device : reload when udev generates a "changed" event

2 files changed, 27 insertions, 1 deletions

diff --git a/man/systemd.device.xml b/man/systemd.device.xml
index effed098dd..d156095526 100644
--- a/man/systemd.device.xml
+++ b/man/systemd.device.xml
@@ -83,6 +83,12 @@
     the escaping logic used to convert a file system path to a unit
     name see
     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+
+    <para>Device units will be reloaded by systemd whenever the
+    corresponding device generates a <literal>changed</literal> event.
+    Other units can use <varname>ReloadPropagatedFrom=</varname> to react
+    to that event</para>
+
   </refsect1>
 
   <refsect1>
diff --git a/src/core/device.c b/src/core/device.c
index 87186f135b..5366ba050f 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -766,7 +766,27 @@ static int device_dispatch_io(sd_event_source *source, int fd, uint32_t revents,
                 return 0;
         }
 
-        if (streq(action, "remove"))  {
+        if (streq(action, "change"))  {
+                _cleanup_free_ char *e = NULL;
+                Unit *u;
+
+                r = unit_name_from_path(sysfs, ".device", &e);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to generate unit name from device path: %m");
+
+                u = manager_get_unit(m, e);
+                if (!u) {
+                        log_error("Failed to get unit from sysfs name.");
+                        return 0;
+                }
+
+                r = manager_add_job(m, JOB_RELOAD, u, JOB_REPLACE, NULL, NULL);
+                if (r < 0) {
+                        log_error_errno(r, "Failed to add job to manager : %m");
+                        return 0;
+                }
+
+        } else if (streq(action, "remove"))  {
                 r = swap_process_device_remove(m, dev);
                 if (r < 0)
                         log_error_errno(r, "Failed to process swap device remove event: %m");