osmo-pcu/src/llc.h

153 lines
4.4 KiB
C

/* 3GPP TS 44.064
* Copyright (C) 2013 by Holger Hans Peter Freyther
* Copyright (C) 2022 by by Sysmocom s.f.m.c. GmbH
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#pragma once
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <osmocom/core/endian.h>
#include <osmocom/core/linuxlist.h>
#include <osmocom/core/msgb.h>
#include <osmocom/core/endian.h>
#include "gprs_codel.h"
#define LLC_MAX_LEN 1543
struct gprs_rlcmac_bts;
struct GprsMs;
struct gprs_llc_hdr {
#if OSMO_IS_LITTLE_ENDIAN
union { /* 5.2, 6.2.0 */
uint8_t address;
uint8_t sapi:4, unused:2, c_r:1, pd:1;
#elif OSMO_IS_BIG_ENDIAN
/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianess.py) */
union {
uint8_t address;
uint8_t pd:1, c_r:1, unused:2, sapi:4;
#endif
};
uint8_t control[0];
} __attribute__ ((packed));
/**
* I represent the LLC data to a MS
*/
struct gprs_llc {
uint8_t frame[LLC_MAX_LEN]; /* current DL or UL frame */
uint16_t index; /* current write/read position of frame */
uint16_t length; /* len of current DL LLC_frame, 0 == no frame */
};
bool llc_is_user_data_frame(const uint8_t *data, size_t len);
void llc_init(struct gprs_llc *llc);
void llc_reset(struct gprs_llc *llc);
void llc_reset_frame_space(struct gprs_llc *llc);
void llc_put_frame(struct gprs_llc *llc, const uint8_t *data, size_t len);
void llc_put_dummy_frame(struct gprs_llc *llc, size_t req_len);
void llc_append_frame(struct gprs_llc *llc, const uint8_t *data, size_t len);
static inline uint16_t llc_chunk_size(const struct gprs_llc *llc)
{
return llc->length - llc->index;
}
static inline uint16_t llc_remaining_space(const struct gprs_llc *llc)
{
return LLC_MAX_LEN - llc->length;
}
static inline uint16_t llc_frame_length(const struct gprs_llc *llc)
{
return llc->length;
}
static inline void llc_consume(struct gprs_llc *llc, size_t len)
{
llc->index += len;
}
static inline void llc_consume_data(struct gprs_llc *llc, uint8_t *data, size_t len)
{
/* copy and increment index */
memcpy(data, llc->frame + llc->index, len);
llc_consume(llc, len);
}
static inline bool llc_fits_in_current_frame(const struct gprs_llc *llc, uint8_t chunk_size)
{
return llc->length + chunk_size <= LLC_MAX_LEN;
}
struct MetaInfo {
struct timespec recv_time;
struct timespec expire_time;
};
/**
* I store the LLC frames that come from the SGSN.
*/
enum gprs_llc_queue_prio { /* lowest value has highest prio */
LLC_QUEUE_PRIO_GMM = 0, /* SAPI 1 */
LLC_QUEUE_PRIO_TOM_SMS, /* SAPI 2,7,8 */
LLC_QUEUE_PRIO_OTHER, /* Other SAPIs */
_LLC_QUEUE_PRIO_SIZE /* used to calculate size of enum */
};
struct gprs_llc_prio_queue {
struct gprs_codel codel_state;
struct llist_head queue; /* queued LLC DL data. See enum gprs_llc_queue_prio. */
};
struct gprs_llc_queue {
struct GprsMs *ms; /* backpointer */
uint32_t avg_queue_delay; /* Average delay of data going through the queue */
size_t queue_size;
size_t queue_octets;
bool use_codel;
struct gprs_llc_prio_queue pq[_LLC_QUEUE_PRIO_SIZE]; /* queued LLC DL data. See enum gprs_llc_queue_prio. */
};
void llc_queue_calc_pdu_lifetime(struct gprs_rlcmac_bts *bts, const uint16_t pdu_delay_csec,
struct timespec *tv);
bool llc_queue_is_frame_expired(const struct timespec *tv_now, const struct timespec *tv);
void llc_queue_init(struct gprs_llc_queue *q, struct GprsMs *ms);
void llc_queue_clear(struct gprs_llc_queue *q, struct gprs_rlcmac_bts *bts);
void llc_queue_set_codel_interval(struct gprs_llc_queue *q, unsigned int interval);
void llc_queue_move_and_merge(struct gprs_llc_queue *q, struct gprs_llc_queue *o);
void llc_queue_enqueue(struct gprs_llc_queue *q, struct msgb *llc_msg, const struct timespec *expire_time);
struct msgb *llc_queue_dequeue(struct gprs_llc_queue *q);
static inline size_t llc_queue_size(const struct gprs_llc_queue *q)
{
return q->queue_size;
}
static inline size_t llc_queue_octets(const struct gprs_llc_queue *q)
{
return q->queue_octets;
}
#ifdef __cplusplus
}
#endif