[mirror_edk2.git] / OvmfPkg / XenPvBlkDxe / BlockIo.c

/** @file\r
  BlockIo implementation for Xen PV Block driver.\r
\r
  This file is implementing the interface between the actual driver in\r
  BlockFront.c to the BlockIo protocol.\r
\r
  Copyright (C) 2014, Citrix Ltd.\r
\r
  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
**/\r
\r
#include "XenPvBlkDxe.h"\r
\r
#include "BlockFront.h"\r
\r
///\r
/// Block I/O Media structure\r
///\r
GLOBAL_REMOVE_IF_UNREFERENCED\r
EFI_BLOCK_IO_MEDIA  gXenPvBlkDxeBlockIoMedia = {\r
  0,      // MediaId\r
  FALSE,  // RemovableMedia\r
  FALSE,  // MediaPresent\r
  FALSE,  // LogicalPartition\r
  TRUE,   // ReadOnly\r
  FALSE,  // WriteCaching\r
  512,    // BlockSize\r
  512,    // IoAlign, BlockFront does not support less than 512 bits-aligned.\r
  0,      // LastBlock\r
  0,      // LowestAlignedLba\r
  0,      // LogicalBlocksPerPhysicalBlock\r
  0       // OptimalTransferLengthGranularity\r
};\r
\r
///\r
/// Block I/O Protocol instance\r
///\r
GLOBAL_REMOVE_IF_UNREFERENCED\r
EFI_BLOCK_IO_PROTOCOL  gXenPvBlkDxeBlockIo = {\r
  EFI_BLOCK_IO_PROTOCOL_REVISION3,          // Revision\r
  &gXenPvBlkDxeBlockIoMedia,                // Media\r
  XenPvBlkDxeBlockIoReset,                  // Reset\r
  XenPvBlkDxeBlockIoReadBlocks,             // ReadBlocks\r
  XenPvBlkDxeBlockIoWriteBlocks,            // WriteBlocks\r
  XenPvBlkDxeBlockIoFlushBlocks             // FlushBlocks\r
};\r
\r
\r
\r
\r
/**\r
  Read/Write BufferSize bytes from Lba into Buffer.\r
\r
  This function is commun to XenPvBlkDxeBlockIoReadBlocks and\r
  XenPvBlkDxeBlockIoWriteBlocks.\r
\r
  @param  This       Indicates a pointer to the calling context.\r
  @param  MediaId    Id of the media, changes every time the media is replaced.\r
  @param  Lba        The starting Logical Block Address to read from/write to.\r
  @param  BufferSize Size of Buffer, must be a multiple of device block size.\r
  @param  Buffer     A pointer to the destination/source buffer for the data.\r
  @param  IsWrite    Indicate if the operation is write or read.\r
\r
  @return See description of XenPvBlkDxeBlockIoReadBlocks and\r
          XenPvBlkDxeBlockIoWriteBlocks.\r
**/\r
STATIC\r
EFI_STATUS\r
XenPvBlkDxeBlockIoReadWriteBlocks (\r
  IN     EFI_BLOCK_IO_PROTOCOL  *This,\r
  IN     UINT32                 MediaId,\r
  IN     EFI_LBA                Lba,\r
  IN     UINTN                  BufferSize,\r
  IN OUT VOID                   *Buffer,\r
  IN     BOOLEAN                IsWrite\r
  )\r
{\r
  XEN_BLOCK_FRONT_IO IoData;\r
  EFI_BLOCK_IO_MEDIA *Media = This->Media;\r
  UINTN Sector;\r
  EFI_STATUS Status;\r
\r
  if (Buffer == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
  if (BufferSize == 0) {\r
    return EFI_SUCCESS;\r
  }\r
\r
  if (BufferSize % Media->BlockSize != 0) {\r
    DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Bad buffer size: 0x%Lx\n",\r
      (UINT64)BufferSize));\r
    return EFI_BAD_BUFFER_SIZE;\r
  }\r
\r
  if (Lba > Media->LastBlock ||\r
      (BufferSize / Media->BlockSize) - 1 > Media->LastBlock - Lba) {\r
    DEBUG ((EFI_D_ERROR,\r
      "XenPvBlkDxe: %a with invalid LBA: 0x%Lx, size: 0x%Lx\n",\r
