1 /******************************************************************************
2 *
3 * Copyright 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 <log/log.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31
32 #include "bt_common.h"
33 #include "bt_types.h"
34 #include "btm_api.h"
35 #include "btm_int.h"
36 #include "btu.h"
37 #include "hcimsgs.h"
38 #include "l2c_api.h"
39 #include "l2c_int.h"
40 #include "l2cdefs.h"
41
42 /* Flag passed to retransmit_i_frames() when all packets should be retransmitted
43 */
44 #define L2C_FCR_RETX_ALL_PKTS 0xFF
45
46 /* this is the minimal offset required by OBX to process incoming packets */
47 static const uint16_t OBX_BUF_MIN_OFFSET = 4;
48
49 static const char* SAR_types[] = {"Unsegmented", "Start", "End",
50 "Continuation"};
51 static const char* SUP_types[] = {"RR", "REJ", "RNR", "SREJ"};
52
53 /* Look-up table for the CRC calculation */
54 static const unsigned short crctab[256] = {
55 0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241, 0xc601,
56 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440, 0xcc01, 0x0cc0,
57 0x0d80, 0xcd41, 0x0f00, 0xcfc1, 0xce81, 0x0e40, 0x0a00, 0xcac1, 0xcb81,
58 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841, 0xd801, 0x18c0, 0x1980, 0xd941,
59 0x1b00, 0xdbc1, 0xda81, 0x1a40, 0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01,
60 0x1dc0, 0x1c80, 0xdc41, 0x1400, 0xd4c1, 0xd581, 0x1540, 0xd701, 0x17c0,
61 0x1680, 0xd641, 0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081,
62 0x1040, 0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, 0xf281, 0x3240,
63 0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441, 0x3c00,
64 0xfcc1, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41, 0xfa01, 0x3ac0,
65 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840, 0x2800, 0xe8c1, 0xe981,
66 0x2940, 0xeb01, 0x2bc0, 0x2a80, 0xea41, 0xee01, 0x2ec0, 0x2f80, 0xef41,
67 0x2d00, 0xedc1, 0xec81, 0x2c40, 0xe401, 0x24c0, 0x2580, 0xe541, 0x2700,
68 0xe7c1, 0xe681, 0x2640, 0x2200, 0xe2c1, 0xe381, 0x2340, 0xe101, 0x21c0,
69 0x2080, 0xe041, 0xa001, 0x60c0, 0x6180, 0xa141, 0x6300, 0xa3c1, 0xa281,
70 0x6240, 0x6600, 0xa6c1, 0xa781, 0x6740, 0xa501, 0x65c0, 0x6480, 0xa441,
71 0x6c00, 0xacc1, 0xad81, 0x6d40, 0xaf01, 0x6fc0, 0x6e80, 0xae41, 0xaa01,
72 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840, 0x7800, 0xb8c1,
73 0xb981, 0x7940, 0xbb01, 0x7bc0, 0x7a80, 0xba41, 0xbe01, 0x7ec0, 0x7f80,
74 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40, 0xb401, 0x74c0, 0x7580, 0xb541,
75 0x7700, 0xb7c1, 0xb681, 0x7640, 0x7200, 0xb2c1, 0xb381, 0x7340, 0xb101,
76 0x71c0, 0x7080, 0xb041, 0x5000, 0x90c1, 0x9181, 0x5140, 0x9301, 0x53c0,
77 0x5280, 0x9241, 0x9601, 0x56c0, 0x5780, 0x9741, 0x5500, 0x95c1, 0x9481,
78 0x5440, 0x9c01, 0x5cc0, 0x5d80, 0x9d41, 0x5f00, 0x9fc1, 0x9e81, 0x5e40,
79 0x5a00, 0x9ac1, 0x9b81, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841, 0x8801,
80 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, 0x8a81, 0x4a40, 0x4e00, 0x8ec1,
81 0x8f81, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41, 0x4400, 0x84c1, 0x8581,
82 0x4540, 0x8701, 0x47c0, 0x4680, 0x8641, 0x8201, 0x42c0, 0x4380, 0x8341,
83 0x4100, 0x81c1, 0x8081, 0x4040,
84 };
85
86 /*******************************************************************************
87 * Static local functions
88 */
89 static bool process_reqseq(tL2C_CCB* p_ccb, uint16_t ctrl_word);
90 static void process_s_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word);
91 static void process_i_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word,
92 bool delay_ack);
93 static bool retransmit_i_frames(tL2C_CCB* p_ccb, uint8_t tx_seq);
94 static void prepare_I_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
95 bool is_retransmission);
96 static void process_stream_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf);
97 static bool do_sar_reassembly(tL2C_CCB* p_ccb, BT_HDR* p_buf,
98 uint16_t ctrl_word);
99
100 #if (L2CAP_ERTM_STATS == TRUE)
101 static void l2c_fcr_collect_ack_delay(tL2C_CCB* p_ccb, uint8_t num_bufs_acked);
102 #endif
103
104 /*******************************************************************************
105 *
106 * Function l2c_fcr_updcrc
107 *
108 * Description This function computes the CRC using the look-up table.
109 *
110 * Returns CRC
111 *
112 ******************************************************************************/
l2c_fcr_updcrc(unsigned short icrc,unsigned char * icp,int icnt)113 static unsigned short l2c_fcr_updcrc(unsigned short icrc, unsigned char* icp,
114 int icnt) {
115 unsigned short crc = icrc;
116 unsigned char* cp = icp;
117 int cnt = icnt;
118
119 while (cnt--) {
120 crc = ((crc >> 8) & 0xff) ^ crctab[(crc & 0xff) ^ *cp++];
121 }
122
123 return (crc);
124 }
125
126 /*******************************************************************************
127 *
128 * Function l2c_fcr_tx_get_fcs
129 *
130 * Description This function computes the CRC for a frame to be TXed.
131 *
132 * Returns CRC
133 *
134 ******************************************************************************/
l2c_fcr_tx_get_fcs(BT_HDR * p_buf)135 static uint16_t l2c_fcr_tx_get_fcs(BT_HDR* p_buf) {
136 uint8_t* p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
137
138 return (l2c_fcr_updcrc(L2CAP_FCR_INIT_CRC, p, p_buf->len));
139 }
140
141 /*******************************************************************************
142 *
143 * Function l2c_fcr_rx_get_fcs
144 *
145 * Description This function computes the CRC for a received frame.
146 *
147 * Returns CRC
148 *
149 ******************************************************************************/
l2c_fcr_rx_get_fcs(BT_HDR * p_buf)150 static uint16_t l2c_fcr_rx_get_fcs(BT_HDR* p_buf) {
151 uint8_t* p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
152
153 /* offset points past the L2CAP header, but the CRC check includes it */
154 p -= L2CAP_PKT_OVERHEAD;
155
156 return (
157 l2c_fcr_updcrc(L2CAP_FCR_INIT_CRC, p, p_buf->len + L2CAP_PKT_OVERHEAD));
158 }
159
160 /*******************************************************************************
161 *
162 * Function l2c_fcr_start_timer
163 *
164 * Description This function starts the (monitor or retransmission) timer.
165 *
166 * Returns -
167 *
168 ******************************************************************************/
l2c_fcr_start_timer(tL2C_CCB * p_ccb)169 void l2c_fcr_start_timer(tL2C_CCB* p_ccb) {
170 CHECK(p_ccb != NULL);
171 uint32_t tout;
172
173 /* The timers which are in milliseconds */
174 if (p_ccb->fcrb.wait_ack) {
175 tout = (uint32_t)p_ccb->our_cfg.fcr.mon_tout;
176 } else {
177 tout = (uint32_t)p_ccb->our_cfg.fcr.rtrans_tout;
178 }
179
180 /* Only start a timer that was not started */
181 if (!alarm_is_scheduled(p_ccb->fcrb.mon_retrans_timer)) {
182 alarm_set_on_mloop(p_ccb->fcrb.mon_retrans_timer, tout,
183 l2c_ccb_timer_timeout, p_ccb);
184 }
185 }
186
187 /*******************************************************************************
188 *
189 * Function l2c_fcr_stop_timer
190 *
191 * Description This function stops the (monitor or transmission) timer.
192 *
193 * Returns -
194 *
195 ******************************************************************************/
l2c_fcr_stop_timer(tL2C_CCB * p_ccb)196 void l2c_fcr_stop_timer(tL2C_CCB* p_ccb) {
197 CHECK(p_ccb != NULL);
198 alarm_cancel(p_ccb->fcrb.mon_retrans_timer);
199 }
200
201 /*******************************************************************************
202 *
203 * Function l2c_fcr_cleanup
204 *
205 * Description This function cleans up the variable used for
206 * flow-control/retrans.
207 *
208 * Returns -
209 *
210 ******************************************************************************/
l2c_fcr_cleanup(tL2C_CCB * p_ccb)211 void l2c_fcr_cleanup(tL2C_CCB* p_ccb) {
212 CHECK(p_ccb != NULL);
213 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
214
215 alarm_free(p_fcrb->mon_retrans_timer);
216 p_fcrb->mon_retrans_timer = NULL;
217 alarm_free(p_fcrb->ack_timer);
218 p_fcrb->ack_timer = NULL;
219
220 osi_free_and_reset((void**)&p_fcrb->p_rx_sdu);
221
222 fixed_queue_free(p_fcrb->waiting_for_ack_q, osi_free);
223 p_fcrb->waiting_for_ack_q = NULL;
224
225 fixed_queue_free(p_fcrb->srej_rcv_hold_q, osi_free);
226 p_fcrb->srej_rcv_hold_q = NULL;
227
228 fixed_queue_free(p_fcrb->retrans_q, osi_free);
229 p_fcrb->retrans_q = NULL;
230
231 #if (L2CAP_ERTM_STATS == TRUE)
232 if ((p_ccb->local_cid >= L2CAP_BASE_APPL_CID) &&
233 (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)) {
234 uint32_t dur = time_get_os_boottime_ms() - p_ccb->fcrb.connect_tick_count;
235 size_t p_str_size = 120;
236 char* p_str = (char*)osi_malloc(p_str_size);
237 uint16_t i;
238 uint32_t throughput_avg, ack_delay_avg, ack_q_count_avg;
239
240 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
241 TRACE_TYPE_GENERIC,
242 "--- L2CAP ERTM Stats for CID: 0x%04x Duration: %08ums",
243 p_ccb->local_cid, dur);
244 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
245 TRACE_TYPE_GENERIC,
246 "Retransmissions:%08u Times Flow Controlled:%08u Retrans "
247 "Touts:%08u Ack Touts:%08u",
248 p_ccb->fcrb.pkts_retransmitted, p_ccb->fcrb.xmit_window_closed,
249 p_ccb->fcrb.retrans_touts, p_ccb->fcrb.xmit_ack_touts);
250 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
251 TRACE_TYPE_GENERIC,
252 "Times there is less than 2 packets in controller when flow "
253 "controlled:%08u",
254 p_ccb->fcrb.controller_idle);
255 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
256 TRACE_TYPE_GENERIC,
257 "max_held_acks:%08u, in_cfg.fcr.tx_win_sz:%08u",
258 p_ccb->fcrb.max_held_acks, p_ccb->peer_cfg.fcr.tx_win_sz);
259
260 snprintf(
261 p_str, p_str_size,
262 "Sent Pkts:%08u Bytes:%10u(%06u/sec) RR:%08u REJ:%08u RNR:%08u "
263 "SREJ:%08u",
264 p_ccb->fcrb.ertm_pkt_counts[0], p_ccb->fcrb.ertm_byte_counts[0],
265 (dur >= 10 ? (p_ccb->fcrb.ertm_byte_counts[0] * 100) / (dur / 10) : 0),
266 p_ccb->fcrb.s_frames_sent[0], p_ccb->fcrb.s_frames_sent[1],
267 p_ccb->fcrb.s_frames_sent[2], p_ccb->fcrb.s_frames_sent[3]);
268
269 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
270 TRACE_TYPE_GENERIC, "%s", p_str);
271
272 snprintf(
273 p_str, p_str_size,
274 "Rcvd Pkts:%08u Bytes:%10u(%06u/sec) RR:%08u REJ:%08u RNR:%08u "
275 "SREJ:%08u",
276 p_ccb->fcrb.ertm_pkt_counts[1], p_ccb->fcrb.ertm_byte_counts[1],
277 (dur >= 10 ? (p_ccb->fcrb.ertm_byte_counts[1] * 100) / (dur / 10) : 0),
278 p_ccb->fcrb.s_frames_rcvd[0], p_ccb->fcrb.s_frames_rcvd[1],
279 p_ccb->fcrb.s_frames_rcvd[2], p_ccb->fcrb.s_frames_rcvd[3]);
280
281 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
282 TRACE_TYPE_GENERIC, "%s", p_str);
283
284 throughput_avg = 0;
285 ack_delay_avg = 0;
286 ack_q_count_avg = 0;
287
288 for (i = 0; i < L2CAP_ERTM_STATS_NUM_AVG; i++) {
289 if (i == p_ccb->fcrb.ack_delay_avg_index) {
290 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
291 TRACE_TYPE_GENERIC, "[%02u] collecting data ...", i);
292 continue;
293 }
294
295 snprintf(p_str, p_str_size,
296 "[%02u] throughput: %5u, ack_delay avg:%3u, min:%3u, max:%3u, "
297 "ack_q_count avg:%3u, min:%3u, max:%3u",
298 i, p_ccb->fcrb.throughput[i], p_ccb->fcrb.ack_delay_avg[i],
299 p_ccb->fcrb.ack_delay_min[i], p_ccb->fcrb.ack_delay_max[i],
300 p_ccb->fcrb.ack_q_count_avg[i], p_ccb->fcrb.ack_q_count_min[i],
301 p_ccb->fcrb.ack_q_count_max[i]);
302
303 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
304 TRACE_TYPE_GENERIC, "%s", p_str);
305
306 throughput_avg += p_ccb->fcrb.throughput[i];
307 ack_delay_avg += p_ccb->fcrb.ack_delay_avg[i];
308 ack_q_count_avg += p_ccb->fcrb.ack_q_count_avg[i];
309 }
310
311 throughput_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
312 ack_delay_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
313 ack_q_count_avg /= (L2CAP_ERTM_STATS_NUM_AVG - 1);
314
315 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
316 TRACE_TYPE_GENERIC,
317 "throughput_avg: %8u (kbytes/sec), ack_delay_avg: %8u ms, "
318 "ack_q_count_avg: %8u",
319 throughput_avg, ack_delay_avg, ack_q_count_avg);
320
321 osi_free(p_str);
322
323 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
324 TRACE_TYPE_GENERIC, "---");
325 }
326 #endif
327
328 memset(p_fcrb, 0, sizeof(tL2C_FCRB));
329 }
330
331 /*******************************************************************************
332 *
333 * Function l2c_fcr_clone_buf
334 *
335 * Description This function allocates and copies requested part of a
336 * buffer at a new-offset.
