northd: Add a new engine 'lr_nat' to manage lr NAT data.

This new engine now maintains the NAT related data for each
logical router which was earlier maintained by the northd
engine node in the 'struct ovn_datapath'.  The input to
this engine node is 'northd'.

A record for each logical router (lr_nat_record) is maintained
in the 'lr_nats' hmap table which stores the lr's NAT dat.

'northd' engine now reports logical routers changed due to NATs
in its tracking data.  'lr_nat' engine node makes use of
this tracked data in its northd change handler to update the
NAT data.

This engine node becomes an input to 'lflow' node.

Acked-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Numan Siddique <numans@ovn.org>
(cherry picked from commit de42956)

lib/ovn-util.c

@@ -385,11 +385,17 @@ extract_sbrec_binding_first_mac(const struct sbrec_port_binding *binding,
 }
 
 bool
-lport_addresses_is_empty(struct lport_addresses *laddrs)
+lport_addresses_is_empty(const struct lport_addresses *laddrs)
 {
     return !laddrs->n_ipv4_addrs && !laddrs->n_ipv6_addrs;
 }
 
+void
+init_lport_addresses(struct lport_addresses *laddrs)
+{
+    *laddrs = (struct lport_addresses) { 0 };
+}
+
 void
 destroy_lport_addresses(struct lport_addresses *laddrs)
 {

lib/ovn-util.h

@@ -112,7 +112,8 @@ bool extract_sbrec_binding_first_mac(const struct sbrec_port_binding *binding,
 bool extract_lrp_networks__(char *mac, char **networks, size_t n_networks,
                             struct lport_addresses *laddrs);
 
-bool lport_addresses_is_empty(struct lport_addresses *);
+bool lport_addresses_is_empty(const struct lport_addresses *);
+void init_lport_addresses(struct lport_addresses *);
 void destroy_lport_addresses(struct lport_addresses *);
 const char *find_lport_address(const struct lport_addresses *laddrs,
                                const char *ip_s);

lib/stopwatch-names.h

@@ -29,5 +29,6 @@
 #define LFLOWS_TO_SB_STOPWATCH_NAME "lflows_to_sb"
 #define PORT_GROUP_RUN_STOPWATCH_NAME "port_group_run"
 #define SYNC_METERS_RUN_STOPWATCH_NAME "sync_meters_run"
+#define LR_NAT_RUN_STOPWATCH_NAME "lr_nat_run"
 
 #endif

northd/automake.mk

@@ -24,6 +24,8 @@ northd_ovn_northd_SOURCES = \
 	northd/en-sync-from-sb.h \
 	northd/en-lb-data.c \
 	northd/en-lb-data.h \
+	northd/en-lr-nat.c \
+	northd/en-lr-nat.h \
 	northd/inc-proc-northd.c \
 	northd/inc-proc-northd.h \
 	northd/ipam.c \

northd/en-lflow.c

@@ -19,6 +19,7 @@
 #include <stdio.h>
 
 #include "en-lflow.h"
+#include "en-lr-nat.h"
 #include "en-northd.h"
 #include "en-meters.h"
 
@@ -40,6 +41,9 @@ lflow_get_input_data(struct engine_node *node,
         engine_get_input_data("port_group", node);
     struct sync_meters_data *sync_meters_data =
         engine_get_input_data("sync_meters", node);
+    struct ed_type_lr_nat_data *lr_nat_data =
+        engine_get_input_data("lr_nat", node);
+
     lflow_input->nbrec_bfd_table =
         EN_OVSDB_GET(engine_get_input("NB_bfd", node));
     lflow_input->sbrec_bfd_table =
@@ -61,6 +65,7 @@ lflow_get_input_data(struct engine_node *node,
     lflow_input->ls_ports = &northd_data->ls_ports;
     lflow_input->lr_ports = &northd_data->lr_ports;
     lflow_input->ls_port_groups = &pg_data->ls_port_groups;
+    lflow_input->lr_nats = &lr_nat_data->lr_nats;
     lflow_input->meter_groups = &sync_meters_data->meter_groups;
     lflow_input->lb_datapaths_map = &northd_data->lb_datapaths_map;
     lflow_input->svc_monitor_map = &northd_data->svc_monitor_map;