source: postlfs/filesystems/btrfs-progs.xml@ 5a80bacd

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
  <!ENTITY % general-entities SYSTEM "../../general.ent">
  %general-entities;

  <!ENTITY btrfs-progs-download-http "&kernel-dl;/linux/kernel/people/kdave/btrfs-progs/btrfs-progs-v&btrfs-progs-version;.tar.xz">
  <!ENTITY btrfs-progs-download-ftp  " ">
  <!ENTITY btrfs-progs-md5sum        "0eacc7c73c4f086fa10e4bb2fd3f6739">
  <!ENTITY btrfs-progs-size          "2.5 MB">
  <!ENTITY btrfs-progs-buildsize     "65 MB (transient files created during tests need up to 10 GB)">
  <!ENTITY btrfs-progs-time          "0.3 SBU (with parallelism=4; add 3.6 SBU for tests, up to 14 SBU on slow disks)">
]>

<sect1 id="btrfs-progs" xreflabel="btrfs-progs-&btrfs-progs-version;">
  <?dbhtml filename="btrfs-progs.html"?>


  <title>btrfs-progs-&btrfs-progs-version;</title>

  <indexterm zone="btrfs-progs">
    <primary sortas="a-btrfs-progs">btrfs-progs</primary>
  </indexterm>

  <sect2 role="package">
    <title>Introduction to btrfs-progs</title>

    <para>
      The <application>btrfs-progs</application> package contains
      administration and debugging tools for the B-tree file system (btrfs).
    </para>

    &lfs121_checked;

    <bridgehead renderas="sect3">Package Information</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Download (HTTP): <ulink url="&btrfs-progs-download-http;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download (FTP): <ulink url="&btrfs-progs-download-ftp;"/>
        </para>
      </listitem>
      <listitem>
        <para>
          Download MD5 sum: &btrfs-progs-md5sum;
        </para>
      </listitem>
      <listitem>
        <para>
          Download size: &btrfs-progs-size;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated disk space required: &btrfs-progs-buildsize;
        </para>
      </listitem>
      <listitem>
        <para>
          Estimated build time: &btrfs-progs-time;
        </para>
      </listitem>
    </itemizedlist>
<!--
<bridgehead renderas="sect3">Additional Downloads</bridgehead>
    <itemizedlist spacing="compact">
      <listitem>
        <para>
          Required patch if building with linux kernel headers version
          before 5.12:
          <ulink url="&patch-root;/btrfs-progs-&btrfs-progs-version;-headers_fix-1.patch"/>
        </para>
      </listitem>
    </itemizedlist>
-->
    <bridgehead renderas="sect3">Btrfs-progs Dependencies</bridgehead>

    <bridgehead renderas="sect4">Required</bridgehead>
    <para role="required">
      <xref linkend="lzo"/>
    </para>
    <!-- In v6.2.1 (and maybe previous), sphinx is required for the doc
    <bridgehead renderas="sect4">Recommended</bridgehead>
    <para role="recommended">
      <xref linkend="asciidoc"/> (or <xref role="nodep" linkend="asciidoctor"/>)
      and <xref linkend="xmlto"/> (both required to generate man pages)
    </para>
    -->
    <bridgehead renderas="sect4">Optional</bridgehead>
    <para role="optional">
      <xref linkend="lvm2"/> (<command>dmsetup</command> is used in tests),
      <xref linkend="sphinx"/> and <xref linkend="sphinx_rtd_theme"/>
      (required to build documentation), and
      <ulink 
        url='https://mirrors.edge.kernel.org/pub/linux/kernel/people/jeffm/reiserfsprogs/'>
        reiserfsprogs</ulink> (for tests).

