audk/MdeModulePkg/Universal/Variable/Pei/Variable.c

623 lines
18 KiB
C

/** @file
Implement ReadOnly Variable Services required by PEIM and install
PI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.
Copyright (c) 2006 - 2008 Intel Corporation. <BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
Module Name:
**/
#include "Variable.h"
//
// Module globals
//
EFI_PEI_READ_ONLY_VARIABLE2_PPI mVariablePpi = {
PeiGetVariable,
PeiGetNextVariableName
};
EFI_PEI_PPI_DESCRIPTOR mPpiListVariable = {
(EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
&gEfiPeiReadOnlyVariable2PpiGuid,
&mVariablePpi
};
EFI_GUID mEfiVariableIndexTableGuid = EFI_VARIABLE_INDEX_TABLE_GUID;
/**
Provide the functionality of the variable services.
@param FileHandle Handle of the file being invoked.
Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
@param PeiServices General purpose services available to every PEIM.
@retval EFI_SUCCESS If the interface could be successfully installed
@retval Others Returned from PeiServicesInstallPpi()
**/
EFI_STATUS
EFIAPI
PeimInitializeVariableServices (
IN EFI_PEI_FILE_HANDLE FileHandle,
IN CONST EFI_PEI_SERVICES **PeiServices
)
{
//
// Publish the variable capability to other modules
//
return PeiServicesInstallPpi (&mPpiListVariable);
}
/**
This code gets the pointer to the first variable memory pointer byte.
@param VarStoreHeader Pointer to the Variable Store Header.
@return VARIABLE_HEADER* pointer to last unavailable Variable Header.
**/
VARIABLE_HEADER *
GetStartPointer (
IN VARIABLE_STORE_HEADER *VarStoreHeader
)
{
//
// The end of variable store
//
return (VARIABLE_HEADER *) HEADER_ALIGN (VarStoreHeader + 1);
}
/**
This code gets the pointer to the last variable memory pointer byte.
@param VarStoreHeader Pointer to the Variable Store Header.
@return VARIABLE_HEADER* pointer to last unavailable Variable Header.
**/
VARIABLE_HEADER *
GetEndPointer (
IN VARIABLE_STORE_HEADER *VarStoreHeader
)
{
//
// The end of variable store
//
return (VARIABLE_HEADER *) HEADER_ALIGN ((UINTN) VarStoreHeader + VarStoreHeader->Size);
}
/**
This code checks if variable header is valid or not.
@param Variable Pointer to the Variable Header.
@retval TRUE Variable header is valid.
@retval FALSE Variable header is not valid.
**/
BOOLEAN
IsValidVariableHeader (
IN VARIABLE_HEADER *Variable
)
{
if (Variable == NULL || Variable->StartId != VARIABLE_DATA ) {
return FALSE;
}
return TRUE;
}
/**
This code gets the size of name of variable.
@param Variable Pointer to the Variable Header.
@return Size of variable in bytes in type UINTN.
**/
UINTN
NameSizeOfVariable (
IN VARIABLE_HEADER *Variable
)
{
if (Variable->State == (UINT8) (-1) ||
Variable->DataSize == (UINT32) -1 ||
Variable->NameSize == (UINT32) -1 ||
Variable->Attributes == (UINT32) -1) {
return 0;
}
return (UINTN) Variable->NameSize;
}
/**
This code gets the size of data of variable.
@param Variable Pointer to the Variable Header.
@return Size of variable in bytes in type UINTN.
**/
UINTN
DataSizeOfVariable (
IN VARIABLE_HEADER *Variable
)
{
if (Variable->State == (UINT8) -1 ||
Variable->DataSize == (UINT32) -1 ||
Variable->NameSize == (UINT32) -1 ||
Variable->Attributes == (UINT32) -1) {
return 0;
}
return (UINTN) Variable->DataSize;
}
/**
This code gets the pointer to the variable name.
@param Variable Pointer to the Variable Header.
@return A CHAR16* pointer to Variable Name.
**/
CHAR16 *
GetVariableNamePtr (
IN VARIABLE_HEADER *Variable
)
{
return (CHAR16 *) (Variable + 1);
}
/**
This code gets the pointer to the variable data.
@param Variable Pointer to the Variable Header.
@return A UINT8* pointer to Variable Data.
**/
UINT8 *
GetVariableDataPtr (
IN VARIABLE_HEADER *Variable
)
{
UINTN Value;
//
// Be careful about pad size for alignment
//
Value = (UINTN) GetVariableNamePtr (Variable);
Value += NameSizeOfVariable (Variable);
Value += GET_PAD_SIZE (NameSizeOfVariable (Variable));
return (UINT8 *) Value;
}
/**
This code gets the pointer to the next variable header.
