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 <ecree.xilinx@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

5 files changed, 33 insertions, 36 deletions

diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index ab979fd11133..ee734b69150f 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -2538,23 +2538,33 @@ static int efx_ef10_filter_table_probe(struct efx_nic *efx)
 
 	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 */
 static inline void
 efx_ef10_build_rx_desc(struct efx_rx_queue *rx_queue, unsigned int index)
@@ -3211,9 +3221,7 @@ static int efx_ef10_vport_set_mac_address(struct efx_nic *efx)
 
 	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)
@@ -3243,9 +3251,7 @@ restore_vadaptor:
 	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;
 
@@ -3275,8 +3281,7 @@ static int efx_ef10_set_mac_address(struct efx_nic *efx)
 	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);
@@ -3286,7 +3291,6 @@ static int efx_ef10_set_mac_address(struct efx_nic *efx)
 				sizeof(inbuf), NULL, 0, NULL);
 
 	efx_ef10_filter_table_probe(efx);
-	up_write(&efx->filter_sem);
 	mutex_unlock(&efx->mac_lock);
 
 	if (was_enabled)
@@ -4092,7 +4096,7 @@ const struct efx_nic_type efx_hunt_a0_vf_nic_type = {
 	.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,
diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index 25cd43e3fcf7..5fe18b383e20 100644
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -375,26 +375,32 @@ static int ef100_filter_table_up(struct efx_nic *efx)
 {
 	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
diff --git a/drivers/net/ethernet/sfc/ef10_sriov.c b/drivers/net/ethernet/sfc/ef10_sriov.c
index 92550c7e85ce..9aae0d8b713f 100644
--- a/drivers/net/ethernet/sfc/ef10_sriov.c
+++ b/drivers/net/ethernet/sfc/ef10_sriov.c
@@ -501,14 +501,11 @@ int efx_ef10_sriov_set_vf_mac(struct efx_nic *efx, int vf_i, const u8 *mac)
 		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);
@@ -539,12 +536,9 @@ int efx_ef10_sriov_set_vf_mac(struct efx_nic *efx, int vf_i, const u8 *mac)
 	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);
 	}
@@ -580,7 +574,6 @@ int efx_ef10_sriov_set_vf_vlan(struct efx_nic *efx, int vf_i, u16 vlan,
 		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);
@@ -654,7 +647,6 @@ restore_filters:
 		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);
@@ -666,10 +658,8 @@ restore_filters:
 	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,
diff --git a/drivers/net/ethernet/sfc/mcdi_filters.h b/drivers/net/ethernet/sfc/mcdi_filters.h
index 06426aa9f2f3..c0d6558b9fd2 100644
--- a/drivers/net/ethernet/sfc/mcdi_filters.h
+++ b/drivers/net/ethernet/sfc/mcdi_filters.h
@@ -89,6 +89,7 @@ struct efx_mcdi_filter_table {
 	 */
 	bool mc_chaining;
 	bool vlan_filter;
+	/* Entries on the vlan_list are added/removed under filter_sem */
 	struct list_head vlan_list;
 };
 
diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c
index bd21d6ac778a..4826e6a7e4ce 100644
--- a/drivers/net/ethernet/sfc/rx_common.c
+++ b/drivers/net/ethernet/sfc/rx_common.c
@@ -793,7 +793,6 @@ int efx_probe_filters(struct efx_nic *efx)
 	int rc;
 
 	mutex_lock(&efx->mac_lock);
-	down_write(&efx->filter_sem);
 	rc = efx->type->filter_table_probe(efx);
 	if (rc)
 		goto out_unlock;
@@ -830,7 +829,6 @@ int efx_probe_filters(struct efx_nic *efx)
 	}
 #endif
 out_unlock:
-	up_write(&efx->filter_sem);
 	mutex_unlock(&efx->mac_lock);
 	return rc;
 }
@@ -846,9 +844,7 @@ void efx_remove_filters(struct efx_nic *efx)
 		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