diff --git a/examples/client.c b/examples/client.c
index 6fc2f9e7..4e951db4 100644
--- a/examples/client.c
+++ b/examples/client.c
@@ -318,7 +318,8 @@ static int on_stream_close_callback(nghttp2_session *session,
   req = nghttp2_session_get_stream_user_data(session, stream_id);
   if(req) {
     int rv;
-    rv = nghttp2_submit_goaway(session, NGHTTP2_NO_ERROR, NULL, 0);
+    rv = nghttp2_submit_goaway(session, NGHTTP2_FLAG_NONE, NGHTTP2_NO_ERROR,
+                               NULL, 0);
     if(rv != 0) {
       diec("nghttp2_submit_goaway", rv);
     }
@@ -350,7 +351,8 @@ static int on_data_chunk_recv_callback(nghttp2_session *session, uint8_t flags,
         int rv;
         rv = nghttp2_gzip_inflate(req->inflater, out, &outlen, data, &tlen);
         if(rv == -1) {
-          nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_INTERNAL_ERROR);
+          nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, stream_id,
+                                    NGHTTP2_INTERNAL_ERROR);
           break;
         }
         fwrite(out, 1, outlen, stdout);
diff --git a/lib/includes/nghttp2/nghttp2.h b/lib/includes/nghttp2/nghttp2.h
index ead216c6..3808dbfb 100644
--- a/lib/includes/nghttp2/nghttp2.h
+++ b/lib/includes/nghttp2/nghttp2.h
@@ -1831,6 +1831,9 @@ int nghttp2_submit_data(nghttp2_session *session, uint8_t flags,
  * Submits PRIORITY frame to change the priority of stream |stream_id|
  * to the priority value |pri|.
  *
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
+ *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes:
  *
@@ -1841,8 +1844,8 @@ int nghttp2_submit_data(nghttp2_session *session, uint8_t flags,
  * :enum:`NGHTTP2_ERR_STREAM_CLOSED`
  *     The stream is already closed or does not exist.
  */
-int nghttp2_submit_priority(nghttp2_session *session, int32_t stream_id,
-                            int32_t pri);
+int nghttp2_submit_priority(nghttp2_session *session, uint8_t flags,
+                            int32_t stream_id, int32_t pri);
 
 /**
  * @function
@@ -1850,13 +1853,17 @@ int nghttp2_submit_priority(nghttp2_session *session, int32_t stream_id,
  * Submits RST_STREAM frame to cancel/reject the stream |stream_id|
  * with the error code |error_code|.
  *
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
+ *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes:
  *
  * :enum:`NGHTTP2_ERR_NOMEM`
  *     Out of memory.
  */
-int nghttp2_submit_rst_stream(nghttp2_session *session, int32_t stream_id,
+int nghttp2_submit_rst_stream(nghttp2_session *session, uint8_t flags,
+                              int32_t stream_id,
                               nghttp2_error_code error_code);
 
 /**
@@ -1866,6 +1873,9 @@ int nghttp2_submit_rst_stream(nghttp2_session *session, int32_t stream_id,
  * pointer to the array of :type:`nghttp2_settings_entry`. The |niv|
  * indicates the number of :type:`nghttp2_settings_entry`.
  *
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
+ *
  * This function does not take ownership of the |iv|. This function
  * copies all the elements in the |iv|.
  *
@@ -1882,7 +1892,7 @@ int nghttp2_submit_rst_stream(nghttp2_session *session, int32_t stream_id,
  * :enum:`NGHTTP2_ERR_NOMEM`
  *     Out of memory.
  */
-int nghttp2_submit_settings(nghttp2_session *session,
+int nghttp2_submit_settings(nghttp2_session *session, uint8_t flags,
                             const nghttp2_settings_entry *iv, size_t niv);
 
