FirmwareVolume2.h File Reference

Data Structures
struct	EFI_FV_WRITE_FILE_DATA
struct	_EFI_FIRMWARE_VOLUME2_PROTOCOL

Macros
#define	EFI_FIRMWARE_VOLUME2_PROTOCOL_GUID   { 0x220e73b6, 0x6bdb, 0x4413, { 0x84, 0x5, 0xb9, 0x74, 0xb1, 0x8, 0x61, 0x9a } }
#define	EFI_FV2_READ_DISABLE_CAP   0x0000000000000001ULL
#define	EFI_FV2_READ_ENABLE_CAP   0x0000000000000002ULL
#define	EFI_FV2_READ_STATUS   0x0000000000000004ULL
#define	EFI_FV2_WRITE_DISABLE_CAP   0x0000000000000008ULL
#define	EFI_FV2_WRITE_ENABLE_CAP   0x0000000000000010ULL
#define	EFI_FV2_WRITE_STATUS   0x0000000000000020ULL
#define	EFI_FV2_LOCK_CAP   0x0000000000000040ULL
#define	EFI_FV2_LOCK_STATUS   0x0000000000000080ULL
#define	EFI_FV2_WRITE_POLICY_RELIABLE   0x0000000000000100ULL
#define	EFI_FV2_READ_LOCK_CAP   0x0000000000001000ULL
#define	EFI_FV2_READ_LOCK_STATUS   0x0000000000002000ULL
#define	EFI_FV2_WRITE_LOCK_CAP   0x0000000000004000ULL
#define	EFI_FV2_WRITE_LOCK_STATUS   0x0000000000008000ULL
#define	EFI_FV2_ALIGNMENT   0x00000000001F0000ULL
#define	EFI_FV2_ALIGNMENT_1   0x0000000000000000ULL
#define	EFI_FV2_ALIGNMENT_2   0x0000000000010000ULL
#define	EFI_FV2_ALIGNMENT_4   0x0000000000020000ULL
#define	EFI_FV2_ALIGNMENT_8   0x0000000000030000ULL
#define	EFI_FV2_ALIGNMENT_16   0x0000000000040000ULL
#define	EFI_FV2_ALIGNMENT_32   0x0000000000050000ULL
#define	EFI_FV2_ALIGNMENT_64   0x0000000000060000ULL
#define	EFI_FV2_ALIGNMENT_128   0x0000000000070000ULL
#define	EFI_FV2_ALIGNMENT_256   0x0000000000080000ULL
#define	EFI_FV2_ALIGNMENT_512   0x0000000000090000ULL
#define	EFI_FV2_ALIGNMENT_1K   0x00000000000A0000ULL
#define	EFI_FV2_ALIGNMENT_2K   0x00000000000B0000ULL
#define	EFI_FV2_ALIGNMENT_4K   0x00000000000C0000ULL
#define	EFI_FV2_ALIGNMENT_8K   0x00000000000D0000ULL
#define	EFI_FV2_ALIGNMENT_16K   0x00000000000E0000ULL
#define	EFI_FV2_ALIGNMENT_32K   0x00000000000F0000ULL
#define	EFI_FV2_ALIGNMENT_64K   0x0000000000100000ULL
#define	EFI_FV2_ALIGNMENT_128K   0x0000000000110000ULL
#define	EFI_FV2_ALIGNMENT_256K   0x0000000000120000ULL
#define	EFI_FV2_ALIGNMENT_512K   0x0000000000130000ULL
#define	EFI_FV2_ALIGNMENT_1M   0x0000000000140000ULL
#define	EFI_FV2_ALIGNMENT_2M   0x0000000000150000ULL
#define	EFI_FV2_ALIGNMENT_4M   0x0000000000160000ULL
#define	EFI_FV2_ALIGNMENT_8M   0x0000000000170000ULL
#define	EFI_FV2_ALIGNMENT_16M   0x0000000000180000ULL
#define	EFI_FV2_ALIGNMENT_32M   0x0000000000190000ULL
#define	EFI_FV2_ALIGNMENT_64M   0x00000000001A0000ULL
#define	EFI_FV2_ALIGNMENT_128M   0x00000000001B0000ULL
#define	EFI_FV2_ALIGNMENT_256M   0x00000000001C0000ULL
#define	EFI_FV2_ALIGNMENT_512M   0x00000000001D0000ULL
#define	EFI_FV2_ALIGNMENT_1G   0x00000000001E0000ULL
#define	EFI_FV2_ALIGNMENT_2G   0x00000000001F0000ULL
#define	EFI_FV_UNRELIABLE_WRITE   0x00000000
#define	EFI_FV_RELIABLE_WRITE   0x00000001

