zebra: uplink tracking and startup delay for EVPN-MH

Local ethernet segments are held in a protodown or error-disabled state
if access to the VxLAN overlay is not ready -
1. When FRR comes up the local-ESs/access-port are kept protodown
for the startup-delay duration. During this time the underlay and
EVPN routes via it are expected to converge.
2. When all the uplinks/core-links attached to the underlay go down
the access-ports are similarly protodowned.

The ES-bond protodown state is propagated to each ES-bond member
and programmed in the dataplane/kernel (per-bond-member).

Configuring uplinks -
vtysh -c "conf t" vtysh -c "interface swp4" vtysh -c "evpn mh uplink"

Configuring startup delay -
vtysh -c "conf t" vtysh -c "evpn mh startup-delay 100"

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
EVPN protodown display -
========================
root@torm-11:mgmt:~# vtysh -c "show evpn"
L2 VNIs: 10
L3 VNIs: 3
Advertise gateway mac-ip: No
Advertise svi mac-ip: No
Duplicate address detection: Disable
  Detection max-moves 5, time 180
EVPN MH:
  mac-holdtime: 60s, neigh-holdtime: 60s
  startup-delay: 180s, start-delay-timer: 00:01:14 <<<<<<<<<<<<
  uplink-cfg-cnt: 4, uplink-active-cnt: 4
  protodown: startup-delay <<<<<<<<<<<<<<<<<<<<<<<
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
ES-bond protodown display -
===========================
root@torm-11:mgmt:~# vtysh -c "show interface hostbond1"
Interface hostbond1 is up, line protocol is down
  Link ups:       0    last: (never)
  Link downs:     1    last: 2020/04/26 20:38:03.53
  PTM status: disabled
  vrf: default
  OS Description: Local Node/s torm-11 and Ports swp5 <==> Remote  Node/s hostd-11 and Ports swp1
  index 58 metric 0 mtu 9152 speed 4294967295
  flags: <UP,BROADCAST,MULTICAST>
  Type: Ethernet
  HWaddr: 00:02:00:00:00:35
  Interface Type bond
  Master interface: bridge
  EVPN-MH: ES id 1 ES sysmac 00:00:00:00:01:11
  protodown: off rc: startup-delay  <<<<<<<<<<<<<<<<<
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
ES-bond member protodown display -
==================================
root@torm-11:mgmt:~# vtysh -c "show interface swp5"
Interface swp5 is up, line protocol is down
  Link ups:       0    last: (never)
  Link downs:     3    last: 2020/04/26 20:38:03.52
  PTM status: disabled
  vrf: default
  index 7 metric 0 mtu 9152 speed 10000
  flags: <UP,BROADCAST,MULTICAST>
  Type: Ethernet
  HWaddr: 00:02:00:00:00:35
  Interface Type Other
  Master interface: hostbond1
  protodown: on rc: startup-delay <<<<<<<<<<<<<<<<
root@torm-11:mgmt:~#
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>

1 files changed, 89 insertions, 13 deletions

diff --git a/zebra/zebra_l2.c b/zebra/zebra_l2.c
index 19d8bfd733..c1ad91c8ca 100644
--- a/zebra/zebra_l2.c
+++ b/zebra/zebra_l2.c
@@ -41,6 +41,7 @@
 #include "zebra/zebra_memory.h"
 #include "zebra/zebra_vrf.h"
 #include "zebra/rt_netlink.h"
+#include "zebra/interface.h"
 #include "zebra/zebra_l2.h"
 #include "zebra/zebra_vxlan.h"
 #include "zebra/zebra_evpn_mh.h"
@@ -109,24 +110,99 @@ void zebra_l2_unmap_slave_from_bridge(struct zebra_l2info_brslave *br_slave)
 	br_slave->br_if = NULL;
 }
 
-void zebra_l2_map_slave_to_bond(struct zebra_l2info_bondslave *bond_slave,
-				vrf_id_t vrf_id)
+void zebra_l2_map_slave_to_bond(struct zebra_if *zif, vrf_id_t vrf_id)
 {
 	struct interface *bond_if;
+	struct zebra_if *bond_zif;
+	struct zebra_l2info_bondslave *bond_slave = &zif->bondslave_info;
 
