[PATCH net-next v3 3/9] net: marvell: prestera: Add strict cleanup of fib arbiter

[Yevhen Orlov <yevhen.orlov@plvision.eu>]

This will, ensure, that there is no more, preciously allocated fib_cache
entries left after deinit.
Will be used to free allocated resources of nexthop routes, that points
to "not our" port (e.g. eth0).

Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
---
 .../marvell/prestera/prestera_router.c        | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_router.c b/drivers/net/ethernet/marvell/prestera/prestera_router.c
index e9b08b541aba..41955c7f8323 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_router.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_router.c
@@ -334,6 +334,49 @@ prestera_k_arb_fib_evt(struct prestera_switch *sw,
 	return 0;
 }
 
+static void __prestera_k_arb_abort_fib(struct prestera_switch *sw)
+{
+	struct prestera_kern_fib_cache *fib_cache;
+	struct rhashtable_iter iter;
+
+	while (1) {
+		rhashtable_walk_enter(&sw->router->kern_fib_cache_ht, &iter);
+		rhashtable_walk_start(&iter);
+
+		fib_cache = rhashtable_walk_next(&iter);
+
+		rhashtable_walk_stop(&iter);
+		rhashtable_walk_exit(&iter);
+
+		if (!fib_cache) {
+			break;
+		} else if (IS_ERR(fib_cache)) {
+			continue;
+		} else if (fib_cache) {
+			__prestera_k_arb_fib_lpm_offload_set(sw, fib_cache,
+							     false, false,
+							     false);
+			/* No need to destroy lpm.
+			 * It will be aborted by destroy_ht
+			 */
+			prestera_kern_fib_cache_destroy(sw, fib_cache);
+		}
+	}
+}
+
+static void prestera_k_arb_abort(struct prestera_switch *sw)
+{
+	/* Function to remove all arbiter entries and related hw objects. */
+	/* Sequence:
+	 *   1) Clear arbiter tables, but don't touch hw
+	 *   2) Clear hw
+	 * We use such approach, because arbiter object is not directly mapped
+	 * to hw. So deletion of one arbiter object may even lead to creation of
+	 * hw object (e.g. in case of overlapped routes).
+	 */
+	__prestera_k_arb_abort_fib(sw);
+}
+
 static int __prestera_inetaddr_port_event(struct net_device *port_dev,
 					  unsigned long event,
 					  struct netlink_ext_ack *extack)
@@ -600,6 +643,9 @@ void prestera_router_fini(struct prestera_switch *sw)
 	unregister_fib_notifier(&init_net, &sw->router->fib_nb);
 	unregister_inetaddr_notifier(&sw->router->inetaddr_nb);
 	unregister_inetaddr_validator_notifier(&sw->router->inetaddr_valid_nb);
+
+	prestera_k_arb_abort(sw);
+
 	kfree(sw->router->nhgrp_hw_state_cache);
 	rhashtable_destroy(&sw->router->kern_fib_cache_ht);
 	prestera_router_hw_fini(sw);
-- 
2.17.1