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      1 /** @file
      2   EFI Guid Partition Table Format Definition.
      3 
      4 Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
      5 This program and the accompanying materials are licensed and made available under
      6 the terms and conditions of the BSD License that accompanies this distribution.
      7 The full text of the license may be found at
      8 http://opensource.org/licenses/bsd-license.php.
      9 
     10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
     11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
     12 
     13 **/
     14 
     15 #ifndef __UEFI_GPT_H__
     16 #define __UEFI_GPT_H__
     17 
     18 ///
     19 /// The primary GUID Partition Table Header must be
     20 /// located in LBA 1 (i.e., the second logical block).
     21 ///
     22 #define PRIMARY_PART_HEADER_LBA 1
     23 ///
     24 /// EFI Partition Table Signature: "EFI PART".
     25 ///
     26 #define EFI_PTAB_HEADER_ID      SIGNATURE_64 ('E','F','I',' ','P','A','R','T')
     27 
     28 #pragma pack(1)
     29 
     30 ///
     31 /// GPT Partition Table Header.
     32 ///
     33 typedef struct {
     34   ///
     35   /// The table header for the GPT partition Table.
     36   /// This header contains EFI_PTAB_HEADER_ID.
     37   ///
     38   EFI_TABLE_HEADER  Header;
     39   ///
     40   /// The LBA that contains this data structure.
     41   ///
     42   EFI_LBA           MyLBA;
     43   ///
     44   /// LBA address of the alternate GUID Partition Table Header.
     45   ///
     46   EFI_LBA           AlternateLBA;
     47   ///
     48   /// The first usable logical block that may be used
     49   /// by a partition described by a GUID Partition Entry.
     50   ///
     51   EFI_LBA           FirstUsableLBA;
     52   ///
     53   /// The last usable logical block that may be used
     54   /// by a partition described by a GUID Partition Entry.
     55   ///
     56   EFI_LBA           LastUsableLBA;
     57   ///
     58   /// GUID that can be used to uniquely identify the disk.
     59   ///
     60   EFI_GUID          DiskGUID;
     61   ///
     62   /// The starting LBA of the GUID Partition Entry array.
     63   ///
     64   EFI_LBA           PartitionEntryLBA;
     65   ///
     66   /// The number of Partition Entries in the GUID Partition Entry array.
     67   ///
     68   UINT32            NumberOfPartitionEntries;
     69   ///
     70   /// The size, in bytes, of each the GUID Partition
     71   /// Entry structures in the GUID Partition Entry
     72   /// array. This field shall be set to a value of 128 x 2^n where n is
     73   /// an integer greater than or equal to zero (e.g., 128, 256, 512, etc.).
     74   ///
     75   UINT32            SizeOfPartitionEntry;
     76   ///
     77   /// The CRC32 of the GUID Partition Entry array.
     78   /// Starts at PartitionEntryLBA and is
     79   /// computed over a byte length of
     80   /// NumberOfPartitionEntries * SizeOfPartitionEntry.
     81   ///
     82   UINT32            PartitionEntryArrayCRC32;
     83 } EFI_PARTITION_TABLE_HEADER;
     84 
     85 ///
     86 /// GPT Partition Entry.
     87 ///
     88 typedef struct {
     89   ///
     90   /// Unique ID that defines the purpose and type of this Partition. A value of
     91   /// zero defines that this partition entry is not being used.
     92   ///
     93   EFI_GUID  PartitionTypeGUID;
     94   ///
     95   /// GUID that is unique for every partition entry. Every partition ever
     96   /// created will have a unique GUID.
     97   /// This GUID must be assigned when the GUID Partition Entry is created.
     98   ///
     99   EFI_GUID  UniquePartitionGUID;
    100   ///
    101   /// Starting LBA of the partition defined by this entry
    102   ///
    103   EFI_LBA   StartingLBA;
    104   ///
    105   /// Ending LBA of the partition defined by this entry.
    106   ///
    107   EFI_LBA   EndingLBA;
    108   ///
    109   /// Attribute bits, all bits reserved by UEFI
    110   /// Bit 0:      If this bit is set, the partition is required for the platform to function. The owner/creator of the
    111   ///             partition indicates that deletion or modification of the contents can result in loss of platform
    112   ///             features or failure for the platform to boot or operate. The system cannot function normally if
    113   ///             this partition is removed, and it should be considered part of the hardware of the system.
    114   ///             Actions such as running diagnostics, system recovery, or even OS install or boot, could
    115   ///             potentially stop working if this partition is removed. Unless OS software or firmware
    116   ///             recognizes this partition, it should never be removed or modified as the UEFI firmware or
    117   ///             platform hardware may become non-functional.
    118   /// Bit 1:      If this bit is set, then firmware must not produce an EFI_BLOCK_IO_PROTOCOL device for
    119   ///             this partition. By not producing an EFI_BLOCK_IO_PROTOCOL partition, file system
    120   ///             mappings will not be created for this partition in UEFI.
    121   /// Bit 2:      This bit is set aside to let systems with traditional PC-AT BIOS firmware implementations
    122   ///             inform certain limited, special-purpose software running on these systems that a GPT
    123   ///             partition may be bootable. The UEFI boot manager must ignore this bit when selecting
    124   ///             a UEFI-compliant application, e.g., an OS loader.
    125   /// Bits 3-47:  Undefined and must be zero. Reserved for expansion by future versions of the UEFI
    126   ///             specification.
    127   /// Bits 48-63: Reserved for GUID specific use. The use of these bits will vary depending on the
    128   ///             PartitionTypeGUID. Only the owner of the PartitionTypeGUID is allowed
    129   ///             to modify these bits. They must be preserved if Bits 0-47 are modified..
    130   ///
    131   UINT64    Attributes;
    132   ///
    133   /// Null-terminated name of the partition.
    134   ///
    135   CHAR16    PartitionName[36];
    136 } EFI_PARTITION_ENTRY;
    137 
    138 #pragma pack()
    139 #endif
    140 
    141 
    142