1 /******************************************************************************
2 *
3 * Copyright (C) 2004-2012 Broadcom Corporation
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 ******************************************************************************/
18
19 /******************************************************************************
20 *
21 * This file contains the L2CAP 1.2 Flow Control and retransmissions
22 * functions
23 *
24 ******************************************************************************/
25
26 #include <base/logging.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30
31 #include "bt_common.h"
32 #include "bt_types.h"
33 #include "btm_api.h"
34 #include "btm_int.h"
35 #include "btu.h"
36 #include "hcimsgs.h"
37 #include "l2c_api.h"
38 #include "l2c_int.h"
39 #include "l2cdefs.h"
40
41 extern fixed_queue_t* btu_general_alarm_queue;
42
43 /* Flag passed to retransmit_i_frames() when all packets should be retransmitted
44 */
45 #define L2C_FCR_RETX_ALL_PKTS 0xFF
46
47 /* this is the minimal offset required by OBX to process incoming packets */
48 static const uint16_t OBX_BUF_MIN_OFFSET = 4;
49
50 static const char* SAR_types[] = {"Unsegmented", "Start", "End",
51 "Continuation"};
52 static const char* SUP_types[] = {"RR", "REJ", "RNR", "SREJ"};
53
54 /* Look-up table for the CRC calculation */
55 static const unsigned short crctab[256] = {
56 0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241, 0xc601,
57 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440, 0xcc01, 0x0cc0,
58 0x0d80, 0xcd41, 0x0f00, 0xcfc1, 0xce81, 0x0e40, 0x0a00, 0xcac1, 0xcb81,
59 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841, 0xd801, 0x18c0, 0x1980, 0xd941,
60 0x1b00, 0xdbc1, 0xda81, 0x1a40, 0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01,
61 0x1dc0, 0x1c80, 0xdc41, 0x1400, 0xd4c1, 0xd581, 0x1540, 0xd701, 0x17c0,
62 0x1680, 0xd641, 0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081,
63 0x1040, 0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, 0xf281, 0x3240,
64 0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441, 0x3c00,
65 0xfcc1, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41, 0xfa01, 0x3ac0,
66 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840, 0x2800, 0xe8c1, 0xe981,
67 0x2940, 0xeb01, 0x2bc0, 0x2a80, 0xea41, 0xee01, 0x2ec0, 0x2f80, 0xef41,
68 0x2d00, 0xedc1, 0xec81, 0x2c40, 0xe401, 0x24c0, 0x2580, 0xe541, 0x2700,
69 0xe7c1, 0xe681, 0x2640, 0x2200, 0xe2c1, 0xe381, 0x2340, 0xe101, 0x21c0,
70 0x2080, 0xe041, 0xa001, 0x60c0, 0x6180, 0xa141, 0x6300, 0xa3c1, 0xa281,
71 0x6240, 0x6600, 0xa6c1, 0xa781, 0x6740, 0xa501, 0x65c0, 0x6480, 0xa441,
72 0x6c00, 0xacc1, 0xad81, 0x6d40, 0xaf01, 0x6fc0, 0x6e80, 0xae41, 0xaa01,
73 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840, 0x7800, 0xb8c1,
74 0xb981, 0x7940, 0xbb01, 0x7bc0, 0x7a80, 0xba41, 0xbe01, 0x7ec0, 0x7f80,
75 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40, 0xb401, 0x74c0, 0x7580, 0xb541,
76 0x7700, 0xb7c1, 0xb681, 0x7640, 0x7200, 0xb2c1, 0xb381, 0x7340, 0xb101,
77 0x71c0, 0x7080, 0xb041, 0x5000, 0x90c1, 0x9181, 0x5140, 0x9301, 0x53c0,
78 0x5280, 0x9241, 0x9601, 0x56c0, 0x5780, 0x9741, 0x5500, 0x95c1, 0x9481,
79 0x5440, 0x9c01, 0x5cc0, 0x5d80, 0x9d41, 0x5f00, 0x9fc1, 0x9e81, 0x5e40,
80 0x5a00, 0x9ac1, 0x9b81, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841, 0x8801,
81 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, 0x8a81, 0x4a40, 0x4e00, 0x8ec1,
82 0x8f81, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41, 0x4400, 0x84c1, 0x8581,
83 0x4540, 0x8701, 0x47c0, 0x4680, 0x8641, 0x8201, 0x42c0, 0x4380, 0x8341,
84 0x4100, 0x81c1, 0x8081, 0x4040,
85 };
86
87 /*******************************************************************************
88 * Static local functions
89 */
90 static bool process_reqseq(tL2C_CCB* p_ccb, uint16_t ctrl_word);
91 static void process_s_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word);
92 static void process_i_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word,
93 bool delay_ack);
94 static bool retransmit_i_frames(tL2C_CCB* p_ccb, uint8_t tx_seq);
95 static void prepare_I_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
96 bool is_retransmission);
97 static void process_stream_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf);
98 static bool do_sar_reassembly(tL2C_CCB* p_ccb, BT_HDR* p_buf,
99 uint16_t ctrl_word);
100
101 #if (L2CAP_ERTM_STATS == TRUE)
102 static void l2c_fcr_collect_ack_delay(tL2C_CCB* p_ccb, uint8_t num_bufs_acked);
103 #endif
104
105 /*******************************************************************************
106 *
107 * Function l2c_fcr_updcrc
108 *
109 * Description This function computes the CRC using the look-up table.
110 *
111 * Returns CRC
112 *
113 ******************************************************************************/
l2c_fcr_updcrc(unsigned short icrc,unsigned char * icp,int icnt)114 static unsigned short l2c_fcr_updcrc(unsigned short icrc, unsigned char* icp,
115 int icnt) {
116 unsigned short crc = icrc;
117 unsigned char* cp = icp;
118 int cnt = icnt;
119
120 while (cnt--) {
121 crc = ((crc >> 8) & 0xff) ^ crctab[(crc & 0xff) ^ *cp++];
122 }
123
124 return (crc);
125 }
126
127 /*******************************************************************************
128 *
129 * Function l2c_fcr_tx_get_fcs
130 *
131 * Description This function computes the CRC for a frame to be TXed.
132 *
133 * Returns CRC
134 *
135 ******************************************************************************/
l2c_fcr_tx_get_fcs(BT_HDR * p_buf)136 static uint16_t l2c_fcr_tx_get_fcs(BT_HDR* p_buf) {
137 uint8_t* p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
138
139 return (l2c_fcr_updcrc(L2CAP_FCR_INIT_CRC, p, p_buf->len));
140 }
141
142 /*******************************************************************************
143 *
144 * Function l2c_fcr_rx_get_fcs
145 *
146 * Description This function computes the CRC for a received frame.
147 *
148 * Returns CRC
149 *
150 ******************************************************************************/
l2c_fcr_rx_get_fcs(BT_HDR * p_buf)151 static uint16_t l2c_fcr_rx_get_fcs(BT_HDR* p_buf) {
152 uint8_t* p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
153
154 /* offset points past the L2CAP header, but the CRC check includes it */
155 p -= L2CAP_PKT_OVERHEAD;
156
157 return (
158 l2c_fcr_updcrc(L2CAP_FCR_INIT_CRC, p, p_buf->len + L2CAP_PKT_OVERHEAD));
159 }
160
161 /*******************************************************************************
162 *
163 * Function l2c_fcr_start_timer
164 *
165 * Description This function starts the (monitor or retransmission) timer.
166 *
167 * Returns -
168 *
169 ******************************************************************************/
l2c_fcr_start_timer(tL2C_CCB * p_ccb)170 void l2c_fcr_start_timer(tL2C_CCB* p_ccb) {
171 CHECK(p_ccb != NULL);
172 uint32_t tout;
173
174 /* The timers which are in milliseconds */
175 if (p_ccb->fcrb.wait_ack) {
176 tout = (uint32_t)p_ccb->our_cfg.fcr.mon_tout;
177 } else {
178 tout = (uint32_t)p_ccb->our_cfg.fcr.rtrans_tout;
179 }
180
181 /* Only start a timer that was not started */
182 if (!alarm_is_scheduled(p_ccb->fcrb.mon_retrans_timer)) {
183 alarm_set_on_queue(p_ccb->fcrb.mon_retrans_timer, tout,
184 l2c_ccb_timer_timeout, p_ccb, btu_general_alarm_queue);
185 }
186 }
187
188 /*******************************************************************************
189 *
190 * Function l2c_fcr_stop_timer
191 *
192 * Description This function stops the (monitor or transmission) timer.
193 *
194 * Returns -
195 *
196 ******************************************************************************/
l2c_fcr_stop_timer(tL2C_CCB * p_ccb)197 void l2c_fcr_stop_timer(tL2C_CCB* p_ccb) {
198 CHECK(p_ccb != NULL);
199 alarm_cancel(p_ccb->fcrb.mon_retrans_timer);
200 }
201
202 /*******************************************************************************
203 *
204 * Function l2c_fcr_cleanup
205 *
206 * Description This function cleans up the variable used for
207 * flow-control/retrans.
208 *
209 * Returns -
210 *
211 ******************************************************************************/
l2c_fcr_cleanup(tL2C_CCB * p_ccb)212 void l2c_fcr_cleanup(tL2C_CCB* p_ccb) {
213 CHECK(p_ccb != NULL);
214 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
215
216 alarm_free(p_fcrb->mon_retrans_timer);
217 p_fcrb->mon_retrans_timer = NULL;
218 alarm_free(p_fcrb->ack_timer);
219 p_fcrb->ack_timer = NULL;
220
221 osi_free_and_reset((void**)&p_fcrb->p_rx_sdu);
222
223 fixed_queue_free(p_fcrb->waiting_for_ack_q, osi_free);
224 p_fcrb->waiting_for_ack_q = NULL;
225
226 fixed_queue_free(p_fcrb->srej_rcv_hold_q, osi_free);
227 p_fcrb->srej_rcv_hold_q = NULL;
228
229 fixed_queue_free(p_fcrb->retrans_q, osi_free);
230 p_fcrb->retrans_q = NULL;
231
232 #if (L2CAP_ERTM_STATS == TRUE)
233 if ((p_ccb->local_cid >= L2CAP_BASE_APPL_CID) &&
234 (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)) {
235 uint32_t dur = time_get_os_boottime_ms() - p_ccb->fcrb.connect_tick_count;
236 size_t p_str_size = 120;
237 char* p_str = (char*)osi_malloc(p_str_size);
238 uint16_t i;
239 uint32_t throughput_avg, ack_delay_avg, ack_q_count_avg;
240
241 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
242 TRACE_TYPE_GENERIC,
243 "--- L2CAP ERTM Stats for CID: 0x%04x Duration: %08ums",
244 p_ccb->local_cid, dur);
245 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
246 TRACE_TYPE_GENERIC,
247 "Retransmissions:%08u Times Flow Controlled:%08u Retrans "
248 "Touts:%08u Ack Touts:%08u",
249 p_ccb->fcrb.pkts_retransmitted, p_ccb->fcrb.xmit_window_closed,
250 p_ccb->fcrb.retrans_touts, p_ccb->fcrb.xmit_ack_touts);
251 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
252 TRACE_TYPE_GENERIC,
253 "Times there is less than 2 packets in controller when flow "
254 "controlled:%08u",
255 p_ccb->fcrb.controller_idle);
256 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
257 TRACE_TYPE_GENERIC,
258 "max_held_acks:%08u, in_cfg.fcr.tx_win_sz:%08u",
259 p_ccb->fcrb.max_held_acks, p_ccb->peer_cfg.fcr.tx_win_sz);
260
261 snprintf(
262 p_str, p_str_size,
263 "Sent Pkts:%08u Bytes:%10u(%06u/sec) RR:%08u REJ:%08u RNR:%08u "
264 "SREJ:%08u",
265 p_ccb->fcrb.ertm_pkt_counts[0], p_ccb->fcrb.ertm_byte_counts[0],
266 (dur >= 10 ? (p_ccb->fcrb.ertm_byte_counts[0] * 100) / (dur / 10) : 0),
267 p_ccb->fcrb.s_frames_sent[0], p_ccb->fcrb.s_frames_sent[1],
268 p_ccb->fcrb.s_frames_sent[2], p_ccb->fcrb.s_frames_sent[3]);
269
270 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
271 TRACE_TYPE_GENERIC, "%s", p_str);
272
273 snprintf(
274 p_str, p_str_size,
275 "Rcvd Pkts:%08u Bytes:%10u(%06u/sec) RR:%08u REJ:%08u RNR:%08u "
276 "SREJ:%08u",
277 p_ccb->fcrb.ertm_pkt_counts[1], p_ccb->fcrb.ertm_byte_counts[1],
278 (dur >= 10 ? (p_ccb->fcrb.ertm_byte_counts[1] * 100) / (dur / 10) : 0),
279 p_ccb->fcrb.s_frames_rcvd[0], p_ccb->fcrb.s_frames_rcvd[1],
280 p_ccb->fcrb.s_frames_rcvd[2], p_ccb->fcrb.s_frames_rcvd[3]);
281
282 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
283 TRACE_TYPE_GENERIC, "%s", p_str);
284
285 throughput_avg = 0;
286 ack_delay_avg = 0;
287 ack_q_count_avg = 0;
288
289 for (i = 0; i < L2CAP_ERTM_STATS_NUM_AVG; i++) {
290 if (i == p_ccb->fcrb.ack_delay_avg_index) {
291 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
292 TRACE_TYPE_GENERIC, "[%02u] collecting data ...", i);
293 continue;
294 }
295
296 snprintf(p_str, p_str_size,
297 "[%02u] throughput: %5u, ack_delay avg:%3u, min:%3u, max:%3u, "
298 "ack_q_count avg:%3u, min:%3u, max:%3u",
299 i, p_ccb->fcrb.throughput[i], p_ccb->fcrb.ack_delay_avg[i],
300 p_ccb->fcrb.ack_delay_min[i], p_ccb->fcrb.ack_delay_max[i],
301 p_ccb->fcrb.ack_q_count_avg[i], p_ccb->fcrb.ack_q_count_min[i],
302 p_ccb->fcrb.ack_q_count_max[i]);
303
304 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
305 TRACE_TYPE_GENERIC, "%s", p_str);
306
307 throughput_avg += p_ccb->fcrb.throughput[i];
308 ack_delay_avg += p_ccb->fcrb.ack_delay_avg[i];
309 ack_q_count_avg += p_ccb->fcrb.ack_q_count_avg[i];
310 }
311
312 throughput_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
313 ack_delay_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
314 ack_q_count_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
315
316 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
317 TRACE_TYPE_GENERIC,
318 "throughput_avg: %8u (kbytes/sec), ack_delay_avg: %8u ms, "
319 "ack_q_count_avg: %8u",
320 throughput_avg, ack_delay_avg, ack_q_count_avg);
321
322 osi_free(p_str);
323
324 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
325 TRACE_TYPE_GENERIC, "---");
326 }
327 #endif
328
329 memset(p_fcrb, 0, sizeof(tL2C_FCRB));
330 }
331
332 /*******************************************************************************
333 *
334 * Function l2c_fcr_clone_buf
335 *
336 * Description This function allocates and copies requested part of a
337 * buffer at a new-offset.
