ice: enforce interface eligibility and add messaging for SRIOV LAG

Implement checks on what interfaces are eligible for supporting SRIOV VFs
when a member of an aggregate interface.

Implement unwind path for interfaces that become ineligible.

checks for the SRIOV LAG feature bit wrap most of the functional code for
manipulating resources that apply to this feature.  Utilize this bit
to track compliant aggregates.  Also flag any new entries into the
aggregate as not supporting SRIOV LAG for the time they are in the
non-compliant aggregate.

Once an aggregate has been flagged as non-compliant, only unpopulating the
aggregate and re-populating it will return SRIOV LAG functionality.

Reviewed-by: Daniel Machon <daniel.machon@microchip.com>
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice_lag.c

@@ -889,6 +889,7 @@ static void ice_lag_link(struct ice_lag *lag)
 
 	lag->bonded = true;
 	lag->role = ICE_LAG_UNSET;
+	netdev_info(lag->netdev, "Shared SR-IOV resources in bond are active\n");
 }
 
 /**
@@ -1333,6 +1334,7 @@ ice_lag_chk_comp(struct ice_lag *lag, void *ptr)
 	struct netdev_notifier_bonding_info *info;
 	struct netdev_bonding_info *bonding_info;
 	struct list_head *tmp;
+	struct device *dev;
 	int count = 0;
 
 	if (!lag->primary)
@@ -1345,11 +1347,21 @@ ice_lag_chk_comp(struct ice_lag *lag, void *ptr)
 	if (event_upper != lag->upper_netdev)
 		return true;
 
+	dev = ice_pf_to_dev(lag->pf);
+
+	/* only supporting switchdev mode for SRIOV VF LAG.
+	 * primary interface has to be in switchdev mode
+	 */
+	if (!ice_is_switchdev_running(lag->pf)) {
+		dev_info(dev, "Primary interface not in switchdev mode - VF LAG disabled\n");
+		return false;
+	}
+
 	info = (struct netdev_notifier_bonding_info *)ptr;
 	bonding_info = &info->bonding_info;
 	lag->bond_mode = bonding_info->master.bond_mode;
 	if (lag->bond_mode != BOND_MODE_ACTIVEBACKUP) {
-		netdev_info(lag->netdev, "Bond Mode not ACTIVE-BACKUP\n");
+		dev_info(dev, "Bond Mode not ACTIVE-BACKUP - VF LAG disabled\n");
 		return false;
 	}
 
@@ -1359,17 +1371,19 @@ ice_lag_chk_comp(struct ice_lag *lag, void *ptr)
 		struct ice_netdev_priv *peer_np;
 		struct net_device *peer_netdev;
 		struct ice_vsi *vsi, *peer_vsi;
+		struct ice_pf *peer_pf;
 
 		entry = list_entry(tmp, struct ice_lag_netdev_list, node);
 		peer_netdev = entry->netdev;
 		if (!netif_is_ice(peer_netdev)) {
-			netdev_info(lag->netdev, "Found non-ice netdev in LAG\n");
+			dev_info(dev, "Found %s non-ice netdev in LAG - VF LAG disabled\n",
+				 netdev_name(peer_netdev));
 			return false;
 		}
 
 		count++;
 		if (count > 2) {
-			netdev_info(lag->netdev, "Found more than two netdevs in LAG\n");
+			dev_info(dev, "Found more than two netdevs in LAG - VF LAG disabled\n");
 			return false;
 		}
 
@@ -1378,15 +1392,24 @@ ice_lag_chk_comp(struct ice_lag *lag, void *ptr)
 		peer_vsi = peer_np->vsi;
 		if (lag->pf->pdev->bus != peer_vsi->back->pdev->bus ||
 		    lag->pf->pdev->slot != peer_vsi->back->pdev->slot) {
-			netdev_info(lag->netdev, "Found netdev on different device in LAG\n");
+			dev_info(dev, "Found %s on different device in LAG - VF LAG disabled\n",
+				 netdev_name(peer_netdev));
 			return false;
 		}
 
