#include "Variable.h"

Functions
EFI_STATUS EFIAPI	BuildVariableRuntimeCacheInfoHob (IN EFI_PEI_SERVICES *PeiServices, IN EFI_PEI_NOTIFY_DESCRIPTOR NotifyDescriptor, IN VOID *Ppi)

EFI_STATUS EFIAPI	PeimInitializeVariableServices (IN EFI_PEI_FILE_HANDLE FileHandle, IN CONST EFI_PEI_SERVICES **PeiServices)

VARIABLE_HEADER *	GetStartPointer (IN VARIABLE_STORE_HEADER *VarStoreHeader)

VARIABLE_HEADER *	GetEndPointer (IN VARIABLE_STORE_HEADER *VarStoreHeader)

BOOLEAN	IsValidVariableHeader (IN VARIABLE_HEADER *Variable)

UINTN	GetVariableHeaderSize (IN BOOLEAN AuthFlag)

UINTN	NameSizeOfVariable (IN VARIABLE_HEADER *Variable, IN BOOLEAN AuthFlag)

UINTN	DataSizeOfVariable (IN VARIABLE_HEADER *Variable, IN BOOLEAN AuthFlag)

CHAR16 *	GetVariableNamePtr (IN VARIABLE_HEADER *Variable, IN BOOLEAN AuthFlag)

EFI_GUID *	GetVendorGuidPtr (IN VARIABLE_HEADER *Variable, IN BOOLEAN AuthFlag)

UINT8 *	GetVariableDataPtr (IN VARIABLE_HEADER Variable, IN VARIABLE_HEADER VariableHeader, IN BOOLEAN AuthFlag)

VARIABLE_HEADER *	GetNextVariablePtr (IN VARIABLE_STORE_INFO StoreInfo, IN VARIABLE_HEADER Variable, IN VARIABLE_HEADER *VariableHeader)

VARIABLE_STORE_STATUS	GetVariableStoreStatus (IN VARIABLE_STORE_HEADER *VarStoreHeader)

BOOLEAN	CompareVariableName (IN VARIABLE_STORE_INFO StoreInfo, IN CONST CHAR16 Name1, IN CONST CHAR16 *Name2, IN UINTN NameSize)

EFI_STATUS	CompareWithValidVariable (IN VARIABLE_STORE_INFO StoreInfo, IN VARIABLE_HEADER Variable, IN VARIABLE_HEADER VariableHeader, IN CONST CHAR16 VariableName, IN CONST EFI_GUID VendorGuid, OUT VARIABLE_POINTER_TRACK PtrTrack)

VOID	GetHobVariableStore (OUT VARIABLE_STORE_INFO StoreInfo, OUT VARIABLE_STORE_HEADER *VariableStoreHeader)

VARIABLE_STORE_HEADER *	GetVariableStore (IN VARIABLE_STORE_TYPE Type, OUT VARIABLE_STORE_INFO *StoreInfo)

BOOLEAN	GetVariableHeader (IN VARIABLE_STORE_INFO StoreInfo, IN VARIABLE_HEADER Variable, OUT VARIABLE_HEADER **VariableHeader)

VOID	GetVariableNameOrData (IN VARIABLE_STORE_INFO StoreInfo, IN UINT8 NameOrData, IN UINTN Size, OUT UINT8 *Buffer)

EFI_STATUS	FindVariableEx (IN VARIABLE_STORE_INFO StoreInfo, IN CONST CHAR16 VariableName, IN CONST EFI_GUID VendorGuid, OUT VARIABLE_POINTER_TRACK PtrTrack)

EFI_STATUS	FindVariable (IN CONST CHAR16 VariableName, IN CONST EFI_GUID VendorGuid, OUT VARIABLE_POINTER_TRACK PtrTrack, OUT VARIABLE_STORE_INFO StoreInfo)

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 OPTIONAL)

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)

UINTN	CalculateAuthVarStorageSize (IN VARIABLE_STORE_INFO StoreInfo, IN VARIABLE_STORE_HEADER NormalHobVarStorage)

UINTN	CalculateHobVariableCacheSize (IN BOOLEAN NvAuthFlag)

UINTN	CalculateNvVariableCacheSize (OUT BOOLEAN *NvAuthFlag)

Variables
EFI_PEI_READ_ONLY_VARIABLE2_PPI	mVariablePpi

EFI_PEI_PPI_DESCRIPTOR	mPpiListVariable

EFI_PEI_NOTIFY_DESCRIPTOR	mPostMemNotifyList

Detailed Description

Implement ReadOnly Variable Services required by PEIM and install PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.

