From 42483a747489ff46aed3588b78bf4b9480dbeaf7 Mon Sep 17 00:00:00 2001

From: Ivan Shapovalov <intelfx100@gmail.com>

Date: Wed, 27 Aug 2014 00:17:44 +0400

Subject: [PATCH] hibernate-resume: add a tool to write a device node's

 major:minor to /sys/power/resume.

This can be used to initiate a resume from hibernation by path to a swap

device containing the hibernation image.

The respective templated unit is also added. It is instantiated using

path to the desired resume device.

---

 .gitignore                                 |  1 +

 Makefile-man.am                            |  7 +++

 Makefile.am                                | 17 +++++--

 man/systemd-hibernate-resume@.service.xml  | 81 ++++++++++++++++++++++++++++++

 src/hibernate-resume/Makefile              |  1 +

 src/hibernate-resume/hibernate-resume.c    | 81 ++++++++++++++++++++++++++++++

 units/.gitignore                           |  1 +

 units/systemd-hibernate-resume@.service.in | 20 ++++++++

 8 files changed, 206 insertions(+), 3 deletions(-)

 create mode 100644 man/systemd-hibernate-resume@.service.xml

 create mode 120000 src/hibernate-resume/Makefile

 create mode 100644 src/hibernate-resume/hibernate-resume.c

 create mode 100644 units/systemd-hibernate-resume@.service.in

diff --git a/.gitignore b/.gitignore

index 8189da71f0..0b5608ccf9 100644

--- a/.gitignore

+++ b/.gitignore

@@ -75,6 +75,7 @@

 /systemd-getty-generator

 /systemd-gnome-ask-password-agent

 /systemd-gpt-auto-generator

+/systemd-hibernate-resume

 /systemd-hostnamed

 /systemd-inhibit

 /systemd-initctl

diff --git a/Makefile-man.am b/Makefile-man.am

index 562ecba435..09a10383a9 100644

--- a/Makefile-man.am

+++ b/Makefile-man.am

@@ -70,6 +70,7 @@ MANPAGES += \

 	man/systemd-getty-generator.8 \

 	man/systemd-gpt-auto-generator.8 \

 	man/systemd-halt.service.8 \

+	man/systemd-hibernate-resume@.service.8 \

 	man/systemd-inhibit.1 \

 	man/systemd-initctl.service.8 \

 	man/systemd-journald.service.8 \

@@ -199,6 +200,7 @@ MANPAGES_ALIAS += \

 	man/systemd-firstboot.service.1 \

 	man/systemd-fsck-root.service.8 \

 	man/systemd-fsck.8 \

+	man/systemd-hibernate-resume.8 \

 	man/systemd-hibernate.service.8 \

 	man/systemd-hybrid-sleep.service.8 \

 	man/systemd-initctl.8 \

@@ -305,6 +307,7 @@ man/systemd-ask-password-wall.service.8: man/systemd-ask-password-console.servic

 man/systemd-firstboot.service.1: man/systemd-firstboot.1

 man/systemd-fsck-root.service.8: man/systemd-fsck@.service.8

 man/systemd-fsck.8: man/systemd-fsck@.service.8

+man/systemd-hibernate-resume.8: man/systemd-hibernate-resume@.service.8

 man/systemd-hibernate.service.8: man/systemd-suspend.service.8

 man/systemd-hybrid-sleep.service.8: man/systemd-suspend.service.8

 man/systemd-initctl.8: man/systemd-initctl.service.8

@@ -567,6 +570,9 @@ man/systemd-fsck-root.service.html: man/systemd-fsck@.service.html

 man/systemd-fsck.html: man/systemd-fsck@.service.html

 	$(html-alias)

+man/systemd-hibernate-resume.html: man/systemd-hibernate-resume@.service.html

+	$(html-alias)

+

 man/systemd-hibernate.service.html: man/systemd-suspend.service.html

 	$(html-alias)

