MdeModulePkg/Universal/Variable/Pei/Variable.h

   1 /** @file
   2   The internal header file includes the common header files, defines
   3   internal structure and functions used by PeiVariable module.
   4
   5 Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
   6 This program and the accompanying materials
   7 are licensed and made available under the terms and conditions of the BSD License
   8 which accompanies this distribution.  The full text of the license may be found at
   9 http://opensource.org/licenses/bsd-license.php
  10
  11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #ifndef _PEI_VARIABLE_H_
  17 #define _PEI_VARIABLE_H_
  18
  19 #include <PiPei.h>
  20 #include <Ppi/ReadOnlyVariable2.h>
  21
  22 #include <Library/DebugLib.h>
  23 #include <Library/PeimEntryPoint.h>
  24 #include <Library/HobLib.h>
  25 #include <Library/PcdLib.h>
  26 #include <Library/BaseMemoryLib.h>
  27 #include <Library/PeiServicesTablePointerLib.h>
  28 #include <Library/PeiServicesLib.h>
  29
  30 #include <Guid/VariableFormat.h>
  31 #include <Guid/VariableIndexTable.h>
  32 #include <Guid/SystemNvDataGuid.h>
  33 #include <Guid/FaultTolerantWrite.h>
  34
  35 typedef enum {
  36   VariableStoreTypeHob,
  37   VariableStoreTypeNv,
  38   VariableStoreTypeMax
  39 } VARIABLE_STORE_TYPE;
  40
  41 typedef struct {
  42   VARIABLE_STORE_HEADER                   *VariableStoreHeader;
  43   VARIABLE_INDEX_TABLE                    *IndexTable;
  44   //
  45   // If it is not NULL, it means there may be an inconsecutive variable whose
  46   // partial content is still in NV storage, but another partial content is backed up
  47   // in spare block.
  48   //
  49   FAULT_TOLERANT_WRITE_LAST_WRITE_DATA    *FtwLastWriteData;
  50   BOOLEAN                                 AuthFlag;
  51 } VARIABLE_STORE_INFO;
  52
  53 //
  54 // Functions
  55 //
  56 /**
  57   Provide the functionality of the variable services.
  58
  59   @param  FileHandle  Handle of the file being invoked.
  60                       Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
  61   @param  PeiServices  General purpose services available to every PEIM.
  62
  63   @retval EFI_SUCCESS  If the interface could be successfully installed
  64   @retval Others       Returned from PeiServicesInstallPpi()
  65
  66 **/
  67 EFI_STATUS
  68 EFIAPI
  69 PeimInitializeVariableServices (
  70   IN       EFI_PEI_FILE_HANDLE       FileHandle,
  71   IN CONST EFI_PEI_SERVICES          **PeiServices
  72   );
  73
  74 /**
  75   This service retrieves a variable's value using its name and GUID.
  76
  77   Read the specified variable from the UEFI variable store. If the Data
  78   buffer is too small to hold the contents of the variable, the error
  79   EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
  80   size to obtain the data.
  81
  82   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  83   @param  VariableName          A pointer to a null-terminated string that is the variable's name.
  84   @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
  85                                 VariableGuid and VariableName must be unique.
  86   @param  Attributes            If non-NULL, on return, points to the variable's attributes.
  87   @param  DataSize              On entry, points to the size in bytes of the Data buffer.
  88                                 On return, points to the size of the data returned in Data.
  89   @param  Data                  Points to the buffer which will hold the returned variable value.
  90                                 May be NULL with a zero DataSize in order to determine the size of the buffer needed.
  91
  92   @retval EFI_SUCCESS           The variable was read successfully.
  93   @retval EFI_NOT_FOUND         The variable was not found.
  94   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
  95                                 DataSize is updated with the size required for
  96                                 the specified variable.
  97   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
  98   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
  99
 100 **/
 101 EFI_STATUS
 102 EFIAPI
 103 PeiGetVariable (
 104   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 105   IN CONST  CHAR16                          *VariableName,
 106   IN CONST  EFI_GUID                        *VariableGuid,
 107   OUT       UINT32                          *Attributes,
 108   IN OUT    UINTN                           *DataSize,
 109   OUT       VOID                            *Data OPTIONAL
 110   );
 111
 112 /**
 113   Return the next variable name and GUID.
 114
 115   This function is called multiple times to retrieve the VariableName
 116   and VariableGuid of all variables currently available in the system.
 117   On each call, the previous results are passed into the interface,
 118   and, on return, the interface returns the data for the next
 119   interface. When the entire variable list has been returned,
 120   EFI_NOT_FOUND is returned.
 121
 122   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
 123
 124   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
 125   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
 126                             On return, points to the next variable's null-terminated name string.
 127
 128   @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
 129                             On return, a pointer to the next variable's GUID.
 130
 131   @retval EFI_SUCCESS           The variable was read successfully.
 132   @retval EFI_NOT_FOUND         The variable could not be found.
 133   @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
 134                                 data. VariableNameSize is updated with the size
 135                                 required for the specified variable.
 136   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
 137                                 VariableNameSize is NULL.
 138   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 139
 140 **/
 141 EFI_STATUS
 142 EFIAPI
 143 PeiGetNextVariableName (
 144   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 145   IN OUT UINTN                              *VariableNameSize,
 146   IN OUT CHAR16                             *VariableName,
 147   IN OUT EFI_GUID                           *VariableGuid
 148   );
 149
 150 #endif