__ __ __ __ _____ _ _ _____ _ _ _ | \/ | \ \ / / | __ \ (_) | | / ____| | | | | | \ / |_ __\ V / | |__) | __ ___ ____ _| |_ ___ | (___ | |__ ___| | | | |\/| | '__|> < | ___/ '__| \ \ / / _` | __/ _ \ \___ \| '_ \ / _ \ | | | | | | |_ / . \ | | | | | |\ V / (_| | || __/ ____) | | | | __/ | | |_| |_|_(_)_/ \_\ |_| |_| |_| \_/ \__,_|\__\___| |_____/|_| |_|\___V 2.1 if you need WebShell for Seo everyday contact me on Telegram Telegram Address : @jackleetFor_More_Tools:
<!DOCTYPE html>
<html lang="en" data-content_root="../../">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="viewport" content="width=device-width, initial-scale=1" />
<title>3.3. Block and inode Bitmaps — The Linux Kernel documentation</title>
<link rel="stylesheet" type="text/css" href="../../_static/pygments.css?v=fa44fd50" />
<link rel="stylesheet" type="text/css" href="../../_static/alabaster.css?v=3918102e" />
<script src="../../_static/documentation_options.js?v=5929fcd5"></script>
<script src="../../_static/doctools.js?v=9bcbadda"></script>
<script src="../../_static/sphinx_highlight.js?v=dc90522c"></script>
<link rel="index" title="Index" href="../../genindex.html" />
<link rel="search" title="Search" href="../../search.html" />
<link rel="next" title="3.4. Inode Table" href="inode_table.html" />
<link rel="prev" title="3.2. Block Group Descriptors" href="group_descr.html" />
<link rel="stylesheet" href="../../_static/custom.css" type="text/css" />
</head><body>
<div class="document">
<div class="sphinxsidebar" role="navigation" aria-label="Main">
<div class="sphinxsidebarwrapper">
<p class="logo"><a href="../../index.html">
<img class="logo" src="../../_static/logo.svg" alt="Logo of The Linux Kernel"/>
</a></p>
<h1 class="logo"><a href="../../index.html">The Linux Kernel</a></h1>
<p class="blurb">6.18.50</p>
<search id="searchbox" style="display: none" role="search">
<h3 id="searchlabel">Quick search</h3>
<div class="searchformwrapper">
<form class="search" action="../../search.html" method="get">
<input type="text" name="q" aria-labelledby="searchlabel" autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>
<input type="submit" value="Go" />
</form>
</div>
</search>
<script>document.getElementById('searchbox').style.display = "block"</script>
<p>
<h3 class="kernel-toc-contents">Contents</h3>
<input type="checkbox" class="kernel-toc-toggle" id = "kernel-toc-toggle" checked>
<label class="kernel-toc-title" for="kernel-toc-toggle"></label>
<div class="kerneltoc" id="kerneltoc">
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../process/development-process.html">Development process</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../process/submitting-patches.html">Submitting patches</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../process/code-of-conduct.html">Code of conduct</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../maintainer/index.html">Maintainer handbook</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../process/index.html">All development-process docs</a></li>
</ul>
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="../../core-api/index.html">Core API</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../driver-api/index.html">Driver APIs</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="../../subsystem-apis.html">Subsystems</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="../../subsystem-apis.html#core-subsystems">Core subsystems</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../subsystem-apis.html#human-interfaces">Human interfaces</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../subsystem-apis.html#networking-interfaces">Networking interfaces</a></li>
<li class="toctree-l2 current"><a class="reference internal" href="../../subsystem-apis.html#storage-interfaces">Storage interfaces</a><ul class="current">
<li class="toctree-l3 current"><a class="reference internal" href="../index.html">Filesystems in the Linux kernel</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../block/index.html">Block</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../cdrom/index.html">CD-ROM</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../scsi/index.html">SCSI Subsystem</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../target/index.html">TCM Virtual Device</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../nvme/index.html">NVMe Subsystem</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="../../subsystem-apis.html#other-subsystems">Other subsystems</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="../../locking/index.html">Locking</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../process/license-rules.html">Licensing rules</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../doc-guide/index.html">Writing documentation</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../dev-tools/index.html">Development