[mirror_edk2.git] / MdeModulePkg / Universal / Disk / PartitionDxe / Mbr.c

/** @file\r
  Decode a hard disk partitioned with the legacy MBR found on most PC's\r
\r
  MBR - Master Boot Record is in the first sector of a partitioned hard disk.\r
        The MBR supports four partitions per disk. The MBR also contains legacy\r
        code that is not run on an EFI system. The legacy code reads the \r
        first sector of the active partition into memory and \r
\r
  BPB - BIOS Parameter Block is in the first sector of a FAT file system. \r
        The BPB contains information about the FAT file system. The BPB is \r
        always on the first sector of a media. The first sector also contains\r
        the legacy boot strap code.\r
\r
Copyright (c) 2006 - 2008, Intel Corporation. <BR>\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
**/\r
\r
#include "Partition.h"\r
\r
/**\r
  Test to see if the Mbr buffer is a valid MBR.\r
\r
  @param  Mbr         Parent Handle.\r
  @param  LastLba     Last Lba address on the device.\r
   \r
  @retval TRUE        Mbr is a Valid MBR.\r
  @retval FALSE       Mbr is not a Valid MBR.\r
\r
**/\r
BOOLEAN\r
PartitionValidMbr (\r
  IN  MASTER_BOOT_RECORD      *Mbr,\r
  IN  EFI_LBA                 LastLba\r
  )\r
{\r
  UINT32  StartingLBA;\r
  UINT32  EndingLBA;\r
  UINT32  NewEndingLBA;\r
  INTN    Index1;\r
  INTN    Index2;\r
  BOOLEAN MbrValid;\r
\r
  if (Mbr->Signature != MBR_SIGNATURE) {\r
    return FALSE;\r
  }\r
  //\r
  // The BPB also has this signature, so it can not be used alone.\r
  //\r
  MbrValid = FALSE;\r
  for (Index1 = 0; Index1 < MAX_MBR_PARTITIONS; Index1++) {\r
    if (Mbr->Partition[Index1].OSIndicator == 0x00 || UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) == 0) {\r
      continue;\r
    }\r
\r
    MbrValid    = TRUE;\r
    StartingLBA = UNPACK_UINT32 (Mbr->Partition[Index1].StartingLBA);\r
    EndingLBA   = StartingLBA + UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) - 1;\r
    if (EndingLBA > LastLba) {\r
      //\r
      // Compatibility Errata:\r
      //  Some systems try to hide drive space with their INT 13h driver\r
      //  This does not hide space from the OS driver. This means the MBR\r
      //  that gets created from DOS is smaller than the MBR created from\r
      //  a real OS (NT & Win98). This leads to BlockIo->LastBlock being\r
      //  wrong on some systems FDISKed by the OS.\r
      //\r
      // return FALSE since no block devices on a system are implemented\r
      // with INT 13h\r
      //\r
      return FALSE;\r
    }\r
\r
    for (Index2 = Index1 + 1; Index2 < MAX_MBR_PARTITIONS; Index2++) {\r
      if (Mbr->Partition[Index2].OSIndicator == 0x00 || UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) == 0) {\r
        continue;\r
      }\r
\r
      NewEndingLBA = UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) + UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) - 1;\r
      if (NewEndingLBA >= StartingLBA && UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) <= EndingLBA) {\r
        //\r
        // This region overlaps with the Index1'th region\r
        //\r
        return FALSE;\r
      }\r
    }\r
  }\r
  //\r
  // None of the regions overlapped so MBR is O.K.\r
  //\r
  return MbrValid;\r
}\r
\r
\r
/**\r
  Install child handles if the Handle supports MBR format.\r
\r
  @param  This              Calling context.\r
  @param  Handle            Parent Handle.\r
  @param  DiskIo            Parent DiskIo interface.\r
  @param  BlockIo           Parent BlockIo interface.\r