 
@@ -1934,6 +1944,9 @@ int nghttp2_submit_push_promise(nghttp2_session *session, uint8_t flags,
  * received PING frame. The library automatically submits PING frame
  * in this case.
  *
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
+ *
  * If the |opaque_data| is non ``NULL``, then it should point to the 8
  * bytes array of memory to specify opaque data to send with PING
  * frame. If the |opaque_data| is ``NULL``, zero-cleared 8 bytes will
@@ -1945,13 +1958,17 @@ int nghttp2_submit_push_promise(nghttp2_session *session, uint8_t flags,
  * :enum:`NGHTTP2_ERR_NOMEM`
  *     Out of memory.
  */
-int nghttp2_submit_ping(nghttp2_session *session, uint8_t *opaque_data);
+int nghttp2_submit_ping(nghttp2_session *session, uint8_t flags,
+                        uint8_t *opaque_data);
 
 /**
  * @function
  *
  * Submits GOAWAY frame with the error code |error_code|.
  *
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
+ *
  * If the |opaque_data| is not ``NULL`` and |opaque_data_len| is not
  * zero, those data will be sent as additional debug data.  The
  * library makes a copy of the memory region pointed by |opaque_data|
@@ -1965,7 +1982,7 @@ int nghttp2_submit_ping(nghttp2_session *session, uint8_t *opaque_data);
  * :enum:`NGHTTP2_ERR_NOMEM`
  *     Out of memory.
  */
-int nghttp2_submit_goaway(nghttp2_session *session,
+int nghttp2_submit_goaway(nghttp2_session *session, uint8_t flags,
                           nghttp2_error_code error_code,
                           uint8_t *opaque_data, size_t opaque_data_len);
 
@@ -1974,7 +1991,8 @@ int nghttp2_submit_goaway(nghttp2_session *session,
  *
  * Submits WINDOW_UPDATE frame.
  *
- * The |flags| is currently ignored.
+ * The |flags| is currently ignored and should be
+ * :enum:`NGHTTP2_FLAG_NONE`.
  *
  * If the |window_size_increment| is positive, the WINDOW_UPDATE with
  * that value as window_size_increment is queued. If the
diff --git a/lib/nghttp2_session.c b/lib/nghttp2_session.c
index 048b0a2a..5ccc3073 100644
--- a/lib/nghttp2_session.c
+++ b/lib/nghttp2_session.c
@@ -90,7 +90,8 @@ int nghttp2_session_fail_session(nghttp2_session *session,
   if(session->goaway_flags & NGHTTP2_GOAWAY_SEND) {
     return 0;
   }
-  return nghttp2_submit_goaway(session, error_code, NULL, 0);
+  return nghttp2_submit_goaway(session, NGHTTP2_FLAG_NONE, error_code,
+                               NULL, 0);
 }
 
 int nghttp2_session_is_my_stream_id(nghttp2_session *session,
@@ -3476,7 +3477,7 @@ int nghttp2_session_upgrade(nghttp2_session *session,
     frame.settings.niv = niv;
     rv = nghttp2_session_on_settings_received(session, &frame);
   } else {
-    rv = nghttp2_submit_settings(session, iv, niv);
+    rv = nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, niv);
   }
   free(iv);
   if(rv != 0) {
diff --git a/lib/nghttp2_submit.c b/lib/nghttp2_submit.c
index ac248e2b..d47ce738 100644
--- a/lib/nghttp2_submit.c
+++ b/lib/nghttp2_submit.c
@@ -154,13 +154,14 @@ int nghttp2_submit_headers(nghttp2_session *session, uint8_t flags,
 }
 
 
-int nghttp2_submit_ping(nghttp2_session *session, uint8_t *opaque_data)
+int nghttp2_submit_ping(nghttp2_session *session, uint8_t flags,
+                        uint8_t *opaque_data)
 {
   return nghttp2_session_add_ping(session, NGHTTP2_FLAG_NONE, opaque_data);
 }
 
