zebra: Add ctx to netlink message parsing

Add the initial step of passing in a dplane context
to reading route netlink messages.  This code
will be run in two contexts:

a) The normal pthread for reading netlink messages from
the kernel
b) The dplane_fpm_nl pthread.

The goal of this commit is too just allow a) to work
b) will be filled in in the future.  Effectively
everything should still be working as it should
pre this change.  We will just possibly allow
the passing of the context around( but not used )

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

zebra/rt_netlink.c

@@ -692,8 +692,9 @@ static uint8_t parse_multipath_nexthops_unicast(ns_id_t ns_id,
 }
 
 /* Looking up routing table by netlink interface. */
-static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
-					     int startup)
+int netlink_route_change_read_unicast_internal(struct nlmsghdr *h,
+					       ns_id_t ns_id, int startup,
+					       struct zebra_dplane_ctx *ctx)
 {
 	int len;
 	struct rtmsg *rtm;
@@ -768,9 +769,8 @@ static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
 
 	selfroute = is_selfroute(rtm->rtm_protocol);
 
-	if (!startup && selfroute
-	    && h->nlmsg_type == RTM_NEWROUTE
-	    && !zrouter.asic_offloaded) {
+	if (!startup && selfroute && h->nlmsg_type == RTM_NEWROUTE &&
+	    !zrouter.asic_offloaded && !ctx) {
 		if (IS_ZEBRA_DEBUG_KERNEL)
 			zlog_debug("Route type: %d Received that we think we have originated, ignoring",
 				   rtm->rtm_protocol);
@@ -988,8 +988,8 @@ static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
 			}
 		}
 		if (nhe_id || ng)
-			rib_add_multipath(afi, SAFI_UNICAST, &p, &src_p, re, ng,
-					  startup);
+			dplane_rib_add_multipath(afi, SAFI_UNICAST, &p, &src_p,
+						 re, ng, startup, ctx);
 		else {
 			/*
 			 * I really don't see how this is possible
@@ -1004,6 +1004,13 @@ static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
 			XFREE(MTYPE_RE, re);
 		}
 	} else {
+		if (ctx) {
+			zlog_err(
+				"%s: %pFX RTM_DELROUTE received but received a context as well",
+				__func__, &p);
+			return 0;
+		}
+
 		if (nhe_id) {
 			rib_delete(afi, SAFI_UNICAST, vrf_id, proto, 0, flags,
 				   &p, &src_p, NULL, nhe_id, table, metric,
@@ -1028,7 +1035,14 @@ static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
 		}
 	}
 
-	return 0;
+	return 1;
+}
+
+static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
+					     int startup)
+{
+	return netlink_route_change_read_unicast_internal(h, ns_id, startup,
+							  NULL);
 }
 
 static struct mcast_route_data *mroute = NULL;

zebra/rt_netlink.h

@@ -122,6 +122,10 @@ netlink_put_lsp_update_msg(struct nl_batch *bth, struct zebra_dplane_ctx *ctx);
 extern enum netlink_msg_status
 netlink_put_pw_update_msg(struct nl_batch *bth, struct zebra_dplane_ctx *ctx);
 
+int netlink_route_change_read_unicast_internal(struct nlmsghdr *h,
+					       ns_id_t ns_id, int startup,
+					       struct zebra_dplane_ctx *ctx);
+
 #ifdef NETLINK_DEBUG
 const char *nlmsg_type2str(uint16_t type);
 const char *af_type2str(int type);

zebra/zebra_dplane.c

@@ -6301,6 +6301,17 @@ kernel_dplane_process_ipset_entry(struct zebra_dplane_provider *prov,
 	dplane_provider_enqueue_out_ctx(prov, ctx);
 }
 
+void dplane_rib_add_multipath(afi_t afi, safi_t safi, struct prefix *p,
+			      struct prefix_ipv6 *src_p, struct route_entry *re,
+			      struct nexthop_group *ng, int startup,
+			      struct zebra_dplane_ctx *ctx)
+{
+	if (!ctx)
+		rib_add_multipath(afi, safi, p, src_p, re, ng, startup);
+	else {
+	}
+}
+
 /*
  * Kernel provider callback
  */

zebra/zebra_dplane.h

@@ -1081,6 +1081,16 @@ void zebra_dplane_pre_finish(void);
 void zebra_dplane_finish(void);
 void zebra_dplane_shutdown(void);
 
+/*
+ * decision point for sending a routing update through the old
+ * straight to zebra master pthread or through the dplane to
+ * the master pthread for handling
+ */
+void dplane_rib_add_multipath(afi_t afi, safi_t safi, struct prefix *p,
+			      struct prefix_ipv6 *src_p, struct route_entry *re,
+			      struct nexthop_group *ng, int startup,
+			      struct zebra_dplane_ctx *ctx);
+
 #ifdef __cplusplus
 }
 #endif