338 *
339 * Returns pointer to new buffer
340 *
341 ******************************************************************************/
l2c_fcr_clone_buf(BT_HDR * p_buf,uint16_t new_offset,uint16_t no_of_bytes)342 BT_HDR* l2c_fcr_clone_buf(BT_HDR* p_buf, uint16_t new_offset,
343 uint16_t no_of_bytes) {
344 CHECK(p_buf != NULL);
345 /*
346 * NOTE: We allocate extra L2CAP_FCS_LEN octets, in case we need to put
347 * the FCS (Frame Check Sequence) at the end of the buffer.
348 */
349 uint16_t buf_size = no_of_bytes + sizeof(BT_HDR) + new_offset + L2CAP_FCS_LEN;
350 #if (L2CAP_ERTM_STATS == TRUE)
351 /*
352 * NOTE: If L2CAP_ERTM_STATS is enabled, we need 4 extra octets at the
353 * end for a timestamp at the end of an I-frame.
354 */
355 buf_size += sizeof(uint32_t);
356 #endif
357 BT_HDR* p_buf2 = (BT_HDR*)osi_malloc(buf_size);
358
359 p_buf2->offset = new_offset;
360 p_buf2->len = no_of_bytes;
361 memcpy(((uint8_t*)(p_buf2 + 1)) + p_buf2->offset,
362 ((uint8_t*)(p_buf + 1)) + p_buf->offset, no_of_bytes);
363
364 return (p_buf2);
365 }
366
367 /*******************************************************************************
368 *
369 * Function l2c_fcr_is_flow_controlled
370 *
371 * Description This function checks if the CCB is flow controlled by peer.
372 *
373 * Returns The control word
374 *
375 ******************************************************************************/
l2c_fcr_is_flow_controlled(tL2C_CCB * p_ccb)376 bool l2c_fcr_is_flow_controlled(tL2C_CCB* p_ccb) {
377 CHECK(p_ccb != NULL);
378 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
379 /* Check if remote side flowed us off or the transmit window is full */
380 if ((p_ccb->fcrb.remote_busy == true) ||
381 (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q) >=
382 p_ccb->peer_cfg.fcr.tx_win_sz)) {
383 #if (L2CAP_ERTM_STATS == TRUE)
384 if (!fixed_queue_is_empty(p_ccb->xmit_hold_q)) {
385 p_ccb->fcrb.xmit_window_closed++;
386
387 if ((p_ccb->p_lcb->sent_not_acked < 2) &&
388 (l2cb.controller_xmit_window > 0))
389 p_ccb->fcrb.controller_idle++;
390 }
391 #endif
392 return (true);
393 }
394 }
395 return (false);
396 }
397
398 /*******************************************************************************
399 *
400 * Function prepare_I_frame
401 *
402 * Description This function sets the FCR variables in an I-frame that is
403 * about to be sent to HCI for transmission. This may be the
404 * first time the I-frame is sent, or a retransmission
405 *
406 * Returns -
407 *
408 ******************************************************************************/
prepare_I_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,bool is_retransmission)409 static void prepare_I_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
410 bool is_retransmission) {
411 CHECK(p_ccb != NULL);
412 CHECK(p_buf != NULL);
413 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
414 uint8_t* p;
415 uint16_t fcs;
416 uint16_t ctrl_word;
417 bool set_f_bit = p_fcrb->send_f_rsp;
418
419 p_fcrb->send_f_rsp = false;
420
421 if (is_retransmission) {
422 /* Get the old control word and clear out the old req_seq and F bits */
423 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
424
425 STREAM_TO_UINT16(ctrl_word, p);
426
427 ctrl_word &= ~(L2CAP_FCR_REQ_SEQ_BITS + L2CAP_FCR_F_BIT);
428 } else {
429 ctrl_word = p_buf->layer_specific & L2CAP_FCR_SEG_BITS; /* SAR bits */
430 ctrl_word |=
431 (p_fcrb->next_tx_seq << L2CAP_FCR_TX_SEQ_BITS_SHIFT); /* Tx Seq */
432
433 p_fcrb->next_tx_seq = (p_fcrb->next_tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
434 }
435
436 /* Set the F-bit and reqseq only if using re-transmission mode */
437 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
438 if (set_f_bit) ctrl_word |= L2CAP_FCR_F_BIT;
439
440 ctrl_word |= (p_fcrb->next_seq_expected) << L2CAP_FCR_REQ_SEQ_BITS_SHIFT;
441
442 p_fcrb->last_ack_sent = p_ccb->fcrb.next_seq_expected;
443
444 alarm_cancel(p_ccb->fcrb.ack_timer);
445 }
446
447 /* Set the control word */
448 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
449
450 UINT16_TO_STREAM(p, ctrl_word);
451
452 /* Compute the FCS and add to the end of the buffer if not bypassed */
453 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
454 /* length field in l2cap header has to include FCS length */
455 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
456 UINT16_TO_STREAM(p, p_buf->len + L2CAP_FCS_LEN - L2CAP_PKT_OVERHEAD);
457
458 /* Calculate the FCS */
459 fcs = l2c_fcr_tx_get_fcs(p_buf);
460
461 /* Point to the end of the buffer and put the FCS there */
462 /*
463 * NOTE: Here we assume the allocated buffer is large enough
464 * to include extra L2CAP_FCS_LEN octets at the end.
465 */
466 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len;
467
468 UINT16_TO_STREAM(p, fcs);
469
470 p_buf->len += L2CAP_FCS_LEN;
471 }
472
473 if (is_retransmission) {
474 L2CAP_TRACE_EVENT(
475 "L2CAP eRTM ReTx I-frame CID: 0x%04x Len: %u SAR: %s TxSeq: %u "
476 "ReqSeq: %u F: %u",
477 p_ccb->local_cid, p_buf->len,
478 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
479 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
480 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
481 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
482 } else {
483 L2CAP_TRACE_EVENT(
484 "L2CAP eRTM Tx I-frame CID: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
485 "ReqSeq: %u F: %u",
486 p_ccb->local_cid, p_buf->len,
487 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
488 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
489 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
490 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
491 }
492
493 /* Start the retransmission timer if not already running */
494 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)
495 l2c_fcr_start_timer(p_ccb);
496 }
497
498 /*******************************************************************************
499 *
500 * Function l2c_fcr_send_S_frame
501 *
502 * Description This function formats and sends an S-frame for transmission.
503 *
504 * Returns -
505 *
506 ******************************************************************************/
l2c_fcr_send_S_frame(tL2C_CCB * p_ccb,uint16_t function_code,uint16_t pf_bit)507 void l2c_fcr_send_S_frame(tL2C_CCB* p_ccb, uint16_t function_code,
508 uint16_t pf_bit) {
509 CHECK(p_ccb != NULL);
510 uint8_t* p;
511 uint16_t ctrl_word;
512 uint16_t fcs;
513
514 if ((!p_ccb->in_use) || (p_ccb->chnl_state != CST_OPEN)) return;
515
516 #if (L2CAP_ERTM_STATS == TRUE)
517 p_ccb->fcrb.s_frames_sent[function_code]++;
518 #endif
519
520 if (pf_bit == L2CAP_FCR_P_BIT) {
521 p_ccb->fcrb.wait_ack = true;
522
523 l2c_fcr_stop_timer(p_ccb); /* Restart the monitor timer */
524 l2c_fcr_start_timer(p_ccb);
525 }
526
527 /* Create the control word to use */
528 ctrl_word = (function_code << L2CAP_FCR_SUP_SHIFT) | L2CAP_FCR_S_FRAME_BIT;
529 ctrl_word |= (p_ccb->fcrb.next_seq_expected << L2CAP_FCR_REQ_SEQ_BITS_SHIFT);
530 ctrl_word |= pf_bit;
531
532 BT_HDR* p_buf = (BT_HDR*)osi_malloc(L2CAP_CMD_BUF_SIZE);
533 p_buf->offset = HCI_DATA_PREAMBLE_SIZE;
534 p_buf->len = L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD;
535
536 /* Set the pointer to the beginning of the data */
537 p = (uint8_t*)(p_buf + 1) + p_buf->offset;
538
539 /* Put in the L2CAP header */
540 UINT16_TO_STREAM(p, L2CAP_FCR_OVERHEAD + L2CAP_FCS_LEN);
541 UINT16_TO_STREAM(p, p_ccb->remote_cid);
542 UINT16_TO_STREAM(p, ctrl_word);
543
544 /* Compute the FCS and add to the end of the buffer if not bypassed */
545 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
546 fcs = l2c_fcr_tx_get_fcs(p_buf);
547
548 UINT16_TO_STREAM(p, fcs);
549 p_buf->len += L2CAP_FCS_LEN;
550 } else {
551 /* rewrite the length without FCS length */
552 p -= 6;
553 UINT16_TO_STREAM(p, L2CAP_FCR_OVERHEAD);
554 }
555
556 /* Now, the HCI transport header */
557 p_buf->layer_specific = L2CAP_NON_FLUSHABLE_PKT;
558 l2cu_set_acl_hci_header(p_buf, p_ccb);
559
560 if ((((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 1) ||
561 (((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 3)) {
562 L2CAP_TRACE_WARNING(
563 "L2CAP eRTM Tx S-frame CID: 0x%04x ctrlword: 0x%04x Type: %s "
564 "ReqSeq: %u P: %u F: %u",
565 p_ccb->local_cid, ctrl_word,
566 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
567 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
568 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
569 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
570 L2CAP_TRACE_WARNING(" Buf Len: %u", p_buf->len);
571 } else {
572 L2CAP_TRACE_EVENT(
573 "L2CAP eRTM Tx S-frame CID: 0x%04x ctrlword: 0x%04x Type: %s "
574 "ReqSeq: %u P: %u F: %u",
575 p_ccb->local_cid, ctrl_word,
576 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
577 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
578 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
579 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
580 L2CAP_TRACE_EVENT(" Buf Len: %u", p_buf->len);
581 }
582
583 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, p_buf);
584
585 p_ccb->fcrb.last_ack_sent = p_ccb->fcrb.next_seq_expected;
586
587 alarm_cancel(p_ccb->fcrb.ack_timer);
588 }
589
590 /*******************************************************************************
591 *
592 * Function l2c_fcr_proc_pdu
593 *
594 * Description This function is the entry point for processing of a
595 * received PDU when in flow control and/or retransmission
596 * modes.
