diff options
Diffstat (limited to 'src/gprs_rlcmac_data.cpp')
| -rw-r--r-- | src/gprs_rlcmac_data.cpp | 1106 |
1 files changed, 1000 insertions, 106 deletions
diff --git a/src/gprs_rlcmac_data.cpp b/src/gprs_rlcmac_data.cpp index ce90c47..018ef3e 100644 --- a/src/gprs_rlcmac_data.cpp +++ b/src/gprs_rlcmac_data.cpp @@ -20,13 +20,17 @@ #include <gprs_bssgp_pcu.h> #include <gprs_rlcmac.h> +#include <pcu_l1_if.h> /* After receiving these framess, we send ack/nack. */ #define ACK_AFTER_FRAMES 20 +/* If acknowledgement to uplink/downlin assignmentshould be polled */ +#define POLLING_ASSIGNMENT 0 + extern "C" { /* TS 04.60 10.2.2 */ -struct rlc_dl_header { +struct rlc_ul_header { uint8_t r:1, si:1, cv:4, @@ -39,6 +43,18 @@ struct rlc_dl_header { bsn:7; } __attribute__ ((packed)); +struct rlc_dl_header { + uint8_t usf:3, + s_p:1, + rrbp:2, + pt:2; + uint8_t fbi:1, + tfi:5, + pr:2; + uint8_t e:1, + bsn:7; +} __attribute__ ((packed)); + struct rlc_li_field { uint8_t e:1, m:1, @@ -46,10 +62,249 @@ struct rlc_li_field { } __attribute__ ((packed)); } +int gprs_rlcmac_poll_timeout(struct gprs_rlcmac_tbf *tbf) +{ + LOGP(DRLCMAC, LOGL_NOTICE, "Poll timeout for TBF=%d\n", tbf->tfi); + + tbf->poll_state = GPRS_RLCMAC_POLL_NONE; + + if (tbf->ul_ack_state == GPRS_RLCMAC_UL_ACK_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_DEBUG, "- Timeout for polling PACKET " + "CONTROL ACK for PACKET UPLINK ACK\n"); + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_NONE; + if (tbf->state == GPRS_RLCMAC_FINISHED) { + tbf->dir.ul.n3103++; + if (tbf->dir.ul.n3103 == N3103_MAX) { + LOGP(DRLCMAC, LOGL_DEBUG, "- N3103 exceeded\n"); + tbf_new_state(tbf, GPRS_RLCMAC_RELEASING); + tbf_timer_start(tbf, 3169, T3169); + return 0; + } + /* reschedule UL ack */ + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_SEND_ACK; + } + } else + if (tbf->ul_ass_state == GPRS_RLCMAC_UL_ASS_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_DEBUG, "- Timeout for polling PACKET " + "CONTROL ACK for PACKET UPLINK ASSIGNMENT.\n"); + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; + } else + if (tbf->dl_ass_state == GPRS_RLCMAC_DL_ASS_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_DEBUG, "- Timeout for polling PACKET " + "CONTROL ACK for PACKET DOWNLINK ASSIGNMENT.\n"); + tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; + /* in case out downlink assigment failed: */ + if (tbf->state == GPRS_RLCMAC_ASSIGN) { + LOGP(DRLCMAC, LOGL_DEBUG, "- Assignment failed\n"); + tbf_free(tbf); + } + } else + if (tbf->direction == GPRS_RLCMAC_DL_TBF) + { + LOGP(DRLCMAC, LOGL_DEBUG, "- Timeout for polling PACKET " + " DOWNLINK ACK.\n"); + tbf->dir.dl.n3105++; + if (tbf->dir.dl.n3105 == N3105_MAX) { + LOGP(DRLCMAC, LOGL_DEBUG, "- N3105 exceeded\n"); + tbf_new_state(tbf, GPRS_RLCMAC_RELEASING); + tbf_timer_start(tbf, 3195, T3195); + return 0; + } + } + + return 0; +} + +/* Received Uplink RLC control block. */ +int gprs_rlcmac_rcv_control_block(bitvec *rlc_block, uint32_t fn) +{ + uint8_t tfi = 0; + uint32_t tlli = 0; + struct gprs_rlcmac_tbf *tbf; + + RlcMacUplink_t * ul_control_block = (RlcMacUplink_t *)malloc(sizeof(RlcMacUplink_t)); + LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ RX : Uplink Control Block +++++++++++++++++++++++++\n"); + decode_gsm_rlcmac_uplink(rlc_block, ul_control_block); + LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); + LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- RX : Uplink Control Block -------------------------\n"); + switch (ul_control_block->u.MESSAGE_TYPE) { + case MT_PACKET_CONTROL_ACK: + tlli = ul_control_block->u.Packet_Control_Acknowledgement.TLLI; + tbf = tbf_by_poll_fn(fn); + if (!tbf) { + LOGP(DRLCMAC, LOGL_NOTICE, "PACKET CONTROL ACK with " + "unknown FN=%u TLL=0x%08x\n", fn, tlli); + break; + } + tfi = tbf->tfi; + if (tlli != tbf->tlli) { + LOGP(DRLCMAC, LOGL_NOTICE, "Phone changed TLLI to " + "0x%08x\n", tlli); + tbf->tlli = tlli; + } + LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u TLLI: 0x%08x Packet Control Ack\n", tbf->tfi, tbf->tlli); + tbf->poll_state = GPRS_RLCMAC_POLL_NONE; + + /* check if this control ack belongs to packet uplink ack */ + if (tbf->ul_ack_state == GPRS_RLCMAC_UL_ACK_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] END TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_NONE; + tbf_free(tbf); + break; + } + if (tbf->dl_ass_state == GPRS_RLCMAC_DL_ASS_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] DOWNLINK ASSIGNED TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); + tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; + break; + } + if (tbf->ul_ass_state == GPRS_RLCMAC_UL_ASS_WAIT_ACK) { + LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [DOWNLINK] UPLINK ASSIGNED TFI: %u TLLI: 0x%08x \n", tbf->tfi, tbf->tlli); + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; + break; + } + LOGP(DRLCMAC, LOGL_ERROR, "Error: received PACET CONTROL ACK " + "at no request\n"); + break; + case MT_PACKET_DOWNLINK_ACK_NACK: + tfi = ul_control_block->u.Packet_Downlink_Ack_Nack.DOWNLINK_TFI; + tbf = tbf_by_poll_fn(fn); + if (!tbf) { + LOGP(DRLCMAC, LOGL_NOTICE, "PACKET DOWNLINK ACK with " + "unknown FN=%u TFI=%d\n", fn, tfi); + break; + } + /* reset N3105 */ + tbf->dir.dl.n3105 = 0; + /* stop timer T3191 */ + tbf_timer_stop(tbf); + tlli = tbf->tlli; + LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u TLLI: 0x%08x Packet Downlink Ack/Nack\n", tbf->tfi, tbf->tlli); + tbf->poll_state = GPRS_RLCMAC_POLL_NONE; + + gprs_rlcmac_downlink_ack(tbf, + ul_control_block->u.Packet_Downlink_Ack_Nack.Ack_Nack_Description.FINAL_ACK_INDICATION, + ul_control_block->u.Packet_Downlink_Ack_Nack.Ack_Nack_Description.STARTING_SEQUENCE_NUMBER, + ul_control_block->u.Packet_Downlink_Ack_Nack.Ack_Nack_Description.RECEIVED_BLOCK_BITMAP); + /* check