[mirror_edk2.git] / EdkModulePkg / Universal / EmuVariable / RuntimeDxe / EmuVariable.c

/*++\r
\r
Copyright (c) 2006 - 2007, Intel Corporation\r
All rights reserved. This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution.  The full text of the license may be found at\r
http://opensource.org/licenses/bsd-license.php\r
\r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
Module Name:\r
\r
    EmuVariable.c\r
\r
Abstract:\r
\r
Revision History\r
\r
--*/\r
\r
#include "Variable.h"\r
\r
//\r
// Don't use module globals after the SetVirtualAddress map is signaled\r
//\r
ESAL_VARIABLE_GLOBAL  *mVariableModuleGlobal;\r
\r
//\r
// This is a temperary function which will be removed \r
// when EfiAcquireLock in UefiLib can handle the\r
// the call in UEFI Runtimer driver in RT phase.\r
//\r
STATIC\r
VOID\r
AcquireLockOnlyAtBootTime (\r
  IN EFI_LOCK  *Lock\r
  )\r
{\r
  if (!EfiAtRuntime ()) {\r
    EfiAcquireLock (Lock);\r
  }\r
}\r
\r
//\r
// This is a temperary function which will be removed \r
// when EfiAcquireLock in UefiLib can handle the\r
// the call in UEFI Runtimer driver in RT phase.\r
//\r
STATIC\r
VOID\r
ReleaseLockOnlyAtBootTime (\r
  IN EFI_LOCK  *Lock\r
  )\r
{\r
  if (!EfiAtRuntime ()) {\r
    EfiReleaseLock (Lock);\r
  }\r
}\r
\r
\r
STATIC\r
UINT32\r
EFIAPI\r
ArrayLength (\r
  IN CHAR16 *String\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  Determine the length of null terminated char16 array.\r
\r
Arguments:\r
\r
  String    Null-terminated CHAR16 array pointer.\r
\r
Returns:\r
\r
  UINT32    Number of bytes in the string, including the double NULL at the end;\r
\r
--*/\r
{\r
  UINT32  Count;\r
\r
  if (NULL == String) {\r
    return 0;\r
  }\r
\r
  Count = 0;\r
\r
  while (0 != String[Count]) {\r
    Count++;\r
  }\r
\r
  return (Count * 2) + 2;\r
}\r
\r
STATIC\r
UINT8 *\r
EFIAPI\r
GetVariableDataPtr (\r
  IN  VARIABLE_HEADER   *Variable\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code gets the pointer to the variable data.\r
\r
Arguments:\r
\r
  Variable            Pointer to the Variable Header.\r
\r
Returns:\r
\r
  UINT8*              Pointer to Variable Data\r
\r
--*/\r
{\r
  if (Variable->StartId != VARIABLE_DATA) {\r
    return NULL;\r
  }\r
  //\r
  // Be careful about pad size for alignment\r
  //\r
  return (UINT8 *) ((UINTN) GET_VARIABLE_NAME_PTR (Variable) + Variable->NameSize + GET_PAD_SIZE (Variable->NameSize));\r
}\r
\r
STATIC\r
VARIABLE_HEADER *\r
EFIAPI\r
GetNextVariablePtr (\r
  IN  VARIABLE_HEADER   *Variable\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code gets the pointer to the next variable header.\r
\r
Arguments:\r
\r
  Variable                  Pointer to the Variable Header.\r
\r
Returns:\r
\r
  VARIABLE_HEADER*      Pointer to next variable header.\r
\r
--*/\r
{\r
  VARIABLE_HEADER *VarHeader;\r
\r
  if (Variable->StartId != VARIABLE_DATA) {\r
    return NULL;\r
  }\r
  //\r
  // Be careful about pad size for alignment\r
  //\r
  VarHeader = (VARIABLE_HEADER *) (GetVariableDataPtr (Variable) + Variable->DataSize + GET_PAD_SIZE (Variable->DataSize));\r
\r
  if (VarHeader->StartId != VARIABLE_DATA ||\r
      (sizeof (VARIABLE_HEADER) + VarHeader->DataSize + VarHeader->NameSize) > MAX_VARIABLE_SIZE\r
      ) {\r
    return NULL;\r
  }\r
\r
  return VarHeader;\r