  @param  DevicePath        Parent Device Path.\r
   \r
  @retval EFI_SUCCESS       A child handle was added.\r
  @retval EFI_MEDIA_CHANGED Media change was detected.\r
  @retval Others            MBR partition was not found.\r
\r
**/\r
EFI_STATUS\r
PartitionInstallMbrChildHandles (\r
  IN  EFI_DRIVER_BINDING_PROTOCOL  *This,\r
  IN  EFI_HANDLE                   Handle,\r
  IN  EFI_DISK_IO_PROTOCOL         *DiskIo,\r
  IN  EFI_BLOCK_IO_PROTOCOL        *BlockIo,\r
  IN  EFI_DEVICE_PATH_PROTOCOL     *DevicePath\r
  )\r
{\r
  EFI_STATUS                Status;\r
  MASTER_BOOT_RECORD        *Mbr;\r
  UINT32                    ExtMbrStartingLba;\r
  UINTN                     Index;\r
  HARDDRIVE_DEVICE_PATH     HdDev;\r
  HARDDRIVE_DEVICE_PATH     ParentHdDev;\r
  EFI_STATUS                Found;\r
  UINT32                    PartitionNumber;\r
  EFI_DEVICE_PATH_PROTOCOL  *DevicePathNode;\r
  EFI_DEVICE_PATH_PROTOCOL  *LastDevicePathNode;\r
\r
  Mbr             = NULL;\r
  Found           = EFI_NOT_FOUND;\r
\r
  Mbr             = AllocatePool (BlockIo->Media->BlockSize);\r
  if (Mbr == NULL) {\r
    goto Done;\r
  }\r
\r
  Status = BlockIo->ReadBlocks (\r
                      BlockIo,\r
                      BlockIo->Media->MediaId,\r
                      0,\r
                      BlockIo->Media->BlockSize,\r
                      Mbr\r
                      );\r
  if (EFI_ERROR (Status)) {\r
    Found = Status;\r
    goto Done;\r
  }\r
  if (!PartitionValidMbr (Mbr, BlockIo->Media->LastBlock)) {\r
    goto Done;\r
  }\r
  //\r
  // We have a valid mbr - add each partition\r
  //\r
  //\r
  // Get starting and ending LBA of the parent block device.\r
  //\r
  LastDevicePathNode = NULL;\r
  ZeroMem (&ParentHdDev, sizeof (ParentHdDev));\r
  DevicePathNode = DevicePath;\r
  while (!IsDevicePathEnd (DevicePathNode)) {\r
    LastDevicePathNode  = DevicePathNode;\r
    DevicePathNode      = NextDevicePathNode (DevicePathNode);\r
  }\r
\r
  if (LastDevicePathNode != NULL) {\r
    if (DevicePathType (LastDevicePathNode) == MEDIA_DEVICE_PATH &&\r
        DevicePathSubType (LastDevicePathNode) == MEDIA_HARDDRIVE_DP\r
        ) {\r
      CopyMem (&ParentHdDev, LastDevicePathNode, sizeof (ParentHdDev));\r
    } else {\r
      LastDevicePathNode = NULL;\r
    }\r
  }\r
\r
  PartitionNumber = 1;\r
\r
  ZeroMem (&HdDev, sizeof (HdDev));\r
  HdDev.Header.Type     = MEDIA_DEVICE_PATH;\r
  HdDev.Header.SubType  = MEDIA_HARDDRIVE_DP;\r
  SetDevicePathNodeLength (&HdDev.Header, sizeof (HdDev));\r
  HdDev.MBRType         = MBR_TYPE_PCAT;\r
  HdDev.SignatureType   = SIGNATURE_TYPE_MBR;\r
\r
  if (LastDevicePathNode == NULL) {\r
    //\r
    // This is a MBR, add each partition\r
    //\r
    for (Index = 0; Index < MAX_MBR_PARTITIONS; Index++) {\r
      if (Mbr->Partition[Index].OSIndicator == 0x00 || UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA) == 0) {\r
        //\r
        // Don't use null MBR entries\r
        //\r
        continue;\r
      }\r
\r
      if (Mbr->Partition[Index].OSIndicator == PMBR_GPT_PARTITION) {\r
        //\r
        // This is the guard MBR for the GPT. If you ever see a GPT disk with zero partitions you can get here.\r
        //  We can not produce an MBR BlockIo for this device as the MBR spans the GPT headers. So formating \r
        //  this BlockIo would corrupt the GPT structures and require a recovery that would corrupt the format\r
        //  that corrupted the GPT partition. \r
        //\r
        continue;\r
      }\r
\r
