audk/OvmfPkg/Library/NvVarsFileLib/NvVarsFileLib.c

84 lines
2.2 KiB
C

/** @file
Save Non-Volatile Variables to a file system.
Copyright (c) 2009, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "NvVarsFileLib.h"
#include <Library/DebugLib.h>
#include <Library/NvVarsFileLib.h>
EFI_HANDLE mNvVarsFileLibFsHandle = NULL;
/**
Attempts to connect the NvVarsFileLib to the specified file system.
@param[in] FsHandle - Handle for a gEfiSimpleFileSystemProtocolGuid instance
@return The EFI_STATUS while attempting to connect the NvVarsFileLib
to the file system instance.
@retval EFI_SUCCESS - The given file system was connected successfully
**/
EFI_STATUS
EFIAPI
ConnectNvVarsToFileSystem (
IN EFI_HANDLE FsHandle
)
{
EFI_STATUS Status;
//
// We might fail to load the variable, since the file system initially
// will not have the NvVars file.
//
LoadNvVarsFromFs (FsHandle);
//
// We must be able to save the variables successfully to the file system
// to have connected successfully.
//
Status = SaveNvVarsToFs (FsHandle);
if (!EFI_ERROR (Status)) {
mNvVarsFileLibFsHandle = FsHandle;
}
return Status;
}
/**
Update non-volatile variables stored on the file system.
@return The EFI_STATUS while attempting to update the variable on
the connected file system.
@retval EFI_SUCCESS - The non-volatile variables were saved to the disk
@retval EFI_NOT_STARTED - A file system has not been connected
**/
EFI_STATUS
EFIAPI
UpdateNvVarsOnFileSystem (
)
{
if (mNvVarsFileLibFsHandle == NULL) {
//
// A file system had not been connected to the library.
//
return EFI_NOT_STARTED;
} else {
return SaveNvVarsToFs (mNvVarsFileLibFsHandle);
}
}