for channel request */ + if (ul_control_block->u.Packet_Downlink_Ack_Nack.Exist_Channel_Request_Description) { + uint8_t trx, ts, usf; + struct gprs_rlcmac_tbf *ul_tbf; + + LOGP(DRLCMAC, LOGL_DEBUG, "MS requests UL TBF in ack " + "message, so we provide one:\n"); +uplink_request: + /* create new tbf */ + tfi = tfi_alloc(&trx, &ts); + if (tfi < 0) { + LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource\n"); + /* FIXME: send reject */ + break; + } + usf = find_free_usf(trx, ts); + if (usf < 0) { + LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource for USF\n"); + /* FIXME: send reject */ + break; + } + ul_tbf = tbf_alloc(tfi, trx, ts); + ul_tbf->tlli = tbf->tlli; + ul_tbf->tlli_valid = 1; /* no content resolution */ + ul_tbf->ta = tbf->ta; /* use current TA */ + ul_tbf->direction = GPRS_RLCMAC_UL_TBF; + ul_tbf->dir.ul.usf = usf; + tbf_new_state(ul_tbf, GPRS_RLCMAC_FLOW); + tbf_timer_start(ul_tbf, 3169, T3169); + LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] START TFI: %u\n", ul_tbf->tfi); + /* schedule uplink assignment */ + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_SEND_ASS; + } + break; + case MT_PACKET_RESOURCE_REQUEST: + if (ul_control_block->u.Packet_Resource_Request.ID.UnionType) { + tlli = ul_control_block->u.Packet_Resource_Request.ID.u.TLLI; + tbf = tbf_by_tlli(tlli, GPRS_RLCMAC_UL_TBF); + if (!tbf) { + LOGP(DRLCMAC, LOGL_NOTICE, "PACKET RESSOURCE REQ unknown uplink TLLI=0x%08x\n", tlli); + break; + } + tfi = tbf->tfi; + } else { + if (ul_control_block->u.Packet_Resource_Request.ID.u.Global_TFI.UnionType) { + tfi = ul_control_block->u.Packet_Resource_Request.ID.u.Global_TFI.u.DOWNLINK_TFI; + tbf = tbf_by_tfi(tfi, GPRS_RLCMAC_DL_TBF); + if (!tbf) { + LOGP(DRLCMAC, LOGL_NOTICE, "PACKET RESSOURCE REQ unknown downlink TFI=%d\n", tlli); + break; + } + } else { + tfi = ul_control_block->u.Packet_Resource_Request.ID.u.Global_TFI.u.UPLINK_TFI; + tbf = tbf_by_tfi(tfi, GPRS_RLCMAC_UL_TBF); + if (!tbf) { + LOGP(DRLCMAC, LOGL_NOTICE, "PACKET RESSOURCE REQ unknown uplink TFI=%d\n", tlli); + break; + } + } + tlli = tbf->tlli; + } + LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u TLLI: 0x%08x Packet ressource request\n", tbf->tfi, tbf->tlli); +#warning FIXME +puts("FIXME: UL request during UL request"); exit(0); + + + break; + default: + LOGP(DRLCMAC, LOGL_ERROR, "RX: [PCU <- BTS] unknown control block received\n"); + } + free(ul_control_block); + return 1; +} + + +void tbf_timer_cb(void *_tbf) +{ + struct gprs_rlcmac_tbf *tbf = (struct gprs_rlcmac_tbf *)_tbf; + + LOGP(DRLCMAC, LOGL_DEBUG, "TBF=%d timer %u expired.\n", tbf->tfi, + tbf->T); + + tbf->num_T_exp++; + + switch (tbf->T) { +#ifdef DEBUG_DL_ASS_IDLE + case 1234: + gprs_rlcmac_trigger_downlink_assignment(tbf, 0); + break; +#endif + case 0: /* assignment */ + /* change state to FLOW, so scheduler will start transmission */ + if (tbf->state == GPRS_RLCMAC_ASSIGN) + tbf_new_state(tbf, GPRS_RLCMAC_FLOW); + else + LOGP(DRLCMAC, LOGL_ERROR, "Error: TBF is not in assign " + "state\n"); + break; + case 3169: + case 3191: + case 3193: + case 3195: + LOGP(DRLCMAC, LOGL_DEBUG, "TBF will be freed due to timeout\n"); + /* free TBF */ + tbf_free(tbf); + break; + default: + LOGP(DRLCMAC, LOGL_ERROR, "Timer expired in unknown mode: %u\n", + tbf->T); + } +} + +/* + * UL data block flow + */ + /* get TLLI from received UL data block */ static int tlli_from_ul_data(uint8_t *data, uint8_t len, uint32_t *tlli) { - struct rlc_dl_header *rh = (struct rlc_dl_header *)data; + struct rlc_ul_header *rh = (struct rlc_ul_header *)data; struct rlc_li_field *li; uint8_t e; @@ -62,7 +317,7 @@ static int tlli_from_ul_data(uint8_t *data, uint8_t len, uint32_t *tlli) /* if E is not set (LI follows) */ while (!e) { if (!len) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA LI extended, " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA LI extended, " "but no more data\n"); return -EINVAL; } @@ -76,7 +331,7 @@ static int tlli_from_ul_data(uint8_t *data, uint8_t len, uint32_t *tlli) len--; } if (len < 4) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA TLLI out of frame " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TLLI out of frame " "border\n"); return -EINVAL; } @@ -90,13 +345,13 @@ static int tlli_from_ul_data(uint8_t *data, uint8_t len, uint32_t *tlli) static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, uint8_t len) { - struct rlc_dl_header *rh = (struct rlc_dl_header *)data; + struct rlc_ul_header *rh = (struct rlc_ul_header *)data; uint8_t e, m; struct rlc_li_field *li; uint8_t frame_offset[16], offset = 0, chunk; int i, frames = 0; - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Assembling frames: (len=%d)\n", len); + LOGP(DRLCMACUL, LOGL_DEBUG, "- Assembling frames: (len=%d)\n", len); data += 3; len -= 3; @@ -106,18 +361,18 @@ static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, /* Parse frame offsets from length indicator(s), if any. */ while (1) { if (frames == (int)sizeof(frame_offset)) { - LOGP(DRLCMACDATA, LOGL_ERROR, "Too many frames in " + LOGP(DRLCMACUL, LOGL_ERROR, "Too many frames in " "block\n"); return -EINVAL; } frame_offset[frames++] = offset; - LOGP(DRLCMACDATA, LOGL_DEBUG, "-- Frame %d starts at offset " + LOGP(DRLCMACUL, LOGL_DEBUG, "-- Frame %d starts at offset " "%d\n", frames, offset); if (!len) break; /* M == 0 and E == 0 is not allowed in this version. */ if (!m && !e) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA TFI=%d " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TFI=%d " "ignored, because M='0' and E='0'.