597 *
598 * Returns -
599 *
600 ******************************************************************************/
l2c_fcr_proc_pdu(tL2C_CCB * p_ccb,BT_HDR * p_buf)601 void l2c_fcr_proc_pdu(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
602 CHECK(p_ccb != NULL);
603 CHECK(p_buf != NULL);
604 uint8_t* p;
605 uint16_t fcs;
606 uint16_t min_pdu_len;
607 uint16_t ctrl_word;
608
609 /* Check the length */
610 min_pdu_len = (p_ccb->bypass_fcs == L2CAP_BYPASS_FCS)
611 ? (uint16_t)L2CAP_FCR_OVERHEAD
612 : (uint16_t)(L2CAP_FCS_LEN + L2CAP_FCR_OVERHEAD);
613
614 if (p_buf->len < min_pdu_len) {
615 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x Len too short: %u",
616 p_ccb->local_cid, p_buf->len);
617 osi_free(p_buf);
618 return;
619 }
620
621 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_STREAM_MODE) {
622 process_stream_frame(p_ccb, p_buf);
623 return;
624 }
625
626 /* Get the control word */
627 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
628 STREAM_TO_UINT16(ctrl_word, p);
629
630 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) {
631 if ((((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 1) ||
632 (((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 3)) {
633 /* REJ or SREJ */
634 L2CAP_TRACE_WARNING(
635 "L2CAP eRTM Rx S-frame: cid: 0x%04x Len: %u Type: %s ReqSeq: %u "
636 "P: %u F: %u",
637 p_ccb->local_cid, p_buf->len,
638 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
639 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
640 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
641 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
642 } else {
643 L2CAP_TRACE_EVENT(
644 "L2CAP eRTM Rx S-frame: cid: 0x%04x Len: %u Type: %s ReqSeq: %u "
645 "P: %u F: %u",
646 p_ccb->local_cid, p_buf->len,
647 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
648 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
649 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
650 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
651 }
652 } else {
653 L2CAP_TRACE_EVENT(
654 "L2CAP eRTM Rx I-frame: cid: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
655 "ReqSeq: %u F: %u",
656 p_ccb->local_cid, p_buf->len,
657 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
658 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
659 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
660 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
661 }
662
663 L2CAP_TRACE_EVENT(
664 " eRTM Rx Nxt_tx_seq %u, Lst_rx_ack %u, Nxt_seq_exp %u, Lst_ack_snt "
665 "%u, wt_q.cnt %u, tries %u",
666 p_ccb->fcrb.next_tx_seq, p_ccb->fcrb.last_rx_ack,
667 p_ccb->fcrb.next_seq_expected, p_ccb->fcrb.last_ack_sent,
668 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q), p_ccb->fcrb.num_tries);
669
670 /* Verify FCS if using */
671 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
672 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len - L2CAP_FCS_LEN;
673
674 /* Extract and drop the FCS from the packet */
675 STREAM_TO_UINT16(fcs, p);
676 p_buf->len -= L2CAP_FCS_LEN;
677
678 if (l2c_fcr_rx_get_fcs(p_buf) != fcs) {
679 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x BAD FCS",
680 p_ccb->local_cid);
681 osi_free(p_buf);
682 return;
683 }
684 }
685
686 /* Get the control word */
687 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
688
689 STREAM_TO_UINT16(ctrl_word, p);
690
691 p_buf->len -= L2CAP_FCR_OVERHEAD;
692 p_buf->offset += L2CAP_FCR_OVERHEAD;
693
694 /* If we had a poll bit outstanding, check if we got a final response */
695 if (p_ccb->fcrb.wait_ack) {
696 /* If final bit not set, ignore the frame unless it is a polled S-frame */
697 if (!(ctrl_word & L2CAP_FCR_F_BIT)) {
698 if ((ctrl_word & L2CAP_FCR_P_BIT) &&
699 (ctrl_word & L2CAP_FCR_S_FRAME_BIT)) {
700 if (p_ccb->fcrb.srej_sent)
701 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, L2CAP_FCR_F_BIT);
702 else if (p_ccb->fcrb.local_busy)
703 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_F_BIT);
704 else
705 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_F_BIT);
706
707 /* Got a poll while in wait_ack state, so re-start our timer with
708 * 1-second */
709 /* This is a small optimization... the monitor timer is 12 secs, but we
710 * saw */
711 /* that if the other side sends us a poll when we are waiting for a
712 * final, */
713 /* then it speeds up recovery significantly if we poll him back soon
714 * after his poll. */
715 alarm_set_on_queue(p_ccb->fcrb.mon_retrans_timer, BT_1SEC_TIMEOUT_MS,
716 l2c_ccb_timer_timeout, p_ccb,
717 btu_general_alarm_queue);
718 }
719 osi_free(p_buf);
720 return;
721 }
722
723 p_ccb->fcrb.wait_ack = false;
724
725 /* P and F are mutually exclusive */
726 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) ctrl_word &= ~L2CAP_FCR_P_BIT;
727
728 if (fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q))
729 p_ccb->fcrb.num_tries = 0;
730
731 l2c_fcr_stop_timer(p_ccb);
732 } else {
733 /* Otherwise, ensure the final bit is ignored */
734 ctrl_word &= ~L2CAP_FCR_F_BIT;
735 }
736
737 /* Process receive sequence number */
738 if (!process_reqseq(p_ccb, ctrl_word)) {
739 osi_free(p_buf);
740 return;
741 }
742
743 /* Process based on whether it is an S-frame or an I-frame */
744 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT)
745 process_s_frame(p_ccb, p_buf, ctrl_word);
746 else
747 process_i_frame(p_ccb, p_buf, ctrl_word, false);
748
749 /* Return if the channel got disconnected by a bad packet or max
750 * retransmissions */
751 if ((!p_ccb->in_use) || (p_ccb->chnl_state != CST_OPEN)) return;
752
753 /* If we have some buffers held while doing SREJ, and SREJ has cleared,
754 * process them now */
755 if ((!p_ccb->fcrb.local_busy) && (!p_ccb->fcrb.srej_sent) &&
756 (!fixed_queue_is_empty(p_ccb->fcrb.srej_rcv_hold_q))) {
757 fixed_queue_t* temp_q = p_ccb->fcrb.srej_rcv_hold_q;
758 p_ccb->fcrb.srej_rcv_hold_q = fixed_queue_new(SIZE_MAX);
759
760 while ((p_buf = (BT_HDR*)fixed_queue_try_dequeue(temp_q)) != NULL) {
761 if (p_ccb->in_use && (p_ccb->chnl_state == CST_OPEN)) {
762 /* Get the control word */
763 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset - L2CAP_FCR_OVERHEAD;
764
765 STREAM_TO_UINT16(ctrl_word, p);
766
767 L2CAP_TRACE_DEBUG(
768 "l2c_fcr_proc_pdu() CID: 0x%04x Process Buffer from SREJ_Hold_Q "
769 "TxSeq: %u Expected_Seq: %u",
770 p_ccb->local_cid,
771 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
772 p_ccb->fcrb.next_seq_expected);
773
774 /* Process the SREJ held I-frame, but do not send an RR for each
775 * individual frame */
776 process_i_frame(p_ccb, p_buf, ctrl_word, true);
777 } else
778 osi_free(p_buf);
779
780 /* If more frames were lost during SREJ, send a REJ */
781 if (p_ccb->fcrb.rej_after_srej) {
782 p_ccb->fcrb.rej_after_srej = false;
783 p_ccb->fcrb.rej_sent = true;
784
785 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_REJ, 0);
786 }
787 }
788 fixed_queue_free(temp_q, NULL);
789
790 /* Now, if needed, send one RR for the whole held queue */
791 if ((!p_ccb->fcrb.local_busy) && (!p_ccb->fcrb.rej_sent) &&
792 (!p_ccb->fcrb.srej_sent) &&
793 (p_ccb->fcrb.next_seq_expected != p_ccb->fcrb.last_ack_sent))
794 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
795 else {
796 L2CAP_TRACE_DEBUG(
797 "l2c_fcr_proc_pdu() not sending RR CID: 0x%04x local_busy:%d "
798 "rej_sent:%d srej_sent:%d Expected_Seq:%u Last_Ack:%u",
799 p_ccb->local_cid, p_ccb->fcrb.local_busy, p_ccb->fcrb.rej_sent,
800 p_ccb->fcrb.srej_sent, p_ccb->fcrb.next_seq_expected,
801 p_ccb->fcrb.last_ack_sent);
802 }
803 }
804
805 /* If a window has opened, check if we can send any more packets */
806 if ((!fixed_queue_is_empty(p_ccb->fcrb.retrans_q) ||
807 !fixed_queue_is_empty(p_ccb->xmit_hold_q)) &&
808 (p_ccb->fcrb.wait_ack == false) &&
809 (l2c_fcr_is_flow_controlled(p_ccb) == false)) {
810 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, NULL);
811 }
812 }
813
814 /*******************************************************************************
815 *
816 * Function l2c_lcc_proc_pdu
817 *
818 * Description This function is the entry point for processing of a
819 * received PDU when in LE Coc flow control modes.
820 *
821 * Returns -
822 *
823 ******************************************************************************/
l2c_lcc_proc_pdu(tL2C_CCB * p_ccb,BT_HDR * p_buf)824 void l2c_lcc_proc_pdu(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
825 CHECK(p_ccb != NULL);
826 CHECK(p_buf != NULL);
827 uint8_t* p = (uint8_t*)(p_buf + 1) + p_buf->offset;
828 uint16_t sdu_length;
829 BT_HDR* p_data = NULL;
830
831 /* Buffer length should not exceed local mps */
832 if (p_buf->len > p_ccb->local_conn_cfg.mps) {
833 /* Discard the buffer */
834 osi_free(p_buf);
835 return;
836 }
837
838 if (p_ccb->is_first_seg) {
839 STREAM_TO_UINT16(sdu_length, p);
840 /* Check the SDU Length with local MTU size */
841 if (sdu_length > p_ccb->local_conn_cfg.mtu) {
842 /* Discard the buffer */
843 osi_free(p_buf);
844 return;
845 }
846
847 p_data = (BT_HDR*)osi_malloc(L2CAP_MAX_BUF_SIZE);
848 if (p_data == NULL) {
849 osi_free(p_buf);
850 return;
851 }
852
853 p_ccb->ble_sdu = p_data;
854 p_data->len = 0;
855 p_ccb->ble_sdu_length = sdu_length;
856 L2CAP_TRACE_DEBUG("%s SDU Length = %d", __func__, sdu_length);
857 p_buf->len -= sizeof(sdu_length);
858 p_buf->offset += sizeof(sdu_length);
859 p_data->offset = 0;
860
861 } else
862 p_data = p_ccb->ble_sdu;
863
864 memcpy((uint8_t*)(p_data + 1) + p_data->offset + p_data->len,
865 (uint8_t*)(p_buf + 1) + p_buf->offset, p_buf->len);
866 p_data->len += p_buf->len;
867 p = (uint8_t*)(p_data + 1) + p_data->offset;
868 if (p_data->len == p_ccb->ble_sdu_length) {
869 l2c_csm_execute(p_ccb, L2CEVT_L2CAP_DATA, p_data);
870 p_ccb->is_first_seg = true;
871 p_ccb->ble_sdu = NULL;
872 p_ccb->ble_sdu_length = 0;
873 } else if (p_data->len < p_ccb->ble_sdu_length) {
874 p_ccb->is_first_seg = false;
875 } else {
876 L2CAP_TRACE_ERROR("%s Length in the SDU messed up", __func__);
877 // TODO: reset every thing may be???
878 }
879
880 osi_free(p_buf);
881 return;
882 }
883
884 /*******************************************************************************
885 *
886 * Function l2c_fcr_proc_tout
887 *
888 * Description Handle a timeout. We should be in error recovery state.
