Robert Schmidt
7a298e73cd
This commit repairs the reestablishment after the introduction of the CU UE ID in the CU, different from the DU UE ID. Now, the CU uses an identifier different from the RNTI, used in the MAC, to refer to UEs. To repair the reestablishment, a number of changes needed to be introduced: - Handle old_gNB_DU_UE_id in MAC The MAC handles the old_gNB_DU_UE_id field in the DL RRC Message. The commit adds encoding/decoding of the field. The MAC will drop the old UE, but retain the CellGroup of the corresponding UE(!). Because a UE releases the spCellGroup on reestablishment, the MAC does the same; it needs to reapply the old configuration after a reconfiguration. For the latter, introduce new variables to keep a "future" CellGroupConfig to be applied (reconfigCellGroup) and a flag (expect_reconfiguration) that applies the CellGroupConfig if a DL RRC Message transfer on DCCH, which is assumed to be the reconfiguration. - Add RNTI change in RLC The RLC needs to reuse the old UE context. Hence, we simply change the RNTI in the old context, and delete the new one. - No PDCP UE ID change The previous implementation of the PDCP used the RNTI; hence, the ID needed to be switch (as above for the RLC). Since the PDCP now also uses the CU UE ID, no identifier change is needed, and we remove all corresponding code. - No MAC modifications/update from CU As foreseen by the spec, the CU does not modify or change the cellGroupConfig in the RRC during reestablishment. This change will be generalized in the future to all of the RRC. Also, the nr_rrc_mac_remove_ue() function has been removed: the MAC handles any UE changes autonomeously, without being triggered from the RRC explicitly. - Remove reestablish_rnti_map The RRC does not use RNTIs for UE identification. Hence, a reestablish_rnti_map to link two UEs to each other is not necessary anymore.
348 lines
16 KiB
C
348 lines
16 KiB
C
/*
|
|
* Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership.
|
|
* The OpenAirInterface Software Alliance licenses this file to You under
|
|
* the OAI Public License, Version 1.1 (the "License"); you may not use this file
|
|
* except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.openairinterface.org/?page_id=698
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*-------------------------------------------------------------------------------
|
|
* For more information about the OpenAirInterface (OAI) Software Alliance:
|
|
* contact@openairinterface.org
|
|
*/
|
|
|
|
#include "mac_rrc_dl_handler.h"
|
|
|
|
#include "mac_proto.h"
|
|
#include "openair2/F1AP/f1ap_ids.h"
|
|
#include "openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h"
|
|
#include "openair2/RRC/NR/MESSAGES/asn1_msg.h"
|
|
|
|
#include "uper_decoder.h"
|
|
#include "uper_encoder.h"
|
|
|
|