\n", tbf->tfi); return 0; @@ -129,6 +384,8 @@ static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, /* There is a new frame and an LI that delimits it. */ if (m) { li = (struct rlc_li_field *)data; + LOGP(DRLCMACUL, LOGL_DEBUG, "-- Delimiter len=%d\n", + li->li); /* Special case: LI == 0 * If the last segment would fit precisely into the * rest of the RLC MAC block, there would be no way @@ -153,16 +410,37 @@ static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, } } if (!m) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Last frame carries spare " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Last frame carries spare " "data\n"); } - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Data length after length fields: %d\n", + LOGP(DRLCMACUL, LOGL_DEBUG, "- Data length after length fields: %d\n", len); + /* TLLI */ if (rh->ti) { + if (len < 4) { + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TLLI out of " + "frame border\n"); + return -EINVAL; + } data += 4; len -= 4; - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Length after skipping TLLI: " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Length after skipping TLLI: " + "%d\n", len); + } + + /* PFI */ + if (rh->pi) { + LOGP(DRLCMACUL, LOGL_ERROR, "ERROR: PFI not supported, " + "please disable in SYSTEM INFORMATION\n"); + if (len < 1) { + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA PFI out of " + "frame border\n"); + return -EINVAL; + } + data++; + len--; + LOGP(DRLCMACUL, LOGL_DEBUG, "- Length after skipping PFI: " "%d\n", len); } @@ -174,7 +452,7 @@ static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, /* Check if last offset would exceed frame. */ if (offset > len) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA TFI=%d ignored, " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TFI=%d ignored, " "because LI exceeds frame length.\n", tbf->tfi); return -EINVAL; } @@ -192,91 +470,55 @@ static int gprs_rlcmac_assemble_llc(struct gprs_rlcmac_tbf *tbf, uint8_t *data, /* data until next frame */ chunk = frame_offset[i + 1] - frame_offset[i]; } - LOGP(DRLCMACDATA, LOGL_DEBUG, "-- Appending chunk (len=%d) to " + LOGP(DRLCMACUL, LOGL_DEBUG, "-- Appending chunk (len=%d) to " "frame at %d.\n", chunk, tbf->llc_index); if (tbf->llc_index + chunk > LLC_MAX_LEN) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "LLC frame exceeds " + LOGP(DRLCMACUL, LOGL_NOTICE, "LLC frame exceeds " "maximum size.\n"); chunk = LLC_MAX_LEN - tbf->llc_index; } memcpy(tbf->llc_frame + tbf->llc_index, data + frame_offset[i], chunk); tbf->llc_index += chunk; - /* not last frame ? */ + /* not last frame. */ if (i != frames - 1) { /* send frame to SGSN */ - LOGP(DRLCMACDATA, LOGL_INFO, "Complete UL frame for " + LOGP(DRLCMACUL, LOGL_INFO, "Complete UL frame for " "TFI=%d: %s\n", tbf->tfi, osmo_hexdump(tbf->llc_frame, tbf->llc_index)); gprs_rlcmac_tx_ul_ud(tbf); - tbf->llc_index = 0; + tbf->llc_index = 0; /* reset frame space */ + /* also check if CV==0, because the frame may fill up the + * block precisely, then it is also complete. normally the + * frame would be extended into the next block with a 0-length + * delimiter added to this block. */ + } else if (rh->cv == 0) { + /* send frame to SGSN */ + LOGP(DRLCMACUL, LOGL_INFO, "Complete UL frame for " + "TFI=%d that fits precisely in last block: " + "%s\n", tbf->tfi, + osmo_hexdump(tbf->llc_frame, tbf->llc_index)); + gprs_rlcmac_tx_ul_ud(tbf); + tbf->llc_index = 0; /* reset frame space */ } } return 0; } -/* * generate uplink ack - */ -void write_packet_uplink_ack(bitvec * dest, struct gprs_rlcmac_tbf *tbf, - uint8_t final) -{ - // TODO We should use our implementation of encode RLC/MAC Control messages. - unsigned wp = 0; - uint16_t i, bbn; - uint16_t mod_sns_half = (tbf->sns >> 1) - 1; - char bit; - - LOGP(DRLCMACDATA, LOGL_DEBUG, "Sending Ack/Nack for TBF=%d " - "(final=%d)\n", tbf->tfi, final); - - bitvec_write_field(dest, wp,0x1,2); // payload - bitvec_write_field(dest, wp,0x0,2); // Uplink block with TDMA framenumber (N+13) - bitvec_write_field(dest, wp,final,1); // Suppl/Polling Bit - bitvec_write_field(dest, wp,0x0,3); // Uplink state flag - - //bitvec_write_field(dest, wp,0x0,1); // Reduced block sequence number - //bitvec_write_field(dest, wp,BSN+6,5); // Radio transaction identifier - //bitvec_write_field(dest, wp,0x1,1); // Final segment - //bitvec_write_field(dest, wp,0x1,1); // Address control - - //bitvec_write_field(dest, wp,0x0,2); // Power reduction: 0 - //bitvec_write_field(dest, wp,TFI,5); // Temporary flow identifier - //bitvec_write_field(dest, wp,0x1,1); // Direction - - bitvec_write_field(dest, wp,0x09,6); // MESSAGE TYPE - bitvec_write_field(dest, wp,0x0,2); // Page Mode - - bitvec_write_field(dest, wp,0x0,2); - bitvec_write_field(dest, wp,tbf->tfi,5); // Uplink TFI - bitvec_write_field(dest, wp,0x0,1); - - bitvec_write_field(dest, wp,0x0,2); // CS1 - bitvec_write_field(dest, wp,final,1); // FINAL_ACK_INDICATION - bitvec_write_field(dest, wp,tbf->dir.ul.v_r,7); // STARTING_SEQUENCE_NUMBER - // RECEIVE_BLOCK_BITMAP - LOGP(DRLCMACDATA, LOGL_DEBUG, "- ack bitmap: \""); - for (i = 0, bbn = (tbf->dir.ul.v_r - 1) & mod_sns_half; i < 64; - i++, bbn = (bbn - 1) & mod_sns_half) { - bit = tbf->dir.ul.v_n[bbn]; - if (bit == 0) - bit = ' '; - LOGPC(DRLCMACDATA, LOGL_DEBUG, "%c", bit); - bitvec_write_field(dest, wp,(bit == 'R'),1); - } - LOGPC(DRLCMACDATA, LOGL_DEBUG, "\"\n"); - bitvec_write_field(dest, wp,0x1,1); // CONTENTION_RESOLUTION_TLLI = present - bitvec_write_field(dest, wp,tbf->tlli,8*4); - bitvec_write_field(dest, wp,0x00,4); //spare - bitvec_write_field(dest, wp,0x5,4); //0101 -} - struct msgb *gprs_rlcmac_send_uplink_ack(struct gprs_rlcmac_tbf *tbf, uint32_t fn) { int final = (tbf->state == GPRS_RLCMAC_FINISHED); struct msgb *msg; + if (final && tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { + LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " + "sheduled for TBF=%d, so we must wait for final uplink " + "ack...