      IsWrite ? "Write" : "Read", Lba, (UINT64)BufferSize));\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (IsWrite && Media->ReadOnly) {\r
    return EFI_WRITE_PROTECTED;\r
  }\r
\r
  if ((Media->IoAlign > 1) && (UINTN)Buffer & (Media->IoAlign - 1)) {\r
    //\r
    // Grub2 does not appear to respect IoAlign of 512, so reallocate the\r
    // buffer here.\r
    //\r
    VOID *NewBuffer;\r
\r
    //\r
    // Try again with a properly aligned buffer.\r
    //\r
    NewBuffer = AllocateAlignedPages((BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE,\r
                                     Media->IoAlign);\r
    if (!IsWrite) {\r
      Status = XenPvBlkDxeBlockIoReadBlocks (This, MediaId,\r
                                             Lba, BufferSize, NewBuffer);\r
      CopyMem (Buffer, NewBuffer, BufferSize);\r
    } else {\r
      CopyMem (NewBuffer, Buffer, BufferSize);\r
      Status = XenPvBlkDxeBlockIoWriteBlocks (This, MediaId,\r
                                              Lba, BufferSize, NewBuffer);\r
    }\r
    FreeAlignedPages (NewBuffer, (BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE);\r
    return Status;\r
  }\r
\r
  IoData.Dev = XEN_BLOCK_FRONT_FROM_BLOCK_IO (This);\r
  Sector = (UINTN)MultU64x32 (Lba, Media->BlockSize / 512);\r
\r
  while (BufferSize > 0) {\r
    if (((UINTN)Buffer & EFI_PAGE_MASK) == 0) {\r
      IoData.Size = MIN (BLKIF_MAX_SEGMENTS_PER_REQUEST * EFI_PAGE_SIZE,\r
                         BufferSize);\r
    } else {\r
      IoData.Size = MIN ((BLKIF_MAX_SEGMENTS_PER_REQUEST - 1) * EFI_PAGE_SIZE,\r
                         BufferSize);\r
    }\r
\r
    IoData.Buffer = Buffer;\r
    IoData.Sector = Sector;\r
    BufferSize -= IoData.Size;\r
    Buffer = (VOID*) ((UINTN) Buffer + IoData.Size);\r
    Sector += IoData.Size / 512;\r
    Status = XenPvBlockIo (&IoData, IsWrite);\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Error during %a operation.\n",\r
              IsWrite ? "write" : "read"));\r
      return Status;\r
    }\r
  }\r
  return EFI_SUCCESS;\r
}\r
\r
\r
/**\r
  Read BufferSize bytes from Lba into Buffer.\r
\r
  @param  This       Indicates a pointer to the calling context.\r
  @param  MediaId    Id of the media, changes every time the media is replaced.\r
  @param  Lba        The starting Logical Block Address to read from\r
  @param  BufferSize Size of Buffer, must be a multiple of device block size.\r
  @param  Buffer     A pointer to the destination buffer for the data. The caller is\r
                     responsible for either having implicit or explicit ownership of the buffer.\r
\r
  @retval EFI_SUCCESS           The data was read correctly from the device.\r
  @retval EFI_DEVICE_ERROR      The device reported an error while performing the read.\r
  @retval EFI_NO_MEDIA          There is no media in the device.\r
  @retval EFI_MEDIA_CHANGED     The MediaId does not matched the current device.\r
  @retval EFI_BAD_BUFFER_SIZE   The Buffer was not a multiple of the block size of the device.\r
  @retval EFI_INVALID_PARAMETER The read request contains LBAs that are not valid,\r
                                or the buffer is not on proper alignment.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
