drbd: ignore volume number for drbd barrier packet exchange

Transfer log epochs, and therefore P_BARRIER packets,
are per resource, not per volume.
We must not associate them with "some random volume".

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

3 files changed, 31 insertions, 36 deletions

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index ab9926e915cb..85769085485d 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -584,7 +584,7 @@ struct drbd_tl_epoch {
 };
 
 struct drbd_epoch {
-        struct drbd_conf *mdev;
+        struct drbd_tconn *tconn;
         struct list_head list;
         unsigned int barrier_nr;
         atomic_t epoch_size; /* increased on every request added. */
@@ -1060,7 +1060,7 @@ extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_f
 extern int drbd_send_state(struct drbd_conf *mdev, union drbd_state s);
 extern int drbd_send_current_state(struct drbd_conf *mdev);
 extern int drbd_send_sync_param(struct drbd_conf *mdev);
-extern void drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr,
+extern void drbd_send_b_ack(struct drbd_tconn *tconn, u32 barrier_nr,
                             u32 set_size);
 extern int drbd_send_ack(struct drbd_conf *, enum drbd_packet,
                          struct drbd_peer_request *);
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 5529d392e5d3..f8438d426d06 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1463,21 +1463,21 @@ int drbd_send_bitmap(struct drbd_conf *mdev)
         return err;
 }
 
-void drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
+void drbd_send_b_ack(struct drbd_tconn *tconn, u32 barrier_nr, u32 set_size)
 {
         struct drbd_socket *sock;
         struct p_barrier_ack *p;
 
-        if (mdev->state.conn < C_CONNECTED)
+        if (tconn->cstate < C_WF_REPORT_PARAMS)
                 return;
 
-        sock = &mdev->tconn->meta;
-        p = drbd_prepare_command(mdev, sock);
+        sock = &tconn->meta;
+        p = conn_prepare_command(tconn, sock);
         if (!p)
                 return;
         p->barrier = barrier_nr;
         p->set_size = cpu_to_be32(set_size);
-        drbd_send_command(mdev, sock, P_BARRIER_ACK, sizeof(*p), NULL, 0);
+        conn_send_command(tconn, sock, P_BARRIER_ACK, sizeof(*p), NULL, 0);
 }
 
 /**
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index b159ad15abe5..786a75510798 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -1169,11 +1169,15 @@ static enum finish_epoch drbd_may_finish_epoch(struct drbd_tconn *tconn,
                     (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags) || ev & EV_CLEANUP)) {
                         if (!(ev & EV_CLEANUP)) {
                                 spin_unlock(&tconn->epoch_lock);
-                                drbd_send_b_ack(epoch->mdev, epoch->barrier_nr, epoch_size);
+                                drbd_send_b_ack(epoch->tconn, epoch->barrier_nr, epoch_size);
                                 spin_lock(&tconn->epoch_lock);
                         }
+#if 0
+                        /* FIXME: dec unacked on connection, once we have
+                         * something to count pending connection packets in. */
                         if (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags))
-                                dec_unacked(epoch->mdev);
+                                dec_unacked(epoch->tconn);
+#endif
 
                         if (tconn->current_epoch != epoch) {
                                 next_epoch = list_entry(epoch->list.next, struct drbd_epoch, list);
@@ -1369,19 +1373,15 @@ void conn_wait_active_ee_empty(struct drbd_tconn *tconn)
 
 static int receive_Barrier(struct drbd_tconn *tconn, struct packet_info *pi)
 {
-        struct drbd_conf *mdev;
         int rv;
         struct p_barrier *p = pi->data;
         struct drbd_epoch *epoch;
 
-        mdev = vnr_to_mdev(tconn, pi->vnr);
-        if (!mdev)
-                return -EIO;
-
-        inc_unacked(mdev);
-
+        /* FIXME these are unacked on connection,
+         * not a specific (peer)device.
+         */
         tconn->current_epoch->barrier_nr = p->barrier;
-        tconn->current_epoch->mdev = mdev;
+        tconn->current_epoch->tconn = tconn;
         rv = drbd_may_finish_epoch(tconn, tconn->current_epoch, EV_GOT_BARRIER_NR);
 
         /* P_BARRIER_ACK may imply that the corresponding extent is dropped from
@@ -1400,7 +1400,7 @@ static int receive_Barrier(struct drbd_tconn *tconn, struct packet_info *pi)
                 if (epoch)
                         break;
                 else
-                        dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
+                        conn_warn(tconn, "Allocation of an epoch failed, slowing down\n");
                         /* Fall through */
 
         case WO_bdev_flush:
@@ -1414,15 +1414,9 @@ static int receive_Barrier(struct drbd_tconn *tconn, struct packet_info *pi)
                                 break;
                 }
 
-                epoch = tconn->current_epoch;
-                wait_event(mdev->ee_wait, atomic_read(&epoch->epoch_size) == 0);
-
-                D_ASSERT(atomic_read(&epoch->active) == 0);
-                D_ASSERT(epoch->flags == 0);
-
                 return 0;
         default:
-                dev_err(DEV, "Strangeness in tconn->write_ordering %d\n", tconn->write_ordering);
+                conn_err(tconn, "Strangeness in tconn->write_ordering %d\n", tconn->write_ordering);
                 return -EIO;
         }
 
@@ -5049,21 +5043,22 @@ static int got_NegRSDReply(struct drbd_tconn *tconn, struct packet_info *pi)
 
 static int got_BarrierAck(struct drbd_tconn *tconn, struct packet_info *pi)
 {
-        struct drbd_conf *mdev;
         struct p_barrier_ack *p = pi->data;
+        struct drbd_conf *mdev;
+        int vnr;
 
-        mdev = vnr_to_mdev(tconn, pi->vnr);
-        if (!mdev)
-                return -EIO;
-
-        tl_release(mdev->tconn, p->barrier, be32_to_cpu(p->set_size));
+        tl_release(tconn, p->barrier, be32_to_cpu(p->set_size));
 
-        if (mdev->state.conn == C_AHEAD &&
-            atomic_read(&mdev->ap_in_flight) == 0 &&
-            !test_and_set_bit(AHEAD_TO_SYNC_SOURCE, &mdev->flags)) {
-                mdev->start_resync_timer.expires = jiffies + HZ;
-                add_timer(&mdev->start_resync_timer);
+        rcu_read_lock();
+        idr_for_each_entry(&tconn->volumes, mdev, vnr) {
+                if (mdev->state.conn == C_AHEAD &&
+                    atomic_read(&mdev->ap_in_flight) == 0 &&
+                    !test_and_set_bit(AHEAD_TO_SYNC_SOURCE, &mdev->flags)) {
+                        mdev->start_resync_timer.expires = jiffies + HZ;
+                        add_timer(&mdev->start_resync_timer);
+                }
         }
+        rcu_read_unlock();
 
         return 0;
 }