bnxt_en: fix dst/src fid for vxlan encap/decap actions

For flows that involve a vxlan encap action, the vxlan sock
interface may be specified as the outgoing interface. The driver
must resolve the outgoing PF interface used by this socket and
use the dst_fid of the PF in the hwrm_cfa_encap_record_alloc cmd.

Similarily for flows that have a vxlan decap action, the
fid of the incoming PF interface must be used as the src_fid in
the hwrm_cfa_decap_filter_alloc cmd.

Fixes: 8c95f773 ("bnxt_en: add support for Flower based vxlan encap/decap offload")
Signed-off-by: Sathya Perla <sathya.perla@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c

@@ -56,7 +56,6 @@ static int bnxt_tc_parse_redir(struct bnxt *bp,
 {
 	int ifindex = tcf_mirred_ifindex(tc_act);
 	struct net_device *dev;
-	u16 dst_fid;
 
 	dev = __dev_get_by_index(dev_net(bp->dev), ifindex);
 	if (!dev) {
@@ -64,15 +63,7 @@ static int bnxt_tc_parse_redir(struct bnxt *bp,
 		return -EINVAL;
 	}
 
-	/* find the FID from dev */
-	dst_fid = bnxt_flow_get_dst_fid(bp, dev);
-	if (dst_fid == BNXT_FID_INVALID) {
-		netdev_info(bp->dev, "can't get fid for ifindex=%d", ifindex);
-		return -EINVAL;
-	}
-
 	actions->flags |= BNXT_TC_ACTION_FLAG_FWD;
-	actions->dst_fid = dst_fid;
 	actions->dst_dev = dev;
 	return 0;
 }
@@ -160,14 +151,18 @@ static int bnxt_tc_parse_actions(struct bnxt *bp,
 	if (rc)
 		return rc;
 
-	/* Tunnel encap/decap action must be accompanied by a redirect action */
-	if ((actions->flags & BNXT_TC_ACTION_FLAG_TUNNEL_ENCAP ||
-	     actions->flags & BNXT_TC_ACTION_FLAG_TUNNEL_DECAP) &&
-	    !(actions->flags & BNXT_TC_ACTION_FLAG_FWD)) {
-		netdev_info(bp->dev,
-			    "error: no redir action along with encap/decap");
+	if (actions->flags & BNXT_TC_ACTION_FLAG_FWD) {
+		if (actions->flags & BNXT_TC_ACTION_FLAG_TUNNEL_ENCAP) {
+			/* dst_fid is PF's fid */
+			actions->dst_fid = bp->pf.fw_fid;
+		} else {
+			/* find the FID from dst_dev */
+			actions->dst_fid =
+				bnxt_flow_get_dst_fid(bp, actions->dst_dev);
+			if (actions->dst_fid == BNXT_FID_INVALID)
 				return -EINVAL;
 		}
+	}
 
 	return rc;
 }
@@ -899,10 +894,10 @@ static void bnxt_tc_put_decap_handle(struct bnxt *bp,
 
 static int bnxt_tc_resolve_tunnel_hdrs(struct bnxt *bp,
 				       struct ip_tunnel_key *tun_key,
-				       struct bnxt_tc_l2_key *l2_info,
-				       struct net_device *real_dst_dev)
+				       struct bnxt_tc_l2_key *l2_info)
 {
 #ifdef CONFIG_INET
+	struct net_device *real_dst_dev = bp->dev;
 	struct flowi4 flow = { {0} };
 	struct net_device *dst_dev;
 	struct neighbour *nbr;
@@ -1006,7 +1001,7 @@ static int bnxt_tc_get_decap_handle(struct bnxt *bp, struct bnxt_tc_flow *flow,
 	 */
 	tun_key.u.ipv4.dst = flow->tun_key.u.ipv4.src;
 	tun_key.tp_dst = flow->tun_key.tp_dst;
-	rc = bnxt_tc_resolve_tunnel_hdrs(bp, &tun_key, &l2_info, bp->dev);
+	rc = bnxt_tc_resolve_tunnel_hdrs(bp, &tun_key, &l2_info);
 	if (rc)
 		goto put_decap;
 
@@ -1092,8 +1087,7 @@ static int bnxt_tc_get_encap_handle(struct bnxt *bp, struct bnxt_tc_flow *flow,
 	if (encap_node->tunnel_handle != INVALID_TUNNEL_HANDLE)
 		goto done;
 
-	rc = bnxt_tc_resolve_tunnel_hdrs(bp, encap_key, &encap_node->l2_info,
-					 flow->actions.dst_dev);
+	rc = bnxt_tc_resolve_tunnel_hdrs(bp, encap_key, &encap_node->l2_info);
 	if (rc)
 		goto put_encap;
 
@@ -1166,6 +1160,15 @@ static int __bnxt_tc_del_flow(struct bnxt *bp,
 	return 0;
 }
 
+static void bnxt_tc_set_src_fid(struct bnxt *bp, struct bnxt_tc_flow *flow,
+				u16 src_fid)
+{
+	if (flow->actions.flags & BNXT_TC_ACTION_FLAG_TUNNEL_DECAP)
+		flow->src_fid = bp->pf.fw_fid;
+	else
+		flow->src_fid = src_fid;
+}
+
 /* Add a new flow or replace an existing flow.
  * Notes on locking:
  * There are essentially two critical sections here.
@@ -1201,7 +1204,8 @@ static int bnxt_tc_add_flow(struct bnxt *bp, u16 src_fid,
 	rc = bnxt_tc_parse_flow(bp, tc_flow_cmd, flow);
 	if (rc)
 		goto free_node;
-	flow->src_fid = src_fid;
+
+	bnxt_tc_set_src_fid(bp, flow, src_fid);
 
 	if (!bnxt_tc_can_offload(bp, flow)) {
 		rc = -ENOSPC;