linux/Documentation/filesystems/ext4/special_inodes.rst

.. SPDX-License-Identifier: GPL-2.0

Special inodes
--------------

ext4 reserves some inode for special features, as follows:

.. list-table::
   :widths: 6 70
   :header-rows: 1

   * - inode Number
     - Purpose
   * - 0
     - Doesn't exist; there is no inode 0.
   * - 1
     - List of defective blocks.
   * - 2
     - Root directory.
   * - 3
     - User quota.
   * - 4
     - Group quota.
   * - 5
     - Boot loader.
   * - 6
     - Undelete directory.
   * - 7
     - Reserved group descriptors inode. (“resize inode”)
   * - 8
     - Journal inode.
   * - 9
     - The “exclude” inode, for snapshots(?)
   * - 10
     - Replica inode, used for some non-upstream feature?
   * - 11
     - Traditional first non-reserved inode. Usually this is the lost+found directory. See s\_first\_ino in the superblock.
ext4: import high level design chapter from wiki page Import the chapter about high level design from the on-disk format wiki page into the kernel documentation. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> 2018-07-29 22:38:00 +03:00			`.. SPDX-License-Identifier: GPL-2.0`

			`Special inodes`
			`--------------`

			`ext4 reserves some inode for special features, as follows:`

			`.. list-table::`
docs: fix ext4 documentation table formatting problems It turns out that the latex table formatters lay out table columns with the exact proportional widths given in the table metadata, even if text overflows outside the box. This was not caught during the initial import because the HTML renderers are smart enough to fudge the table. Fix the table column width formatting problems in the data structures and algorithms documentation so that we don't have squashed columns. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> 2018-10-03 05:43:40 +03:00			`:widths: 6 70`
ext4: import high level design chapter from wiki page Import the chapter about high level design from the on-disk format wiki page into the kernel documentation. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> 2018-07-29 22:38:00 +03:00			`:header-rows: 1`

			`* - inode Number`
			`- Purpose`
			`* - 0`
			`- Doesn't exist; there is no inode 0.`
			`* - 1`
			`- List of defective blocks.`
			`* - 2`
			`- Root directory.`
			`* - 3`
			`- User quota.`
			`* - 4`
			`- Group quota.`
			`* - 5`
			`- Boot loader.`
			`* - 6`
			`- Undelete directory.`
			`* - 7`
			`- Reserved group descriptors inode. (“resize inode”)`
			`* - 8`
			`- Journal inode.`
			`* - 9`
			`- The “exclude” inode, for snapshots(?)`
			`* - 10`
			`- Replica inode, used for some non-upstream feature?`
			`* - 11`
			`- Traditional first non-reserved inode. Usually this is the lost+found directory. See s\_first\_ino in the superblock.`