XenPvBlkDxeBlockIoReadBlocks (\r
  IN  EFI_BLOCK_IO_PROTOCOL         *This,\r
  IN  UINT32                        MediaId,\r
  IN  EFI_LBA                       Lba,\r
  IN  UINTN                         BufferSize,\r
  OUT VOID                          *Buffer\r
  )\r
{\r
  return XenPvBlkDxeBlockIoReadWriteBlocks (This,\r
      MediaId, Lba, BufferSize, Buffer, FALSE);\r
}\r
\r
/**\r
  Write BufferSize bytes from Lba into Buffer.\r
\r
  @param  This       Indicates a pointer to the calling context.\r
  @param  MediaId    The media ID that the write request is for.\r
  @param  Lba        The starting logical block address to be written. The caller is\r
                     responsible for writing to only legitimate locations.\r
  @param  BufferSize Size of Buffer, must be a multiple of device block size.\r
  @param  Buffer     A pointer to the source buffer for the data.\r
\r
  @retval EFI_SUCCESS           The data was written correctly to the device.\r
  @retval EFI_WRITE_PROTECTED   The device can not be written to.\r
  @retval EFI_DEVICE_ERROR      The device reported an error while performing the write.\r
  @retval EFI_NO_MEDIA          There is no media in the device.\r
  @retval EFI_MEDIA_CHNAGED     The MediaId does not matched the current device.\r
  @retval EFI_BAD_BUFFER_SIZE   The Buffer was not a multiple of the block size of the device.\r
  @retval EFI_INVALID_PARAMETER The write request contains LBAs that are not valid,\r
                                or the buffer is not on proper alignment.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
XenPvBlkDxeBlockIoWriteBlocks (\r
  IN EFI_BLOCK_IO_PROTOCOL          *This,\r
  IN UINT32                         MediaId,\r
  IN EFI_LBA                        Lba,\r
  IN UINTN                          BufferSize,\r
  IN VOID                           *Buffer\r
  )\r
{\r
  return XenPvBlkDxeBlockIoReadWriteBlocks (This,\r
      MediaId, Lba, BufferSize, Buffer, TRUE);\r
}\r
\r
/**\r
  Flush the Block Device.\r
\r
  @param  This              Indicates a pointer to the calling context.\r
\r
  @retval EFI_SUCCESS       All outstanding data was written to the device\r
  @retval EFI_DEVICE_ERROR  The device reported an error while writting back the data\r
  @retval EFI_NO_MEDIA      There is no media in the device.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
XenPvBlkDxeBlockIoFlushBlocks (\r
  IN EFI_BLOCK_IO_PROTOCOL  *This\r
  )\r
{\r
  XenPvBlockSync (XEN_BLOCK_FRONT_FROM_BLOCK_IO (This));\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Reset the block device hardware.\r
\r
  @param[in]  This                 Indicates a pointer to the calling context.\r
  @param[in]  ExtendedVerification Not used.\r
\r
  @retval EFI_SUCCESS          The device was reset.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
XenPvBlkDxeBlockIoReset (\r
  IN EFI_BLOCK_IO_PROTOCOL   *This,\r
  IN BOOLEAN                 ExtendedVerification\r
  )\r
{\r
  //\r
  // Since the initialization of the devices is done, then the device is\r
  // working correctly.\r
  //\r
  return EFI_SUCCESS;\r
}\r
Commit	Line	Data
5de8a35c AP	1	/** @file\r