337 *
338 * Returns pointer to new buffer
339 *
340 ******************************************************************************/
l2c_fcr_clone_buf(BT_HDR * p_buf,uint16_t new_offset,uint16_t no_of_bytes)341 BT_HDR* l2c_fcr_clone_buf(BT_HDR* p_buf, uint16_t new_offset,
342 uint16_t no_of_bytes) {
343 CHECK(p_buf != NULL);
344 /*
345 * NOTE: We allocate extra L2CAP_FCS_LEN octets, in case we need to put
346 * the FCS (Frame Check Sequence) at the end of the buffer.
347 */
348 uint16_t buf_size = no_of_bytes + sizeof(BT_HDR) + new_offset + L2CAP_FCS_LEN;
349 #if (L2CAP_ERTM_STATS == TRUE)
350 /*
351 * NOTE: If L2CAP_ERTM_STATS is enabled, we need 4 extra octets at the
352 * end for a timestamp at the end of an I-frame.
353 */
354 buf_size += sizeof(uint32_t);
355 #endif
356 BT_HDR* p_buf2 = (BT_HDR*)osi_malloc(buf_size);
357
358 p_buf2->offset = new_offset;
359 p_buf2->len = no_of_bytes;
360 memcpy(((uint8_t*)(p_buf2 + 1)) + p_buf2->offset,
361 ((uint8_t*)(p_buf + 1)) + p_buf->offset, no_of_bytes);
362
363 return (p_buf2);
364 }
365
366 /*******************************************************************************
367 *
368 * Function l2c_fcr_is_flow_controlled
369 *
370 * Description This function checks if the CCB is flow controlled by peer.
371 *
372 * Returns The control word
373 *
374 ******************************************************************************/
l2c_fcr_is_flow_controlled(tL2C_CCB * p_ccb)375 bool l2c_fcr_is_flow_controlled(tL2C_CCB* p_ccb) {
376 CHECK(p_ccb != NULL);
377 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
378 /* Check if remote side flowed us off or the transmit window is full */
379 if ((p_ccb->fcrb.remote_busy) ||
380 (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q) >=
381 p_ccb->peer_cfg.fcr.tx_win_sz)) {
382 #if (L2CAP_ERTM_STATS == TRUE)
383 if (!fixed_queue_is_empty(p_ccb->xmit_hold_q)) {
384 p_ccb->fcrb.xmit_window_closed++;
385
386 if ((p_ccb->p_lcb->sent_not_acked < 2) &&
387 (l2cb.controller_xmit_window > 0))
388 p_ccb->fcrb.controller_idle++;
389 }
390 #endif
391 return (true);
392 }
393 }
394 return (false);
395 }
396
397 /*******************************************************************************
398 *
399 * Function prepare_I_frame
400 *
401 * Description This function sets the FCR variables in an I-frame that is
402 * about to be sent to HCI for transmission. This may be the
403 * first time the I-frame is sent, or a retransmission
404 *
405 * Returns -
406 *
407 ******************************************************************************/
prepare_I_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,bool is_retransmission)408 static void prepare_I_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
409 bool is_retransmission) {
410 CHECK(p_ccb != NULL);
411 CHECK(p_buf != NULL);
412 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
413 uint8_t* p;
414 uint16_t fcs;
415 uint16_t ctrl_word;
416 bool set_f_bit = p_fcrb->send_f_rsp;
417
418 p_fcrb->send_f_rsp = false;
419
420 if (is_retransmission) {
421 /* Get the old control word and clear out the old req_seq and F bits */
422 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
423
424 STREAM_TO_UINT16(ctrl_word, p);
425
426 ctrl_word &= ~(L2CAP_FCR_REQ_SEQ_BITS + L2CAP_FCR_F_BIT);
427 } else {
428 ctrl_word = p_buf->layer_specific & L2CAP_FCR_SEG_BITS; /* SAR bits */
429 ctrl_word |=
430 (p_fcrb->next_tx_seq << L2CAP_FCR_TX_SEQ_BITS_SHIFT); /* Tx Seq */
431
432 p_fcrb->next_tx_seq = (p_fcrb->next_tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
433 }
434
435 /* Set the F-bit and reqseq only if using re-transmission mode */
436 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
437 if (set_f_bit) ctrl_word |= L2CAP_FCR_F_BIT;
438
439 ctrl_word |= (p_fcrb->next_seq_expected) << L2CAP_FCR_REQ_SEQ_BITS_SHIFT;
440
441 p_fcrb->last_ack_sent = p_ccb->fcrb.next_seq_expected;
442
443 alarm_cancel(p_ccb->fcrb.ack_timer);
444 }
445
446 /* Set the control word */
447 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
448
449 UINT16_TO_STREAM(p, ctrl_word);
450
451 /* Compute the FCS and add to the end of the buffer if not bypassed */
452 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
453 /* length field in l2cap header has to include FCS length */
454 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
455 UINT16_TO_STREAM(p, p_buf->len + L2CAP_FCS_LEN - L2CAP_PKT_OVERHEAD);
456
457 /* Calculate the FCS */
458 fcs = l2c_fcr_tx_get_fcs(p_buf);
459
460 /* Point to the end of the buffer and put the FCS there */
461 /*
462 * NOTE: Here we assume the allocated buffer is large enough
463 * to include extra L2CAP_FCS_LEN octets at the end.
464 */
465 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len;
466
467 UINT16_TO_STREAM(p, fcs);
468
469 p_buf->len += L2CAP_FCS_LEN;
470 }
471
472 if (is_retransmission) {
473 L2CAP_TRACE_EVENT(
474 "L2CAP eRTM ReTx I-frame CID: 0x%04x Len: %u SAR: %s TxSeq: %u "
475 "ReqSeq: %u F: %u",
476 p_ccb->local_cid, p_buf->len,
477 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
478 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
479 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
480 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
481 } else {
482 L2CAP_TRACE_EVENT(
483 "L2CAP eRTM Tx I-frame CID: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
484 "ReqSeq: %u F: %u",
485 p_ccb->local_cid, p_buf->len,
486 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
487 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
488 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
489 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
490 }
491
492 /* Start the retransmission timer if not already running */
493 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)
494 l2c_fcr_start_timer(p_ccb);
495 }
496
497 /*******************************************************************************
498 *
499 * Function l2c_fcr_send_S_frame
500 *
501 * Description This function formats and sends an S-frame for transmission.
502 *
503 * Returns -
504 *
505 ******************************************************************************/
l2c_fcr_send_S_frame(tL2C_CCB * p_ccb,uint16_t function_code,uint16_t pf_bit)506 void l2c_fcr_send_S_frame(tL2C_CCB* p_ccb, uint16_t function_code,
507 uint16_t pf_bit) {
508 CHECK(p_ccb != NULL);
509 uint8_t* p;
510 uint16_t ctrl_word;
511 uint16_t fcs;
512
513 if ((!p_ccb->in_use) || (p_ccb->chnl_state != CST_OPEN)) return;
514
515 #if (L2CAP_ERTM_STATS == TRUE)
516 p_ccb->fcrb.s_frames_sent[function_code]++;
517 #endif
518
519 if (pf_bit == L2CAP_FCR_P_BIT) {
520 p_ccb->fcrb.wait_ack = true;
521
522 l2c_fcr_stop_timer(p_ccb); /* Restart the monitor timer */
523 l2c_fcr_start_timer(p_ccb);
524 }
525
526 /* Create the control word to use */
527 ctrl_word = (function_code << L2CAP_FCR_SUP_SHIFT) | L2CAP_FCR_S_FRAME_BIT;
528 ctrl_word |= (p_ccb->fcrb.next_seq_expected << L2CAP_FCR_REQ_SEQ_BITS_SHIFT);
529 ctrl_word |= pf_bit;
530
531 BT_HDR* p_buf = (BT_HDR*)osi_malloc(L2CAP_CMD_BUF_SIZE);
532 p_buf->offset = HCI_DATA_PREAMBLE_SIZE;
533 p_buf->len = L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD;
534
535 /* Set the pointer to the beginning of the data */
536 p = (uint8_t*)(p_buf + 1) + p_buf->offset;
537
538 /* Put in the L2CAP header */
539 UINT16_TO_STREAM(p, L2CAP_FCR_OVERHEAD + L2CAP_FCS_LEN);
540 UINT16_TO_STREAM(p, p_ccb->remote_cid);
541 UINT16_TO_STREAM(p, ctrl_word);
542
543 /* Compute the FCS and add to the end of the buffer if not bypassed */
544 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
545 fcs = l2c_fcr_tx_get_fcs(p_buf);
546
547 UINT16_TO_STREAM(p, fcs);
548 p_buf->len += L2CAP_FCS_LEN;
549 } else {
550 /* rewrite the length without FCS length */
551 p -= 6;
552 UINT16_TO_STREAM(p, L2CAP_FCR_OVERHEAD);
553 }
554
555 /* Now, the HCI transport header */
556 p_buf->layer_specific = L2CAP_NON_FLUSHABLE_PKT;
557 l2cu_set_acl_hci_header(p_buf, p_ccb);
558
559 if ((((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 1) ||
560 (((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 3)) {
561 L2CAP_TRACE_WARNING(
562 "L2CAP eRTM Tx S-frame CID: 0x%04x ctrlword: 0x%04x Type: %s "
563 "ReqSeq: %u P: %u F: %u",
564 p_ccb->local_cid, ctrl_word,
565 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
566 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
567 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
568 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
569 L2CAP_TRACE_WARNING(" Buf Len: %u", p_buf->len);
570 } else {
571 L2CAP_TRACE_EVENT(
572 "L2CAP eRTM Tx S-frame CID: 0x%04x ctrlword: 0x%04x Type: %s "
573 "ReqSeq: %u P: %u F: %u",
574 p_ccb->local_cid, ctrl_word,
575 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
576 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
577 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
578 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
579 L2CAP_TRACE_EVENT(" Buf Len: %u", p_buf->len);
580 }
581
582 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, p_buf);
583
584 p_ccb->fcrb.last_ack_sent = p_ccb->fcrb.next_seq_expected;
585
586 alarm_cancel(p_ccb->fcrb.ack_timer);
587 }
588
589 /*******************************************************************************
590 *
591 * Function l2c_fcr_proc_pdu
592 *
593 * Description This function is the entry point for processing of a
594 * received PDU when in flow control and/or retransmission
595 * modes.
