compat: add compatibility headers for tc mpls action

OvS includes compat code for several TC actions including vlan, mirred and
tunnel key. MPLS actions have recently been added to TC in the kernel. In
preparation for adding TC offload code for MPLS, add the MPLS compat code.

Signed-off-by: John Hurley <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Signed-off-by: Simon Horman <[email protected]>

acinclude.m4

@@ -192,6 +192,13 @@ AC_DEFUN([OVS_CHECK_LINUX_TC], [
     [AC_DEFINE([HAVE_TCA_VLAN_PUSH_VLAN_PRIORITY], [1],
                [Define to 1 if TCA_VLAN_PUSH_VLAN_PRIORITY is available.])])
 
+  AC_COMPILE_IFELSE([
+    AC_LANG_PROGRAM([#include <linux/tc_act/tc_mpls.h>], [
+        int x = TCA_MPLS_TTL;
+    ])],
+    [AC_DEFINE([HAVE_TCA_MPLS_TTL], [1],
+               [Define to 1 if HAVE_TCA_MPLS_TTL is available.])])
+
   AC_COMPILE_IFELSE([
     AC_LANG_PROGRAM([#include <linux/tc_act/tc_tunnel_key.h>], [
         int x = TCA_TUNNEL_KEY_ENC_TTL;

include/linux/automake.mk

@@ -1,6 +1,7 @@
 noinst_HEADERS += \
 	include/linux/netfilter/nf_conntrack_sctp.h \
 	include/linux/pkt_cls.h \
+	include/linux/tc_act/tc_mpls.h \
 	include/linux/tc_act/tc_pedit.h \
 	include/linux/tc_act/tc_skbedit.h \
 	include/linux/tc_act/tc_tunnel_key.h \

include/linux/tc_act/tc_mpls.h

@@ -0,0 +1,37 @@
+#ifndef __LINUX_TC_ACT_TC_MPLS_WRAPPER_H
+#define __LINUX_TC_ACT_TC_MPLS_WRAPPER_H 1
+
+#if defined(__KERNEL__) || defined(HAVE_TCA_MPLS_TTL)
+#include_next <linux/tc_act/tc_mpls.h>
+#else
+
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2019 Netronome Systems, Inc. */
+
+#define TCA_MPLS_ACT_POP	1
+#define TCA_MPLS_ACT_PUSH	2
+#define TCA_MPLS_ACT_MODIFY	3
+#define TCA_MPLS_ACT_DEC_TTL	4
+
+struct tc_mpls {
+       tc_gen;         /* generic TC action fields. */
+       int m_action;   /* action of type TCA_MPLS_ACT_*. */
+};
+
+enum {
+       TCA_MPLS_UNSPEC,
+       TCA_MPLS_TM,    /* struct tcf_t; time values associated with action. */
+       TCA_MPLS_PARMS, /* struct tc_mpls; action type and general TC fields. */
+       TCA_MPLS_PAD,
+       TCA_MPLS_PROTO, /* be16; eth_type of pushed or next (for pop) header. */
+       TCA_MPLS_LABEL, /* u32; MPLS label. Lower 20 bits are used. */
+       TCA_MPLS_TC,    /* u8; MPLS TC field. Lower 3 bits are used. */
+       TCA_MPLS_TTL,   /* u8; MPLS TTL field. Must not be 0. */
+       TCA_MPLS_BOS,   /* u8; MPLS BOS field. Either 1 or 0. */
+       __TCA_MPLS_MAX,
+};
+#define TCA_MPLS_MAX (__TCA_MPLS_MAX - 1)
+
+#endif /* __KERNEL__ || HAVE_TCA_MPLS_TTL */
+
+#endif /* __LINUX_TC_ACT_TC_MPLS_WRAPPER_H */