	2	BlockIo implementation for Xen PV Block driver.\r
	3	\r
	4	This file is implementing the interface between the actual driver in\r
	5	BlockFront.c to the BlockIo protocol.\r
	6	\r
	7	Copyright (C) 2014, Citrix Ltd.\r
	8	\r
	9	This program and the accompanying materials\r
	10	are licensed and made available under the terms and conditions of the BSD License\r
	11	which accompanies this distribution. The full text of the license may be found at\r
	12	http://opensource.org/licenses/bsd-license.php\r
	13	\r
	14	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	15	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	16	\r
	17	**/\r
	18	\r
	19	#include "XenPvBlkDxe.h"\r
	20	\r
	21	#include "BlockFront.h"\r
	22	\r
	23	///\r
	24	/// Block I/O Media structure\r
	25	///\r
	26	GLOBAL_REMOVE_IF_UNREFERENCED\r
	27	EFI_BLOCK_IO_MEDIA gXenPvBlkDxeBlockIoMedia = {\r
	28	0, // MediaId\r
	29	FALSE, // RemovableMedia\r
	30	FALSE, // MediaPresent\r
	31	FALSE, // LogicalPartition\r
	32	TRUE, // ReadOnly\r
	33	FALSE, // WriteCaching\r
	34	512, // BlockSize\r
	35	512, // IoAlign, BlockFront does not support less than 512 bits-aligned.\r
	36	0, // LastBlock\r
	37	0, // LowestAlignedLba\r
	38	0, // LogicalBlocksPerPhysicalBlock\r
	39	0 // OptimalTransferLengthGranularity\r
	40	};\r
	41	\r
	42	///\r
	43	/// Block I/O Protocol instance\r
	44	///\r
	45	GLOBAL_REMOVE_IF_UNREFERENCED\r
	46	EFI_BLOCK_IO_PROTOCOL gXenPvBlkDxeBlockIo = {\r
	47	EFI_BLOCK_IO_PROTOCOL_REVISION3, // Revision\r
	48	&gXenPvBlkDxeBlockIoMedia, // Media\r
	49	XenPvBlkDxeBlockIoReset, // Reset\r
	50	XenPvBlkDxeBlockIoReadBlocks, // ReadBlocks\r
	51	XenPvBlkDxeBlockIoWriteBlocks, // WriteBlocks\r
	52	XenPvBlkDxeBlockIoFlushBlocks // FlushBlocks\r
	53	};\r
	54	\r
	55	\r
	56	\r
	57	\r
	58	/**\r
	59	Read/Write BufferSize bytes from Lba into Buffer.\r
	60	\r
	61	This function is commun to XenPvBlkDxeBlockIoReadBlocks and\r
	62	XenPvBlkDxeBlockIoWriteBlocks.\r
	63	\r
	64	@param This Indicates a pointer to the calling context.\r
65	@param MediaId Id of the media, changes every time the media is replaced.\r
66	@param Lba The starting Logical Block Address to read from/write to.\r
67	@param BufferSize Size of Buffer, must be a multiple of device block size.\r
68	@param Buffer A pointer to the destination/source buffer for the data.\r
69	@param IsWrite Indicate if the operation is write or read.\r
70	\r
71	@return See description of XenPvBlkDxeBlockIoReadBlocks and\r
72	XenPvBlkDxeBlockIoWriteBlocks.\r
73	**/\r
74	STATIC\r
75	EFI_STATUS\r
76	XenPvBlkDxeBlockIoReadWriteBlocks (\r
77	IN EFI_BLOCK_IO_PROTOCOL *This,\r
78	IN UINT32 MediaId,\r
79	IN EFI_LBA Lba,\r
80	IN UINTN BufferSize,\r
81	IN OUT VOID *Buffer,\r
82	IN BOOLEAN IsWrite\r
83	)\r
84	{\r
85	XEN_BLOCK_FRONT_IO IoData;\r
86	EFI_BLOCK_IO_MEDIA *Media = This->Media;\r
87	UINTN Sector;\r
88	EFI_STATUS Status;\r
89	\r
90	if (Buffer == NULL) {\r
91	return EFI_INVALID_PARAMETER;\r
92	}\r
93	if (BufferSize == 0) {\r
94	return EFI_SUCCESS;\r
95	}\r
96	\r
97	if (BufferSize % Media->BlockSize != 0) {\r
6394c35a LE	98	DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Bad buffer size: 0x%Lx\n",\r
6394c35a LE	99	(UINT64)BufferSize));\r
