unsigned int in_use;
        int i;
 
-       if (!expect(dc->al_extents >= DRBD_AL_EXTENTS_MIN))
-               dc->al_extents = DRBD_AL_EXTENTS_MIN;
-
        if (mdev->act_log &&
            mdev->act_log->nr_elements == dc->al_extents)
                return 0;
        return 0 != (flags & DRBD_GENL_F_SET_DEFAULTS);
 }
 
+static void enforce_disk_conf_limits(struct disk_conf *dc)
+{
+       if (dc->al_extents < DRBD_AL_EXTENTS_MIN)
+               dc->al_extents = DRBD_AL_EXTENTS_MIN;
+       if (dc->al_extents > DRBD_AL_EXTENTS_MAX)
+               dc->al_extents = DRBD_AL_EXTENTS_MAX;
+
+       if (dc->c_plan_ahead > DRBD_C_PLAN_AHEAD_MAX)
+               dc->c_plan_ahead = DRBD_C_PLAN_AHEAD_MAX;
+}
+
 int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 {
        enum drbd_ret_code retcode;
        if (!expect(new_disk_conf->resync_rate >= 1))
                new_disk_conf->resync_rate = 1;
 
-       /* clip to allowed range */
-       if (!expect(new_disk_conf->al_extents >= DRBD_AL_EXTENTS_MIN))
-               new_disk_conf->al_extents = DRBD_AL_EXTENTS_MIN;
-       if (!expect(new_disk_conf->al_extents <= DRBD_AL_EXTENTS_MAX))
-               new_disk_conf->al_extents = DRBD_AL_EXTENTS_MAX;
+       enforce_disk_conf_limits(new_disk_conf);
 
        fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
        if (fifo_size != mdev->rs_plan_s->size) {
                goto fail;
        }
 
+       enforce_disk_conf_limits(new_disk_conf);
+
        new_plan = fifo_alloc((new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ);
        if (!new_plan) {
                retcode = ERR_NOMEM;
        else
                clear_bit(MD_NO_FUA, &mdev->flags);
 
-       /* FIXME Missing stuff: clip al range */
-
        /* Point of no return reached.
         * Devices and memory are no longer released by error cleanup below.
         * now mdev takes over responsibility, and the state engine should