MdeModulePkg/Universal/FaultTolerantWriteDxe/FaultTolerantWriteDxe.c

   1 /** @file
   2
   3   This is a simple fault tolerant write driver.
   4
   5   This boot service protocol only provides fault tolerant write capability for
   6   block devices.  The protocol has internal non-volatile intermediate storage
   7   of the data and private information. It should be able to recover
   8   automatically from a critical fault, such as power failure.
   9
  10   The implementation uses an FTW (Fault Tolerant Write) Work Space.
  11   This work space is a memory copy of the work space on the Working Block,
  12   the size of the work space is the FTW_WORK_SPACE_SIZE bytes.
  13
  14   The work space stores each write record as EFI_FTW_RECORD structure.
  15   The spare block stores the write buffer before write to the target block.
  16
  17   The write record has three states to specify the different phase of write operation.
  18   1) WRITE_ALLOCATED is that the record is allocated in write space.
  19      The information of write operation is stored in write record structure.
  20   2) SPARE_COMPLETED is that the data from write buffer is writed into the spare block as the backup.
  21   3) WRITE_COMPLETED is that the data is copied from the spare block to the target block.
  22
  23   This driver operates the data as the whole size of spare block.
  24   It first read the SpareAreaLength data from the target block into the spare memory buffer.
  25   Then copy the write buffer data into the spare memory buffer.
  26   Then write the spare memory buffer into the spare block.
  27   Final copy the data from the spare block to the target block.
  28
  29   To make this drive work well, the following conditions must be satisfied:
  30   1. The write NumBytes data must be fit within Spare area.
  31      Offset + NumBytes <= SpareAreaLength
  32   2. The whole flash range has the same block size.
  33   3. Working block is an area which contains working space in its last block and has the same size as spare block.
  34   4. Working Block area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
  35   5. Spare area must be in the single one Firmware Volume Block range which FVB protocol is produced on.
  36   6. Any write data area (SpareAreaLength Area) which the data will be written into must be
  37      in the single one Firmware Volume Block range which FVB protocol is produced on.
  38   7. If write data area (such as Variable range) is enlarged, the spare area range must be enlarged.
  39      The spare area must be enough large to store the write data before write them into the target range.
  40   If one of them is not satisfied, FtwWrite may fail.
  41   Usually, Spare area only takes one block. That's SpareAreaLength = BlockSize, NumberOfSpareBlock = 1.
  42
  43 Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
  44 SPDX-License-Identifier: BSD-2-Clause-Patent
  45
  46 **/
  47
  48 #include <Library/UefiBootServicesTableLib.h>
  49 #include "FaultTolerantWrite.h"
  50 VOID  *mFvbRegistration = NULL;
  51
  52 /**
  53   Retrieve the FVB protocol interface by HANDLE.
  54
  55   @param[in]  FvBlockHandle     The handle of FVB protocol that provides services for
  56                                 reading, writing, and erasing the target block.
  57   @param[out] FvBlock           The interface of FVB protocol
  58
  59   @retval EFI_SUCCESS           The interface information for the specified protocol was returned.
  60   @retval EFI_UNSUPPORTED       The device does not support the FVB protocol.
  61   @retval EFI_INVALID_PARAMETER FvBlockHandle is not a valid EFI_HANDLE or FvBlock is NULL.
  62
  63 **/
  64 EFI_STATUS
  65 FtwGetFvbByHandle (
  66   IN  EFI_HANDLE                          FvBlockHandle,
  67   OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvBlock
  68   )
  69 {
  70   //
  71   // To get the FVB protocol interface on the handle
  72   //
  73   return gBS->HandleProtocol (
  74                 FvBlockHandle,
  75                 &gEfiFirmwareVolumeBlockProtocolGuid,
  76                 (VOID **)FvBlock
  77                 );
  78 }
  79
  80 /**
  81   Retrieve the Swap Address Range protocol interface.
  82
  83   @param[out] SarProtocol       The interface of SAR protocol
  84
  85   @retval EFI_SUCCESS           The SAR protocol instance was found and returned in SarProtocol.
  86   @retval EFI_NOT_FOUND         The SAR protocol instance was not found.
  87   @retval EFI_INVALID_PARAMETER SarProtocol is NULL.
  88
  89 **/
  90 EFI_STATUS
  91 FtwGetSarProtocol (
  92   OUT VOID  **SarProtocol
  93   )
  94 {
  95   EFI_STATUS  Status;
  96
  97   //
  98   // Locate Swap Address Range protocol
  99   //
 100   Status = gBS->LocateProtocol (
 101                   &gEfiSwapAddressRangeProtocolGuid,
 102                   NULL,
 103                   SarProtocol
 104                   );
 105   return Status;
 106 }
 107
 108 /**
 109   Function returns an array of handles that support the FVB protocol
 110   in a buffer allocated from pool.
 111
 112   @param[out]  NumberHandles    The number of handles returned in Buffer.
 113   @param[out]  Buffer           A pointer to the buffer to return the requested
 114                                 array of  handles that support FVB protocol.
 115
 116   @retval EFI_SUCCESS           The array of handles was returned in Buffer, and the number of
 117                                 handles in Buffer was returned in NumberHandles.
 118   @retval EFI_NOT_FOUND         No FVB handle was found.
 119   @retval EFI_OUT_OF_RESOURCES  There is not enough pool memory to store the matching results.