}\r
\r
STATIC\r
VARIABLE_HEADER *\r
EFIAPI\r
GetEndPointer (\r
  IN VARIABLE_STORE_HEADER       *VolHeader\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code gets the pointer to the last variable memory pointer byte\r
\r
Arguments:\r
\r
  Variable                  Pointer to the Variable Header.\r
\r
Returns:\r
\r
  VARIABLE_HEADER*      Pointer to last unavailable Variable Header\r
\r
--*/\r
{\r
  //\r
  // The end of variable store\r
  //\r
  return (VARIABLE_HEADER *) ((UINTN) VolHeader + VolHeader->Size);\r
}\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
FindVariable (\r
  IN  CHAR16                  *VariableName,\r
  IN  EFI_GUID                *VendorGuid,\r
  OUT VARIABLE_POINTER_TRACK  *PtrTrack,\r
  IN  VARIABLE_GLOBAL         *Global\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code finds variable in storage blocks (Volatile or Non-Volatile)\r
\r
Arguments:\r
\r
  VariableName                Name of the variable to be found\r
  VendorGuid                  Vendor GUID to be found.\r
  PtrTrack                    Variable Track Pointer structure that contains\r
                              Variable Information.\r
                              Contains the pointer of Variable header.\r
  Global                      VARIABLE_GLOBAL pointer\r
\r
Returns:\r
\r
  EFI STATUS\r
\r
--*/\r
{\r
  VARIABLE_HEADER       *Variable[2];\r
  VARIABLE_STORE_HEADER *VariableStoreHeader[2];\r
  UINTN                 Index;\r
\r
  //\r
  // We aquire the lock at the entry of FindVariable as GetVariable, GetNextVariableName\r
  // SetVariable all call FindVariable at entry point. Please move "Aquire Lock" to\r
  // the correct places if this assumption does not hold TRUE anymore.\r
  //\r
  AcquireLockOnlyAtBootTime(&Global->VariableServicesLock);\r
\r
  //\r
  // 0: Non-Volatile, 1: Volatile\r
  //\r
  VariableStoreHeader[0]  = (VARIABLE_STORE_HEADER *) ((UINTN) Global->NonVolatileVariableBase);\r
  VariableStoreHeader[1]  = (VARIABLE_STORE_HEADER *) ((UINTN) Global->VolatileVariableBase);\r
\r
  //\r
  // Start Pointers for the variable.\r
  // Actual Data Pointer where data can be written.\r
  //\r
  Variable[0] = (VARIABLE_HEADER *) (VariableStoreHeader[0] + 1);\r
  Variable[1] = (VARIABLE_HEADER *) (VariableStoreHeader[1] + 1);\r
\r
  if (VariableName[0] != 0 && VendorGuid == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
  //\r
  // Find the variable by walk through non-volatile and volatile variable store\r
  //\r
  for (Index = 0; Index < 2; Index++) {\r
    PtrTrack->StartPtr  = (VARIABLE_HEADER *) (VariableStoreHeader[Index] + 1);\r
    PtrTrack->EndPtr    = GetEndPointer (VariableStoreHeader[Index]);\r
\r
    while ((Variable[Index] != NULL) && (Variable[Index] <= GetEndPointer (VariableStoreHeader[Index]))) {\r
      if (Variable[Index]->StartId == VARIABLE_DATA && Variable[Index]->State == VAR_ADDED) {\r
        if (!(EfiAtRuntime () && !(Variable[Index]->Attributes & EFI_VARIABLE_RUNTIME_ACCESS))) {\r
          if (VariableName[0] == 0) {\r
            PtrTrack->CurrPtr   = Variable[Index];\r
            PtrTrack->Volatile  = (BOOLEAN) Index;\r
            return EFI_SUCCESS;\r
          } else {\r
            if (CompareGuid (VendorGuid, &Variable[Index]->VendorGuid)) {\r