889 *
890 * Returns -
891 *
892 ******************************************************************************/
l2c_fcr_proc_tout(tL2C_CCB * p_ccb)893 void l2c_fcr_proc_tout(tL2C_CCB* p_ccb) {
894 CHECK(p_ccb != NULL);
895 L2CAP_TRACE_DEBUG(
896 "l2c_fcr_proc_tout: CID: 0x%04x num_tries: %u (max: %u) wait_ack: %u "
897 "ack_q_count: %u",
898 p_ccb->local_cid, p_ccb->fcrb.num_tries, p_ccb->peer_cfg.fcr.max_transmit,
899 p_ccb->fcrb.wait_ack, fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
900
901 #if (L2CAP_ERTM_STATS == TRUE)
902 p_ccb->fcrb.retrans_touts++;
903 #endif
904
905 if ((p_ccb->peer_cfg.fcr.max_transmit != 0) &&
906 (++p_ccb->fcrb.num_tries > p_ccb->peer_cfg.fcr.max_transmit)) {
907 l2cu_disconnect_chnl(p_ccb);
908 } else {
909 if (!p_ccb->fcrb.srej_sent && !p_ccb->fcrb.rej_sent) {
910 if (p_ccb->fcrb.local_busy)
911 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_P_BIT);
912 else
913 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_P_BIT);
914 }
915 }
916 }
917
918 /*******************************************************************************
919 *
920 * Function l2c_fcr_proc_ack_tout
921 *
922 * Description Send RR/RNR if we have not acked I frame
923 *
924 * Returns -
925 *
926 ******************************************************************************/
l2c_fcr_proc_ack_tout(tL2C_CCB * p_ccb)927 void l2c_fcr_proc_ack_tout(tL2C_CCB* p_ccb) {
928 CHECK(p_ccb != NULL);
929 L2CAP_TRACE_DEBUG(
930 "l2c_fcr_proc_ack_tout: CID: 0x%04x State: %u Wack:%u Rq:%d Acked:%d",
931 p_ccb->local_cid, p_ccb->chnl_state, p_ccb->fcrb.wait_ack,
932 p_ccb->fcrb.next_seq_expected, p_ccb->fcrb.last_ack_sent);
933
934 if ((p_ccb->chnl_state == CST_OPEN) && (!p_ccb->fcrb.wait_ack) &&
935 (p_ccb->fcrb.last_ack_sent != p_ccb->fcrb.next_seq_expected)) {
936 #if (L2CAP_ERTM_STATS == TRUE)
937 p_ccb->fcrb.xmit_ack_touts++;
938 #endif
939 if (p_ccb->fcrb.local_busy)
940 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
941 else
942 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
943 }
944 }
945
946 /*******************************************************************************
947 *
948 * Function process_reqseq
949 *
950 * Description Handle receive sequence number
951 *
952 * Returns -
953 *
954 ******************************************************************************/
process_reqseq(tL2C_CCB * p_ccb,uint16_t ctrl_word)955 static bool process_reqseq(tL2C_CCB* p_ccb, uint16_t ctrl_word) {
956 CHECK(p_ccb != NULL);
957 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
958 uint8_t req_seq, num_bufs_acked, xx;
959 uint16_t ls;
960 uint16_t full_sdus_xmitted;
961
962 /* Receive sequence number does not ack anything for SREJ with P-bit set to
963 * zero */
964 if ((ctrl_word & L2CAP_FCR_S_FRAME_BIT) &&
965 ((ctrl_word & L2CAP_FCR_SUP_BITS) ==
966 (L2CAP_FCR_SUP_SREJ << L2CAP_FCR_SUP_SHIFT)) &&
967 ((ctrl_word & L2CAP_FCR_P_BIT) == 0)) {
968 /* If anything still waiting for ack, restart the timer if it was stopped */
969 if (!fixed_queue_is_empty(p_fcrb->waiting_for_ack_q))
970 l2c_fcr_start_timer(p_ccb);
971
972 return (true);
973 }
974
975 /* Extract the receive sequence number from the control word */
976 req_seq =
977 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT;
978
979 num_bufs_acked = (req_seq - p_fcrb->last_rx_ack) & L2CAP_FCR_SEQ_MODULO;
980
981 /* Verify the request sequence is in range before proceeding */
982 if (num_bufs_acked > fixed_queue_length(p_fcrb->waiting_for_ack_q)) {
983 /* The channel is closed if ReqSeq is not in range */
984 L2CAP_TRACE_WARNING(
985 "L2CAP eRTM Frame BAD Req_Seq - ctrl_word: 0x%04x req_seq 0x%02x "
986 "last_rx_ack: 0x%02x QCount: %u",
987 ctrl_word, req_seq, p_fcrb->last_rx_ack,
988 fixed_queue_length(p_fcrb->waiting_for_ack_q));
989
990 l2cu_disconnect_chnl(p_ccb);
991 return (false);
992 }
993
994 p_fcrb->last_rx_ack = req_seq;
995
996 /* Now we can release all acknowledged frames, and restart the retransmission
997 * timer if needed */
998 if (num_bufs_acked != 0) {
999 p_fcrb->num_tries = 0;
1000 full_sdus_xmitted = 0;
1001
1002 #if (L2CAP_ERTM_STATS == TRUE)
1003 l2c_fcr_collect_ack_delay(p_ccb, num_bufs_acked);
1004 #endif
1005
1006 for (xx = 0; xx < num_bufs_acked; xx++) {
1007 BT_HDR* p_tmp =
1008 (BT_HDR*)fixed_queue_try_dequeue(p_fcrb->waiting_for_ack_q);
1009 ls = p_tmp->layer_specific & L2CAP_FCR_SAR_BITS;
1010
1011 if ((ls == L2CAP_FCR_UNSEG_SDU) || (ls == L2CAP_FCR_END_SDU))
1012 full_sdus_xmitted++;
1013
1014 osi_free(p_tmp);
1015 }
1016
1017 /* If we are still in a wait_ack state, do not mess with the timer */
1018 if (!p_ccb->fcrb.wait_ack) l2c_fcr_stop_timer(p_ccb);
1019
1020 /* Check if we need to call the "packet_sent" callback */
1021 if ((p_ccb->p_rcb) && (p_ccb->p_rcb->api.pL2CA_TxComplete_Cb) &&
1022 (full_sdus_xmitted)) {
1023 /* Special case for eRTM, if all packets sent, send 0xFFFF */
1024 if (fixed_queue_is_empty(p_fcrb->waiting_for_ack_q) &&
1025 fixed_queue_is_empty(p_ccb->xmit_hold_q)) {
1026 full_sdus_xmitted = 0xFFFF;
1027 }
1028
1029 (*p_ccb->p_rcb->api.pL2CA_TxComplete_Cb)(p_ccb->local_cid,
1030 full_sdus_xmitted);
1031 }
1032 }
1033
1034 /* If anything still waiting for ack, restart the timer if it was stopped */
1035 if (!fixed_queue_is_empty(p_fcrb->waiting_for_ack_q))
1036 l2c_fcr_start_timer(p_ccb);
1037 return (true);
1038 }
1039
1040 /*******************************************************************************
1041 *
1042 * Function process_s_frame
1043 *
1044 * Description Process an S frame
1045 *
1046 * Returns -
1047 *
1048 ******************************************************************************/
process_s_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word)1049 static void process_s_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
1050 uint16_t ctrl_word) {
1051 CHECK(p_ccb != NULL);
1052 CHECK(p_buf != NULL);
1053
1054 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1055 uint16_t s_frame_type =
1056 (ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT;
1057 bool remote_was_busy;
1058 bool all_ok = true;
1059
1060 if (p_buf->len != 0) {
1061 L2CAP_TRACE_WARNING("Incorrect S-frame Length (%d)", p_buf->len);
1062 }
1063
1064 L2CAP_TRACE_DEBUG("process_s_frame ctrl_word 0x%04x fcrb_remote_busy:%d",
1065 ctrl_word, p_fcrb->remote_busy);
1066
1067 #if (L2CAP_ERTM_STATS == TRUE)
1068 p_ccb->fcrb.s_frames_rcvd[s_frame_type]++;
1069 #endif
1070
1071 if (ctrl_word & L2CAP_FCR_P_BIT) {
1072 p_fcrb->rej_sent = false; /* After checkpoint, we can send anoher REJ */
1073 p_fcrb->send_f_rsp = true; /* Set a flag in case an I-frame is pending */
1074 }
1075
1076 switch (s_frame_type) {
1077 case L2CAP_FCR_SUP_RR:
1078 remote_was_busy = p_fcrb->remote_busy;
1079 p_fcrb->remote_busy = false;
1080
1081 if ((ctrl_word & L2CAP_FCR_F_BIT) || (remote_was_busy))
1082 all_ok = retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS);
1083 break;
1084
1085 case L2CAP_FCR_SUP_REJ:
1086 p_fcrb->remote_busy = false;
1087 all_ok = retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS);
1088 break;
1089
1090 case L2CAP_FCR_SUP_RNR:
1091 p_fcrb->remote_busy = true;
1092 l2c_fcr_stop_timer(p_ccb);
1093 break;
1094
1095 case L2CAP_FCR_SUP_SREJ:
1096 p_fcrb->remote_busy = false;
1097 all_ok = retransmit_i_frames(
1098 p_ccb, (uint8_t)((ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >>
1099 L2CAP_FCR_REQ_SEQ_BITS_SHIFT));
1100 break;
1101 }
1102
1103 if (all_ok) {
1104 /* If polled, we need to respond with F-bit. Note, we may have sent a
1105 * I-frame with the F-bit */
1106 if (p_fcrb->send_f_rsp) {
1107 if (p_fcrb->srej_sent)
1108 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, L2CAP_FCR_F_BIT);
1109 else if (p_fcrb->local_busy)
1110 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_F_BIT);
1111 else
1112 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_F_BIT);
1113
1114 p_fcrb->send_f_rsp = false;
1115 }
1116 } else {
1117 L2CAP_TRACE_DEBUG("process_s_frame hit_max_retries");
1118 }
1119
1120 osi_free(p_buf);
1121 }
1122
1123 /*******************************************************************************
1124 *
1125 * Function process_i_frame
1126 *
1127 * Description Process an I frame
1128 *
1129 * Returns -
1130 *
1131 ******************************************************************************/
process_i_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word,bool delay_ack)1132 static void process_i_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word,
1133 bool delay_ack) {
1134 CHECK(p_ccb != NULL);
1135 CHECK(p_buf != NULL);
1136
1137 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1138 uint8_t tx_seq, num_lost, num_to_ack, next_srej;
1139
1140 /* If we were doing checkpoint recovery, first retransmit all unacked I-frames
1141 */
1142 if (ctrl_word & L2CAP_FCR_F_BIT) {
1143 if (!retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS)) {
1144 osi_free(p_buf);
1145 return;
1146 }
1147 }
1148
1149 #if (L2CAP_ERTM_STATS == TRUE)
1150 p_ccb->fcrb.ertm_pkt_counts[1]++;
1151 p_ccb->fcrb.ertm_byte_counts[1] += p_buf->len;
1152 #endif
1153
1154 /* Extract the sequence number */
1155 tx_seq = (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1156
1157 /* If we have flow controlled the peer, ignore any bad I-frames from him */
1158 if ((tx_seq != p_fcrb->next_seq_expected) && (p_fcrb->local_busy)) {
1159 L2CAP_TRACE_WARNING("Dropping bad I-Frame since we flowed off, tx_seq:%u",
1160 tx_seq);
1161 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
1162 osi_free(p_buf);
1163 return;
1164 }
1165
1166 /* Check if tx-sequence is the expected one */
1167 if (tx_seq != p_fcrb->next_seq_expected) {
1168 num_lost = (tx_seq - p_fcrb->next_seq_expected) & L2CAP_FCR_SEQ_MODULO;
1169
1170 /* Is the frame a duplicate ? If so, just drop it */
1171 if (num_lost >= p_ccb->our_cfg.fcr.tx_win_sz) {
1172 /* Duplicate - simply drop it */
1173 L2CAP_TRACE_WARNING(
1174 "process_i_frame() Dropping Duplicate Frame tx_seq:%u ExpectedTxSeq "
1175 "%u",
1176 tx_seq, p_fcrb->next_seq_expected);
1177 osi_free(p_buf);
1178 } else {
1179 L2CAP_TRACE_WARNING(
1180 "process_i_frame() CID: 0x%04x Lost: %u tx_seq:%u ExpTxSeq %u "
1181 "Rej: %u SRej: %u",
1182 p_ccb->local_cid, num_lost, tx_seq, p_fcrb->next_seq_expected,
1183 p_fcrb->rej_sent, p_fcrb->srej_sent);
1184
1185 if (p_fcrb->srej_sent) {
1186 /* If SREJ sent, save the frame for later processing as long as it is in
1187 * sequence */
1188 next_srej =
1189 (((BT_HDR*)fixed_queue_try_peek_last(p_fcrb->srej_rcv_hold_q))
1190 ->layer_specific +
1191 1) &
1192 L2CAP_FCR_SEQ_MODULO;
1193
1194 if ((tx_seq == next_srej) &&
1195 (fixed_queue_length(p_fcrb->srej_rcv_hold_q) <
1196 p_ccb->our_cfg.fcr.tx_win_sz)) {
1197 /* If user gave us a pool for held rx buffers, use that */
1198 /* TODO: Could that happen? Get rid of this code. */
1199 if (p_ccb->ertm_info.fcr_rx_buf_size != L2CAP_FCR_RX_BUF_SIZE) {
1200 BT_HDR* p_buf2;
1201
1202 /* Adjust offset and len so that control word is copied */
1203 p_buf->offset -= L2CAP_FCR_OVERHEAD;
1204 p_buf->len += L2CAP_FCR_OVERHEAD;
1205
1206 p_buf2 = l2c_fcr_clone_buf(p_buf, p_buf->offset, p_buf->len);
1207
1208 if (p_buf2) {
1209 osi_free(p_buf);
1210 p_buf = p_buf2;
1211 }
1212 p_buf->offset += L2CAP_FCR_OVERHEAD;
1213 p_buf->len -= L2CAP_FCR_OVERHEAD;
1214 }
1215 L2CAP_TRACE_DEBUG(
1216 "process_i_frame() Lost: %u tx_seq:%u ExpTxSeq %u Rej: %u "
1217 "SRej1",
1218 num_lost, tx_seq, p_fcrb->next_seq_expected, p_fcrb->rej_sent);
1219
1220 p_buf->layer_specific = tx_seq;
1221 fixed_queue_enqueue(p_fcrb->srej_rcv_hold_q, p_buf);
1222 } else {
1223 L2CAP_TRACE_WARNING(
1224 "process_i_frame() CID: 0x%04x frame dropped in Srej Sent "
1225 "next_srej:%u hold_q.count:%u win_sz:%u",
1226 p_ccb->local_cid, next_srej,
1227 fixed_queue_length(p_fcrb->srej_rcv_hold_q),
1228 p_ccb->our_cfg.fcr.tx_win_sz);
1229
1230 p_fcrb->rej_after_srej = true;
1231 osi_free(p_buf);
1232 }
1233 } else if (p_fcrb->rej_sent) {
1234 L2CAP_TRACE_WARNING(
1235 "process_i_frame() CID: 0x%04x Lost: %u tx_seq:%u ExpTxSeq %u "
1236 "Rej: 1 SRej: %u",
1237 p_ccb->local_cid, num_lost, tx_seq, p_fcrb->next_seq_expected,
1238 p_fcrb->srej_sent);
