sfc: some plumbing towards TC encap action offload

Create software objects to manage the metadata for encap actions that
 can be attached to TC rules.  However, since we don't yet have the
 neighbouring information (needed to generate the Ethernet header),
 all rules with encap actions are marked as "unready" and thus insert
 the fallback action into hardware rather than actually offloading the
 encapsulation action.

Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 102 insertions, 2 deletions

diff --git a/drivers/net/ethernet/sfc/tc.c b/drivers/net/ethernet/sfc/tc.c
index 24c67a163910..4177feced3e6 100644
--- a/drivers/net/ethernet/sfc/tc.c
+++ b/drivers/net/ethernet/sfc/tc.c
@@ -14,11 +14,12 @@
 #include <net/geneve.h>
 #include "tc.h"
 #include "tc_bindings.h"
+#include "tc_encap_actions.h"
 #include "mae.h"
 #include "ef100_rep.h"
 #include "efx.h"
 
-static enum efx_encap_type efx_tc_indr_netdev_type(struct net_device *net_dev)
+enum efx_encap_type efx_tc_indr_netdev_type(struct net_device *net_dev)
 {
 	if (netif_is_vxlan(net_dev))
 		return EFX_ENCAP_TYPE_VXLAN;
@@ -111,6 +112,8 @@ static void efx_tc_free_action_set(struct efx_nic *efx,
 	}
 	if (act->count)
 		efx_tc_flower_put_counter_index(efx, act->count);
+	if (act->encap_md)
+		efx_tc_flower_release_encap_md(efx, act->encap_md);
 	kfree(act);
 }
 
@@ -594,6 +597,7 @@ enum efx_tc_action_order {
 	EFX_TC_AO_VLAN_POP,
 	EFX_TC_AO_VLAN_PUSH,
 	EFX_TC_AO_COUNT,
+	EFX_TC_AO_ENCAP,
 	EFX_TC_AO_DELIVER
 };
 /* Determine whether we can add @new action without violating order */
@@ -623,6 +627,10 @@ static bool efx_tc_flower_action_order_ok(const struct efx_tc_action_set *act,
 		if (act->count)
 			return false;
 		fallthrough;
+	case EFX_TC_AO_ENCAP:
+		if (act->encap_md)
+			return false;
+		fallthrough;
 	case EFX_TC_AO_DELIVER:
 		return !act->deliver;
 	default:
@@ -918,11 +926,13 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
 {
 	struct flow_rule *fr = flow_cls_offload_flow_rule(tc);
 	struct netlink_ext_ack *extack = tc->common.extack;
+	const struct ip_tunnel_info *encap_info = NULL;
 	struct efx_tc_flow_rule *rule = NULL, *old;
 	struct efx_tc_action_set *act = NULL;
 	const struct flow_action_entry *fa;
 	struct efx_rep *from_efv, *to_efv;
 	struct efx_tc_match match;
+	u32 acts_id;
 	s64 rc;
 	int i;
 
@@ -1087,6 +1097,46 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
 		case FLOW_ACTION_MIRRED:
 			save = *act;
 
