sfc: move table locking into filter_table_{probe,remove} methods

We need to be able to drop the efx->filter_sem in ef100_filter_table_up()
so that we can call functions that insert filters (and thus take that
rwsem for read), which means the efx->type->filter_table_probe method
needs to be responsible for taking the lock in the first place.

Signed-off-by: Edward Cree <[e-mail]>
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/ethernet/sfc/ef10.c

···
 
 	if (rc)
 		return rc;
+	down_write(&efx->filter_sem);
 	rc = efx_mcdi_filter_table_probe(efx, nic_data->workaround_26807);
 
 	if (rc)
-		return rc;
+		goto out_unlock;
 
 	list_for_each_entry(vlan, &nic_data->vlan_list, list) {
 		rc = efx_mcdi_filter_add_vlan(efx, vlan->vid);
 		if (rc)
 			goto fail_add_vlan;
 	}
-	return 0;
+	goto out_unlock;
 
 fail_add_vlan:
 	efx_mcdi_filter_table_remove(efx);
+out_unlock:
+	up_write(&efx->filter_sem);
 	return rc;
+}
+
+static void efx_ef10_filter_table_remove(struct efx_nic *efx)
+{
+	down_write(&efx->filter_sem);
+	efx_mcdi_filter_table_remove(efx);
+	up_write(&efx->filter_sem);
 }
 
 /* This creates an entry in the RX descriptor queue */
···
 
 	efx_device_detach_sync(efx);
 	efx_net_stop(efx->net_dev);
-	down_write(&efx->filter_sem);
-	efx_mcdi_filter_table_remove(efx);
-	up_write(&efx->filter_sem);
+	efx_ef10_filter_table_remove(efx);
 
 	rc = efx_ef10_vadaptor_free(efx, efx->vport_id);
 	if (rc)
···
 	if (rc2)
 		goto reset_nic;
 restore_filters:
-	down_write(&efx->filter_sem);
 	rc2 = efx_ef10_filter_table_probe(efx);
-	up_write(&efx->filter_sem);
 	if (rc2)
 		goto reset_nic;
 
···
 	efx_net_stop(efx->net_dev);
 
 	mutex_lock(&efx->mac_lock);
-	down_write(&efx->filter_sem);
-	efx_mcdi_filter_table_remove(efx);
+	efx_ef10_filter_table_remove(efx);
 
 	ether_addr_copy(MCDI_PTR(inbuf, VADAPTOR_SET_MAC_IN_MACADDR),
 			efx->net_dev->dev_addr);
···
 				sizeof(inbuf), NULL, 0, NULL);
 
 	efx_ef10_filter_table_probe(efx);
-	up_write(&efx->filter_sem);
 	mutex_unlock(&efx->mac_lock);
 
 	if (was_enabled)
···
 	.ev_test_generate = efx_ef10_ev_test_generate,
 	.filter_table_probe = efx_ef10_filter_table_probe,
 	.filter_table_restore = efx_mcdi_filter_table_restore,
-	.filter_table_remove = efx_mcdi_filter_table_remove,
+	.filter_table_remove = efx_ef10_filter_table_remove,
 	.filter_update_rx_scatter = efx_mcdi_update_rx_scatter,
 	.filter_insert = efx_mcdi_filter_insert,
 	.filter_remove_safe = efx_mcdi_filter_remove_safe,

drivers/net/ethernet/sfc/ef100_nic.c

···
 {
 	int rc;
 
+	down_write(&efx->filter_sem);
 	rc = efx_mcdi_filter_add_vlan(efx, EFX_FILTER_VID_UNSPEC);
-	if (rc) {
-		efx_mcdi_filter_table_down(efx);
-		return rc;
-	}
+	if (rc)
+		goto fail_unspec;
 
 	rc = efx_mcdi_filter_add_vlan(efx, 0);
-	if (rc) {
-		efx_mcdi_filter_del_vlan(efx, EFX_FILTER_VID_UNSPEC);
-		efx_mcdi_filter_table_down(efx);
-	}
+	if (rc)
+		goto fail_vlan0;
+	up_write(&efx->filter_sem);
+	return 0;
 
