+static int synthesize_change(struct udev_device *dev) {
+ char filename[UTIL_PATH_SIZE];
+ int r;
+
+ if (streq_ptr("block", udev_device_get_subsystem(dev)) &&
+ streq_ptr("disk", udev_device_get_devtype(dev)) &&
+ !startswith("dm-", udev_device_get_sysname(dev))) {
+ int fd;
+ struct udev *udev = udev_device_get_udev(dev);
+ _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
+ struct udev_list_entry *item;
+
+ /*
+ * Try to re-read the partition table, this only succeeds if
+ * none of the devices is busy.
+ *
+ * The kernel will send out a change event for the disk, and
+ * "remove/add" for all partitions.
+ */
+ fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
+ if (fd >= 0) {
+ r = ioctl(fd, BLKRRPART, 0);
+ close(fd);
+ if (r >= 0)
+ return 0;
+ }
+
+ /*
+ * Re-reading the partition table did not work, synthesize "change"
+ * events for the disk and all partitions.
+ */
+ log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
+ strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
+ write_string_file(filename, "change");
+
+ e = udev_enumerate_new(udev);
+ if (!e)
+ return -ENOMEM;
+
+ r = udev_enumerate_add_match_parent(e, dev);
+ if (r < 0)
+ return r;
+
+ r = udev_enumerate_add_match_subsystem(e, "block");
+ if (r < 0)
+ return r;
+
+ r = udev_enumerate_scan_devices(e);
+ udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {
+ _cleanup_udev_device_unref_ struct udev_device *d = NULL;
+
+ d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
+ if (!d)
+ continue;
+
+ if (!streq_ptr("partition", udev_device_get_devtype(d)))
+ continue;
+
+ log_debug("device %s closed, synthesising partition '%s' 'change'",
+ udev_device_get_devnode(dev), udev_device_get_devnode(d));
+ strscpyl(filename, sizeof(filename), udev_device_get_syspath(d), "/uevent", NULL);
+ write_string_file(filename, "change");
+ }
+
+ return 0;
+ }
+
+ log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
+ strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
+ write_string_file(filename, "change");
+
+ return 0;
+}
+