-int nghttp2_submit_priority(nghttp2_session *session, int32_t stream_id,
-                            int32_t pri)
+int nghttp2_submit_priority(nghttp2_session *session, uint8_t flags,
+                            int32_t stream_id, int32_t pri)
 {
   int r;
   nghttp2_frame *frame;
@@ -190,13 +191,14 @@ int nghttp2_submit_priority(nghttp2_session *session, int32_t stream_id,
   return 0;
 }
 
-int nghttp2_submit_rst_stream(nghttp2_session *session, int32_t stream_id,
+int nghttp2_submit_rst_stream(nghttp2_session *session, uint8_t flags,
+                              int32_t stream_id,
                               nghttp2_error_code error_code)
 {
   return nghttp2_session_add_rst_stream(session, stream_id, error_code);
 }
 
-int nghttp2_submit_goaway(nghttp2_session *session,
+int nghttp2_submit_goaway(nghttp2_session *session, uint8_t flags,
                           nghttp2_error_code error_code,
                           uint8_t *opaque_data, size_t opaque_data_len)
 {
@@ -204,7 +206,7 @@ int nghttp2_submit_goaway(nghttp2_session *session,
                                     error_code, opaque_data, opaque_data_len);
 }
 
-int nghttp2_submit_settings(nghttp2_session *session,
+int nghttp2_submit_settings(nghttp2_session *session, uint8_t flags,
                             const nghttp2_settings_entry *iv, size_t niv)
 {
   nghttp2_frame *frame;
diff --git a/src/HttpServer.cc b/src/HttpServer.cc
index 8db78a4b..39652b3f 100644
--- a/src/HttpServer.cc
+++ b/src/HttpServer.cc
@@ -358,7 +358,7 @@ int Http2Handler::on_connect()
     entry[niv].value = 1;
     ++niv;
   }
-  r = nghttp2_submit_settings(session_, entry, niv);
+  r = nghttp2_submit_settings(session_, NGHTTP2_FLAG_NONE, entry, niv);
   if(r != 0) {
     return r;
   }
@@ -701,14 +701,15 @@ int hd_on_frame_recv_callback
       int32_t stream_id = frame->hd.stream_id;
       if(!http2::check_http2_headers(frame->headers.nva,
                                      frame->headers.nvlen)) {
-        nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_PROTOCOL_ERROR);
+        nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, stream_id,
+                                  NGHTTP2_PROTOCOL_ERROR);
         return 0;
       }
       for(size_t i = 0; REQUIRED_HEADERS[i]; ++i) {
         if(!http2::get_unique_header(frame->headers.nva,
                                      frame->headers.nvlen,
                                      REQUIRED_HEADERS[i])) {
-          nghttp2_submit_rst_stream(session, stream_id,
+          nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, stream_id,
                                     NGHTTP2_PROTOCOL_ERROR);
           return 0;
         }
diff --git a/src/nghttp.cc b/src/nghttp.cc
index 938c7ea1..91d99a2d 100644
--- a/src/nghttp.cc
+++ b/src/nghttp.cc
@@ -685,7 +685,7 @@ struct HttpClient {
     if(!need_upgrade()) {
       nghttp2_settings_entry iv[16];
       auto niv = populate_settings(iv);
-      rv = nghttp2_submit_settings(session, iv, niv);
+      rv = nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, niv);
       if(rv != 0) {
         return -1;
       }
@@ -1012,7 +1012,8 @@ int on_data_chunk_recv_callback
         size_t tlen = len;
         int rv = nghttp2_gzip_inflate(req->inflater, out, &outlen, data, &tlen);
         if(rv != 0) {
-          nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_INTERNAL_ERROR);
+          nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, stream_id,
+                                    NGHTTP2_INTERNAL_ERROR);
           break;
         }
         if(!config.null_out) {
@@ -1140,7 +1141,8 @@ int on_stream_close_callback
     (*itr).second->record_complete_time();
     ++client->complete;
     if(client->all_requests_processed()) {
-      nghttp2_submit_goaway(session, NGHTTP2_NO_ERROR, nullptr, 0);
+      nghttp2_submit_goaway(session, NGHTTP2_FLAG_NONE, NGHTTP2_NO_ERROR,
+                            nullptr, 0);
     }
   }
   return 0;
diff --git a/src/shrpx_http2_upstream.cc b/src/shrpx_http2_upstream.cc
index 7be268a3..a9b3af20 100644
--- a/src/shrpx_http2_upstream.cc
+++ b/src/shrpx_http2_upstream.cc
@@ -443,8 +443,9 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
   entry[1].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
   entry[1].value = initial_window_size_;
 