+fail_vlan0:
+	efx_mcdi_filter_del_vlan(efx, EFX_FILTER_VID_UNSPEC);
+fail_unspec:
+	efx_mcdi_filter_table_down(efx);
+	up_write(&efx->filter_sem);
 	return rc;
 }
 
 static void ef100_filter_table_down(struct efx_nic *efx)
 {
+	down_write(&efx->filter_sem);
 	efx_mcdi_filter_del_vlan(efx, 0);
 	efx_mcdi_filter_del_vlan(efx, EFX_FILTER_VID_UNSPEC);
 	efx_mcdi_filter_table_down(efx);
+	up_write(&efx->filter_sem);
 }
 
 /*	Other

drivers/net/ethernet/sfc/ef10_sriov.c

···
 		efx_device_detach_sync(vf->efx);
 		efx_net_stop(vf->efx->net_dev);
 
-		down_write(&vf->efx->filter_sem);
 		vf->efx->type->filter_table_remove(vf->efx);
 
 		rc = efx_ef10_vadaptor_free(vf->efx, EVB_PORT_ID_ASSIGNED);
-		if (rc) {
-			up_write(&vf->efx->filter_sem);
+		if (rc)
 			return rc;
-		}
 	}
 
 	rc = efx_ef10_evb_port_assign(efx, EVB_PORT_ID_NULL, vf_i);
···
 	if (vf->efx) {
 		/* VF cannot use the vport_id that the PF created */
 		rc = efx_ef10_vadaptor_alloc(vf->efx, EVB_PORT_ID_ASSIGNED);
-		if (rc) {
-			up_write(&vf->efx->filter_sem);
+		if (rc)
 			return rc;
-		}
 		vf->efx->type->filter_table_probe(vf->efx);
-		up_write(&vf->efx->filter_sem);
 		efx_net_open(vf->efx->net_dev);
 		efx_device_attach_if_not_resetting(vf->efx);
 	}
···
 		efx_net_stop(vf->efx->net_dev);
 
 		mutex_lock(&vf->efx->mac_lock);
-		down_write(&vf->efx->filter_sem);
 		vf->efx->type->filter_table_remove(vf->efx);
 
 		rc = efx_ef10_vadaptor_free(vf->efx, EVB_PORT_ID_ASSIGNED);
···
 		if (rc2)
 			goto reset_nic_up_write;
 
-		up_write(&vf->efx->filter_sem);
 		mutex_unlock(&vf->efx->mac_lock);
 
 		rc2 = efx_net_open(vf->efx->net_dev);
···
 	return rc;
 
 reset_nic_up_write:
-	if (vf->efx) {
-		up_write(&vf->efx->filter_sem);
+	if (vf->efx)
 		mutex_unlock(&vf->efx->mac_lock);
-	}
 reset_nic:
 	if (vf->efx) {
 		netif_err(efx, drv, efx->net_dev,

drivers/net/ethernet/sfc/mcdi_filters.h

···
 	 */
 	bool mc_chaining;
 	bool vlan_filter;
+	/* Entries on the vlan_list are added/removed under filter_sem */
 	struct list_head vlan_list;
 };
 

drivers/net/ethernet/sfc/rx_common.c

···
 	int rc;
 
 	mutex_lock(&efx->mac_lock);
-	down_write(&efx->filter_sem);
 	rc = efx->type->filter_table_probe(efx);
 	if (rc)
 		goto out_unlock;
···
 	}
 #endif
 out_unlock:
-	up_write(&efx->filter_sem);
 	mutex_unlock(&efx->mac_lock);
 	return rc;
 }
···
 		channel->rps_flow_id = NULL;
 	}
 #endif
-	down_write(&efx->filter_sem);
 	efx->type->filter_table_remove(efx);
-	up_write(&efx->filter_sem);
 }
 
 #ifdef CONFIG_RFS_ACCEL