596 *
597 * Returns -
598 *
599 ******************************************************************************/
l2c_fcr_proc_pdu(tL2C_CCB * p_ccb,BT_HDR * p_buf)600 void l2c_fcr_proc_pdu(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
601 CHECK(p_ccb != NULL);
602 CHECK(p_buf != NULL);
603 uint8_t* p;
604 uint16_t fcs;
605 uint16_t min_pdu_len;
606 uint16_t ctrl_word;
607
608 /* Check the length */
609 min_pdu_len = (p_ccb->bypass_fcs == L2CAP_BYPASS_FCS)
610 ? (uint16_t)L2CAP_FCR_OVERHEAD
611 : (uint16_t)(L2CAP_FCS_LEN + L2CAP_FCR_OVERHEAD);
612
613 if (p_buf->len < min_pdu_len) {
614 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x Len too short: %u",
615 p_ccb->local_cid, p_buf->len);
616 osi_free(p_buf);
617 return;
618 }
619
620 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_STREAM_MODE) {
621 process_stream_frame(p_ccb, p_buf);
622 return;
623 }
624
625 /* Get the control word */
626 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
627 STREAM_TO_UINT16(ctrl_word, p);
628
629 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) {
630 if ((((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 1) ||
631 (((ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT) == 3)) {
632 /* REJ or SREJ */
633 L2CAP_TRACE_WARNING(
634 "L2CAP eRTM Rx S-frame: cid: 0x%04x Len: %u Type: %s ReqSeq: %u "
635 "P: %u F: %u",
636 p_ccb->local_cid, p_buf->len,
637 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
638 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
639 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
640 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
641 } else {
642 L2CAP_TRACE_EVENT(
643 "L2CAP eRTM Rx S-frame: cid: 0x%04x Len: %u Type: %s ReqSeq: %u "
644 "P: %u F: %u",
645 p_ccb->local_cid, p_buf->len,
646 SUP_types[(ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT],
647 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
648 (ctrl_word & L2CAP_FCR_P_BIT) >> L2CAP_FCR_P_BIT_SHIFT,
649 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
650 }
651 } else {
652 L2CAP_TRACE_EVENT(
653 "L2CAP eRTM Rx I-frame: cid: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
654 "ReqSeq: %u F: %u",
655 p_ccb->local_cid, p_buf->len,
656 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
657 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
658 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
659 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
660 }
661
662 L2CAP_TRACE_EVENT(
663 " eRTM Rx Nxt_tx_seq %u, Lst_rx_ack %u, Nxt_seq_exp %u, Lst_ack_snt "
664 "%u, wt_q.cnt %u, tries %u",
665 p_ccb->fcrb.next_tx_seq, p_ccb->fcrb.last_rx_ack,
666 p_ccb->fcrb.next_seq_expected, p_ccb->fcrb.last_ack_sent,
667 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q), p_ccb->fcrb.num_tries);
668
669 /* Verify FCS if using */
670 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
671 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len - L2CAP_FCS_LEN;
672
673 /* Extract and drop the FCS from the packet */
674 STREAM_TO_UINT16(fcs, p);
675 p_buf->len -= L2CAP_FCS_LEN;
676
677 if (l2c_fcr_rx_get_fcs(p_buf) != fcs) {
678 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x BAD FCS",
679 p_ccb->local_cid);
680 osi_free(p_buf);
681 return;
682 }
683 }
684
685 /* Get the control word */
686 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
687
688 STREAM_TO_UINT16(ctrl_word, p);
689
690 p_buf->len -= L2CAP_FCR_OVERHEAD;
691 p_buf->offset += L2CAP_FCR_OVERHEAD;
692
693 /* If we had a poll bit outstanding, check if we got a final response */
694 if (p_ccb->fcrb.wait_ack) {
695 /* If final bit not set, ignore the frame unless it is a polled S-frame */
696 if (!(ctrl_word & L2CAP_FCR_F_BIT)) {
697 if ((ctrl_word & L2CAP_FCR_P_BIT) &&
698 (ctrl_word & L2CAP_FCR_S_FRAME_BIT)) {
699 if (p_ccb->fcrb.srej_sent)
700 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, L2CAP_FCR_F_BIT);
701 else if (p_ccb->fcrb.local_busy)
702 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_F_BIT);
703 else
704 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_F_BIT);
705
706 /* Got a poll while in wait_ack state, so re-start our timer with
707 * 1-second */
708 /* This is a small optimization... the monitor timer is 12 secs, but we
709 * saw */
710 /* that if the other side sends us a poll when we are waiting for a
711 * final, */
712 /* then it speeds up recovery significantly if we poll him back soon
713 * after his poll. */
714 alarm_set_on_mloop(p_ccb->fcrb.mon_retrans_timer, BT_1SEC_TIMEOUT_MS,
715 l2c_ccb_timer_timeout, p_ccb);
716 }
717 osi_free(p_buf);
718 return;
719 }
720
721 p_ccb->fcrb.wait_ack = false;
722
723 /* P and F are mutually exclusive */
724 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) ctrl_word &= ~L2CAP_FCR_P_BIT;
725
726 if (fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q))
727 p_ccb->fcrb.num_tries = 0;
728
729 l2c_fcr_stop_timer(p_ccb);
730 } else {
731 /* Otherwise, ensure the final bit is ignored */
732 ctrl_word &= ~L2CAP_FCR_F_BIT;
733 }
734
735 /* Process receive sequence number */
736 if (!process_reqseq(p_ccb, ctrl_word)) {
737 osi_free(p_buf);
738 return;
739 }
740
741 /* Process based on whether it is an S-frame or an I-frame */
742 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT)
743 process_s_frame(p_ccb, p_buf, ctrl_word);
744 else
745 process_i_frame(p_ccb, p_buf, ctrl_word, false);
746
747 /* Return if the channel got disconnected by a bad packet or max
748 * retransmissions */
749 if ((!p_ccb->in_use) || (p_ccb->chnl_state != CST_OPEN)) return;
750
751 /* If we have some buffers held while doing SREJ, and SREJ has cleared,
752 * process them now */
753 if ((!p_ccb->fcrb.local_busy) && (!p_ccb->fcrb.srej_sent) &&
754 (!fixed_queue_is_empty(p_ccb->fcrb.srej_rcv_hold_q))) {
755 fixed_queue_t* temp_q = p_ccb->fcrb.srej_rcv_hold_q;
756 p_ccb->fcrb.srej_rcv_hold_q = fixed_queue_new(SIZE_MAX);
757
758 while ((p_buf = (BT_HDR*)fixed_queue_try_dequeue(temp_q)) != NULL) {
759 if (p_ccb->in_use && (p_ccb->chnl_state == CST_OPEN)) {
760 /* Get the control word */
761 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset - L2CAP_FCR_OVERHEAD;
762
763 STREAM_TO_UINT16(ctrl_word, p);
764
765 L2CAP_TRACE_DEBUG(
766 "l2c_fcr_proc_pdu() CID: 0x%04x Process Buffer from SREJ_Hold_Q "
767 "TxSeq: %u Expected_Seq: %u",
768 p_ccb->local_cid,
769 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
770 p_ccb->fcrb.next_seq_expected);
771
772 /* Process the SREJ held I-frame, but do not send an RR for each
773 * individual frame */
774 process_i_frame(p_ccb, p_buf, ctrl_word, true);
775 } else
776 osi_free(p_buf);
777
778 /* If more frames were lost during SREJ, send a REJ */
779 if (p_ccb->fcrb.rej_after_srej) {
780 p_ccb->fcrb.rej_after_srej = false;
781 p_ccb->fcrb.rej_sent = true;
782
783 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_REJ, 0);
784 }
785 }
786 fixed_queue_free(temp_q, NULL);
787
788 /* Now, if needed, send one RR for the whole held queue */
789 if ((!p_ccb->fcrb.local_busy) && (!p_ccb->fcrb.rej_sent) &&
790 (!p_ccb->fcrb.srej_sent) &&
791 (p_ccb->fcrb.next_seq_expected != p_ccb->fcrb.last_ack_sent))
792 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
793 else {
794 L2CAP_TRACE_DEBUG(
795 "l2c_fcr_proc_pdu() not sending RR CID: 0x%04x local_busy:%d "
796 "rej_sent:%d srej_sent:%d Expected_Seq:%u Last_Ack:%u",
797 p_ccb->local_cid, p_ccb->fcrb.local_busy, p_ccb->fcrb.rej_sent,
798 p_ccb->fcrb.srej_sent, p_ccb->fcrb.next_seq_expected,
799 p_ccb->fcrb.last_ack_sent);
800 }
801 }
802
803 /* If a window has opened, check if we can send any more packets */
804 if ((!fixed_queue_is_empty(p_ccb->fcrb.retrans_q) ||
805 !fixed_queue_is_empty(p_ccb->xmit_hold_q)) &&
806 (!p_ccb->fcrb.wait_ack) && (!l2c_fcr_is_flow_controlled(p_ccb))) {
807 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, NULL);
808 }
809 }
810
811 /*******************************************************************************
812 *
813 * Function l2c_lcc_proc_pdu
814 *
815 * Description This function is the entry point for processing of a
816 * received PDU when in LE Coc flow control modes.
817 *
818 * Returns -
819 *
820 ******************************************************************************/
l2c_lcc_proc_pdu(tL2C_CCB * p_ccb,BT_HDR * p_buf)821 void l2c_lcc_proc_pdu(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
822 CHECK(p_ccb != NULL);
823 CHECK(p_buf != NULL);
824 uint8_t* p = (uint8_t*)(p_buf + 1) + p_buf->offset;
825 uint16_t sdu_length;
826 BT_HDR* p_data = NULL;
827
828 /* Buffer length should not exceed local mps */
829 if (p_buf->len > p_ccb->local_conn_cfg.mps) {
830 /* Discard the buffer */
831 osi_free(p_buf);
832 return;
833 }
834
835 if (p_ccb->is_first_seg) {
836 if (p_buf->len < sizeof(sdu_length)) {
837 L2CAP_TRACE_ERROR("%s: buffer length=%d too small. Need at least 2.",
838 __func__, p_buf->len);
839 android_errorWriteWithInfoLog(0x534e4554, "120665616", -1, NULL, 0);
840 /* Discard the buffer */
841 osi_free(p_buf);
842 return;
843 }
844 STREAM_TO_UINT16(sdu_length, p);
845
846 /* Check the SDU Length with local MTU size */
847 if (sdu_length > p_ccb->local_conn_cfg.mtu) {
848 /* Discard the buffer */
849 osi_free(p_buf);
850 return;
851 }
852
853 p_buf->len -= sizeof(sdu_length);
854 p_buf->offset += sizeof(sdu_length);
855
856 if (sdu_length < p_buf->len) {
857 L2CAP_TRACE_ERROR("%s: Invalid sdu_length: %d", __func__, sdu_length);
858 android_errorWriteWithInfoLog(0x534e4554, "112321180", -1, NULL, 0);
859 /* Discard the buffer */
860 osi_free(p_buf);
861 return;
862 }
863
864 p_data = (BT_HDR*)osi_malloc(BT_HDR_SIZE + sdu_length);
865 if (p_data == NULL) {
866 osi_free(p_buf);
867 return;
868 }
869
870 p_ccb->ble_sdu = p_data;
871 p_data->len = 0;
872 p_ccb->ble_sdu_length = sdu_length;
873 L2CAP_TRACE_DEBUG("%s SDU Length = %d", __func__, sdu_length);
874 p_data->offset = 0;
875
876 } else {
877 p_data = p_ccb->ble_sdu;
878 if (p_buf->len > (p_ccb->ble_sdu_length - p_data->len)) {
879 L2CAP_TRACE_ERROR("%s: buffer length=%d too big. max=%d. Dropped",
880 __func__, p_data->len,
881 (p_ccb->ble_sdu_length - p_data->len));
882 android_errorWriteWithInfoLog(0x534e4554, "75298652", -1, NULL, 0);
883 osi_free(p_buf);
884
885 /* Throw away all pending fragments and disconnects */
886 p_ccb->is_first_seg = true;
887 osi_free(p_ccb->ble_sdu);
888 p_ccb->ble_sdu = NULL;
889 p_ccb->ble_sdu_length = 0;
890 l2cu_disconnect_chnl(p_ccb);
891 return;
892 }
893 }
894
895 memcpy((uint8_t*)(p_data + 1) + p_data->offset + p_data->len,
896 (uint8_t*)(p_buf + 1) + p_buf->offset, p_buf->len);
897 p_data->len += p_buf->len;
898 p = (uint8_t*)(p_data + 1) + p_data->offset;
899 if (p_data->len == p_ccb->ble_sdu_length) {
900 l2c_csm_execute(p_ccb, L2CEVT_L2CAP_DATA, p_data);
901 p_ccb->is_first_seg = true;
902 p_ccb->ble_sdu = NULL;
903 p_ccb->ble_sdu_length = 0;
904 } else if (p_data->len < p_ccb->ble_sdu_length) {
905 p_ccb->is_first_seg = false;
906 }
907
908 osi_free(p_buf);
909 return;
910 }
911
912 /*******************************************************************************
913 *
914 * Function l2c_fcr_proc_tout
915 *
916 * Description Handle a timeout. We should be in error recovery state.
