From 9b9f4d6007e6383e36e4dc52cdd44c3637ac81de Mon Sep 17 00:00:00 2001
From: Ethan Jackson <ethan@nicira.com>
Date: Mon, 7 Jan 2013 15:48:12 -0800
Subject: [PATCH] tunnels: Remove support for df_inherit from userspace.

This will be required to support flow based tunneling.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
---
 NEWS                 |  2 ++
 lib/netdev-vport.c   |  6 ++----
 vswitchd/vswitch.xml | 14 +++-----------
 3 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/NEWS b/NEWS
index 3f06a7a8b..f9f7171dd 100644
--- a/NEWS
+++ b/NEWS
@@ -17,6 +17,8 @@ post-v1.9.0
         syntax.  OpenFlow 1.1 adds a port named ANY, which introduces a
         conflict.  ANY was rarely used in flow syntax, so we chose to
         retire that meaning of ANY in favor of the OpenFlow 1.1 meaning.
+    - Inheritance of the Don't Fragment bit in IP tunnels (df_inherit) is
+      no longer supported.
 
 
 v1.9.0 - xx xxx xxxx
diff --git a/lib/netdev-vport.c b/lib/netdev-vport.c
index d6c4aa649..b732d06b4 100644
--- a/lib/netdev-vport.c
+++ b/lib/netdev-vport.c
@@ -545,10 +545,6 @@ parse_tunnel_config(const char *name, const char *type,
             if (!strcmp(node->value, "true")) {
                 flags |= TNL_F_CSUM;
             }
-        } else if (!strcmp(node->key, "df_inherit")) {
-            if (!strcmp(node->value, "true")) {
-                flags |= TNL_F_DF_INHERIT;
-            }
         } else if (!strcmp(node->key, "df_default")) {
             if (!strcmp(node->value, "false")) {
                 flags &= ~TNL_F_DF_DEFAULT;
@@ -748,6 +744,8 @@ unparse_tunnel_config(const char *name OVS_UNUSED, const char *type OVS_UNUSED,
         smap_add(args, "csum", "true");
     }
     if (flags & TNL_F_DF_INHERIT) {
+        /* Shouldn't happen as "df_inherit" is no longer supported.  However,
+         * for completeness we report it if it's there. */
         smap_add(args, "df_inherit", "true");
     }
     if (!(flags & TNL_F_DF_DEFAULT)) {
diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml
index a6f8c07cd..18643c20e 100644
--- a/vswitchd/vswitch.xml
+++ b/vswitchd/vswitch.xml
@@ -1400,19 +1400,11 @@
         system default, typically 64).  Default is the system default TTL.
       </column>
 
-      <column name="options" key="df_inherit" type='{"type": "boolean"}'>
-        Optional.  If enabled, the Don't Fragment bit will be copied from the
-        inner IP headers (those of the encapsulated traffic) to the outer
-        (tunnel) headers.  Default is disabled; set to <code>true</code> to
-        enable.
-      </column>
-
       <column name="options" key="df_default"
               type='{"type": "boolean"}'>
-        Optional.  If enabled, the Don't Fragment bit will be set by default on
-        tunnel headers if the <code>df_inherit</code> option is not set, or if
-        the encapsulated packet is not IP.  Default is enabled; set to
-        <code>false</code> to disable.
+        Optional.  If enabled, the Don't Fragment bit will be set on tunnel
+        outer headers to allow path MTU discovery. Default is enabled; set
+        to <code>false</code> to disable.
       </column>
 
       <group title="Tunnel Options: gre and ipsec_gre only">
-- 
2.43.0