Typedefs
typedef struct _EFI_FIRMWARE_VOLUME2_PROTOCOL	EFI_FIRMWARE_VOLUME2_PROTOCOL
typedef UINT64	EFI_FV_ATTRIBUTES
typedef EFI_STATUS(EFIAPI *	EFI_FV_GET_ATTRIBUTES )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, OUT EFI_FV_ATTRIBUTES *FvAttributes)
typedef EFI_STATUS(EFIAPI *	EFI_FV_SET_ATTRIBUTES )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN OUT EFI_FV_ATTRIBUTES *FvAttributes)
typedef EFI_STATUS(EFIAPI *	EFI_FV_READ_FILE )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *NameGuid, IN OUT VOID **Buffer, IN OUT UINTN *BufferSize, OUT EFI_FV_FILETYPE *FoundType, OUT EFI_FV_FILE_ATTRIBUTES *FileAttributes, OUT UINT32 *AuthenticationStatus)
typedef EFI_STATUS(EFIAPI *	EFI_FV_READ_SECTION )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *NameGuid, IN EFI_SECTION_TYPE SectionType, IN UINTN SectionInstance, IN OUT VOID **Buffer, IN OUT UINTN *BufferSize, OUT UINT32 *AuthenticationStatus)
typedef UINT32	EFI_FV_WRITE_POLICY
typedef EFI_STATUS(EFIAPI *	EFI_FV_WRITE_FILE )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN UINT32 NumberOfFiles, IN EFI_FV_WRITE_POLICY WritePolicy, IN EFI_FV_WRITE_FILE_DATA *FileData)
typedef EFI_STATUS(EFIAPI *	EFI_FV_GET_NEXT_FILE )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN OUT VOID *Key, IN OUT EFI_FV_FILETYPE *FileType, OUT EFI_GUID *NameGuid, OUT EFI_FV_FILE_ATTRIBUTES *Attributes, OUT UINTN *Size)
typedef EFI_STATUS(EFIAPI *	EFI_FV_GET_INFO )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *InformationType, IN OUT UINTN *BufferSize, OUT VOID *Buffer)
typedef EFI_STATUS(EFIAPI *	EFI_FV_SET_INFO )(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *InformationType, IN UINTN BufferSize, IN CONST VOID *Buffer)

Variables
EFI_GUID	gEfiFirmwareVolume2ProtocolGuid

Detailed Description

The Firmware Volume Protocol provides file-level access to the firmware volume. Each firmware volume driver must produce an instance of the Firmware Volume Protocol if the firmware volume is to be visible to the system during the DXE phase. The Firmware Volume Protocol also provides mechanisms for determining and modifying some attributes of the firmware volume.

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Revision Reference: PI

Version 1.00.

Macro Definition Documentation

#define EFI_FIRMWARE_VOLUME2_PROTOCOL_GUID   { 0x220e73b6, 0x6bdb, 0x4413, { 0x84, 0x5, 0xb9, 0x74, 0xb1, 0x8, 0x61, 0x9a } }

