drbd: report net config even for resources without a single volume

Currently it is legal (though unusual) to create and connect a resource,
before adding in all necessary volumes. We should include the network
configuration details, even if we don't have a single volume (yet).

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 862d69e9f1ab2b7b5052fe8738d967b876b632b2..c27b428b9a5b27dd27a20c2aa08dc8ee97fc2c16 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -2731,14 +2731,18 @@ next_tconn:
                        goto out;
 
                if (!mdev) {
-                       /* this is a tconn without a single volume */
+                       /* This is a tconn without a single volume.
+                        * Suprisingly enough, it may have a network
+                        * configuration. */
+                       struct net_conf *nc;
                        dh->minor = -1U;
                        dh->ret_code = NO_ERROR;
                        if (nla_put_drbd_cfg_context(skb, tconn, VOLUME_UNSPECIFIED))
-                               genlmsg_cancel(skb, dh);
-                       else
-                               genlmsg_end(skb, dh);
-                       goto out;
+                               goto cancel;
+                       nc = rcu_dereference(tconn->net_conf);
+                       if (nc && net_conf_to_skb(skb, nc, 1) != 0)
+                               goto cancel;
+                       goto done;
                }
 
                D_ASSERT(mdev->vnr == volume);
@@ -2748,9 +2752,11 @@ next_tconn:
                dh->ret_code = NO_ERROR;
 
                if (nla_put_status_info(skb, mdev, NULL)) {
+cancel:
                        genlmsg_cancel(skb, dh);
                        goto out;
                }
+done:
                genlmsg_end(skb, dh);
         }