-  rv = nghttp2_submit_settings
-    (session_, entry, sizeof(entry)/sizeof(nghttp2_settings_entry));
+  rv = nghttp2_submit_settings(session_, NGHTTP2_FLAG_NONE,
+                               entry,
+                               sizeof(entry)/sizeof(nghttp2_settings_entry));
   assert(rv == 0);
   // Set large connection-level window size to effectively disable
   // connection-level flow control.
@@ -715,8 +716,8 @@ int Http2Upstream::rst_stream(Downstream *downstream,
                      << error_code;
   }
   int rv;
-  rv = nghttp2_submit_rst_stream(session_, downstream->get_stream_id(),
-                                 error_code);
+  rv = nghttp2_submit_rst_stream(session_, NGHTTP2_FLAG_NONE,
+                                 downstream->get_stream_id(), error_code);
   if(rv < NGHTTP2_ERR_FATAL) {
     ULOG(FATAL, this) << "nghttp2_submit_rst_stream() failed: "
                       << nghttp2_strerror(rv);
diff --git a/src/shrpx_spdy_downstream_connection.cc b/src/shrpx_spdy_downstream_connection.cc
index bdc01c64..1c37d089 100644
--- a/src/shrpx_spdy_downstream_connection.cc
+++ b/src/shrpx_spdy_downstream_connection.cc
@@ -145,8 +145,7 @@ int SpdyDownstreamConnection::submit_rst_stream(Downstream *downstream)
                           << downstream << ", stream_id="
                           << downstream->get_downstream_stream_id();
       }
-      rv = spdy_->submit_rst_stream(this,
-                                    downstream->get_downstream_stream_id(),
+      rv = spdy_->submit_rst_stream(downstream->get_downstream_stream_id(),
                                     NGHTTP2_INTERNAL_ERROR);
     }
   }
diff --git a/src/shrpx_spdy_session.cc b/src/shrpx_spdy_session.cc
index 7a58385f..40848a1f 100644
--- a/src/shrpx_spdy_session.cc
+++ b/src/shrpx_spdy_session.cc
@@ -577,8 +577,7 @@ int SpdySession::submit_request(SpdyDownstreamConnection *dconn,
   return 0;
 }
 
-int SpdySession::submit_rst_stream(SpdyDownstreamConnection *dconn,
-                                   int32_t stream_id,
+int SpdySession::submit_rst_stream(int32_t stream_id,
                                    nghttp2_error_code error_code)
 {
   assert(state_ == CONNECTED);
@@ -588,7 +587,8 @@ int SpdySession::submit_rst_stream(SpdyDownstreamConnection *dconn,
                       << " with error_code="
                       << error_code;
   }
-  int rv = nghttp2_submit_rst_stream(session_, stream_id, error_code);
+  int rv = nghttp2_submit_rst_stream(session_, NGHTTP2_FLAG_NONE,
+                                     stream_id, error_code);
   if(rv != 0) {
     SSLOG(FATAL, this) << "nghttp2_submit_rst_stream() failed: "
                        << nghttp2_strerror(rv);
@@ -750,15 +750,13 @@ int on_frame_recv_callback
     auto sd = reinterpret_cast<StreamData*>
       (nghttp2_session_get_stream_user_data(session, frame->hd.stream_id));
     if(!sd || !sd->dconn) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_INTERNAL_ERROR);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_INTERNAL_ERROR);
       break;
     }
     auto downstream = sd->dconn->get_downstream();
     if(!downstream ||
        downstream->get_downstream_stream_id() != frame->hd.stream_id) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_INTERNAL_ERROR);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_INTERNAL_ERROR);
       break;
     }
     auto nva = frame->headers.nva;
@@ -766,8 +764,7 @@ int on_frame_recv_callback
 