@@ -1619,6 +1625,7 @@ EXTRA_DIST += \

 	man/systemd-getty-generator.xml \

 	man/systemd-gpt-auto-generator.xml \

 	man/systemd-halt.service.xml \

+	man/systemd-hibernate-resume@.service.xml \

 	man/systemd-hostnamed.service.xml \

 	man/systemd-inhibit.xml \

 	man/systemd-initctl.service.xml \

diff --git a/Makefile.am b/Makefile.am

index cbf98bdac3..a487caa7bc 100644

--- a/Makefile.am

+++ b/Makefile.am

@@ -378,7 +378,8 @@ rootlibexec_PROGRAMS = \

 	systemd-sleep \

 	systemd-bus-proxyd \

 	systemd-socket-proxyd \

-	systemd-update-done

+	systemd-update-done \

+	systemd-hibernate-resume

 systemgenerator_PROGRAMS = \

 	systemd-getty-generator \

@@ -528,7 +529,8 @@ nodist_systemunit_DATA = \

 	units/initrd-udevadm-cleanup-db.service \

 	units/initrd-switch-root.service \

 	units/systemd-nspawn@.service \

-	units/systemd-update-done.service

+	units/systemd-update-done.service \

+	units/systemd-hibernate-resume@.service

 dist_userunit_DATA = \

 	units/user/basic.target \

@@ -575,7 +577,8 @@ EXTRA_DIST += \

 	units/initrd-udevadm-cleanup-db.service.in \

 	units/initrd-switch-root.service.in \

 	units/systemd-nspawn@.service.in \

-	units/systemd-update-done.service.in

+	units/systemd-update-done.service.in \

+	units/systemd-hibernate-resume@.service.in

 CLEANFILES += \

 	units/console-shell.service.m4 \

@@ -2103,6 +2106,14 @@ systemd_delta_LDADD = \

 	libsystemd-shared.la

 # ------------------------------------------------------------------------------

+systemd_hibernate_resume_SOURCES = \

+	src/hibernate-resume/hibernate-resume.c

+

+systemd_hibernate_resume_LDADD = \

+	libsystemd-internal.la \

+	libsystemd-shared.la

+

+# ------------------------------------------------------------------------------

 systemd_getty_generator_SOURCES = \

 	src/getty-generator/getty-generator.c

diff --git a/man/systemd-hibernate-resume@.service.xml b/man/systemd-hibernate-resume@.service.xml

new file mode 100644

index 0000000000..9b188b0d96

--- /dev/null

+++ b/man/systemd-hibernate-resume@.service.xml

@@ -0,0 +1,81 @@

+

+

+

+

+  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@.service">

+

+        <refentryinfo>

+                <title>systemd-hibernate-resume@.service</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@.service</refentrytitle>

+                <manvolnum>8</manvolnum>

+        </refmeta>

+

+        <refnamediv>

+                <refname>systemd-hibernate-resume@.service</refname>

+                <refname>systemd-hibernate-resume</refname>

+                <refpurpose>Resume from hibernation</refpurpose>

+        </refnamediv>

+

+        <refsynopsisdiv>

+                <para><filename>systemd-hibernate-resume@.service</filename></para>

+                <para><filename>/usr/lib/systemd/systemd-hibernate-resume</filename></para>

+        </refsynopsisdiv>

+

+        <refsect1>

+                <title>Description</title>

+

+                <para><filename>systemd-hibernate-resume@.service</filename> is a

+                service that initiates hibernation resume from a device

+                containing the resume image. It is instantiated for each

+                device that is configured for resuming from.</para>

+

+                <para><filename>systemd-hibernate-resume</filename> only supports

+                the in-kernel hibernation implementation, known as swsusp.

+                Internally, it works by writing the major:minor of specified

+                device node to <filename>/sys/power/resume</filename>.</para>

+

+                <para>Failing to initiate a resume is not an error condition.

