drbd: Allow a Diskless Secondary volume to be removed

Even if the connection is still established.
We should be able to reduce a volume from a replication group,
without taking the whole group offline.

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 244085ac12cc796b705960fc6a65e169689a3853..9b0312f2d2f87d4e5b54fa6902d3471b8be0d418 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -220,6 +220,8 @@ static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info,
                drbd_msg_put_info("over-determined configuration context mismatch");
                return ERR_INVALID_REQUEST;
        }
+       if (adm_ctx.mdev && !adm_ctx.tconn)
+               adm_ctx.tconn = adm_ctx.mdev->tconn;
        return NO_ERROR;
 
 fail:
@@ -2643,10 +2645,15 @@ int drbd_adm_delete_minor(struct sk_buff *skb, struct genl_info *info)
 
        mdev = adm_ctx.mdev;
        if (mdev->state.disk == D_DISKLESS &&
-           mdev->state.conn == C_STANDALONE &&
+           /* no need to be mdev->state.conn == C_STANDALONE &&
+            * we may want to delete a minor from a live replication group.
+            */
            mdev->state.role == R_SECONDARY) {
                drbd_delete_device(mdev_to_minor(mdev));
                retcode = NO_ERROR;
+               /* if this was the last volume of this connection,
+                * this will terminate all threads */
+               conn_reconfig_done(adm_ctx.tconn);
        } else
                retcode = ERR_MINOR_CONFIGURED;
 out: