sfc: insert default MAE rules to connect VFs to representors

Default rules are low-priority switching rules which the hardware uses
 in the absence of higher-priority rules.  Each representor requires a
 corresponding rule matching traffic from its representee VF and
 delivering to the PF (where a check on INGRESS_MPORT in
 __ef100_rx_packet() will direct it to the representor).  No rule is
 required in the reverse direction, because representor TX uses a TX
 override descriptor to bypass the MAE and deliver directly to the VF.
Since inserting any rule into the MAE disables the firmware's own
 default rules, also insert a pair of rules to connect the PF to the
 physical network port and vice-versa.

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

drivers/net/ethernet/sfc/Makefile

@@ -8,7 +8,8 @@ sfc-y			+= efx.o efx_common.o efx_channels.o nic.o \
 			   ef100.o ef100_nic.o ef100_netdev.o \
 			   ef100_ethtool.o ef100_rx.o ef100_tx.o
 sfc-$(CONFIG_SFC_MTD)	+= mtd.o
-sfc-$(CONFIG_SFC_SRIOV)	+= sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o mae.o
+sfc-$(CONFIG_SFC_SRIOV)	+= sriov.o ef10_sriov.o ef100_sriov.o ef100_rep.o \
+                           mae.o tc.o
 
 obj-$(CONFIG_SFC)	+= sfc.o
 

drivers/net/ethernet/sfc/ef100.c

@@ -431,6 +431,9 @@ static void ef100_pci_remove(struct pci_dev *pci_dev)
 
 	probe_data = container_of(efx, struct efx_probe_data, efx);
 	ef100_remove_netdev(probe_data);
+#ifdef CONFIG_SFC_SRIOV
+	efx_fini_struct_tc(efx);
+#endif
 
 	ef100_remove(efx);
 	efx_fini_io(efx);

drivers/net/ethernet/sfc/ef100_netdev.c

@@ -329,6 +329,10 @@ void ef100_remove_netdev(struct efx_probe_data *probe_data)
 
 	ef100_unregister_netdev(efx);
 
+#ifdef CONFIG_SFC_SRIOV
+	efx_fini_tc(efx);
+#endif
+
 	down_write(&efx->filter_sem);
 	efx_mcdi_filter_table_remove(efx);
 	up_write(&efx->filter_sem);

drivers/net/ethernet/sfc/ef100_nic.c

@@ -1094,12 +1094,29 @@ int ef100_probe_netdev_pf(struct efx_nic *efx)
 		return 0;
 
 #ifdef CONFIG_SFC_SRIOV
+	rc = efx_init_struct_tc(efx);
+	if (rc)
+		return rc;
+
 	rc = efx_ef100_get_base_mport(efx);
 	if (rc) {
 		netif_warn(efx, probe, net_dev,
 			   "Failed to probe base mport rc %d; representors will not function\n",
 			   rc);
 	}
+
+	rc = efx_init_tc(efx);
+	if (rc) {
+		/* Either we don't have an MAE at all (i.e. legacy v-switching),
+		 * or we do but we failed to probe it.  In the latter case, we
+		 * may not have set up default rules, in which case we won't be
+		 * able to pass any traffic.  However, we don't fail the probe,
+		 * because the user might need to use the netdevice to apply
+		 * configuration changes to fix whatever's wrong with the MAE.
+		 */
+		netif_warn(efx, probe, net_dev, "Failed to probe MAE rc %d\n",
+			   rc);
+	}
 #endif
 	return 0;
 

drivers/net/ethernet/sfc/ef100_rep.c

@@ -27,6 +27,8 @@ static int efx_ef100_rep_init_struct(struct efx_nic *efx, struct efx_rep *efv,
 	efv->parent = efx;
 	efv->idx = i;
 	INIT_LIST_HEAD(&efv->list);
+	efv->dflt.fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
+	INIT_LIST_HEAD(&efv->dflt.acts.list);
 	INIT_LIST_HEAD(&efv->rx_list);
 	spin_lock_init(&efv->rx_lock);
 	efv->msg_enable = NETIF_MSG_DRV | NETIF_MSG_PROBE |
@@ -212,7 +214,14 @@ static int efx_ef100_configure_rep(struct efx_rep *efv)
 	/* mport label should fit in 16 bits */
 	WARN_ON(efv->mport >> 16);
 
-	return 0;
+	return efx_tc_configure_default_rule_rep(efv);
+}
+
+static void efx_ef100_deconfigure_rep(struct efx_rep *efv)
+{
+	struct efx_nic *efx = efv->parent;
+
+	efx_tc_deconfigure_default_rule(efx, &efv->dflt);
 }
 
 static void efx_ef100_rep_destroy_netdev(struct efx_rep *efv)
@@ -246,19 +255,21 @@ int efx_ef100_vfrep_create(struct efx_nic *efx, unsigned int i)
 		pci_err(efx->pci_dev,
 			"Failed to configure representor for VF %d, rc %d\n",
 			i, rc);
-		goto fail;
+		goto fail1;
 	}
 	rc = register_netdev(efv->net_dev);
 	if (rc) {
 		pci_err(efx->pci_dev,
 			"Failed to register representor for VF %d, rc %d\n",
 			i, rc);
-		goto fail;
+		goto fail2;
 	}
 	pci_dbg(efx->pci_dev, "Representor for VF %d is %s\n", i,
 		efv->net_dev->name);
 	return 0;
-fail:
+fail2:
+	efx_ef100_deconfigure_rep(efv);
+fail1:
 	efx_ef100_rep_destroy_netdev(efv);
 	return rc;
 }
@@ -272,6 +283,7 @@ void efx_ef100_vfrep_destroy(struct efx_nic *efx, struct efx_rep *efv)
 		return;
 	netif_dbg(efx, drv, rep_dev, "Removing VF representor\n");
 	unregister_netdev(rep_dev);
+	efx_ef100_deconfigure_rep(efv);
 	efx_ef100_rep_destroy_netdev(efv);
 }
 

drivers/net/ethernet/sfc/ef100_rep.h

@@ -14,6 +14,7 @@
 #define EF100_REP_H
 
 #include "net_driver.h"
+#include "tc.h"
 
 struct efx_rep_sw_stats {
 	atomic64_t rx_packets, tx_packets;
@@ -32,6 +33,7 @@ struct efx_rep_sw_stats {
  * @write_index: number of packets enqueued to @rx_list
  * @read_index: number of packets consumed from @rx_list
  * @rx_pring_size: max length of RX list
+ * @dflt: default-rule for MAE switching
  * @list: entry on efx->vf_reps
  * @rx_list: list of SKBs queued for receive in NAPI poll
  * @rx_lock: protects @rx_list
@@ -46,6 +48,7 @@ struct efx_rep {
 	unsigned int idx;
 	unsigned int write_index, read_index;
 	unsigned int rx_pring_size;
+	struct efx_tc_flow_rule dflt;
 	struct list_head list;
 	struct list_head rx_list;
 	spinlock_t rx_lock;