84 lines
3.9 KiB
HTML
84 lines
3.9 KiB
HTML
<!-- X-URL: http://step.polymtl.ca/~ldd/ext2fs/ext2fs_1.html -->
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<!-- This HTML file has been created by texi2html 1.29
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from ext2fs.texi on 3 August 1994 -->
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<TITLE>Analysis of the Ext2fs structure - Introduction</TITLE>
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<P>Go to the <A HREF="ext2fs_2.html">next</A> section.<P>
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<P>
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Copyright (C) 1994 Louis-Dominique Dubeau.
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<P>
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You may without charge, royalty or other payment, copy and distribute
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copies of this work and derivative works of this work in source or
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binary form provided that:
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<P>
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(1) you appropriately publish on each copy an appropriate copyright
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notice; (2) faithfully reproduce all prior copyright notices included in
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the original work (you may add your own copyright notice); and (3) agree
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to indemnify and hold all prior authors, copyright holders and licensors
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of the work harmless from and against all damages arising from the use
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of the work.
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<P>
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You may distribute sources of derivative works of the work provided
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that:
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<P>
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(1) (a) all source files of the original work that have been modified,
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(b) all source files of the derivative work that contain any party of the
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original work, and (c) all source files of the derivative work that are
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necessary to compile, link and run the derivative work without
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unresolved external calls and with the same functionality of the
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original work ("Necessary Sources") carry a prominent notice explaining
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the nature and date of the modification and/or creation. You are
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encouraged to make the Necessary Sources available under this license in
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EXCEPT AS OTHERWISE RESTRICTED BY LAW, THIS WORK IS PROVIDED WITHOUT ANY
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EXPRESS OR IMPLIED WARRANTIES OF ANY KIND, INCLUDING BUT NOT LIMITED TO,
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ANY IMPLIED WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE,
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MERCHANTABILITY OR TITLE. EXCEPT AS OTHERWISE PROVIDED BY LAW, NO
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AUTHOR, COPYRIGHT HOLDER OR LICENSOR SHALL BE LIABLE TO YOU FOR DAMAGES
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OF ANY KIND, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
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<P>
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<H1><A NAME="SEC1" HREF="ext2fs_toc.html#SEC1">Introduction</A></H1>
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<P>
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This document has been written by Louis-Dominique Dubeau. It contains
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an analysis of the structure of the Second Extended File System and is
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based on a study of the Linux kernel source files. This document does
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not contain specifications written by the Ext2fs development team.
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<P>
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Ext2fs was designed by
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R<EFBFBD>my Card <A NAME="FOOT1" HREF="ext2fs_foot.html#FOOT1">(1)</A>
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as an extensible and powerful file system for Linux. It is also the most
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successful file system so far in the Linux community.
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<P>
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The first Linux file system was Minixfs: a file system originally
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developed for the Minix operating system. This file system had many
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disadvantages. Among them was: the 64MB limit on partitions, the 14
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characters limit on file names and no built in extensibility.
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<P>
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To overcome those problems,
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R<EFBFBD>my Card
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wrote extfs. This file system was mostly based upon the original Minixfs
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code and implementation. However, it removed the 64MB size limit on
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partitions, and increased the file name size limit to 255 characters.
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<P>
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In his quest for the perfect file system,
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R<EFBFBD>my
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was still unsatisfied. So he decided to write an brand new file system:
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ext2fs. This file system not only has the advantages of extfs but also
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provides a better space allocation management, allows the use of special
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flags for file management, the use of access control lists and is
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extensible.
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<P>
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Will someday
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R<EFBFBD>my
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come up with ext3fs? Who knows? However, in the meantime ext2fs is
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<STRONG>the</STRONG> de-facto standard Linux file system. This document describes
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the physical layout of an ext2 file system on disk and the management
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policies that every ext2 file system managers should implement. The
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information in this document is accurate as of version 0.5 of ext2fs
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(Linux kernel version 1.0). The information about access control lists
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is not included because no implementation of ext2fs enforce them anyway.
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<P>
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<P>Go to the <A HREF="ext2fs_2.html">next</A> section.<P>
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