ceph: don't set WRITE_PENDING too early

prepare_write_connect() prepares a connect message, then sets
WRITE_PENDING on the connection.  Then *after* this, it calls
prepare_connect_authorizer(), which updates the content of the
connection buffer already queued for sending.  It's also possible it
will result in prepare_write_connect() returning -EAGAIN despite the
WRITE_PENDING big getting set.

Fix this by preparing the connect authorizer first, setting the
WRITE_PENDING bit only after that is done.

Partially addresses http://tracker.newdream.net/issues/2424

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 47499dc0e41..cf292939dd1 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -697,6 +697,7 @@ static int prepare_write_connect(struct ceph_connection *con)
 {
         unsigned global_seq = get_global_seq(con->msgr, 0);
         int proto;
+        int ret;
 
         switch (con->peer_name.type) {
         case CEPH_ENTITY_TYPE_MON:
@@ -723,11 +724,14 @@ static int prepare_write_connect(struct ceph_connection *con)
         con->out_connect.flags = 0;
 
         ceph_con_out_kvec_add(con, sizeof (con->out_connect), &con->out_connect);
+        ret = prepare_connect_authorizer(con);
+        if (ret)
+                return ret;
 
         con->out_more = 0;
         set_bit(WRITE_PENDING, &con->state);
 
-        return prepare_connect_authorizer(con);
+        return 0;
 }
 
 /*