LAPDm: Allow sending unit data on DCCH
It is used to transfer PHYSICAL INFORMATION message to the MS.
diff --git a/src/gsm/lapdm.c b/src/gsm/lapdm.c
index 71045aa..52290cb 100644
--- a/src/gsm/lapdm.c
+++ b/src/gsm/lapdm.c
@@ -407,6 +407,11 @@
switch (OSMO_PRIM_HDR(&dp->oph)) {
case OSMO_PRIM(PRIM_DL_EST, PRIM_OP_INDICATION):
+ if (dp->oph.msg && dp->oph.msg->len == 0) {
+ /* omit L3 info by freeing message */
+ msgb_free(dp->oph.msg);
+ dp->oph.msg = NULL;
+ }
rll_msg = RSL_MT_EST_IND;
break;
case OSMO_PRIM(PRIM_DL_EST, PRIM_OP_CONFIRM):
@@ -817,10 +822,10 @@
static int rslms_rx_rll_udata_req(struct msgb *msg, struct lapdm_datalink *dl)
{
struct lapdm_entity *le = dl->entity;
- int ui_bts = (le->mode == LAPDM_MODE_BTS);
struct abis_rsl_rll_hdr *rllh = msgb_l2(msg);
uint8_t chan_nr = rllh->chan_nr;
uint8_t link_id = rllh->link_id;
+ int ui_bts = (le->mode == LAPDM_MODE_BTS && (link_id & 0x40));
uint8_t sapi = link_id & 7;
struct tlv_parsed tv;
int length;
@@ -844,9 +849,10 @@
msg->l3h = (uint8_t *) TLVP_VAL(&tv, RSL_IE_L3_INFO);
length = TLVP_LEN(&tv, RSL_IE_L3_INFO);
/* check if the layer3 message length exceeds N201 */
- if (length + 4 + !ui_bts > 23) {
+ if (length + ((link_id & 0x40) ? 4 : 2) + !ui_bts > 23) {
LOGP(DLLAPD, LOGL_ERROR, "frame too large: %d > N201(%d) "
- "(discarding)\n", length, 18 + ui_bts);
+ "(discarding)\n", length,
+ ((link_id & 0x40) ? 18 : 20) + ui_bts);
msgb_free(msg);
return -EIO;
}
@@ -860,13 +866,16 @@
msg->tail = msg->l3h + length;
/* Push L1 + LAPDm header on msgb */
- msg->l2h = msgb_push(msg, 4 + !ui_bts);
- msg->l2h[0] = le->tx_power;
- msg->l2h[1] = le->ta;
- msg->l2h[2] = LAPDm_ADDR(LAPDm_LPD_NORMAL, sapi, dl->dl.cr.loc2rem.cmd);
- msg->l2h[3] = LAPDm_CTRL_U(LAPDm_U_UI, 0);
+ msg->l2h = msgb_push(msg, 2 + !ui_bts);
+ msg->l2h[0] = LAPDm_ADDR(LAPDm_LPD_NORMAL, sapi, dl->dl.cr.loc2rem.cmd);
+ msg->l2h[1] = LAPDm_CTRL_U(LAPDm_U_UI, 0);
if (!ui_bts)
- msg->l2h[4] = LAPDm_LEN(length);
+ msg->l2h[2] = LAPDm_LEN(length);
+ if (link_id & 0x40) {
+ msg->l2h = msgb_push(msg, 2);
+ msg->l2h[0] = le->tx_power;
+ msg->l2h[1] = le->ta;
+ }
/* Tramsmit */
return tx_ph_data_enqueue(dl, msg, chan_nr, link_id, 23);
@@ -1083,7 +1092,6 @@
}
switch (msg_type) {
- case RSL_MT_UNIT_DATA_REQ:
case RSL_MT_DATA_REQ:
case RSL_MT_SUSP_REQ:
case RSL_MT_REL_REQ: