[mirror_edk2.git] / EdkModulePkg / Universal / Disk / Partition / Dxe / Mbr.c

/*++\r
\r
Copyright (c) 2006, 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
  Mbr.c\r
  \r
Abstract:\r
\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 - Boot(?) 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
--*/\r
\r
#include "Partition.h"\r
\r
BOOLEAN\r
PartitionValidMbr (\r
  IN  MASTER_BOOT_RECORD      *Mbr,\r
  IN  EFI_LBA                 LastLba\r
  )\r
/*++\r
\r
Routine Description:\r
  Test to see if the Mbr buffer is a valid MBR\r
\r
Arguments:       \r
  Mbr     - Parent Handle \r
  LastLba - Last Lba address on the device.\r
\r
Returns:\r
  TRUE  - Mbr is a Valid MBR\r
  FALSE - Mbr is not a Valid MBR\r
\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
  // Non of the regions overlapped so MBR is O.K.\r
  //\r
  return MbrValid;\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
\r
Routine Description:\r
  Install child handles if the Handle supports MBR format.\r
\r
Arguments:       \r
  This       - Calling context.\r
  Handle     - Parent Handle \r
  DiskIo     - Parent DiskIo interface\r
  BlockIo    - Parent BlockIo interface\r
  DevicePath - Parent Device Path\r
\r
Returns:\r
  EFI_SUCCESS       - If a child handle was added\r
  EFI_MEDIA_CHANGED - Media changed Detected\r
	!EFI_SUCCESS      - Not found MBR partition.\r
\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) || !PartitionValidMbr (Mbr, BlockIo->Media->LastBlock)) {\r
    Found = Status;\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 (!EfiIsDevicePathEnd (DevicePathNode)) {\r
    LastDevicePathNode  = DevicePathNode;\r
    DevicePathNode      = EfiNextDevicePathNode (DevicePathNode);\r
  }\r
\r
  if (LastDevicePathNode != NULL) {\r
    if (DevicePathType (LastDevicePathNode) == MEDIA_DEVICE_PATH &&\r
        DevicePathSubType (LastDevicePathNode) == MEDIA_HARDDRIVE_DP\r
        ) {\r
      gBS->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 (UINT32));\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 (Mbr->Partition[0].OSIndicator == 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 >=\r
            ParentHdDev.PartitionStart + ParentHdDev.PartitionSize) {\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
  gBS->FreePool (Mbr);\r
\r
  return Found;\r
}\r
Commit	Line	Data
878ddf1f	1	/*++\r
	2	\r
	3	Copyright (c) 2006, Intel Corporation \r
	4	All rights reserved. This program and the accompanying materials \r
	5	are licensed and made available under the terms and conditions of the BSD License \r
	6	which accompanies this distribution. The full text of the license may be found at \r
	7	http://opensource.org/licenses/bsd-license.php \r
	8	\r
	9	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
	10	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
	11	\r
	12	Module Name:\r
	13	\r
	14	Mbr.c\r
	15	\r
	16	Abstract:\r
	17	\r
	18	Decode a hard disk partitioned with the legacy MBR found on most PC's\r
	19	\r
	20	MBR - Master Boot Record is in the first sector of a partitioned hard disk.\r
	21	The MBR supports four partitions per disk. The MBR also contains legacy\r
	22	code that is not run on an EFI system. The legacy code reads the \r