      HdDev.PartitionNumber = PartitionNumber ++;\r
      HdDev.PartitionStart  = UNPACK_UINT32 (Mbr->Partition[Index].StartingLBA);\r
      HdDev.PartitionSize   = UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA);\r
      CopyMem (HdDev.Signature, &(Mbr->UniqueMbrSignature[0]), sizeof (Mbr->UniqueMbrSignature));\r
\r
      Status = PartitionInstallChildHandle (\r
                This,\r
                Handle,\r
                DiskIo,\r
                BlockIo,\r
                DevicePath,\r
                (EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
                HdDev.PartitionStart,\r
                HdDev.PartitionStart + HdDev.PartitionSize - 1,\r
                MBR_SIZE,\r
                (BOOLEAN) (Mbr->Partition[Index].OSIndicator == EFI_PARTITION)\r
                );\r
\r
      if (!EFI_ERROR (Status)) {\r
        Found = EFI_SUCCESS;\r
      }\r
    }\r
  } else {\r
    //\r
    // It's an extended partition. Follow the extended partition\r
    // chain to get all the logical drives\r
    //\r
    ExtMbrStartingLba = 0;\r
\r
    do {\r
\r
      Status = BlockIo->ReadBlocks (\r
                          BlockIo,\r
                          BlockIo->Media->MediaId,\r
                          ExtMbrStartingLba,\r
                          BlockIo->Media->BlockSize,\r
                          Mbr\r
                          );\r
      if (EFI_ERROR (Status)) {\r
        Found = Status;\r
        goto Done;\r
      }\r
\r
      if (UNPACK_UINT32 (Mbr->Partition[0].SizeInLBA) == 0) {\r
        break;\r
      }\r
\r
      if ((Mbr->Partition[0].OSIndicator == EXTENDED_DOS_PARTITION) ||\r
          (Mbr->Partition[0].OSIndicator == EXTENDED_WINDOWS_PARTITION)) {\r
        ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA);\r
        continue;\r
      }\r
      HdDev.PartitionNumber = PartitionNumber ++;\r
      HdDev.PartitionStart  = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA) + ExtMbrStartingLba + ParentHdDev.PartitionStart;\r
      HdDev.PartitionSize   = UNPACK_UINT32 (Mbr->Partition[0].SizeInLBA);\r
      if ((HdDev.PartitionStart + HdDev.PartitionSize - 1 >= ParentHdDev.PartitionStart + ParentHdDev.PartitionSize) ||\r
          (HdDev.PartitionStart <= ParentHdDev.PartitionStart)) {\r
        break;\r
      }\r
\r
      //\r
      // The signature in EBR(Extended Boot Record) should always be 0.\r
      //\r
      *((UINT32 *) &HdDev.Signature[0]) = 0;\r
\r
      Status = PartitionInstallChildHandle (\r
                This,\r
                Handle,\r
                DiskIo,\r
                BlockIo,\r
                DevicePath,\r
                (EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
                HdDev.PartitionStart - ParentHdDev.PartitionStart,\r
                HdDev.PartitionStart - ParentHdDev.PartitionStart + HdDev.PartitionSize - 1,\r
                MBR_SIZE,\r
                (BOOLEAN) (Mbr->Partition[0].OSIndicator == EFI_PARTITION)\r
                );\r
      if (!EFI_ERROR (Status)) {\r
        Found = EFI_SUCCESS;\r
      }\r
\r
      if ((Mbr->Partition[1].OSIndicator != EXTENDED_DOS_PARTITION) &&\r
          (Mbr->Partition[1].OSIndicator != EXTENDED_WINDOWS_PARTITION)\r
          ) {\r
        break;\r
      }\r
\r
      ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[1].StartingLBA);\r
      //\r
      // Don't allow partition to be self referencing\r
      //\r
      if (ExtMbrStartingLba == 0) {\r
        break;\r
      }\r
    } while (ExtMbrStartingLba  < ParentHdDev.PartitionSize);\r
  }\r
