nr,gnb,stack: add bearer manager to gNB stack to correctly map between eps bearer ids and lcids

lib/include/srsran/common/bearer_manager.h

@@ -18,8 +18,8 @@
 #include "srsran/common/rwlock_guard.h"
 #include "srsran/srslog/srslog.h"
 #include <map>
-#include <unordered_map>
 #include <stdint.h>
+#include <unordered_map>
 
 namespace srsran {
 
@@ -139,6 +139,7 @@ public:
   using radio_bearer_t = srsran::detail::ue_bearer_manager_impl::radio_bearer_t;
 
   enb_bearer_manager();
+  ~enb_bearer_manager();
 
   /// Multi-user interface (see comments above)
   void           add_eps_bearer(uint16_t rnti, uint8_t eps_bearer_id, srsran::srsran_rat_t rat, uint32_t lcid);

lib/src/common/bearer_manager.cc

@@ -113,6 +113,8 @@ namespace srsenb {
 
 enb_bearer_manager::enb_bearer_manager() : logger(srslog::fetch_basic_logger("STCK", false)) {}
 
+enb_bearer_manager::~enb_bearer_manager() {}
+
 void enb_bearer_manager::add_eps_bearer(uint16_t rnti, uint8_t eps_bearer_id, srsran::srsran_rat_t rat, uint32_t lcid)
 {
   auto user_it = users_map.find(rnti);

srsgnb/hdr/stack/gnb_stack_nr.h

@@ -33,6 +33,8 @@ namespace srsenb {
 
 class ngap;
 class gtpu;
+class enb_bearer_manager;
+class gtpu_pdcp_adapter_nr;
 
 struct gnb_stack_args_t {
   stack_log_args_t log;
@@ -153,6 +155,9 @@ private:
   std::unique_ptr<srsenb::gtpu> gtpu;
   // std::unique_ptr<sdap> m_sdap;
 
+  std::unique_ptr<enb_bearer_manager>   bearer_manager;
+  std::unique_ptr<gtpu_pdcp_adapter_nr> gtpu_adapter;
+
   // state
   std::atomic<bool> running = {false};
 };

srsgnb/hdr/stack/rrc/rrc_nr.h

@@ -37,6 +37,8 @@
 
 namespace srsenb {
 
+class enb_bearer_manager;
+
 enum class rrc_nr_state_t { RRC_IDLE, RRC_INACTIVE, RRC_CONNECTED };
 
 class rrc_nr final : public rrc_interface_pdcp_nr,
@@ -55,7 +57,7 @@ public:
                rlc_interface_rrc*          rlc,
                pdcp_interface_rrc*         pdcp,
                ngap_interface_rrc_nr*      ngap_,
-               gtpu_interface_rrc_nr*      gtpu,
+               enb_bearer_manager&         bearer_mapper_,
                rrc_eutra_interface_rrc_nr* rrc_eutra_);
 
   void stop();
@@ -125,9 +127,9 @@ private:
   mac_interface_rrc_nr*       mac           = nullptr;
   rlc_interface_rrc*          rlc           = nullptr;
   pdcp_interface_rrc*         pdcp          = nullptr;
-  gtpu_interface_rrc_nr*      gtpu      = nullptr;
   ngap_interface_rrc_nr*      ngap          = nullptr;
   rrc_eutra_interface_rrc_nr* rrc_eutra     = nullptr;
+  enb_bearer_manager*         bearer_mapper = nullptr;
 
   // args
   srsran::task_sched_handle task_sched;

srsgnb/src/stack/gnb_stack_nr.cc

@@ -13,6 +13,7 @@
 #include "srsgnb/hdr/stack/gnb_stack_nr.h"
 #include "srsenb/hdr/stack/upper/gtpu.h"
 #include "srsgnb/hdr/stack/ngap/ngap.h"
+#include "srsran/common/bearer_manager.h"
 #include "srsran/common/network_utils.h"
 #include "srsran/common/standard_streams.h"
 #include "srsran/srsran.h"
@@ -20,6 +21,46 @@
 
