/**
Get scratch buffer.
@param[in, out] ScratchBufferSize Scratch buffer size. If input size is greater than
the maximum supported buffer size, this value contains
the maximum supported buffer size as output.
@param[out] ScratchBuffer Pointer to scratch buffer address.
@retval EFI_SUCCESS Get scratch buffer successfully.
@retval EFI_UNSUPPORTED If input size is greater than the maximum supported buffer size.
**/
EFI_STATUS
EFIAPI
VariableExLibGetScratchBuffer (
IN OUT UINTN *ScratchBufferSize,
OUT VOID **ScratchBuffer
)
{
UINTN MaxBufferSize;
MaxBufferSize = mVariableModuleGlobal->ScratchBufferSize;
if (*ScratchBufferSize > MaxBufferSize) {
*ScratchBufferSize = MaxBufferSize;
return EFI_UNSUPPORTED;
}
*ScratchBuffer = GetEndPointer ((VARIABLE_STORE_HEADER *) ((UINTN) mVariableModuleGlobal->VariableGlobal.VolatileVariableBase));
return EFI_SUCCESS;
}
/**
Find the variable in the specified variable store.
@param StoreInfo Pointer to the store info structure.
@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
FindVariableEx (
IN VARIABLE_STORE_INFO *StoreInfo,
IN CONST CHAR16 *VariableName,
IN CONST EFI_GUID *VendorGuid,
OUT VARIABLE_POINTER_TRACK *PtrTrack
)
{
VARIABLE_HEADER *Variable;
VARIABLE_HEADER *LastVariable;
VARIABLE_HEADER *MaxIndex;
UINTN Index;
UINTN Offset;
BOOLEAN StopRecord;
VARIABLE_HEADER *InDeletedVariable;
VARIABLE_STORE_HEADER *VariableStoreHeader;
VARIABLE_INDEX_TABLE *IndexTable;
VARIABLE_HEADER *VariableHeader;
VariableStoreHeader = StoreInfo->VariableStoreHeader;
if (VariableStoreHeader == NULL) {
return EFI_INVALID_PARAMETER;
}
if (GetVariableStoreStatus (VariableStoreHeader) != EfiValid) {
return EFI_UNSUPPORTED;
}
if (~VariableStoreHeader->Size == 0) {
return EFI_NOT_FOUND;
}
IndexTable = StoreInfo->IndexTable;
PtrTrack->StartPtr = GetStartPointer (VariableStoreHeader);
PtrTrack->EndPtr = GetEndPointer (VariableStoreHeader);
InDeletedVariable = NULL;
//
// No Variable Address equals zero, so 0 as initial value is safe.
//
MaxIndex = NULL;
VariableHeader = NULL;
if (IndexTable != NULL) {
//
// traverse the variable index table to look for varible.
// The IndexTable->Index[Index] records the distance of two neighbouring VAR_ADDED type variables.
//
for (Offset = 0, Index = 0; Index < IndexTable->Length; Index++) {
ASSERT (Index < sizeof (IndexTable->Index) / sizeof (IndexTable->Index[0]));
Offset += IndexTable->Index[Index];
MaxIndex = (VARIABLE_HEADER *) ((UINT8 *) IndexTable->StartPtr + Offset);
GetVariableHeader (StoreInfo, MaxIndex, &VariableHeader);
if (CompareWithValidVariable (StoreInfo, MaxIndex, VariableHeader, VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
if (VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
InDeletedVariable = PtrTrack->CurrPtr;
} else {
return EFI_SUCCESS;
}
}
}
if (IndexTable->GoneThrough != 0) {
//
// If the table has all the existing variables indexed, return.
//
PtrTrack->CurrPtr = InDeletedVariable;
return (PtrTrack->CurrPtr == NULL) ? EFI_NOT_FOUND : EFI_SUCCESS;
}
}
if (MaxIndex != NULL) {
//
// HOB exists but the variable cannot be found in HOB
// If not found in HOB, then let's start from the MaxIndex we've found.