static NR_RLC_BearerConfig_t *get_bearerconfig_from_srb(const f1ap_srb_to_be_setup_t *srb)
|
|
{
|
|
long priority = srb->srb_id; // high priority for SRB
|
|
e_NR_LogicalChannelConfig__ul_SpecificParameters__bucketSizeDuration bucket =
|
|
NR_LogicalChannelConfig__ul_SpecificParameters__bucketSizeDuration_ms5;
|
|
return get_SRB_RLC_BearerConfig(srb->srb_id, priority, bucket);
|
|
}
|
|
|
|
static int handle_ue_context_srbs_setup(int rnti,
|
|
int srbs_len,
|
|
const f1ap_srb_to_be_setup_t *req_srbs,
|
|
f1ap_srb_to_be_setup_t **resp_srbs,
|
|
NR_CellGroupConfig_t *cellGroupConfig)
|
|
{
|
|
DevAssert(req_srbs != NULL && resp_srbs != NULL && cellGroupConfig != NULL);
|
|
|
|
*resp_srbs = calloc(srbs_len, sizeof(**resp_srbs));
|
|
AssertFatal(*resp_srbs != NULL, "out of memory\n");
|
|
for (int i = 0; i < srbs_len; i++) {
|
|
const f1ap_srb_to_be_setup_t *srb = &req_srbs[i];
|
|
NR_RLC_BearerConfig_t *rlc_BearerConfig = get_bearerconfig_from_srb(srb);
|
|
nr_rlc_add_srb(rnti, srb->srb_id, rlc_BearerConfig);
|
|
|
|
(*resp_srbs)[i] = *srb;
|
|
|
|
int ret = ASN_SEQUENCE_ADD(&cellGroupConfig->rlc_BearerToAddModList->list, rlc_BearerConfig);
|
|
DevAssert(ret == 0);
|
|
}
|
|
return srbs_len;
|
|
}
|
|
|
|
static NR_RLC_BearerConfig_t *get_bearerconfig_from_drb(const f1ap_drb_to_be_setup_t *drb)
|
|
{
|
|
const NR_RLC_Config_PR rlc_conf = drb->rlc_mode == RLC_MODE_UM ? NR_RLC_Config_PR_um_Bi_Directional : NR_RLC_Config_PR_am;
|
|
long priority = 13; // hardcoded for the moment
|
|
return get_DRB_RLC_BearerConfig(3 + drb->drb_id, drb->drb_id, rlc_conf, priority);
|
|
}
|
|
|
|
static int handle_ue_context_drbs_setup(int rnti,
|
|
int drbs_len,
|
|
const f1ap_drb_to_be_setup_t *req_drbs,
|
|
f1ap_drb_to_be_setup_t **resp_drbs,
|
|
NR_CellGroupConfig_t *cellGroupConfig)
|
|
{
|
|
DevAssert(req_drbs != NULL && resp_drbs != NULL && cellGroupConfig != NULL);
|
|
|
|
/* Note: the actual GTP tunnels are created in the F1AP breanch of
|
|
* ue_context_*_response() */
|
|
*resp_drbs = calloc(drbs_len, sizeof(**resp_drbs));
|
|
AssertFatal(*resp_drbs != NULL, "out of memory\n");
|
|
for (int i = 0; i < drbs_len; i++) {
|
|
const f1ap_drb_to_be_setup_t *drb = &req_drbs[i];
|
|
NR_RLC_BearerConfig_t *rlc_BearerConfig = get_bearerconfig_from_drb(drb);
|
|
nr_rlc_add_drb(rnti, drb->drb_id, rlc_BearerConfig);
|
|
|
|
(*resp_drbs)[i] = *drb;
|
|
// just put same number of tunnels in DL as in UL
|
|
(*resp_drbs)[i].up_dl_tnl_length = drb->up_ul_tnl_length;
|
|
|
|
int ret = ASN_SEQUENCE_ADD(&cellGroupConfig->rlc_BearerToAddModList->list, rlc_BearerConfig);
|
|
DevAssert(ret == 0);
|
|
}
|
|
return drbs_len;
|
|
}
|
|
|
|
void ue_context_setup_request(const f1ap_ue_context_setup_t *req)
|
|
{
|
|
gNB_MAC_INST *mac = RC.nrmac[0];
|
|
/* response has same type as request... */
|
|
f1ap_ue_context_setup_t resp = {
|
|
.gNB_CU_ue_id = req->gNB_CU_ue_id,
|
|