    </para>


  </sect2>

  <sect2 role="kernel" id="btrfs-progs-kernel">
    <title>Kernel Configuration</title>

    <para>
      Enable the following option in the kernel configuration
      and recompile the kernel:
    </para>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="btrfs-progs-kernel.xml"/>

    <para>
      In addition to the above and to the options required for
      <xref linkend="lvm2"/>, the following
      options must be set for running tests. The options marked
      as empty should <emphasis>not</emphasis> be selected because they 
      are for developers  and make some tests fail.
    </para>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="btrfs-progs-test-kernel.xml"/>

    <indexterm zone="btrfs-progs btrfs-progs-kernel">
      <primary sortas="d-btrfs-progs">BTRFS Programs</primary>
    </indexterm>

  </sect2>

  <sect2 role="installation">
    <title>Installation of btrfs-progs</title>

    <para>
      Install <application>btrfs-progs</application> by running the following
      commands:
    </para>

<screen><userinput>./configure --prefix=/usr           \
            --disable-static        \
            --disable-documentation &amp;&amp;
make</userinput></screen>

    <note>
      <para>
        Some tests require grep built with perl regular expressions. To
        obtain this, rebuild grep with the LFS Chapter 8 instructions after
        installing <xref linkend="pcre2"/>.
      </para>
    </note>
<!-- Keeping this for now, but it seems that calling "make test" is
     simpler and does the same thing -->
    <para>
      Before running tests, build a support program:
    </para>

<screen remap="test"><userinput>make fssum</userinput></screen>

    <para>
      First, fix one test and disable another that is known to fail:
    </para>

<screen role="root" remap="test"><userinput>sed -i 's/ mount/&amp; -o nodiscard/' tests/misc-tests/004-shrink-fs/test.sh &amp;&amp;
mv tests/misc-tests/041-subvolume-delete-during-send/test.sh \
   tests/misc-tests/041-subvolume-delete-during-send/test.sh.skip</userinput></screen>

    <para>
      To test the results, issue (as the &root; user):
    </para>

<screen role="root" remap="test"><userinput>pushd tests
   ./fsck-tests.sh
   ./mkfs-tests.sh
   ./cli-tests.sh
   ./convert-tests.sh
   ./misc-tests.sh
   ./fuzz-tests.sh
popd</userinput></screen>

<!-- Template for failed test removal:
      the other ones to run:
    </para>

<screen remap="test"><userinput>mv tests/fsck-tests/012-leaf-corruption/test.sh{,.broken}</userinput></screen>
Substitute your test failure with the one above.
    <para>
      To test the results, run (as the
      <systemitem class="username">root</systemitem> user):
    </para>

<screen role="root" remap="test"><userinput>make -j1 -k test</userinput></screen>
-->
    <note>
      <para>
        If the above mentioned kernel options are not enabled, some tests
        fail, and prevent all the remaining tests from running because the test
        disk image is not cleanly unmounted. Also make sure that the btrfs
        kernel module is loaded.
      </para>
    </note>

<!-- 6.8.1 - all tests went pretty fine, including the previously commented
             convert-tests and the other two mentioned tests.
    <para>
      The convert-tests scripts are known to fail.
      Tests 004-shrink-fs and 062-fi-show-raw-dm-all-devices in the misc-tests 
      are known to fail.
    </para>
-->
    <para>
      Install the package as the &root; user:
    </para>

<screen role="root"><userinput>make install</userinput></screen>

    <para>
      If you have passed <parameter>--disable-documentation</parameter> to
      <command>configure</command> and you need the manual pages, install them
      by running, as the &root; user:
    </para>

<screen role="root"><userinput>for i in 5 8; do
   install Documentation/*.$i /usr/share/man/man$i
done</userinput></screen>

  </sect2>

  <sect2 role="commands">
    <title>Command Explanations</title>

    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
      href="../../xincludes/static-libraries.xml"/>

    <para>
      <parameter>--disable-documentation</parameter>: This switch
      disables rebuilding the manual pages, because it requires
      <xref linkend="sphinx"/>.
    </para>
<!--
    <para>
      <command>sed 's/,orphan_file//" ...</command>: In this version of
      <application>btrfs-progs</application>, the
      <command>btrfs-convert</command> program produces a btrfs filesystem
      containing errors if converting from an ext4 filesystem created
      with the <quote>orphan_file</quote> feature. This command creates
      a custom configuration file that prevents creating a filesystem
      with this feature.
    </para>
-->
    <!--
    <para>
      <command>ln -s ... /usr/lib/libbtrfs.so</command>: Creates a
      symbolic link in the directory where it is expected.
    </para>

    <para>
      <command>rm /lib/libbtrfs.{a,so}</command>: Removes unneeded
      library entries.
    </para>
-->
  </sect2>
<!--
  <sect2 role="using" id="using-btrfs-convert">
    <title>Using the btrfs-convert Program</title>