     // Assuming that nva is sorted by name.
     if(!http2::check_http2_headers(nva, nvlen)) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_PROTOCOL_ERROR);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_PROTOCOL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
       call_downstream_readcb(spdy, downstream);
       return 0;
@@ -782,8 +779,7 @@ int on_frame_recv_callback
 
     auto status = http2::get_unique_header(nva, nvlen, ":status");
     if(!status || http2::value_lws(status)) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_PROTOCOL_ERROR);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_PROTOCOL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
       call_downstream_readcb(spdy, downstream);
       return 0;
@@ -855,8 +851,7 @@ int on_frame_recv_callback
     }
     rv = upstream->on_downstream_header_complete(downstream);
     if(rv != 0) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_PROTOCOL_ERROR);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_PROTOCOL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
     }
     call_downstream_readcb(spdy, downstream);
@@ -899,8 +894,7 @@ int on_frame_recv_callback
                         << frame->hd.stream_id;
     }
     // We just respond with RST_STREAM.
-    nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                              NGHTTP2_REFUSED_STREAM);
+    spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_REFUSED_STREAM);
     break;
   default:
     break;
@@ -920,12 +914,12 @@ int on_data_chunk_recv_callback(nghttp2_session *session,
   auto sd = reinterpret_cast<StreamData*>
     (nghttp2_session_get_stream_user_data(session, stream_id));
   if(!sd || !sd->dconn) {
-    nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_INTERNAL_ERROR);
+    spdy->submit_rst_stream(stream_id, NGHTTP2_INTERNAL_ERROR);
     return 0;
   }
   auto downstream = sd->dconn->get_downstream();
   if(!downstream || downstream->get_downstream_stream_id() != stream_id) {
-    nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_INTERNAL_ERROR);
+    spdy->submit_rst_stream(stream_id, NGHTTP2_INTERNAL_ERROR);
     return 0;
   }
 
@@ -940,8 +934,7 @@ int on_data_chunk_recv_callback(nghttp2_session *session,
                           << ", initial_window_size="
                           << spdy->get_initial_window_size();
       }
-      nghttp2_submit_rst_stream(session, stream_id,
-                                NGHTTP2_FLOW_CONTROL_ERROR);
+      spdy->submit_rst_stream(stream_id, NGHTTP2_FLOW_CONTROL_ERROR);
       downstream->set_response_state(Downstream::MSG_RESET);
       call_downstream_readcb(spdy, downstream);
       return 0;
@@ -951,7 +944,7 @@ int on_data_chunk_recv_callback(nghttp2_session *session,
   auto upstream = downstream->get_upstream();
   rv = upstream->on_downstream_body(downstream, data, len);
   if(rv != 0) {
-    nghttp2_submit_rst_stream(session, stream_id, NGHTTP2_INTERNAL_ERROR);
+    spdy->submit_rst_stream(stream_id, NGHTTP2_INTERNAL_ERROR);
     downstream->set_response_state(Downstream::MSG_RESET);
   }
   call_downstream_readcb(spdy, downstream);
@@ -964,20 +957,20 @@ int before_frame_send_callback(nghttp2_session *session,
                                const nghttp2_frame *frame,
                                void *user_data)
 {
+  auto spdy = reinterpret_cast<SpdySession*>(user_data);
   if(frame->hd.type == NGHTTP2_HEADERS &&
      frame->headers.cat == NGHTTP2_HCAT_REQUEST) {
     auto sd = reinterpret_cast<StreamData*>
       (nghttp2_session_get_stream_user_data(session, frame->hd.stream_id));
     if(!sd || !sd->dconn) {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id,
-                                NGHTTP2_CANCEL);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_CANCEL);
       return 0;
     }
     auto downstream = sd->dconn->get_downstream();
     if(downstream) {
       downstream->set_downstream_stream_id(frame->hd.stream_id);
     } else {
-      nghttp2_submit_rst_stream(session, frame->hd.stream_id, NGHTTP2_CANCEL);
+      spdy->submit_rst_stream(frame->hd.stream_id, NGHTTP2_CANCEL);
     }
   }
   return 0;
@@ -1098,8 +1091,8 @@ int SpdySession::on_connect()
   entry[1].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
   entry[1].value = get_initial_window_size();
 
