3 files changed, 121 insertions, 5 deletions

diff --git a/lib/netdev-offload-tc.c b/lib/netdev-offload-tc.c
index 7cdd84944..04b5e218a 100644
--- a/lib/netdev-offload-tc.c
+++ b/lib/netdev-offload-tc.c
@@ -55,6 +55,11 @@ struct netlink_field {
     int size;
 };
 
+struct chain_node {
+    struct hmap_node node;
+    uint32_t chain;
+};
+
 static bool
 is_internal_port(const char *type)
 {
@@ -345,6 +350,69 @@ get_block_id_from_netdev(struct netdev *netdev)
 }
 
 static int
+get_chains_from_netdev(struct netdev *netdev, struct tcf_id *id,
+                       struct hmap *map)
+{
+    struct netdev_flow_dump *dump;
+    struct chain_node *chain_node;
+    struct ofpbuf rbuffer, reply;
+    uint32_t chain;
+    size_t hash;
+    int err;
+
+    dump = xzalloc(sizeof *dump);
+    dump->nl_dump = xzalloc(sizeof *dump->nl_dump);
+    dump->netdev = netdev_ref(netdev);
+
+    ofpbuf_init(&rbuffer, NL_DUMP_BUFSIZE);
+    tc_dump_tc_chain_start(id, dump->nl_dump);
+
+    while (nl_dump_next(dump->nl_dump, &reply, &rbuffer)) {
+        if (parse_netlink_to_tc_chain(&reply, &chain)) {
+            continue;
+        }
+
+        chain_node = xzalloc(sizeof *chain_node);
+        chain_node->chain = chain;
+        hash = hash_int(chain, 0);
+        hmap_insert(map, &chain_node->node, hash);
+    }
+
+    err = nl_dump_done(dump->nl_dump);
+    ofpbuf_uninit(&rbuffer);
+    netdev_close(netdev);
+    free(dump->nl_dump);
+    free(dump);
+
+    return err;
+}
+
+static int
+delete_chains_from_netdev(struct netdev *netdev, struct tcf_id *id)
+{
+    struct chain_node *chain_node;
+    struct hmap map;
+    int error;
+
+    hmap_init(&map);
+    error = get_chains_from_netdev(netdev, id, &map);
+
+    if (!error) {
+        /* Flush rules explicitly needed when we work with ingress_block,
+         * so we will not fail with reattaching block to bond iface, for ex.
+         */
+        HMAP_FOR_EACH_POP (chain_node, node, &map) {
+            id->chain = chain_node->chain;
+            tc_del_filter(id);
+            free(chain_node);
+        }
+    }
+
+    hmap_destroy(&map);
+    return error;
+}
+
+static int
 netdev_tc_flow_flush(struct netdev *netdev)
 {
     struct ufid_tc_data *data, *next;
@@ -1999,6 +2067,7 @@ netdev_tc_init_flow_api(struct netdev *netdev)
 {
     static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
     enum tc_qdisc_hook hook = get_tc_qdisc_hook(netdev);
+    static bool get_chain_supported = true;
     uint32_t block_id = 0;
     struct tcf_id id;
     int ifindex;
@@ -2012,12 +2081,18 @@ netdev_tc_init_flow_api(struct netdev *netdev)
     }
 
     block_id = get_block_id_from_netdev(netdev);
-
-    /* Flush rules explicitly needed when we work with ingress_block,
-     * so we will not fail with reattaching block to bond iface, for ex.
-     */
     id = tc_make_tcf_id(ifindex, block_id, 0, hook);
-    tc_del_filter(&id);
+
+    if (get_chain_supported) {
+        if (delete_chains_from_netdev(netdev, &id)) {
+            get_chain_supported = false;
+        }
+    }
+
+    /* fallback here if delete chains fail */
+    if (!get_chain_supported) {
+        tc_del_filter(&id);
+    }
 