1239
1240 /* If REJ sent, just drop the frame */
1241 osi_free(p_buf);
1242 } else {
1243 L2CAP_TRACE_DEBUG(
1244 "process_i_frame() CID: 0x%04x tx_seq:%u ExpTxSeq %u Rej: %u",
1245 p_ccb->local_cid, tx_seq, p_fcrb->next_seq_expected,
1246 p_fcrb->rej_sent);
1247
1248 /* If only one lost, we will send SREJ, otherwise we will send REJ */
1249 if (num_lost > 1) {
1250 osi_free(p_buf);
1251 p_fcrb->rej_sent = true;
1252 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_REJ, 0);
1253 } else {
1254 if (!fixed_queue_is_empty(p_fcrb->srej_rcv_hold_q)) {
1255 L2CAP_TRACE_ERROR(
1256 "process_i_frame() CID: 0x%04x sending SREJ tx_seq:%d "
1257 "hold_q.count:%u",
1258 p_ccb->local_cid, tx_seq,
1259 fixed_queue_length(p_fcrb->srej_rcv_hold_q));
1260 }
1261 p_buf->layer_specific = tx_seq;
1262 fixed_queue_enqueue(p_fcrb->srej_rcv_hold_q, p_buf);
1263 p_fcrb->srej_sent = true;
1264 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, 0);
1265 }
1266 alarm_cancel(p_ccb->fcrb.ack_timer);
1267 }
1268 }
1269 return;
1270 }
1271
1272 /* Seq number is the next expected. Clear possible reject exception in case it
1273 * occured */
1274 p_fcrb->rej_sent = p_fcrb->srej_sent = false;
1275
1276 /* Adjust the next_seq, so that if the upper layer sends more data in the
1277 callback
1278 context, the received frame is acked by an I-frame. */
1279 p_fcrb->next_seq_expected = (tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
1280
1281 /* If any SAR problem in eRTM mode, spec says disconnect. */
1282 if (!do_sar_reassembly(p_ccb, p_buf, ctrl_word)) {
1283 L2CAP_TRACE_WARNING("process_i_frame() CID: 0x%04x reassembly failed",
1284 p_ccb->local_cid);
1285 l2cu_disconnect_chnl(p_ccb);
1286 return;
1287 }
1288
1289 /* RR optimization - if peer can still send us more, then start an ACK timer
1290 */
1291 num_to_ack = (p_fcrb->next_seq_expected - p_fcrb->last_ack_sent) &
1292 L2CAP_FCR_SEQ_MODULO;
1293
1294 if ((num_to_ack < p_ccb->fcrb.max_held_acks) && (!p_fcrb->local_busy))
1295 delay_ack = true;
1296
1297 /* We should neve never ack frame if we are not in OPEN state */
1298 if ((num_to_ack != 0) && p_ccb->in_use && (p_ccb->chnl_state == CST_OPEN)) {
1299 /* If no frames are awaiting transmission or are held, send an RR or RNR
1300 * S-frame for ack */
1301 if (delay_ack) {
1302 /* If it is the first I frame we did not ack, start ack timer */
1303 if (!alarm_is_scheduled(p_ccb->fcrb.ack_timer)) {
1304 alarm_set_on_queue(p_ccb->fcrb.ack_timer, L2CAP_FCR_ACK_TIMEOUT_MS,
1305 l2c_fcrb_ack_timer_timeout, p_ccb,
1306 btu_general_alarm_queue);
1307 }
1308 } else if ((fixed_queue_is_empty(p_ccb->xmit_hold_q) ||
1309 l2c_fcr_is_flow_controlled(p_ccb)) &&
1310 fixed_queue_is_empty(p_ccb->fcrb.srej_rcv_hold_q)) {
1311 if (p_fcrb->local_busy)
1312 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
1313 else
1314 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
1315 }
1316 }
1317 }
1318
1319 /*******************************************************************************
1320 *
1321 * Function process_stream_frame
1322 *
1323 * Description This function processes frames in streaming mode
1324 *
1325 * Returns -
1326 *
1327 ******************************************************************************/
process_stream_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf)1328 static void process_stream_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
1329 CHECK(p_ccb != NULL);
1330 CHECK(p_buf != NULL);
1331
1332 uint16_t ctrl_word;
1333 uint16_t fcs;
1334 uint8_t* p;
1335 uint8_t tx_seq;
1336
1337 /* Verify FCS if using */
1338 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
1339 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len - L2CAP_FCS_LEN;
1340
1341 /* Extract and drop the FCS from the packet */
1342 STREAM_TO_UINT16(fcs, p);
1343 p_buf->len -= L2CAP_FCS_LEN;
1344
1345 if (l2c_fcr_rx_get_fcs(p_buf) != fcs) {
1346 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x BAD FCS",
1347 p_ccb->local_cid);
1348 osi_free(p_buf);
1349 return;
1350 }
1351 }
1352
1353 /* Get the control word */
1354 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
1355
1356 STREAM_TO_UINT16(ctrl_word, p);
1357
1358 p_buf->len -= L2CAP_FCR_OVERHEAD;
1359 p_buf->offset += L2CAP_FCR_OVERHEAD;
1360
1361 /* Make sure it is an I-frame */
1362 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) {
1363 L2CAP_TRACE_WARNING(
1364 "Rx L2CAP PDU: CID: 0x%04x BAD S-frame in streaming mode ctrl_word: "
1365 "0x%04x",
1366 p_ccb->local_cid, ctrl_word);
1367 osi_free(p_buf);
1368 return;
1369 }
1370
1371 L2CAP_TRACE_EVENT(
1372 "L2CAP eRTM Rx I-frame: cid: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
1373 "ReqSeq: %u F: %u",
1374 p_ccb->local_cid, p_buf->len,
1375 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
1376 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
1377 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
1378 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
1379
1380 /* Extract the sequence number */
1381 tx_seq = (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1382
1383 /* Check if tx-sequence is the expected one */
1384 if (tx_seq != p_ccb->fcrb.next_seq_expected) {
1385 L2CAP_TRACE_WARNING(
1386 "Rx L2CAP PDU: CID: 0x%04x Lost frames Exp: %u Got: %u p_rx_sdu: "
1387 "0x%08x",
1388 p_ccb->local_cid, p_ccb->fcrb.next_seq_expected, tx_seq,
1389 p_ccb->fcrb.p_rx_sdu);
1390
1391 /* Lost one or more packets, so flush the SAR queue */
1392 osi_free_and_reset((void**)&p_ccb->fcrb.p_rx_sdu);
1393 }
1394
1395 p_ccb->fcrb.next_seq_expected = (tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
1396
1397 if (!do_sar_reassembly(p_ccb, p_buf, ctrl_word)) {
1398 /* Some sort of SAR error, so flush the SAR queue */
1399 osi_free_and_reset((void**)&p_ccb->fcrb.p_rx_sdu);
1400 }
1401 }
1402
1403 /*******************************************************************************
1404 *
1405 * Function do_sar_reassembly
1406 *
1407 * Description Process SAR bits and re-assemble frame
1408 *
1409 * Returns true if all OK, else false
1410 *
1411 ******************************************************************************/
do_sar_reassembly(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word)1412 static bool do_sar_reassembly(tL2C_CCB* p_ccb, BT_HDR* p_buf,
1413 uint16_t ctrl_word) {
1414 CHECK(p_ccb != NULL);
1415 CHECK(p_buf != NULL);
1416
1417 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1418 uint16_t sar_type = ctrl_word & L2CAP_FCR_SEG_BITS;
1419 bool packet_ok = true;
1420 uint8_t* p;
1421
1422 /* Check if the SAR state is correct */
1423 if ((sar_type == L2CAP_FCR_UNSEG_SDU) || (sar_type == L2CAP_FCR_START_SDU)) {
1424 if (p_fcrb->p_rx_sdu != NULL) {
1425 L2CAP_TRACE_WARNING(
1426 "SAR - got unexpected unsegmented or start SDU Expected len: %u "
1427 "Got so far: %u",
1428 p_fcrb->rx_sdu_len, p_fcrb->p_rx_sdu->len);
1429
1430 packet_ok = false;
1431 }
1432 /* Check the length of the packet */
1433 if ((sar_type == L2CAP_FCR_START_SDU) &&
1434 (p_buf->len < L2CAP_SDU_LEN_OVERHEAD)) {
1435 L2CAP_TRACE_WARNING("SAR start packet too short: %u", p_buf->len);
1436 packet_ok = false;
1437 }
1438 } else {
1439 if (p_fcrb->p_rx_sdu == NULL) {
1440 L2CAP_TRACE_WARNING("SAR - got unexpected cont or end SDU");
1441 packet_ok = false;
1442 }
1443 }
1444
1445 if ((packet_ok) && (sar_type != L2CAP_FCR_UNSEG_SDU)) {
1446 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
1447
1448 /* For start SDU packet, extract the SDU length */
1449 if (sar_type == L2CAP_FCR_START_SDU) {
1450 /* Get the SDU length */
1451 STREAM_TO_UINT16(p_fcrb->rx_sdu_len, p);
1452 p_buf->offset += 2;
1453 p_buf->len -= 2;
1454
1455 if (p_fcrb->rx_sdu_len > p_ccb->max_rx_mtu) {
1456 L2CAP_TRACE_WARNING("SAR - SDU len: %u larger than MTU: %u",
1457 p_fcrb->rx_sdu_len, p_fcrb->rx_sdu_len);
1458 packet_ok = false;
1459 } else {
1460 p_fcrb->p_rx_sdu = (BT_HDR*)osi_malloc(L2CAP_MAX_BUF_SIZE);
1461 p_fcrb->p_rx_sdu->offset = OBX_BUF_MIN_OFFSET;
1462 p_fcrb->p_rx_sdu->len = 0;
1463 }
1464 }
1465
1466 if (packet_ok) {
1467 if ((p_fcrb->p_rx_sdu->len + p_buf->len) > p_fcrb->rx_sdu_len) {
1468 L2CAP_TRACE_ERROR(
1469 "SAR - SDU len exceeded Type: %u Lengths: %u %u %u", sar_type,
1470 p_fcrb->p_rx_sdu->len, p_buf->len, p_fcrb->rx_sdu_len);
1471 packet_ok = false;
1472 } else if ((sar_type == L2CAP_FCR_END_SDU) &&
1473 ((p_fcrb->p_rx_sdu->len + p_buf->len) != p_fcrb->rx_sdu_len)) {
1474 L2CAP_TRACE_WARNING("SAR - SDU end rcvd but SDU incomplete: %u %u %u",
1475 p_fcrb->p_rx_sdu->len, p_buf->len,
1476 p_fcrb->rx_sdu_len);
1477 packet_ok = false;
1478 } else {
1479 memcpy(((uint8_t*)(p_fcrb->p_rx_sdu + 1)) + p_fcrb->p_rx_sdu->offset +
1480 p_fcrb->p_rx_sdu->len,
1481 p, p_buf->len);
1482
1483 p_fcrb->p_rx_sdu->len += p_buf->len;
1484
1485 osi_free(p_buf);
1486 p_buf = NULL;
1487
1488 if (sar_type == L2CAP_FCR_END_SDU) {
1489 p_buf = p_fcrb->p_rx_sdu;
1490 p_fcrb->p_rx_sdu = NULL;
1491 }
1492 }
1493 }
1494 }
1495
1496 if (packet_ok == false) {
1497 osi_free(p_buf);
1498 } else if (p_buf != NULL) {
1499 #if (L2CAP_NUM_FIXED_CHNLS > 0)
1500 if (p_ccb->local_cid < L2CAP_BASE_APPL_CID &&
1501 (p_ccb->local_cid >= L2CAP_FIRST_FIXED_CHNL &&
1502 p_ccb->local_cid <= L2CAP_LAST_FIXED_CHNL)) {
1503 if (l2cb.fixed_reg[p_ccb->local_cid - L2CAP_FIRST_FIXED_CHNL]
1504 .pL2CA_FixedData_Cb)
1505 (*l2cb.fixed_reg[p_ccb->local_cid - L2CAP_FIRST_FIXED_CHNL]
1506 .pL2CA_FixedData_Cb)(p_ccb->local_cid,
1507 p_ccb->p_lcb->remote_bd_addr, p_buf);
1508 } else
1509 #endif
1510 l2c_csm_execute(p_ccb, L2CEVT_L2CAP_DATA, p_buf);
1511 }
1512
1513 return (packet_ok);
1514 }
1515
1516 /*******************************************************************************
1517 *
1518 * Function retransmit_i_frames
1519 *
1520 * Description This function retransmits i-frames awaiting acks.
1521 *
1522 * Returns bool - true if retransmitted
1523 *
1524 ******************************************************************************/
retransmit_i_frames(tL2C_CCB * p_ccb,uint8_t tx_seq)1525 static bool retransmit_i_frames(tL2C_CCB* p_ccb, uint8_t tx_seq) {
1526 CHECK(p_ccb != NULL);
1527
1528 BT_HDR* p_buf = NULL;
1529 uint8_t* p;
1530 uint8_t buf_seq;
1531 uint16_t ctrl_word;
1532
1533 if ((!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q)) &&
1534 (p_ccb->peer_cfg.fcr.max_transmit != 0) &&
1535 (p_ccb->fcrb.num_tries >= p_ccb->peer_cfg.fcr.max_transmit)) {
1536 L2CAP_TRACE_EVENT(
1537 "Max Tries Exceeded: (last_acq: %d CID: 0x%04x num_tries: %u (max: "
1538 "%u) ack_q_count: %u",
1539 p_ccb->fcrb.last_rx_ack, p_ccb->local_cid, p_ccb->fcrb.num_tries,
1540 p_ccb->peer_cfg.fcr.max_transmit,
1541 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
1542
1543 l2cu_disconnect_chnl(p_ccb);
1544 return (false);
1545 }
1546
1547 /* tx_seq indicates whether to retransmit a specific sequence or all (if ==
1548 * L2C_FCR_RETX_ALL_PKTS) */
1549 list_t* list_ack = NULL;
1550 const list_node_t* node_ack = NULL;
1551 if (!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q)) {
1552 list_ack = fixed_queue_get_list(p_ccb->fcrb.waiting_for_ack_q);
1553 node_ack = list_begin(list_ack);
1554 }
1555 if (tx_seq != L2C_FCR_RETX_ALL_PKTS) {
1556 /* If sending only one, the sequence number tells us which one. Look for it.
1557 */
1558 if (list_ack != NULL) {
1559 for (; node_ack != list_end(list_ack); node_ack = list_next(node_ack)) {
1560 p_buf = (BT_HDR*)list_node(node_ack);
1561 /* Get the old control word */
1562 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
1563
1564 STREAM_TO_UINT16(ctrl_word, p);
1565
1566 buf_seq =
1567 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1568
1569 L2CAP_TRACE_DEBUG(
1570 "retransmit_i_frames() cur seq: %u looking for: %u", buf_seq,
1571 tx_seq);
1572
1573 if (tx_seq == buf_seq) break;
1574 }
1575 }
1576
1577 if (!p_buf) {
1578 L2CAP_TRACE_ERROR("retransmit_i_frames() UNKNOWN seq: %u q_count: %u",
1579 tx_seq,
1580 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
1581 return (true);
1582 }
1583 } else {
1584 // Iterate though list and flush the amount requested from
1585 // the transmit data queue that satisfy the layer and event conditions.