#define EFI_FV2_ALIGNMENT   0x00000000001F0000ULL

#define EFI_FV2_ALIGNMENT_1   0x0000000000000000ULL

#define EFI_FV2_ALIGNMENT_128   0x0000000000070000ULL

#define EFI_FV2_ALIGNMENT_128K   0x0000000000110000ULL

#define EFI_FV2_ALIGNMENT_128M   0x00000000001B0000ULL

#define EFI_FV2_ALIGNMENT_16   0x0000000000040000ULL

#define EFI_FV2_ALIGNMENT_16K   0x00000000000E0000ULL

#define EFI_FV2_ALIGNMENT_16M   0x0000000000180000ULL

#define EFI_FV2_ALIGNMENT_1G   0x00000000001E0000ULL

#define EFI_FV2_ALIGNMENT_1K   0x00000000000A0000ULL

#define EFI_FV2_ALIGNMENT_1M   0x0000000000140000ULL

#define EFI_FV2_ALIGNMENT_2   0x0000000000010000ULL

#define EFI_FV2_ALIGNMENT_256   0x0000000000080000ULL

#define EFI_FV2_ALIGNMENT_256K   0x0000000000120000ULL

#define EFI_FV2_ALIGNMENT_256M   0x00000000001C0000ULL

#define EFI_FV2_ALIGNMENT_2G   0x00000000001F0000ULL

#define EFI_FV2_ALIGNMENT_2K   0x00000000000B0000ULL

#define EFI_FV2_ALIGNMENT_2M   0x0000000000150000ULL

#define EFI_FV2_ALIGNMENT_32   0x0000000000050000ULL

#define EFI_FV2_ALIGNMENT_32K   0x00000000000F0000ULL

#define EFI_FV2_ALIGNMENT_32M   0x0000000000190000ULL

#define EFI_FV2_ALIGNMENT_4   0x0000000000020000ULL

#define EFI_FV2_ALIGNMENT_4K   0x00000000000C0000ULL

#define EFI_FV2_ALIGNMENT_4M   0x0000000000160000ULL

#define EFI_FV2_ALIGNMENT_512   0x0000000000090000ULL

#define EFI_FV2_ALIGNMENT_512K   0x0000000000130000ULL

#define EFI_FV2_ALIGNMENT_512M   0x00000000001D0000ULL

#define EFI_FV2_ALIGNMENT_64   0x0000000000060000ULL

#define EFI_FV2_ALIGNMENT_64K   0x0000000000100000ULL

#define EFI_FV2_ALIGNMENT_64M   0x00000000001A0000ULL

#define EFI_FV2_ALIGNMENT_8   0x0000000000030000ULL

#define EFI_FV2_ALIGNMENT_8K   0x00000000000D0000ULL

#define EFI_FV2_ALIGNMENT_8M   0x0000000000170000ULL

#define EFI_FV2_LOCK_CAP   0x0000000000000040ULL

#define EFI_FV2_LOCK_STATUS   0x0000000000000080ULL

#define EFI_FV2_READ_DISABLE_CAP   0x0000000000000001ULL

#define EFI_FV2_READ_ENABLE_CAP   0x0000000000000002ULL

#define EFI_FV2_READ_LOCK_CAP   0x0000000000001000ULL

#define EFI_FV2_READ_LOCK_STATUS   0x0000000000002000ULL

#define EFI_FV2_READ_STATUS   0x0000000000000004ULL

#define EFI_FV2_WRITE_DISABLE_CAP   0x0000000000000008ULL

#define EFI_FV2_WRITE_ENABLE_CAP   0x0000000000000010ULL

#define EFI_FV2_WRITE_LOCK_CAP   0x0000000000004000ULL

#define EFI_FV2_WRITE_LOCK_STATUS   0x0000000000008000ULL

#define EFI_FV2_WRITE_POLICY_RELIABLE   0x0000000000000100ULL

#define EFI_FV2_WRITE_STATUS   0x0000000000000020ULL

#define EFI_FV_RELIABLE_WRITE   0x00000001

#define EFI_FV_UNRELIABLE_WRITE   0x00000000

Typedef Documentation

typedef struct _EFI_FIRMWARE_VOLUME2_PROTOCOL EFI_FIRMWARE_VOLUME2_PROTOCOL

typedef UINT64 EFI_FV_ATTRIBUTES

EFI_FV_ATTRIBUTES

typedef EFI_STATUS(EFIAPI * EFI_FV_GET_ATTRIBUTES)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, OUT EFI_FV_ATTRIBUTES *FvAttributes)

Returns the attributes and current settings of the firmware volume.

Because of constraints imposed by the underlying firmware storage, an instance of the Firmware Volume Protocol may not be to able to support all possible variations of this architecture. These constraints and the current state of the firmware volume are exposed to the caller using the GetVolumeAttributes() function. GetVolumeAttributes() is callable only from TPL_NOTIFY and below. Behavior of GetVolumeAttributes() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
FvAttributes	Pointer to an EFI_FV_ATTRIBUTES in which the attributes and current settings are returned.

Return values

EFI_SUCCESS

The firmware volume attributes were returned.

typedef EFI_STATUS(EFIAPI * EFI_FV_GET_INFO)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *InformationType, IN OUT UINTN *BufferSize, OUT VOID *Buffer)

Return information about a firmware volume.