\n", tbf->tfi); + return NULL; + } + msg = msgb_alloc(23, "rlcmac_ul_ack"); if (!msg) return NULL; @@ -292,14 +534,12 @@ struct msgb *gprs_rlcmac_send_uplink_ack(struct gprs_rlcmac_tbf *tbf, bitvec_free(ack_vec); if (final) { - if (tbf->poll_state == GPRS_RLCMAC_POLL_SCHED) - LOGP(DRLCMACDATA, LOGL_ERROR, "Polling is already " - "sheduled for TBF=%d\n", tbf->tfi); tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; tbf->poll_fn = (fn + 13) % 2715648; - tbf->dir.ul.substate = GPRS_RLCMAC_UL_WAIT_POLL; + /* waiting for final acknowledge */ + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_WAIT_ACK; } else - tbf->dir.ul.substate = GPRS_RLCMAC_UL_NONE; + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_NONE; return msg; } @@ -311,61 +551,61 @@ struct msgb *gprs_rlcmac_send_uplink_ack(struct gprs_rlcmac_tbf *tbf, int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) { struct gprs_rlcmac_tbf *tbf; - struct rlc_dl_header *rh = (struct rlc_dl_header *)data; + struct rlc_ul_header *rh = (struct rlc_ul_header *)data; uint16_t mod_sns, mod_sns_half, offset_v_q, offset_v_r, index; int rc; if (len < 23) { - LOGP(DRLCMACDATA, LOGL_ERROR, "Dropping short frame " + LOGP(DRLCMACUL, LOGL_ERROR, "Dropping short frame " "(len = %d)\n", len); return -EINVAL; } /* find TBF inst from given TFI */ - tbf = tbf_by_tfi(rh->tfi); + tbf = tbf_by_tfi(rh->tfi, GPRS_RLCMAC_UL_TBF); if (!tbf) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA unknown TFI=%d\n", + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA unknown TFI=%d\n", rh->tfi); return 0; } if (tbf->direction != GPRS_RLCMAC_UL_TBF) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA TFI=%d not Uplink " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TFI=%d not Uplink " "tbf\n", rh->tfi); return 0; } - LOGP(DRLCMACDATA, LOGL_INFO, "UL DATA TFI=%d received (V(Q)=%d .. " + LOGP(DRLCMACUL, LOGL_INFO, "UL DATA TFI=%d received (V(Q)=%d .. " "V(R)=%d)\n", rh->tfi, tbf->dir.ul.v_q, tbf->dir.ul.v_r); /* get TLLI */ if (!tbf->tlli_valid) { /* no TLLI yet */ if (!rh->ti) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "UL DATA TFI=%d without " + LOGP(DRLCMACUL, LOGL_NOTICE, "UL DATA TFI=%d without " "TLLI, but no TLLI received yet\n", rh->tfi); return 0; } rc = tlli_from_ul_data(data, len, &tbf->tlli); if (rc) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "Failed to decode TLLI " + LOGP(DRLCMACUL, LOGL_NOTICE, "Failed to decode TLLI " "of UL DATA TFI=%d.\n", rh->tfi); return 0; } tbf->tlli_valid = 1; - LOGP(DRLCMACDATA, LOGL_DEBUG, " Decoded premier TLLI=0x%08x of " + LOGP(DRLCMACUL, LOGL_DEBUG, " Decoded premier TLLI=0x%08x of " "UL DATA TFI=%d.\n", tbf->tlli, rh->tfi); /* already have TLLI, but we stille get another one */ } else if (rh->ti) { uint32_t tlli; rc = tlli_from_ul_data(data, len, &tlli); if (rc) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "Failed to decode TLLI " + LOGP(DRLCMACUL, LOGL_NOTICE, "Failed to decode TLLI " "of UL DATA TFI=%d.\n", rh->tfi); return 0; } if (tlli != tbf->tlli) { - LOGP(DRLCMACDATA, LOGL_NOTICE, "TLLI mismatch on UL " + LOGP(DRLCMACUL, LOGL_NOTICE, "TLLI mismatch on UL " "DATA TFI=%d. (Ignoring due to contention " "resolution)\n", rh->tfi); return 0; @@ -386,7 +626,7 @@ int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) /* If out of window (may happen if blocks below V(Q) are received * again. */ if (offset_v_q >= tbf->ws) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- BSN %d out of window " + LOGP(DRLCMACUL, LOGL_DEBUG, "- BSN %d out of window " "%d..%d (it's normal)\n", rh->bsn, tbf->dir.ul.v_q, (tbf->dir.ul.v_q + tbf->ws - 1) & mod_sns); return 0; @@ -396,7 +636,7 @@ int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) memcpy(tbf->rlc_block[index], data, len); /* Copy block. */ tbf->rlc_block_len[index] = len; tbf->dir.ul.v_n[index] = 'R'; /* Mark received block. */ - LOGP(DRLCMACDATA, LOGL_DEBUG, "- BSN %d storing in window (%d..%d)\n", + LOGP(DRLCMACUL, LOGL_DEBUG, "- BSN %d storing in window (%d..%d)\n", rh->bsn, tbf->dir.ul.v_q, (tbf->dir.ul.v_q + tbf->ws - 1) & mod_sns); /* Raise V(R) to highest received sequence number not received. */ @@ -409,7 +649,7 @@ int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) tbf->dir.ul.v_r = (tbf->dir.ul.v_r + 1) & mod_sns; /* Inc V(R). */ } - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Raising V(R) to %d\n", + LOGP(DRLCMACUL, LOGL_DEBUG, "- Raising V(R) to %d\n", tbf->dir.ul.v_r); } @@ -418,7 +658,7 @@ int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) * the window is empty.*/ while (tbf->dir.ul.v_q != tbf->dir.ul.v_r && tbf->dir.ul.v_n[ (index = tbf->dir.ul.v_q & mod_sns_half)] == 'R') { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Taking block %d out, raising " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Taking block %d out, raising " "V(Q) to %d\n", tbf->dir.ul.v_q, (tbf->dir.ul.v_q + 1) & mod_sns); /* get LLC data from block */ @@ -431,43 +671,697 @@ int gprs_rlcmac_rcv_data_block_acknowledged(uint8_t *data, uint8_t len) /* Check CV of last frame in buffer */ if (tbf->state == GPRS_RLCMAC_FLOW /* still in flow state */ && tbf->dir.ul.v_q == tbf->dir.ul.v_r) { /* if complete */ - struct rlc_dl_header *last_rh = (struct rlc_dl_header *) + struct rlc_ul_header *last_rh = (struct rlc_ul_header *) tbf->rlc_block[(tbf->dir.ul.v_r - 1) & mod_sns_half]; - LOGP(DRLCMACDATA, LOGL_DEBUG, "- No gaps in received block, " + LOGP(DRLCMACUL, LOGL_DEBUG, "- No gaps in received block, " "last block: BSN=%d CV=%d\n", last_rh->bsn, last_rh->cv); if (last_rh->cv == 0) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Finished with UL " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Finished with UL " "TBF\n"); - tbf->state = GPRS_RLCMAC_FINISHED; - /* Start special timer instead of N3103 counter. - * If this expires, resend. */ - tbf_timer_start(tbf, 3103, 1); + tbf_new_state(tbf, GPRS_RLCMAC_FINISHED); + /* Reset N3103 counter. */ tbf->dir.ul.n3103 = 0; } } /* If TLLI is included or if we received half of the window, we send * an ack/nack */ - if (rh->ti || tbf->state == GPRS_RLCMAC_FINISHED + if (rh->si || rh->ti || tbf->state == GPRS_RLCMAC_FINISHED || (tbf->dir.ul.rx_counter % ACK_AFTER_FRAMES) == 0) { + if (rh->si) { + LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, " + "because MS is stalled.