 namespace srsenb {
 
+class gtpu_pdcp_adapter_nr final : public gtpu_interface_pdcp, public pdcp_interface_gtpu
+{
+public:
+  gtpu_pdcp_adapter_nr(srslog::basic_logger& logger_,
+                       pdcp_interface_gtpu*  pdcp_,
+                       gtpu*                 gtpu_,
+                       enb_bearer_manager&   bearers_) :
+    logger(logger_), pdcp_obj(pdcp_), gtpu_obj(gtpu_), bearers(&bearers_)
+  {}
+
+  /// Converts LCID to EPS-BearerID and sends corresponding PDU to GTPU
+  void write_pdu(uint16_t rnti, uint32_t lcid, srsran::unique_byte_buffer_t pdu) override
+  {
+    auto bearer = bearers->get_lcid_bearer(rnti, lcid);
+    if (not bearer.is_valid()) {
+      logger.error("Bearer rnti=0x%x, lcid=%d not found", rnti, lcid);
+      return;
+    }
+    gtpu_obj->write_pdu(rnti, bearer.eps_bearer_id, std::move(pdu));
+  }
+  void write_sdu(uint16_t rnti, uint32_t eps_bearer_id, srsran::unique_byte_buffer_t sdu, int pdcp_sn = -1) override
+  {
+    auto bearer = bearers->get_radio_bearer(rnti, eps_bearer_id);
+    // route SDU to PDCP entity
+    pdcp_obj->write_sdu(rnti, bearer.lcid, std::move(sdu), pdcp_sn);
+  }
+  std::map<uint32_t, srsran::unique_byte_buffer_t> get_buffered_pdus(uint16_t rnti, uint32_t eps_bearer_id) override
+  {
+    auto bearer = bearers->get_radio_bearer(rnti, eps_bearer_id);
+    // route SDU to PDCP entity
+    return pdcp_obj->get_buffered_pdus(rnti, bearer.lcid);
+  }
+
+private:
+  srslog::basic_logger& logger;
+  gtpu*                 gtpu_obj = nullptr;
+  pdcp_interface_gtpu*  pdcp_obj = nullptr;
+  enb_bearer_manager*   bearers  = nullptr;
+};
+
 gnb_stack_nr::gnb_stack_nr(srslog::sink& log_sink) :
   task_sched{512, 128},
   thread("gNB"),
@@ -33,6 +74,7 @@ gnb_stack_nr::gnb_stack_nr(srslog::sink& log_sink) :
   mac(&task_sched),
   rrc(&task_sched),
   pdcp(&task_sched, pdcp_logger),
+  bearer_manager(new srsenb::enb_bearer_manager()),
   rlc(rlc_logger)
 {
   sync_task_queue    = task_sched.make_task_queue();
@@ -81,6 +123,7 @@ int gnb_stack_nr::init(const gnb_stack_args_t& args_,
     // SA mode
     ngap.reset(new srsenb::ngap(&task_sched, ngap_logger, &srsran::get_rx_io_manager()));
     gtpu.reset(new srsenb::gtpu(&task_sched, gtpu_logger, &srsran::get_rx_io_manager()));
+    gtpu_adapter.reset(new gtpu_pdcp_adapter_nr(gtpu_logger, &pdcp, gtpu.get(), *bearer_manager));
   }
 
   // Init all layers
@@ -90,14 +133,15 @@ int gnb_stack_nr::init(const gnb_stack_args_t& args_,
   }
 
   rlc.init(&pdcp, &rrc, &mac, task_sched.get_timer_handler());
-  pdcp.init(&rlc, &rrc, x2_);
 
-  if (rrc.init(rrc_cfg_, phy, &mac, &rlc, &pdcp, ngap.get(), nullptr, x2_) != SRSRAN_SUCCESS) {
+  if (rrc.init(rrc_cfg_, phy, &mac, &rlc, &pdcp, ngap.get(), *bearer_manager, x2_) != SRSRAN_SUCCESS) {
     stack_logger.error("Couldn't initialize RRC");
     return SRSRAN_ERROR;
   }
 
   if (ngap != nullptr) {
+    pdcp.init(&rlc, &rrc, gtpu_adapter.get());
+
     if (args.ngap_pcap.enable) {
       ngap_pcap.open(args.ngap_pcap.filename.c_str());
       ngap->start_pcap(&ngap_pcap);
@@ -108,7 +152,9 @@ int gnb_stack_nr::init(const gnb_stack_args_t& args_,
     gtpu_args.embms_enable  = false;
     gtpu_args.mme_addr      = args.ngap.amf_addr;
     gtpu_args.gtp_bind_addr = args.ngap.gtp_bind_addr;
-    gtpu->init(gtpu_args, &pdcp);
+    gtpu->init(gtpu_args, gtpu_adapter.get());
+  } else {
+    pdcp.init(&rlc, &rrc, x2_);
   }
 
   // TODO: add SDAP

srsgnb/src/stack/rrc/rrc_nr.cc

@@ -17,6 +17,7 @@
 #include "srsgnb/hdr/stack/rrc/rrc_nr_ue.h"
 #include "srsgnb/src/stack/mac/test/sched_nr_cfg_generators.h"
 #include "srsran/asn1/rrc_nr_utils.h"
+#include "srsran/common/bearer_manager.h"
 #include "srsran/common/common_nr.h"
 #include "srsran/common/phy_cfg_nr_default.h"
 #include "srsran/common/standard_streams.h"
@@ -38,7 +39,7 @@ int rrc_nr::init(const rrc_nr_cfg_t&         cfg_,
                  rlc_interface_rrc*          rlc_,
                  pdcp_interface_rrc*         pdcp_,
                  ngap_interface_rrc_nr*      ngap_,
-                 gtpu_interface_rrc_nr*      gtpu_,
+                 enb_bearer_manager&         bearer_mapper_,
                  rrc_eutra_interface_rrc_nr* rrc_eutra_)
 {
   phy           = phy_;
@@ -46,7 +47,7 @@ int rrc_nr::init(const rrc_nr_cfg_t&         cfg_,
   rlc           = rlc_;
   pdcp          = pdcp_;
   ngap          = ngap_;
-  gtpu      = gtpu_;
+  bearer_mapper = &bearer_mapper_;
   rrc_eutra     = rrc_eutra_;
 
