drbd: Runtime changeable wire protocol
The wire protocol is no longer a property that is negotiated
between the two peers. It is now expressed with two bits
(DP_SEND_WRITE_ACK and DP_SEND_RECEIVE_ACK) in each data
packet. Therefore the primary node is free to change the
wire protocol at any time without disconnect/reconnect.
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_main.c b/drivers/block/drbd/drbd_main.c
index f298f9c..d3e3c11 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1681,6 +1681,12 @@
if (mdev->state.conn >= C_SYNC_SOURCE &&
mdev->state.conn <= C_PAUSED_SYNC_T)
dp_flags |= DP_MAY_SET_IN_SYNC;
+ if (mdev->tconn->agreed_pro_version >= 100) {
+ if (req->rq_state & RQ_EXP_RECEIVE_ACK)
+ dp_flags |= DP_SEND_RECEIVE_ACK;
+ if (req->rq_state & RQ_EXP_WRITE_ACK)
+ dp_flags |= DP_SEND_WRITE_ACK;
+ }
p->dp_flags = cpu_to_be32(dp_flags);
if (dgs)
drbd_csum_bio(mdev, mdev->tconn->integrity_w_tfm, req->master_bio, p + 1);
@@ -1697,7 +1703,7 @@
* out ok after sending on this side, but does not fit on the
* receiving side, we sure have detected corruption elsewhere.
*/
- if (mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A || dgs)
+ if (!(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK)) || dgs)
err = _drbd_send_bio(mdev, req->master_bio);
else
err = _drbd_send_zc_bio(mdev, req->master_bio);