//
Variable = GetNextVariablePtr (StoreInfo, MaxIndex, VariableHeader);
LastVariable = MaxIndex;
} else {
//
// Start Pointers for the variable.
// Actual Data Pointer where data can be written.
//
Variable = PtrTrack->StartPtr;
LastVariable = PtrTrack->StartPtr;
}
//
// Find the variable by walk through variable store
//
StopRecord = FALSE;
while (GetVariableHeader (StoreInfo, Variable, &VariableHeader)) {
if (VariableHeader->State == VAR_ADDED || VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
//
// Record Variable in VariableIndex HOB
//
if ((IndexTable != NULL) && !StopRecord) {
Offset = (UINTN) Variable - (UINTN) LastVariable;
if ((Offset > 0x0FFFF) || (IndexTable->Length == sizeof (IndexTable->Index) / sizeof (IndexTable->Index[0]))) {
//
// Stop to record if the distance of two neighbouring VAR_ADDED variable is larger than the allowable scope(UINT16),
// or the record buffer is full.
//
StopRecord = TRUE;
} else {
IndexTable->Index[IndexTable->Length++] = (UINT16) Offset;
LastVariable = Variable;
}
}
if (CompareWithValidVariable (StoreInfo, Variable, VariableHeader, VariableName, VendorGuid, PtrTrack) == EFI_SUCCESS) {
if (VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
InDeletedVariable = PtrTrack->CurrPtr;
} else {
return EFI_SUCCESS;
}
}
}
Variable = GetNextVariablePtr (StoreInfo, Variable, VariableHeader);
}
//
// If gone through the VariableStore, that means we never find in Firmware any more.
//
if ((IndexTable != NULL) && !StopRecord) {
IndexTable->GoneThrough = 1;
}
PtrTrack->CurrPtr = InDeletedVariable;
return (PtrTrack->CurrPtr == NULL) ? EFI_NOT_FOUND : EFI_SUCCESS;
}
/**
Get variable header that has consecutive content.
@param StoreInfo Pointer to variable store info structure.
@param Variable Pointer to the Variable Header.
@param VariableHeader Pointer to Pointer to the Variable Header that has consecutive content.
@retval TRUE Variable header is valid.
@retval FALSE Variable header is not valid.
**/
BOOLEAN
GetVariableHeader (
IN VARIABLE_STORE_INFO *StoreInfo,
IN VARIABLE_HEADER *Variable,
OUT VARIABLE_HEADER **VariableHeader
)
{
EFI_PHYSICAL_ADDRESS TargetAddress;
EFI_PHYSICAL_ADDRESS SpareAddress;
EFI_HOB_GUID_TYPE *GuidHob;
UINTN PartialHeaderSize;
if (Variable == NULL) {
return FALSE;
}
//
// First assume variable header pointed by Variable is consecutive.
//
*VariableHeader = Variable;
if (StoreInfo->FtwLastWriteData != NULL) {
TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;
SpareAddress = StoreInfo->FtwLastWriteData->SpareAddress;
if (((UINTN) Variable > (UINTN) SpareAddress) &&
(((UINTN) Variable - (UINTN) SpareAddress + (UINTN) TargetAddress) >= (UINTN) GetEndPointer (StoreInfo->VariableStoreHeader))) {
//
// Reach the end of variable store.
//
return FALSE;
}
if (((UINTN) Variable < (UINTN) TargetAddress) && (((UINTN) Variable + GetVariableHeaderSize (StoreInfo->AuthFlag)) > (UINTN) TargetAddress)) {
//
// Variable header pointed by Variable is inconsecutive,
// create a guid hob to combine the two partial variable header content together.