5de8a35c AP	100	return EFI_BAD_BUFFER_SIZE;\r
	101	}\r
	102	\r
	103	if (Lba > Media->LastBlock \|\|\r
	104	(BufferSize / Media->BlockSize) - 1 > Media->LastBlock - Lba) {\r
6394c35a LE	105	DEBUG ((EFI_D_ERROR,\r
	106	"XenPvBlkDxe: %a with invalid LBA: 0x%Lx, size: 0x%Lx\n",\r
	107	IsWrite ? "Write" : "Read", Lba, (UINT64)BufferSize));\r
5de8a35c AP	108	return EFI_INVALID_PARAMETER;\r
	109	}\r
	110	\r
	111	if (IsWrite && Media->ReadOnly) {\r
	112	return EFI_WRITE_PROTECTED;\r
	113	}\r
	114	\r
	115	if ((Media->IoAlign > 1) && (UINTN)Buffer & (Media->IoAlign - 1)) {\r
	116	//\r
	117	// Grub2 does not appear to respect IoAlign of 512, so reallocate the\r
	118	// buffer here.\r
	119	//\r
	120	VOID *NewBuffer;\r
	121	\r
	122	//\r
	123	// Try again with a properly aligned buffer.\r
	124	//\r
	125	NewBuffer = AllocateAlignedPages((BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE,\r
	126	Media->IoAlign);\r
	127	if (!IsWrite) {\r
	128	Status = XenPvBlkDxeBlockIoReadBlocks (This, MediaId,\r
	129	Lba, BufferSize, NewBuffer);\r
	130	CopyMem (Buffer, NewBuffer, BufferSize);\r
	131	} else {\r
	132	CopyMem (NewBuffer, Buffer, BufferSize);\r
	133	Status = XenPvBlkDxeBlockIoWriteBlocks (This, MediaId,\r
	134	Lba, BufferSize, NewBuffer);\r
	135	}\r
	136	FreeAlignedPages (NewBuffer, (BufferSize + EFI_PAGE_SIZE) / EFI_PAGE_SIZE);\r
	137	return Status;\r
	138	}\r
	139	\r
	140	IoData.Dev = XEN_BLOCK_FRONT_FROM_BLOCK_IO (This);\r
860088f2	141	Sector = (UINTN)MultU64x32 (Lba, Media->BlockSize / 512);\r
5de8a35c AP	142	\r
	143	while (BufferSize > 0) {\r
	144	if (((UINTN)Buffer & EFI_PAGE_MASK) == 0) {\r
	145	IoData.Size = MIN (BLKIF_MAX_SEGMENTS_PER_REQUEST * EFI_PAGE_SIZE,\r
	146	BufferSize);\r
	147	} else {\r
	148	IoData.Size = MIN ((BLKIF_MAX_SEGMENTS_PER_REQUEST - 1) * EFI_PAGE_SIZE,\r
	149	BufferSize);\r
	150	}\r
	151	\r
	152	IoData.Buffer = Buffer;\r
	153	IoData.Sector = Sector;\r
	154	BufferSize -= IoData.Size;\r
	155	Buffer = (VOID*) ((UINTN) Buffer + IoData.Size);\r
	156	Sector += IoData.Size / 512;\r
	157	Status = XenPvBlockIo (&IoData, IsWrite);\r
	158	if (EFI_ERROR (Status)) {\r
8c0b0b34	159	DEBUG ((EFI_D_ERROR, "XenPvBlkDxe: Error during %a operation.\n",\r
5de8a35c AP	160	IsWrite ? "write" : "read"));\r
	161	return Status;\r
	162	}\r
	163	}\r
	164	return EFI_SUCCESS;\r
	165	}\r
	166	\r
	167	\r
	168	/**\r
	169	Read BufferSize bytes from Lba into Buffer.\r
	170	\r
	171	@param This Indicates a pointer to the calling context.\r
	172	@param MediaId Id of the media, changes every time the media is replaced.\r
	173	@param Lba The starting Logical Block Address to read from\r
	174	@param BufferSize Size of Buffer, must be a multiple of device block size.\r
	175	@param Buffer A pointer to the destination buffer for the data. The caller is\r
	176	responsible for either having implicit or explicit ownership of the buffer.\r
	177	\r
	178	@retval EFI_SUCCESS The data was read correctly from the device.\r
	179	@retval EFI_DEVICE_ERROR The device reported an error while performing the read.\r
	180	@retval EFI_NO_MEDIA There is no media in the device.\r
	181	@retval EFI_MEDIA_CHANGED The MediaId does not matched the current device.\r