	23	first sector of the active partition into memory and \r
	24	\r
	25	BPB - Boot(?) Parameter Block is in the first sector of a FAT file system. \r
	26	The BPB contains information about the FAT file system. The BPB is \r
	27	always on the first sector of a media. The first sector also contains\r
	28	the legacy boot strap code.\r
	29	\r
	30	--*/\r
	31	\r
	32	#include "Partition.h"\r
878ddf1f	33	\r
	34	BOOLEAN\r
	35	PartitionValidMbr (\r
	36	IN MASTER_BOOT_RECORD *Mbr,\r
	37	IN EFI_LBA LastLba\r
	38	)\r
	39	/*++\r
	40	\r
	41	Routine Description:\r
	42	Test to see if the Mbr buffer is a valid MBR\r
	43	\r
	44	Arguments: \r
	45	Mbr - Parent Handle \r
	46	LastLba - Last Lba address on the device.\r
	47	\r
	48	Returns:\r
	49	TRUE - Mbr is a Valid MBR\r
	50	FALSE - Mbr is not a Valid MBR\r
	51	\r
	52	--*/\r
	53	{\r
	54	UINT32 StartingLBA;\r
	55	UINT32 EndingLBA;\r
	56	UINT32 NewEndingLBA;\r
	57	INTN Index1;\r
	58	INTN Index2;\r
	59	BOOLEAN MbrValid;\r
	60	\r
	61	if (Mbr->Signature != MBR_SIGNATURE) {\r
	62	return FALSE;\r
	63	}\r
	64	//\r
	65	// The BPB also has this signature, so it can not be used alone.\r
	66	//\r
	67	MbrValid = FALSE;\r
	68	for (Index1 = 0; Index1 < MAX_MBR_PARTITIONS; Index1++) {\r
	69	if (Mbr->Partition[Index1].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) == 0) {\r
	70	continue;\r
	71	}\r
	72	\r
	73	MbrValid = TRUE;\r
	74	StartingLBA = UNPACK_UINT32 (Mbr->Partition[Index1].StartingLBA);\r
	75	EndingLBA = StartingLBA + UNPACK_UINT32 (Mbr->Partition[Index1].SizeInLBA) - 1;\r
	76	if (EndingLBA > LastLba) {\r
	77	//\r
	78	// Compatibility Errata:\r
	79	// Some systems try to hide drive space with their INT 13h driver\r
	80	// This does not hide space from the OS driver. This means the MBR\r
	81	// that gets created from DOS is smaller than the MBR created from\r
	82	// a real OS (NT & Win98). This leads to BlockIo->LastBlock being\r
	83	// wrong on some systems FDISKed by the OS.\r
	84	//\r
	85	// return FALSE since no block devices on a system are implemented\r
	86	// with INT 13h\r
	87	//\r
	88	return FALSE;\r
	89	}\r
	90	\r
	91	for (Index2 = Index1 + 1; Index2 < MAX_MBR_PARTITIONS; Index2++) {\r
	92	if (Mbr->Partition[Index2].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) == 0) {\r
	93	continue;\r
	94	}\r
	95	\r
	96	NewEndingLBA = UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) + UNPACK_UINT32 (Mbr->Partition[Index2].SizeInLBA) - 1;\r
97	if (NewEndingLBA >= StartingLBA && UNPACK_UINT32 (Mbr->Partition[Index2].StartingLBA) <= EndingLBA) {\r
98	//\r
99	// This region overlaps with the Index1'th region\r
100	//\r
101	return FALSE;\r
102	}\r
103	}\r
104	}\r
105	//\r
106	// Non of the regions overlapped so MBR is O.K.\r
107	//\r
108	return MbrValid;\r
109	}\r
110	\r
c7c02fab	111	EFI_STATUS\r
878ddf1f	112	PartitionInstallMbrChildHandles (\r
	113	IN EFI_DRIVER_BINDING_PROTOCOL *This,\r
	114	IN EFI_HANDLE Handle,\r
	115	IN EFI_DISK_IO_PROTOCOL *DiskIo,\r
	116	IN EFI_BLOCK_IO_PROTOCOL *BlockIo,\r
	117	IN EFI_DEVICE_PATH_PROTOCOL *DevicePath\r
	118	)\r
	119	/*++\r
	120	\r
	121	Routine Description:\r
	122	Install child handles if the Handle supports MBR format.\r
	123	\r
	124	Arguments: \r
	125	This - Calling context.\r
	126	Handle - Parent Handle \r