   cfg = cfg_;

srsgnb/src/stack/rrc/rrc_nr_ue.cc

@@ -14,6 +14,7 @@
 #include "srsgnb/hdr/stack/rrc/cell_asn1_config.h"
 #include "srsgnb/hdr/stack/rrc/rrc_nr_config_utils.h"
 #include "srsran/asn1/rrc_nr_utils.h"
+#include "srsran/common/bearer_manager.h"
 #include "srsran/common/string_helpers.h"
 
 using namespace asn1::rrc_nr;
@@ -1180,6 +1181,9 @@ void rrc_nr::ue::establish_eps_bearer(uint32_t pdu_session_id, srsran::const_byt
   next_radio_bearer_cfg.drb_to_add_mod_list_present = true;
   next_radio_bearer_cfg.drb_to_add_mod_list.push_back(drb);
 
+  parent->bearer_mapper->add_eps_bearer(
+      rnti, lcid - 3, srsran::srsran_rat_t::nr, lcid); // TODO: configurable bearer id <-> lcid mapping
+
   logger.info("Established EPS bearer for LCID %u and RNTI 0x%x", lcid, rnti);
 }
 

srsgnb/src/stack/rrc/test/rrc_nr_test.cc

@@ -13,6 +13,7 @@
 #include "rrc_nr_test_helpers.h"
 #include "srsgnb/hdr/stack/rrc/rrc_nr_config_utils.h"
 #include "srsgnb/src/stack/mac/test/sched_nr_cfg_generators.h"
+#include "srsran/common/bearer_manager.h"
 #include "srsran/common/test_common.h"
 #include "srsran/interfaces/gnb_rrc_nr_interfaces.h"
 #include <iostream>
@@ -45,6 +46,7 @@ void test_sib_generation()
   rlc_dummy              rlc_obj;
   pdcp_dummy             pdcp_obj;
   rrc_nr                 rrc_obj(&task_sched);
+  enb_bearer_manager     bearer_mapper;
 
   // set cfg
   rrc_nr_cfg_t rrc_cfg_nr = {};
@@ -59,7 +61,7 @@ void test_sib_generation()
   set_derived_nr_cell_params(rrc_cfg_nr.is_standalone, rrc_cfg_nr.cell_list[0]);
   srsran_assert(check_rrc_nr_cfg_valid(rrc_cfg_nr) == SRSRAN_SUCCESS, "Invalid RRC NR configuration");
 
-  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, nullptr, nullptr, nullptr) ==
+  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, nullptr, bearer_mapper, nullptr) ==
              SRSRAN_SUCCESS);
 
   const sched_nr_interface::cell_cfg_t& nrcell = mac_obj.nr_cells.at(0);
@@ -97,6 +99,7 @@ int test_rrc_setup()
   mac_nr_dummy           mac_obj;
   rlc_dummy              rlc_obj;
   pdcp_dummy             pdcp_obj;
+  enb_bearer_manager     bearer_mapper;
   rrc_nr                 rrc_obj(&task_sched);
 
   // set cfg
@@ -110,7 +113,7 @@ int test_rrc_setup()
   rrc_cfg_nr.is_standalone                         = false;
   set_derived_nr_cell_params(rrc_cfg_nr.is_standalone, rrc_cfg_nr.cell_list[0]);
   srsran_assert(check_rrc_nr_cfg_valid(rrc_cfg_nr) == SRSRAN_SUCCESS, "Invalid RRC NR configuration");
-  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, nullptr, nullptr, nullptr) ==
+  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, nullptr, bearer_mapper, nullptr) ==
              SRSRAN_SUCCESS);
 
   for (uint32_t n = 0; n < 2; ++n) {
@@ -134,6 +137,7 @@ void test_rrc_sa_connection()
   rlc_nr_rrc_tester      rlc_obj;
   pdcp_nr_rrc_tester     pdcp_obj;
   ngap_rrc_tester        ngap_obj;
+  enb_bearer_manager     bearer_mapper;
 
   rrc_nr rrc_obj(&task_sched);
 
@@ -150,7 +154,7 @@ void test_rrc_sa_connection()
   set_derived_nr_cell_params(rrc_cfg_nr.is_standalone, rrc_cfg_nr.cell_list[0]);
   srsran_assert(check_rrc_nr_cfg_valid(rrc_cfg_nr) == SRSRAN_SUCCESS, "Invalid RRC NR configuration");
 
-  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, &ngap_obj, nullptr, nullptr) ==
+  TESTASSERT(rrc_obj.init(rrc_cfg_nr, &phy_obj, &mac_obj, &rlc_obj, &pdcp_obj, &ngap_obj, bearer_mapper, nullptr) ==
              SRSRAN_SUCCESS);
 
   sched_nr_ue_cfg_t uecfg                     = get_default_ue_cfg(1);
@@ -194,6 +198,5 @@ int main(int argc, char** argv)
   TESTASSERT_EQ(0, spy->get_warning_counter());
   TESTASSERT_EQ(0, spy->get_error_counter());
 
-
   return SRSRAN_SUCCESS;
 }