917 *
918 * Returns -
919 *
920 ******************************************************************************/
l2c_fcr_proc_tout(tL2C_CCB * p_ccb)921 void l2c_fcr_proc_tout(tL2C_CCB* p_ccb) {
922 CHECK(p_ccb != NULL);
923 L2CAP_TRACE_DEBUG(
924 "l2c_fcr_proc_tout: CID: 0x%04x num_tries: %u (max: %u) wait_ack: %u "
925 "ack_q_count: %u",
926 p_ccb->local_cid, p_ccb->fcrb.num_tries, p_ccb->peer_cfg.fcr.max_transmit,
927 p_ccb->fcrb.wait_ack, fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
928
929 #if (L2CAP_ERTM_STATS == TRUE)
930 p_ccb->fcrb.retrans_touts++;
931 #endif
932
933 if ((p_ccb->peer_cfg.fcr.max_transmit != 0) &&
934 (++p_ccb->fcrb.num_tries > p_ccb->peer_cfg.fcr.max_transmit)) {
935 l2cu_disconnect_chnl(p_ccb);
936 } else {
937 if (!p_ccb->fcrb.srej_sent && !p_ccb->fcrb.rej_sent) {
938 if (p_ccb->fcrb.local_busy)
939 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_P_BIT);
940 else
941 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_P_BIT);
942 }
943 }
944 }
945
946 /*******************************************************************************
947 *
948 * Function l2c_fcr_proc_ack_tout
949 *
950 * Description Send RR/RNR if we have not acked I frame
951 *
952 * Returns -
953 *
954 ******************************************************************************/
l2c_fcr_proc_ack_tout(tL2C_CCB * p_ccb)955 void l2c_fcr_proc_ack_tout(tL2C_CCB* p_ccb) {
956 CHECK(p_ccb != NULL);
957 L2CAP_TRACE_DEBUG(
958 "l2c_fcr_proc_ack_tout: CID: 0x%04x State: %u Wack:%u Rq:%d Acked:%d",
959 p_ccb->local_cid, p_ccb->chnl_state, p_ccb->fcrb.wait_ack,
960 p_ccb->fcrb.next_seq_expected, p_ccb->fcrb.last_ack_sent);
961
962 if ((p_ccb->chnl_state == CST_OPEN) && (!p_ccb->fcrb.wait_ack) &&
963 (p_ccb->fcrb.last_ack_sent != p_ccb->fcrb.next_seq_expected)) {
964 #if (L2CAP_ERTM_STATS == TRUE)
965 p_ccb->fcrb.xmit_ack_touts++;
966 #endif
967 if (p_ccb->fcrb.local_busy)
968 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
969 else
970 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
971 }
972 }
973
974 /*******************************************************************************
975 *
976 * Function process_reqseq
977 *
978 * Description Handle receive sequence number
979 *
980 * Returns -
981 *
982 ******************************************************************************/
process_reqseq(tL2C_CCB * p_ccb,uint16_t ctrl_word)983 static bool process_reqseq(tL2C_CCB* p_ccb, uint16_t ctrl_word) {
984 CHECK(p_ccb != NULL);
985 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
986 uint8_t req_seq, num_bufs_acked, xx;
987 uint16_t ls;
988 uint16_t full_sdus_xmitted;
989
990 /* Receive sequence number does not ack anything for SREJ with P-bit set to
991 * zero */
992 if ((ctrl_word & L2CAP_FCR_S_FRAME_BIT) &&
993 ((ctrl_word & L2CAP_FCR_SUP_BITS) ==
994 (L2CAP_FCR_SUP_SREJ << L2CAP_FCR_SUP_SHIFT)) &&
995 ((ctrl_word & L2CAP_FCR_P_BIT) == 0)) {
996 /* If anything still waiting for ack, restart the timer if it was stopped */
997 if (!fixed_queue_is_empty(p_fcrb->waiting_for_ack_q))
998 l2c_fcr_start_timer(p_ccb);
999
1000 return (true);
1001 }
1002
1003 /* Extract the receive sequence number from the control word */
1004 req_seq =
1005 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT;
1006
1007 num_bufs_acked = (req_seq - p_fcrb->last_rx_ack) & L2CAP_FCR_SEQ_MODULO;
1008
1009 /* Verify the request sequence is in range before proceeding */
1010 if (num_bufs_acked > fixed_queue_length(p_fcrb->waiting_for_ack_q)) {
1011 /* The channel is closed if ReqSeq is not in range */
1012 L2CAP_TRACE_WARNING(
1013 "L2CAP eRTM Frame BAD Req_Seq - ctrl_word: 0x%04x req_seq 0x%02x "
1014 "last_rx_ack: 0x%02x QCount: %u",
1015 ctrl_word, req_seq, p_fcrb->last_rx_ack,
1016 fixed_queue_length(p_fcrb->waiting_for_ack_q));
1017
1018 l2cu_disconnect_chnl(p_ccb);
1019 return (false);
1020 }
1021
1022 p_fcrb->last_rx_ack = req_seq;
1023
1024 /* Now we can release all acknowledged frames, and restart the retransmission
1025 * timer if needed */
1026 if (num_bufs_acked != 0) {
1027 p_fcrb->num_tries = 0;
1028 full_sdus_xmitted = 0;
1029
1030 #if (L2CAP_ERTM_STATS == TRUE)
1031 l2c_fcr_collect_ack_delay(p_ccb, num_bufs_acked);
1032 #endif
1033
1034 for (xx = 0; xx < num_bufs_acked; xx++) {
1035 BT_HDR* p_tmp =
1036 (BT_HDR*)fixed_queue_try_dequeue(p_fcrb->waiting_for_ack_q);
1037 ls = p_tmp->layer_specific & L2CAP_FCR_SAR_BITS;
1038
1039 if ((ls == L2CAP_FCR_UNSEG_SDU) || (ls == L2CAP_FCR_END_SDU))
1040 full_sdus_xmitted++;
1041
1042 osi_free(p_tmp);
1043 }
1044
1045 /* If we are still in a wait_ack state, do not mess with the timer */
1046 if (!p_ccb->fcrb.wait_ack) l2c_fcr_stop_timer(p_ccb);
1047
1048 /* Check if we need to call the "packet_sent" callback */
1049 if ((p_ccb->p_rcb) && (p_ccb->p_rcb->api.pL2CA_TxComplete_Cb) &&
1050 (full_sdus_xmitted)) {
1051 /* Special case for eRTM, if all packets sent, send 0xFFFF */
1052 if (fixed_queue_is_empty(p_fcrb->waiting_for_ack_q) &&
1053 fixed_queue_is_empty(p_ccb->xmit_hold_q)) {
1054 full_sdus_xmitted = 0xFFFF;
1055 }
1056
1057 (*p_ccb->p_rcb->api.pL2CA_TxComplete_Cb)(p_ccb->local_cid,
1058 full_sdus_xmitted);
1059 }
1060 }
1061
1062 /* If anything still waiting for ack, restart the timer if it was stopped */
1063 if (!fixed_queue_is_empty(p_fcrb->waiting_for_ack_q))
1064 l2c_fcr_start_timer(p_ccb);
1065 return (true);
1066 }
1067
1068 /*******************************************************************************
1069 *
1070 * Function process_s_frame
1071 *
1072 * Description Process an S frame
1073 *
1074 * Returns -
1075 *
1076 ******************************************************************************/
process_s_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word)1077 static void process_s_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf,
1078 uint16_t ctrl_word) {
1079 CHECK(p_ccb != NULL);
1080 CHECK(p_buf != NULL);
1081
1082 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1083 uint16_t s_frame_type =
1084 (ctrl_word & L2CAP_FCR_SUP_BITS) >> L2CAP_FCR_SUP_SHIFT;
1085 bool remote_was_busy;
1086 bool all_ok = true;
1087
1088 if (p_buf->len != 0) {
1089 L2CAP_TRACE_WARNING("Incorrect S-frame Length (%d)", p_buf->len);
1090 }
1091
1092 L2CAP_TRACE_DEBUG("process_s_frame ctrl_word 0x%04x fcrb_remote_busy:%d",
1093 ctrl_word, p_fcrb->remote_busy);
1094
1095 #if (L2CAP_ERTM_STATS == TRUE)
1096 p_ccb->fcrb.s_frames_rcvd[s_frame_type]++;
1097 #endif
1098
1099 if (ctrl_word & L2CAP_FCR_P_BIT) {
1100 p_fcrb->rej_sent = false; /* After checkpoint, we can send anoher REJ */
1101 p_fcrb->send_f_rsp = true; /* Set a flag in case an I-frame is pending */
1102 }
1103
1104 switch (s_frame_type) {
1105 case L2CAP_FCR_SUP_RR:
1106 remote_was_busy = p_fcrb->remote_busy;
1107 p_fcrb->remote_busy = false;
1108
1109 if ((ctrl_word & L2CAP_FCR_F_BIT) || (remote_was_busy))
1110 all_ok = retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS);
1111 break;
1112
1113 case L2CAP_FCR_SUP_REJ:
1114 p_fcrb->remote_busy = false;
1115 all_ok = retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS);
1116 break;
1117
1118 case L2CAP_FCR_SUP_RNR:
1119 p_fcrb->remote_busy = true;
1120 l2c_fcr_stop_timer(p_ccb);
1121 break;
1122
1123 case L2CAP_FCR_SUP_SREJ:
1124 p_fcrb->remote_busy = false;
1125 all_ok = retransmit_i_frames(
1126 p_ccb, (uint8_t)((ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >>
1127 L2CAP_FCR_REQ_SEQ_BITS_SHIFT));
1128 break;
1129 }
1130
1131 if (all_ok) {
1132 /* If polled, we need to respond with F-bit. Note, we may have sent a
1133 * I-frame with the F-bit */
1134 if (p_fcrb->send_f_rsp) {
1135 if (p_fcrb->srej_sent)
1136 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, L2CAP_FCR_F_BIT);
1137 else if (p_fcrb->local_busy)
1138 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, L2CAP_FCR_F_BIT);
1139 else
1140 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, L2CAP_FCR_F_BIT);
1141
1142 p_fcrb->send_f_rsp = false;
1143 }
1144 } else {
1145 L2CAP_TRACE_DEBUG("process_s_frame hit_max_retries");
1146 }
1147
1148 osi_free(p_buf);
1149 }
1150
1151 /*******************************************************************************
1152 *
1153 * Function process_i_frame
1154 *
1155 * Description Process an I frame
1156 *
1157 * Returns -
1158 *
1159 ******************************************************************************/
process_i_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word,bool delay_ack)1160 static void process_i_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf, uint16_t ctrl_word,
1161 bool delay_ack) {
1162 CHECK(p_ccb != NULL);
1163 CHECK(p_buf != NULL);
1164
1165 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1166 uint8_t tx_seq, num_lost, num_to_ack, next_srej;
1167
1168 /* If we were doing checkpoint recovery, first retransmit all unacked I-frames
1169 */
1170 if (ctrl_word & L2CAP_FCR_F_BIT) {
1171 if (!retransmit_i_frames(p_ccb, L2C_FCR_RETX_ALL_PKTS)) {
1172 osi_free(p_buf);
1173 return;
1174 }
1175 }
1176
1177 #if (L2CAP_ERTM_STATS == TRUE)
1178 p_ccb->fcrb.ertm_pkt_counts[1]++;
1179 p_ccb->fcrb.ertm_byte_counts[1] += p_buf->len;
1180 #endif
1181
1182 /* Extract the sequence number */
1183 tx_seq = (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1184
1185 /* If we have flow controlled the peer, ignore any bad I-frames from him */
1186 if ((tx_seq != p_fcrb->next_seq_expected) && (p_fcrb->local_busy)) {
1187 L2CAP_TRACE_WARNING("Dropping bad I-Frame since we flowed off, tx_seq:%u",
1188 tx_seq);
1189 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
1190 osi_free(p_buf);
1191 return;
1192 }
1193
1194 /* Check if tx-sequence is the expected one */
1195 if (tx_seq != p_fcrb->next_seq_expected) {
1196 num_lost = (tx_seq - p_fcrb->next_seq_expected) & L2CAP_FCR_SEQ_MODULO;
1197
1198 /* Is the frame a duplicate ? If so, just drop it */
1199 if (num_lost >= p_ccb->our_cfg.fcr.tx_win_sz) {
1200 /* Duplicate - simply drop it */
1201 L2CAP_TRACE_WARNING(
1202 "process_i_frame() Dropping Duplicate Frame tx_seq:%u ExpectedTxSeq "
1203 "%u",
1204 tx_seq, p_fcrb->next_seq_expected);
1205 osi_free(p_buf);
1206 } else {
1207 L2CAP_TRACE_WARNING(
1208 "process_i_frame() CID: 0x%04x Lost: %u tx_seq:%u ExpTxSeq %u "
1209 "Rej: %u SRej: %u",
1210 p_ccb->local_cid, num_lost, tx_seq, p_fcrb->next_seq_expected,
1211 p_fcrb->rej_sent, p_fcrb->srej_sent);
1212
1213 if (p_fcrb->srej_sent) {
1214 /* If SREJ sent, save the frame for later processing as long as it is in
1215 * sequence */
1216 next_srej =
1217 (((BT_HDR*)fixed_queue_try_peek_last(p_fcrb->srej_rcv_hold_q))
1218 ->layer_specific +
1219 1) &
1220 L2CAP_FCR_SEQ_MODULO;
1221
1222 if ((tx_seq == next_srej) &&
1223 (fixed_queue_length(p_fcrb->srej_rcv_hold_q) <
1224 p_ccb->our_cfg.fcr.tx_win_sz)) {
1225 /* If user gave us a pool for held rx buffers, use that */
1226 /* TODO: Could that happen? Get rid of this code. */
1227 if (p_ccb->ertm_info.fcr_rx_buf_size != L2CAP_FCR_RX_BUF_SIZE) {
1228 BT_HDR* p_buf2;
1229
1230 /* Adjust offset and len so that control word is copied */
1231 p_buf->offset -= L2CAP_FCR_OVERHEAD;
1232 p_buf->len += L2CAP_FCR_OVERHEAD;
1233
1234 p_buf2 = l2c_fcr_clone_buf(p_buf, p_buf->offset, p_buf->len);
1235
1236 if (p_buf2) {
1237 osi_free(p_buf);
1238 p_buf = p_buf2;
1239 }
1240 p_buf->offset += L2CAP_FCR_OVERHEAD;
1241 p_buf->len -= L2CAP_FCR_OVERHEAD;
1242 }
1243 L2CAP_TRACE_DEBUG(
1244 "process_i_frame() Lost: %u tx_seq:%u ExpTxSeq %u Rej: %u "
1245 "SRej1",
1246 num_lost, tx_seq, p_fcrb->next_seq_expected, p_fcrb->rej_sent);
1247
1248 p_buf->layer_specific = tx_seq;
1249 fixed_queue_enqueue(p_fcrb->srej_rcv_hold_q, p_buf);
1250 } else {
1251 L2CAP_TRACE_WARNING(
1252 "process_i_frame() CID: 0x%04x frame dropped in Srej Sent "
