Handle pna_main_parser_input_metadata_t fields in the tc backend's parser

backends/tc/ebpfCodeGen.cpp

@@ -767,6 +767,24 @@ void PnaStateTranslationVisitor::compileExtractField(const IR::Expression *expr,
     builder->newline();
 }
 
+bool PnaStateTranslationVisitor::preorder(const IR::Member *m) {
+    if ((m->expr != nullptr) && (m->expr->type != nullptr)) {
+        if (auto st = m->expr->type->to<IR::Type_Struct>()) {
+            if (st->name == "pna_main_parser_input_metadata_t") {
+                if (m->member.name == "input_port") {
+                    builder->append("skb->ifindex");
+                    return false;
+                } else {
+                    ::P4::error(ErrorType::ERR_UNSUPPORTED_ON_TARGET,
+                                "%1%: this metadata field is not supported", m);
+                }
+            }
+        }
+    }
+
+    return EBPF::PsaStateTranslationVisitor::preorder(m);
+}
+
 void PnaStateTranslationVisitor::compileLookahead(const IR::Expression *destination) {
     cstring msgStr = absl::StrFormat("Parser: lookahead for %s %s",
                                      state->parser->typeMap->getType(destination)->toString(),

backends/tc/ebpfCodeGen.h

@@ -126,6 +126,8 @@ class PnaStateTranslationVisitor : public EBPF::PsaStateTranslationVisitor {
                                         EBPF::EBPFPsaParser *prsr)
         : EBPF::PsaStateTranslationVisitor(refMap, typeMap, prsr) {}
 
+    bool preorder(const IR::Member *expression) override;
+
  protected:
     void compileExtractField(const IR::Expression *expr, const IR::StructField *field,
                              unsigned hdrOffsetBits, EBPF::EBPFType *type) override;

p4include/tc/pna.p4

@@ -590,6 +590,7 @@ enum PNA_Source_t {
 struct pna_main_parser_input_metadata_t {
     // common fields initialized for all packets that are input to main
     // parser, regardless of direction.
+    // Unsupported as of now.
     bool                     recirculated;
     // If this packet has FROM_NET source, input_port contains
     // the id of the network port on which the packet arrived.

testdata/p4tc_samples/digest_parser_meta.p4

@@ -0,0 +1,144 @@
+/* -*- P4_16 -*- */
+
+#include <core.p4>
+#include <tc/pna.p4>
+
+struct my_ingress_metadata_t {
+    @tc_type("dev") PortId_t ingress_port;
+}
+
+/*
+ * CONST VALUES FOR TYPES
+ */
+const bit<8> IP_PROTO_TCP = 0x06;
+const bit<16> ETHERTYPE_IPV4 = 0x0800;
+
+/*
+ * Standard ethernet header
+ */
+header ethernet_t {
+    @tc_type("macaddr") bit<48> dstAddr;
+    @tc_type("macaddr") bit<48> srcAddr;
+    bit<16> etherType;
+}
+
+header ipv4_t {
+    bit<4>  version;
+    bit<4>  ihl;
+    bit<8>  diffserv;
+    bit<16> totalLen;
+    bit<16> identification;
+    bit<3>  flags;
+    bit<13> fragOffset;
+    bit<8>  ttl;
+    bit<8>  protocol;
+    bit<16> hdrChecksum;
+    @tc_type("ipv4") bit<32> srcAddr;
+    @tc_type("ipv4") bit<32> dstAddr;
+}
+
+struct my_ingress_headers_t {
+    ethernet_t   ethernet;
+    ipv4_t       ipv4;
+}
+
+    /***********************  P A R S E R  **************************/
+parser Ingress_Parser(
+        packet_in pkt,
+        out   my_ingress_headers_t  hdr,
+        inout my_ingress_metadata_t meta,
+        in    pna_main_parser_input_metadata_t istd)
+{
+
+    state start {
+        transition parse_ethernet;
+    }
+
+    state parse_ethernet {
+        pkt.extract(hdr.ethernet);
+        transition select(hdr.ethernet.etherType) {
+            ETHERTYPE_IPV4: parse_ipv4;
+            default: reject;
+        }
+    }
+    state parse_ipv4 {
+        pkt.extract(hdr.ipv4);
+        meta.ingress_port = istd.input_port; 
+        transition accept;
+    }
+}
+
+#define L3_TABLE_SIZE 2048
+
+struct ipv4_learn_digest_t {
+    @tc_type("ipv4") bit<32> srcAddr;
+    @tc_type("dev") PortId_t ingress_port;
+};
+
+/***************** M A T C H - A C T I O N  *********************/
+
+control ingress(
+    inout my_ingress_headers_t  hdr,
+    inout my_ingress_metadata_t meta,
+    in    pna_main_input_metadata_t  istd,
+    inout pna_main_output_metadata_t ostd
+)
+{
+   action send_nh(@tc_type("dev") PortId_t port, @tc_type("macaddr") bit<48> srcMac, @tc_type("macaddr") bit<48> dstMac) {
+        hdr.ethernet.srcAddr = srcMac;
+        hdr.ethernet.dstAddr = dstMac;
+        send_to_port(port);
+   }
+
+   action drop() {
+        drop_packet();
+   }
+
+    table nh_table {
+        key = {
+            hdr.ipv4.dstAddr : exact @tc_type("ipv4") @name("dstAddr");
+        }
+        actions = {
+            send_nh;
+            drop;
+        }
+        size = L3_TABLE_SIZE;
+        const default_action = drop;
+    }
+
+    apply {
+        if (hdr.ipv4.isValid()) {
+            nh_table.apply();
+        }
+    }
+}
+
+    /*********************  D E P A R S E R  ************************/
+
+control Ingress_Deparser(
+    packet_out pkt,
+    inout    my_ingress_headers_t hdr,
+    in    my_ingress_metadata_t meta,
+    in    pna_main_output_metadata_t ostd)
+{
+   Digest<ipv4_learn_digest_t>() digest_inst;
+
+   apply {
+       ipv4_learn_digest_t ipv4_learn_digest;
+
+       pkt.emit(hdr.ethernet);
+       pkt.emit(hdr.ipv4);
+
+       ipv4_learn_digest.srcAddr = hdr.ipv4.srcAddr;
+       ipv4_learn_digest.ingress_port = meta.ingress_port;
+       digest_inst.pack(ipv4_learn_digest);
+   }
+}
+
+/************ F I N A L   P A C K A G E ******************************/
+
+PNA_NIC(
+    Ingress_Parser(),
+    ingress(),
+    Ingress_Deparser()
+) main;

