``ext4_xattr_ibody_header`` that is 4 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
``struct ext4_xattr_header``, which is 32 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Attributes stored inside an inode do not need be stored in sorted order.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
the key name. Here is a map of name index values to key prefixes:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Name Index
(crc32c as of October 2013) unless noted otherwise.
.. list-table::
- :widths: 1 1 4
+ :widths: 20 8 50
:header-rows: 1
* - Metadata
``dirent.rec_len`` to know for sure.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
``dirent.rec_len`` to know for sure.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The directory file type is one of the following values:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
``struct ext4_dir_entry_tail``:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
of a data block:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The directory hash is one of the following values:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
also the full length of a data block:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The dx\_tail structure is 8 bytes long and looks like this:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The block group descriptor is laid out in ``struct ext4_group_desc``.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Block group flags can be any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
which is 12 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
recorded as ``struct ext4_extent_idx``, and are 12 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
and are also 12 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
``struct ext4_extent_tail`` is 4 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The inode table entry is laid out in ``struct ext4_inode``.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
+ :class: longtable
* - Offset
- Size
The ``i_mode`` value is a combination of the following flags:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
The ``i_flags`` field is a combination of these values:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
Linux:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Hurd:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Masix:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Linux:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Hurd:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Masix:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
Generally speaking, the journal has this format:
.. list-table::
- :widths: 1 1 78
+ :widths: 16 48 16
:header-rows: 1
* - Superblock
superblock.
.. list-table::
- :widths: 1 1 1 1 76
+ :widths: 12 12 12 32 12
:header-rows: 1
* - 1024 bytes of padding
``struct journal_header_s``:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The journal block type can be any one of:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
which is 1024 bytes long:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The journal compat features are any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
The journal incompat features are any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
most likely choices.
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
Descriptor blocks consume at least 36 bytes, but use a full block:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
following. The size is 16 or 32 bytes.
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The journal tag flags are any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
following. The size is 8, 12, 24, or 28 bytes:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
``struct jbd2_journal_block_tail``, which looks like this:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
length, but use a full block:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
block is a ``struct jbd2_journal_revoke_tail``, which has this format:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
bytes long (but uses a full block):
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The MMP structure (``struct mmp_struct``) is as follows:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 12 20 40
:header-rows: 1
* - Offset
ext4 reserves some inode for special features, as follows:
.. list-table::
- :widths: 1 79
+ :widths: 6 70
:header-rows: 1
* - inode Number
``struct ext4_super_block``:
.. list-table::
- :widths: 1 1 1 77
+ :widths: 8 8 24 40
:header-rows: 1
* - Offset
The superblock state is some combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The superblock error policy is one of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The filesystem creator is one of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The superblock revision is one of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
the following:
.. list-table::
- :widths: 1 79
+ :widths: 16 64
:header-rows: 1
* - Value
The ``s_def_hash_version`` field is one of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The ``s_default_mount_opts`` field is any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The ``s_flags`` field is any combination of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value
The ``s_encrypt_algos`` list can contain any of the following:
.. list-table::
- :widths: 1 79
+ :widths: 8 72
:header-rows: 1
* - Value