+			if (encap_info) {
+				struct efx_tc_encap_action *encap;
+
+				if (!efx_tc_flower_action_order_ok(act,
+								   EFX_TC_AO_ENCAP)) {
+					rc = -EOPNOTSUPP;
+					NL_SET_ERR_MSG_MOD(extack, "Encap action violates action order");
+					goto release;
+				}
+				encap = efx_tc_flower_create_encap_md(
+						efx, encap_info, fa->dev, extack);
+				if (IS_ERR_OR_NULL(encap)) {
+					rc = PTR_ERR(encap);
+					if (!rc)
+						rc = -EIO; /* arbitrary */
+					goto release;
+				}
+				act->encap_md = encap;
+				act->dest_mport = encap->dest_mport;
+				act->deliver = 1;
+				rc = efx_mae_alloc_action_set(efx, act);
+				if (rc) {
+					NL_SET_ERR_MSG_MOD(extack, "Failed to write action set to hw (encap)");
+					goto release;
+				}
+				list_add_tail(&act->list, &rule->acts.list);
+				act = NULL;
+				if (fa->id == FLOW_ACTION_REDIRECT)
+					break; /* end of the line */
+				/* Mirror, so continue on with saved act */
+				save.count = NULL;
+				act = kzalloc(sizeof(*act), GFP_USER);
+				if (!act) {
+					rc = -ENOMEM;
+					goto release;
+				}
+				*act = save;
+				break;
+			}
+
 			if (!efx_tc_flower_action_order_ok(act, EFX_TC_AO_DELIVER)) {
 				/* can't happen */
 				rc = -EOPNOTSUPP;
@@ -1150,6 +1200,37 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
 			act->vlan_proto[act->vlan_push] = fa->vlan.proto;
 			act->vlan_push++;
 			break;
+		case FLOW_ACTION_TUNNEL_ENCAP:
+			if (encap_info) {
+				/* Can't specify encap multiple times.
+				 * If you want to overwrite an existing
+				 * encap_info, use an intervening
+				 * FLOW_ACTION_TUNNEL_DECAP to clear it.
+				 */
+				NL_SET_ERR_MSG_MOD(extack, "Tunnel key set when already set");
+				rc = -EINVAL;
+				goto release;
+			}
+			if (!fa->tunnel) {
+				NL_SET_ERR_MSG_MOD(extack, "Tunnel key set is missing key");
+				rc = -EOPNOTSUPP;
+				goto release;
+			}
+			encap_info = fa->tunnel;
+			break;
+		case FLOW_ACTION_TUNNEL_DECAP:
+			if (encap_info) {
+				encap_info = NULL;
+				break;
+			}
+			/* Since we don't support enc_key matches on ingress
+			 * (and if we did there'd be no tunnel-device to give
+			 * us a type), we can't offload a decap that's not
+			 * just undoing a previous encap action.
+			 */
+			NL_SET_ERR_MSG_MOD(extack, "Cannot offload tunnel decap action without tunnel device");
+			rc = -EOPNOTSUPP;
+			goto release;
 		default:
 			NL_SET_ERR_MSG_FMT_MOD(extack, "Unhandled action %u",
 					       fa->id);
@@ -1193,8 +1274,21 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
 		NL_SET_ERR_MSG_MOD(extack, "Failed to write action set list to hw");
 		goto release;
 	}
+	if (from_efv == EFX_EFV_PF)
+		/* PF netdev, so rule applies to traffic from wire */
+		rule->fallback = &efx->tc->facts.pf;
+	else
+		/* repdev, so rule applies to traffic from representee */
+		rule->fallback = &efx->tc->facts.reps;
+	if (!efx_tc_check_ready(efx, rule)) {
+		netif_dbg(efx, drv, efx->net_dev, "action not ready for hw\n");
+		acts_id = rule->fallback->fw_id;
+	} else {
+		netif_dbg(efx, drv, efx->net_dev, "ready for hw\n");
+		acts_id = rule->acts.fw_id;
+	}
 	rc = efx_mae_insert_rule(efx, &rule->match, EFX_TC_PRIO_TC,
-				 rule->acts.fw_id, &rule->fw_id);
+				 acts_id, &rule->fw_id);
 	if (rc) {
 		NL_SET_ERR_MSG_MOD(extack, "Failed to insert rule in hw");
 		goto release_acts;
@@ -1609,6 +1703,9 @@ int efx_init_struct_tc(struct efx_nic *efx)
 
 	mutex_init(&efx->tc->mutex);
 	init_waitqueue_head(&efx->tc->flush_wq);
+	rc = efx_tc_init_encap_actions(efx);
+	if (rc < 0)
+		goto fail_encap_actions;
 	rc = efx_tc_init_counters(efx);
 	if (rc < 0)
 		goto fail_counters;
@@ -1635,6 +1732,8 @@ fail_match_action_ht:
 fail_encap_match_ht:
 	efx_tc_destroy_counters(efx);
 fail_counters:
+	efx_tc_destroy_encap_actions(efx);
+fail_encap_actions:
 	mutex_destroy(&efx->tc->mutex);
 	kfree(efx->tc->caps);
 fail_alloc_caps:
@@ -1662,6 +1761,7 @@ void efx_fini_struct_tc(struct efx_nic *efx)
 	rhashtable_free_and_destroy(&efx->tc->encap_match_ht,
 				    efx_tc_encap_match_free, NULL);
 	efx_tc_fini_counters(efx);
+	efx_tc_fini_encap_actions(efx);
 	mutex_unlock(&efx->tc->mutex);
 	mutex_destroy(&efx->tc->mutex);
 	kfree(efx->tc->caps);