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diff --git a/Documentation/filesystems/ext4/ondisk/about.rst b/Documentation/filesystems/ext4/ondisk/about.rst deleted file mode 100644 index 0aadba052264..000000000000 --- a/Documentation/filesystems/ext4/ondisk/about.rst +++ /dev/null @@ -1,44 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -About this Book -=============== - -This document attempts to describe the on-disk format for ext4 -filesystems. The same general ideas should apply to ext2/3 filesystems -as well, though they do not support all the features that ext4 supports, -and the fields will be shorter. - -**NOTE**: This is a work in progress, based on notes that the author -(djwong) made while picking apart a filesystem by hand. The data -structure definitions should be current as of Linux 4.18 and -e2fsprogs-1.44. All comments and corrections are welcome, since there is -undoubtedly plenty of lore that might not be reflected in freshly -created demonstration filesystems. - -License -------- -This book is licensed under the terms of the GNU Public License, v2. - -Terminology ------------ - -ext4 divides a storage device into an array of logical blocks both to -reduce bookkeeping overhead and to increase throughput by forcing larger -transfer sizes. Generally, the block size will be 4KiB (the same size as -pages on x86 and the block layer's default block size), though the -actual size is calculated as 2 ^ (10 + ``sb.s_log_block_size``) bytes. -Throughout this document, disk locations are given in terms of these -logical blocks, not raw LBAs, and not 1024-byte blocks. For the sake of -convenience, the logical block size will be referred to as -``$block_size`` throughout the rest of the document. - -When referenced in ``preformatted text`` blocks, ``sb`` refers to fields -in the super block, and ``inode`` refers to fields in an inode table -entry. - -Other References ----------------- - -Also see http://www.nongnu.org/ext2-doc/ for quite a collection of -information about ext2/3. Here's another old reference: -http://wiki.osdev.org/Ext2 |