@param Variable Pointer to the Variable Header.
@return A VARIABLE_HEADER* pointer to next variable header.
**/
VARIABLE_HEADER *
GetNextVariablePtr (
IN VARIABLE_HEADER *Variable
)
{
UINTN Value;
if (!IsValidVariableHeader (Variable)) {
return NULL;
}
Value = (UINTN) GetVariableDataPtr (Variable);
Value += DataSizeOfVariable (Variable);
Value += GET_PAD_SIZE (DataSizeOfVariable (Variable));
//
// Be careful about pad size for alignment
//
return (VARIABLE_HEADER *) HEADER_ALIGN (Value);
}
/**
This code gets the pointer to the variable name.
@param VarStoreHeader Pointer to the Variable Store Header.
@retval EfiRaw Variable store is raw
@retval EfiValid Variable store is valid
@retval EfiInvalid Variable store is invalid
**/
VARIABLE_STORE_STATUS
GetVariableStoreStatus (
IN VARIABLE_STORE_HEADER *VarStoreHeader
)
{
if (VarStoreHeader->Signature == VARIABLE_STORE_SIGNATURE &&
VarStoreHeader->Format == VARIABLE_STORE_FORMATTED &&
VarStoreHeader->State == VARIABLE_STORE_HEALTHY
) {
return EfiValid;
}
if (VarStoreHeader->Signature == 0xffffffff &&
VarStoreHeader->Size == 0xffffffff &&
VarStoreHeader->Format == 0xff &&
VarStoreHeader->State == 0xff
) {
return EfiRaw;
} else {
return EfiInvalid;
}
}
/**
This function compares a variable with variable entries in database.
@param Variable Pointer to the variable in our database
@param VariableName Name of the variable to compare to 'Variable'
@param VendorGuid GUID of the variable to compare to 'Variable'
@param PtrTrack Variable Track Pointer structure that contains Variable Information.
@retval EFI_SUCCESS Found match variable
@retval EFI_NOT_FOUND Variable not found
**/
EFI_STATUS
CompareWithValidVariable (
IN VARIABLE_HEADER *Variable,
IN CONST CHAR16 *VariableName,
IN CONST EFI_GUID *VendorGuid,
OUT VARIABLE_POINTER_TRACK *PtrTrack
)
{
VOID *Point;
if (VariableName[0] == 0) {
PtrTrack->CurrPtr = Variable;
return EFI_SUCCESS;
} else {
//
// Don't use CompareGuid function here for performance reasons.
// Instead we compare the GUID a UINT32 at a time and branch
// on the first failed comparison.
//
if ((((INT32 *) VendorGuid)[0] == ((INT32 *) &Variable->VendorGuid)[0]) &&
(((INT32 *) VendorGuid)[1] == ((INT32 *) &Variable->VendorGuid)[1]) &&
(((INT32 *) VendorGuid)[2] == ((INT32 *) &Variable->VendorGuid)[2]) &&
(((INT32 *) VendorGuid)[3] == ((INT32 *) &Variable->VendorGuid)[3])
) {
ASSERT (NameSizeOfVariable (Variable) != 0);
Point = (VOID *) GetVariableNamePtr (Variable);
if (CompareMem (VariableName, Point, NameSizeOfVariable (Variable)) == 0) {
PtrTrack->CurrPtr = Variable;
return EFI_SUCCESS;
}
}
}
return EFI_NOT_FOUND;
}
/**
This code finds variable in storage blocks (Non-Volatile).
@param PeiServices General purpose services available to every PEIM.
@param VariableName Name of the variable to be found
@param VendorGuid Vendor GUID to be found.
@param PtrTrack Variable Track Pointer structure that contains Variable Information.
@retval EFI_SUCCESS Variable found successfully
@retval EFI_NOT_FOUND Variable not found
@retval EFI_INVALID_PARAMETER Invalid variable name
**/
EFI_STATUS
FindVariable (
IN CONST EFI_PEI_SERVICES **PeiServices,
IN CONST CHAR16 *VariableName,
IN CONST EFI_GUID *VendorGuid,
OUT VARIABLE_POINTER_TRACK *PtrTrack
)
{
EFI_HOB_GUID_TYPE *GuidHob;
VARIABLE_STORE_HEADER *VariableStoreHeader;
VARIABLE_HEADER *Variable;
VARIABLE_HEADER *MaxIndex;
VARIABLE_INDEX_TABLE *IndexTable;
UINT32 Count;
UINT8 *VariableBase;
if (VariableName != 0 && VendorGuid == NULL) {
return EFI_INVALID_PARAMETER;
}
//
// No Variable Address equals zero, so 0 as initial value is safe.