testdata/p4tc_samples_outputs/digest_parser_meta.json

@@ -0,0 +1,98 @@
+{
+  "schema_version" : "1.0.0",
+  "pipeline_name" : "digest_parser_meta",
+  "externs" : [
+    {
+      "name" : "Digest",
+      "id" : "0x05000000",
+      "permissions" : "0x19b6",
+      "instances" : [
+        {
+          "inst_name" : "Ingress_Deparser.digest_inst",
+          "inst_id" : 1,
+          "params" : [
+            {
+              "id" : 1,
+              "name" : "index",
+              "type" : "bit32",
+              "attr" : "tc_key",
+              "bitwidth" : 32
+            },
+            {
+              "id" : 2,
+              "name" : "srcAddr",
+              "type" : "ipv4",
+              "attr" : "param",
+              "bitwidth" : 32
+            },
+            {
+              "id" : 3,
+              "name" : "ingress_port",
+              "type" : "dev",
+              "attr" : "param",
+              "bitwidth" : 32
+            }
+          ]
+        }
+      ]
+    }
+  ],
+  "tables" : [
+    {
+      "name" : "ingress/nh_table",
+      "id" : 1,
+      "tentries" : 2048,
+      "permissions" : "0x3da4",
+      "nummask" : 8,
+      "keysize" : 32,
+      "keyfields" : [
+        {
+          "id" : 1,
+          "name" : "dstAddr",
+          "type" : "ipv4",
+          "match_type" : "exact",
+          "bitwidth" : 32
+        }
+      ],
+      "actions" : [
+        {
+          "id" : 1,
+          "name" : "ingress/send_nh",
+          "action_scope" : "TableAndDefault",
+          "annotations" : [],
+          "params" : [
+            {
+              "id" : 1,
+              "name" : "port",
+              "type" : "dev",
+              "bitwidth" : 32
+            },
+            {
+              "id" : 2,
+              "name" : "srcMac",
+              "type" : "macaddr",
+              "bitwidth" : 48
+            },
+            {
+              "id" : 3,
+              "name" : "dstMac",
+              "type" : "macaddr",
+              "bitwidth" : 48
+            }
+          ],
+          "default_hit_action" : false,
+          "default_miss_action" : false
+        },
+        {
+          "id" : 2,
+          "name" : "ingress/drop",
+          "action_scope" : "TableAndDefault",
+          "annotations" : [],
+          "params" : [],
+          "default_hit_action" : false,
+          "default_miss_action" : true
+        }
+      ]
+    }
+  ]
+}

testdata/p4tc_samples_outputs/digest_parser_meta.template

@@ -0,0 +1,30 @@
+#!/bin/bash -x
+
+set -e
+
+: "${TC:="tc"}"
+$TC p4template create pipeline/digest_parser_meta numtables 1
+
+$TC p4template create action/digest_parser_meta/ingress/send_nh actid 1 \
+	param port type dev \
+	param srcMac type macaddr \
+	param dstMac type macaddr
+$TC p4template update action/digest_parser_meta/ingress/send_nh state active
+
+$TC p4template create action/digest_parser_meta/ingress/drop actid 2
+$TC p4template update action/digest_parser_meta/ingress/drop state active
+
+$TC p4template create extern/root/Digest extid 0x05000000 numinstances 1 tc_acl 0x19b6 has_exec_method
+
+$TC p4template create extern_inst/digest_parser_meta/Digest/Ingress_Deparser.digest_inst instid 1 \
+tc_numel 0 \
+control_path tc_key index ptype bit32 id 1 param srcAddr ptype ipv4 id 2 param ingress_port ptype dev id 3
+
+$TC p4template create table/digest_parser_meta/ingress/nh_table \
+	tblid 1 \
+	type exact \
+	keysz 32 permissions 0x3da4 tentries 2048 nummasks 1 \
+	table_acts act name digest_parser_meta/ingress/send_nh \
+	act name digest_parser_meta/ingress/drop
+$TC p4template update table/digest_parser_meta/ingress/nh_table default_miss_action permissions 0x1024 action digest_parser_meta/ingress/drop
+$TC p4template update pipeline/digest_parser_meta state ready