nfp: add repr_preclean callback

Just before a repr is cleaned up, we give the app a chance to perform
some preclean configuration while the reprs pointer is still configured
for the app.

Signed-off-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_app.h

@@ -77,6 +77,8 @@ extern const struct nfp_app_type app_flower;
  * @vnic_init:	vNIC netdev was registered
  * @vnic_clean:	vNIC netdev about to be unregistered
  * @repr_init:	representor about to be registered
+ * @repr_preclean:	representor about to unregistered, executed before app
+ *			reference to the it is removed
  * @repr_clean:	representor about to be unregistered
  * @repr_open:	representor netdev open callback
  * @repr_stop:	representor netdev stop callback
@@ -112,6 +114,7 @@ struct nfp_app_type {
 	void (*vnic_clean)(struct nfp_app *app, struct nfp_net *nn);
 
 	int (*repr_init)(struct nfp_app *app, struct net_device *netdev);
+	void (*repr_preclean)(struct nfp_app *app, struct net_device *netdev);
 	void (*repr_clean)(struct nfp_app *app, struct net_device *netdev);
 
 	int (*repr_open)(struct nfp_app *app, struct nfp_repr *repr);
@@ -225,6 +228,13 @@ nfp_app_repr_init(struct nfp_app *app, struct net_device *netdev)
 	return app->type->repr_init(app, netdev);
 }
 
+static inline void
+nfp_app_repr_preclean(struct nfp_app *app, struct net_device *netdev)
+{
+	if (app->type->repr_preclean)
+		app->type->repr_preclean(app, netdev);
+}
+
 static inline void
 nfp_app_repr_clean(struct nfp_app *app, struct net_device *netdev)
 {

drivers/net/ethernet/netronome/nfp/nfp_net_repr.c

@@ -377,11 +377,22 @@ nfp_reprs_clean_and_free_by_type(struct nfp_app *app,
 				 enum nfp_repr_type type)
 {
 	struct nfp_reprs *reprs;
+	int i;
 
-	reprs = nfp_app_reprs_set(app, type, NULL);
+	reprs = rcu_dereference_protected(app->reprs[type],
+					  lockdep_is_held(&app->pf->lock));
 	if (!reprs)
 		return;
 
+	/* Preclean must happen before we remove the reprs reference from the
+	 * app below.
+	 */
+	for (i = 0; i < reprs->num_reprs; i++)
+		if (reprs->reprs[i])
+			nfp_app_repr_preclean(app, reprs->reprs[i]);
+
+	reprs = nfp_app_reprs_set(app, type, NULL);
+
 	synchronize_rcu();
 	nfp_reprs_clean_and_free(reprs);
 }
@@ -420,8 +431,10 @@ int nfp_reprs_resync_phys_ports(struct nfp_app *app)
 			continue;
 
 		repr = netdev_priv(old_reprs->reprs[i]);
-		if (repr->port->type == NFP_PORT_INVALID)
+		if (repr->port->type == NFP_PORT_INVALID) {
+			nfp_app_repr_preclean(app, old_reprs->reprs[i]);
 			continue;
+		}
 
 		reprs->reprs[i] = old_reprs->reprs[i];
 	}
@@ -438,7 +451,6 @@ int nfp_reprs_resync_phys_ports(struct nfp_app *app)
 		if (repr->port->type != NFP_PORT_INVALID)
 			continue;
 
-		nfp_app_repr_stop(app, repr);
 		nfp_repr_clean(repr);
 	}