              if (!CompareMem (VariableName, GET_VARIABLE_NAME_PTR (Variable[Index]), ArrayLength (VariableName))) {\r
                PtrTrack->CurrPtr   = Variable[Index];\r
                PtrTrack->Volatile  = (BOOLEAN) Index;\r
                return EFI_SUCCESS;\r
              }\r
            }\r
          }\r
        }\r
      }\r
\r
      Variable[Index] = GetNextVariablePtr (Variable[Index]);\r
    }\r
  }\r
  PtrTrack->CurrPtr = NULL;\r
  return EFI_NOT_FOUND;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
GetVariable (\r
  IN      CHAR16            *VariableName,\r
  IN      EFI_GUID          * VendorGuid,\r
  OUT     UINT32            *Attributes OPTIONAL,\r
  IN OUT  UINTN             *DataSize,\r
  OUT     VOID              *Data,\r
  IN      VARIABLE_GLOBAL   * Global,\r
  IN      UINT32            Instance\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code finds variable in storage blocks (Volatile or Non-Volatile)\r
\r
Arguments:\r
\r
  VariableName                    Name of Variable to be found\r
  VendorGuid                      Variable vendor GUID\r
  Attributes OPTIONAL             Attribute value of the variable found\r
  DataSize                        Size of Data found. If size is less than the\r
                                  data, this value contains the required size.\r
  Data                            Data pointer\r
  Global                          Pointer to VARIABLE_GLOBAL structure\r
  Instance                        Instance of the Firmware Volume.\r
\r
Returns:\r
\r
  EFI STATUS\r
\r
--*/\r
{\r
  VARIABLE_POINTER_TRACK  Variable;\r
  UINTN                   VarDataSize;\r
  EFI_STATUS              Status;\r
\r
  if (VariableName == NULL || VendorGuid == NULL || DataSize == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
  //\r
  // Find existing variable\r
  //\r
  Status = FindVariable (VariableName, VendorGuid, &Variable, Global);\r
\r
  if (Variable.CurrPtr == NULL || EFI_ERROR (Status)) {\r
    goto Done;\r
  }\r
  //\r
  // Get data size\r
  //\r
  VarDataSize = Variable.CurrPtr->DataSize;\r
  if (*DataSize >= VarDataSize) {\r
    if (Data == NULL) {\r
      Status = EFI_INVALID_PARAMETER;\r
      goto Done;\r
    }\r
\r
    CopyMem (Data, GetVariableDataPtr (Variable.CurrPtr), VarDataSize);\r
    if (Attributes != NULL) {\r
      *Attributes = Variable.CurrPtr->Attributes;\r
    }\r
\r
    *DataSize = VarDataSize;\r
    Status = EFI_SUCCESS;\r
    goto Done;\r
  } else {\r
    *DataSize = VarDataSize;\r
    Status = EFI_BUFFER_TOO_SMALL;\r
    goto Done;\r
  }\r
\r
Done:\r
  ReleaseLockOnlyAtBootTime (&Global->VariableServicesLock);\r
  return Status;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
GetNextVariableName (\r
  IN OUT  UINTN             *VariableNameSize,\r
  IN OUT  CHAR16            *VariableName,\r
  IN OUT  EFI_GUID          *VendorGuid,\r
  IN      VARIABLE_GLOBAL   *Global,\r
  IN      UINT32            Instance\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code Finds the Next available variable\r
\r
Arguments:\r
\r
  VariableNameSize            Size of the variable\r
  VariableName                Pointer to variable name\r
  VendorGuid                  Variable Vendor Guid\r
  Global                      VARIABLE_GLOBAL structure pointer.\r
