service: implement FsckPassNo= option

man/systemd.service.xml

@@ -638,6 +638,33 @@
                                 refers to.</para></listitem>
                         </varlistentry>
 
+                        <varlistentry>
+                                <term><varname>FsckPassNo=</varname></term>
+                                <listitem><para>Set the fsck passno
+                                priority to use to order this service
+                                in relation to other file system
+                                checking services. This option is only
+                                necessary to fix ordering in relation
+                                to fsck jobs automatically created for
+                                all <filename>/etc/fstab</filename>
+                                entries with a value in the fs_passno
+                                column > 0. As such it should only be
+                                used as option for fsck
+                                services. Almost always it is a better
+                                choice to add explicit ordering
+                                directives via
+                                <varname>After=</varname> or
+                                <varname>Before=</varname>,
+                                instead. For more details see
+                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
+                                used, pass an integer value in the
+                                same range as
+                                <filename>/etc/fstab</filename>'s
+                                fs_passno column. See
+                                <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                                for details.</para></listitem>
+                        </varlistentry>
+
                 </variablelist>
         </refsect1>
 

src/load-fragment.c

@@ -1002,6 +1002,32 @@ static int config_parse_sysv_priority(
 }
 #endif
 
+static int config_parse_fsck_passno(
+                const char *filename,
+                unsigned line,
+                const char *section,
+                const char *lvalue,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        int *passno = data;
+        int r, i;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        if ((r = safe_atoi(rvalue, &i)) < 0 || i < 0) {
+                log_error("[%s:%u] Failed to parse fsck pass number, ignoring: %s", filename, line, rvalue);
+                return 0;
+        }
+
+        *passno = (int) i;
+        return 0;
+}
+
 static DEFINE_CONFIG_PARSE_ENUM(config_parse_kill_mode, kill_mode, KillMode, "Failed to parse kill mode");
 
 static int config_parse_kill_signal(
@@ -1781,6 +1807,7 @@ static int load_from_path(Unit *u, const char *path) {
                 { "BusName",                config_parse_string_printf,   &u->service.bus_name,                            "Service" },
                 { "NotifyAccess",           config_parse_notify_access,   &u->service.notify_access,                       "Service" },
                 { "Sockets",                config_parse_service_sockets, &u->service,                                     "Service" },
+                { "FsckPassNo",             config_parse_fsck_passno,     &u->service.fsck_passno,                         "Service" },
                 EXEC_CONTEXT_CONFIG_ITEMS(u->service.exec_context, "Service"),
 
                 { "ListenStream",           config_parse_listen,          &u->socket,                                      "Socket"  },

units/fsck-root.service.in

@@ -15,3 +15,4 @@ Before=local-fs.target shutdown.target remount-rootfs.service quotacheck.service
 Type=oneshot
 RemainAfterExit=no
 ExecStart=@rootlibexecdir@/systemd-fsck
+FsckPassNo=1