1253 "next_srej:%u hold_q.count:%u win_sz:%u",
1254 p_ccb->local_cid, next_srej,
1255 fixed_queue_length(p_fcrb->srej_rcv_hold_q),
1256 p_ccb->our_cfg.fcr.tx_win_sz);
1257
1258 p_fcrb->rej_after_srej = true;
1259 osi_free(p_buf);
1260 }
1261 } else if (p_fcrb->rej_sent) {
1262 L2CAP_TRACE_WARNING(
1263 "process_i_frame() CID: 0x%04x Lost: %u tx_seq:%u ExpTxSeq %u "
1264 "Rej: 1 SRej: %u",
1265 p_ccb->local_cid, num_lost, tx_seq, p_fcrb->next_seq_expected,
1266 p_fcrb->srej_sent);
1267
1268 /* If REJ sent, just drop the frame */
1269 osi_free(p_buf);
1270 } else {
1271 L2CAP_TRACE_DEBUG(
1272 "process_i_frame() CID: 0x%04x tx_seq:%u ExpTxSeq %u Rej: %u",
1273 p_ccb->local_cid, tx_seq, p_fcrb->next_seq_expected,
1274 p_fcrb->rej_sent);
1275
1276 /* If only one lost, we will send SREJ, otherwise we will send REJ */
1277 if (num_lost > 1) {
1278 osi_free(p_buf);
1279 p_fcrb->rej_sent = true;
1280 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_REJ, 0);
1281 } else {
1282 if (!fixed_queue_is_empty(p_fcrb->srej_rcv_hold_q)) {
1283 L2CAP_TRACE_ERROR(
1284 "process_i_frame() CID: 0x%04x sending SREJ tx_seq:%d "
1285 "hold_q.count:%u",
1286 p_ccb->local_cid, tx_seq,
1287 fixed_queue_length(p_fcrb->srej_rcv_hold_q));
1288 }
1289 p_buf->layer_specific = tx_seq;
1290 fixed_queue_enqueue(p_fcrb->srej_rcv_hold_q, p_buf);
1291 p_fcrb->srej_sent = true;
1292 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_SREJ, 0);
1293 }
1294 alarm_cancel(p_ccb->fcrb.ack_timer);
1295 }
1296 }
1297 return;
1298 }
1299
1300 /* Seq number is the next expected. Clear possible reject exception in case it
1301 * occured */
1302 p_fcrb->rej_sent = p_fcrb->srej_sent = false;
1303
1304 /* Adjust the next_seq, so that if the upper layer sends more data in the
1305 callback
1306 context, the received frame is acked by an I-frame. */
1307 p_fcrb->next_seq_expected = (tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
1308
1309 /* If any SAR problem in eRTM mode, spec says disconnect. */
1310 if (!do_sar_reassembly(p_ccb, p_buf, ctrl_word)) {
1311 L2CAP_TRACE_WARNING("process_i_frame() CID: 0x%04x reassembly failed",
1312 p_ccb->local_cid);
1313 l2cu_disconnect_chnl(p_ccb);
1314 return;
1315 }
1316
1317 /* RR optimization - if peer can still send us more, then start an ACK timer
1318 */
1319 num_to_ack = (p_fcrb->next_seq_expected - p_fcrb->last_ack_sent) &
1320 L2CAP_FCR_SEQ_MODULO;
1321
1322 if ((num_to_ack < p_ccb->fcrb.max_held_acks) && (!p_fcrb->local_busy))
1323 delay_ack = true;
1324
1325 /* We should neve never ack frame if we are not in OPEN state */
1326 if ((num_to_ack != 0) && p_ccb->in_use && (p_ccb->chnl_state == CST_OPEN)) {
1327 /* If no frames are awaiting transmission or are held, send an RR or RNR
1328 * S-frame for ack */
1329 if (delay_ack) {
1330 /* If it is the first I frame we did not ack, start ack timer */
1331 if (!alarm_is_scheduled(p_ccb->fcrb.ack_timer)) {
1332 alarm_set_on_mloop(p_ccb->fcrb.ack_timer, L2CAP_FCR_ACK_TIMEOUT_MS,
1333 l2c_fcrb_ack_timer_timeout, p_ccb);
1334 }
1335 } else if ((fixed_queue_is_empty(p_ccb->xmit_hold_q) ||
1336 l2c_fcr_is_flow_controlled(p_ccb)) &&
1337 fixed_queue_is_empty(p_ccb->fcrb.srej_rcv_hold_q)) {
1338 if (p_fcrb->local_busy)
1339 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RNR, 0);
1340 else
1341 l2c_fcr_send_S_frame(p_ccb, L2CAP_FCR_SUP_RR, 0);
1342 }
1343 }
1344 }
1345
1346 /*******************************************************************************
1347 *
1348 * Function process_stream_frame
1349 *
1350 * Description This function processes frames in streaming mode
1351 *
1352 * Returns -
1353 *
1354 ******************************************************************************/
process_stream_frame(tL2C_CCB * p_ccb,BT_HDR * p_buf)1355 static void process_stream_frame(tL2C_CCB* p_ccb, BT_HDR* p_buf) {
1356 CHECK(p_ccb != NULL);
1357 CHECK(p_buf != NULL);
1358
1359 uint16_t ctrl_word;
1360 uint16_t fcs;
1361 uint8_t* p;
1362 uint8_t tx_seq;
1363
1364 /* Verify FCS if using */
1365 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
1366 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len - L2CAP_FCS_LEN;
1367
1368 /* Extract and drop the FCS from the packet */
1369 STREAM_TO_UINT16(fcs, p);
1370 p_buf->len -= L2CAP_FCS_LEN;
1371
1372 if (l2c_fcr_rx_get_fcs(p_buf) != fcs) {
1373 L2CAP_TRACE_WARNING("Rx L2CAP PDU: CID: 0x%04x BAD FCS",
1374 p_ccb->local_cid);
1375 osi_free(p_buf);
1376 return;
1377 }
1378 }
1379
1380 /* Get the control word */
1381 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
1382
1383 STREAM_TO_UINT16(ctrl_word, p);
1384
1385 p_buf->len -= L2CAP_FCR_OVERHEAD;
1386 p_buf->offset += L2CAP_FCR_OVERHEAD;
1387
1388 /* Make sure it is an I-frame */
1389 if (ctrl_word & L2CAP_FCR_S_FRAME_BIT) {
1390 L2CAP_TRACE_WARNING(
1391 "Rx L2CAP PDU: CID: 0x%04x BAD S-frame in streaming mode ctrl_word: "
1392 "0x%04x",
1393 p_ccb->local_cid, ctrl_word);
1394 osi_free(p_buf);
1395 return;
1396 }
1397
1398 L2CAP_TRACE_EVENT(
1399 "L2CAP eRTM Rx I-frame: cid: 0x%04x Len: %u SAR: %-12s TxSeq: %u "
1400 "ReqSeq: %u F: %u",
1401 p_ccb->local_cid, p_buf->len,
1402 SAR_types[(ctrl_word & L2CAP_FCR_SAR_BITS) >> L2CAP_FCR_SAR_BITS_SHIFT],
1403 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT,
1404 (ctrl_word & L2CAP_FCR_REQ_SEQ_BITS) >> L2CAP_FCR_REQ_SEQ_BITS_SHIFT,
1405 (ctrl_word & L2CAP_FCR_F_BIT) >> L2CAP_FCR_F_BIT_SHIFT);
1406
1407 /* Extract the sequence number */
1408 tx_seq = (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1409
1410 /* Check if tx-sequence is the expected one */
1411 if (tx_seq != p_ccb->fcrb.next_seq_expected) {
1412 L2CAP_TRACE_WARNING(
1413 "Rx L2CAP PDU: CID: 0x%04x Lost frames Exp: %u Got: %u p_rx_sdu: "
1414 "0x%08x",
1415 p_ccb->local_cid, p_ccb->fcrb.next_seq_expected, tx_seq,
1416 p_ccb->fcrb.p_rx_sdu);
1417
1418 /* Lost one or more packets, so flush the SAR queue */
1419 osi_free_and_reset((void**)&p_ccb->fcrb.p_rx_sdu);
1420 }
1421
1422 p_ccb->fcrb.next_seq_expected = (tx_seq + 1) & L2CAP_FCR_SEQ_MODULO;
1423
1424 if (!do_sar_reassembly(p_ccb, p_buf, ctrl_word)) {
1425 /* Some sort of SAR error, so flush the SAR queue */
1426 osi_free_and_reset((void**)&p_ccb->fcrb.p_rx_sdu);
1427 }
1428 }
1429
1430 /*******************************************************************************
1431 *
1432 * Function do_sar_reassembly
1433 *
1434 * Description Process SAR bits and re-assemble frame
1435 *
1436 * Returns true if all OK, else false
1437 *
1438 ******************************************************************************/
do_sar_reassembly(tL2C_CCB * p_ccb,BT_HDR * p_buf,uint16_t ctrl_word)1439 static bool do_sar_reassembly(tL2C_CCB* p_ccb, BT_HDR* p_buf,
1440 uint16_t ctrl_word) {
1441 CHECK(p_ccb != NULL);
1442 CHECK(p_buf != NULL);
1443
1444 tL2C_FCRB* p_fcrb = &p_ccb->fcrb;
1445 uint16_t sar_type = ctrl_word & L2CAP_FCR_SEG_BITS;
1446 bool packet_ok = true;
1447 uint8_t* p;
1448
1449 /* Check if the SAR state is correct */
1450 if ((sar_type == L2CAP_FCR_UNSEG_SDU) || (sar_type == L2CAP_FCR_START_SDU)) {
1451 if (p_fcrb->p_rx_sdu != NULL) {
1452 L2CAP_TRACE_WARNING(
1453 "SAR - got unexpected unsegmented or start SDU Expected len: %u "
1454 "Got so far: %u",
1455 p_fcrb->rx_sdu_len, p_fcrb->p_rx_sdu->len);
1456
1457 packet_ok = false;
1458 }
1459 /* Check the length of the packet */
1460 if ((sar_type == L2CAP_FCR_START_SDU) &&
1461 (p_buf->len < L2CAP_SDU_LEN_OVERHEAD)) {
1462 L2CAP_TRACE_WARNING("SAR start packet too short: %u", p_buf->len);
1463 packet_ok = false;
1464 }
1465 } else {
1466 if (p_fcrb->p_rx_sdu == NULL) {
1467 L2CAP_TRACE_WARNING("SAR - got unexpected cont or end SDU");
1468 packet_ok = false;
1469 }
1470 }
1471
1472 if ((packet_ok) && (sar_type != L2CAP_FCR_UNSEG_SDU)) {
1473 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset;
1474
1475 /* For start SDU packet, extract the SDU length */
1476 if (sar_type == L2CAP_FCR_START_SDU) {
1477 /* Get the SDU length */
1478 STREAM_TO_UINT16(p_fcrb->rx_sdu_len, p);
1479 p_buf->offset += 2;
1480 p_buf->len -= 2;
1481
1482 if (p_fcrb->rx_sdu_len > p_ccb->max_rx_mtu) {
1483 L2CAP_TRACE_WARNING("SAR - SDU len: %u larger than MTU: %u",
1484 p_fcrb->rx_sdu_len, p_fcrb->rx_sdu_len);
1485 packet_ok = false;
1486 } else {
1487 p_fcrb->p_rx_sdu = (BT_HDR*)osi_malloc(
1488 BT_HDR_SIZE + OBX_BUF_MIN_OFFSET + p_fcrb->rx_sdu_len);
1489 p_fcrb->p_rx_sdu->offset = OBX_BUF_MIN_OFFSET;
1490 p_fcrb->p_rx_sdu->len = 0;
1491 }
1492 }
1493
1494 if (packet_ok) {
1495 if ((p_fcrb->p_rx_sdu->len + p_buf->len) > p_fcrb->rx_sdu_len) {
1496 L2CAP_TRACE_ERROR(
1497 "SAR - SDU len exceeded Type: %u Lengths: %u %u %u", sar_type,
1498 p_fcrb->p_rx_sdu->len, p_buf->len, p_fcrb->rx_sdu_len);
1499 packet_ok = false;
1500 } else if ((sar_type == L2CAP_FCR_END_SDU) &&
1501 ((p_fcrb->p_rx_sdu->len + p_buf->len) != p_fcrb->rx_sdu_len)) {
1502 L2CAP_TRACE_WARNING("SAR - SDU end rcvd but SDU incomplete: %u %u %u",
1503 p_fcrb->p_rx_sdu->len, p_buf->len,
1504 p_fcrb->rx_sdu_len);
1505 packet_ok = false;
1506 } else {
1507 memcpy(((uint8_t*)(p_fcrb->p_rx_sdu + 1)) + p_fcrb->p_rx_sdu->offset +
1508 p_fcrb->p_rx_sdu->len,
1509 p, p_buf->len);
1510
1511 p_fcrb->p_rx_sdu->len += p_buf->len;
1512
1513 osi_free(p_buf);
1514 p_buf = NULL;
1515
1516 if (sar_type == L2CAP_FCR_END_SDU) {
1517 p_buf = p_fcrb->p_rx_sdu;
1518 p_fcrb->p_rx_sdu = NULL;
1519 }
1520 }
1521 }
1522 }
1523
1524 if (!packet_ok) {
1525 osi_free(p_buf);
1526 } else if (p_buf != NULL) {
1527 #if (L2CAP_NUM_FIXED_CHNLS > 0)
1528 if (p_ccb->local_cid < L2CAP_BASE_APPL_CID &&
1529 (p_ccb->local_cid >= L2CAP_FIRST_FIXED_CHNL &&
1530 p_ccb->local_cid <= L2CAP_LAST_FIXED_CHNL)) {
1531 if (l2cb.fixed_reg[p_ccb->local_cid - L2CAP_FIRST_FIXED_CHNL]
1532 .pL2CA_FixedData_Cb)
1533 (*l2cb.fixed_reg[p_ccb->local_cid - L2CAP_FIRST_FIXED_CHNL]
1534 .pL2CA_FixedData_Cb)(p_ccb->local_cid,
1535 p_ccb->p_lcb->remote_bd_addr, p_buf);
1536 } else
1537 #endif
1538 l2c_csm_execute(p_ccb, L2CEVT_L2CAP_DATA, p_buf);
1539 }
1540
1541 return (packet_ok);
1542 }
1543
1544 /*******************************************************************************
1545 *
1546 * Function retransmit_i_frames
1547 *
1548 * Description This function retransmits i-frames awaiting acks.
1549 *
1550 * Returns bool - true if retransmitted
1551 *
1552 ******************************************************************************/
retransmit_i_frames(tL2C_CCB * p_ccb,uint8_t tx_seq)1553 static bool retransmit_i_frames(tL2C_CCB* p_ccb, uint8_t tx_seq) {
1554 CHECK(p_ccb != NULL);
1555
1556 BT_HDR* p_buf = NULL;
1557 uint8_t* p;
1558 uint8_t buf_seq;
1559 uint16_t ctrl_word;
1560
1561 if ((!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q)) &&
1562 (p_ccb->peer_cfg.fcr.max_transmit != 0) &&
1563 (p_ccb->fcrb.num_tries >= p_ccb->peer_cfg.fcr.max_transmit)) {
1564 L2CAP_TRACE_EVENT(
1565 "Max Tries Exceeded: (last_acq: %d CID: 0x%04x num_tries: %u (max: "
1566 "%u) ack_q_count: %u",
1567 p_ccb->fcrb.last_rx_ack, p_ccb->local_cid, p_ccb->fcrb.num_tries,
1568 p_ccb->peer_cfg.fcr.max_transmit,
1569 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
1570
1571 l2cu_disconnect_chnl(p_ccb);
1572 return (false);
1573 }
1574
1575 /* tx_seq indicates whether to retransmit a specific sequence or all (if ==
1576 * L2C_FCR_RETX_ALL_PKTS) */
1577 list_t* list_ack = NULL;
1578 const list_node_t* node_ack = NULL;
1579 if (!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q)) {
1580 list_ack = fixed_queue_get_list(p_ccb->fcrb.waiting_for_ack_q);
1581 node_ack = list_begin(list_ack);
1582 }
1583 if (tx_seq != L2C_FCR_RETX_ALL_PKTS) {
1584 /* If sending only one, the sequence number tells us which one. Look for it.