-  rv = nghttp2_submit_settings
-    (session_, entry, sizeof(entry)/sizeof(nghttp2_settings_entry));
+  rv = nghttp2_submit_settings(session_, NGHTTP2_FLAG_NONE, entry,
+                               sizeof(entry)/sizeof(nghttp2_settings_entry));
   if(rv != 0) {
     return -1;
   }
diff --git a/src/shrpx_spdy_session.h b/src/shrpx_spdy_session.h
index c463f440..c1eb80ab 100644
--- a/src/shrpx_spdy_session.h
+++ b/src/shrpx_spdy_session.h
@@ -68,8 +68,7 @@ public:
                      uint8_t pri, const char **nv,
                      const nghttp2_data_provider *data_prd);
 
-  int submit_rst_stream(SpdyDownstreamConnection *dconn,
-                        int32_t stream_id, nghttp2_error_code error_code);
+  int submit_rst_stream(int32_t stream_id, nghttp2_error_code error_code);
 
   int submit_window_update(SpdyDownstreamConnection *dconn, int32_t amount);
 
diff --git a/tests/nghttp2_session_test.c b/tests/nghttp2_session_test.c
index 71699112..be69a935 100644
--- a/tests/nghttp2_session_test.c
+++ b/tests/nghttp2_session_test.c
@@ -2213,9 +2213,10 @@ void test_nghttp2_submit_priority(void)
                                        NGHTTP2_STREAM_OPENING, NULL);
 
   CU_ASSERT(NGHTTP2_ERR_INVALID_ARGUMENT ==
-            nghttp2_submit_priority(session, 1, -1));
+            nghttp2_submit_priority(session, NGHTTP2_FLAG_NONE, 1, -1));
 
-  CU_ASSERT(0 == nghttp2_submit_priority(session, 1, 1000000007));
+  CU_ASSERT(0 == nghttp2_submit_priority(session, NGHTTP2_FLAG_NONE, 1,
+                                         1000000007));
   CU_ASSERT(1000000007 == stream->pri);
 
   nghttp2_session_del(session);
@@ -2252,7 +2253,7 @@ void test_nghttp2_submit_settings(void)
   nghttp2_session_server_new(&session, &callbacks, &ud);
 
   CU_ASSERT(NGHTTP2_ERR_INVALID_ARGUMENT ==
-            nghttp2_submit_settings(session, iv, 5));
+            nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, 5));
 
   /* Make sure that local settings are not changed */
   CU_ASSERT(NGHTTP2_INITIAL_MAX_CONCURRENT_STREAMS ==
@@ -2263,7 +2264,7 @@ void test_nghttp2_submit_settings(void)
             session->local_settings[NGHTTP2_SETTINGS_FLOW_CONTROL_OPTIONS]);
 
   /* Now sends without 5th one */
-  CU_ASSERT(0 == nghttp2_submit_settings(session, iv, 4));
+  CU_ASSERT(0 == nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, 4));
 
   /* Make sure that local settings are changed */
   CU_ASSERT(50 ==
@@ -2326,7 +2327,7 @@ void test_nghttp2_submit_settings_update_local_window_size(void)
                                        NGHTTP2_STREAM_OPENED, NULL);
   stream->local_flow_control = 0;
 