1586 for (list_node_t* node_tmp = list_begin(p_ccb->p_lcb->link_xmit_data_q);
1587 node_tmp != list_end(p_ccb->p_lcb->link_xmit_data_q);) {
1588 BT_HDR* p_tmp = (BT_HDR*)list_node(node_tmp);
1589 node_tmp = list_next(node_tmp);
1590
1591 /* Do not flush other CIDs or partial segments */
1592 if ((p_tmp->layer_specific == 0) && (p_tmp->event == p_ccb->local_cid)) {
1593 list_remove(p_ccb->p_lcb->link_xmit_data_q, p_tmp);
1594 osi_free(p_tmp);
1595 }
1596 }
1597
1598 /* Also flush our retransmission queue */
1599 while (!fixed_queue_is_empty(p_ccb->fcrb.retrans_q))
1600 osi_free(fixed_queue_try_dequeue(p_ccb->fcrb.retrans_q));
1601
1602 if (list_ack != NULL) node_ack = list_begin(list_ack);
1603 }
1604
1605 if (list_ack != NULL) {
1606 while (node_ack != list_end(list_ack)) {
1607 p_buf = (BT_HDR*)list_node(node_ack);
1608 node_ack = list_next(node_ack);
1609
1610 BT_HDR* p_buf2 = l2c_fcr_clone_buf(p_buf, p_buf->offset, p_buf->len);
1611 if (p_buf2) {
1612 p_buf2->layer_specific = p_buf->layer_specific;
1613
1614 fixed_queue_enqueue(p_ccb->fcrb.retrans_q, p_buf2);
1615 }
1616
1617 if ((tx_seq != L2C_FCR_RETX_ALL_PKTS) || (p_buf2 == NULL)) break;
1618 }
1619 }
1620
1621 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, NULL);
1622
1623 if (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q)) {
1624 p_ccb->fcrb.num_tries++;
1625 l2c_fcr_start_timer(p_ccb);
1626 }
1627
1628 return (true);
1629 }
1630
1631 /*******************************************************************************
1632 *
1633 * Function l2c_fcr_get_next_xmit_sdu_seg
1634 *
1635 * Description Get the next SDU segment to transmit.
1636 *
1637 * Returns pointer to buffer with segment or NULL
1638 *
1639 ******************************************************************************/
l2c_fcr_get_next_xmit_sdu_seg(tL2C_CCB * p_ccb,uint16_t max_packet_length)1640 BT_HDR* l2c_fcr_get_next_xmit_sdu_seg(tL2C_CCB* p_ccb,
1641 uint16_t max_packet_length) {
1642 CHECK(p_ccb != NULL);
1643
1644 bool first_seg = false, /* The segment is the first part of data */
1645 mid_seg = false, /* The segment is the middle part of data */
1646 last_seg = false; /* The segment is the last part of data */
1647 uint16_t sdu_len = 0;
1648 BT_HDR *p_buf, *p_xmit;
1649 uint8_t* p;
1650 uint16_t max_pdu = p_ccb->tx_mps /* Needed? - L2CAP_MAX_HEADER_FCS*/;
1651
1652 /* If there is anything in the retransmit queue, that goes first
1653 */
1654 p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->fcrb.retrans_q);
1655 if (p_buf != NULL) {
1656 /* Update Rx Seq and FCS if we acked some packets while this one was queued
1657 */
1658 prepare_I_frame(p_ccb, p_buf, true);
1659
1660 p_buf->event = p_ccb->local_cid;
1661
1662 #if (L2CAP_ERTM_STATS == TRUE)
1663 p_ccb->fcrb.pkts_retransmitted++;
1664 p_ccb->fcrb.ertm_pkt_counts[0]++;
1665 p_ccb->fcrb.ertm_byte_counts[0] += (p_buf->len - 8);
1666 #endif
1667 return (p_buf);
1668 }
1669
1670 /* For BD/EDR controller, max_packet_length is set to 0 */
1671 /* For AMP controller, max_packet_length is set by available blocks */
1672 if ((max_packet_length > L2CAP_MAX_HEADER_FCS) &&
1673 (max_pdu + L2CAP_MAX_HEADER_FCS > max_packet_length)) {
1674 max_pdu = max_packet_length - L2CAP_MAX_HEADER_FCS;
1675 }
1676
1677 p_buf = (BT_HDR*)fixed_queue_try_peek_first(p_ccb->xmit_hold_q);
1678
1679 /* If there is more data than the MPS, it requires segmentation */
1680 if (p_buf->len > max_pdu) {
1681 /* We are using the "event" field to tell is if we already started
1682 * segmentation */
1683 if (p_buf->event == 0) {
1684 first_seg = true;
1685 sdu_len = p_buf->len;
1686 } else
1687 mid_seg = true;
1688
1689 /* Get a new buffer and copy the data that can be sent in a PDU */
1690 p_xmit = l2c_fcr_clone_buf(p_buf, L2CAP_MIN_OFFSET + L2CAP_SDU_LEN_OFFSET,
1691 max_pdu);
1692
1693 if (p_xmit != NULL) {
1694 p_buf->event = p_ccb->local_cid;
1695 p_xmit->event = p_ccb->local_cid;
1696
1697 p_buf->len -= max_pdu;
1698 p_buf->offset += max_pdu;
1699
1700 /* copy PBF setting */
1701 p_xmit->layer_specific = p_buf->layer_specific;
1702 } else /* Should never happen if the application has configured buffers
1703 correctly */
1704 {
1705 L2CAP_TRACE_ERROR(
1706 "L2CAP - cannot get buffer for segmentation, max_pdu: %u", max_pdu);
1707 return (NULL);
1708 }
1709 } else /* Use the original buffer if no segmentation, or the last segment */
1710 {
1711 p_xmit = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q);
1712
1713 if (p_xmit->event != 0) last_seg = true;
1714
1715 p_xmit->event = p_ccb->local_cid;
1716 }
1717
1718 /* Step back to add the L2CAP headers */
1719 p_xmit->offset -= (L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD);
1720 p_xmit->len += L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD;
1721
1722 if (first_seg) {
1723 p_xmit->offset -= L2CAP_SDU_LEN_OVERHEAD;
1724 p_xmit->len += L2CAP_SDU_LEN_OVERHEAD;
1725 }
1726
1727 /* Set the pointer to the beginning of the data */
1728 p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1729
1730 /* Now the L2CAP header */
1731
1732 /* Note: if FCS has to be included then the length is recalculated later */
1733 UINT16_TO_STREAM(p, p_xmit->len - L2CAP_PKT_OVERHEAD);
1734
1735 UINT16_TO_STREAM(p, p_ccb->remote_cid);
1736
1737 if (first_seg) {
1738 /* Skip control word and add SDU length */
1739 p += 2;
1740 UINT16_TO_STREAM(p, sdu_len);
1741
1742 /* We will store the SAR type in layer-specific */
1743 /* layer_specific is shared with flushable flag(bits 0-1), don't clear it */
1744 p_xmit->layer_specific |= L2CAP_FCR_START_SDU;
1745
1746 first_seg = false;
1747 } else if (mid_seg)
1748 p_xmit->layer_specific |= L2CAP_FCR_CONT_SDU;
1749 else if (last_seg)
1750 p_xmit->layer_specific |= L2CAP_FCR_END_SDU;
1751 else
1752 p_xmit->layer_specific |= L2CAP_FCR_UNSEG_SDU;
1753
1754 prepare_I_frame(p_ccb, p_xmit, false);
1755
1756 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
1757 BT_HDR* p_wack =
1758 l2c_fcr_clone_buf(p_xmit, HCI_DATA_PREAMBLE_SIZE, p_xmit->len);
1759
1760 if (!p_wack) {
1761 L2CAP_TRACE_ERROR(
1762 "L2CAP - no buffer for xmit cloning, CID: 0x%04x Length: %u",
1763 p_ccb->local_cid, p_xmit->len);
1764
1765 /* We will not save the FCS in case we reconfigure and change options */
1766 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) p_xmit->len -= L2CAP_FCS_LEN;
1767
1768 /* Pretend we sent it and it got lost */
1769 fixed_queue_enqueue(p_ccb->fcrb.waiting_for_ack_q, p_xmit);
1770 return (NULL);
1771 } else {
1772 #if (L2CAP_ERTM_STATS == TRUE)
1773 /* set timestamp at the end of tx I-frame to get acking delay */
1774 /*
1775 * NOTE: Here we assume the allocate buffer is large enough
1776 * to include extra 4 octets at the end.
1777 */
1778 p = ((uint8_t*)(p_wack + 1)) + p_wack->offset + p_wack->len;
1779 UINT32_TO_STREAM(p, time_get_os_boottime_ms());
1780 #endif
1781 /* We will not save the FCS in case we reconfigure and change options */
1782 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) p_wack->len -= L2CAP_FCS_LEN;
1783
1784 p_wack->layer_specific = p_xmit->layer_specific;
1785 fixed_queue_enqueue(p_ccb->fcrb.waiting_for_ack_q, p_wack);
1786 }
1787
1788 #if (L2CAP_ERTM_STATS == TRUE)
1789 p_ccb->fcrb.ertm_pkt_counts[0]++;
1790 p_ccb->fcrb.ertm_byte_counts[0] += (p_xmit->len - 8);
1791 #endif
1792 }
1793
1794 return (p_xmit);
1795 }
1796
1797 /*******************************************************************************
1798 *
1799 * Function l2c_lcc_get_next_xmit_sdu_seg
1800 *
1801 * Description Get the next SDU segment to transmit for LE connection
1802 * oriented channel
1803 *
1804 * Returns pointer to buffer with segment or NULL
1805 *
1806 ******************************************************************************/
l2c_lcc_get_next_xmit_sdu_seg(tL2C_CCB * p_ccb,uint16_t max_packet_length)1807 BT_HDR* l2c_lcc_get_next_xmit_sdu_seg(tL2C_CCB* p_ccb,
1808 uint16_t max_packet_length) {
1809 bool first_seg = false; /* The segment is the first part of data */
1810 bool last_seg = false; /* The segment is the last part of data */
1811 uint16_t no_of_bytes_to_send = 0;
1812 uint16_t sdu_len = 0;
1813 BT_HDR *p_buf, *p_xmit;
1814 uint8_t* p;
1815 uint16_t max_pdu = p_ccb->peer_conn_cfg.mps;
1816
1817 p_buf = (BT_HDR*)fixed_queue_try_peek_first(p_ccb->xmit_hold_q);
1818
1819 /* We are using the "event" field to tell is if we already started
1820 * segmentation */
1821 if (p_buf->event == 0) {
1822 first_seg = true;
1823 sdu_len = p_buf->len;
1824 if (p_buf->len <= (max_pdu - L2CAP_LCC_SDU_LENGTH)) {
1825 last_seg = true;
1826 no_of_bytes_to_send = p_buf->len;
1827 } else
1828 no_of_bytes_to_send = max_pdu - L2CAP_LCC_SDU_LENGTH;
1829 } else if (p_buf->len <= max_pdu) {
1830 last_seg = true;
1831 no_of_bytes_to_send = p_buf->len;
1832 } else {
1833 /* Middle Packet */
1834 no_of_bytes_to_send = max_pdu;
1835 }
1836
1837 /* Get a new buffer and copy the data that can be sent in a PDU */
1838 if (first_seg == true)
1839 p_xmit = l2c_fcr_clone_buf(p_buf, L2CAP_LCC_OFFSET, no_of_bytes_to_send);
1840 else
1841 p_xmit = l2c_fcr_clone_buf(p_buf, L2CAP_MIN_OFFSET, no_of_bytes_to_send);
1842
1843 if (p_xmit != NULL) {
1844 p_buf->event = p_ccb->local_cid;
1845 p_xmit->event = p_ccb->local_cid;
1846
1847 if (first_seg == true) {
1848 p_xmit->offset -= L2CAP_LCC_SDU_LENGTH; /* for writing the SDU length. */
1849 p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1850 UINT16_TO_STREAM(p, sdu_len);
1851 p_xmit->len += L2CAP_LCC_SDU_LENGTH;
1852 }
1853
1854 p_buf->len -= no_of_bytes_to_send;
1855 p_buf->offset += no_of_bytes_to_send;
1856
1857 /* copy PBF setting */
1858 p_xmit->layer_specific = p_buf->layer_specific;
1859
1860 } else /* Should never happen if the application has configured buffers
1861 correctly */
1862 {
1863 L2CAP_TRACE_ERROR("L2CAP - cannot get buffer, for segmentation");
1864 return (NULL);
1865 }
1866
1867 if (last_seg == true) {
1868 p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q);
1869 osi_free(p_buf);
1870 }
1871
1872 /* Step back to add the L2CAP headers */
1873 p_xmit->offset -= L2CAP_PKT_OVERHEAD;
1874 p_xmit->len += L2CAP_PKT_OVERHEAD;
1875
1876 /* Set the pointer to the beginning of the data */
1877 p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1878
1879 /* Note: if FCS has to be included then the length is recalculated later */
1880 UINT16_TO_STREAM(p, p_xmit->len - L2CAP_PKT_OVERHEAD);
1881 UINT16_TO_STREAM(p, p_ccb->remote_cid);
1882 return (p_xmit);
1883 }
1884
1885 /*******************************************************************************
1886 * Configuration negotiation functions
1887 *
1888 * The following functions are used in negotiating channel modes during
1889 * configuration
1890 ******************************************************************************/
1891
1892 /*******************************************************************************
1893 *
1894 * Function l2c_fcr_chk_chan_modes
1895 *
1896 * Description Validates and adjusts if necessary, the FCR options
1897 * based on remote EXT features.
1898 *
1899 * Note: This assumes peer EXT Features have been received.