1585 */
1586 if (list_ack != NULL) {
1587 for (; node_ack != list_end(list_ack); node_ack = list_next(node_ack)) {
1588 p_buf = (BT_HDR*)list_node(node_ack);
1589 /* Get the old control word */
1590 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + L2CAP_PKT_OVERHEAD;
1591
1592 STREAM_TO_UINT16(ctrl_word, p);
1593
1594 buf_seq =
1595 (ctrl_word & L2CAP_FCR_TX_SEQ_BITS) >> L2CAP_FCR_TX_SEQ_BITS_SHIFT;
1596
1597 L2CAP_TRACE_DEBUG(
1598 "retransmit_i_frames() cur seq: %u looking for: %u", buf_seq,
1599 tx_seq);
1600
1601 if (tx_seq == buf_seq) break;
1602 }
1603 }
1604
1605 if (!p_buf) {
1606 L2CAP_TRACE_ERROR("retransmit_i_frames() UNKNOWN seq: %u q_count: %u",
1607 tx_seq,
1608 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q));
1609 return (true);
1610 }
1611 } else {
1612 // Iterate though list and flush the amount requested from
1613 // the transmit data queue that satisfy the layer and event conditions.
1614 for (list_node_t* node_tmp = list_begin(p_ccb->p_lcb->link_xmit_data_q);
1615 node_tmp != list_end(p_ccb->p_lcb->link_xmit_data_q);) {
1616 BT_HDR* p_tmp = (BT_HDR*)list_node(node_tmp);
1617 node_tmp = list_next(node_tmp);
1618
1619 /* Do not flush other CIDs or partial segments */
1620 if ((p_tmp->layer_specific == 0) && (p_tmp->event == p_ccb->local_cid)) {
1621 list_remove(p_ccb->p_lcb->link_xmit_data_q, p_tmp);
1622 osi_free(p_tmp);
1623 }
1624 }
1625
1626 /* Also flush our retransmission queue */
1627 while (!fixed_queue_is_empty(p_ccb->fcrb.retrans_q))
1628 osi_free(fixed_queue_try_dequeue(p_ccb->fcrb.retrans_q));
1629
1630 if (list_ack != NULL) node_ack = list_begin(list_ack);
1631 }
1632
1633 if (list_ack != NULL) {
1634 while (node_ack != list_end(list_ack)) {
1635 p_buf = (BT_HDR*)list_node(node_ack);
1636 node_ack = list_next(node_ack);
1637
1638 BT_HDR* p_buf2 = l2c_fcr_clone_buf(p_buf, p_buf->offset, p_buf->len);
1639 if (p_buf2) {
1640 p_buf2->layer_specific = p_buf->layer_specific;
1641
1642 fixed_queue_enqueue(p_ccb->fcrb.retrans_q, p_buf2);
1643 }
1644
1645 if ((tx_seq != L2C_FCR_RETX_ALL_PKTS) || (p_buf2 == NULL)) break;
1646 }
1647 }
1648
1649 l2c_link_check_send_pkts(p_ccb->p_lcb, NULL, NULL);
1650
1651 if (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q)) {
1652 p_ccb->fcrb.num_tries++;
1653 l2c_fcr_start_timer(p_ccb);
1654 }
1655
1656 return (true);
1657 }
1658
1659 /*******************************************************************************
1660 *
1661 * Function l2c_fcr_get_next_xmit_sdu_seg
1662 *
1663 * Description Get the next SDU segment to transmit.
1664 *
1665 * Returns pointer to buffer with segment or NULL
1666 *
1667 ******************************************************************************/
l2c_fcr_get_next_xmit_sdu_seg(tL2C_CCB * p_ccb,uint16_t max_packet_length)1668 BT_HDR* l2c_fcr_get_next_xmit_sdu_seg(tL2C_CCB* p_ccb,
1669 uint16_t max_packet_length) {
1670 CHECK(p_ccb != NULL);
1671
1672 bool first_seg = false, /* The segment is the first part of data */
1673 mid_seg = false, /* The segment is the middle part of data */
1674 last_seg = false; /* The segment is the last part of data */
1675 uint16_t sdu_len = 0;
1676 BT_HDR *p_buf, *p_xmit;
1677 uint8_t* p;
1678 uint16_t max_pdu = p_ccb->tx_mps /* Needed? - L2CAP_MAX_HEADER_FCS*/;
1679
1680 /* If there is anything in the retransmit queue, that goes first
1681 */
1682 p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->fcrb.retrans_q);
1683 if (p_buf != NULL) {
1684 /* Update Rx Seq and FCS if we acked some packets while this one was queued
1685 */
1686 prepare_I_frame(p_ccb, p_buf, true);
1687
1688 p_buf->event = p_ccb->local_cid;
1689
1690 #if (L2CAP_ERTM_STATS == TRUE)
1691 p_ccb->fcrb.pkts_retransmitted++;
1692 p_ccb->fcrb.ertm_pkt_counts[0]++;
1693 p_ccb->fcrb.ertm_byte_counts[0] += (p_buf->len - 8);
1694 #endif
1695 return (p_buf);
1696 }
1697
1698 /* For BD/EDR controller, max_packet_length is set to 0 */
1699 /* For AMP controller, max_packet_length is set by available blocks */
1700 if ((max_packet_length > L2CAP_MAX_HEADER_FCS) &&
1701 (max_pdu + L2CAP_MAX_HEADER_FCS > max_packet_length)) {
1702 max_pdu = max_packet_length - L2CAP_MAX_HEADER_FCS;
1703 }
1704
1705 p_buf = (BT_HDR*)fixed_queue_try_peek_first(p_ccb->xmit_hold_q);
1706
1707 /* If there is more data than the MPS, it requires segmentation */
1708 if (p_buf->len > max_pdu) {
1709 /* We are using the "event" field to tell is if we already started
1710 * segmentation */
1711 if (p_buf->event == 0) {
1712 first_seg = true;
1713 sdu_len = p_buf->len;
1714 } else
1715 mid_seg = true;
1716
1717 /* Get a new buffer and copy the data that can be sent in a PDU */
1718 p_xmit = l2c_fcr_clone_buf(p_buf, L2CAP_MIN_OFFSET + L2CAP_SDU_LEN_OFFSET,
1719 max_pdu);
1720
1721 if (p_xmit != NULL) {
1722 p_buf->event = p_ccb->local_cid;
1723 p_xmit->event = p_ccb->local_cid;
1724
1725 p_buf->len -= max_pdu;
1726 p_buf->offset += max_pdu;
1727
1728 /* copy PBF setting */
1729 p_xmit->layer_specific = p_buf->layer_specific;
1730 } else /* Should never happen if the application has configured buffers
1731 correctly */
1732 {
1733 L2CAP_TRACE_ERROR(
1734 "L2CAP - cannot get buffer for segmentation, max_pdu: %u", max_pdu);
1735 return (NULL);
1736 }
1737 } else /* Use the original buffer if no segmentation, or the last segment */
1738 {
1739 p_xmit = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q);
1740
1741 if (p_xmit->event != 0) last_seg = true;
1742
1743 p_xmit->event = p_ccb->local_cid;
1744 }
1745
1746 /* Step back to add the L2CAP headers */
1747 p_xmit->offset -= (L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD);
1748 p_xmit->len += L2CAP_PKT_OVERHEAD + L2CAP_FCR_OVERHEAD;
1749
1750 if (first_seg) {
1751 p_xmit->offset -= L2CAP_SDU_LEN_OVERHEAD;
1752 p_xmit->len += L2CAP_SDU_LEN_OVERHEAD;
1753 }
1754
1755 /* Set the pointer to the beginning of the data */
1756 p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1757
1758 /* Now the L2CAP header */
1759
1760 /* Note: if FCS has to be included then the length is recalculated later */
1761 UINT16_TO_STREAM(p, p_xmit->len - L2CAP_PKT_OVERHEAD);
1762
1763 UINT16_TO_STREAM(p, p_ccb->remote_cid);
1764
1765 if (first_seg) {
1766 /* Skip control word and add SDU length */
1767 p += 2;
1768 UINT16_TO_STREAM(p, sdu_len);
1769
1770 /* We will store the SAR type in layer-specific */
1771 /* layer_specific is shared with flushable flag(bits 0-1), don't clear it */
1772 p_xmit->layer_specific |= L2CAP_FCR_START_SDU;
1773
1774 first_seg = false;
1775 } else if (mid_seg)
1776 p_xmit->layer_specific |= L2CAP_FCR_CONT_SDU;
1777 else if (last_seg)
1778 p_xmit->layer_specific |= L2CAP_FCR_END_SDU;
1779 else
1780 p_xmit->layer_specific |= L2CAP_FCR_UNSEG_SDU;
1781
1782 prepare_I_frame(p_ccb, p_xmit, false);
1783
1784 if (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) {
1785 BT_HDR* p_wack =
1786 l2c_fcr_clone_buf(p_xmit, HCI_DATA_PREAMBLE_SIZE, p_xmit->len);
1787
1788 if (!p_wack) {
1789 L2CAP_TRACE_ERROR(
1790 "L2CAP - no buffer for xmit cloning, CID: 0x%04x Length: %u",
1791 p_ccb->local_cid, p_xmit->len);
1792
1793 /* We will not save the FCS in case we reconfigure and change options */
1794 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) p_xmit->len -= L2CAP_FCS_LEN;
1795
1796 /* Pretend we sent it and it got lost */
1797 fixed_queue_enqueue(p_ccb->fcrb.waiting_for_ack_q, p_xmit);
1798 return (NULL);
1799 } else {
1800 #if (L2CAP_ERTM_STATS == TRUE)
1801 /* set timestamp at the end of tx I-frame to get acking delay */
1802 /*
1803 * NOTE: Here we assume the allocate buffer is large enough
1804 * to include extra 4 octets at the end.
1805 */
1806 p = ((uint8_t*)(p_wack + 1)) + p_wack->offset + p_wack->len;
1807 UINT32_TO_STREAM(p, time_get_os_boottime_ms());
1808 #endif
1809 /* We will not save the FCS in case we reconfigure and change options */
1810 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) p_wack->len -= L2CAP_FCS_LEN;
1811
1812 p_wack->layer_specific = p_xmit->layer_specific;
1813 fixed_queue_enqueue(p_ccb->fcrb.waiting_for_ack_q, p_wack);
1814 }
1815
1816 #if (L2CAP_ERTM_STATS == TRUE)
1817 p_ccb->fcrb.ertm_pkt_counts[0]++;
1818 p_ccb->fcrb.ertm_byte_counts[0] += (p_xmit->len - 8);
1819 #endif
1820 }
1821
1822 return (p_xmit);
1823 }
1824
1825 /** Get the next PDU to transmit for LE connection oriented channel. Returns
1826 * pointer to buffer with PDU. |last_piece_of_sdu| will be set to true, if
1827 * returned PDU is last piece from this SDU.*/
l2c_lcc_get_next_xmit_sdu_seg(tL2C_CCB * p_ccb,bool * last_piece_of_sdu)1828 BT_HDR* l2c_lcc_get_next_xmit_sdu_seg(tL2C_CCB* p_ccb,
1829 bool* last_piece_of_sdu) {
1830 uint16_t max_pdu = p_ccb->peer_conn_cfg.mps - 4 /* Length and CID */;
1831
1832 BT_HDR* p_buf = (BT_HDR*)fixed_queue_try_peek_first(p_ccb->xmit_hold_q);
1833 bool first_pdu = (p_buf->event == 0) ? true : false;
1834
1835 uint16_t no_of_bytes_to_send = std::min(
1836 p_buf->len,
1837 (uint16_t)(first_pdu ? (max_pdu - L2CAP_LCC_SDU_LENGTH) : max_pdu));
1838 bool last_pdu = (no_of_bytes_to_send == p_buf->len);
1839
1840 /* Get a new buffer and copy the data that can be sent in a PDU */
1841 BT_HDR* p_xmit =
1842 l2c_fcr_clone_buf(p_buf, first_pdu ? L2CAP_LCC_OFFSET : L2CAP_MIN_OFFSET,
1843 no_of_bytes_to_send);
1844
1845 p_buf->event = p_ccb->local_cid;
1846 p_xmit->event = p_ccb->local_cid;
1847
1848 if (first_pdu) {
1849 p_xmit->offset -= L2CAP_LCC_SDU_LENGTH; /* for writing the SDU length. */
1850 uint8_t* p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1851 UINT16_TO_STREAM(p, p_buf->len);
1852 p_xmit->len += L2CAP_LCC_SDU_LENGTH;
1853 }
1854
1855 p_buf->len -= no_of_bytes_to_send;
1856 p_buf->offset += no_of_bytes_to_send;
1857
1858 /* copy PBF setting */
1859 p_xmit->layer_specific = p_buf->layer_specific;
1860
1861 if (last_piece_of_sdu) *last_piece_of_sdu = last_pdu;
1862
1863 if (last_pdu) {
1864 p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q);
1865 osi_free(p_buf);
1866 }
1867
1868 /* Step back to add the L2CAP headers */
1869 p_xmit->offset -= L2CAP_PKT_OVERHEAD;
1870 p_xmit->len += L2CAP_PKT_OVERHEAD;
1871
1872 /* Set the pointer to the beginning of the data */
1873 uint8_t* p = (uint8_t*)(p_xmit + 1) + p_xmit->offset;
1874
1875 /* Note: if FCS has to be included then the length is recalculated later */
1876 UINT16_TO_STREAM(p, p_xmit->len - L2CAP_PKT_OVERHEAD);
1877 UINT16_TO_STREAM(p, p_ccb->remote_cid);
1878 return (p_xmit);
1879 }
1880
1881 /*******************************************************************************
1882 * Configuration negotiation functions
1883 *
1884 * The following functions are used in negotiating channel modes during
1885 * configuration
1886 ******************************************************************************/
1887
1888 /*******************************************************************************
1889 *
1890 * Function l2c_fcr_chk_chan_modes
1891 *
1892 * Description Validates and adjusts if necessary, the FCR options
1893 * based on remote EXT features.
1894 *
1895 * Note: This assumes peer EXT Features have been received.