+                It may mean that there was no resume image (e. g. if the

+                system has been simply powered off and not hibernated). In

+                such case, the boot is ordinarily continued.</para>

+        </refsect1>

+

+        <refsect1>

+                <title>See Also</title>

+                <para>

+                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,

+                        <citerefentry><refentrytitle>systemd-hibernate-resume-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>

+                </para>

+        </refsect1>

+

+</refentry>

diff --git a/src/hibernate-resume/Makefile b/src/hibernate-resume/Makefile

new file mode 120000

index 0000000000..d0b0e8e008

--- /dev/null

+++ b/src/hibernate-resume/Makefile

@@ -0,0 +1 @@

+../Makefile

\ No newline at end of file

diff --git a/src/hibernate-resume/hibernate-resume.c b/src/hibernate-resume/hibernate-resume.c

new file mode 100644

index 0000000000..8f68f81f9e

--- /dev/null

+++ b/src/hibernate-resume/hibernate-resume.c

@@ -0,0 +1,81 @@

+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

+

+/***

+  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/>.

+***/

+

+#include <stdio.h>

+#include <errno.h>

+#include <sys/types.h>

+#include <sys/stat.h>

+#include <unistd.h>

+

+#include "log.h"

+#include "util.h"

+#include "fileio.h"

+

+int main(int argc, char *argv[]) {

+        struct stat st;

+        const char *device;

+        _cleanup_free_ char *major_minor = NULL;

+        int r;

+

+        if (argc != 2) {

+                log_error("This program expects one argument.");

+                return EXIT_FAILURE;

+        }

+

+        log_set_target(LOG_TARGET_AUTO);

+        log_parse_environment();

+        log_open();

+

+        umask(0022);

+

+        device = argv[1];

+

+        if (stat(device, &st) < 0) {

+                log_error("Failed to stat '%s': %m", device);

+                return EXIT_FAILURE;

+        }

+

+        if (!S_ISBLK(st.st_mode)) {

+                log_error("Resume device '%s' is not a block device.", device);

+                return EXIT_FAILURE;

+        }

+

+        if (asprintf(&major_minor, "%d:%d", major(st.st_rdev), minor(st.st_rdev)) < 0) {

+                log_oom();

+                return EXIT_FAILURE;

+        }

+

+        r = write_string_file("/sys/power/resume", major_minor);

+        if (r < 0) {

+                log_error("Failed to write '%s' to /sys/power/resume: %s", major_minor, strerror(-r));

+                return EXIT_FAILURE;

+        }

+

+        /*

+         * The write above shall not return.

+         *

+         * However, failed resume is a normal condition (may mean that there is

+         * no hibernation image).

+         */

+

+        log_info("Could not resume from '%s' (%s).", device, major_minor);

+        return EXIT_SUCCESS;

+}

diff --git a/units/.gitignore b/units/.gitignore

index d9b60ac0fc..c60f357416 100644

--- a/units/.gitignore

+++ b/units/.gitignore

@@ -54,6 +54,7 @@

 /systemd-reboot.service

 /systemd-remount-fs.service

 /systemd-resolved.service

+/systemd-hibernate-resume@.service

 /systemd-rfkill@.service

 /systemd-shutdownd.service

 /systemd-suspend.service

diff --git a/units/systemd-hibernate-resume@.service.in b/units/systemd-hibernate-resume@.service.in

new file mode 100644

index 0000000000..6db584dc4d

--- /dev/null

+++ b/units/systemd-hibernate-resume@.service.in

@@ -0,0 +1,20 @@

+#  This file is part of systemd.

+#

+#  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.

+

+[Unit]

+Description=Resume from hibernation using device %f

+Documentation=man:systemd-hibernate-resume@.service(8)

+DefaultDependencies=no

+BindsTo=%i.device

+Wants=local-fs-pre.target

+After=%i.device

+Before=local-fs-pre.target systemd-remount-fs.service systemd-fsck-root.service

+ConditionPathExists=/etc/initrd-release

+

+[Service]

+Type=oneshot

+ExecStart=@rootlibexecdir@/systemd-hibernate-resume %f