xref: /freebsd/sys/contrib/edk2/Include/Uefi/UefiGpt.h (revision 3416500aef140042c64bc149cb1ec6620483bc44)
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