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_int.h b/drivers/block/drbd/drbd_int.h
index 2119d9b..c57cedb 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -327,6 +327,8 @@
#define DP_FUA 16 /* equals REQ_FUA */
#define DP_FLUSH 32 /* equals REQ_FLUSH */
#define DP_DISCARD 64 /* equals REQ_DISCARD */
+#define DP_SEND_RECEIVE_ACK 128 /* This is a proto B write request */
+#define DP_SEND_WRITE_ACK 256 /* This is a proto C write request */
struct p_data {
u64 sector; /* 64 bits sector number */
@@ -656,6 +658,9 @@
/* Conflicting local requests need to be restarted after this request */
__EE_RESTART_REQUESTS,
+
+ /* The peer wants a write ACK for this (wire proto C) */
+ __EE_SEND_WRITE_ACK,
};
#define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO)
#define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC)
@@ -663,6 +668,7 @@
#define EE_WAS_ERROR (1<<__EE_WAS_ERROR)
#define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST)
#define EE_RESTART_REQUESTS (1<<__EE_RESTART_REQUESTS)
+#define EE_SEND_WRITE_ACK (1<<__EE_SEND_WRITE_ACK)
/* flag bits per mdev */
enum {