 		dcb_cfg = &vsi->port_info->qos_cfg.local_dcbx_cfg;
 		peer_dcb_cfg = &peer_vsi->port_info->qos_cfg.local_dcbx_cfg;
 		if (memcmp(dcb_cfg, peer_dcb_cfg,
 			   sizeof(struct ice_dcbx_cfg))) {
-			netdev_info(lag->netdev, "Found netdev with different DCB config in LAG\n");
+			dev_info(dev, "Found %s with different DCB in LAG - VF LAG disabled\n",
+				 netdev_name(peer_netdev));
+			return false;
+		}
+
+		peer_pf = peer_vsi->back;
+		if (test_bit(ICE_FLAG_FW_LLDP_AGENT, peer_pf->flags)) {
+			dev_warn(dev, "Found %s with FW LLDP agent active - VF LAG disabled\n",
+				 netdev_name(peer_netdev));
 			return false;
 		}
 	}
@@ -1459,6 +1482,58 @@ ice_lag_monitor_rdma(struct ice_lag *lag, void *ptr)
 		ice_set_rdma_cap(lag->pf);
 }
 
+/**
+ * ice_lag_chk_disabled_bond - monitor interfaces entering/leaving disabled bond
+ * @lag: lag info struct
+ * @ptr: opaque data containing event
+ *
+ * as interfaces enter a bond - determine if the bond is currently
+ * SRIOV LAG compliant and flag if not.  As interfaces leave the
+ * bond, reset their compliant status.
+ */
+static void ice_lag_chk_disabled_bond(struct ice_lag *lag, void *ptr)
+{
+	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
+	struct netdev_notifier_changeupper_info *info = ptr;
+	struct ice_lag *prim_lag;
+
+	if (netdev != lag->netdev)
+		return;
+
+	if (info->linking) {
+		prim_lag = ice_lag_find_primary(lag);
+		if (prim_lag &&
+		    !ice_is_feature_supported(prim_lag->pf, ICE_F_SRIOV_LAG)) {
+			ice_clear_feature_support(lag->pf, ICE_F_SRIOV_LAG);
+			netdev_info(netdev, "Interface added to non-compliant SRIOV LAG aggregate\n");
+		}
+	} else {
+		ice_lag_init_feature_support_flag(lag->pf);
+	}
+}
+
+/**
+ * ice_lag_disable_sriov_bond - set members of bond as not supporting SRIOV LAG
+ * @lag: primary interfaces lag struct
+ */
+static void ice_lag_disable_sriov_bond(struct ice_lag *lag)
+{
+	struct ice_lag_netdev_list *entry;
+	struct ice_netdev_priv *np;
+	struct net_device *netdev;
+	struct list_head *tmp;
+	struct ice_pf *pf;
+
+	list_for_each(tmp, lag->netdev_head) {
+		entry = list_entry(tmp, struct ice_lag_netdev_list, node);
+		netdev = entry->netdev;
+		np = netdev_priv(netdev);
+		pf = np->vsi->back;
+
+		ice_clear_feature_support(pf, ICE_F_SRIOV_LAG);
+	}
+}
+
 /**
  * ice_lag_process_event - process a task assigned to the lag_wq
  * @work: pointer to work_struct
@@ -1480,6 +1555,7 @@ static void ice_lag_process_event(struct work_struct *work)
 	switch (lag_work->event) {
 	case NETDEV_CHANGEUPPER:
 		info = &lag_work->info.changeupper_info;
+		ice_lag_chk_disabled_bond(lag_work->lag, info);
 		if (ice_is_feature_supported(pf, ICE_F_SRIOV_LAG)) {
 			ice_lag_monitor_link(lag_work->lag, info);
 			ice_lag_changeupper_event(lag_work->lag, info);
@@ -1491,6 +1567,9 @@ static void ice_lag_process_event(struct work_struct *work)
 		if (ice_is_feature_supported(pf, ICE_F_SRIOV_LAG)) {
 			if (!ice_lag_chk_comp(lag_work->lag,
 					      &lag_work->info.bonding_info)) {
+				netdev = lag_work->info.bonding_info.info.dev;
+				ice_lag_disable_sriov_bond(lag_work->lag);
+				ice_lag_unregister(lag_work->lag, netdev);
 				goto lag_cleanup;
 			}
 			ice_lag_monitor_active(lag_work->lag,