  Instance                    FV instance\r
\r
Returns:\r
\r
  EFI STATUS\r
\r
--*/\r
{\r
  VARIABLE_POINTER_TRACK  Variable;\r
  UINTN                   VarNameSize;\r
  EFI_STATUS              Status;\r
\r
  if (VariableNameSize == NULL || VariableName == NULL || VendorGuid == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  Status = FindVariable (VariableName, VendorGuid, &Variable, Global);\r
\r
  if (Variable.CurrPtr == NULL || EFI_ERROR (Status)) {\r
    goto Done;\r
  }\r
\r
  while (TRUE) {\r
    if (VariableName[0] != 0) {\r
      //\r
      // If variable name is not NULL, get next variable\r
      //\r
      Variable.CurrPtr = GetNextVariablePtr (Variable.CurrPtr);\r
    }\r
    //\r
    // If both volatile and non-volatile variable store are parsed,\r
    // return not found\r
    //\r
    if (Variable.CurrPtr >= Variable.EndPtr || Variable.CurrPtr == NULL) {\r
      Variable.Volatile = (BOOLEAN) (Variable.Volatile ^ ((BOOLEAN) 0x1));\r
      if (Variable.Volatile) {\r
        Variable.StartPtr = (VARIABLE_HEADER *) ((UINTN) (Global->VolatileVariableBase + sizeof (VARIABLE_STORE_HEADER)));\r
        Variable.EndPtr = (VARIABLE_HEADER *) GetEndPointer ((VARIABLE_STORE_HEADER *) ((UINTN) Global->VolatileVariableBase));\r
      } else {\r
        Status = EFI_NOT_FOUND;\r
        goto Done;\r
      }\r
\r
      Variable.CurrPtr = Variable.StartPtr;\r
      if (Variable.CurrPtr->StartId != VARIABLE_DATA) {\r
        continue;\r
      }\r
    }\r
    //\r
    // Variable is found\r
    //\r
    if (Variable.CurrPtr->StartId == VARIABLE_DATA && Variable.CurrPtr->State == VAR_ADDED) {\r
      if (!(EfiAtRuntime () && !(Variable.CurrPtr->Attributes & EFI_VARIABLE_RUNTIME_ACCESS))) {\r
        VarNameSize = Variable.CurrPtr->NameSize;\r
        if (VarNameSize <= *VariableNameSize) {\r
          CopyMem (\r
            VariableName,\r
            GET_VARIABLE_NAME_PTR (Variable.CurrPtr),\r
            VarNameSize\r
            );\r
          CopyMem (\r
            VendorGuid,\r
            &Variable.CurrPtr->VendorGuid,\r
            sizeof (EFI_GUID)\r
            );\r
          Status = EFI_SUCCESS;\r
        } else {\r
          Status = EFI_BUFFER_TOO_SMALL;\r
        }\r
\r
        *VariableNameSize = VarNameSize;\r
        goto Done;\r
      }\r
    }\r
  }\r
\r
Done:\r
  ReleaseLockOnlyAtBootTime (&Global->VariableServicesLock);\r
  return Status;\r
 \r
}\r
\r
EFI_STATUS\r
EFIAPI\r
SetVariable (\r
  IN CHAR16                  *VariableName,\r
  IN EFI_GUID                *VendorGuid,\r
  IN UINT32                  Attributes,\r
  IN UINTN                   DataSize,\r
  IN VOID                    *Data,\r
  IN VARIABLE_GLOBAL         *Global,\r
  IN UINTN                   *VolatileOffset,\r
  IN UINTN                   *NonVolatileOffset,\r
  IN UINT32                  Instance\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code sets variable in storage blocks (Volatile or Non-Volatile)\r
\r
Arguments:\r
\r
  VariableName                    Name of Variable to be found\r
  VendorGuid                      Variable vendor GUID\r
  Attributes                      Attribute value of the variable found\r
  DataSize                        Size of Data found. If size is less than the\r