	127	DiskIo - Parent DiskIo interface\r
	128	BlockIo - Parent BlockIo interface\r
	129	DevicePath - Parent Device Path\r
	130	\r
	131	Returns:\r
c7c02fab	132	EFI_SUCCESS - If a child handle was added\r
	133	EFI_MEDIA_CHANGED - Media changed Detected\r
	134	!EFI_SUCCESS - Not found MBR partition.\r
878ddf1f	135	\r
	136	--*/\r
	137	{\r
	138	EFI_STATUS Status;\r
	139	MASTER_BOOT_RECORD *Mbr;\r
	140	UINT32 ExtMbrStartingLba;\r
	141	UINTN Index;\r
	142	HARDDRIVE_DEVICE_PATH HdDev;\r
	143	HARDDRIVE_DEVICE_PATH ParentHdDev;\r
c7c02fab	144	EFI_STATUS Found;\r
878ddf1f	145	UINT32 PartitionNumber;\r
	146	EFI_DEVICE_PATH_PROTOCOL *DevicePathNode;\r
	147	EFI_DEVICE_PATH_PROTOCOL *LastDevicePathNode;\r
	148	\r
	149	Mbr = NULL;\r
c7c02fab	150	Found = EFI_NOT_FOUND;\r
878ddf1f	151	\r
	152	Mbr = AllocatePool (BlockIo->Media->BlockSize);\r
	153	if (Mbr == NULL) {\r
	154	goto Done;\r
	155	}\r
	156	\r
	157	Status = BlockIo->ReadBlocks (\r
	158	BlockIo,\r
	159	BlockIo->Media->MediaId,\r
	160	0,\r
	161	BlockIo->Media->BlockSize,\r
	162	Mbr\r
	163	);\r
	164	if (EFI_ERROR (Status) \|\| !PartitionValidMbr (Mbr, BlockIo->Media->LastBlock)) {\r
c7c02fab	165	Found = Status;\r
878ddf1f	166	goto Done;\r
	167	}\r
	168	//\r
	169	// We have a valid mbr - add each partition\r
	170	//\r
	171	//\r
	172	// Get starting and ending LBA of the parent block device.\r
	173	//\r
	174	LastDevicePathNode = NULL;\r
	175	ZeroMem (&ParentHdDev, sizeof (ParentHdDev));\r
	176	DevicePathNode = DevicePath;\r
	177	while (!EfiIsDevicePathEnd (DevicePathNode)) {\r
	178	LastDevicePathNode = DevicePathNode;\r
	179	DevicePathNode = EfiNextDevicePathNode (DevicePathNode);\r
	180	}\r
	181	\r
	182	if (LastDevicePathNode != NULL) {\r
	183	if (DevicePathType (LastDevicePathNode) == MEDIA_DEVICE_PATH &&\r
	184	DevicePathSubType (LastDevicePathNode) == MEDIA_HARDDRIVE_DP\r
	185	) {\r
	186	gBS->CopyMem (&ParentHdDev, LastDevicePathNode, sizeof (ParentHdDev));\r
	187	} else {\r
	188	LastDevicePathNode = NULL;\r
	189	}\r
	190	}\r
	191	\r
	192	PartitionNumber = 1;\r
	193	\r
	194	ZeroMem (&HdDev, sizeof (HdDev));\r
	195	HdDev.Header.Type = MEDIA_DEVICE_PATH;\r
	196	HdDev.Header.SubType = MEDIA_HARDDRIVE_DP;\r
	197	SetDevicePathNodeLength (&HdDev.Header, sizeof (HdDev));\r
	198	HdDev.MBRType = MBR_TYPE_PCAT;\r
	199	HdDev.SignatureType = SIGNATURE_TYPE_MBR;\r
	200	\r
	201	if (LastDevicePathNode == NULL) {\r
	202	//\r
	203	// This is a MBR, add each partition\r
	204	//\r
	205	for (Index = 0; Index < MAX_MBR_PARTITIONS; Index++) {\r
	206	if (Mbr->Partition[Index].OSIndicator == 0x00 \|\| UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA) == 0) {\r
	207	//\r
	208	// Don't use null MBR entries\r
	209	//\r
	210	continue;\r
	211	}\r
	212	\r
3114b334	213	if (Mbr->Partition[Index].OSIndicator == PMBR_GPT_PARTITION) {\r
878ddf1f	214	//\r
	215	// This is the guard MBR for the GPT. If you ever see a GPT disk with zero partitions you can get here.\r
	216	// We can not produce an MBR BlockIo for this device as the MBR spans the GPT headers. So formating \r
	217	// this BlockIo would corrupt the GPT structures and require a recovery that would corrupt the format\r
	218	// that corrupted the GPT partition. \r
	219	//\r
	220	continue;\r
	221	}\r