\r
Done:\r
  FreePool (Mbr);\r
\r
  return Found;\r
}\r
Commit	Line	Data
f42be642	1	/** @file\r
adbcbf8f	2	Decode a hard disk partitioned with the legacy MBR found on most PC's\r
	3	\r
	4	MBR - Master Boot Record is in the first sector of a partitioned hard disk.\r
	5	The MBR supports four partitions per disk. The MBR also contains legacy\r
	6	code that is not run on an EFI system. The legacy code reads the \r
	7	first sector of the active partition into memory and \r
	8	\r
48557c65	9	BPB - BIOS Parameter Block is in the first sector of a FAT file system. \r
adbcbf8f	10	The BPB contains information about the FAT file system. The BPB is \r
	11	always on the first sector of a media. The first sector also contains\r
	12	the legacy boot strap code.\r
	13	\r
f42be642	14	Copyright (c) 2006 - 2008, Intel Corporation. <BR>\r
	15	All rights reserved. This program and the accompanying materials\r
	16	are licensed and made available under the terms and conditions of the BSD License\r
	17	which accompanies this distribution. The full text of the license may be found at\r
	18	http://opensource.org/licenses/bsd-license.php\r
	19	\r
	20	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	21	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	22	\r
	23	**/\r
adbcbf8f	24	\r
	25	#include "Partition.h"\r
	26	\r
a8d0c20e	27	/**\r
	28	Test to see if the Mbr buffer is a valid MBR.\r
	29	\r
	30	@param Mbr Parent Handle.\r
	31	@param LastLba Last Lba address on the device.\r
	32	\r
	33	@retval TRUE Mbr is a Valid MBR.\r
	34	@retval FALSE Mbr is not a Valid MBR.\r
	35	\r
	36	**/\r
adbcbf8f	37	BOOLEAN\r
	38	PartitionValidMbr (\r
	39	IN MASTER_BOOT_RECORD *Mbr,\r
	40	IN EFI_LBA LastLba\r
	41	)\r
adbcbf8f	42	{\r
	43	UINT32 StartingLBA;\r
	44	UINT32 EndingLBA;\r
	45	UINT32 NewEndingLBA;\r
	46	INTN Index1;\r
	47	INTN Index2;\r
	48	BOOLEAN MbrValid;\r
	49	\r
	50	if (Mbr->Signature != MBR_SIGNATURE) {\r
	51	return FALSE;\r
	52	}\r
	53	//\r
	54	// The BPB also has this signature, so it can not be used alone.\r
	55	//\r
	56	MbrValid = FALSE;\r
	57	for (Index1 = 0; Index1 < MAX_MBR_PARTITIONS; Index1++) {\r
	58	if (Mbr->Partition[Index1].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) == 0) {\r
	59	continue;\r
	60	}\r
	61	\r
	62	MbrValid = TRUE;\r
	63	StartingLBA = UNPACK_UINT32 (Mbr->Partition[Index1].StartingLBA);\r
	64	EndingLBA = StartingLBA + UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) - 1;\r
	65	if (EndingLBA > LastLba) {\r
	66	//\r
	67	// Compatibility Errata:\r
	68	// Some systems try to hide drive space with their INT 13h driver\r
	69	// This does not hide space from the OS driver. This means the MBR\r
	70	// that gets created from DOS is smaller than the MBR created from\r
	71	// a real OS (NT & Win98). This leads to BlockIo->LastBlock being\r
	72	// wrong on some systems FDISKed by the OS.\r
	73	//\r
	74	// return FALSE since no block devices on a system are implemented\r
	75	// with INT 13h\r
	76	//\r
	77	return FALSE;\r
	78	}\r
	79	\r
	80	for (Index2 = Index1 + 1; Index2 < MAX_MBR_PARTITIONS; Index2++) {\r
	81	if (Mbr->Partition[Index2].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) == 0) {\r
	82	continue;\r
	83	}\r
	84	\r
	85	NewEndingLBA = UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) + UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) - 1;\r
	86	if (NewEndingLBA >= StartingLBA && UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) <= EndingLBA) {\r
	87	//\r
	88	// This region overlaps with the Index1'th region\r
	89	//\r
	90	return FALSE;\r