1900 * Basic mode is used if FCR Options have not been received
1901 *
1902 * Returns uint8_t - nonzero if can continue, '0' if no compatible
1903 * channels
1904 *
1905 ******************************************************************************/
l2c_fcr_chk_chan_modes(tL2C_CCB * p_ccb)1906 uint8_t l2c_fcr_chk_chan_modes(tL2C_CCB* p_ccb) {
1907 CHECK(p_ccb != NULL);
1908
1909 /* Remove nonbasic options that the peer does not support */
1910 if (!(p_ccb->p_lcb->peer_ext_fea & L2CAP_EXTFEA_ENH_RETRANS))
1911 p_ccb->ertm_info.allowed_modes &= ~L2CAP_FCR_CHAN_OPT_ERTM;
1912
1913 if (!(p_ccb->p_lcb->peer_ext_fea & L2CAP_EXTFEA_STREAM_MODE))
1914 p_ccb->ertm_info.allowed_modes &= ~L2CAP_FCR_CHAN_OPT_STREAM;
1915
1916 /* At least one type needs to be set (Basic, ERTM, STM) to continue */
1917 if (!p_ccb->ertm_info.allowed_modes) {
1918 L2CAP_TRACE_WARNING(
1919 "L2CAP - Peer does not support our desired channel types");
1920 }
1921
1922 return (p_ccb->ertm_info.allowed_modes);
1923 }
1924
1925 /*******************************************************************************
1926 *
1927 * Function l2c_fcr_adj_our_req_options
1928 *
1929 * Description Validates and sets up the FCR options passed in from
1930 * L2CA_ConfigReq based on remote device's features.
1931 *
1932 * Returns true if no errors, Otherwise false
1933 *
1934 ******************************************************************************/
l2c_fcr_adj_our_req_options(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)1935 bool l2c_fcr_adj_our_req_options(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
1936 CHECK(p_ccb != NULL);
1937 CHECK(p_cfg != NULL);
1938
1939 tL2CAP_FCR_OPTS* p_fcr = &p_cfg->fcr;
1940
1941 if (p_fcr->mode != p_ccb->ertm_info.preferred_mode) {
1942 L2CAP_TRACE_WARNING(
1943 "l2c_fcr_adj_our_req_options - preferred_mode (%d), does not match "
1944 "mode (%d)",
1945 p_ccb->ertm_info.preferred_mode, p_fcr->mode);
1946
1947 /* The preferred mode is passed in through tL2CAP_ERTM_INFO, so override
1948 * this one */
1949 p_fcr->mode = p_ccb->ertm_info.preferred_mode;
1950 }
1951
1952 /* If upper layer did not request eRTM mode, BASIC must be used */
1953 if (p_ccb->ertm_info.allowed_modes == L2CAP_FCR_CHAN_OPT_BASIC) {
1954 if (p_cfg->fcr_present && p_fcr->mode != L2CAP_FCR_BASIC_MODE) {
1955 L2CAP_TRACE_WARNING(
1956 "l2c_fcr_adj_our_req_options (mode %d): ERROR: No FCR options set "
1957 "using BASIC mode",
1958 p_fcr->mode);
1959 }
1960 p_fcr->mode = L2CAP_FCR_BASIC_MODE;
1961 }
1962
1963 /* Process the FCR options if initial channel bring-up (not a reconfig
1964 *request)
1965 ** Determine initial channel mode to try based on our options and remote's
1966 *features
1967 */
1968 if (p_cfg->fcr_present && !(p_ccb->config_done & RECONFIG_FLAG)) {
1969 /* We need to have at least one mode type common with the peer */
1970 if (!l2c_fcr_chk_chan_modes(p_ccb)) {
1971 /* Two channels have incompatible supported types */
1972 l2cu_disconnect_chnl(p_ccb);
1973 return (false);
1974 }
1975
1976 /* Basic is the only common channel mode between the two devices */
1977 else if (p_ccb->ertm_info.allowed_modes == L2CAP_FCR_CHAN_OPT_BASIC) {
1978 /* We only want to try Basic, so bypass sending the FCR options entirely
1979 */
1980 p_cfg->fcr_present = false;
1981 p_cfg->fcs_present = false; /* Illegal to use FCS option in basic mode */
1982 p_cfg->ext_flow_spec_present =
1983 false; /* Illegal to use extended flow spec in basic mode */
1984 }
1985
1986 /* We have at least one non-basic mode available
1987 * Override mode from available mode options based on preference, if needed
1988 */
1989 else {
1990 /* If peer does not support STREAMING, try ERTM */
1991 if (p_fcr->mode == L2CAP_FCR_STREAM_MODE &&
1992 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_STREAM)) {
1993 L2CAP_TRACE_DEBUG(
1994 "L2C CFG: mode is STREAM, but peer does not support; Try ERTM");
1995 p_fcr->mode = L2CAP_FCR_ERTM_MODE;
1996 }
1997
1998 /* If peer does not support ERTM, try BASIC (will support this if made it
1999 * here in the code) */
2000 if (p_fcr->mode == L2CAP_FCR_ERTM_MODE &&
2001 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
2002 L2CAP_TRACE_DEBUG(
2003 "L2C CFG: mode is ERTM, but peer does not support; Try BASIC");
2004 p_fcr->mode = L2CAP_FCR_BASIC_MODE;
2005 }
2006 }
2007
2008 if (p_fcr->mode != L2CAP_FCR_BASIC_MODE) {
2009 /* MTU must be smaller than buffer size */
2010 if ((p_cfg->mtu_present) && (p_cfg->mtu > p_ccb->max_rx_mtu)) {
2011 L2CAP_TRACE_WARNING("L2CAP - MTU: %u larger than buf size: %u",
2012 p_cfg->mtu, p_ccb->max_rx_mtu);
2013 return (false);
2014 }
2015
2016 /* application want to use the default MPS */
2017 if (p_fcr->mps == L2CAP_DEFAULT_ERM_MPS) {
2018 p_fcr->mps = L2CAP_MPS_OVER_BR_EDR;
2019 }
2020 /* MPS must be less than MTU */
2021 else if (p_fcr->mps > p_ccb->max_rx_mtu) {
2022 L2CAP_TRACE_WARNING("L2CAP - MPS %u invalid MTU: %u", p_fcr->mps,
2023 p_ccb->max_rx_mtu);
2024 return (false);
2025 }
2026
2027 /* We always initially read into the HCI buffer pool, so make sure it fits
2028 */
2029 if (p_fcr->mps > (L2CAP_MTU_SIZE - L2CAP_MAX_HEADER_FCS))
2030 p_fcr->mps = L2CAP_MTU_SIZE - L2CAP_MAX_HEADER_FCS;
2031 } else {
2032 p_cfg->fcs_present = false; /* Illegal to use FCS option in basic mode */
2033 p_cfg->ext_flow_spec_present =
2034 false; /* Illegal to use extended flow spec in basic mode */
2035 }
2036
2037 p_ccb->our_cfg.fcr = *p_fcr;
2038 } else /* Not sure how to send a reconfiguration(??) should fcr be included?
2039 */
2040 {
2041 p_ccb->our_cfg.fcr_present = false;
2042 }
2043
2044 return (true);
2045 }
2046
2047 /*******************************************************************************
2048 *
2049 * Function l2c_fcr_adj_monitor_retran_timeout
2050 *
2051 * Description Overrides monitor/retrans timer value based on controller
2052 *
2053 * Returns None
2054 *
2055 ******************************************************************************/
l2c_fcr_adj_monitor_retran_timeout(tL2C_CCB * p_ccb)2056 void l2c_fcr_adj_monitor_retran_timeout(tL2C_CCB* p_ccb) {
2057 CHECK(p_ccb != NULL);
2058
2059 /* adjust our monitor/retran timeout */
2060 if (p_ccb->out_cfg_fcr_present) {
2061 /*
2062 ** if we requestd ERTM or accepted ERTM
2063 ** We may accept ERTM even if we didn't request ERTM, in case of requesting
2064 *STREAM
2065 */
2066 if ((p_ccb->our_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) ||
2067 (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)) {
2068 /* upper layer setting is ignored */
2069 p_ccb->our_cfg.fcr.mon_tout = L2CAP_MIN_MONITOR_TOUT;
2070 p_ccb->our_cfg.fcr.rtrans_tout = L2CAP_MIN_RETRANS_TOUT;
2071 } else {
2072 p_ccb->our_cfg.fcr.mon_tout = 0;
2073 p_ccb->our_cfg.fcr.rtrans_tout = 0;
2074 }
2075
2076 L2CAP_TRACE_DEBUG(
2077 "l2c_fcr_adj_monitor_retran_timeout: mon_tout:%d, rtrans_tout:%d",
2078 p_ccb->our_cfg.fcr.mon_tout, p_ccb->our_cfg.fcr.rtrans_tout);
2079 }
2080 }
2081 /*******************************************************************************
2082 *
2083 * Function l2c_fcr_adj_our_rsp_options
2084 *
2085 * Description Overrides any neccesary FCR options passed in from
2086 * L2CA_ConfigRsp based on our FCR options.
2087 * Only makes adjustments if channel is in ERTM mode.
2088 *
2089 * Returns None
2090 *
2091 ******************************************************************************/
l2c_fcr_adj_our_rsp_options(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2092 void l2c_fcr_adj_our_rsp_options(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2093 CHECK(p_ccb != NULL);
2094 CHECK(p_cfg != NULL);
2095
2096 /* adjust our monitor/retran timeout */
2097 l2c_fcr_adj_monitor_retran_timeout(p_ccb);
2098
2099 p_cfg->fcr_present = p_ccb->out_cfg_fcr_present;
2100
2101 if (p_cfg->fcr_present) {
2102 /* Temporary - until a better algorithm is implemented */
2103 /* If peer's tx_wnd_sz requires too many buffers for us to support, then
2104 * adjust it. For now, respond with our own tx_wnd_sz. */
2105 /* Note: peer is not guaranteed to obey our adjustment */
2106 if (p_ccb->peer_cfg.fcr.tx_win_sz > p_ccb->our_cfg.fcr.tx_win_sz) {
2107 L2CAP_TRACE_DEBUG("%s: adjusting requested tx_win_sz from %i to %i",
2108 __func__, p_ccb->peer_cfg.fcr.tx_win_sz,
2109 p_ccb->our_cfg.fcr.tx_win_sz);
2110 p_ccb->peer_cfg.fcr.tx_win_sz = p_ccb->our_cfg.fcr.tx_win_sz;
2111 }
2112
2113 p_cfg->fcr.mode = p_ccb->peer_cfg.fcr.mode;
2114 p_cfg->fcr.tx_win_sz = p_ccb->peer_cfg.fcr.tx_win_sz;
2115 p_cfg->fcr.max_transmit = p_ccb->peer_cfg.fcr.max_transmit;
2116 p_cfg->fcr.mps = p_ccb->peer_cfg.fcr.mps;
2117 p_cfg->fcr.rtrans_tout = p_ccb->our_cfg.fcr.rtrans_tout;
2118 p_cfg->fcr.mon_tout = p_ccb->our_cfg.fcr.mon_tout;
2119 }
2120 }
2121
2122 /*******************************************************************************
2123 *
2124 * Function l2c_fcr_renegotiate_chan
2125 *
2126 * Description Called upon unsuccessful peer response to config request.
2127 * If the error is because of the channel mode, it will try
2128 * to resend using another supported optional channel.
2129 *
2130 * Returns true if resent configuration, False if channel matches or
2131 * cannot match.
2132 *
2133 ******************************************************************************/
l2c_fcr_renegotiate_chan(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2134 bool l2c_fcr_renegotiate_chan(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2135 CHECK(p_ccb != NULL);
2136 CHECK(p_cfg != NULL);
2137
2138 uint8_t peer_mode = p_ccb->our_cfg.fcr.mode;
2139 bool can_renegotiate;
2140
2141 /* Skip if this is a reconfiguration from OPEN STATE or if FCR is not returned
2142 */
2143 if (!p_cfg->fcr_present || (p_ccb->config_done & RECONFIG_FLAG))
2144 return (false);
2145
2146 /* Only retry if there are more channel options to try */
2147 if (p_cfg->result == L2CAP_CFG_UNACCEPTABLE_PARAMS) {
2148 peer_mode = (p_cfg->fcr_present) ? p_cfg->fcr.mode : L2CAP_FCR_BASIC_MODE;
2149
2150 if (p_ccb->our_cfg.fcr.mode != peer_mode) {
2151 if ((--p_ccb->fcr_cfg_tries) == 0) {
2152 p_cfg->result = L2CAP_CFG_FAILED_NO_REASON;
2153 L2CAP_TRACE_WARNING("l2c_fcr_renegotiate_chan (Max retries exceeded)");
2154 }
2155
2156 can_renegotiate = false;
2157
2158 /* Try another supported mode if available based on our last attempted
2159 * channel */
2160 switch (p_ccb->our_cfg.fcr.mode) {
2161 /* Our Streaming mode request was unnacceptable; try ERTM or Basic */
2162 case L2CAP_FCR_STREAM_MODE:
2163 /* Peer wants ERTM and we support it */
2164 if ((peer_mode == L2CAP_FCR_ERTM_MODE) &&
2165 (p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
2166 L2CAP_TRACE_DEBUG("l2c_fcr_renegotiate_chan(Trying ERTM)");
2167 p_ccb->our_cfg.fcr.mode = L2CAP_FCR_ERTM_MODE;
2168 can_renegotiate = true;
2169 } else /* Falls through */
2170
2171 case L2CAP_FCR_ERTM_MODE: {
2172 /* We can try basic for any other peer mode if we support it */
2173 if (p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_BASIC) {
2174 L2CAP_TRACE_DEBUG("l2c_fcr_renegotiate_chan(Trying Basic)");
2175 can_renegotiate = true;
2176 p_ccb->our_cfg.fcr.mode = L2CAP_FCR_BASIC_MODE;
2177 }
2178 } break;
2179
2180 default:
2181 /* All other scenarios cannot be renegotiated */
2182 break;
2183 }
2184
2185 if (can_renegotiate) {
2186 p_ccb->our_cfg.fcr_present = true;
2187
2188 if (p_ccb->our_cfg.fcr.mode == L2CAP_FCR_BASIC_MODE) {
2189 p_ccb->our_cfg.fcs_present = false;
2190 p_ccb->our_cfg.ext_flow_spec_present = false;
2191
2192 /* Basic Mode uses ACL Data Pool, make sure the MTU fits */
2193 if ((p_cfg->mtu_present) && (p_cfg->mtu > L2CAP_MTU_SIZE)) {
2194 L2CAP_TRACE_WARNING("L2CAP - adjust MTU: %u too large", p_cfg->mtu);
2195 p_cfg->mtu = L2CAP_MTU_SIZE;
2196 }
2197 }
2198
2199 l2cu_process_our_cfg_req(p_ccb, &p_ccb->our_cfg);
2200 l2cu_send_peer_config_req(p_ccb, &p_ccb->our_cfg);
2201 alarm_set_on_queue(p_ccb->l2c_ccb_timer, L2CAP_CHNL_CFG_TIMEOUT_MS,
2202 l2c_ccb_timer_timeout, p_ccb,
2203 btu_general_alarm_queue);
2204 return (true);
2205 }
2206 }
2207 }
2208
2209 /* Disconnect if the channels do not match */
2210 if (p_ccb->our_cfg.fcr.mode != peer_mode) {
2211 L2CAP_TRACE_WARNING("L2C CFG: Channels incompatible (local %d, peer %d)",
2212 p_ccb->our_cfg.fcr.mode, peer_mode);
2213 l2cu_disconnect_chnl(p_ccb);
2214 }
2215
2216 return (false);
2217 }
2218
2219 /*******************************************************************************
2220 *
2221 * Function l2c_fcr_process_peer_cfg_req
2222 *
2223 * Description This function is called to process the FCR options passed
2224 * in the peer's configuration request.