     /* make sure there is no ingress/egress qdisc */
     tc_add_del_qdisc(ifindex, false, 0, hook);
diff --git a/lib/tc.c b/lib/tc.c
index ef3706425..a27cca2cc 100644
--- a/lib/tc.c
+++ b/lib/tc.c
@@ -61,6 +61,10 @@
 #define TCA_DUMP_FLAGS 15
 #endif
 
+#ifndef RTM_GETCHAIN
+#define RTM_GETCHAIN 102
+#endif
+
 VLOG_DEFINE_THIS_MODULE(tc);
 
 static struct vlog_rate_limit error_rl = VLOG_RATE_LIMIT_INIT(60, 5);
@@ -297,6 +301,10 @@ static const struct nl_policy tca_policy[] = {
     [TCA_STATS2] = { .type = NL_A_NESTED, .optional = true, },
 };
 
+static const struct nl_policy tca_chain_policy[] = {
+    [TCA_CHAIN] = { .type = NL_A_U32, .optional = false, },
+};
+
 static const struct nl_policy tca_flower_policy[] = {
     [TCA_FLOWER_CLASSID] = { .type = NL_A_U32, .optional = true, },
     [TCA_FLOWER_INDEV] = { .type = NL_A_STRING, .max_len = IFNAMSIZ,
@@ -1906,6 +1914,25 @@ parse_netlink_to_tc_flower(struct ofpbuf *reply, struct tcf_id *id,
 }
 
 int
+parse_netlink_to_tc_chain(struct ofpbuf *reply, uint32_t *chain)
+{
+    struct nlattr *ta[ARRAY_SIZE(tca_chain_policy)];
+    struct tcmsg *tc;
+
+    tc = ofpbuf_at_assert(reply, NLMSG_HDRLEN, sizeof *tc);
+
+    if (!nl_policy_parse(reply, NLMSG_HDRLEN + sizeof *tc,
+                         tca_chain_policy, ta, ARRAY_SIZE(ta))) {
+        VLOG_ERR_RL(&error_rl, "failed to parse tca chain policy");
+        return EINVAL;
+    }
+
+   *chain = nl_attr_get_u32(ta[TCA_CHAIN]);
+
+    return 0;
+}
+
+int
 tc_dump_flower_start(struct tcf_id *id, struct nl_dump *dump, bool terse)
 {
     struct ofpbuf request;
@@ -1925,6 +1952,18 @@ tc_dump_flower_start(struct tcf_id *id, struct nl_dump *dump, bool terse)
 }
 
 int
+tc_dump_tc_chain_start(struct tcf_id *id, struct nl_dump *dump)
+{
+    struct ofpbuf request;
+
+    request_from_tcf_id(id, 0, RTM_GETCHAIN, NLM_F_DUMP, &request);
+    nl_dump_start(dump, NETLINK_ROUTE, &request);
+    ofpbuf_uninit(&request);
+
+    return 0;
+}
+
+int
 tc_del_filter(struct tcf_id *id)
 {
     struct ofpbuf request;
diff --git a/lib/tc.h b/lib/tc.h
index 2c846eb3a..a147ca461 100644
--- a/lib/tc.h
+++ b/lib/tc.h
@@ -363,10 +363,12 @@ int tc_replace_flower(struct tcf_id *id, struct tc_flower *flower);
 int tc_del_filter(struct tcf_id *id);
 int tc_get_flower(struct tcf_id *id, struct tc_flower *flower);
 int tc_dump_flower_start(struct tcf_id *id, struct nl_dump *dump, bool terse);
+int tc_dump_tc_chain_start(struct tcf_id *id, struct nl_dump *dump);
 int parse_netlink_to_tc_flower(struct ofpbuf *reply,
                                struct tcf_id *id,
                                struct tc_flower *flower,
                                bool terse);
+int parse_netlink_to_tc_chain(struct ofpbuf *reply, uint32_t *chain);
 void tc_set_policy(const char *policy);
 
 #endif /* tc.h */