	91	}\r
	92	}\r
	93	}\r
	94	//\r
ea7cb08c	95	// None of the regions overlapped so MBR is O.K.\r
adbcbf8f	96	//\r
	97	return MbrValid;\r
	98	}\r
	99	\r
a8d0c20e	100	\r
	101	/**\r
	102	Install child handles if the Handle supports MBR format.\r
	103	\r
	104	@param This Calling context.\r
	105	@param Handle Parent Handle.\r
	106	@param DiskIo Parent DiskIo interface.\r
	107	@param BlockIo Parent BlockIo interface.\r
	108	@param DevicePath Parent Device Path.\r
	109	\r
	110	@retval EFI_SUCCESS A child handle was added.\r
	111	@retval EFI_MEDIA_CHANGED Media change was detected.\r
	112	@retval Others MBR partition was not found.\r
	113	\r
	114	**/\r
adbcbf8f	115	EFI_STATUS\r
	116	PartitionInstallMbrChildHandles (\r
	117	IN EFI_DRIVER_BINDING_PROTOCOL *This,\r
	118	IN EFI_HANDLE Handle,\r
	119	IN EFI_DISK_IO_PROTOCOL *DiskIo,\r
	120	IN EFI_BLOCK_IO_PROTOCOL *BlockIo,\r
	121	IN EFI_DEVICE_PATH_PROTOCOL *DevicePath\r
	122	)\r
adbcbf8f	123	{\r
	124	EFI_STATUS Status;\r
	125	MASTER_BOOT_RECORD *Mbr;\r
	126	UINT32 ExtMbrStartingLba;\r
	127	UINTN Index;\r
	128	HARDDRIVE_DEVICE_PATH HdDev;\r
	129	HARDDRIVE_DEVICE_PATH ParentHdDev;\r
	130	EFI_STATUS Found;\r
	131	UINT32 PartitionNumber;\r
	132	EFI_DEVICE_PATH_PROTOCOL *DevicePathNode;\r
	133	EFI_DEVICE_PATH_PROTOCOL *LastDevicePathNode;\r
	134	\r
	135	Mbr = NULL;\r
	136	Found = EFI_NOT_FOUND;\r
	137	\r
	138	Mbr = AllocatePool (BlockIo->Media->BlockSize);\r
	139	if (Mbr == NULL) {\r
	140	goto Done;\r
	141	}\r
	142	\r
	143	Status = BlockIo->ReadBlocks (\r
	144	BlockIo,\r
	145	BlockIo->Media->MediaId,\r
	146	0,\r
	147	BlockIo->Media->BlockSize,\r
	148	Mbr\r
	149	);\r
	150	if (EFI_ERROR (Status)) {\r
	151	Found = Status;\r
	152	goto Done;\r
	153	}\r
	154	if (!PartitionValidMbr (Mbr, BlockIo->Media->LastBlock)) {\r
	155	goto Done;\r
	156	}\r
	157	//\r
	158	// We have a valid mbr - add each partition\r
	159	//\r
	160	//\r
	161	// Get starting and ending LBA of the parent block device.\r
	162	//\r
	163	LastDevicePathNode = NULL;\r
	164	ZeroMem (&ParentHdDev, sizeof (ParentHdDev));\r
	165	DevicePathNode = DevicePath;\r
1232b214	166	while (!IsDevicePathEnd (DevicePathNode)) {\r
adbcbf8f	167	LastDevicePathNode = DevicePathNode;\r
1232b214	168	DevicePathNode = NextDevicePathNode (DevicePathNode);\r
adbcbf8f	169	}\r
	170	\r
	171	if (LastDevicePathNode != NULL) {\r
	172	if (DevicePathType (LastDevicePathNode) == MEDIA_DEVICE_PATH &&\r
	173	DevicePathSubType (LastDevicePathNode) == MEDIA_HARDDRIVE_DP\r
	174	) {\r
	175	CopyMem (&ParentHdDev, LastDevicePathNode, sizeof (ParentHdDev));\r
	176	} else {\r
	177	LastDevicePathNode = NULL;\r
	178	}\r
	179	}\r
	180	\r
	181	PartitionNumber = 1;\r
	182	\r
	183	ZeroMem (&HdDev, sizeof (HdDev));\r
	184	HdDev.Header.Type = MEDIA_DEVICE_PATH;\r
	185	HdDev.Header.SubType = MEDIA_HARDDRIVE_DP;\r
	186	SetDevicePathNodeLength (&HdDev.Header, sizeof (HdDev));\r
	187	HdDev.MBRType = MBR_TYPE_PCAT;\r
	188	HdDev.SignatureType = SIGNATURE_TYPE_MBR;\r
	189	\r
	190	if (LastDevicePathNode == NULL) {\r
	191	//\r
	192	// This is a MBR, add each partition\r
	193	//\r
	194	for (Index = 0; Index < MAX_MBR_PARTITIONS; Index++) {\r
	195	if (Mbr->Partition[Index].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA) == 0) {\r
	196	//\r
	197	// Don't use null MBR entries\r
	198	//\r
	199	continue;\r
	200	}\r
	201	\r
	202	if (Mbr->Partition[Index].OSIndicator == PMBR_GPT_PARTITION) {\r
	203	//\r
	204	// This is the guard MBR for the GPT. If you ever see a GPT disk with zero partitions you can get here.\r