.gNB_DU_ue_id = req->gNB_DU_ue_id,
|
|
};
|
|
|
|
if (req->cu_to_du_rrc_information != NULL) {
|
|
AssertFatal(req->cu_to_du_rrc_information->cG_ConfigInfo == NULL, "CG-ConfigInfo not handled\n");
|
|
AssertFatal(req->cu_to_du_rrc_information->uE_CapabilityRAT_ContainerList == NULL, "UE capabilities not handled yet\n");
|
|
AssertFatal(req->cu_to_du_rrc_information->measConfig == NULL, "MeasConfig not handled\n");
|
|
}
|
|
|
|
NR_SCHED_LOCK(&mac->sched_lock);
|
|
|
|
NR_UE_info_t *UE = find_nr_UE(&RC.nrmac[0]->UE_info, req->gNB_DU_ue_id);
|
|
AssertFatal(UE != NULL, "did not find UE with RNTI %04x, but UE Context Setup Failed not implemented\n", req->gNB_DU_ue_id);
|
|
|
|
if (req->srbs_to_be_setup_length > 0) {
|
|
resp.srbs_to_be_setup_length = handle_ue_context_srbs_setup(req->gNB_DU_ue_id,
|
|
req->srbs_to_be_setup_length,
|
|
req->srbs_to_be_setup,
|
|
&resp.srbs_to_be_setup,
|
|
UE->CellGroup);
|
|
}
|
|
|
|
if (req->drbs_to_be_setup_length > 0) {
|
|
resp.drbs_to_be_setup_length = handle_ue_context_drbs_setup(req->gNB_DU_ue_id,
|
|
req->drbs_to_be_setup_length,
|
|
req->drbs_to_be_setup,
|
|
&resp.drbs_to_be_setup,
|
|
UE->CellGroup);
|
|
}
|
|
|
|
if (req->rrc_container != NULL)
|
|
nr_rlc_srb_recv_sdu(req->gNB_DU_ue_id, DCCH, req->rrc_container, req->rrc_container_length);
|
|
|
|
//nr_mac_update_cellgroup()
|
|
resp.du_to_cu_rrc_information = calloc(1, sizeof(du_to_cu_rrc_information_t));
|
|
AssertFatal(resp.du_to_cu_rrc_information != NULL, "out of memory\n");
|
|
resp.du_to_cu_rrc_information->cellGroupConfig = calloc(1,1024);
|
|
AssertFatal(resp.du_to_cu_rrc_information->cellGroupConfig != NULL, "out of memory\n");
|
|
asn_enc_rval_t enc_rval = uper_encode_to_buffer(&asn_DEF_NR_CellGroupConfig,
|
|
NULL,
|
|
UE->CellGroup,
|
|
resp.du_to_cu_rrc_information->cellGroupConfig,
|
|
1024);
|
|
AssertFatal(enc_rval.encoded > 0, "Could not encode CellGroup, failed element %s\n", enc_rval.failed_type->name);
|
|
resp.du_to_cu_rrc_information->cellGroupConfig_length = (enc_rval.encoded + 7) >> 3;
|
|
|
|
/* TODO: need to apply after UE context reconfiguration confirmed? */
|
|
process_CellGroup(UE->CellGroup, UE);
|
|
|
|
NR_SCHED_UNLOCK(&mac->sched_lock);
|
|
|
|
/* some sanity checks, since we use the same type for request and response */
|
|
DevAssert(resp.cu_to_du_rrc_information == NULL);
|
|
DevAssert(resp.du_to_cu_rrc_information != NULL);
|
|
DevAssert(resp.rrc_container == NULL && resp.rrc_container_length == 0);
|
|
|
|
mac->mac_rrc.ue_context_setup_response(req, &resp);
|
|
|
|
/* free the memory we allocated above */
|
|
free(resp.srbs_to_be_setup);
|
|
free(resp.drbs_to_be_setup);
|
|
free(resp.du_to_cu_rrc_information->cellGroupConfig);
|
|
free(resp.du_to_cu_rrc_information);
|
|
}
|
|
|
|
void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
|
|
{
|
|
gNB_MAC_INST *mac = RC.nrmac[0];
|
|