Copyright (c) 2006 - 2024, Intel Corporation. All rights reserved.
Copyright (c) Microsoft Corporation.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file Variable.c.

Function Documentation

◆ BuildVariableRuntimeCacheInfoHob()

EFI_STATUS EFIAPI BuildVariableRuntimeCacheInfoHob	(	IN EFI_PEI_SERVICES **	PeiServices,
		IN EFI_PEI_NOTIFY_DESCRIPTOR *	NotifyDescriptor,
		IN VOID *	Ppi
	)

Build gEdkiiVariableRuntimeCacheInfoHobGuid.

Parameters

[in]	PeiServices	General purpose services available to every PEIM.
[in]	NotifyDescriptor	The notification structure this PEIM registered on install.
[in]	Ppi	The memory discovered PPI. Not used.

Return values

EFI_SUCCESS	The function completed successfully.
others	Failed to build VariableRuntimeCacheInfo Hob.

Definition at line 1428 of file Variable.c.

◆ CalculateAuthVarStorageSize()

UINTN CalculateAuthVarStorageSize	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN VARIABLE_STORE_HEADER *	NormalHobVarStorage
	)

Calculate the auth variable storage size converted from normal variable storage.

Parameters

[in]	StoreInfo	Pointer to the store info
[in]	NormalHobVarStorage	Pointer to the normal variable storage header

Return values

the	auth variable storage size

Definition at line 1292 of file Variable.c.

◆ CalculateHobVariableCacheSize()

UINTN CalculateHobVariableCacheSize ( IN BOOLEAN NvAuthFlag )

Calculate Hob variable cache size.

Parameters

[in] NvAuthFlag If the NV variable store is Auth.

Return values

Maximum of Nv variable cache size.

Definition at line 1331 of file Variable.c.

◆ CalculateNvVariableCacheSize()

UINTN CalculateNvVariableCacheSize ( OUT BOOLEAN * NvAuthFlag )

Calculate Nv variable cache size.

Parameters

[out] NvAuthFlag If the NV variable store is Auth.

Return values

Maximum of Nv variable cache size.

Definition at line 1370 of file Variable.c.

◆ CompareVariableName()

BOOLEAN CompareVariableName	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN CONST CHAR16 *	Name1,
		IN CONST CHAR16 *	Name2,
		IN UINTN	NameSize
	)

Compare two variable names, one of them may be inconsecutive.

Parameters

StoreInfo	Pointer to variable store info structure.
Name1	Pointer to one variable name.
Name2	Pointer to another variable name.
NameSize	Variable name size.

Return values

TRUE	Name1 and Name2 are identical.
FALSE	Name1 and Name2 are not identical.

Definition at line 413 of file Variable.c.

◆ CompareWithValidVariable()

EFI_STATUS CompareWithValidVariable	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN VARIABLE_HEADER *	Variable,
		IN VARIABLE_HEADER *	VariableHeader,
		IN CONST CHAR16 *	VariableName,
		IN CONST EFI_GUID *	VendorGuid,
		OUT VARIABLE_POINTER_TRACK *	PtrTrack
	)

This function compares a variable with variable entries in database.

Parameters

StoreInfo	Pointer to variable store info structure.
Variable	Pointer to the variable in our database
VariableHeader	Pointer to the Variable Header that has consecutive content.
VariableName	Name of the variable to compare to 'Variable'
VendorGuid	GUID of the variable to compare to 'Variable'
PtrTrack	Variable Track Pointer structure that contains Variable Information.

Return values

EFI_SUCCESS	Found match variable
EFI_NOT_FOUND	Variable not found

Definition at line 491 of file Variable.c.

◆ DataSizeOfVariable()

UINTN DataSizeOfVariable	(	IN VARIABLE_HEADER *	Variable,
		IN BOOLEAN	AuthFlag
	)

This code gets the size of data of variable.

Parameters

Variable	Pointer to the Variable Header.
AuthFlag	Authenticated variable flag.

Returns: Size of variable in bytes in type UINTN.

Definition at line 215 of file Variable.c.

◆ FindVariable()

EFI_STATUS FindVariable	(	IN CONST CHAR16 *	VariableName,
		IN CONST EFI_GUID *	VendorGuid,
		OUT VARIABLE_POINTER_TRACK *	PtrTrack,
		OUT VARIABLE_STORE_INFO *	StoreInfo
	)

Find the variable in HOB and Non-Volatile variable storages.

Parameters

VariableName	Name of the variable to be found
VendorGuid	Vendor GUID to be found.
PtrTrack	Variable Track Pointer structure that contains Variable Information.
StoreInfo	Return the store info.

Return values

EFI_SUCCESS	Variable found successfully
EFI_NOT_FOUND	Variable not found
EFI_INVALID_PARAMETER	Invalid variable name

Definition at line 992 of file Variable.c.

◆ FindVariableEx()

EFI_STATUS FindVariableEx	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN CONST CHAR16 *	VariableName,
		IN CONST EFI_GUID *	VendorGuid,
		OUT VARIABLE_POINTER_TRACK *	PtrTrack
	)

Find the variable in the specified variable store.

Parameters

StoreInfo	Pointer to the store info structure.
VariableName	Name of the variable to be found
VendorGuid	Vendor GUID to be found.
PtrTrack	Variable Track Pointer structure that contains Variable Information.

Return values

EFI_SUCCESS	Variable found successfully
EFI_NOT_FOUND	Variable not found
EFI_INVALID_PARAMETER	Invalid variable name

Definition at line 844 of file Variable.c.

◆ GetEndPointer()

VARIABLE_HEADER * GetEndPointer ( IN VARIABLE_STORE_HEADER * VarStoreHeader )

Gets the pointer to the end of the variable storage area.

This function gets pointer to the end of the variable storage area, according to the input variable store header.

Parameters

VarStoreHeader Pointer to the Variable Store Header.

Returns: Pointer to the end of the variable storage area.

Definition at line 109 of file Variable.c.

◆ GetHobVariableStore()

VOID GetHobVariableStore	(	OUT VARIABLE_STORE_INFO *	StoreInfo,
		OUT VARIABLE_STORE_HEADER **	VariableStoreHeader
	)

Get HOB variable store.

Parameters

[out]	StoreInfo	Return the store info.
[out]	VariableStoreHeader	Return variable store header.

Definition at line 540 of file Variable.c.

◆ GetNextVariablePtr()

VARIABLE_HEADER * GetNextVariablePtr	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN VARIABLE_HEADER *	Variable,
		IN VARIABLE_HEADER *	VariableHeader
	)

This code gets the pointer to the next variable header.

Parameters

StoreInfo	Pointer to variable store info structure.
Variable	Pointer to the Variable Header.
VariableHeader	Pointer to the Variable Header that has consecutive content.

Returns: A VARIABLE_HEADER* pointer to next variable header.

Definition at line 329 of file Variable.c.

◆ GetStartPointer()

VARIABLE_HEADER * GetStartPointer ( IN VARIABLE_STORE_HEADER * VarStoreHeader )

Gets the pointer to the first variable header in given variable store area.

Parameters

VarStoreHeader Pointer to the Variable Store Header.

Returns: Pointer to the first variable header.

Definition at line 86 of file Variable.c.

◆ GetVariableDataPtr()

UINT8 * GetVariableDataPtr	(	IN VARIABLE_HEADER *	Variable,
		IN VARIABLE_HEADER *	VariableHeader,
		IN BOOLEAN	AuthFlag
	)

This code gets the pointer to the variable data.

Parameters

Variable	Pointer to the Variable Header.
VariableHeader	Pointer to the Variable Header that has consecutive content.
AuthFlag	Authenticated variable flag.

Returns: A UINT8* pointer to Variable Data.

Definition at line 300 of file Variable.c.

◆ GetVariableHeader()

BOOLEAN GetVariableHeader	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN VARIABLE_HEADER *	Variable,
		OUT VARIABLE_HEADER **	VariableHeader
	)

Get variable header that has consecutive content.

Parameters

StoreInfo	Pointer to variable store info structure.
Variable	Pointer to the Variable Header.
VariableHeader	Pointer to Pointer to the Variable Header that has consecutive content.

Return values

TRUE	Variable header is valid.
FALSE	Variable header is not valid.

Definition at line 718 of file Variable.c.

◆ GetVariableHeaderSize()

UINTN GetVariableHeaderSize ( IN BOOLEAN AuthFlag )

This code gets the size of variable header.

Parameters

AuthFlag Authenticated variable flag.

Returns: Size of variable header in bytes in type UINTN.

Definition at line 149 of file Variable.c.

◆ GetVariableNameOrData()

VOID GetVariableNameOrData	(	IN VARIABLE_STORE_INFO *	StoreInfo,
		IN UINT8 *	NameOrData,
		IN UINTN	Size,
		OUT UINT8 *	Buffer
	)

Get variable name or data to output buffer.

Parameters

StoreInfo	Pointer to variable store info structure.
NameOrData	Pointer to the variable name/data that may be inconsecutive.
Size	Variable name/data size.
Buffer	Pointer to output buffer to hold the variable name/data.

Definition at line 793 of file Variable.c.

◆ GetVariableNamePtr()

CHAR16 * GetVariableNamePtr	(	IN VARIABLE_HEADER *	Variable,
		IN BOOLEAN	AuthFlag
	)

This code gets the pointer to the variable name.

Parameters

Variable	Pointer to the Variable Header.
AuthFlag	Authenticated variable flag.

Returns: A CHAR16* pointer to Variable Name.

Definition at line 256 of file Variable.c.

◆ GetVariableStore()

VARIABLE_STORE_HEADER * GetVariableStore	(	IN VARIABLE_STORE_TYPE	Type,
		OUT VARIABLE_STORE_INFO *	StoreInfo
	)

Return the variable store header and the store info based on the Index.

Parameters

Type	The type of the variable store.
StoreInfo	Return the store info.

Returns: Pointer to the variable store header.

Definition at line 594 of file Variable.c.

◆ GetVariableStoreStatus()

VARIABLE_STORE_STATUS GetVariableStoreStatus ( IN VARIABLE_STORE_HEADER * VarStoreHeader )

Get variable store status.

Parameters

VarStoreHeader Pointer to the Variable Store Header.

Return values

EfiRaw	Variable store is raw
EfiValid	Variable store is valid
EfiInvalid	Variable store is invalid

Definition at line 372 of file Variable.c.

◆ GetVendorGuidPtr()

EFI_GUID * GetVendorGuidPtr	(	IN VARIABLE_HEADER *	Variable,
		IN BOOLEAN	AuthFlag
	)

This code gets the pointer to the variable guid.

Parameters

Variable	Pointer to the Variable Header.
AuthFlag	Authenticated variable flag.

Returns: A EFI_GUID* pointer to Vendor Guid.

Definition at line 274 of file Variable.c.

◆ IsValidVariableHeader()

BOOLEAN IsValidVariableHeader ( IN VARIABLE_HEADER * Variable )

This code checks if variable header is valid or not.

Parameters

Variable Pointer to the Variable Header.

Return values

TRUE	Variable header is valid.
FALSE	Variable header is not valid.

Definition at line 129 of file Variable.c.

◆ NameSizeOfVariable()

UINTN NameSizeOfVariable	(	IN VARIABLE_HEADER *	Variable,
		IN BOOLEAN	AuthFlag
	)

This code gets the size of name of variable.

Parameters

Variable	Pointer to the Variable Header.
AuthFlag	Authenticated variable flag.

Returns: Size of variable in bytes in type UINTN.

Definition at line 174 of file Variable.c.

◆ PeiGetNextVariableName()

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
	)

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.

Parameters

This	A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
VariableNameSize	On entry, points to the size of the buffer pointed to by VariableName. On return, the size of the variable name buffer.
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.
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.

Return values

EFI_SUCCESS	The variable was read successfully.
EFI_NOT_FOUND	The variable could not be found.
EFI_BUFFER_TOO_SMALL	The VariableNameSize is too small for the resulting data. VariableNameSize is updated with the size required for the specified variable.
EFI_INVALID_PARAMETER	VariableName, VariableGuid or VariableNameSize is NULL.
EFI_DEVICE_ERROR	The variable could not be retrieved because of a device error.

Definition at line 1141 of file Variable.c.

◆ PeiGetVariable()

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	OPTIONAL
	)

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.

Parameters

This	A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
VariableName	A pointer to a null-terminated string that is the variable's name.
VariableGuid	A pointer to an EFI_GUID that is the variable's GUID. The combination of VariableGuid and VariableName must be unique.
Attributes	If non-NULL, on return, points to the variable's attributes.
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.
Data	Points to the buffer which will hold the returned variable value. May be NULL with a zero DataSize in order to determine the size of the buffer needed.

Return values

EFI_SUCCESS	The variable was read successfully.
EFI_NOT_FOUND	The variable was be found.
EFI_BUFFER_TOO_SMALL	The DataSize is too small for the resulting data. DataSize is updated with the size required for the specified variable.
EFI_INVALID_PARAMETER	VariableName, VariableGuid, DataSize or Data is NULL.
EFI_DEVICE_ERROR	The variable could not be retrieved because of a device error.

Definition at line 1051 of file Variable.c.

◆ PeimInitializeVariableServices()

EFI_STATUS EFIAPI PeimInitializeVariableServices	(	IN EFI_PEI_FILE_HANDLE	FileHandle,
		IN CONST EFI_PEI_SERVICES **	PeiServices
	)

Provide the functionality of the variable services.

Parameters

FileHandle	Handle of the file being invoked. Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
PeiServices	General purpose services available to every PEIM.

Return values

EFI_SUCCESS	If the interface could be successfully installed
Others	Returned from PeiServicesInstallPpi()

Definition at line 64 of file Variable.c.

Variable Documentation

◆ mPostMemNotifyList

EFI_PEI_NOTIFY_DESCRIPTOR mPostMemNotifyList

Initial value:

= {
  (EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  &gEfiPeiMemoryDiscoveredPpiGuid,
  BuildVariableRuntimeCacheInfoHob
}

Definition at line 46 of file Variable.c.

◆ mPpiListVariable

EFI_PEI_PPI_DESCRIPTOR mPpiListVariable

Initial value:

= {
  (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  &gEfiPeiReadOnlyVariable2PpiGuid,
  &mVariablePpi
}

Definition at line 21 of file Variable.c.

◆ mVariablePpi

EFI_PEI_READ_ONLY_VARIABLE2_PPI mVariablePpi

Initial value:

= {
  PeiGetVariable,
  PeiGetNextVariableName
}

Definition at line 16 of file Variable.c.

Functions

Variables

Detailed Description

Function Documentation

◆ BuildVariableRuntimeCacheInfoHob()

◆ CalculateAuthVarStorageSize()

◆ CalculateHobVariableCacheSize()

◆ CalculateNvVariableCacheSize()

◆ CompareVariableName()

◆ CompareWithValidVariable()

◆ DataSizeOfVariable()

◆ FindVariable()

◆ FindVariableEx()

◆ GetEndPointer()

◆ GetHobVariableStore()

◆ GetNextVariablePtr()

◆ GetStartPointer()

◆ GetVariableDataPtr()

◆ GetVariableHeader()

◆ GetVariableHeaderSize()

◆ GetVariableNameOrData()

◆ GetVariableNamePtr()

◆ GetVariableStore()

◆ GetVariableStoreStatus()

◆ GetVendorGuidPtr()

◆ IsValidVariableHeader()

◆ NameSizeOfVariable()

◆ PeiGetNextVariableName()

◆ PeiGetVariable()

◆ PeimInitializeVariableServices()

Variable Documentation

◆ mPostMemNotifyList

◆ mPpiListVariable

◆ mVariablePpi