	222	\r
	223	HdDev.PartitionNumber = PartitionNumber ++;\r
	224	HdDev.PartitionStart = UNPACK_UINT32 (Mbr->Partition[Index].StartingLBA);\r
	225	HdDev.PartitionSize = UNPACK_UINT32 (Mbr->Partition[Index].SizeInLBA);\r
	226	CopyMem (HdDev.Signature, &(Mbr->UniqueMbrSignature[0]), sizeof (UINT32));\r
	227	\r
	228	Status = PartitionInstallChildHandle (\r
	229	This,\r
	230	Handle,\r
	231	DiskIo,\r
	232	BlockIo,\r
	233	DevicePath,\r
	234	(EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
	235	HdDev.PartitionStart,\r
	236	HdDev.PartitionStart + HdDev.PartitionSize - 1,\r
	237	MBR_SIZE,\r
	238	(BOOLEAN) (Mbr->Partition[Index].OSIndicator == EFI_PARTITION)\r
	239	);\r
	240	\r
	241	if (!EFI_ERROR (Status)) {\r
c7c02fab	242	Found = EFI_SUCCESS;\r
878ddf1f	243	}\r
	244	}\r
	245	} else {\r
	246	//\r
	247	// It's an extended partition. Follow the extended partition\r
	248	// chain to get all the logical drives\r
	249	//\r
	250	ExtMbrStartingLba = 0;\r
	251	\r
	252	do {\r
	253	\r
	254	Status = BlockIo->ReadBlocks (\r
	255	BlockIo,\r
	256	BlockIo->Media->MediaId,\r
	257	ExtMbrStartingLba,\r
	258	BlockIo->Media->BlockSize,\r
	259	Mbr\r
	260	);\r
	261	if (EFI_ERROR (Status)) {\r
c7c02fab	262	Found = Status;\r
878ddf1f	263	goto Done;\r
	264	}\r
	265	\r
	266	if (Mbr->Partition[0].OSIndicator == 0) {\r
	267	break;\r
	268	}\r
	269	\r
3114b334	270	if ((Mbr->Partition[0].OSIndicator == EXTENDED_DOS_PARTITION) \|\|\r
	271	(Mbr->Partition[0].OSIndicator == EXTENDED_WINDOWS_PARTITION)) {\r
	272	ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA);\r
	273	continue;\r
	274	}\r
878ddf1f	275	HdDev.PartitionNumber = PartitionNumber ++;\r
	276	HdDev.PartitionStart = UNPACK_UINT32 (Mbr->Partition[0].StartingLBA) + ExtMbrStartingLba + ParentHdDev.PartitionStart;\r
	277	HdDev.PartitionSize = UNPACK_UINT32 (Mbr->Partition[0].SizeInLBA);\r
	278	if (HdDev.PartitionStart + HdDev.PartitionSize - 1 >=\r
	279	ParentHdDev.PartitionStart + ParentHdDev.PartitionSize) {\r
	280	break;\r
	281	}\r
	282	\r
	283	//\r
	284	// The signature in EBR(Extended Boot Record) should always be 0.\r
	285	//\r
	286	((UINT32 ) &HdDev.Signature[0]) = 0;\r
	287	\r
	288	Status = PartitionInstallChildHandle (\r
	289	This,\r
	290	Handle,\r
	291	DiskIo,\r
	292	BlockIo,\r
	293	DevicePath,\r
	294	(EFI_DEVICE_PATH_PROTOCOL *) &HdDev,\r
	295	HdDev.PartitionStart - ParentHdDev.PartitionStart,\r
	296	HdDev.PartitionStart - ParentHdDev.PartitionStart + HdDev.PartitionSize - 1,\r
	297	MBR_SIZE,\r
	298	(BOOLEAN) (Mbr->Partition[0].OSIndicator == EFI_PARTITION)\r
	299	);\r
	300	if (!EFI_ERROR (Status)) {\r
c7c02fab	301	Found = EFI_SUCCESS;\r
878ddf1f	302	}\r
878ddf1f	303	\r
3114b334	304	if ((Mbr->Partition[1].OSIndicator != EXTENDED_DOS_PARTITION) &&\r
3114b334	305	(Mbr->Partition[1].OSIndicator != EXTENDED_WINDOWS_PARTITION)\r
878ddf1f	306	) {\r
	307	break;\r
	308	}\r
	309	\r
	310	ExtMbrStartingLba = UNPACK_UINT32 (Mbr->Partition[1].StartingLBA);\r
	311	//\r
	312	// Don't allow partition to be self referencing\r
	313	//\r
	314	if (ExtMbrStartingLba == 0) {\r
	315	break;\r
	316	}\r
	317	} while (ExtMbrStartingLba < ParentHdDev.PartitionSize);\r
	318	}\r
	319	\r
	320	Done:\r
	321	gBS->FreePool (Mbr);\r
	322	\r
	323	return Found;\r
	324	}\r