f1ap_ue_context_modif_resp_t resp = {
|
|
.gNB_CU_ue_id = req->gNB_CU_ue_id,
|
|
.gNB_DU_ue_id = req->gNB_DU_ue_id,
|
|
};
|
|
|
|
if (req->cu_to_du_rrc_information != NULL) {
|
|
AssertFatal(req->cu_to_du_rrc_information->cG_ConfigInfo == NULL, "CG-ConfigInfo not handled\n");
|
|
AssertFatal(req->cu_to_du_rrc_information->uE_CapabilityRAT_ContainerList == NULL, "UE capabilities not handled yet\n");
|
|
AssertFatal(req->cu_to_du_rrc_information->measConfig == NULL, "MeasConfig not handled\n");
|
|
}
|
|
|
|
NR_SCHED_LOCK(&mac->sched_lock);
|
|
NR_UE_info_t *UE = find_nr_UE(&RC.nrmac[0]->UE_info, req->gNB_DU_ue_id);
|
|
|
|
if (req->srbs_to_be_setup_length > 0) {
|
|
resp.srbs_to_be_setup_length = handle_ue_context_srbs_setup(req->gNB_DU_ue_id,
|
|
req->srbs_to_be_setup_length,
|
|
req->srbs_to_be_setup,
|
|
&resp.srbs_to_be_setup,
|
|
UE->CellGroup);
|
|
}
|
|
|
|
if (req->drbs_to_be_setup_length > 0) {
|
|
resp.drbs_to_be_setup_length = handle_ue_context_drbs_setup(req->gNB_DU_ue_id,
|
|
req->drbs_to_be_setup_length,
|
|
req->drbs_to_be_setup,
|
|
&resp.drbs_to_be_setup,
|
|
UE->CellGroup);
|
|
}
|
|
|
|
if (req->rrc_container != NULL)
|
|
nr_rlc_srb_recv_sdu(req->gNB_DU_ue_id, DCCH, req->rrc_container, req->rrc_container_length);
|
|
|
|
if (req->ReconfigComplOutcome != RRCreconf_info_not_present && req->ReconfigComplOutcome != RRCreconf_success) {
|
|
LOG_E(NR_MAC,
|
|
"RRC reconfiguration outcome unsuccessful, but no rollback mechanism implemented to come back to old configuration\n");
|
|
}
|
|
|
|
if (req->srbs_to_be_setup_length > 0 || req->drbs_to_be_setup_length > 0) {
|
|
/* TODO: if we change e.g. BWP or MCS table, need to automatically call
|
|
* configure_UE_BWP() (form nr_mac_update_timers()) after some time? */
|
|
|
|
resp.du_to_cu_rrc_information = calloc(1, sizeof(du_to_cu_rrc_information_t));
|
|
AssertFatal(resp.du_to_cu_rrc_information != NULL, "out of memory\n");
|
|
resp.du_to_cu_rrc_information->cellGroupConfig = calloc(1, 1024);
|
|
AssertFatal(resp.du_to_cu_rrc_information->cellGroupConfig != NULL, "out of memory\n");
|
|
asn_enc_rval_t enc_rval = uper_encode_to_buffer(&asn_DEF_NR_CellGroupConfig,
|
|
NULL,
|
|
UE->CellGroup,
|
|
resp.du_to_cu_rrc_information->cellGroupConfig,
|
|
1024);
|
|
AssertFatal(enc_rval.encoded > 0, "Could not encode CellGroup, failed element %s\n", enc_rval.failed_type->name);
|
|
resp.du_to_cu_rrc_information->cellGroupConfig_length = (enc_rval.encoded + 7) >> 3;
|
|
|
|
/* works? */
|
|
nr_mac_update_cellgroup(RC.nrmac[0], req->gNB_DU_ue_id, UE->CellGroup);
|
|
}
|
|
NR_SCHED_UNLOCK(&mac->sched_lock);
|
|
|
|
/* some sanity checks, since we use the same type for request and response */
|
|
DevAssert(resp.cu_to_du_rrc_information == NULL);
|
|
// resp.du_to_cu_rrc_information can be either NULL or not
|
|
DevAssert(resp.rrc_container == NULL && resp.rrc_container_length == 0);
