a->disk_drain != b->disk_drain;
 }
 
+static void sanitize_disk_conf(struct disk_conf *disk_conf, struct drbd_backing_dev *nbc)
+{
+       if (disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
+               disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
+       if (disk_conf->al_extents > drbd_al_extents_max(nbc))
+               disk_conf->al_extents = drbd_al_extents_max(nbc);
+}
+
 int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 {
        struct drbd_config_context adm_ctx;
        if (!expect(new_disk_conf->resync_rate >= 1))
                new_disk_conf->resync_rate = 1;
 
-       if (new_disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
-               new_disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
-       if (new_disk_conf->al_extents > drbd_al_extents_max(device->ldev))
-               new_disk_conf->al_extents = drbd_al_extents_max(device->ldev);
+       sanitize_disk_conf(new_disk_conf, device->ldev);
 
        if (new_disk_conf->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
                new_disk_conf->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
        if (retcode != NO_ERROR)
                goto fail;
 
-       if (new_disk_conf->al_extents < DRBD_AL_EXTENTS_MIN)
-               new_disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
-       if (new_disk_conf->al_extents > drbd_al_extents_max(nbc))
-               new_disk_conf->al_extents = drbd_al_extents_max(nbc);
+       sanitize_disk_conf(new_disk_conf, nbc);
 
        if (drbd_get_max_capacity(nbc) < new_disk_conf->disk_size) {
                drbd_err(device, "max capacity %llu smaller than disk size %llu\n",