//
GuidHob = GetFirstGuidHob (&gEfiCallerIdGuid);
if (GuidHob != NULL) {
*VariableHeader = (VARIABLE_HEADER *) GET_GUID_HOB_DATA (GuidHob);
} else {
*VariableHeader = (VARIABLE_HEADER *) BuildGuidHob (&gEfiCallerIdGuid, GetVariableHeaderSize (StoreInfo->AuthFlag));
PartialHeaderSize = (UINTN) TargetAddress - (UINTN) Variable;
//
// Partial content is in NV storage.
//
CopyMem ((UINT8 *) *VariableHeader, (UINT8 *) Variable, PartialHeaderSize);
//
// Another partial content is in spare block.
//
CopyMem ((UINT8 *) *VariableHeader + PartialHeaderSize, (UINT8 *) (UINTN) SpareAddress, GetVariableHeaderSize (StoreInfo->AuthFlag) - PartialHeaderSize);
}
}
} else {
if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {
//
// Reach the end of variable store.
//
return FALSE;
}
}
return IsValidVariableHeader (*VariableHeader);
}
/**
Return the variable store header and the store info based on the Index.
@param Type The type of the variable store.
@param StoreInfo Return the store info.
@return Pointer to the variable store header.
**/
VARIABLE_STORE_HEADER *
GetVariableStore (
IN VARIABLE_STORE_TYPE Type,
OUT VARIABLE_STORE_INFO *StoreInfo
)
{
EFI_HOB_GUID_TYPE *GuidHob;
EFI_FIRMWARE_VOLUME_HEADER *FvHeader;
VARIABLE_STORE_HEADER *VariableStoreHeader;
EFI_PHYSICAL_ADDRESS NvStorageBase;
UINT32 NvStorageSize;
FAULT_TOLERANT_WRITE_LAST_WRITE_DATA *FtwLastWriteData;
UINT32 BackUpOffset;
StoreInfo->IndexTable = NULL;
StoreInfo->FtwLastWriteData = NULL;
StoreInfo->AuthFlag = FALSE;
VariableStoreHeader = NULL;
switch (Type) {
case VariableStoreTypeHob:
GuidHob = GetFirstGuidHob (&gEfiAuthenticatedVariableGuid);
if (GuidHob != NULL) {
VariableStoreHeader = (VARIABLE_STORE_HEADER *) GET_GUID_HOB_DATA (GuidHob);
StoreInfo->AuthFlag = TRUE;
} else {
GuidHob = GetFirstGuidHob (&gEfiVariableGuid);
if (GuidHob != NULL) {
VariableStoreHeader = (VARIABLE_STORE_HEADER *) GET_GUID_HOB_DATA (GuidHob);
StoreInfo->AuthFlag = FALSE;
}
}
break;
case VariableStoreTypeNv:
if (GetBootModeHob () != BOOT_IN_RECOVERY_MODE) {
//
// The content of NV storage for variable is not reliable in recovery boot mode.
//
NvStorageSize = PcdGet32 (PcdFlashNvStorageVariableSize);
NvStorageBase = (EFI_PHYSICAL_ADDRESS) (PcdGet64 (PcdFlashNvStorageVariableBase64) != 0 ?
PcdGet64 (PcdFlashNvStorageVariableBase64) :
PcdGet32 (PcdFlashNvStorageVariableBase)
);
//
// First let FvHeader point to NV storage base.
//
FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *) (UINTN) NvStorageBase;
//
// Check the FTW last write data hob.
//
BackUpOffset = 0;
GuidHob = GetFirstGuidHob (&gEdkiiFaultTolerantWriteGuid);
if (GuidHob != NULL) {
FtwLastWriteData = (FAULT_TOLERANT_WRITE_LAST_WRITE_DATA *) GET_GUID_HOB_DATA (GuidHob);
if (FtwLastWriteData->TargetAddress == NvStorageBase) {
//
// Let FvHeader point to spare block.