-	/* TODO: Handle change of master */
 	bond_if = if_lookup_by_index_all_vrf(bond_slave->bond_ifindex);
-	if (bond_if)
-		bond_slave->bond_if = bond_if;
-	else
-		bond_slave->bond_if = if_create_ifindex(bond_slave->bond_ifindex,
-							vrf_id);
+	if (bond_if == bond_slave->bond_if)
+		return;
+
+	/* unlink the slave from the old master */
+	zebra_l2_unmap_slave_from_bond(zif);
+
+	/* If the bond is present and ready link the bond-member
+	 * to it
+	 */
+	if (bond_if && (bond_zif = bond_if->info)) {
+		if (bond_zif->bond_info.mbr_zifs) {
+			if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+				zlog_debug("bond mbr %s linked to %s",
+					   zif->ifp->name, bond_if->name);
+			bond_slave->bond_if = bond_if;
+			/* link the slave to the new bond master */
+			listnode_add(bond_zif->bond_info.mbr_zifs, zif);
+			/* inherit protodown flags from the es-bond */
+			if (zebra_evpn_is_es_bond(bond_if))
+				zebra_evpn_mh_update_protodown_bond_mbr(
+					zif, false /*clear*/, __func__);
+		}
+	} else {
+		if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+			zlog_debug("bond mbr %s link to bond skipped",
+				   zif->ifp->name);
+	}
+}
+
+void zebra_l2_unmap_slave_from_bond(struct zebra_if *zif)
+{
+	struct zebra_l2info_bondslave *bond_slave = &zif->bondslave_info;
+	struct zebra_if *bond_zif;
+
+	if (!bond_slave->bond_if) {
+		if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+			zlog_debug("bond mbr %s unlink from bond skipped",
+				   zif->ifp->name);
+		return;
+	}
+
+	if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+		zlog_debug("bond mbr %s un-linked from %s", zif->ifp->name,
+			   bond_slave->bond_if->name);
+
+	/* unlink the slave from the bond master */
+	bond_zif = bond_slave->bond_if->info;
+	/* clear protodown flags */
+	if (zebra_evpn_is_es_bond(bond_zif->ifp))
+		zebra_evpn_mh_update_protodown_bond_mbr(zif, true /*clear*/,
+							__func__);
+	listnode_delete(bond_zif->bond_info.mbr_zifs, zif);
+	bond_slave->bond_if = NULL;
 }
 
-void zebra_l2_unmap_slave_from_bond(struct zebra_l2info_bondslave *bond_slave)
+void zebra_l2if_update_bond(struct interface *ifp, bool add)
 {
-	if (bond_slave != NULL)
-		bond_slave->bond_if = NULL;
+	struct zebra_if *zif;
+	struct zebra_l2info_bond *bond;
+
+	zif = ifp->info;
+	assert(zif);
+	bond = &zif->bond_info;
+
+	if (add) {
+		if (!bond->mbr_zifs) {
+			if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+				zlog_debug("bond %s mbr list create",
+					   ifp->name);
+			bond->mbr_zifs = list_new();
+		}
+	} else {
+		struct listnode *node;
+		struct listnode *nnode;
+		struct zebra_if *bond_mbr;
+
+		if (!bond->mbr_zifs)
+			return;
+
+		if (IS_ZEBRA_DEBUG_EVPN_MH_ES || IS_ZEBRA_DEBUG_EVENT)
+			zlog_debug("bond %s mbr list delete", ifp->name);
+		for (ALL_LIST_ELEMENTS(bond->mbr_zifs, node, nnode, bond_mbr))
+			zebra_l2_unmap_slave_from_bond(bond_mbr);
+
+		list_delete(&bond->mbr_zifs);
+	}
 }
 
 /*
@@ -318,9 +394,9 @@ void zebra_l2if_update_bond_slave(struct interface *ifp, ifindex_t bond_ifindex)
 
 	/* Set up or remove link with master */
 	if (bond_ifindex != IFINDEX_INTERNAL)
-		zebra_l2_map_slave_to_bond(&zif->bondslave_info, ifp->vrf_id);
+		zebra_l2_map_slave_to_bond(zif, ifp->vrf_id);
 	else if (old_bond_ifindex != IFINDEX_INTERNAL)
-		zebra_l2_unmap_slave_from_bond(&zif->bondslave_info);
+		zebra_l2_unmap_slave_from_bond(zif);
 }
 
 void zebra_vlan_bitmap_compute(struct interface *ifp,