|
|
|
|
mac->mac_rrc.ue_context_modification_response(req, &resp);
|
|
|
|
/* free the memory we allocated above */
|
|
free(resp.srbs_to_be_setup);
|
|
free(resp.drbs_to_be_setup);
|
|
if (resp.du_to_cu_rrc_information != NULL) {
|
|
free(resp.du_to_cu_rrc_information->cellGroupConfig);
|
|
free(resp.du_to_cu_rrc_information);
|
|
}
|
|
}
|
|
|
|
void ue_context_release_command(const f1ap_ue_context_release_cmd_t *cmd)
|
|
{
|
|
/* mark UE as to be deleted after PUSCH failure */
|
|
gNB_MAC_INST *mac = RC.nrmac[0];
|
|
pthread_mutex_lock(&mac->sched_lock);
|
|
NR_UE_info_t *UE = find_nr_UE(&mac->UE_info, cmd->gNB_DU_ue_id);
|
|
if (UE->UE_sched_ctrl.ul_failure || cmd->rrc_container_length == 0) {
|
|
/* The UE is already not connected anymore or we have nothing to forward*/
|
|
nr_rlc_remove_ue(cmd->gNB_DU_ue_id);
|
|
mac_remove_nr_ue(mac, cmd->gNB_DU_ue_id);
|
|
} else {
|
|
/* UE is in sync: forward release message and mark to be deleted
|
|
* after UL failure */
|
|
nr_rlc_srb_recv_sdu(cmd->gNB_DU_ue_id, cmd->srb_id, cmd->rrc_container, cmd->rrc_container_length);
|
|
nr_mac_trigger_release_timer(&UE->UE_sched_ctrl, UE->current_UL_BWP.scs);
|
|
}
|
|
pthread_mutex_unlock(&mac->sched_lock);
|
|
|
|
f1ap_ue_context_release_complete_t complete = {
|
|
.gNB_CU_ue_id = cmd->gNB_CU_ue_id,
|
|
.gNB_DU_ue_id = cmd->gNB_DU_ue_id,
|
|
};
|
|
mac->mac_rrc.ue_context_release_complete(&complete);
|
|
|
|
du_remove_f1_ue_data(cmd->gNB_DU_ue_id);
|
|
}
|
|
|
|
void dl_rrc_message_transfer(const f1ap_dl_rrc_message_t *dl_rrc)
|
|
{
|
|
LOG_D(NR_MAC,
|
|
"DL RRC Message Transfer with %d bytes for RNTI %04x SRB %d\n",
|
|
dl_rrc->rrc_container_length,
|
|
dl_rrc->gNB_DU_ue_id,
|
|
dl_rrc->srb_id);
|
|
|
|
gNB_MAC_INST *mac = RC.nrmac[0];
|
|
pthread_mutex_lock(&mac->sched_lock);
|
|
/* check first that the scheduler knows such UE */
|
|
NR_UE_info_t *UE = find_nr_UE(&mac->UE_info, dl_rrc->gNB_DU_ue_id);
|
|
if (UE == NULL) {
|
|
LOG_E(MAC, "ERROR: unknown UE with RNTI %04x, ignoring DL RRC Message Transfer\n", dl_rrc->gNB_DU_ue_id);
|
|
pthread_mutex_unlock(&mac->sched_lock);
|
|
return;
|
|
}
|
|
pthread_mutex_unlock(&mac->sched_lock);
|
|
|
|
if (!du_exists_f1_ue_data(dl_rrc->gNB_DU_ue_id)) {
|
|
LOG_I(NR_MAC, "No CU UE ID stored for UE RNTI %04x, adding CU UE ID %d\n", dl_rrc->gNB_DU_ue_id, dl_rrc->gNB_CU_ue_id);
|
|
f1_ue_data_t new_ue_data = {.secondary_ue = dl_rrc->gNB_CU_ue_id};
|
|
du_add_f1_ue_data(dl_rrc->gNB_DU_ue_id, &new_ue_data);
|
|
}
|
|
|
|
if (UE->expect_reconfiguration && dl_rrc->srb_id == DCCH) {
|
|
/* we expected a reconfiguration, and this is on DCCH. We assume this is
|
|
* the reconfiguration; nr_mac_update_cellgroup() brings the config into
|
|
* the form expected by nr_mac_update_timers(), and we set the timer to
|
|
* apply the real configuration at expiration.