    <para>
      This version of <application>btrfs-progs</application> does not convert
      correctly ext4 filesystems to btrfs if the ext4
      <option>orphan_file</option> feature is turned on. If you happen to
      convert such a filesystem, you need to first run:
    </para>

<screen role="nodump"><userinput>tune2fs -O ^orphan_file <replaceable>/dev/sdxx</replaceable></userinput></screen>

    <para>
      where <filename>/dev/sdxx</filename> is the partition of the filesystem
      you want to convert.
    </para>
  </sect2>
-->

  <sect2 role="content">
    <title>Contents</title>

    <segmentedlist>
      <segtitle>Installed Programs</segtitle>
      <segtitle>Installed Libraries</segtitle>
      <segtitle>Installed Directories</segtitle>

      <seglistitem>
        <seg>
          btrfs,
          btrfs-convert,
          btrfs-find-root,
          btrfs-image,
          btrfs-map-logical,
          btrfs-select-super,
          btrfsck (link to btrfs),
          btrfstune,
          fsck.btrfs, and
          mkfs.btrfs
        </seg>

        <seg>
          libbtrfs.so and
          libbtrfsutil.so
        </seg>

        <seg>/usr/include/btrfs</seg>
      </seglistitem>
    </segmentedlist>

    <variablelist>
      <bridgehead renderas="sect3">Short Descriptions</bridgehead>
      <?dbfo list-presentation="list"?>
      <?dbhtml list-presentation="table"?>

      <varlistentry id="btrfs-prog">
        <term><command>btrfs</command></term>
        <listitem>
          <para>
            is the main interface into btrfs filesystem operations
          </para>
          <indexterm zone="btrfs-progs btrfs-prog">
            <primary sortas="b-btrfs">btrfs</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="btrfs-convert">
        <term><command>btrfs-convert</command></term>
        <listitem>
          <para>
            converts from an ext2/3/4 or reiserfs filesystem to btrfs <!--(see
            <xref linkend="using-btrfs-convert"/> above)-->
          </para>
          <indexterm zone="btrfs-progs btrfs-convert">
            <primary sortas="b-btrfs-convert">btrfs-convert</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="btrfs-find-root">
        <term><command>btrfs-find-root</command></term>
        <listitem>
          <para>
            is a filter to find btrfs root
          </para>
          <indexterm zone="btrfs-progs btrfs-find-root">
            <primary sortas="b-btrfs-find-root">btrfs-find-root</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="btrfs-map-logical">
        <term><command>btrfs-map-logical</command></term>
        <listitem>
          <para>
            maps btrfs logical extent to physical extent
          </para>
          <indexterm zone="btrfs-progs btrfs-map-logical">
            <primary sortas="b-btrfs-map-logical">btrfs-map-logical</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="btrfs-select-super">
        <term><command>btrfs-select-super</command></term>
        <listitem>
          <para>
            overwrites the primary superblock with a backup copy
          </para>
          <indexterm zone="btrfs-progs btrfs-select-super">
            <primary sortas="b-btrfs-select-super">btrfs-select-super</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="btrfstune">
        <term><command>btrfstune</command></term>
        <listitem>
          <para>
            tunes various filesystem parameters
          </para>
          <indexterm zone="btrfs-progs btrfstune">
            <primary sortas="b-btrfstune">btrfstune</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="fsck.btrfs">
        <term><command>fsck.btrfs</command></term>
        <listitem>
          <para>
            does nothing, but is present for consistency with fstab
          </para>
          <indexterm zone="btrfs-progs fsck.btrfs">
            <primary sortas="b-fsck.btrfs">fsck.btrfs</primary>
          </indexterm>
        </listitem>
      </varlistentry>

      <varlistentry id="mkfs.btrfs">
        <term><command>mkfs.btrfs</command></term>
        <listitem>
          <para>
            creates a btrfs file system
          </para>
          <indexterm zone="btrfs-progs mkfs.btrfs">
            <primary sortas="b-mkfs.btrfs">mkfs.btrfs</primary>
          </indexterm>
        </listitem>
      </varlistentry>

    </variablelist>

  </sect2>

</sect1>