//
FvHeader = (EFI_FIRMWARE_VOLUME_HEADER *) (UINTN) FtwLastWriteData->SpareAddress;
DEBUG ((EFI_D_INFO, "PeiVariable: NV storage is backed up in spare block: 0x%x\n", (UINTN) FtwLastWriteData->SpareAddress));
} else if ((FtwLastWriteData->TargetAddress > NvStorageBase) && (FtwLastWriteData->TargetAddress < (NvStorageBase + NvStorageSize))) {
StoreInfo->FtwLastWriteData = FtwLastWriteData;
//
// Flash NV storage from the offset is backed up in spare block.
//
BackUpOffset = (UINT32) (FtwLastWriteData->TargetAddress - NvStorageBase);
DEBUG ((EFI_D_INFO, "PeiVariable: High partial NV storage from offset: %x is backed up in spare block: 0x%x\n", BackUpOffset, (UINTN) FtwLastWriteData->SpareAddress));
//
// At least one block data in flash NV storage is still valid, so still leave FvHeader point to NV storage base.
//
}
}
//
// Check if the Firmware Volume is not corrupted
//
if ((FvHeader->Signature != EFI_FVH_SIGNATURE) || (!CompareGuid (&gEfiSystemNvDataFvGuid, &FvHeader->FileSystemGuid))) {
DEBUG ((EFI_D_ERROR, "Firmware Volume for Variable Store is corrupted\n"));
break;
}
VariableStoreHeader = (VARIABLE_STORE_HEADER *) ((UINT8 *) FvHeader + FvHeader->HeaderLength);
StoreInfo->AuthFlag = (BOOLEAN) (CompareGuid (&VariableStoreHeader->Signature, &gEfiAuthenticatedVariableGuid));
GuidHob = GetFirstGuidHob (&gEfiVariableIndexTableGuid);
if (GuidHob != NULL) {
StoreInfo->IndexTable = GET_GUID_HOB_DATA (GuidHob);
} else {
//
// If it's the first time to access variable region in flash, create a guid hob to record
// VAR_ADDED type variable info.
// Note that as the resource of PEI phase is limited, only store the limited number of
// VAR_ADDED type variables to reduce access time.
//
StoreInfo->IndexTable = (VARIABLE_INDEX_TABLE *) BuildGuidHob (&gEfiVariableIndexTableGuid, sizeof (VARIABLE_INDEX_TABLE));
StoreInfo->IndexTable->Length = 0;
StoreInfo->IndexTable->StartPtr = GetStartPointer (VariableStoreHeader);
StoreInfo->IndexTable->EndPtr = GetEndPointer (VariableStoreHeader);
StoreInfo->IndexTable->GoneThrough = 0;
}
}
break;
default:
ASSERT (FALSE);
break;
}
StoreInfo->VariableStoreHeader = VariableStoreHeader;
return VariableStoreHeader;
}
/**
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.
On return, the size of the variable name buffer.
@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 EFI_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_STORE_TYPE Type;
VARIABLE_POINTER_TRACK Variable;
VARIABLE_POINTER_TRACK VariableInHob;
VARIABLE_POINTER_TRACK VariablePtrTrack;
UINTN VarNameSize;
EFI_STATUS Status;
VARIABLE_STORE_HEADER *VariableStoreHeader[VariableStoreTypeMax];
VARIABLE_HEADER *VariableHeader;
VARIABLE_STORE_INFO StoreInfo;
VARIABLE_STORE_INFO StoreInfoForNv;
VARIABLE_STORE_INFO StoreInfoForHob;
if (VariableName == NULL || VariableGuid == NULL || VariableNameSize == NULL) {
return EFI_INVALID_PARAMETER;
}
VariableHeader = NULL;
Status = FindVariable (VariableName, VariableGuid, &Variable, &StoreInfo);
if (Variable.CurrPtr == NULL || Status != EFI_SUCCESS) {
return Status;
}
if (VariableName[0] != 0) {
//
// If variable name is not NULL, get next variable
//
GetVariableHeader (&StoreInfo, Variable.CurrPtr, &VariableHeader);
Variable.CurrPtr = GetNextVariablePtr (&StoreInfo, Variable.CurrPtr, VariableHeader);
}
VariableStoreHeader[VariableStoreTypeHob] = GetVariableStore (VariableStoreTypeHob, &StoreInfoForHob);
VariableStoreHeader[VariableStoreTypeNv] = GetVariableStore (VariableStoreTypeNv, &StoreInfoForNv);
while (TRUE) {
//
// Switch from HOB to Non-Volatile.
