MdeModulePkg/Universal/Variable/Pei/Variable.h

   1 /** @file
   2
   3   The internal header file includes the common header files, defines
   4   internal structure and functions used by PeiVariable module.
   5
   6 Copyright (c) 2006 - 2008, Intel Corporation
   7 All rights reserved. This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #ifndef _PEI_VARIABLE_H_
  18 #define _PEI_VARIABLE_H_
  19
  20 #include <PiPei.h>
  21 #include <Ppi/ReadOnlyVariable2.h>
  22
  23 #include <Library/DebugLib.h>
  24 #include <Library/PeimEntryPoint.h>
  25 #include <Library/HobLib.h>
  26 #include <Library/PcdLib.h>
  27 #include <Library/BaseMemoryLib.h>
  28 #include <Library/PeiServicesTablePointerLib.h>
  29 #include <Library/PeiServicesLib.h>
  30
  31 #include <VariableFormat.h>
  32
  33 //
  34 // Define GET_PAD_SIZE to optimize compiler
  35 //
  36 #if ((ALIGNMENT == 0) || (ALIGNMENT == 1))
  37 #define GET_PAD_SIZE(a) (0)
  38 #else
  39 #define GET_PAD_SIZE(a) (((~a) + 1) & (ALIGNMENT - 1))
  40 #endif
  41
  42 #define HEADER_ALIGN(Header)  (((UINTN) (Header) + HEADER_ALIGNMENT - 1) & (~(HEADER_ALIGNMENT - 1)))
  43
  44 typedef struct {
  45   VARIABLE_HEADER *CurrPtr;
  46   VARIABLE_HEADER *EndPtr;
  47   VARIABLE_HEADER *StartPtr;
  48 } VARIABLE_POINTER_TRACK;
  49
  50 #define VARIABLE_INDEX_TABLE_VOLUME 122
  51
  52 #define EFI_VARIABLE_INDEX_TABLE_GUID \
  53   { 0x8cfdb8c8, 0xd6b2, 0x40f3, { 0x8e, 0x97, 0x02, 0x30, 0x7c, 0xc9, 0x8b, 0x7c } }
  54
  55 typedef struct {
  56   UINT16          Length;
  57   UINT16          GoneThrough;
  58   VARIABLE_HEADER *EndPtr;
  59   VARIABLE_HEADER *StartPtr;
  60   UINT16          Index[VARIABLE_INDEX_TABLE_VOLUME];
  61 } VARIABLE_INDEX_TABLE;
  62
  63
  64 //
  65 // Functions
  66 //
  67 /**
  68   Provide the functionality of the variable services.
  69
  70   @param  FileHandle  Handle of the file being invoked.
  71                       Type EFI_PEI_FILE_HANDLE is defined in FfsFindNextFile().
  72   @param  PeiServices  General purpose services available to every PEIM.
  73
  74   @retval EFI_SUCCESS  If the interface could be successfully installed
  75   @retval Others       Returned from PeiServicesInstallPpi()
  76
  77 **/
  78 EFI_STATUS
  79 EFIAPI
  80 PeimInitializeVariableServices (
  81   IN       EFI_PEI_FILE_HANDLE       FileHandle,
  82   IN CONST EFI_PEI_SERVICES          **PeiServices
  83   );
  84
  85 /**
  86   This service retrieves a variable's value using its name and GUID.
  87
  88   Read the specified variable from the UEFI variable store. If the Data
  89   buffer is too small to hold the contents of the variable, the error
  90   EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer
  91   size to obtain the data.
  92
  93   @param  This                  A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  94   @param  VariableName          A pointer to a null-terminated string that is the variable's name.
  95   @param  VariableGuid          A pointer to an EFI_GUID that is the variable's GUID. The combination of
  96                                 VariableGuid and VariableName must be unique.
  97   @param  Attributes            If non-NULL, on return, points to the variable's attributes.
  98   @param  DataSize              On entry, points to the size in bytes of the Data buffer.
  99                                 On return, points to the size of the data returned in Data.
 100   @param  Data                  Points to the buffer which will hold the returned variable value.
 101
 102   @retval EFI_SUCCESS           The variable was read successfully.
 103   @retval EFI_NOT_FOUND         The variable could not be found.
 104   @retval EFI_BUFFER_TOO_SMALL  The DataSize is too small for the resulting data.
 105                                 DataSize is updated with the size required for
 106                                 the specified variable.
 107   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.
 108   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 109
 110 **/
 111 EFI_STATUS
 112 EFIAPI
 113 PeiGetVariable (
 114   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 115   IN CONST  CHAR16                          *VariableName,
 116   IN CONST  EFI_GUID                        *VariableGuid,
 117   OUT       UINT32                          *Attributes,
 118   IN OUT    UINTN                           *DataSize,
 119   OUT       VOID                            *Data
 120   );
 121
 122 /**
 123   Return the next variable name and GUID.
 124
 125   This function is called multiple times to retrieve the VariableName
 126   and VariableGuid of all variables currently available in the system.
 127   On each call, the previous results are passed into the interface,
 128   and, on return, the interface returns the data for the next
 129   interface. When the entire variable list has been returned,
 130   EFI_NOT_FOUND is returned.
 131
 132   @param  This              A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
 133
 134   @param  VariableNameSize  On entry, points to the size of the buffer pointed to by VariableName.
 135   @param  VariableName      On entry, a pointer to a null-terminated string that is the variable's name.
 136                             On return, points to the next variable's null-terminated name string.
 137
 138   @param  VariableGuid      On entry, a pointer to an UEFI _GUID that is the variable's GUID.
 139                             On return, a pointer to the next variable's GUID.
 140
 141   @retval EFI_SUCCESS           The variable was read successfully.
 142   @retval EFI_NOT_FOUND         The variable could not be found.
 143   @retval EFI_BUFFER_TOO_SMALL  The VariableNameSize is too small for the resulting
 144                                 data. VariableNameSize is updated with the size
 145                                 required for the specified variable.
 146   @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or
 147                                 VariableNameSize is NULL.
 148   @retval EFI_DEVICE_ERROR      The variable could not be retrieved because of a device error.
 149
 150 **/
 151 EFI_STATUS
 152 EFIAPI
 153 PeiGetNextVariableName (
 154   IN CONST  EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
 155   IN OUT UINTN                              *VariableNameSize,
 156   IN OUT CHAR16                             *VariableName,
 157   IN OUT EFI_GUID                           *VariableGuid
 158   );
 159
 160 /**
 161   Get one variable by the index count.
 162
 163   @param  IndexTable  The pointer to variable index table.
 164   @param  Count       The index count of variable in index table.
 165
 166   @return The pointer to variable header indexed by count.
 167
 168 **/
 169 VARIABLE_HEADER *
 170 GetVariableByIndex (
 171   IN VARIABLE_INDEX_TABLE        *IndexTable,
 172   IN UINT32                      Count
 173   );
 174
 175 /**
 176   Record Variable in VariableIndex HOB.
 177
 178   Record Variable in VariableIndex HOB and update the length of variable index table.
 179
 180   @param  IndexTable  The pointer to variable index table.
 181   @param  Variable    The pointer to the variable that will be recorded.
 182
 183 **/
 184 VOID
 185 VariableIndexTableUpdate (
 186   IN OUT  VARIABLE_INDEX_TABLE   *IndexTable,
 187   IN      VARIABLE_HEADER        *Variable
 188   );
 189
 190 #endif