hibernate-resume-generator: add a generator for instantiating the resume unit.

hibernate-resume-generator understands resume= kernel command line parameter
and instantiates the systemd-resume@.service accordingly if it is passed.

This enables resume from hibernation using device specified on the kernel
command line, and it may be specified either as "/dev/disk/by-foo/bar"
or "FOO=bar", not only "/dev/sdXY" which is understood by the in-kernel
implementation.

So now resume= is brought on par with root= in terms of possible ways to
specify a device.

2 files changed, 106 insertions, 1 deletions

diff --git a/man/kernel-command-line.xml b/man/kernel-command-line.xml
index 36428aaa9..d872e6d5b 100644
--- a/man/kernel-command-line.xml
+++ b/man/kernel-command-line.xml
@@ -351,6 +351,17 @@
                                 </listitem>
                         </varlistentry>
 
+                        <varlistentry>
+                                <term><varname>resume=</varname></term>
+
+                                <listitem>
+                                        <para>Enables resume from hibernation
+                                        using the specified device.
+                                        All <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-like
+                                        pathes are supported. For details, see
+                                        <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
+                                </listitem>
+                        </varlistentry>
                 </variablelist>
 
         </refsect1>
@@ -373,7 +384,8 @@
                           <citerefentry><refentrytitle>systemd-gpt-auto-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd-modules-load.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd-backlight@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
-                          <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>systemd-rfkill@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                   </para>
         </refsect1>
 
diff --git a/man/systemd-hibernate-resume-generator.xml b/man/systemd-hibernate-resume-generator.xml
new file mode 100644
index 000000000..1a4b99ced
--- /dev/null
+++ b/man/systemd-hibernate-resume-generator.xml
@@ -0,0 +1,93 @@
+<?xml version="1.0"?>
+<!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<!--
+  This file is part of systemd.
+
+  Copyright 2014 Ivan Shapovalov
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+<refentry id="systemd-hibernate-resume-generator">
+
+        <refentryinfo>
+                <title>systemd-hibernate-resume-generator</title>
+                <productname>systemd</productname>
+
+                <authorgroup>
+                        <author>
+                                <contrib>Developer</contrib>
+                                <firstname>Ivan</firstname>
+                                <surname>Shapovalov</surname>
+                                <email>intelfx100@gmail.com</email>
+                        </author>
+                </authorgroup>
+        </refentryinfo>
+
+        <refmeta>
+                <refentrytitle>systemd-hibernate-resume-generator</refentrytitle>
+                <manvolnum>8</manvolnum>
+        </refmeta>
+
+        <refnamediv>
+                <refname>systemd-hibernate-resume-generator</refname>
+                <refpurpose>Unit generator for resume= kernel parameter</refpurpose>
+        </refnamediv>
+
+        <refsynopsisdiv>
+                <para><filename>/usr/lib/systemd/system-generators/systemd-hibernate-resume-generator</filename></para>
+        </refsynopsisdiv>
+
+        <refsect1>
+                <title>Description</title>
+
+                <para><filename>systemd-hibernate-resume-generator</filename> is
+                a generator that instantiates
+                <citerefentry><refentrytitle>systemd-hibernate-resume@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                unit according to the value of <option>resume=</option>
+                parameter specified on the kernel command line.</para>
+        </refsect1>
+
+        <refsect1>
+                <title>Kernel Command Line</title>
+
+                <para><filename>systemd-hibernate-resume-generator</filename> understands
+                the following kernel command line parameters:</para>
+
+                <variablelist class='kernel-commandline-options'>
+
+                        <varlistentry>
+                                <term><varname>resume=</varname></term>
+
+                                <listitem><para>Takes a path to the resume
+                                device. Both persistent block device pathes like
+                                <filename>/dev/disk/by-foo/bar</filename> and
+                                <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>-style
+                                specifiers like <literal>FOO=bar</literal>
+                                are supported.</para></listitem>
+                        </varlistentry>
+
+                </variablelist>
+        </refsect1>
+
+        <refsect1>
+                <title>See Also</title>
+                <para>
+                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>systemd-hibernate-resume@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+                </para>
+        </refsect1>
+
+</refentry>