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| author | Luca Boccassi <luca.boccassi@microsoft.com> | 2022-01-17 02:14:14 +0100 |
|---|---|---|
| committer | Yu Watanabe <watanabe.yu+github@gmail.com> | 2022-01-21 14:53:12 +0100 |
| commit | a07b9926060782ab21decdcb282ea3f39ed4f124 (patch) | |
| tree | ba6fbf3ea52084f9914d9b24fd9229c6a6e798b0 /man/systemd.exec.xml | |
| parent | Merge pull request #22195 from keszybz/more-specifiers (diff) | |
| download | systemd-a07b9926060782ab21decdcb282ea3f39ed4f124.tar.xz systemd-a07b9926060782ab21decdcb282ea3f39ed4f124.zip | |
core: add ExtensionDirectories= setting
Add a new setting that follows the same principle and implementation
as ExtensionImages, but using directories as sources.
It will be used to implement support for extending portable images
with directories, since portable services can already use a directory
as root.
Diffstat (limited to 'man/systemd.exec.xml')
| -rw-r--r-- | man/systemd.exec.xml | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml index 079ff14aea..36a884c9f4 100644 --- a/man/systemd.exec.xml +++ b/man/systemd.exec.xml @@ -459,6 +459,34 @@ <xi:include href="system-only.xml" xpointer="singular"/></listitem> </varlistentry> + + <varlistentry> + <term><varname>ExtensionDirectories=</varname></term> + + <listitem><para>This setting is similar to <varname>BindReadOnlyPaths=</varname> in that it mounts a file + system hierarchy from a directory, but instead of providing a destination path, an overlay will be set + up. This option expects a whitespace separated list of source directories.</para> + + <para>A read-only OverlayFS will be set up on top of <filename>/usr/</filename> and + <filename>/opt/</filename> hierarchies. The order in which the directories are listed will determine + the order in which the overlay is laid down: directories specified first to last will result in overlayfs + layers bottom to top.</para> + + <para>Each directory listed in <varname>ExtensionDirectories=</varname> may be prefixed with <literal>-</literal>, + in which case it will be ignored when its source path does not exist. Any mounts created with this option are + specific to the unit, and are not visible in the host's mount table.</para> + + <para>These settings may be used more than once, each usage appends to the unit's list of directories + paths. If the empty string is assigned, the entire list of mount paths defined prior to this is + reset.</para> + + <para>Each directory must contain a <filename>/usr/lib/extension-release.d/extension-release.IMAGE</filename> + file, with the appropriate metadata which matches <varname>RootImage=</varname>/<varname>RootDirectory=</varname> + or the host. See: + <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para> + + <xi:include href="system-only.xml" xpointer="singular"/></listitem> + </varlistentry> </variablelist> </refsect1> |