                                  data, this value contains the required size.\r
  Data                            Data pointer\r
  Global                          Pointer to VARIABLE_GLOBAL structure\r
  VolatileOffset                  The offset of last volatile variable\r
  NonVolatileOffset               The offset of last non-volatile variable\r
  Instance                        Instance of the Firmware Volume.\r
\r
Returns:\r
\r
  EFI STATUS\r
\r
--*/\r
{\r
  VARIABLE_POINTER_TRACK  Variable;\r
  EFI_STATUS              Status;\r
  VARIABLE_HEADER         *NextVariable;\r
  UINTN                   VarNameSize;\r
  UINTN                   VarNameOffset;\r
  UINTN                   VarDataOffset;\r
  UINTN                   VarSize;\r
\r
  if (VariableName == NULL || VariableName[0] == 0 || VendorGuid == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  Status = FindVariable (VariableName, VendorGuid, &Variable, Global);\r
\r
  if (Status == EFI_INVALID_PARAMETER) {\r
    goto Done;\r
  } else if (!EFI_ERROR (Status) && Variable.Volatile && EfiAtRuntime()) {\r
    //\r
    // If EfiAtRuntime and the variable is Volatile and Runtime Access,  \r
    // the volatile is ReadOnly, and SetVariable should be aborted and \r
    // return EFI_WRITE_PROTECTED.\r
    //\r
    Status = EFI_WRITE_PROTECTED;\r
    goto Done;\r
  } else if (sizeof (VARIABLE_HEADER) + (ArrayLength (VariableName) + DataSize) > MAX_VARIABLE_SIZE) {\r
    //\r
    //  The size of the VariableName, including the Unicode Null in bytes plus\r
    //  the DataSize is limited to maximum size of MAX_VARIABLE_SIZE (1024) bytes.\r
    //\r
    Status = EFI_INVALID_PARAMETER;\r
    goto Done;\r
  } else if ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)) == EFI_VARIABLE_RUNTIME_ACCESS\r
          ) {\r
    //\r
    //  Make sure if runtime bit is set, boot service bit is set also\r
    //\r
    Status = EFI_INVALID_PARAMETER;\r
    goto Done;\r
  } else if (EfiAtRuntime () && Attributes && !(Attributes & EFI_VARIABLE_RUNTIME_ACCESS)) {\r
    //\r
    // Runtime but Attribute is not Runtime\r
    //\r
    Status = EFI_INVALID_PARAMETER;\r
    goto Done;\r
  } else if (EfiAtRuntime () && Attributes && !(Attributes & EFI_VARIABLE_NON_VOLATILE)) {\r
    //\r
    // Cannot set volatile variable in Runtime\r
    //\r
    Status = EFI_INVALID_PARAMETER;\r
    goto Done;\r
  } else if (DataSize == 0 || (Attributes & (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)) == 0) {\r
    //\r
    // Setting a data variable with no access, or zero DataSize attributes\r
    // specified causes it to be deleted.\r
    //\r
    if (!EFI_ERROR (Status)) {\r
      Variable.CurrPtr->State &= VAR_DELETED;\r
      Status = EFI_SUCCESS;\r
      goto Done;\r
    }\r
\r
    Status = EFI_NOT_FOUND;\r
    goto Done;\r
  } else {\r
    if (!EFI_ERROR (Status)) {\r
      //\r
      // If the variable is marked valid and the same data has been passed in\r
      // then return to the caller immediately.\r
      //\r
      if (Variable.CurrPtr->DataSize == DataSize &&\r
          !CompareMem (Data, GetVariableDataPtr (Variable.CurrPtr), DataSize)\r
            ) {\r
        Status = EFI_SUCCESS;\r
        goto Done;\r
      } else if (Variable.CurrPtr->State == VAR_ADDED) {\r
        //\r