1896 * Basic mode is used if FCR Options have not been received
1897 *
1898 * Returns uint8_t - nonzero if can continue, '0' if no compatible
1899 * channels
1900 *
1901 ******************************************************************************/
l2c_fcr_chk_chan_modes(tL2C_CCB * p_ccb)1902 uint8_t l2c_fcr_chk_chan_modes(tL2C_CCB* p_ccb) {
1903 CHECK(p_ccb != NULL);
1904
1905 /* Remove nonbasic options that the peer does not support */
1906 if (!(p_ccb->p_lcb->peer_ext_fea & L2CAP_EXTFEA_ENH_RETRANS))
1907 p_ccb->ertm_info.allowed_modes &= ~L2CAP_FCR_CHAN_OPT_ERTM;
1908
1909 if (!(p_ccb->p_lcb->peer_ext_fea & L2CAP_EXTFEA_STREAM_MODE))
1910 p_ccb->ertm_info.allowed_modes &= ~L2CAP_FCR_CHAN_OPT_STREAM;
1911
1912 /* At least one type needs to be set (Basic, ERTM, STM) to continue */
1913 if (!p_ccb->ertm_info.allowed_modes) {
1914 L2CAP_TRACE_WARNING(
1915 "L2CAP - Peer does not support our desired channel types");
1916 }
1917
1918 return (p_ccb->ertm_info.allowed_modes);
1919 }
1920
1921 /*******************************************************************************
1922 *
1923 * Function l2c_fcr_adj_our_req_options
1924 *
1925 * Description Validates and sets up the FCR options passed in from
1926 * L2CA_ConfigReq based on remote device's features.
1927 *
1928 * Returns true if no errors, Otherwise false
1929 *
1930 ******************************************************************************/
l2c_fcr_adj_our_req_options(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)1931 bool l2c_fcr_adj_our_req_options(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
1932 CHECK(p_ccb != NULL);
1933 CHECK(p_cfg != NULL);
1934
1935 tL2CAP_FCR_OPTS* p_fcr = &p_cfg->fcr;
1936
1937 if (p_fcr->mode != p_ccb->ertm_info.preferred_mode) {
1938 L2CAP_TRACE_WARNING(
1939 "l2c_fcr_adj_our_req_options - preferred_mode (%d), does not match "
1940 "mode (%d)",
1941 p_ccb->ertm_info.preferred_mode, p_fcr->mode);
1942
1943 /* The preferred mode is passed in through tL2CAP_ERTM_INFO, so override
1944 * this one */
1945 p_fcr->mode = p_ccb->ertm_info.preferred_mode;
1946 }
1947
1948 /* If upper layer did not request eRTM mode, BASIC must be used */
1949 if (p_ccb->ertm_info.allowed_modes == L2CAP_FCR_CHAN_OPT_BASIC) {
1950 if (p_cfg->fcr_present && p_fcr->mode != L2CAP_FCR_BASIC_MODE) {
1951 L2CAP_TRACE_WARNING(
1952 "l2c_fcr_adj_our_req_options (mode %d): ERROR: No FCR options set "
1953 "using BASIC mode",
1954 p_fcr->mode);
1955 }
1956 p_fcr->mode = L2CAP_FCR_BASIC_MODE;
1957 }
1958
1959 /* Process the FCR options if initial channel bring-up (not a reconfig
1960 *request)
1961 ** Determine initial channel mode to try based on our options and remote's
1962 *features
1963 */
1964 if (p_cfg->fcr_present && !(p_ccb->config_done & RECONFIG_FLAG)) {
1965 /* We need to have at least one mode type common with the peer */
1966 if (!l2c_fcr_chk_chan_modes(p_ccb)) {
1967 /* Two channels have incompatible supported types */
1968 l2cu_disconnect_chnl(p_ccb);
1969 return (false);
1970 }
1971
1972 /* Basic is the only common channel mode between the two devices */
1973 else if (p_ccb->ertm_info.allowed_modes == L2CAP_FCR_CHAN_OPT_BASIC) {
1974 /* We only want to try Basic, so bypass sending the FCR options entirely
1975 */
1976 p_cfg->fcr_present = false;
1977 p_cfg->fcs_present = false; /* Illegal to use FCS option in basic mode */
1978 p_cfg->ext_flow_spec_present =
1979 false; /* Illegal to use extended flow spec in basic mode */
1980 }
1981
1982 /* We have at least one non-basic mode available
1983 * Override mode from available mode options based on preference, if needed
1984 */
1985 else {
1986 /* If peer does not support STREAMING, try ERTM */
1987 if (p_fcr->mode == L2CAP_FCR_STREAM_MODE &&
1988 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_STREAM)) {
1989 L2CAP_TRACE_DEBUG(
1990 "L2C CFG: mode is STREAM, but peer does not support; Try ERTM");
1991 p_fcr->mode = L2CAP_FCR_ERTM_MODE;
1992 }
1993
1994 /* If peer does not support ERTM, try BASIC (will support this if made it
1995 * here in the code) */
1996 if (p_fcr->mode == L2CAP_FCR_ERTM_MODE &&
1997 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
1998 L2CAP_TRACE_DEBUG(
1999 "L2C CFG: mode is ERTM, but peer does not support; Try BASIC");
2000 p_fcr->mode = L2CAP_FCR_BASIC_MODE;
2001 }
2002 }
2003
2004 if (p_fcr->mode != L2CAP_FCR_BASIC_MODE) {
2005 /* MTU must be smaller than buffer size */
2006 if ((p_cfg->mtu_present) && (p_cfg->mtu > p_ccb->max_rx_mtu)) {
2007 L2CAP_TRACE_WARNING("L2CAP - MTU: %u larger than buf size: %u",
2008 p_cfg->mtu, p_ccb->max_rx_mtu);
2009 return (false);
2010 }
2011
2012 /* application want to use the default MPS */
2013 if (p_fcr->mps == L2CAP_DEFAULT_ERM_MPS) {
2014 p_fcr->mps = L2CAP_MPS_OVER_BR_EDR;
2015 }
2016 /* MPS must be less than MTU */
2017 else if (p_fcr->mps > p_ccb->max_rx_mtu) {
2018 L2CAP_TRACE_WARNING("L2CAP - MPS %u invalid MTU: %u", p_fcr->mps,
2019 p_ccb->max_rx_mtu);
2020 return (false);
2021 }
2022
2023 /* We always initially read into the HCI buffer pool, so make sure it fits
2024 */
2025 if (p_fcr->mps > (L2CAP_MTU_SIZE - L2CAP_MAX_HEADER_FCS))
2026 p_fcr->mps = L2CAP_MTU_SIZE - L2CAP_MAX_HEADER_FCS;
2027 } else {
2028 p_cfg->fcs_present = false; /* Illegal to use FCS option in basic mode */
2029 p_cfg->ext_flow_spec_present =
2030 false; /* Illegal to use extended flow spec in basic mode */
2031 }
2032
2033 p_ccb->our_cfg.fcr = *p_fcr;
2034 } else /* Not sure how to send a reconfiguration(??) should fcr be included?
2035 */
2036 {
2037 p_ccb->our_cfg.fcr_present = false;
2038 }
2039
2040 return (true);
2041 }
2042
2043 /*******************************************************************************
2044 *
2045 * Function l2c_fcr_adj_monitor_retran_timeout
2046 *
2047 * Description Overrides monitor/retrans timer value based on controller
2048 *
2049 * Returns None
2050 *
2051 ******************************************************************************/
l2c_fcr_adj_monitor_retran_timeout(tL2C_CCB * p_ccb)2052 void l2c_fcr_adj_monitor_retran_timeout(tL2C_CCB* p_ccb) {
2053 CHECK(p_ccb != NULL);
2054
2055 /* adjust our monitor/retran timeout */
2056 if (p_ccb->out_cfg_fcr_present) {
2057 /*
2058 ** if we requestd ERTM or accepted ERTM
2059 ** We may accept ERTM even if we didn't request ERTM, in case of requesting
2060 *STREAM
2061 */
2062 if ((p_ccb->our_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) ||
2063 (p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE)) {
2064 /* upper layer setting is ignored */
2065 p_ccb->our_cfg.fcr.mon_tout = L2CAP_MIN_MONITOR_TOUT;
2066 p_ccb->our_cfg.fcr.rtrans_tout = L2CAP_MIN_RETRANS_TOUT;
2067 } else {
2068 p_ccb->our_cfg.fcr.mon_tout = 0;
2069 p_ccb->our_cfg.fcr.rtrans_tout = 0;
2070 }
2071
2072 L2CAP_TRACE_DEBUG(
2073 "l2c_fcr_adj_monitor_retran_timeout: mon_tout:%d, rtrans_tout:%d",
2074 p_ccb->our_cfg.fcr.mon_tout, p_ccb->our_cfg.fcr.rtrans_tout);
2075 }
2076 }
2077 /*******************************************************************************
2078 *
2079 * Function l2c_fcr_adj_our_rsp_options
2080 *
2081 * Description Overrides any neccesary FCR options passed in from
2082 * L2CA_ConfigRsp based on our FCR options.
2083 * Only makes adjustments if channel is in ERTM mode.
2084 *
2085 * Returns None
2086 *
2087 ******************************************************************************/
l2c_fcr_adj_our_rsp_options(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2088 void l2c_fcr_adj_our_rsp_options(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2089 CHECK(p_ccb != NULL);
2090 CHECK(p_cfg != NULL);
2091
2092 /* adjust our monitor/retran timeout */
2093 l2c_fcr_adj_monitor_retran_timeout(p_ccb);
2094
2095 p_cfg->fcr_present = p_ccb->out_cfg_fcr_present;
2096
2097 if (p_cfg->fcr_present) {
2098 /* Temporary - until a better algorithm is implemented */
2099 /* If peer's tx_wnd_sz requires too many buffers for us to support, then
2100 * adjust it. For now, respond with our own tx_wnd_sz. */
2101 /* Note: peer is not guaranteed to obey our adjustment */
2102 if (p_ccb->peer_cfg.fcr.tx_win_sz > p_ccb->our_cfg.fcr.tx_win_sz) {
2103 L2CAP_TRACE_DEBUG("%s: adjusting requested tx_win_sz from %i to %i",
2104 __func__, p_ccb->peer_cfg.fcr.tx_win_sz,
2105 p_ccb->our_cfg.fcr.tx_win_sz);
2106 p_ccb->peer_cfg.fcr.tx_win_sz = p_ccb->our_cfg.fcr.tx_win_sz;
2107 }
2108
2109 p_cfg->fcr.mode = p_ccb->peer_cfg.fcr.mode;
2110 p_cfg->fcr.tx_win_sz = p_ccb->peer_cfg.fcr.tx_win_sz;
2111 p_cfg->fcr.max_transmit = p_ccb->peer_cfg.fcr.max_transmit;
2112 p_cfg->fcr.mps = p_ccb->peer_cfg.fcr.mps;
2113 p_cfg->fcr.rtrans_tout = p_ccb->our_cfg.fcr.rtrans_tout;
2114 p_cfg->fcr.mon_tout = p_ccb->our_cfg.fcr.mon_tout;
2115 }
2116 }
2117
2118 /*******************************************************************************
2119 *
2120 * Function l2c_fcr_renegotiate_chan
2121 *
2122 * Description Called upon unsuccessful peer response to config request.
2123 * If the error is because of the channel mode, it will try
2124 * to resend using another supported optional channel.
2125 *
2126 * Returns true if resent configuration, False if channel matches or
2127 * cannot match.
2128 *
2129 ******************************************************************************/
l2c_fcr_renegotiate_chan(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2130 bool l2c_fcr_renegotiate_chan(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2131 CHECK(p_ccb != NULL);
2132 CHECK(p_cfg != NULL);
2133
2134 uint8_t peer_mode = p_ccb->our_cfg.fcr.mode;
2135 bool can_renegotiate;
2136
2137 /* Skip if this is a reconfiguration from OPEN STATE or if FCR is not returned
2138 */
2139 if (!p_cfg->fcr_present || (p_ccb->config_done & RECONFIG_FLAG))
2140 return (false);
2141
2142 /* Only retry if there are more channel options to try */
2143 if (p_cfg->result == L2CAP_CFG_UNACCEPTABLE_PARAMS) {
2144 peer_mode = (p_cfg->fcr_present) ? p_cfg->fcr.mode : L2CAP_FCR_BASIC_MODE;
2145
2146 if (p_ccb->our_cfg.fcr.mode != peer_mode) {
2147 if ((--p_ccb->fcr_cfg_tries) == 0) {
2148 p_cfg->result = L2CAP_CFG_FAILED_NO_REASON;
2149 L2CAP_TRACE_WARNING("l2c_fcr_renegotiate_chan (Max retries exceeded)");
2150 }
2151
2152 can_renegotiate = false;
2153
2154 /* Try another supported mode if available based on our last attempted
2155 * channel */
2156 switch (p_ccb->our_cfg.fcr.mode) {
2157 /* Our Streaming mode request was unnacceptable; try ERTM or Basic */
2158 case L2CAP_FCR_STREAM_MODE:
2159 /* Peer wants ERTM and we support it */
2160 if ((peer_mode == L2CAP_FCR_ERTM_MODE) &&
2161 (p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
2162 L2CAP_TRACE_DEBUG("l2c_fcr_renegotiate_chan(Trying ERTM)");
2163 p_ccb->our_cfg.fcr.mode = L2CAP_FCR_ERTM_MODE;
2164 can_renegotiate = true;
2165 } else /* Falls through */
2166
2167 case L2CAP_FCR_ERTM_MODE: {
2168 /* We can try basic for any other peer mode if we support it */
2169 if (p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_BASIC) {
2170 L2CAP_TRACE_DEBUG("l2c_fcr_renegotiate_chan(Trying Basic)");
2171 can_renegotiate = true;
2172 p_ccb->our_cfg.fcr.mode = L2CAP_FCR_BASIC_MODE;
2173 }
2174 } break;
2175
2176 default:
2177 /* All other scenarios cannot be renegotiated */
2178 break;
2179 }
2180
2181 if (can_renegotiate) {
2182 p_ccb->our_cfg.fcr_present = true;
2183
2184 if (p_ccb->our_cfg.fcr.mode == L2CAP_FCR_BASIC_MODE) {
2185 p_ccb->our_cfg.fcs_present = false;
2186 p_ccb->our_cfg.ext_flow_spec_present = false;
2187
2188 /* Basic Mode uses ACL Data Pool, make sure the MTU fits */
2189 if ((p_cfg->mtu_present) && (p_cfg->mtu > L2CAP_MTU_SIZE)) {
2190 L2CAP_TRACE_WARNING("L2CAP - adjust MTU: %u too large", p_cfg->mtu);
2191 p_cfg->mtu = L2CAP_MTU_SIZE;
2192 }
2193 }
2194
2195 l2cu_process_our_cfg_req(p_ccb, &p_ccb->our_cfg);
2196 l2cu_send_peer_config_req(p_ccb, &p_ccb->our_cfg);
2197 alarm_set_on_mloop(p_ccb->l2c_ccb_timer, L2CAP_CHNL_CFG_TIMEOUT_MS,
2198 l2c_ccb_timer_timeout, p_ccb);
2199 return (true);
2200 }
2201 }
2202 }
2203
2204 /* Disconnect if the channels do not match */
2205 if (p_ccb->our_cfg.fcr.mode != peer_mode) {
2206 L2CAP_TRACE_WARNING("L2C CFG: Channels incompatible (local %d, peer %d)",
2207 p_ccb->our_cfg.fcr.mode, peer_mode);
2208 l2cu_disconnect_chnl(p_ccb);
2209 }
2210
2211 return (false);
2212 }
2213
2214 /*******************************************************************************
2215 *
2216 * Function l2c_fcr_process_peer_cfg_req
2217 *
2218 * Description This function is called to process the FCR options passed
2219 * in the peer's configuration request.