\n"); + } if (rh->ti) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Scheduling Ack/Nack, " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, " "because TLLI is included.\n"); } if (tbf->state == GPRS_RLCMAC_FINISHED) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Scheduling Ack/Nack, " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, " "because last block has CV==0.\n"); } if ((tbf->dir.ul.rx_counter % ACK_AFTER_FRAMES) == 0) { - LOGP(DRLCMACDATA, LOGL_DEBUG, "- Scheduling Ack/Nack, " + LOGP(DRLCMACUL, LOGL_DEBUG, "- Scheduling Ack/Nack, " "because %d frames received.\n", ACK_AFTER_FRAMES); } - /* trigger sending at next RTS */ - tbf->dir.ul.substate = GPRS_RLCMAC_UL_SEND_ACK; + if (tbf->ul_ack_state == GPRS_RLCMAC_UL_ACK_NONE) { + /* trigger sending at next RTS */ + tbf->ul_ack_state = GPRS_RLCMAC_UL_ACK_SEND_ACK; + } else { + /* already triggered */ + LOGP(DRLCMACUL, LOGL_DEBUG, "- Sending Ack/Nack is " + "already triggered, don't schedule!\n"); + } + } + + return 0; +} + +struct msgb *gprs_rlcmac_send_packet_uplink_assignment( + struct gprs_rlcmac_tbf *tbf, uint32_t fn) +{ + struct msgb *msg; + struct gprs_rlcmac_tbf *new_tbf; + + if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { + LOGP(DRLCMACUL, LOGL_DEBUG, "Polling is already " + "sheduled for TBF=%d, so we must wait for uplink " + "assignment...\n", tbf->tfi); + return NULL; + } + + /* on down TBF we get the uplink TBF to be assigned. */ + if (tbf->direction == GPRS_RLCMAC_DL_TBF) + new_tbf = tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_UL_TBF); + else + new_tbf = tbf; + + if (!new_tbf) { + LOGP(DRLCMACUL, LOGL_ERROR, "We have a schedule for uplink " + "assignment at downlink TBF=%d, but there is no uplink " + "TBF\n", tbf->tfi); + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; + return NULL; + } + + msg = msgb_alloc(23, "rlcmac_ul_ass"); + if (!msg) + return NULL; + bitvec *ass_vec = bitvec_alloc(23); + if (!ass_vec) { + msgb_free(msg); + return NULL; + } + bitvec_unhex(ass_vec, + "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + write_packet_uplink_assignment(ass_vec, tbf->tfi, + (tbf->direction == GPRS_RLCMAC_DL_TBF), 0, 0, new_tbf->tfi, + new_tbf->dir.ul.usf, new_tbf->arfcn, new_tbf->ts, new_tbf->ta, + new_tbf->tsc, POLLING_ASSIGNMENT); + bitvec_pack(ass_vec, msgb_put(msg, 23)); + RlcMacDownlink_t * mac_control_block = (RlcMacDownlink_t *)malloc(sizeof(RlcMacDownlink_t)); + LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ TX : Packet Uplink Assignment +++++++++++++++++++++++++\n"); + decode_gsm_rlcmac_downlink(ass_vec, mac_control_block); + LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); + LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- TX : Packet Uplink Assignment -------------------------\n"); + bitvec_free(ass_vec); + +#if POLLING_ASSIGNMENT == 1 + FIXME process does not work, also the acknowledgement is not checked. + tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; + tbf->poll_fn = (fn + 13) % 2715648; + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_WAIT_ACK; +#else + tbf->ul_ass_state = GPRS_RLCMAC_UL_ASS_NONE; +#endif + + return msg; +} + +int gprs_rlcmac_rcv_rach(uint8_t ra, uint32_t Fn, int16_t qta) +{ + struct gprs_rlcmac_tbf *tbf; + uint8_t trx, ts; + int tfi, usf; /* must be signed */ + + LOGP(DRLCMAC, LOGL_DEBUG, "MS requests UL TBF on RACH, so we provide " + "one:\n"); + // Create new TBF + tfi = tfi_alloc(&trx, &ts); + if (tfi < 0) { + LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource\n"); + /* FIXME: send reject */ + return -EBUSY; + } + usf = find_free_usf(trx, ts); + if (usf < 0) { + LOGP(DRLCMAC, LOGL_NOTICE, "No PDCH ressource for USF\n"); + /* FIXME: send reject */ + return -EBUSY; + } + tbf = tbf_alloc(tfi, trx, ts); + if (qta < 0) + qta = 0; + if (qta > 252) + qta = 252; + tbf->ta = qta >> 2; + tbf->direction = GPRS_RLCMAC_UL_TBF; + tbf->dir.ul.usf = usf; + tbf_new_state(tbf, GPRS_RLCMAC_FLOW); + tbf_timer_start(tbf, 3169, T3169); + LOGP(DRLCMAC, LOGL_NOTICE, "TBF: [UPLINK] START TFI: %u\n", tbf->tfi); + LOGP(DRLCMAC, LOGL_NOTICE, "RX: [PCU <- BTS] TFI: %u RACH qbit-ta=%d ra=%d, Fn=%d (%d,%d,%d)\n", tbf->tfi, qta, ra, Fn, (Fn / (26 * 51)) % 32, Fn % 51, Fn % 26); + LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u Packet Immidiate Assignment\n", tbf->tfi); + bitvec *immediate_assignment = bitvec_alloc(23); + bitvec_unhex(immediate_assignment, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + int len = write_immediate_assignment(immediate_assignment, 0, ra, Fn, tbf->ta, tbf->arfcn, tbf->ts, tbf->tsc, tbf->tfi, usf, 0, 0, 0); + pcu_l1if_tx_agch(immediate_assignment, len); + bitvec_free(immediate_assignment); + + return 0; +} + + +/* + * DL data block flow + */ + +/* send DL data block + * + * The messages are fragmented and forwarded as data blocks. + */ +struct msgb *gprs_rlcmac_send_data_block_acknowledged( + struct gprs_rlcmac_tbf *tbf, uint32_t fn) +{ + struct gprs_rlcmac_bts *bts = gprs_rlcmac_bts; + struct rlc_dl_header *rh; + struct rlc_li_field *li; + uint8_t block_length; /* total length of block, including spare bits */ + uint8_t block_data; /* usable data of block, w/o spare bits, inc. MAC */ + struct msgb *msg, *dl_msg; + uint8_t bsn; + uint16_t