//
while (!GetVariableHeader (&StoreInfo, Variable.CurrPtr, &VariableHeader)) {
//
// Find current storage index
//
for (Type = (VARIABLE_STORE_TYPE) 0; Type < VariableStoreTypeMax; Type++) {
if ((VariableStoreHeader[Type] != NULL) && (Variable.StartPtr == GetStartPointer (VariableStoreHeader[Type]))) {
break;
}
}
ASSERT (Type < VariableStoreTypeMax);
//
// Switch to next storage
//
for (Type++; Type < VariableStoreTypeMax; Type++) {
if (VariableStoreHeader[Type] != NULL) {
break;
}
}
//
// Capture the case that
// 1. current storage is the last one, or
// 2. no further storage
//
if (Type == VariableStoreTypeMax) {
return EFI_NOT_FOUND;
}
Variable.StartPtr = GetStartPointer (VariableStoreHeader[Type]);
Variable.EndPtr = GetEndPointer (VariableStoreHeader[Type]);
Variable.CurrPtr = Variable.StartPtr;
GetVariableStore (Type, &StoreInfo);
}
if (VariableHeader->State == VAR_ADDED || VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
if (VariableHeader->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {
//
// If it is a IN_DELETED_TRANSITION variable,
// and there is also a same ADDED one at the same time,
// don't return it.
//
Status = FindVariableEx (
&StoreInfo,
GetVariableNamePtr (Variable.CurrPtr, StoreInfo.AuthFlag),
GetVendorGuidPtr (VariableHeader, StoreInfo.AuthFlag),
&VariablePtrTrack
);
if (!EFI_ERROR (Status) && VariablePtrTrack.CurrPtr != Variable.CurrPtr) {
Variable.CurrPtr = GetNextVariablePtr (&StoreInfo, Variable.CurrPtr, VariableHeader);
continue;
}
}
//
// Don't return NV variable when HOB overrides it
//
if ((VariableStoreHeader[VariableStoreTypeHob] != NULL) && (VariableStoreHeader[VariableStoreTypeNv] != NULL) &&
(Variable.StartPtr == GetStartPointer (VariableStoreHeader[VariableStoreTypeNv]))
) {
Status = FindVariableEx (
&StoreInfoForHob,
GetVariableNamePtr (Variable.CurrPtr, StoreInfo.AuthFlag),
GetVendorGuidPtr (VariableHeader, StoreInfo.AuthFlag),
&VariableInHob
);
if (!EFI_ERROR (Status)) {
Variable.CurrPtr = GetNextVariablePtr (&StoreInfo, Variable.CurrPtr, VariableHeader);
continue;
}
}
VarNameSize = NameSizeOfVariable (VariableHeader, StoreInfo.AuthFlag);
ASSERT (VarNameSize != 0);
if (VarNameSize <= *VariableNameSize) {
GetVariableNameOrData (&StoreInfo, (UINT8 *) GetVariableNamePtr (Variable.CurrPtr, StoreInfo.AuthFlag), VarNameSize, (UINT8 *) VariableName);
CopyMem (VariableGuid, GetVendorGuidPtr (VariableHeader, StoreInfo.AuthFlag), sizeof (EFI_GUID));
Status = EFI_SUCCESS;
} else {
Status = EFI_BUFFER_TOO_SMALL;
}
*VariableNameSize = VarNameSize;
//
// Variable is found
//
return Status;
} else {
Variable.CurrPtr = GetNextVariablePtr (&StoreInfo, Variable.CurrPtr, VariableHeader);
}
}
}