2220 *
2221 * Returns uint8_t - L2CAP_PEER_CFG_OK, L2CAP_PEER_CFG_UNACCEPTABLE,
2222 * or L2CAP_PEER_CFG_DISCONNECT.
2223 *
2224 ******************************************************************************/
l2c_fcr_process_peer_cfg_req(tL2C_CCB * p_ccb,tL2CAP_CFG_INFO * p_cfg)2225 uint8_t l2c_fcr_process_peer_cfg_req(tL2C_CCB* p_ccb, tL2CAP_CFG_INFO* p_cfg) {
2226 CHECK(p_ccb != NULL);
2227 CHECK(p_cfg != NULL);
2228
2229 uint16_t max_retrans_size;
2230 uint8_t fcr_ok = L2CAP_PEER_CFG_OK;
2231
2232 p_ccb->p_lcb->w4_info_rsp =
2233 false; /* Handles T61x SonyEricsson Bug in Info Request */
2234
2235 L2CAP_TRACE_EVENT(
2236 "l2c_fcr_process_peer_cfg_req() CFG fcr_present:%d fcr.mode:%d CCB FCR "
2237 "mode:%d preferred: %u allowed:%u",
2238 p_cfg->fcr_present, p_cfg->fcr.mode, p_ccb->our_cfg.fcr.mode,
2239 p_ccb->ertm_info.preferred_mode, p_ccb->ertm_info.allowed_modes);
2240
2241 /* If Peer wants basic, we are done (accept it or disconnect) */
2242 if (p_cfg->fcr.mode == L2CAP_FCR_BASIC_MODE) {
2243 /* If we do not allow basic, disconnect */
2244 if (!(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_BASIC))
2245 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2246 }
2247
2248 /* Need to negotiate if our modes are not the same */
2249 else if (p_cfg->fcr.mode != p_ccb->ertm_info.preferred_mode) {
2250 /* If peer wants a mode that we don't support then retry our mode (ex.
2251 *rtx/flc), OR
2252 ** If we want ERTM and they wanted streaming retry our mode.
2253 ** Note: If we have already determined they support our mode previously
2254 ** from their EXF mask.
2255 */
2256 if ((((1 << p_cfg->fcr.mode) & L2CAP_FCR_CHAN_OPT_ALL_MASK) == 0) ||
2257 (p_ccb->ertm_info.preferred_mode == L2CAP_FCR_ERTM_MODE)) {
2258 p_cfg->fcr.mode = p_ccb->our_cfg.fcr.mode;
2259 p_cfg->fcr.tx_win_sz = p_ccb->our_cfg.fcr.tx_win_sz;
2260 p_cfg->fcr.max_transmit = p_ccb->our_cfg.fcr.max_transmit;
2261 fcr_ok = L2CAP_PEER_CFG_UNACCEPTABLE;
2262 }
2263
2264 /* If we wanted basic, then try to renegotiate it */
2265 else if (p_ccb->ertm_info.preferred_mode == L2CAP_FCR_BASIC_MODE) {
2266 p_cfg->fcr.mode = L2CAP_FCR_BASIC_MODE;
2267 p_cfg->fcr.max_transmit = p_cfg->fcr.tx_win_sz = 0;
2268 p_cfg->fcr.rtrans_tout = p_cfg->fcr.mon_tout = p_cfg->fcr.mps = 0;
2269 p_ccb->our_cfg.fcr.rtrans_tout = p_ccb->our_cfg.fcr.mon_tout =
2270 p_ccb->our_cfg.fcr.mps = 0;
2271 fcr_ok = L2CAP_PEER_CFG_UNACCEPTABLE;
2272 }
2273
2274 /* Only other valid case is if they want ERTM and we wanted STM which should
2275 be
2276 accepted if we support it; otherwise the channel should be disconnected
2277 */
2278 else if ((p_cfg->fcr.mode != L2CAP_FCR_ERTM_MODE) ||
2279 !(p_ccb->ertm_info.allowed_modes & L2CAP_FCR_CHAN_OPT_ERTM)) {
2280 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2281 }
2282 }
2283
2284 /* Configuration for FCR channels so make any adjustments and fwd to upper
2285 * layer */
2286 if (fcr_ok == L2CAP_PEER_CFG_OK) {
2287 /* by default don't need to send params in the response */
2288 p_ccb->out_cfg_fcr_present = false;
2289
2290 /* Make any needed adjustments for the response to the peer */
2291 if (p_cfg->fcr_present && p_cfg->fcr.mode != L2CAP_FCR_BASIC_MODE) {
2292 /* Peer desires to bypass FCS check, and streaming or ERTM mode */
2293 if (p_cfg->fcs_present) {
2294 p_ccb->peer_cfg.fcs = p_cfg->fcs;
2295 p_ccb->peer_cfg_bits |= L2CAP_CH_CFG_MASK_FCS;
2296 if (p_cfg->fcs == L2CAP_CFG_FCS_BYPASS)
2297 p_ccb->bypass_fcs |= L2CAP_CFG_FCS_PEER;
2298 }
2299
2300 max_retrans_size = p_ccb->ertm_info.fcr_tx_buf_size - sizeof(BT_HDR) -
2301 L2CAP_MIN_OFFSET - L2CAP_SDU_LEN_OFFSET -
2302 L2CAP_FCS_LEN;
2303
2304 /* Ensure the MPS is not bigger than the MTU */
2305 if ((p_cfg->fcr.mps == 0) || (p_cfg->fcr.mps > p_ccb->peer_cfg.mtu)) {
2306 p_cfg->fcr.mps = p_ccb->peer_cfg.mtu;
2307 p_ccb->out_cfg_fcr_present = true;
2308 }
2309
2310 /* Ensure the MPS is not bigger than our retransmission buffer */
2311 if (p_cfg->fcr.mps > max_retrans_size) {
2312 L2CAP_TRACE_DEBUG("CFG: Overriding MPS to %d (orig %d)",
2313 max_retrans_size, p_cfg->fcr.mps);
2314
2315 p_cfg->fcr.mps = max_retrans_size;
2316 p_ccb->out_cfg_fcr_present = true;
2317 }
2318
2319 if (p_cfg->fcr.mode == L2CAP_FCR_ERTM_MODE ||
2320 p_cfg->fcr.mode == L2CAP_FCR_STREAM_MODE) {
2321 /* Always respond with FCR ERTM parameters */
2322 p_ccb->out_cfg_fcr_present = true;
2323 }
2324 }
2325
2326 /* Everything ok, so save the peer's adjusted fcr options */
2327 p_ccb->peer_cfg.fcr = p_cfg->fcr;
2328
2329 if (p_cfg->fcr_present) p_ccb->peer_cfg_bits |= L2CAP_CH_CFG_MASK_FCR;
2330 } else if (fcr_ok == L2CAP_PEER_CFG_UNACCEPTABLE) {
2331 /* Allow peer only one retry for mode */
2332 if (p_ccb->peer_cfg_already_rejected)
2333 fcr_ok = L2CAP_PEER_CFG_DISCONNECT;
2334 else
2335 p_ccb->peer_cfg_already_rejected = true;
2336 }
2337
2338 return (fcr_ok);
2339 }
2340
2341 #if (L2CAP_ERTM_STATS == TRUE)
2342 /*******************************************************************************
2343 *
2344 * Function l2c_fcr_collect_ack_delay
2345 *
2346 * Description collect throughput, delay, queue size of waiting ack
2347 *
2348 * Parameters
2349 * tL2C_CCB
2350 *
2351 * Returns void
2352 *
2353 ******************************************************************************/
l2c_fcr_collect_ack_delay(tL2C_CCB * p_ccb,uint8_t num_bufs_acked)2354 static void l2c_fcr_collect_ack_delay(tL2C_CCB* p_ccb, uint8_t num_bufs_acked) {
2355 uint32_t index;
2356 BT_HDR* p_buf;
2357 uint8_t* p;
2358 uint32_t timestamp, delay;
2359 uint8_t xx;
2360 uint8_t str[120];
2361
2362 index = p_ccb->fcrb.ack_delay_avg_index;
2363
2364 /* update sum, max and min of waiting for ack queue size */
2365 p_ccb->fcrb.ack_q_count_avg[index] +=
2366 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q);
2367
2368 if (fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q) >
2369 p_ccb->fcrb.ack_q_count_max[index])
2370 p_ccb->fcrb.ack_q_count_max[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_min[index])
2375 p_ccb->fcrb.ack_q_count_min[index] =
2376 fixed_queue_length(p_ccb->fcrb.waiting_for_ack_q);
2377
2378 /* update sum, max and min of round trip delay of acking */
2379 list_t* list = NULL;
2380 if (!fixed_queue_is_empty(p_ccb->fcrb.waiting_for_ack_q))
2381 list = fixed_queue_get_list(p_ccb->fcrb.waiting_for_ack_q);
2382 if (list != NULL) {
2383 for (const list_node_t *node = list_begin(list), xx = 0;
2384 (node != list_end(list)) && (xx < num_bufs_acked);
2385 node = list_next(node), xx++) {
2386 p_buf = list_node(node);
2387 /* adding up length of acked I-frames to get throughput */
2388 p_ccb->fcrb.throughput[index] += p_buf->len - 8;
2389
2390 if (xx == num_bufs_acked - 1) {
2391 /* get timestamp from tx I-frame that receiver is acking */
2392 p = ((uint8_t*)(p_buf + 1)) + p_buf->offset + p_buf->len;
2393 if (p_ccb->bypass_fcs != L2CAP_BYPASS_FCS) {
2394 p += L2CAP_FCS_LEN;
2395 }
2396
2397 STREAM_TO_UINT32(timestamp, p);
2398 delay = time_get_os_boottime_ms() - timestamp;
2399
2400 p_ccb->fcrb.ack_delay_avg[index] += delay;
2401 if (delay > p_ccb->fcrb.ack_delay_max[index])
2402 p_ccb->fcrb.ack_delay_max[index] = delay;
2403 if (delay < p_ccb->fcrb.ack_delay_min[index])
2404 p_ccb->fcrb.ack_delay_min[index] = delay;
2405 }
2406 }
2407 }
2408
2409 p_ccb->fcrb.ack_delay_avg_count++;
2410
2411 /* calculate average and initialize next avg, min and max */
2412 if (p_ccb->fcrb.ack_delay_avg_count > L2CAP_ERTM_STATS_AVG_NUM_SAMPLES) {
2413 p_ccb->fcrb.ack_delay_avg_count = 0;
2414
2415 p_ccb->fcrb.ack_q_count_avg[index] /= L2CAP_ERTM_STATS_AVG_NUM_SAMPLES;
2416 p_ccb->fcrb.ack_delay_avg[index] /= L2CAP_ERTM_STATS_AVG_NUM_SAMPLES;
2417
2418 /* calculate throughput */
2419 timestamp = time_get_os_boottime_ms();
2420 if (timestamp - p_ccb->fcrb.throughput_start > 0)
2421 p_ccb->fcrb.throughput[index] /=
2422 (timestamp - p_ccb->fcrb.throughput_start);
2423
2424 p_ccb->fcrb.throughput_start = timestamp;
2425
2426 snprintf(
2427 str, sizeof(str),
2428 "[%02u] throughput: %5u, ack_delay avg:%3u, min:%3u, max:%3u, "
2429 "ack_q_count avg:%3u, min:%3u, max:%3u",
2430 index, p_ccb->fcrb.throughput[index], p_ccb->fcrb.ack_delay_avg[index],
2431 p_ccb->fcrb.ack_delay_min[index], p_ccb->fcrb.ack_delay_max[index],
2432 p_ccb->fcrb.ack_q_count_avg[index], p_ccb->fcrb.ack_q_count_min[index],
2433 p_ccb->fcrb.ack_q_count_max[index]);
2434
2435 BT_TRACE(TRACE_CTRL_GENERAL | TRACE_LAYER_GKI | TRACE_ORG_GKI,
2436 TRACE_TYPE_GENERIC, "%s", str);
2437
2438 index = (index + 1) % L2CAP_ERTM_STATS_NUM_AVG;
2439 p_ccb->fcrb.ack_delay_avg_index = index;
2440
2441 p_ccb->fcrb.ack_q_count_max[index] = 0;
2442 p_ccb->fcrb.ack_q_count_min[index] = 0xFFFFFFFF;
2443 p_ccb->fcrb.ack_q_count_avg[index] = 0;
2444
2445 p_ccb->fcrb.ack_delay_max[index] = 0;
2446 p_ccb->fcrb.ack_delay_min[index] = 0xFFFFFFFF;
2447 p_ccb->fcrb.ack_delay_avg[index] = 0;
2448
2449 p_ccb->fcrb.throughput[index] = 0;
2450 }
2451 }
2452 #endif
2453