The GetInfo() function returns information of type InformationType for the requested firmware volume. If the volume does not support the requested information type, then EFI_UNSUPPORTED is returned. If the buffer is not large enough to hold the requested structure, EFI_BUFFER_TOO_SMALL is returned and the BufferSize is set to the size of buffer that is required to make the request. The information types defined by this specification are required information types that all file systems must support.

Parameters

This	A pointer to the EFI_FIRMWARE_VOLUME2_PROTOCOL instance that is the file handle the requested information is for.
InformationType	The type identifier for the information being requested.
BufferSize	On input, the size of Buffer. On output, the amount of data returned in Buffer. In both cases, the size is measured in bytes.
Buffer	A pointer to the data buffer to return. The buffer's type is indicated by InformationType.

Return values

EFI_SUCCESS	The information was retrieved.
EFI_UNSUPPORTED	The InformationType is not known.
EFI_NO_MEDIA	The device has no medium.
EFI_DEVICE_ERROR	The device reported an error.
EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
EFI_BUFFER_TOO_SMALL	The BufferSize is too small to read the current directory entry. BufferSize has been updated with the size needed to complete the request.

typedef EFI_STATUS(EFIAPI * EFI_FV_GET_NEXT_FILE)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN OUT VOID *Key, IN OUT EFI_FV_FILETYPE *FileType, OUT EFI_GUID *NameGuid, OUT EFI_FV_FILE_ATTRIBUTES *Attributes, OUT UINTN *Size)

Retrieves information about the next file in the firmware volume store that matches the search criteria.

GetNextFile() is the interface that is used to search a firmware volume for a particular file. It is called successively until the desired file is located or the function returns EFI_NOT_FOUND. To filter uninteresting files from the output, the type of file to search for may be specified in FileType. For example, if *FileType is EFI_FV_FILETYPE_DRIVER, only files of this type will be returned in the output. If *FileType is EFI_FV_FILETYPE_ALL, no filtering of file types is done. The Key parameter is used to indicate a starting point of the search. If the buffer *Key is completely initialized to zero, the search re-initialized and starts at the beginning. Subsequent calls to GetNextFile() must maintain the value of *Key returned by the immediately previous call. The actual contents of *Key are implementation specific and no semantic content is implied. GetNextFile() is callable only from TPL_NOTIFY and below. Behavior of GetNextFile() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
Key	Pointer to a caller-allocated buffer that contains implementation-specific data that is used to track where to begin the search for the next file. The size of the buffer must be at least This->KeySize bytes long. To re-initialize the search and begin from the beginning of the firmware volume, the entire buffer must be cleared to zero. Other than clearing the buffer to initiate a new search, the caller must not modify the data in the buffer between calls to GetNextFile().
FileType	Pointer to a caller-allocated EFI_FV_FILETYPE. The GetNextFile() API can filter its search for files based on the value of the FileType input. A *FileType input of EFI_FV_FILETYPE_ALL causes GetNextFile() to search for files of all types. If a file is found, the file's type is returned in FileType. *FileType is not modified if no file is found.
NameGuid	Pointer to a caller-allocated EFI_GUID. If a matching file is found, the file's name is returned in NameGuid. If no matching file is found, *NameGuid is not modified.
Attributes	Pointer to a caller-allocated EFI_FV_FILE_ATTRIBUTES. If a matching file is found, the file's attributes are returned in Attributes. If no matching file is found, Attributes is not modified. Type EFI_FV_FILE_ATTRIBUTES is defined in ReadFile().
Size	Pointer to a caller-allocated UINTN. If a matching file is found, the file's size is returned in *Size. If no matching file is found, Size is not modified.

Return values

EFI_SUCCESS	The output parameters are filled with data obtained from the first matching file that was found.
FI_NOT_FOUND	No files of type FileType were found.
EFI_DEVICE_ERROR	A hardware error occurred when attempting to access the firmware volume.
EFI_ACCESS_DENIED	The firmware volume is configured to disallow reads.

typedef EFI_STATUS(EFIAPI * EFI_FV_READ_FILE)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *NameGuid, IN OUT VOID **Buffer, IN OUT UINTN *BufferSize, OUT EFI_FV_FILETYPE *FoundType, OUT EFI_FV_FILE_ATTRIBUTES *FileAttributes, OUT UINT32 *AuthenticationStatus)

Retrieves a file and/or file information from the firmware volume.

