1 /** @file
2   Variable Lock Protocol is related to EDK II-specific implementation of variables
3   and intended for use as a means to mark a variable read-only after the event
4   EFI_END_OF_DXE_EVENT_GUID is signaled.
5 
6   Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>
7   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 __VARIABLE_LOCK_H__
18 #define __VARIABLE_LOCK_H__
19 
20 #define EDKII_VARIABLE_LOCK_PROTOCOL_GUID \
21   { \
22     0xcd3d0a05, 0x9e24, 0x437c, { 0xa8, 0x91, 0x1e, 0xe0, 0x53, 0xdb, 0x76, 0x38 } \
23   }
24 
25 typedef struct _EDKII_VARIABLE_LOCK_PROTOCOL  EDKII_VARIABLE_LOCK_PROTOCOL;
26 
27 /**
28   Mark a variable that will become read-only after leaving the DXE phase of execution.
29   Write request coming from SMM environment through EFI_SMM_VARIABLE_PROTOCOL is allowed.
30 
31   @param[in] This          The EDKII_VARIABLE_LOCK_PROTOCOL instance.
32   @param[in] VariableName  A pointer to the variable name that will be made read-only subsequently.
33   @param[in] VendorGuid    A pointer to the vendor GUID that will be made read-only subsequently.
34 
35   @retval EFI_SUCCESS           The variable specified by the VariableName and the VendorGuid was marked
36                                 as pending to be read-only.
37   @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.
38                                 Or VariableName is an empty string.
39   @retval EFI_ACCESS_DENIED     EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has
40                                 already been signaled.
41   @retval EFI_OUT_OF_RESOURCES  There is not enough resource to hold the lock request.
42 **/
43 typedef
44 EFI_STATUS
45 (EFIAPI * EDKII_VARIABLE_LOCK_PROTOCOL_REQUEST_TO_LOCK) (
46   IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,
47   IN       CHAR16                       *VariableName,
48   IN       EFI_GUID                     *VendorGuid
49   );
50 
51 ///
52 /// Variable Lock Protocol is related to EDK II-specific implementation of variables
53 /// and intended for use as a means to mark a variable read-only after the event
54 /// EFI_END_OF_DXE_EVENT_GUID is signaled.
55 ///
56 struct _EDKII_VARIABLE_LOCK_PROTOCOL {
57   EDKII_VARIABLE_LOCK_PROTOCOL_REQUEST_TO_LOCK RequestToLock;
58 };
59 
60 extern EFI_GUID gEdkiiVariableLockProtocolGuid;
61 
62 #endif
63 
64