        // Mark the old variable as in delete transition\r
        //\r
        Variable.CurrPtr->State &= VAR_IN_DELETED_TRANSITION;\r
      }\r
    }\r
    //\r
    // Create a new variable and copy the data.\r
    //\r
    VarNameOffset = sizeof (VARIABLE_HEADER);\r
    VarNameSize   = ArrayLength (VariableName);\r
    VarDataOffset = VarNameOffset + VarNameSize + GET_PAD_SIZE (VarNameSize);\r
    VarSize       = VarDataOffset + DataSize + GET_PAD_SIZE (DataSize);\r
\r
    if (Attributes & EFI_VARIABLE_NON_VOLATILE) {\r
      if ((UINT32) (VarSize +*NonVolatileOffset) >\r
            ((VARIABLE_STORE_HEADER *) ((UINTN) (Global->NonVolatileVariableBase)))->Size\r
            ) {\r
        Status = EFI_OUT_OF_RESOURCES;\r
        goto Done;\r
      }\r
\r
      NextVariable        = (VARIABLE_HEADER *) (UINT8 *) (*NonVolatileOffset + (UINTN) Global->NonVolatileVariableBase);\r
      *NonVolatileOffset  = *NonVolatileOffset + VarSize;\r
    } else {\r
      if (EfiAtRuntime ()) {\r
        Status = EFI_INVALID_PARAMETER;\r
        goto Done;\r
      }\r
\r
      if ((UINT32) (VarSize +*VolatileOffset) >\r
            ((VARIABLE_STORE_HEADER *) ((UINTN) (Global->VolatileVariableBase)))->Size\r
            ) {\r
        Status = EFI_OUT_OF_RESOURCES;\r
        goto Done;\r
      }\r
\r
      NextVariable    = (VARIABLE_HEADER *) (UINT8 *) (*VolatileOffset + (UINTN) Global->VolatileVariableBase);\r
      *VolatileOffset = *VolatileOffset + VarSize;\r
    }\r
\r
    NextVariable->StartId     = VARIABLE_DATA;\r
    NextVariable->Attributes  = Attributes;\r
    NextVariable->State       = VAR_ADDED;\r
    NextVariable->Reserved    = 0;\r
\r
    //\r
    // There will be pad bytes after Data, the NextVariable->NameSize and\r
    // NextVariable->NameSize should not include pad size so that variable\r
    // service can get actual size in GetVariable\r
    //\r
    NextVariable->NameSize  = (UINT32)VarNameSize;\r
    NextVariable->DataSize  = (UINT32)DataSize;\r
\r
    CopyMem (&NextVariable->VendorGuid, VendorGuid, sizeof (EFI_GUID));\r
    CopyMem (\r
      (UINT8 *) ((UINTN) NextVariable + VarNameOffset),\r
      VariableName,\r
      VarNameSize\r
      );\r
    CopyMem (\r
      (UINT8 *) ((UINTN) NextVariable + VarDataOffset),\r
      Data,\r
      DataSize\r
      );\r
\r
    //\r
    // Mark the old variable as deleted\r
    //\r
    if (!EFI_ERROR (Status)) {\r
      Variable.CurrPtr->State &= VAR_DELETED;\r
    }\r
  }\r
\r
  Status = EFI_SUCCESS;\r
Done:\r
  ReleaseLockOnlyAtBootTime (&Global->VariableServicesLock);\r
  return Status;\r
}\r
\r
#if (EFI_SPECIFICATION_VERSION >= 0x00020000)\r
EFI_STATUS\r
EFIAPI\r
QueryVariableInfo (\r
  IN  UINT32                 Attributes,\r
  OUT UINT64                 *MaximumVariableStorageSize,\r
  OUT UINT64                 *RemainingVariableStorageSize,\r
  OUT UINT64                 *MaximumVariableSize,\r
  IN  VARIABLE_GLOBAL        *Global,\r
  IN  UINT32                 Instance\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This code returns information about the EFI variables.\r
\r
Arguments:\r
\r
  Attributes                      Attributes bitmask to specify the type of variables\r
                                  on which to return information.\r
