OvmfPkg/Library/NvVarsFileLib/NvVarsFileLib.h

   1 /** @file
   2   Save Non-Volatile Variables to a file system.
   3
   4   Copyright (c) 2009, Intel Corporation
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #ifndef __NV_VARS_FILE_LIB_INSTANCE__
  16 #define __NV_VARS_FILE_LIB_INSTANCE__
  17
  18 #include <Uefi.h>
  19
  20 #include <Guid/FileInfo.h>
  21
  22 #include <Protocol/SimpleFileSystem.h>
  23
  24 #include <Library/BaseLib.h>
  25 #include <Library/FileHandleLib.h>
  26 #include <Library/UefiBootServicesTableLib.h>
  27 #include <Library/UefiRuntimeServicesTableLib.h>
  28 #include <Library/UefiLib.h>
  29
  30 /**
  31   Loads the non-volatile variables from the NvVars file on the
  32   given file system.
  33
  34   @param[in]  FsHandle - Handle for a gEfiSimpleFileSystemProtocolGuid instance
  35
  36   @return     EFI_STATUS based on the success or failure of load operation
  37
  38 **/
  39 EFI_STATUS
  40 LoadNvVarsFromFs (
  41   EFI_HANDLE                            FsHandle
  42   );
  43
  44
  45 /**
  46   Saves the non-volatile variables into the NvVars file on the
  47   given file system.
  48
  49   @param[in]  FsHandle - Handle for a gEfiSimpleFileSystemProtocolGuid instance
  50
  51   @return     EFI_STATUS based on the success or failure of load operation
  52
  53 **/
  54 EFI_STATUS
  55 SaveNvVarsToFs (
  56   EFI_HANDLE                            FsHandle
  57   );
  58
  59
  60 /**
  61   Examines the NvVars file contents, and updates variables based on it.
  62
  63   @param[in]  VarsBuffer - Buffer with NvVars data
  64   @param[in]  VarsBufferSize - Size of VarsBuffer in bytes
  65
  66   @return     EFI_STATUS based on the success or failure of the operation
  67
  68 **/
  69 EFI_STATUS
  70 SetVariablesFromBuffer (
  71   IN VOID   *VarsBuffer,
  72   IN UINTN  VarsBufferSize
  73   );
  74
  75
  76 /**
  77   Writes the variable into the file so it can be restored from
  78   the file on future boots of the system.
  79
  80   @param[in]  File - The file to write to
  81   @param[in]  Name - Variable name string
  82   @param[in]  NameSize - Size of Name in bytes
  83   @param[in]  Guid - GUID of variable
  84   @param[in]  Attributes - Attributes of variable
  85   @param[in]  Data - Buffer containing Data for variable
  86   @param[in]  DataSize - Size of Data in bytes
  87
  88   @return     EFI_STATUS based on the success or failure of the operation
  89
  90 **/
  91 EFI_STATUS
  92 PackVariableIntoFile (
  93   IN EFI_FILE_HANDLE  File,
  94   IN CHAR16           *Name,
  95   IN UINT32           NameSize,
  96   IN EFI_GUID         *Guid,
  97   IN UINT32           Attributes,
  98   IN VOID             *Data,
  99   IN UINT32           DataSize
 100   );
 101
 102 #endif
 103