 120   @retval EFI_INVALID_PARAMETER NumberHandles is NULL or Buffer is NULL.
 121
 122 **/
 123 EFI_STATUS
 124 GetFvbCountAndBuffer (
 125   OUT UINTN       *NumberHandles,
 126   OUT EFI_HANDLE  **Buffer
 127   )
 128 {
 129   EFI_STATUS  Status;
 130
 131   //
 132   // Locate all handles of Fvb protocol
 133   //
 134   Status = gBS->LocateHandleBuffer (
 135                   ByProtocol,
 136                   &gEfiFirmwareVolumeBlockProtocolGuid,
 137                   NULL,
 138                   NumberHandles,
 139                   Buffer
 140                   );
 141   return Status;
 142 }
 143
 144 /**
 145   Firmware Volume Block Protocol notification event handler.
 146
 147   @param[in] Event    Event whose notification function is being invoked.
 148   @param[in] Context  Pointer to the notification function's context.
 149
 150 **/
 151 VOID
 152 EFIAPI
 153 FvbNotificationEvent (
 154   IN  EFI_EVENT  Event,
 155   IN  VOID       *Context
 156   )
 157 {
 158   EFI_STATUS                         Status;
 159   EFI_FAULT_TOLERANT_WRITE_PROTOCOL  *FtwProtocol;
 160   EFI_FTW_DEVICE                     *FtwDevice;
 161
 162   //
 163   // Just return to avoid installing FaultTolerantWriteProtocol again
 164   // if Fault Tolerant Write protocol has been installed.
 165   //
 166   Status = gBS->LocateProtocol (
 167                   &gEfiFaultTolerantWriteProtocolGuid,
 168                   NULL,
 169                   (VOID **)&FtwProtocol
 170                   );
 171   if (!EFI_ERROR (Status)) {
 172     return;
 173   }
 174
 175   //
 176   // Found proper FVB protocol and initialize FtwDevice for protocol installation
 177   //
 178   FtwDevice = (EFI_FTW_DEVICE *)Context;
 179   Status    = InitFtwProtocol (FtwDevice);
 180   if (EFI_ERROR (Status)) {
 181     return;
 182   }
 183
 184   //
 185   // Install protocol interface
 186   //
 187   Status = gBS->InstallProtocolInterface (
 188                   &FtwDevice->Handle,
 189                   &gEfiFaultTolerantWriteProtocolGuid,
 190                   EFI_NATIVE_INTERFACE,
 191                   &FtwDevice->FtwInstance
 192                   );
 193   ASSERT_EFI_ERROR (Status);
 194
 195   Status = gBS->CloseEvent (Event);
 196   ASSERT_EFI_ERROR (Status);
 197
 198   return;
 199 }
 200
 201 /**
 202   This function is the entry point of the Fault Tolerant Write driver.
 203
 204   @param[in] ImageHandle        A handle for the image that is initializing this driver
 205   @param[in] SystemTable        A pointer to the EFI system table
 206
 207   @retval EFI_SUCCESS           The initialization finished successfully.
 208   @retval EFI_OUT_OF_RESOURCES  Allocate memory error
 209   @retval EFI_INVALID_PARAMETER Workspace or Spare block does not exist
 210
 211 **/
 212 EFI_STATUS
 213 EFIAPI
 214 FaultTolerantWriteInitialize (
 215   IN EFI_HANDLE        ImageHandle,
 216   IN EFI_SYSTEM_TABLE  *SystemTable
 217   )
 218 {
 219   EFI_STATUS      Status;
 220   EFI_FTW_DEVICE  *FtwDevice;
 221
 222   FtwDevice = NULL;
 223
 224   //
 225   // Allocate private data structure for FTW protocol and do some initialization
 226   //
 227   Status = InitFtwDevice (&FtwDevice);
 228   if (EFI_ERROR (Status)) {
 229     return Status;
 230   }
 231
 232   //
 233   // Register FvbNotificationEvent () notify function.
 234   //
 235   EfiCreateProtocolNotifyEvent (
 236     &gEfiFirmwareVolumeBlockProtocolGuid,
 237     TPL_CALLBACK,
 238     FvbNotificationEvent,
 239     (VOID *)FtwDevice,
 240     &mFvbRegistration
 241     );
 242
 243   return EFI_SUCCESS;
 244 }
 245
 246 /**
 247   Internal implementation of CRC32. Depending on the execution context
 248   (traditional SMM or DXE vs standalone MM), this function is implemented
 249   via a call to the CalculateCrc32 () boot service, or via a library
 250   call.
 251
 252   If Buffer is NULL, then ASSERT().
 253   If Length is greater than (MAX_ADDRESS - Buffer + 1), then ASSERT().
 254
 255   @param[in]  Buffer       A pointer to the buffer on which the 32-bit CRC is to be computed.
 256   @param[in]  Length       The number of bytes in the buffer Data.
 257
 258   @retval Crc32            The 32-bit CRC was computed for the data buffer.
 259
 260 **/
 261 UINT32
 262 FtwCalculateCrc32 (
 263   IN  VOID   *Buffer,
 264   IN  UINTN  Length
 265   )
 266 {
 267   EFI_STATUS  Status;
 268   UINT32      ReturnValue;
 269
 270   Status = gBS->CalculateCrc32 (Buffer, Length, &ReturnValue);
 271   ASSERT_EFI_ERROR (Status);
 272
 273   return ReturnValue;
 274 }