|
|
* Calling it nr_mac_update_cellgroup() is misleading, and using an
|
|
* intermediate buffer seems not necessary. This is for historical reasons,
|
|
* when we only had pointer to an RRC structure, and wanted to duplicate
|
|
* the contents to be applied later. The actually interesting function here
|
|
* is also configure_UE_BWP(), only called in nr_mac_update_timers().
|
|
* TODO: This should be cleaned up when the whole CellGroupConfig is
|
|
* handled entirely at the DU: no intermediate buffer, trigger the timer
|
|
* from a function (there is nr_mac_enable_ue_rrc_processing_timer(), which
|
|
* is called from the RRC, hence locks the scheduler, which we cannot use). */
|
|
LOG_I(NR_MAC, "triggering rrc_processing_timer time UE %04x\n", UE->rnti);
|
|
pthread_mutex_lock(&mac->sched_lock);
|
|
nr_mac_update_cellgroup(mac, dl_rrc->gNB_DU_ue_id, UE->reconfigCellGroup);
|
|
pthread_mutex_unlock(&mac->sched_lock);
|
|
const uint16_t sl_ahead = mac->if_inst->sl_ahead;
|
|
NR_SubcarrierSpacing_t scs = 1;
|
|
int delay = 10;
|
|
UE->UE_sched_ctrl.rrc_processing_timer = (delay << scs) + sl_ahead;
|
|
}
|
|
|
|
if (dl_rrc->old_gNB_DU_ue_id != NULL) {
|
|
AssertFatal(*dl_rrc->old_gNB_DU_ue_id != dl_rrc->gNB_DU_ue_id,
|
|
"logic bug: current and old gNB DU UE ID cannot be the same\n");
|
|
/* 38.401 says: "Find UE context based on old gNB-DU UE F1AP ID, replace
|
|
* old C-RNTI/PCI with new C-RNTI/PCI". So we delete the new contexts
|
|
* below, then change the C-RNTI of the old one to the new one */
|
|
NR_UE_info_t *oldUE = find_nr_UE(&mac->UE_info, *dl_rrc->old_gNB_DU_ue_id);
|
|
DevAssert(oldUE);
|
|
pthread_mutex_lock(&mac->sched_lock);
|
|
/* 38.331 5.3.7.2 says that the UE releases the spCellConfig, so we drop it
|
|
* from the current configuration. Also, expect the reconfiguration from
|
|
* the CU, so save the old UE's CellGroup for the new UE */
|
|
UE->CellGroup->spCellConfig = NULL;
|
|
nr_mac_update_cellgroup(mac, dl_rrc->gNB_DU_ue_id, UE->CellGroup);
|
|
UE->reconfigCellGroup = oldUE->CellGroup;
|
|
UE->expect_reconfiguration = true;
|
|
oldUE->CellGroup = NULL;
|
|
mac_remove_nr_ue(mac, *dl_rrc->old_gNB_DU_ue_id);
|
|
pthread_mutex_unlock(&mac->sched_lock);
|
|
nr_rlc_remove_ue(dl_rrc->gNB_DU_ue_id);
|
|
nr_rlc_update_rnti(*dl_rrc->old_gNB_DU_ue_id, dl_rrc->gNB_DU_ue_id);
|
|
}
|
|
|
|
/* the DU ue id is the RNTI */
|
|
nr_rlc_srb_recv_sdu(dl_rrc->gNB_DU_ue_id, dl_rrc->srb_id, dl_rrc->rrc_container, dl_rrc->rrc_container_length);
|
|
}
|