//
MaxIndex = 0;
GuidHob = GetFirstGuidHob (&mEfiVariableIndexTableGuid);
if (GuidHob == NULL) {
IndexTable = BuildGuidHob (&mEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
IndexTable->Length = 0;
IndexTable->StartPtr = NULL;
IndexTable->EndPtr = NULL;
IndexTable->GoneThrough = 0;
} else {
IndexTable = GET_GUID_HOB_DATA (GuidHob);
for (Count = 0; Count < IndexTable->Length; Count++) {
MaxIndex = GetVariableByIndex (IndexTable, Count);
if (CompareWithValidVariable (MaxIndex, VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
PtrTrack->StartPtr = IndexTable->StartPtr;
PtrTrack->EndPtr = IndexTable->EndPtr;
return EFI_SUCCESS;
}
}
if (IndexTable->GoneThrough != 0) {
return EFI_NOT_FOUND;
}
}
//
// If not found in HOB, then let's start from the MaxIndex we've found.
//
if (MaxIndex != NULL) {
Variable = GetNextVariablePtr (MaxIndex);
} else {
if ((IndexTable->StartPtr != NULL) || (IndexTable->EndPtr != NULL)) {
Variable = IndexTable->StartPtr;
} else {
VariableBase = (UINT8 *) (UINTN) PcdGet32 (PcdFlashNvStorageVariableBase);
VariableStoreHeader = (VARIABLE_STORE_HEADER *) (VariableBase + \
((EFI_FIRMWARE_VOLUME_HEADER *) (VariableBase)) -> HeaderLength);
if (GetVariableStoreStatus (VariableStoreHeader) != EfiValid) {
return EFI_UNSUPPORTED;
}
if (~VariableStoreHeader->Size == 0) {
return EFI_NOT_FOUND;
}
//
// Find the variable by walk through non-volatile variable store
//
IndexTable->StartPtr = GetStartPointer (VariableStoreHeader);
IndexTable->EndPtr = GetEndPointer (VariableStoreHeader);
//
// Start Pointers for the variable.
// Actual Data Pointer where data can be written.
//
Variable = IndexTable->StartPtr;
}
}
//
// Find the variable by walk through non-volatile variable store
//
PtrTrack->StartPtr = IndexTable->StartPtr;
PtrTrack->EndPtr = IndexTable->EndPtr;
while (IsValidVariableHeader (Variable) && (Variable <= IndexTable->EndPtr)) {
if (Variable->State == VAR_ADDED) {
//
// Record Variable in VariableIndex HOB
//
if (IndexTable->Length < VARIABLE_INDEX_TABLE_VOLUME) {
VariableIndexTableUpdate (IndexTable, Variable);
}
if (CompareWithValidVariable (Variable, VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
return EFI_SUCCESS;
}
}
Variable = GetNextVariablePtr (Variable);
}
//
// If gone through the VariableStore, that means we never find in Firmware any more.
//
if (IndexTable->Length < VARIABLE_INDEX_TABLE_VOLUME) {
IndexTable->GoneThrough = 1;
}
PtrTrack->CurrPtr = NULL;
return EFI_NOT_FOUND;
}
/**
This service retrieves a variable's value using its name and GUID.
Read the specified variable from the UEFI variable store. If the Data
buffer is too small to hold the contents of the variable, the error
EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
size to obtain the data.
@param This A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
@param VariableName A pointer to a null-terminated string that is the variable's name.
@param VariableGuid A pointer to an EFI_GUID that is the variable's GUID. The combination of
VariableGuid and VariableName must be unique.
@param Attributes If non-NULL, on return, points to the variable's attributes.
@param DataSize On entry, points to the size in bytes of the Data buffer.
On return, points to the size of the data returned in Data.
@param Data Points to the buffer which will hold the returned variable value.
@retval EFI_SUCCESS The variable was read successfully.
@retval EFI_NOT_FOUND The variable could not be found.
@retval EFI_BUFFER_TOO_SMALL The DataSize is too small for the resulting data.
DataSize is updated with the size required for
the specified variable.
@retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
@retval EFI_DEVICE_ERROR The variable could not be retrieved because of a device error.