-  CU_ASSERT(0 == nghttp2_submit_settings(session, iv, 1));
+  CU_ASSERT(0 == nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, 1));
 
   stream = nghttp2_session_get_stream(session, 1);
   CU_ASSERT(0 == stream->recv_window_size);
@@ -2350,7 +2351,7 @@ void test_nghttp2_submit_settings_update_local_window_size(void)
                                        NGHTTP2_PRI_DEFAULT,
                                        NGHTTP2_STREAM_OPENED, NULL);
 
-  CU_ASSERT(0 == nghttp2_submit_settings(session, iv, 2));
+  CU_ASSERT(0 == nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, 2));
   CU_ASSERT(NGHTTP2_INITIAL_WINDOW_SIZE == stream->local_window_size);
 
   nghttp2_session_del(session);
@@ -2363,7 +2364,7 @@ void test_nghttp2_submit_settings_update_local_window_size(void)
                                        NGHTTP2_STREAM_OPENED, NULL);
   stream->local_window_size = NGHTTP2_MAX_WINDOW_SIZE;
 
-  CU_ASSERT(0 == nghttp2_submit_settings(session, iv, 1));
+  CU_ASSERT(0 == nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv, 1));
   CU_ASSERT(NGHTTP2_STREAM_CLOSING == stream->state);
 
   nghttp2_session_del(session);
@@ -2645,7 +2646,7 @@ void test_nghttp2_session_get_next_ob_item(void)
   session->remote_settings[NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS] = 2;
 
   CU_ASSERT(NULL == nghttp2_session_get_next_ob_item(session));
-  nghttp2_submit_ping(session, NULL);
+  nghttp2_submit_ping(session, NGHTTP2_FLAG_NONE, NULL);
   CU_ASSERT(NGHTTP2_PING ==
             OB_CTRL_TYPE(nghttp2_session_get_next_ob_item(session)));
 
@@ -2691,7 +2692,7 @@ void test_nghttp2_session_pop_next_ob_item(void)
   session->remote_settings[NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS] = 1;
 
   CU_ASSERT(NULL == nghttp2_session_pop_next_ob_item(session));
-  nghttp2_submit_ping(session, NULL);
+  nghttp2_submit_ping(session, NGHTTP2_FLAG_NONE, NULL);
   nghttp2_submit_request(session, 1, nv, NULL, NULL);
 
   item = nghttp2_session_pop_next_ob_item(session);
@@ -2908,7 +2909,7 @@ void test_nghttp2_session_defer_data(void)
   CU_ASSERT(ud.data_source_length == 16*1024);
 
   ud.block_count = 1;
-  nghttp2_submit_ping(session, NULL);
+  nghttp2_submit_ping(session, NGHTTP2_FLAG_NONE, NULL);
   /* Sends PING */
   CU_ASSERT(0 == nghttp2_session_send(session));
   CU_ASSERT(NGHTTP2_PING == ud.sent_frame_type);
@@ -3123,7 +3124,7 @@ void test_nghttp2_session_flow_control_disable_local(void)
   iv[0].settings_id = NGHTTP2_SETTINGS_FLOW_CONTROL_OPTIONS;
   iv[0].value = 1;
 