tools</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../dev-tools/testing-overview.html">Testing guide</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../kernel-hacking/index.html">Hacking guide</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../trace/index.html">Tracing</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../fault-injection/index.html">Fault injection</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../livepatch/index.html">Livepatching</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../rust/index.html">Rust</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../admin-guide/index.html">Administration</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../kbuild/index.html">Build system</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../admin-guide/reporting-issues.html">Reporting issues</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../tools/index.html">Userspace tools</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../userspace-api/index.html">Userspace API</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../firmware-guide/index.html">Firmware</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../devicetree/index.html">Firmware and Devicetree</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../arch/index.html">CPU architectures</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../staging/index.html">Unsorted documentation</a></li>
</ul>
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../translations/index.html">Translations</a></li>
</ul>
</div>
<script type="text/javascript"> <!--
var sbar = document.getElementsByClassName("sphinxsidebar")[0];
let currents = document.getElementsByClassName("current")
if (currents.length) {
sbar.scrollTop = currents[currents.length - 1].offsetTop;
}
--> </script>
<div role="note" aria-label="source link">
<h3>This Page</h3>
<ul class="this-page-menu">
<li><a href="../../_sources/filesystems/ext4/bitmaps.rst.txt"
rel="nofollow">Show Source</a></li>
</ul>
</div>
</div>
</div>
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="block-and-inode-bitmaps">
<h1><span class="section-number">3.3. </span>Block and inode Bitmaps<a class="headerlink" href="#block-and-inode-bitmaps" title="Link to this heading">¶</a></h1>
<p>The data block bitmap tracks the usage of data blocks within the block
group.</p>
<p>The inode bitmap records which entries in the inode table are in use.</p>
<p>As with most bitmaps, one bit represents the usage status of one data
block or inode table entry. This implies a block group size of 8 *
number_of_bytes_in_a_logical_block.</p>
<p>NOTE: If <code class="docutils literal notranslate"><span class="pre">BLOCK_UNINIT</span></code> is set for a given block group, various parts
of the kernel and e2fsprogs code pretends that the block bitmap contains
zeros (i.e. all blocks in the group are free). However, it is not
necessarily the case that no blocks are in use -- if <code class="docutils literal notranslate"><span class="pre">meta_bg</span></code> is set,
the bitmaps and group descriptor live inside the group. Unfortunately,
<code class="xref c c-func broken_xref docutils literal notranslate"><span class="pre">ext2fs_test_block_bitmap2()</span></code> will return ‘0’ for those locations,
which produces confusing debugfs output.</p>
</section>
</div>
</div>
</div>
<div class="clearer"></div>
</div>
<div class="footer">
©The kernel development community.
|
Powered by <a href="https://www.sphinx-doc.org/">Sphinx 8.1.3</a>
& <a href="https://alabaster.readthedocs.io">Alabaster 0.7.16</a>
|
<a href="../../_sources/filesystems/ext4/bitmaps.rst.txt"
rel="nofollow">Page source</a>
</div>
</body>
</html>| Name | Type | Size | Permission | Actions |
|---|---|---|---|---|
| about.html | File | 10.74 KB | 0644 |
|
| allocators.html | File | 11.32 KB | 0644 |
|
| atomic_writes.html | File | 23.38 KB | 0644 |
|
| attributes.html | File | 17.68 KB | 0644 |
|
| bigalloc.html | File | 9.84 KB | 0644 |
|
| bitmaps.html | File | 9.17 KB | 0644 |
|
| blockgroup.html | File | 16.02 KB | 0644 |
|
| blockmap.html | File | 10.92 KB | 0644 |
|
| blocks.html | File | 13.03 KB | 0644 |
|
| checksums.html | File | 11.76 KB | 0644 |
|
| directory.html | File | 30.85 KB | 0644 |
|
| dynamic.html | File | 10.05 KB | 0644 |
|
| eainode.html | File | 9.04 KB | 0644 |
|
| globals.html | File | 10.3 KB | 0644 |
|
| group_descr.html | File | 15.66 KB | 0644 |
|
| ifork.html | File | 23.04 KB | 0644 |
|
| index.html | File | 11.11 KB | 0644 |
|
| inlinedata.html | File | 10.18 KB | 0644 |
|
| inode_table.html | File | 8.43 KB | 0644 |
|
| inodes.html | File | 37.98 KB | 0644 |
|
| journal.html | File | 45.16 KB | 0644 |
|
| mmp.html | File | 11.48 KB | 0644 |
|
| orphan.html | File | 10.48 KB | 0644 |
|
| overview.html | File | 12.11 KB | 0644 |
|
| special_inodes.html | File | 10.42 KB | 0644 |
|
| super.html | File | 44.31 KB | 0644 |
|
| verity.html | File | 10.07 KB | 0644 |
|