netdev-tc-offloads: Add support for IP fragmentation

Add support for frag no, first and later.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Shahar Klein <shahark@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>

acinclude.m4

@@ -178,10 +178,10 @@ dnl Configure Linux tc compat.
 AC_DEFUN([OVS_CHECK_LINUX_TC], [
   AC_COMPILE_IFELSE([
     AC_LANG_PROGRAM([#include <linux/pkt_cls.h>], [
-        int x = TCA_FLOWER_KEY_IP_TTL_MASK;
+        int x = TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST;
     ])],
-    [AC_DEFINE([HAVE_TCA_FLOWER_KEY_IP_TTL_MASK], [1],
+    [AC_DEFINE([HAVE_TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST], [1],
-               [Define to 1 if TCA_FLOWER_KEY_IP_TTL_MASK is avaiable.])])
+               [Define to 1 if TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST is avaiable.])])
 
   AC_COMPILE_IFELSE([
     AC_LANG_PROGRAM([#include <linux/tc_act/tc_vlan.h>], [

include/linux/pkt_cls.h

@@ -1,7 +1,7 @@
 #ifndef __LINUX_PKT_CLS_WRAPPER_H
 #define __LINUX_PKT_CLS_WRAPPER_H 1
 
-#if defined(__KERNEL__) || defined(HAVE_TCA_FLOWER_KEY_IP_TTL_MASK)
+#if defined(__KERNEL__) || defined(HAVE_TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST)
 #include_next <linux/pkt_cls.h>
 #else
 
@@ -201,8 +201,9 @@ enum {
 
 enum {
 	TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT = (1 << 0),
+	TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST = (1 << 1),
 };
 
-#endif /* __KERNEL__ || !HAVE_TCA_FLOWER_KEY_IP_TTL_MASK */
+#endif /* __KERNEL__ || !HAVE_TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST */
 
 #endif /* __LINUX_PKT_CLS_WRAPPER_H */

lib/netdev-tc-offloads.c

@@ -428,6 +428,27 @@ parse_tc_flower_to_match(struct tc_flower *flower,
 
         match_set_nw_ttl_masked(match, key->ip_ttl, mask->ip_ttl);
 
+        if (mask->flags) {
+            uint8_t flags = 0;
+            uint8_t flags_mask = 0;
+
+            if (mask->flags & TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT) {
+                if (key->flags & TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT) {
+                    flags |= FLOW_NW_FRAG_ANY;
+                }
+                flags_mask |= FLOW_NW_FRAG_ANY;
+            }
+
+            if (mask->flags & TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST) {
+                if (!(key->flags & TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST)) {
+                    flags |= FLOW_NW_FRAG_LATER;
+                }
+                flags_mask |= FLOW_NW_FRAG_LATER;
+            }
+
+            match_set_nw_frag_masked(match, flags, flags_mask);
+        }
+
         match_set_nw_src_masked(match, key->ipv4.ipv4_src, mask->ipv4.ipv4_src);
         match_set_nw_dst_masked(match, key->ipv4.ipv4_dst, mask->ipv4.ipv4_dst);
 
@@ -780,11 +801,6 @@ test_key_and_mask(struct match *match)
         return EOPNOTSUPP;
     }
 
-    if (mask->nw_frag) {
-        VLOG_DBG_RL(&rl, "offloading attribute nw_frag isn't supported");
-        return EOPNOTSUPP;
-    }
-
     for (int i = 0; i < FLOW_MAX_MPLS_LABELS; i++) {
         if (mask->mpls_lse[i]) {
             VLOG_DBG_RL(&rl, "offloading attribute mpls_lse isn't supported");
@@ -932,6 +948,17 @@ netdev_tc_flow_put(struct netdev *netdev, struct match *match,
         flower.key.ip_ttl = key->nw_ttl;
         flower.mask.ip_ttl = mask->nw_ttl;
 
+        if (mask->nw_frag) {
+            if (key->nw_frag & FLOW_NW_FRAG_ANY)
+                flower.key.flags |= TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT;
+            if (!(key->nw_frag & FLOW_NW_FRAG_LATER))
+                flower.key.flags |= TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST;
+
+            flower.mask.flags |= TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT;
+            flower.mask.flags |= TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST;
+            mask->nw_frag = 0;
+        }
+
         if (key->nw_proto == IPPROTO_TCP) {
             flower.key.tcp_dst = key->tp_dst;
             flower.mask.tcp_dst = mask->tp_dst;
@@ -958,7 +985,6 @@ netdev_tc_flow_put(struct netdev *netdev, struct match *match,
             mask->tp_dst = 0;
         }
 
-        mask->nw_frag = 0;
         mask->nw_tos = 0;
         mask->nw_proto = 0;
         mask->nw_ttl = 0;

lib/tc.c

@@ -281,6 +281,8 @@ static const struct nl_policy tca_flower_policy[] = {
                                            .optional = true, },
     [TCA_FLOWER_KEY_ENC_UDP_DST_PORT] = { .type = NL_A_U16,
                                           .optional = true, },
+    [TCA_FLOWER_KEY_FLAGS] = { .type = NL_A_BE32, .optional = true, },
+    [TCA_FLOWER_KEY_FLAGS_MASK] = { .type = NL_A_BE32, .optional = true, },
     [TCA_FLOWER_KEY_IP_TTL] = { .type = NL_A_U8,
                                 .optional = true, },
     [TCA_FLOWER_KEY_IP_TTL_MASK] = { .type = NL_A_U8,
@@ -374,6 +376,11 @@ nl_parse_flower_ip(struct nlattr **attrs, struct tc_flower *flower) {
         mask->ip_proto = UINT8_MAX;
     }
 
+    if (attrs[TCA_FLOWER_KEY_FLAGS_MASK]) {
+        key->flags = ntohl(nl_attr_get_u32(attrs[TCA_FLOWER_KEY_FLAGS]));
+        mask->flags = ntohl(nl_attr_get_u32(attrs[TCA_FLOWER_KEY_FLAGS_MASK]));
+    }
+
     if (attrs[TCA_FLOWER_KEY_IPV4_SRC_MASK]) {
         key->ipv4.ipv4_src =
             nl_attr_get_be32(attrs[TCA_FLOWER_KEY_IPV4_SRC]);
@@ -1495,6 +1502,13 @@ nl_msg_put_flower_options(struct ofpbuf *request, struct tc_flower *flower)
                           flower->key.ip_proto);
         }
 
+        if (flower->mask.flags) {
+            nl_msg_put_u32(request, TCA_FLOWER_KEY_FLAGS,
+                           htonl(flower->key.flags));
+            nl_msg_put_u32(request, TCA_FLOWER_KEY_FLAGS_MASK,
+                           htonl(flower->mask.flags));
+        }
+
         if (flower->key.ip_proto == IPPROTO_UDP) {
             FLOWER_PUT_MASKED_VALUE(udp_src, TCA_FLOWER_KEY_UDP_SRC);
             FLOWER_PUT_MASKED_VALUE(udp_dst, TCA_FLOWER_KEY_UDP_DST);

lib/tc.h

@@ -92,6 +92,7 @@ struct tc_flower_key {
 
     ovs_be16 encap_eth_type;
 
+    uint8_t flags;
     uint8_t ip_ttl;
 
     struct {