-  CU_ASSERT(0 == nghttp2_submit_settings(session, iv,
+  CU_ASSERT(0 == nghttp2_submit_settings(session, NGHTTP2_FLAG_NONE, iv,
                                          sizeof(iv)/sizeof(iv[0])));
   CU_ASSERT(0 == stream->local_flow_control);
   CU_ASSERT(0 == session->local_flow_control);
@@ -3369,7 +3370,8 @@ void test_nghttp2_session_on_ctrl_not_send(void)
   CU_ASSERT(0 ==
             nghttp2_submit_headers(session, NGHTTP2_FLAG_END_STREAM, 1,
                                    NGHTTP2_PRI_DEFAULT, nv, NULL));
-  CU_ASSERT(0 == nghttp2_submit_rst_stream(session, 1, NGHTTP2_INTERNAL_ERROR));
+  CU_ASSERT(0 == nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, 1,
+                                           NGHTTP2_INTERNAL_ERROR));
   CU_ASSERT(0 == nghttp2_session_send(session));
   CU_ASSERT(1 == user_data.frame_not_send_cb_called);
   CU_ASSERT(NGHTTP2_HEADERS == user_data.not_sent_frame_type);
@@ -3385,7 +3387,8 @@ void test_nghttp2_session_on_ctrl_not_send(void)
   CU_ASSERT(0 ==
             nghttp2_submit_headers(session, NGHTTP2_FLAG_END_STREAM, 3,
                                    NGHTTP2_PRI_DEFAULT, nv, NULL));
-  CU_ASSERT(0 == nghttp2_submit_rst_stream(session, 3, NGHTTP2_INTERNAL_ERROR));
+  CU_ASSERT(0 == nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE, 3,
+                                           NGHTTP2_INTERNAL_ERROR));
   CU_ASSERT(0 == nghttp2_session_send(session));
   CU_ASSERT(1 == user_data.frame_not_send_cb_called);
   CU_ASSERT(NGHTTP2_HEADERS == user_data.not_sent_frame_type);
@@ -3407,11 +3410,12 @@ void test_nghttp2_session_on_ctrl_not_send(void)
 
   /* Send PRIORITY to stream ID = 1 which does not exist */
   CU_ASSERT(NGHTTP2_ERR_STREAM_CLOSED ==
-            nghttp2_submit_priority(session, 1, 0));
+            nghttp2_submit_priority(session, NGHTTP2_FLAG_NONE, 1, 0));
 
   user_data.frame_not_send_cb_called = 0;
   /* Send GOAWAY */
-  CU_ASSERT(0 == nghttp2_submit_goaway(session, NGHTTP2_NO_ERROR, NULL, 0));
+  CU_ASSERT(0 == nghttp2_submit_goaway(session, NGHTTP2_FLAG_NONE,
+                                       NGHTTP2_NO_ERROR, NULL, 0));
   CU_ASSERT(0 == nghttp2_submit_headers(session, NGHTTP2_FLAG_END_STREAM, -1,
                                         NGHTTP2_PRI_DEFAULT, nv, NULL));
   CU_ASSERT(0 == nghttp2_session_send(session));
@@ -3431,10 +3435,11 @@ void test_nghttp2_session_get_outbound_queue_size(void)
   CU_ASSERT(0 == nghttp2_session_client_new(&session, &callbacks, NULL));
   CU_ASSERT(0 == nghttp2_session_get_outbound_queue_size(session));
 
-  CU_ASSERT(0 == nghttp2_submit_ping(session, NULL));
+  CU_ASSERT(0 == nghttp2_submit_ping(session, NGHTTP2_FLAG_NONE, NULL));
   CU_ASSERT(1 == nghttp2_session_get_outbound_queue_size(session));
 
-  CU_ASSERT(0 == nghttp2_submit_goaway(session, NGHTTP2_NO_ERROR, NULL, 0));
+  CU_ASSERT(0 == nghttp2_submit_goaway(session, NGHTTP2_FLAG_NONE,
+                                       NGHTTP2_NO_ERROR, NULL, 0));
   CU_ASSERT(2 == nghttp2_session_get_outbound_queue_size(session));
 
   nghttp2_session_del(session);
@@ -3540,7 +3545,7 @@ void test_nghttp2_session_data_backoff_by_high_pri_frame(void)
   /* data for DATA[1] is read from data_prd but it is not sent */
   CU_ASSERT(ud.data_source_length == 8*1024);
 
-  nghttp2_submit_ping(session, NULL);
+  nghttp2_submit_ping(session, NGHTTP2_FLAG_NONE, NULL);
   ud.block_count = 2;
   /* Sends DATA[1] + PING, PING is interleaved in DATA sequence */
   CU_ASSERT(0 == nghttp2_session_send(session));