ReadFile() is used to retrieve any file from a firmware volume during the DXE phase. The actual binary encoding of the file in the firmware volume media may be in any arbitrary format as long as it does the following: It is accessed using the Firmware Volume Protocol. The image that is returned follows the image format defined in Code Definitions: PI Firmware File Format. If the input value of Buffer==NULL, it indicates the caller is requesting only that the type, attributes, and size of the file be returned and that there is no output buffer. In this case, the following occurs:

• BufferSize is returned with the size that is required to successfully complete the read.
• The output parameters FoundType and *FileAttributes are returned with valid values.
• The returned value of *AuthenticationStatus is undefined.

If the input value of Buffer!=NULL, the output buffer is specified by a double indirection of the Buffer parameter. The input value of *Buffer is used to determine if the output buffer is caller allocated or is dynamically allocated by ReadFile(). If the input value of *Buffer!=NULL, it indicates the output buffer is caller allocated. In this case, the input value of *BufferSize indicates the size of the caller-allocated output buffer. If the output buffer is not large enough to contain the entire requested output, it is filled up to the point that the output buffer is exhausted and EFI_WARN_BUFFER_TOO_SMALL is returned, and then BufferSize is returned with the size required to successfully complete the read. All other output parameters are returned with valid values. If the input value of *Buffer==NULL, it indicates the output buffer is to be allocated by ReadFile(). In this case, ReadFile() will allocate an appropriately sized buffer from boot services pool memory, which will be returned in Buffer. The size of the new buffer is returned in BufferSize and all other output parameters are returned with valid values. ReadFile() is callable only from TPL_NOTIFY and below. Behavior of ReadFile() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
NameGuid	Pointer to an EFI_GUID, which is the file name. All firmware file names are EFI_GUIDs. A single firmware volume must not have two valid files with the same file name EFI_GUID.
Buffer	Pointer to a pointer to a buffer in which the file contents are returned, not including the file header.
BufferSize	Pointer to a caller-allocated UINTN. It indicates the size of the memory represented by Buffer.
FoundType	Pointer to a caller-allocated EFI_FV_FILETYPE.
FileAttributes	Pointer to a caller-allocated EFI_FV_FILE_ATTRIBUTES.
AuthenticationStatus	Pointer to a caller-allocated UINT32 in which the authentication status is returned.

Return values

EFI_SUCCESS	The call completed successfully.
EFI_WARN_BUFFER_TOO_SMALL	The buffer is too small to contain the requested output. The buffer is filled and the output is truncated.
EFI_OUT_OF_RESOURCES	An allocation failure occurred.
EFI_NOT_FOUND	Name was not found in the firmware volume.
EFI_DEVICE_ERROR	A hardware error occurred when attempting to access the firmware volume.
EFI_ACCESS_DENIED	The firmware volume is configured to disallow reads.

typedef EFI_STATUS(EFIAPI * EFI_FV_READ_SECTION)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *NameGuid, IN EFI_SECTION_TYPE SectionType, IN UINTN SectionInstance, IN OUT VOID **Buffer, IN OUT UINTN *BufferSize, OUT UINT32 *AuthenticationStatus)

Locates the requested section within a file and returns it in a buffer.

ReadSection() is used to retrieve a specific section from a file within a firmware volume. The section returned is determined using a depth-first, left-to-right search algorithm through all sections found in the specified file. The output buffer is specified by a double indirection of the Buffer parameter. The input value of Buffer is used to determine if the output buffer is caller allocated or is dynamically allocated by ReadSection(). If the input value of Buffer!=NULL, it indicates that the output buffer is caller allocated. In this case, the input value of *BufferSize indicates the size of the caller-allocated output buffer. If the output buffer is not large enough to contain the entire requested output, it is filled up to the point that the output buffer is exhausted and EFI_WARN_BUFFER_TOO_SMALL is returned, and then BufferSize is returned with the size that is required to successfully complete the read. All other output parameters are returned with valid values. If the input value of *Buffer==NULL, it indicates the output buffer is to be allocated by ReadSection(). In this case, ReadSection() will allocate an appropriately sized buffer from boot services pool memory, which will be returned in *Buffer. The size of the new buffer is returned in *BufferSize and all other output parameters are returned with valid values. ReadSection() is callable only from TPL_NOTIFY and below. Behavior of ReadSection() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
NameGuid	Pointer to an EFI_GUID, which indicates the file name from which the requested section will be read.
SectionType	Indicates the section type to return. SectionType in conjunction with SectionInstance indicates which section to return.
SectionInstance	Indicates which instance of sections with a type of SectionType to return. SectionType in conjunction with SectionInstance indicates which section to return. SectionInstance is zero based.
Buffer	Pointer to a pointer to a buffer in which the section contents are returned, not including the section header.
BufferSize	Pointer to a caller-allocated UINTN. It indicates the size of the memory represented by Buffer.
AuthenticationStatus	Pointer to a caller-allocated UINT32 in which the authentication status is returned.