  MaximumVariableStorageSize      Pointer to the maximum size of the storage space available\r
                                  for the EFI variables associated with the attributes specified.\r
  RemainingVariableStorageSize    Pointer to the remaining size of the storage space available\r
                                  for the EFI variables associated with the attributes specified.\r
  MaximumVariableSize             Pointer to the maximum size of the individual EFI variables\r
                                  associated with the attributes specified.\r
  Global                          Pointer to VARIABLE_GLOBAL structure.\r
  Instance                        Instance of the Firmware Volume.\r
\r
Returns:\r
\r
  EFI STATUS\r
  EFI_INVALID_PARAMETER           - An invalid combination of attribute bits was supplied.\r
  EFI_SUCCESS                     - Query successfully.\r
  EFI_UNSUPPORTED                 - The attribute is not supported on this platform.\r
\r
--*/\r
{\r
  VARIABLE_HEADER        *Variable;\r
  VARIABLE_HEADER        *NextVariable;\r
  UINT64                 VariableSize;\r
  VARIABLE_STORE_HEADER  *VariableStoreHeader;\r
\r
  if(MaximumVariableStorageSize == NULL || RemainingVariableStorageSize == NULL || MaximumVariableSize == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if((Attributes & (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS)) == 0) {\r
    //\r
    // Make sure the Attributes combination is supported by the platform.\r
    //\r
    return EFI_UNSUPPORTED;\r
  } else if ((Attributes & (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS)) == EFI_VARIABLE_RUNTIME_ACCESS) {\r
    //\r
    // Make sure if runtime bit is set, boot service bit is set also.\r
    //\r
    return EFI_INVALID_PARAMETER;\r
  } else if (EfiAtRuntime () && !(Attributes & EFI_VARIABLE_RUNTIME_ACCESS)) {\r
    //\r
    //   Make sure RT Attribute is set if we are in Runtime phase.\r
    //\r
    return EFI_INVALID_PARAMETER;\r
  } else if (EfiAtRuntime () && Attributes && !(Attributes & EFI_VARIABLE_NON_VOLATILE)) {\r
    //\r
    // Cannot Query volatile variable in Runtime\r
    //\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  AcquireLockOnlyAtBootTime(&Global->VariableServicesLock);\r
  \r
  if((Attributes & EFI_VARIABLE_NON_VOLATILE) == 0) {\r
    //\r
    // Query is Volatile related.\r
    //\r
    VariableStoreHeader = (VARIABLE_STORE_HEADER *) ((UINTN) Global->VolatileVariableBase);\r
  } else {\r
    //\r
    // Query is Non-Volatile related.\r
    //\r
    VariableStoreHeader = (VARIABLE_STORE_HEADER *) ((UINTN) Global->NonVolatileVariableBase);\r
  }\r
\r
  //\r
  // Now let's fill *MaximumVariableStorageSize *RemainingVariableStorageSize\r
  // with the storage size (excluding the storage header size)\r
  //\r
  *MaximumVariableStorageSize   = VariableStoreHeader->Size - sizeof (VARIABLE_STORE_HEADER);\r
  *RemainingVariableStorageSize = VariableStoreHeader->Size - sizeof (VARIABLE_STORE_HEADER);\r
\r
  //\r
  // Let *MaximumVariableSize be MAX_VARIABLE_SIZE\r
  //\r
  *MaximumVariableSize = MAX_VARIABLE_SIZE;\r
\r
  //\r
  // Point to the starting address of the variables.\r
  //\r
  Variable = (VARIABLE_HEADER *) (VariableStoreHeader + 1);\r
\r
  //\r
  // Now walk through the related variable store.\r
  //\r