mod_sns = tbf->sns - 1; + uint16_t mod_sns_half = (tbf->sns >> 1) - 1; + uint16_t index; + uint8_t *delimiter, *data, *e_pointer; + uint8_t len; + uint16_t space, chunk; + + LOGP(DRLCMACDL, LOGL_INFO, "DL DATA TFI=%d downlink (V(A)==%d .. " + "V(S)==%d)\n", tbf->tfi, tbf->dir.dl.v_a, tbf->dir.dl.v_s); + +do_resend: + /* check if there is a block with negative acknowledgement */ + for (bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; + bsn = (bsn + 1) & mod_sns) { + index = (bsn & mod_sns_half); + if (tbf->dir.dl.v_b[index] == 'N' + || tbf->dir.dl.v_b[index] == 'X') { + LOGP(DRLCMACDL, LOGL_DEBUG, "- Resending BSN %d\n", + bsn); + /* re-send block with negative aknowlegement */ + tbf->dir.dl.v_b[index] = 'U'; /* unacked */ + goto tx_block; + } + } + + /* if the window has stalled, or transfer is complete, + * send an unacknowledged block */ + if (tbf->state == GPRS_RLCMAC_FINISHED + || ((tbf->dir.dl.v_s - tbf->dir.dl.v_a) & mod_sns) == tbf->ws) { + int resend = 0; + + if (tbf->state == GPRS_RLCMAC_FINISHED) + LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " + "because all blocks have been transmitted.\n", + tbf->dir.dl.v_a); + else + LOGP(DRLCMACDL, LOGL_DEBUG, "- Restarting at BSN %d, " + "because all window is stalled.\n", + tbf->dir.dl.v_a); + /* If V(S) == V(A) and finished state, we would have received + * acknowledgement of all transmitted block. In this case we + * would have transmitted the final block, and received ack + * from MS. But in this case we did not receive the final ack + * indication from MS. This should never happen if MS works + * correctly. */ + if (tbf->dir.dl.v_s == tbf->dir.dl.v_a) { + LOGP(DRLCMACDL, LOGL_ERROR, "- MS acked all block " + "(including final block), but did not include " + "FINAL_ACK_INDICATION!\n"); + /* we just send final block again */ + index = ((tbf->dir.dl.v_s - 1) & mod_sns_half); + goto tx_block; + } + + /* cycle through all unacked blocks */ + for (bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; + bsn = (bsn + 1) & mod_sns) { + index = (bsn & mod_sns_half); + if (tbf->dir.dl.v_b[index] == 'U') { + /* mark to be re-send */ + tbf->dir.dl.v_b[index] = 'X'; + resend++; + } + } + /* At this point there should be at leasst one unacked block + * to be resent. If not, this is an software error. */ + if (resend == 0) { + LOGP(DRLCMACDL, LOGL_ERROR, "Software error: " + "There are no unacknowledged blocks, but V(A) " + " != V(S). PLEASE FIX!\n"); + /* we just send final block again */ + index = ((tbf->dir.dl.v_s - 1) & mod_sns_half); + goto tx_block; + } + goto do_resend; + } + + LOGP(DRLCMACDL, LOGL_DEBUG, "- Sending new block at BSN %d\n", + tbf->dir.dl.v_s); + + /* now we still have untransmitted LLC data, so we fill mac block */ + index = tbf->dir.dl.v_s & mod_sns_half; + data = tbf->rlc_block[index]; + switch (bts->cs) { + case 2: /* CS-2 */ + block_length = 34; + block_data = 33; + break; + case 3: /* CS-3 */ + block_length = 40; + block_data = 39; + break; + case 4: /* CS-4 */ + block_length = 54; + block_data = 53; + break; + default: /* CS-1 */ + block_length = 23; + block_data = 23; + } + memset(data, 0x2b, block_data); /* spare bits will be left 0 */ + rh = (struct rlc_dl_header *)data; + rh->pt = 0; /* Data Block */ + rh->rrbp = rh->s_p = 0; /* Polling, set later, if required */ + rh->usf = 7; /* will be set at scheduler */ + rh->pr = 0; /* FIXME: power reduction */ + rh->tfi = tbf->tfi; /* TFI */ + rh->fbi = 0; /* Final Block Indicator, set late, if true */ + rh->bsn = tbf->dir.dl.v_s; /* Block Sequence Number */ + rh->e = 0; /* Extension bit, maybe set later */ + e_pointer = data + 2; /* points to E of current chunk */ + data += 3; + delimiter = data; /* where next length header would be stored */ + space = block_data - 3; + while (1) { + chunk = tbf->llc_length - tbf->llc_index; + /* if chunk will exceed block limit */ + if (chunk > space) { + LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " + "larger than space (%d) left in block: copy " + "only remaining space, and we are done\n", + chunk, space); + /* block is filled, so there is no extension */ + *e_pointer |= 0x01; + /* fill only space */ + memcpy(data, tbf->llc_frame + tbf->llc_index, space); + /* incement index */ + tbf->llc_index += space; + /* return data block as message */ + break; + } + /* if FINAL chunk would fit precisely in space left */ + if (chunk == space && llist_empty(&tbf->llc_queue)) { + LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " + "would exactly fit into space (%d): because " + "this is a final block, we don't add length " + "header, and we are done\n", chunk, space); + /* block is filled, so there is no extension */ + *e_pointer |= 0x01; + /* fill space */ + memcpy(data, tbf->llc_frame + tbf->llc_index, space); + /* reset LLC frame */ + tbf->llc_index = tbf->llc_length = 0; + /* final block */ + rh->fbi = 1; /* we indicate final block */ + tbf_new_state(tbf, GPRS_RLCMAC_FINISHED); + /* return data block as message */ + break; + } + /* if chunk would fit exactly in space left */ + if (chunk == space) { + LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d " + "would exactly fit into space (%d): add length " + "header with LI=0, to make frame extend to " + "next block, and we are done\n", chunk, space); + /* make space for delimiter */ + if (delimiter != data) + memcpy(delimiter + 1, delimiter, + data - delimiter); + data++; + space--; + /* add LI with 0 length */ + li = (struct rlc_li_field *)delimiter; + li->e = 1; /* not more extension */ + li->m = 0; /* shall be set to 0, in case of li = 0 */ + li->li = 0; /* chunk fills the complete space */ + // no need to set e_pointer nor increase delimiter + /* fill only space, which is 1 octet less than chunk */ + memcpy(data, tbf->llc_frame + tbf->llc_index, space); + /* incement index */ + tbf->llc_index += space; + /* return data block as message */ + break; + } + LOGP(DRLCMACDL, LOGL_DEBUG, "-- Chunk with length %d is less " + "than remaining space (%d): add length header to " + "to delimit LLC frame\n", chunk, space); + /* the LLC frame chunk ends in this block */ + /* make space for delimiter */ + if (delimiter != data) + memcpy(delimiter + 1, delimiter, data - delimiter); + data++; + space--; + /* add LI to delimit frame */ + li = (struct rlc_li_field *)delimiter; + li->e = 0; /* Extension bit, maybe set later */ + li->m = 0; /* will be set later, if there is more LLC data */ + li->li = chunk; /* length of chunk */ + e_pointer = delimiter; /* points to E of current delimiter */ + delimiter++; + /* copy (rest of) LLC frame to space */ + memcpy(data, tbf->llc_frame + tbf->llc_index, chunk); + data += chunk; + space -= chunk; + /* reset LLC frame */ + tbf->llc_index = tbf->llc_length = 0; + /* dequeue next LLC frame, if any */ + msg = msgb_dequeue(&tbf->llc_queue); + if (msg) { + LOGP(DRLCMACDL, LOGL_INFO, "- Dequeue next LLC " + "(len=%d)\n", msg->len); + memcpy(tbf->llc_frame, msg->data, msg->len); + tbf->llc_length = msg->len; + msgb_free(msg); + } + /* if we have more data and we have space left */ + if (space > 0 && tbf->llc_length) { + li->m = 1; /* we indicate more frames to follow */ + continue; + } + /* if we don't have more LLC frames */ + if (!tbf->llc_length) { + LOGP(DRLCMACDL, LOGL_INFO, "-- Final block, so we " + "done.\n"); + li->e = 1; /* we cannot extend */ + rh->fbi = 1; /* we indicate final block */ + tbf_new_state(tbf, GPRS_RLCMAC_FINISHED); + break; + } + /* we have no space left */ + LOGP(DRLCMACDL, LOGL_INFO, "-- No space left, so we are " + "done.\n"); + li->e = 1; /* we cannot extend */ + break; + } + LOGP(DRLCMACDL, LOGL_DEBUG, "data block: %s\n", + osmo_hexdump(tbf->rlc_block[index], block_length)); + tbf->rlc_block_len[index] = block_length; + /* raise send state and set ack state array */ + tbf->dir.dl.v_b[index] = 'U'; /* unacked */ + tbf->dir.dl.v_s = (tbf->dir.dl.v_s + 1) & mod_sns; /* inc send state */ + +tx_block: + /* from this point on, new block is sent or old block is resent */ + + /* get data and header from current block */ + data = tbf->rlc_block[index]; + len = tbf->rlc_block_len[index]; + rh = (struct rlc_dl_header *)data; + + /* Increment TX-counter */ + tbf->dir.dl.tx_counter++; + + /* Clear Polling, if still set in history buffer */ + rh->s_p = 0; + + /* poll after ACK_AFTER_FRAMES frames, or when final block is tx. */ + if (rh->fbi == 1 || (tbf->dir.dl.tx_counter % ACK_AFTER_FRAMES) == 0) { + if (rh->fbi == 1) { + LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " + "polling, because final block sent.\n"); + } + if ((tbf->dir.dl.tx_counter % ACK_AFTER_FRAMES) == 0) { + LOGP(DRLCMACDL, LOGL_DEBUG, "- Scheduling Ack/Nack " + "polling, because %d blocks sent.\n", + ACK_AFTER_FRAMES); + } + if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) + LOGP(DRLCMACDL, LOGL_NOTICE, "Polling is already " + "sheduled for TBF=%d, so we must wait for " + "requesting downlink ack\n", tbf->tfi); + else { + /* start timer whenever we send the final block */ + if (rh->fbi == 1) + tbf_timer_start(tbf, 3191, T3191); + + /* schedule polling */ + tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; + tbf->poll_fn = (fn + 13) % 2715648; + + /* set polling in header */ + rh->rrbp = 0; /* N+13 */ + rh->s_p = 1; /* Polling */ + } } + /* return data block as message */ + dl_msg = msgb_alloc(len, "rlcmac_dl_data"); + if (!dl_msg) + return NULL; + memcpy(msgb_put(dl_msg, len), data, len); + + return dl_msg; +} + +int gprs_rlcmac_downlink_ack(struct gprs_rlcmac_tbf *tbf, uint8_t final, + uint8_t ssn, uint8_t *rbb) +{ + char show_rbb[65], show_v_b[RLC_MAX_SNS + 1]; + uint16_t mod_sns = tbf->sns - 1; + uint16_t mod_sns_half = (tbf->sns >> 1) - 1; + int i; /* must be signed */ + int16_t dist; /* must be signed */ + uint8_t bit; + uint16_t bsn; + struct msgb *msg; + + LOGP(DRLCMACDL, LOGL_INFO, "TFI=%d downlink acknowledge\n", + tbf->tfi); + + if (!final) { + /* show received array in debug (bit 64..1) */ + for (i = 63; i >= 0; i--) { + bit = (rbb[i >> 3] >> (7 - (i&7))) & 1; + show_rbb[i] = (bit) ? '1' : 'o'; + } + show_rbb[64] = '\0'; + LOGP(DRLCMACDL, LOGL_DEBUG, "- ack: (BSN=%d)\"%s\"" + "(BSN=%d) 1=ACK o=NACK\n", ssn - 64, show_rbb, + ssn - 1); + + /* apply received array to receive state (SSN-64..SSN-1) */ + /* calculate distance of ssn from V(S) */ + dist = (tbf->dir.dl.v_s - ssn) & mod_sns; + /* check if distance is less than distance V(A)..V(S) */ + if (dist < ((tbf->dir.dl.v_s - tbf->dir.dl.v_a) & mod_sns)) { + /* SSN - 1 is in range V(A)..V(S)-1 */ + for (i = 63, bsn = (ssn - 1) & mod_sns; + i >= 0 && bsn != ((tbf->dir.dl.v_a - 1) & mod_sns); + i--, bsn = (bsn - 1) & mod_sns) { + bit = (rbb[i >> 3] >> (7 - (i&7))) & 1; + if (bit) { + LOGP(DRLCMACDL, LOGL_DEBUG, "- got " + "ack for BSN=%d\n", bsn); + tbf->dir.dl.v_b[bsn & mod_sns_half] + = 'A'; + } else { + LOGP(DRLCMACDL, LOGL_DEBUG, "- got " + "NACK for BSN=%d\n", bsn); + tbf->dir.dl.v_b[bsn & mod_sns_half] + = 'N'; + } + } + } else { + LOGP(DRLCMACDL, LOGL_DEBUG, "- ack range is out of " + "V(A)..V(S) range\n"); + } + + /* raise V(A), if possible */ + for (i = 0, bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; + i++, bsn = (bsn + 1) & mod_sns) { + if (tbf->dir.dl.v_b[bsn & mod_sns_half] == 'A') { + tbf->dir.dl.v_b[bsn & mod_sns_half] = 'I'; + /* mark invalid */ + tbf->dir.dl.v_a = (tbf->dir.dl.v_a + 1) + & mod_sns; + } else + break; + } + + /* show receive state array in debug (V(A)..V(S)-1) */ + for (i = 0, bsn = tbf->dir.dl.v_a; bsn != tbf->dir.dl.v_s; + i++, bsn = (bsn + 1) & mod_sns) { + show_v_b[i] = tbf->dir.dl.v_b[bsn & mod_sns_half]; + if (show_v_b[i] == 0) + show_v_b[i] = ' '; + } + show_v_b[i] = '\0'; + LOGP(DRLCMACDL, LOGL_DEBUG, "- V(B): (V(A)=%d)\"%s\"" + "(V(S)-1=%d) A=Acked N=Nacked U=Unacked " + "X=Resend-Unacked\n", tbf->dir.dl.v_a, show_v_b, + (tbf->dir.dl.v_s - 1) & mod_sns); + + return 0; + } + + LOGP(DRLCMACDL, LOGL_DEBUG, "- Final ACK received.\n"); + + /* check for LLC PDU in the LLC Queue */ + msg = msgb_dequeue(&tbf->llc_queue); + if (!msg) { + struct gprs_rlcmac_bts *bts = gprs_rlcmac_bts; + + /* no message, start T3193, change state to RELEASE */ + LOGP(DRLCMACDL, LOGL_DEBUG, "- No new message, so we " + "release.\n"); + /* use T3192 for T3193 */ + if (bts->t3192_msec) + tbf_timer_start(tbf, 3193, bts->t3192_msec / 1000, + bts->t3192_msec & 1000); + else + tbf_timer_start(tbf, 3193, T3193); /* max T3192 */ + tbf_new_state(tbf, GPRS_RLCMAC_WAIT_RELEASE); + + return 0; + } + memcpy(tbf->llc_frame, msg->data, msg->len); + tbf->llc_length = msg->len; + msgb_free(msg); + + /* we have a message, so we trigger downlink assignment, and there + * set the state to ASSIGN. also we set old_downlink, because we + * re-use this tbf. */ + LOGP(DRLCMAC, LOGL_DEBUG, "Trigger dowlink assignment on PACCH, " + "because another LLC PDU has arrived in between\n"); + memset(&tbf->dir.dl, 0, sizeof(tbf->dir.dl)); /* reset RLC states */ + gprs_rlcmac_trigger_downlink_assignment(tbf, 1); + return 0; } + +struct msgb *gprs_rlcmac_send_packet_downlink_assignment( + struct gprs_rlcmac_tbf *tbf, uint32_t fn) +{ + struct msgb *msg; + struct gprs_rlcmac_tbf *new_tbf; + + if (tbf->poll_state != GPRS_RLCMAC_POLL_NONE) { + LOGP(DRLCMACDL, LOGL_DEBUG, "Polling is already " + "sheduled for TBF=%d, so we must wait for downlink " + "assignment...\n", tbf->tfi); + return NULL; + } + + /* on uplink TBF we get the downlink TBF to be assigned. */ + if (tbf->direction == GPRS_RLCMAC_UL_TBF) + new_tbf = tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_DL_TBF); + else + new_tbf = tbf; + if (!new_tbf) { + LOGP(DRLCMACDL, LOGL_ERROR, "We have a schedule for downlink " + "assignment at uplink TBF=%d, but there is no downlink " + "TBF\n", tbf->tfi); + tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; + return NULL; + } + + msg = msgb_alloc(23, "rlcmac_dl_ass"); + if (!msg) + return NULL; + bitvec *ass_vec = bitvec_alloc(23); + if (!ass_vec) { + msgb_free(msg); + return NULL; + } + bitvec_unhex(ass_vec, + "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + write_packet_downlink_assignment(ass_vec, tbf->tfi, + (tbf->direction == GPRS_RLCMAC_DL_TBF), new_tbf->tfi, + new_tbf->arfcn, new_tbf->ts, new_tbf->ta, new_tbf->tsc, + POLLING_ASSIGNMENT); + bitvec_pack(ass_vec, msgb_put(msg, 23)); + RlcMacDownlink_t * mac_control_block = (RlcMacDownlink_t *)malloc(sizeof(RlcMacDownlink_t)); + LOGP(DRLCMAC, LOGL_NOTICE, "+++++++++++++++++++++++++ TX : Packet Downlink Assignment +++++++++++++++++++++++++\n"); + decode_gsm_rlcmac_downlink(ass_vec, mac_control_block); + LOGPC(DRLCMAC, LOGL_NOTICE, "\n"); + LOGP(DRLCMAC, LOGL_NOTICE, "------------------------- TX : Packet Downlink Assignment -------------------------\n"); + bitvec_free(ass_vec); + +#if POLLING_ASSIGNMENT == 1 + tbf->poll_state = GPRS_RLCMAC_POLL_SCHED; + tbf->poll_fn = (fn + 13) % 2715648; + tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_WAIT_ACK; +#else + tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_NONE; +#endif + + return msg; +} + +static void gprs_rlcmac_downlink_assignment(gprs_rlcmac_tbf *tbf, uint8_t poll) +{ + LOGP(DRLCMAC, LOGL_NOTICE, "TX: [PCU -> BTS] TFI: %u TLLI: 0x%08x Immidiate Assignment (CCCH)\n", tbf->tfi, tbf->tlli); + bitvec *immediate_assignment = bitvec_alloc(23); + bitvec_unhex(immediate_assignment, "2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b2b"); + /* use request reference that has maximum distance to current time, + * so the assignment will not conflict with possible RACH requests. */ + int len = write_immediate_assignment(immediate_assignment, 1, 125, (tbf->pdch->last_rts_fn + 21216) % 2715648, tbf->ta, tbf->arfcn, tbf->ts, tbf->tsc, tbf->tfi, 0, tbf->tlli, poll, tbf->poll_fn); + pcu_l1if_tx_agch(immediate_assignment, len); + bitvec_free(immediate_assignment); +} + +/* depending on the current TBF, we assign on PACCH or AGCH */ +void gprs_rlcmac_trigger_downlink_assignment(gprs_rlcmac_tbf *tbf, + uint8_t old_downlink) +{ + gprs_rlcmac_tbf *old_tbf; + +#ifdef DEBUG_DL_ASS_IDLE + LOGP(DRLCMAC, LOGL_ERROR, "**** DEBUGGING DOWNLINK ASSIGNMENT ****\n"); +#endif + + /* stop pending timer */ + tbf_timer_stop(tbf); + + /* check for downlink tbf: */ + if (old_downlink) + old_tbf = tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_DL_TBF); + else + old_tbf = tbf_by_tlli(tbf->tlli, GPRS_RLCMAC_UL_TBF); + if (old_tbf) { +#ifdef DEBUG_DL_ASS_IDLE + LOGP(DRLCMAC, LOGL_ERROR, "We must wait for current TBF to be " + "released.\n"); + /* wait one second until assignment */ + tbf_timer_start(tbf, 1234, 1,0); +#else + LOGP(DRLCMAC, LOGL_DEBUG, "Trigger dowlink assignment on " + "PACCH, because %slink TBF=%d exists for TLLI\n", + (tbf->direction == GPRS_RLCMAC_DL_TBF) ? "down" : "up", + old_tbf->tfi); + old_tbf->dl_ass_state = GPRS_RLCMAC_DL_ASS_SEND_ASS; + /* use TA from old TBF */ + tbf->ta = old_tbf->ta; + /* change state */ + tbf_new_state(tbf, GPRS_RLCMAC_ASSIGN); + /* start timer */ + tbf_timer_start(tbf, 0, Tassign_pacch); +#endif + } else { + LOGP(DRLCMAC, LOGL_DEBUG, "Trigger dowlink assignment on AGCH, " + "because no uplink/downlink TBF exists for TLLI. " + "(providing last timing advance)\n"); + /* send immediate assignment */ + gprs_rlcmac_downlink_assignment(tbf, 0); + /* change state */ + tbf_new_state(tbf, GPRS_RLCMAC_ASSIGN); + /* start timer */ + tbf_timer_start(tbf, 0, Tassign_agch); + } + } + |