of bytes of the input Buffer
Returns:
EFI_SUCCESS - The function completed successfully
EFI_ABORTED - The function could not complete successfully
EFI_NOT_FOUND - Locate FVB protocol by handle fails
--*/
{
EFI_STATUS Status;
EFI_HANDLE FvbHandle;
EFI_FTW_LITE_PROTOCOL *FtwLiteProtocol;
EFI_LBA VarLba;
UINTN VarOffset;
UINT8 *FtwBuffer;
UINTN FtwBufferSize;
//
// Locate fault tolerant write protocol
//
Status = gBS->LocateProtocol (
&gEfiFaultTolerantWriteLiteProtocolGuid,
NULL,
&FtwLiteProtocol
);
if (EFI_ERROR (Status)) {
return EFI_NOT_FOUND;
}
//
// Locate Fvb handle by address
//
Status = GetFvbHandleByAddress (VariableBase, &FvbHandle);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Get LBA and Offset by address
//
Status = GetLbaAndOffsetByAddress (VariableBase, &VarLba, &VarOffset);
if (EFI_ERROR (Status)) {
return EFI_ABORTED;
}
//
// Prepare for the variable data
//
FtwBufferSize = ((VARIABLE_STORE_HEADER *) ((UINTN) VariableBase))->Size;
Status = gBS->AllocatePool (EfiRuntimeServicesData, FtwBufferSize, &FtwBuffer);
if (EFI_ERROR (Status)) {
return EFI_OUT_OF_RESOURCES;
}
EfiSetMem (FtwBuffer, FtwBufferSize, (UINT8) 0xff);
EfiCopyMem (FtwBuffer, Buffer, BufferSize);
//
// FTW write record
//
Status = FtwLiteProtocol->Write (
FtwLiteProtocol,
FvbHandle,
VarLba, // LBA
VarOffset, // Offset
&FtwBufferSize, // NumBytes,
FtwBuffer
);
gBS->FreePool (FtwBuffer);
return Status;
}
