systemd: make systemd-fsck run after cloud-init.service

cloud-init.service may write filesystems (fs_setup) or re-partition
(disk_setup) disks.

If systemd-fsck is running on a device while that is occuring
then the partitioning or mkfs might fail due to the device being busy.
Alternatively, the fsck might fail and cause subsequent mount to fail.

LP: #1691489

2 files changed, 6 insertions, 0 deletions

diff --git a/setup.py b/setup.py
index 1197eceb..b1bde43b 100755
--- a/setup.py
+++ b/setup.py
@@ -125,6 +125,7 @@ INITSYS_FILES = {
                 for f in (glob('systemd/*.tmpl') +
                           glob('systemd/*.service') +
                           glob('systemd/*.target')) if is_f(f)],
+    'systemd.fsck-dropin': ['systemd/systemd-fsck@.service.d/cloud-init.conf'],
     'systemd.generators': [f for f in glob('systemd/*-generator') if is_f(f)],
     'upstart': [f for f in glob('upstart/*') if is_f(f)],
 }
@@ -134,6 +135,9 @@ INITSYS_ROOTS = {
     'sysvinit_deb': 'etc/init.d',
     'sysvinit_openrc': 'etc/init.d',
     'systemd': pkg_config_read('systemd', 'systemdsystemunitdir'),
+    'systemd.fsck-dropin': (
+        os.path.sep.join([pkg_config_read('systemd', 'systemdsystemunitdir'),
+                          'systemd-fsck@.service.d'])),
     'systemd.generators': pkg_config_read('systemd',
                                           'systemdsystemgeneratordir'),
     'upstart': 'etc/init/',
diff --git a/systemd/systemd-fsck@.service.d/cloud-init.conf b/systemd/systemd-fsck@.service.d/cloud-init.conf
new file mode 100644
index 00000000..0bfa465b
--- /dev/null
+++ b/systemd/systemd-fsck@.service.d/cloud-init.conf
@@ -0,0 +1,2 @@
+[Unit]
+After=cloud-init.service