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+.. SPDX-License-Identifier: GPL-2.0
+
+Special inodes
+--------------
+
+ext4 reserves some inode for special features, as follows:
+
+.. list-table::
+ :widths: 1 79
+ :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.
+