**/
EFI_STATUS
EFIAPI
PeiGetVariable (
IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
IN CONST CHAR16 *VariableName,
IN CONST EFI_GUID *VariableGuid,
OUT UINT32 *Attributes,
IN OUT UINTN *DataSize,
OUT VOID *Data
)
{
VARIABLE_POINTER_TRACK Variable;
UINTN VarDataSize;
EFI_STATUS Status;
CONST EFI_PEI_SERVICES **PeiServices;
PeiServices = GetPeiServicesTablePointer ();
if (VariableName == NULL || VariableGuid == NULL || DataSize == NULL) {
return EFI_INVALID_PARAMETER;
}
//
// Find existing variable
//
Status = FindVariable (PeiServices, VariableName, VariableGuid, &Variable);
if (Variable.CurrPtr == NULL || Status != EFI_SUCCESS) {
return Status;
}
//
// Get data size
//
VarDataSize = DataSizeOfVariable (Variable.CurrPtr);
if (*DataSize >= VarDataSize) {
if (Data == NULL) {
return EFI_INVALID_PARAMETER;
}
CopyMem (Data, GetVariableDataPtr (Variable.CurrPtr), VarDataSize);
if (Attributes != NULL) {
*Attributes = Variable.CurrPtr->Attributes;
}
*DataSize = VarDataSize;
return EFI_SUCCESS;
} else {
*DataSize = VarDataSize;
return EFI_BUFFER_TOO_SMALL;
}
}
/**
Return the next variable name and GUID.
This function is called multiple times to retrieve the VariableName
and VariableGuid of all variables currently available in the system.
On each call, the previous results are passed into the interface,
and, on return, the interface returns the data for the next
interface. When the entire variable list has been returned,
EFI_NOT_FOUND is returned.
@param This A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
@param VariableNameSize On entry, points to the size of the buffer pointed to by VariableName.
@param VariableName On entry, a pointer to a null-terminated string that is the variable's name.
On return, points to the next variable's null-terminated name string.
@param VariableGuid On entry, a pointer to an UEFI _GUID that is the variable's GUID.
On return, a pointer to the next variable's GUID.
@retval EFI_SUCCESS The variable was read successfully.
@retval EFI_NOT_FOUND The variable could not be found.
@retval EFI_BUFFER_TOO_SMALL The VariableNameSize is too small for the resulting
data. VariableNameSize is updated with the size
required for the specified variable.
@retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
VariableNameSize is NULL.
@retval EFI_DEVICE_ERROR The variable could not be retrieved because of a device error.
**/
EFI_STATUS
EFIAPI
PeiGetNextVariableName (
IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
IN OUT UINTN *VariableNameSize,
IN OUT CHAR16 *VariableName,
IN OUT EFI_GUID *VariableGuid
)
{
VARIABLE_POINTER_TRACK Variable;
UINTN VarNameSize;
EFI_STATUS Status;
CONST EFI_PEI_SERVICES **PeiServices;
PeiServices = GetPeiServicesTablePointer ();
if (VariableName == NULL || VariableGuid == NULL || VariableNameSize == NULL) {
return EFI_INVALID_PARAMETER;
}
Status = FindVariable (PeiServices, VariableName, VariableGuid, &Variable);
if (Variable.CurrPtr == NULL || Status != EFI_SUCCESS) {
return Status;
}
if (VariableName[0] != 0) {
//
// If variable name is not NULL, get next variable
//
Variable.CurrPtr = GetNextVariablePtr (Variable.CurrPtr);
}
while (!(Variable.CurrPtr >= Variable.EndPtr || Variable.CurrPtr == NULL)) {
if (IsValidVariableHeader (Variable.CurrPtr)) {
if (Variable.CurrPtr->State == VAR_ADDED) {
ASSERT (NameSizeOfVariable (Variable.CurrPtr) != 0);
VarNameSize = (UINTN) NameSizeOfVariable (Variable.CurrPtr);
if (VarNameSize <= *VariableNameSize) {
CopyMem (VariableName, GetVariableNamePtr (Variable.CurrPtr), VarNameSize);
CopyMem (VariableGuid, &Variable.CurrPtr->VendorGuid, sizeof (EFI_GUID));
Status = EFI_SUCCESS;
} else {
Status = EFI_BUFFER_TOO_SMALL;
}
*VariableNameSize = VarNameSize;
return Status;
//
// Variable is found
//
} else {
Variable.CurrPtr = GetNextVariablePtr (Variable.CurrPtr);
}
} else {
break;
}
}
return EFI_NOT_FOUND;
}