	205	// We can not produce an MBR BlockIo for this device as the MBR spans the GPT headers. So formating \r
	206	// this BlockIo would corrupt the GPT structures and require a recovery that would corrupt the format\r
	207	// that corrupted the GPT partition. \r
	208	//\r
	209	continue;\r
	210	}\r
	211	\r
	212	HdDev.PartitionNumber = PartitionNumber ++;\r
	213	HdDev.PartitionStart = UNPACK_UINT32 (Mbr->Partition[Index].StartingLBA);\r
	214	HdDev.PartitionSize = UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA);\r
48557c65	215	CopyMem (HdDev.Signature, &(Mbr->UniqueMbrSignature[0]), sizeof (Mbr->UniqueMbrSignature));\r
adbcbf8f	216	\r
	217	Status = PartitionInstallChildHandle (\r
	218	This,\r
	219	Handle,\r
	220	DiskIo,\r
	221	BlockIo,\r
	222	DevicePath,\r
	223	(EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
	224	HdDev.PartitionStart,\r
	225	HdDev.PartitionStart + HdDev.PartitionSize - 1,\r
	226	MBR_SIZE,\r
	227	(BOOLEAN) (Mbr->Partition[Index].OSIndicator == EFI_PARTITION)\r
	228	);\r
	229	\r
	230	if (!EFI_ERROR (Status)) {\r
	231	Found = EFI_SUCCESS;\r
	232	}\r
	233	}\r
	234	} else {\r
	235	//\r
	236	// It's an extended partition. Follow the extended partition\r
	237	// chain to get all the logical drives\r
	238	//\r
	239	ExtMbrStartingLba = 0;\r
	240	\r
	241	do {\r
	242	\r
	243	Status = BlockIo->ReadBlocks (\r
	244	BlockIo,\r
	245	BlockIo->Media->MediaId,\r
	246	ExtMbrStartingLba,\r
	247	BlockIo->Media->BlockSize,\r
	248	Mbr\r
	249	);\r
	250	if (EFI_ERROR (Status)) {\r
	251	Found = Status;\r
	252	goto Done;\r
	253	}\r
	254	\r
c63cd426	255	if (UNPACK_UINT32 (Mbr->Partition[0].SizeInLBA) == 0) {\r
adbcbf8f	256	break;\r
	257	}\r
	258	\r
	259	if ((Mbr->Partition[0].OSIndicator == EXTENDED_DOS_PARTITION) \|\|\r
	260	(Mbr->Partition[0].OSIndicator == EXTENDED_WINDOWS_PARTITION)) {\r
	261	ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA);\r
	262	continue;\r
	263	}\r
	264	HdDev.PartitionNumber = PartitionNumber ++;\r
	265	HdDev.PartitionStart = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA) + ExtMbrStartingLba + ParentHdDev.PartitionStart;\r
	266	HdDev.PartitionSize = UNPACK_UINT32 (Mbr->Partition[0].SizeInLBA);\r
	267	if ((HdDev.PartitionStart + HdDev.PartitionSize - 1 >= ParentHdDev.PartitionStart + ParentHdDev.PartitionSize) \|\|\r
	268	(HdDev.PartitionStart <= ParentHdDev.PartitionStart)) {\r
	269	break;\r
	270	}\r
	271	\r
	272	//\r
	273	// The signature in EBR(Extended Boot Record) should always be 0.\r
	274	//\r
	275	((UINT32 ) &HdDev.Signature[0]) = 0;\r
	276	\r
	277	Status = PartitionInstallChildHandle (\r
	278	This,\r
	279	Handle,\r
	280	DiskIo,\r
	281	BlockIo,\r
	282	DevicePath,\r
	283	(EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
	284	HdDev.PartitionStart - ParentHdDev.PartitionStart,\r
	285	HdDev.PartitionStart - ParentHdDev.PartitionStart + HdDev.PartitionSize - 1,\r
	286	MBR_SIZE,\r
	287	(BOOLEAN) (Mbr->Partition[0].OSIndicator == EFI_PARTITION)\r
	288	);\r
	289	if (!EFI_ERROR (Status)) {\r
	290	Found = EFI_SUCCESS;\r
	291	}\r
	292	\r
	293	if ((Mbr->Partition[1].OSIndicator != EXTENDED_DOS_PARTITION) &&\r
	294	(Mbr->Partition[1].OSIndicator != EXTENDED_WINDOWS_PARTITION)\r
	295	) {\r
	296	break;\r
	297	}\r
	298	\r
	299	ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[1].StartingLBA);\r
	300	//\r
	301	// Don't allow partition to be self referencing\r
	302	//\r
	303	if (ExtMbrStartingLba == 0) {\r
	304	break;\r
	305	}\r
	306	} while (ExtMbrStartingLba < ParentHdDev.PartitionSize);\r
	307	}\r
	308	\r
	309	Done:\r
	310	FreePool (Mbr);\r
	311	\r
	312	return Found;\r
	313	}\r