	182	@retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block size of the device.\r
	183	@retval EFI_INVALID_PARAMETER The read request contains LBAs that are not valid,\r
	184	or the buffer is not on proper alignment.\r
	185	\r
	186	**/\r
	187	EFI_STATUS\r
	188	EFIAPI\r
	189	XenPvBlkDxeBlockIoReadBlocks (\r
	190	IN EFI_BLOCK_IO_PROTOCOL *This,\r
	191	IN UINT32 MediaId,\r
	192	IN EFI_LBA Lba,\r
	193	IN UINTN BufferSize,\r
	194	OUT VOID *Buffer\r
	195	)\r
	196	{\r
	197	return XenPvBlkDxeBlockIoReadWriteBlocks (This,\r
	198	MediaId, Lba, BufferSize, Buffer, FALSE);\r
	199	}\r
	200	\r
	201	/**\r
	202	Write BufferSize bytes from Lba into Buffer.\r
	203	\r
	204	@param This Indicates a pointer to the calling context.\r
	205	@param MediaId The media ID that the write request is for.\r
	206	@param Lba The starting logical block address to be written. The caller is\r
	207	responsible for writing to only legitimate locations.\r
	208	@param BufferSize Size of Buffer, must be a multiple of device block size.\r
	209	@param Buffer A pointer to the source buffer for the data.\r
	210	\r
	211	@retval EFI_SUCCESS The data was written correctly to the device.\r
	212	@retval EFI_WRITE_PROTECTED The device can not be written to.\r
	213	@retval EFI_DEVICE_ERROR The device reported an error while performing the write.\r
	214	@retval EFI_NO_MEDIA There is no media in the device.\r
	215	@retval EFI_MEDIA_CHNAGED The MediaId does not matched the current device.\r
	216	@retval EFI_BAD_BUFFER_SIZE The Buffer was not a multiple of the block size of the device.\r
	217	@retval EFI_INVALID_PARAMETER The write request contains LBAs that are not valid,\r
	218	or the buffer is not on proper alignment.\r
	219	\r
	220	**/\r
	221	EFI_STATUS\r
	222	EFIAPI\r
	223	XenPvBlkDxeBlockIoWriteBlocks (\r
224	IN EFI_BLOCK_IO_PROTOCOL *This,\r
225	IN UINT32 MediaId,\r
226	IN EFI_LBA Lba,\r
227	IN UINTN BufferSize,\r
228	IN VOID *Buffer\r
229	)\r
230	{\r
231	return XenPvBlkDxeBlockIoReadWriteBlocks (This,\r
232	MediaId, Lba, BufferSize, Buffer, TRUE);\r
233	}\r
234	\r
235	/**\r
236	Flush the Block Device.\r
237	\r
238	@param This Indicates a pointer to the calling context.\r
239	\r
240	@retval EFI_SUCCESS All outstanding data was written to the device\r
241	@retval EFI_DEVICE_ERROR The device reported an error while writting back the data\r
242	@retval EFI_NO_MEDIA There is no media in the device.\r
243	\r
244	**/\r
245	EFI_STATUS\r
246	EFIAPI\r
247	XenPvBlkDxeBlockIoFlushBlocks (\r
248	IN EFI_BLOCK_IO_PROTOCOL *This\r
249	)\r
250	{\r
251	XenPvBlockSync (XEN_BLOCK_FRONT_FROM_BLOCK_IO (This));\r
252	return EFI_SUCCESS;\r
253	}\r
254	\r
255	/**\r
256	Reset the block device hardware.\r
257	\r
258	@param[in] This Indicates a pointer to the calling context.\r
259	@param[in] ExtendedVerification Not used.\r
260	\r
261	@retval EFI_SUCCESS The device was reset.\r
262	\r
263	**/\r
264	EFI_STATUS\r
265	EFIAPI\r
266	XenPvBlkDxeBlockIoReset (\r
267	IN EFI_BLOCK_IO_PROTOCOL *This,\r
268	IN BOOLEAN ExtendedVerification\r
269	)\r
270	{\r
271	//\r
272	// Since the initialization of the devices is done, then the device is\r
273	// working correctly.\r
274	//\r
275	return EFI_SUCCESS;\r
276	}\r