drbd: Delayed creation of current-UUID

When a fencing policy of "resource-and-stonith" is configured,
and DRBD looses connection to it's peer, we can delay the
creation of a new current-UUID until IO gets thawed.

That allows one to deploy fence-peer handlers that actually
commit suicide on the machine they get started.

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

1 files changed, 21 insertions, 6 deletions

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 40baddd94a5b..440b1d5dcfe2 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1252,12 +1252,23 @@ static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
         }
 
         if (fp == FP_STONITH && ns.susp) {
-                /* case1: The outdate peer handler is successful:
-                 * case2: The connection was established again: */
-                if ((os.pdsk > D_OUTDATED  && ns.pdsk <= D_OUTDATED) ||
-                    (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
+                /* case1: The outdate peer handler is successful: */
+                if (os.pdsk > D_OUTDATED  && ns.pdsk <= D_OUTDATED) {
                         tl_clear(mdev);
+                        if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
+                                drbd_uuid_new_current(mdev);
+                                clear_bit(NEW_CUR_UUID, &mdev->flags);
+                                drbd_md_sync(mdev);
+                        }
+                        spin_lock_irq(&mdev->req_lock);
+                        _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
+                        spin_unlock_irq(&mdev->req_lock);
+                }
+                /* case2: The connection was established again: */
+                if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) {
+                        clear_bit(NEW_CUR_UUID, &mdev->flags);
                         spin_lock_irq(&mdev->req_lock);
+                        _tl_restart(mdev, resend);
                         _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
                         spin_unlock_irq(&mdev->req_lock);
                 }
@@ -1280,8 +1291,12 @@ static void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
                 if (get_ldev(mdev)) {
                         if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
                             mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
-                                drbd_uuid_new_current(mdev);
-                                drbd_send_uuids(mdev);
+                                if (mdev->state.susp) {
+                                        set_bit(NEW_CUR_UUID, &mdev->flags);
+                                } else {
+                                        drbd_uuid_new_current(mdev);
+                                        drbd_send_uuids(mdev);
+                                }
                         }
                         put_ldev(mdev);
                 }