Return values

EFI_SUCCESS	The call completed successfully.
EFI_WARN_BUFFER_TOO_SMALL	The caller-allocated buffer is too small to contain the requested output. The buffer is filled and the output is truncated.
EFI_OUT_OF_RESOURCES	An allocation failure occurred.
EFI_NOT_FOUND	The requested file was not found in the firmware volume. EFI_NOT_FOUND The requested section was not found in the specified file.
EFI_DEVICE_ERROR	A hardware error occurred when attempting to access the firmware volume.
EFI_ACCESS_DENIED	The firmware volume is configured to disallow reads. EFI_PROTOCOL_ERROR The requested section was not found, but the file could not be fully parsed because a required GUIDED_SECTION_EXTRACTION_PROTOCOL was not found. It is possible the requested section exists within the file and could be successfully extracted once the required GUIDED_SECTION_EXTRACTION_PROTOCOL is published.

typedef EFI_STATUS(EFIAPI * EFI_FV_SET_ATTRIBUTES)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN OUT EFI_FV_ATTRIBUTES *FvAttributes)

Modifies the current settings of the firmware volume according to the input parameter.

The SetVolumeAttributes() function is used to set configurable firmware volume attributes. Only EFI_FV_READ_STATUS, EFI_FV_WRITE_STATUS, and EFI_FV_LOCK_STATUS may be modified, and then only in accordance with the declared capabilities. All other bits of FvAttributes are ignored on input. On successful return, all bits of *FvAttributes are valid and it contains the completed EFI_FV_ATTRIBUTES for the volume. To modify an attribute, the corresponding status bit in the EFI_FV_ATTRIBUTES is set to the desired value on input. The EFI_FV_LOCK_STATUS bit does not affect the ability to read or write the firmware volume. Rather, once the EFI_FV_LOCK_STATUS bit is set, it prevents further modification to all the attribute bits. SetVolumeAttributes() is callable only from TPL_NOTIFY and below. Behavior of SetVolumeAttributes() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
FvAttributes	On input, FvAttributes is a pointer to an EFI_FV_ATTRIBUTES containing the desired firmware volume settings. On successful return, it contains the new settings of the firmware volume. On unsuccessful return, FvAttributes is not modified and the firmware volume settings are not changed.

Return values

EFI_SUCCESS	The requested firmware volume attributes were set and the resulting EFI_FV_ATTRIBUTES is returned in FvAttributes.
EFI_INVALID_PARAMETER	FvAttributes:EFI_FV_READ_STATUS is set to 1 on input, but the device does not support enabling reads (FvAttributes:EFI_FV_READ_ENABLE is clear on return from GetVolumeAttributes()). Actual volume attributes are unchanged.
EFI_INVALID_PARAMETER	FvAttributes:EFI_FV_READ_STATUS is cleared to 0 on input, but the device does not support disabling reads (FvAttributes:EFI_FV_READ_DISABL is clear on return from GetVolumeAttributes()). Actual volume attributes are unchanged.
EFI_INVALID_PARAMETER	FvAttributes:EFI_FV_WRITE_STATUS is set to 1 on input, but the device does not support enabling writes (FvAttributes:EFI_FV_WRITE_ENABL is clear on return from GetVolumeAttributes()). Actual volume attributes are unchanged.
EFI_INVALID_PARAMETER	FvAttributes:EFI_FV_WRITE_STATUS is cleared to 0 on input, but the device does not support disabling writes (FvAttributes:EFI_FV_WRITE_DISAB is clear on return from GetVolumeAttributes()). Actual volume attributes are unchanged.
EFI_INVALID_PARAMETER	FvAttributes:EFI_FV_LOCK_STATUS is set on input, but the device does not support locking (FvAttributes:EFI_FV_LOCK_CAP is clear on return from GetVolumeAttributes()). Actual volume attributes are unchanged.
EFI_ACCESS_DENIED	Device is locked and does not allow attribute modification (FvAttributes:EFI_FV_LOCK_STATUS is set on return from GetVolumeAttributes()). Actual volume attributes are unchanged.

typedef EFI_STATUS(EFIAPI * EFI_FV_SET_INFO)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN CONST EFI_GUID *InformationType, IN UINTN BufferSize, IN CONST VOID *Buffer)

Sets information about a firmware volume.

The SetInfo() function sets information of type InformationType on the requested firmware volume.

Parameters

This	A pointer to the EFI_FIRMWARE_VOLUME2_PROTOCOL instance that is the file handle the information is for.
InformationType	The type identifier for the information being set.
BufferSize	The size, in bytes, of Buffer.
Buffer	A pointer to the data buffer to write. The buffer's type is indicated by InformationType.

Return values

EFI_SUCCESS	The information was set.
EFI_UNSUPPORTED	The InformationType is not known.
EFI_NO_MEDIA	The device has no medium.
EFI_DEVICE_ERROR	The device reported an error.
EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
EFI_WRITE_PROTECTED	The media is read only.
EFI_VOLUME_FULL	The volume is full.
EFI_BAD_BUFFER_SIZE	BufferSize is smaller than the size of the type indicated by InformationType.

typedef EFI_STATUS(EFIAPI * EFI_FV_WRITE_FILE)(IN CONST EFI_FIRMWARE_VOLUME2_PROTOCOL *This, IN UINT32 NumberOfFiles, IN EFI_FV_WRITE_POLICY WritePolicy, IN EFI_FV_WRITE_FILE_DATA *FileData)

Locates the requested section within a file and returns it in a buffer.

WriteFile() is used to write one or more files to a firmware volume. Each file to be written is described by an EFI_FV_WRITE_FILE_DATA structure. The caller must ensure that any required alignment for all files listed in the FileData array is compatible with the firmware volume. Firmware volume capabilities can be determined using the GetVolumeAttributes() call. Similarly, if the WritePolicy is set to EFI_FV_RELIABLE_WRITE, the caller must check the firmware volume capabilities to ensure EFI_FV_RELIABLE_WRITE is supported by the firmware volume. EFI_FV_UNRELIABLE_WRITE must always be supported. Writing a file with a size of zero (FileData[n].BufferSize == 0) deletes the file from the firmware volume if it exists. Deleting a file must be done one at a time. Deleting a file as part of a multiple file write is not allowed. Platform Initialization Specification VOLUME 3 Shared Architectural Elements 84 August 21, 2006 Version 1.0 WriteFile() is callable only from TPL_NOTIFY and below. Behavior of WriteFile() at any EFI_TPL above TPL_NOTIFY is undefined.

Parameters

This	Indicates the EFI_FIRMWARE_VOLUME2_PROTOCOL instance.
NumberOfFiles	Indicates the number of elements in the array pointed to by FileData
WritePolicy	Indicates the level of reliability for the write in the event of a power failure or other system failure during the write operation.
FileData	Pointer to an array of EFI_FV_WRITE_FILE_DATA. Each element of FileData[] represents a file to be written.

Return values

EFI_SUCCESS	The write completed successfully.
EFI_OUT_OF_RESOURCES	The firmware volume does not have enough free space to storefile(s).
EFI_DEVICE_ERROR	A hardware error occurred when attempting to access the firmware volume.
EFI_WRITE_PROTECTED	The firmware volume is configured to disallow writes.
EFI_NOT_FOUND	A delete was requested, but the requested file was not found in the firmware volume.
EFI_INVALID_PARAMETER	A delete was requested with a multiple file write.
EFI_INVALID_PARAMETER	An unsupported WritePolicy was requested.
EFI_INVALID_PARAMETER	An unknown file type was specified.
EFI_INVALID_PARAMETER	A file system specific error has occurred.

typedef UINT32 EFI_FV_WRITE_POLICY

EFI_FV_WRITE_POLICY, two policies (unreliable write and reliable write) are defined.

Variable Documentation

EFI_GUID gEfiFirmwareVolume2ProtocolGuid