  while (Variable < GetEndPointer (VariableStoreHeader)) {\r
    if (Variable->StartId != VARIABLE_DATA) {\r
      break;\r
    }\r
\r
    NextVariable = (VARIABLE_HEADER *) (GetVariableDataPtr (Variable) + Variable->DataSize + GET_PAD_SIZE (Variable->DataSize));\r
    VariableSize = (UINT64) (UINTN) NextVariable - (UINT64) (UINTN) Variable;\r
\r
    if (Variable->State == VAR_ADDED) {\r
      *RemainingVariableStorageSize -= VariableSize;\r
    }\r
\r
    //\r
    // Go to the next one.\r
    //\r
    Variable = NextVariable;\r
  }\r
\r
  ReleaseLockOnlyAtBootTime (&Global->VariableServicesLock);\r
  return EFI_SUCCESS;\r
}\r
#endif\r
\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
InitializeVariableStore (\r
  OUT EFI_PHYSICAL_ADDRESS  *VariableBase,\r
  OUT UINTN                 *LastVariableOffset\r
  )\r
/*++\r
\r
Routine Description:\r
  This function initializes variable store\r
\r
Arguments:\r
\r
Returns:\r
\r
--*/\r
{\r
  VARIABLE_STORE_HEADER *VariableStore;\r
\r
  //\r
  // Allocate memory for volatile variable store\r
  //\r
  VariableStore = (VARIABLE_STORE_HEADER *) AllocateRuntimePool (\r
                                              VARIABLE_STORE_SIZE\r
                                              );\r
  if (NULL == VariableStore) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  SetMem (VariableStore, VARIABLE_STORE_SIZE, 0xff);\r
\r
  //\r
  // Variable Specific Data\r
  //\r
  *VariableBase             = (EFI_PHYSICAL_ADDRESS) (UINTN) VariableStore;\r
  *LastVariableOffset       = sizeof (VARIABLE_STORE_HEADER);\r
\r
  VariableStore->Signature  = VARIABLE_STORE_SIGNATURE;\r
  VariableStore->Size       = VARIABLE_STORE_SIZE;\r
  VariableStore->Format     = VARIABLE_STORE_FORMATTED;\r
  VariableStore->State      = VARIABLE_STORE_HEALTHY;\r
  VariableStore->Reserved   = 0;\r
  VariableStore->Reserved1  = 0;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
VariableCommonInitialize (\r
  IN EFI_HANDLE         ImageHandle,\r
  IN EFI_SYSTEM_TABLE   *SystemTable\r
  )\r
/*++\r
\r
Routine Description:\r
  This function does common initialization for variable services\r
\r
Arguments:\r
\r
Returns:\r
\r
--*/\r
{\r
  EFI_STATUS  Status;\r
\r
  //\r
  // Allocate memory for mVariableModuleGlobal\r
  //\r
  mVariableModuleGlobal = (ESAL_VARIABLE_GLOBAL *) AllocateRuntimePool (\r
                                                    sizeof (ESAL_VARIABLE_GLOBAL)\r
                                                   );\r
  if (NULL == mVariableModuleGlobal) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  EfiInitializeLock(&mVariableModuleGlobal->VariableGlobal[Physical].VariableServicesLock, EFI_TPL_CALLBACK);\r
  \r
  //\r
  // Intialize volatile variable store\r
  //\r
  Status = InitializeVariableStore (\r
            &mVariableModuleGlobal->VariableGlobal[Physical].VolatileVariableBase,\r
            &mVariableModuleGlobal->VolatileLastVariableOffset\r
            );\r
\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
  //\r
  // Intialize non volatile variable store\r
  //\r
  Status = InitializeVariableStore (\r
            &mVariableModuleGlobal->VariableGlobal[Physical].NonVolatileVariableBase,\r
            &mVariableModuleGlobal->NonVolatileLastVariableOffset\r
            );\r
\r
  return Status;\r
}\r