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_req.h b/drivers/block/drbd/drbd_req.h
index 0dabfa9..5135c95 100644
--- a/drivers/block/drbd/drbd_req.h
+++ b/drivers/block/drbd/drbd_req.h
@@ -198,6 +198,12 @@
/* The peer has sent a retry ACK */
__RQ_POSTPONED,
+
+ /* We expect a receive ACK (wire proto B) */
+ __RQ_EXP_RECEIVE_ACK,
+
+ /* We expect a write ACK (wite proto C) */
+ __RQ_EXP_WRITE_ACK,
};
#define RQ_LOCAL_PENDING (1UL << __RQ_LOCAL_PENDING)
@@ -219,6 +225,8 @@
#define RQ_WRITE (1UL << __RQ_WRITE)
#define RQ_IN_ACT_LOG (1UL << __RQ_IN_ACT_LOG)
#define RQ_POSTPONED (1UL << __RQ_POSTPONED)
+#define RQ_EXP_RECEIVE_ACK (1UL << __RQ_EXP_RECEIVE_ACK)
+#define RQ_EXP_WRITE_ACK (1UL << __RQ_EXP_WRITE_ACK)
/* For waking up the frozen transfer log mod_req() has to return if the request
should be counted in the epoch object*/