2225 *
2226 * Returns uint8_t - L2CAP_PEER_CFG_OK, L2CAP_PEER_CFG_UNACCEPTABLE,
2227 * or L2CAP_PEER_CFG_DISCONNECT.
2228 *
2229 ******************************************************************************/
l2c_fcr_process_peer_cfg_req(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2230 uint8_t l2c_fcr_process_peer_cfg_req(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2231 CHECK(p_ccb != NULL);
2232 CHECK(p_cfg != NULL);
2233
2234 uint16_t max_retrans_size;
2235 uint8_t fcr_ok = L2CAP_PEER_CFG_OK;
2236
2237 p_ccb->p_lcb->w4_info_rsp =
2238 false; /* Handles T61x SonyEricsson Bug in Info Request */
2239
2240 L2CAP_TRACE_EVENT(
2241 "l2c_fcr_process_peer_cfg_req() CFG fcr_present:%d fcr.mode:%d CCB FCR "
2242 "mode:%d preferred: %u allowed:%u",
2243 p_cfg->fcr_present, p_cfg->fcr.mode, p_ccb->our_cfg.fcr.mode,
2244 p_ccb->ertm_info.preferred_mode, p_ccb->ertm_info.allowed_modes);
2245
2246 /* If Peer wants basic, we are done (accept it or disconnect) */
2247 if (p_cfg->fcr.mode == L2CAP_FCR_BASIC_MODE) {
2248 /* If we do not allow basic, disconnect */
2249 if (!(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_BASIC))
2250 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2251 }
2252
2253 /* Need to negotiate if our modes are not the same */
2254 else if (p_cfg->fcr.mode != p_ccb->ertm_info.preferred_mode) {
2255 /* If peer wants a mode that we don't support then retry our mode (ex.
2256 *rtx/flc), OR
2257 ** If we want ERTM and they wanted streaming retry our mode.
2258 ** Note: If we have already determined they support our mode previously
2259 ** from their EXF mask.
2260 */
2261 if ((((1 << p_cfg->fcr.mode) & L2CAP_FCR_CHAN_OPT_ALL_MASK) == 0) ||
2262 (p_ccb->ertm_info.preferred_mode == L2CAP_FCR_ERTM_MODE)) {
2263 p_cfg->fcr.mode = p_ccb->our_cfg.fcr.mode;
2264 p_cfg->fcr.tx_win_sz = p_ccb->our_cfg.fcr.tx_win_sz;
2265 p_cfg->fcr.max_transmit = p_ccb->our_cfg.fcr.max_transmit;
2266 fcr_ok = L2CAP_PEER_CFG_UNACCEPTABLE;
2267 }
2268
2269 /* If we wanted basic, then try to renegotiate it */
2270 else if (p_ccb->ertm_info.preferred_mode == L2CAP_FCR_BASIC_MODE) {
2271 p_cfg->fcr.mode = L2CAP_FCR_BASIC_MODE;
2272 p_cfg->fcr.max_transmit = p_cfg->fcr.tx_win_sz = 0;
2273 p_cfg->fcr.rtrans_tout = p_cfg->fcr.mon_tout = p_cfg->fcr.mps = 0;
2274 p_ccb->our_cfg.fcr.rtrans_tout = p_ccb->our_cfg.fcr.mon_tout =
2275 p_ccb->our_cfg.fcr.mps = 0;
2276 fcr_ok = L2CAP_PEER_CFG_UNACCEPTABLE;
2277 }
2278
2279 /* Only other valid case is if they want ERTM and we wanted STM which should
2280 be
2281 accepted if we support it; otherwise the channel should be disconnected
2282 */
2283 else if ((p_cfg->fcr.mode != L2CAP_FCR_ERTM_MODE) ||
2284 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
2285 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2286 }
2287 }
2288
2289 /* Configuration for FCR channels so make any adjustments and fwd to upper
2290 * layer */
2291 if (fcr_ok == L2CAP_PEER_CFG_OK) {
2292 /* by default don't need to send params in the response */
2293 p_ccb->out_cfg_fcr_present = false;
2294
2295 /* Make any needed adjustments for the response to the peer */
2296 if (p_cfg->fcr_present && p_cfg->fcr.mode != L2CAP_FCR_BASIC_MODE) {
2297 /* Peer desires to bypass FCS check, and streaming or ERTM mode */
2298 if (p_cfg->fcs_present) {
2299 p_ccb->peer_cfg.fcs = p_cfg->fcs;
2300 p_ccb->peer_cfg_bits |= L2CAP_CH_CFG_MASK_FCS;
2301 if (p_cfg->fcs == L2CAP_CFG_FCS_BYPASS)
2302 p_ccb->bypass_fcs |= L2CAP_CFG_FCS_PEER;
2303 }
2304
2305 max_retrans_size = p_ccb->ertm_info.fcr_tx_buf_size - sizeof(BT_HDR) -
2306 L2CAP_MIN_OFFSET - L2CAP_SDU_LEN_OFFSET -
2307 L2CAP_FCS_LEN;
2308
2309 /* Ensure the MPS is not bigger than the MTU */
2310 if ((p_cfg->fcr.mps == 0) || (p_cfg->fcr.mps > p_ccb->peer_cfg.mtu)) {
2311 p_cfg->fcr.mps = p_ccb->peer_cfg.mtu;
2312 p_ccb->out_cfg_fcr_present = true;
2313 }
2314
2315 /* Ensure the MPS is not bigger than our retransmission buffer */
2316 if (p_cfg->fcr.mps > max_retrans_size) {
2317 L2CAP_TRACE_DEBUG("CFG: Overriding MPS to %d (orig %d)",
2318 max_retrans_size, p_cfg->fcr.mps);
2319
2320 p_cfg->fcr.mps = max_retrans_size;
2321 p_ccb->out_cfg_fcr_present = true;
2322 }
2323
2324 if (p_cfg->fcr.mode == L2CAP_FCR_ERTM_MODE ||
2325 p_cfg->fcr.mode == L2CAP_FCR_STREAM_MODE) {
2326 /* Always respond with FCR ERTM parameters */
2327 p_ccb->out_cfg_fcr_present = true;
2328 }
2329 }
2330
2331 /* Everything ok, so save the peer's adjusted fcr options */
2332 p_ccb->peer_cfg.fcr = p_cfg->fcr;
2333
2334 if (p_cfg->fcr_present) p_ccb->peer_cfg_bits |= L2CAP_CH_CFG_MASK_FCR;
2335 } else if (fcr_ok == L2CAP_PEER_CFG_UNACCEPTABLE) {
2336 /* Allow peer only one retry for mode */
2337 if (p_ccb->peer_cfg_already_rejected)
2338 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2339 else
2340 p_ccb->peer_cfg_already_rejected = true;
2341 }
2342
2343 return (fcr_ok);
2344 }
2345
2346 #if (L2CAP_ERTM_STATS == TRUE)
2347 /*******************************************************************************
2348 *
2349 * Function l2c_fcr_collect_ack_delay
2350 *
2351 * Description collect throughput, delay, queue size of waiting ack
2352 *
2353 * Parameters
2354 * tL2C_CCB
2355 *
2356 * Returns void
2357 *
2358 ******************************************************************************/
l2c_fcr_collect_ack_delay(tL2C_CCB * p_ccb,uint8_t num_bufs_acked)2359 static void l2c_fcr_collect_ack_delay(tL2C_CCB* p_ccb, uint8_t num_bufs_acked) {
2360 uint32_t index;
2361 BT_HDR* p_buf;
2362 uint8_t* p;
2363 uint32_t timestamp, delay;
2364 uint8_t xx;
2365 uint8_t str[120];
2366
2367 index = p_ccb->fcrb.ack_delay_avg_index;
2368
2369 /* update sum, max and min of waiting for ack queue size */
2370 p_ccb->fcrb.ack_q_count_avg[index] +=
2371 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q);
2372
2373 if (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q) >
2374 p_ccb->fcrb.ack_q_count_max[index])
2375 p_ccb->fcrb.ack_q_count_max[index] =
2376 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q);
2377
2378 if (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q) <
2379 p_ccb->fcrb.ack_q_count_min[index])
2380 p_ccb->fcrb.ack_q_count_min[index] =
2381 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q);
2382
2383 /* update sum, max and min of round trip delay of acking */
2384 list_t* list = NULL;
2385 if (!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q))
2386 list = fixed_queue_get_list(p_ccb->fcrb.waiting_for_ack_q);
2387 if (list != NULL) {
2388 for (const list_node_t *node = list_begin(list), xx = 0;
2389 (node != list_end(list)) && (xx < num_bufs_acked);
2390 node = list_next(node), xx++) {
2391 p_buf = list_node(node);
2392 /* adding up length of acked I-frames to get throughput */
2393 p_ccb->fcrb.throughput[index] += p_buf->len - 8;
2394
2395 if (xx == num_bufs_acked - 1) {
2396 /* get timestamp from tx I-frame that receiver is acking */
2397 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len;
2398 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
2399 p += L2CAP_FCS_LEN;
2400 }
2401
2402 STREAM_TO_UINT32(timestamp, p);
2403 delay = time_get_os_boottime_ms() - timestamp;
2404
2405 p_ccb->fcrb.ack_delay_avg[index] += delay;
2406 if (delay > p_ccb->fcrb.ack_delay_max[index])
2407 p_ccb->fcrb.ack_delay_max[index] = delay;
2408 if (delay < p_ccb->fcrb.ack_delay_min[index])
2409 p_ccb->fcrb.ack_delay_min[index] = delay;
2410 }
2411 }
2412 }
2413
2414 p_ccb->fcrb.ack_delay_avg_count++;
2415
2416 /* calculate average and initialize next avg, min and max */
2417 if (p_ccb->fcrb.ack_delay_avg_count > L2CAP_ERTM_STATS_AVG_NUM_SAMPLES) {
2418 p_ccb->fcrb.ack_delay_avg_count = 0;
2419
2420 p_ccb->fcrb.ack_q_count_avg[index] /= L2CAP_ERTM_STATS_AVG_NUM_SAMPLES;
2421 p_ccb->fcrb.ack_delay_avg[index] /= L2CAP_ERTM_STATS_AVG_NUM_SAMPLES;
2422
2423 /* calculate throughput */
2424 timestamp = time_get_os_boottime_ms();
2425 if (timestamp - p_ccb->fcrb.throughput_start > 0)
2426 p_ccb->fcrb.throughput[index] /=
2427 (timestamp - p_ccb->fcrb.throughput_start);
2428
2429 p_ccb->fcrb.throughput_start = timestamp;
2430
2431 snprintf(
2432 str, sizeof(str),
2433 "[%02u] throughput: %5u, ack_delay avg:%3u, min:%3u, max:%3u, "
2434 "ack_q_count avg:%3u, min:%3u, max:%3u",
2435 index, p_ccb->fcrb.throughput[index], p_ccb->fcrb.ack_delay_avg[index],
2436 p_ccb->fcrb.ack_delay_min[index], p_ccb->fcrb.ack_delay_max[index],
2437 p_ccb->fcrb.ack_q_count_avg[index], p_ccb->fcrb.ack_q_count_min[index],
2438 p_ccb->fcrb.ack_q_count_max[index]);
2439
2440 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
2441 TRACE_TYPE_GENERIC, "%s", str);
2442
2443 index = (index + 1) % L2CAP_ERTM_STATS_NUM_AVG;
2444 p_ccb->fcrb.ack_delay_avg_index = index;
2445
2446 p_ccb->fcrb.ack_q_count_max[index] = 0;
2447 p_ccb->fcrb.ack_q_count_min[index] = 0xFFFFFFFF;
2448 p_ccb->fcrb.ack_q_count_avg[index] = 0;
2449
2450 p_ccb->fcrb.ack_delay_max[index] = 0;
2451 p_ccb->fcrb.ack_delay_min[index] = 0xFFFFFFFF;
2452 p_ccb->fcrb.ack_delay_avg[index] = 0;
2453
2454 p_ccb->fcrb.throughput[index] = 0;
2455 }
2456 }
2457 #endif
2458