libceph: implement RECONNECT_SEQ feature
This is an old protocol extension that allows the client and server to
avoid resending old messages after a reconnect (following a socket error).
Instead, the exchange their sequence numbers during the handshake. This
avoids sending a bunch of useless data over the socket.
It has been supported in the server code since v0.22 (Sep 2010).
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
diff --git a/include/linux/ceph/msgr.h b/include/linux/ceph/msgr.h
index 680d3d6..3d94a73 100644
--- a/include/linux/ceph/msgr.h
+++ b/include/linux/ceph/msgr.h
@@ -87,6 +87,7 @@
#define CEPH_MSGR_TAG_BADPROTOVER 10 /* bad protocol version */
#define CEPH_MSGR_TAG_BADAUTHORIZER 11 /* bad authorizer */
#define CEPH_MSGR_TAG_FEATURES 12 /* insufficient features */
+#define CEPH_MSGR_TAG_SEQ 13 /* 64-bit int follows with seen seq number */
/*