+/**\r
+ Mark a variable that will become read-only after leaving the DXE phase of execution.\r
+\r
+ @param[in] This The VARIABLE_LOCK_PROTOCOL instance.\r
+ @param[in] VariableName A pointer to the variable name that will be made read-only subsequently.\r
+ @param[in] VendorGuid A pointer to the vendor GUID that will be made read-only subsequently.\r
+\r
+ @retval EFI_SUCCESS The variable specified by the VariableName and the VendorGuid was marked\r
+ as pending to be read-only.\r
+ @retval EFI_INVALID_PARAMETER VariableName or VendorGuid is NULL.\r
+ Or VariableName is an empty string.\r
+ @retval EFI_ACCESS_DENIED EFI_END_OF_DXE_EVENT_GROUP_GUID or EFI_EVENT_GROUP_READY_TO_BOOT has\r
+ already been signaled.\r
+ @retval EFI_OUT_OF_RESOURCES There is not enough resource to hold the lock request.\r
+**/\r
+EFI_STATUS\r
+EFIAPI\r
+VariableLockRequestToLock (\r
+ IN CONST EDKII_VARIABLE_LOCK_PROTOCOL *This,\r
+ IN CHAR16 *VariableName,\r
+ IN EFI_GUID *VendorGuid\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ UINTN VariableNameSize;\r
+ UINTN PayloadSize;\r
+ SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE *VariableToLock;\r
+\r
+ if (VariableName == NULL || VariableName[0] == 0 || VendorGuid == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ VariableNameSize = StrSize (VariableName);\r
+ VariableToLock = NULL;\r
+\r
+ //\r
+ // If VariableName exceeds SMM payload limit. Return failure\r
+ //\r
+ if (VariableNameSize > mVariableBufferPayloadSize - OFFSET_OF (SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE, Name)) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ AcquireLockOnlyAtBootTime(&mVariableServicesLock);\r
+\r
+ //\r
+ // Init the communicate buffer. The buffer data size is:\r
+ // SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + PayloadSize.\r
+ //\r
+ PayloadSize = OFFSET_OF (SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE, Name) + VariableNameSize;\r
+ Status = InitCommunicateBuffer ((VOID **) &VariableToLock, PayloadSize, SMM_VARIABLE_FUNCTION_LOCK_VARIABLE);\r
+ if (EFI_ERROR (Status)) {\r
+ goto Done;\r
+ }\r
+ ASSERT (VariableToLock != NULL);\r
+\r
+ CopyGuid (&VariableToLock->Guid, VendorGuid);\r
+ VariableToLock->NameSize = VariableNameSize;\r
+ CopyMem (VariableToLock->Name, VariableName, VariableToLock->NameSize);\r
+\r
+ //\r
+ // Send data to SMM.\r
+ //\r
+ Status = SendCommunicateBuffer (PayloadSize);\r
+\r
+Done:\r
+ ReleaseLockOnlyAtBootTime (&mVariableServicesLock);\r
+ return Status;\r
+}\r