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00008 #include <linux/netdevice.h>
00009 #include <linux/types.h>
00010 #include <linux/skbuff.h>
00011 #include <linux/debugfs.h>
00012 #include <linux/random.h>
00013 #include <linux/ieee80211.h>
00014 #include <net/mac80211.h>
00015 #include "rate.h"
00016 #include "rc80211_minstrel.h"
00017 #include "rc80211_minstrel_ht.h"
00018
00019 #define AVG_PKT_SIZE 1200
00020 #define SAMPLE_COLUMNS 10
00021 #define EWMA_LEVEL 75
00022
00023
00024 #define MCS_NBITS (AVG_PKT_SIZE << 3)
00025
00026
00027 #define MCS_NSYMS(bps) ((MCS_NBITS + (bps) - 1) / (bps))
00028
00029
00030 #define MCS_SYMBOL_TIME(sgi, syms) \
00031 (sgi ? \
00032 ((syms) * 18 + 4) / 5 : \
00033 (syms) << 2 \
00034 )
00035
00036
00037 #define MCS_DURATION(streams, sgi, bps) MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps)))
00038
00039
00040
00041
00042 #define GROUP_IDX(_streams, _sgi, _ht40) \
00043 MINSTREL_MAX_STREAMS * 2 * _ht40 + \
00044 MINSTREL_MAX_STREAMS * _sgi + \
00045 _streams - 1
00046
00047
00048 #define MCS_GROUP(_streams, _sgi, _ht40) \
00049 [GROUP_IDX(_streams, _sgi, _ht40)] = { \
00050 .streams = _streams, \
00051 .flags = \
00052 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
00053 (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
00054 .duration = { \
00055 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \
00056 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \
00057 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \
00058 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \
00059 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \
00060 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \
00061 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \
00062 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \
00063 } \
00064 }
00065
00066
00067
00068
00069
00070
00071
00072
00073
00074 const struct mcs_group minstrel_mcs_groups[] = {
00075 MCS_GROUP(1, 0, 0),
00076 MCS_GROUP(2, 0, 0),
00077 #if MINSTREL_MAX_STREAMS >= 3
00078 MCS_GROUP(3, 0, 0),
00079 #endif
00080
00081 MCS_GROUP(1, 1, 0),
00082 MCS_GROUP(2, 1, 0),
00083 #if MINSTREL_MAX_STREAMS >= 3
00084 MCS_GROUP(3, 1, 0),
00085 #endif
00086
00087 MCS_GROUP(1, 0, 1),
00088 MCS_GROUP(2, 0, 1),
00089 #if MINSTREL_MAX_STREAMS >= 3
00090 MCS_GROUP(3, 0, 1),
00091 #endif
00092
00093 MCS_GROUP(1, 1, 1),
00094 MCS_GROUP(2, 1, 1),
00095 #if MINSTREL_MAX_STREAMS >= 3
00096 MCS_GROUP(3, 1, 1),
00097 #endif
00098 };
00099
00100 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES];
00101
00102
00103
00104
00105 static int
00106 minstrel_ewma(int old, int new, int weight)
00107 {
00108 return (new * (100 - weight) + old * weight) / 100;
00109 }
00110
00111
00112
00113
00114 static int
00115 minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate)
00116 {
00117 return GROUP_IDX((rate->idx / MCS_GROUP_RATES) + 1,
00118 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
00119 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH));
00120 }
00121
00122 static inline struct minstrel_rate_stats *
00123 minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
00124 {
00125 return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
00126 }
00127
00128
00129
00130
00131
00132 static void
00133 minstrel_calc_rate_ewma(struct minstrel_rate_stats *mr)
00134 {
00135 if (unlikely(mr->attempts > 0)) {
00136 mr->sample_skipped = 0;
00137 mr->cur_prob = MINSTREL_FRAC(mr->success, mr->attempts);
00138 if (!mr->att_hist)
00139 mr->probability = mr->cur_prob;
00140 else
00141 mr->probability = minstrel_ewma(mr->probability,
00142 mr->cur_prob, EWMA_LEVEL);
00143 mr->att_hist += mr->attempts;
00144 mr->succ_hist += mr->success;
00145 } else {
00146 mr->sample_skipped++;
00147 }
00148 mr->last_success = mr->success;
00149 mr->last_attempts = mr->attempts;
00150 mr->success = 0;
00151 mr->attempts = 0;
00152 }
00153
00154
00155
00156
00157
00158 static void
00159 minstrel_ht_calc_tp(struct minstrel_ht_sta *mi, int group, int rate)
00160 {
00161 struct minstrel_rate_stats *mr;
00162 unsigned int usecs;
00163
00164 mr = &mi->groups[group].rates[rate];
00165
00166 if (mr->probability < MINSTREL_FRAC(1, 10)) {
00167 mr->cur_tp = 0;
00168 return;
00169 }
00170
00171 usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
00172 usecs += minstrel_mcs_groups[group].duration[rate];
00173 mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability);
00174 }
00175
00176
00177
00178
00179
00180
00181
00182
00183
00184
00185 static void
00186 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
00187 {
00188 struct minstrel_mcs_group_data *mg;
00189 struct minstrel_rate_stats *mr;
00190 int cur_prob, cur_prob_tp, cur_tp, cur_tp2;
00191 int group, i, index;
00192
00193 if (mi->ampdu_packets > 0) {
00194 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
00195 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
00196 mi->ampdu_len = 0;
00197 mi->ampdu_packets = 0;
00198 }
00199
00200 mi->sample_slow = 0;
00201 mi->sample_count = 0;
00202 mi->max_tp_rate = 0;
00203 mi->max_tp_rate2 = 0;
00204 mi->max_prob_rate = 0;
00205
00206 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
00207 cur_prob = 0;
00208 cur_prob_tp = 0;
00209 cur_tp = 0;
00210 cur_tp2 = 0;
00211
00212 mg = &mi->groups[group];
00213 if (!mg->supported)
00214 continue;
00215
00216 mg->max_tp_rate = 0;
00217 mg->max_tp_rate2 = 0;
00218 mg->max_prob_rate = 0;
00219 mi->sample_count++;
00220
00221 for (i = 0; i < MCS_GROUP_RATES; i++) {
00222 if (!(mg->supported & BIT(i)))
00223 continue;
00224
00225 mr = &mg->rates[i];
00226 mr->retry_updated = false;
00227 index = MCS_GROUP_RATES * group + i;
00228 minstrel_calc_rate_ewma(mr);
00229 minstrel_ht_calc_tp(mi, group, i);
00230
00231 if (!mr->cur_tp)
00232 continue;
00233
00234
00235 if (!i && minstrel_mcs_groups[group].streams == 1)
00236 continue;
00237
00238 if ((mr->cur_tp > cur_prob_tp && mr->probability >
00239 MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) {
00240 mg->max_prob_rate = index;
00241 cur_prob = mr->probability;
00242 cur_prob_tp = mr->cur_tp;
00243 }
00244
00245 if (mr->cur_tp > cur_tp) {
00246 swap(index, mg->max_tp_rate);
00247 cur_tp = mr->cur_tp;
00248 mr = minstrel_get_ratestats(mi, index);
00249 }
00250
00251 if (index >= mg->max_tp_rate)
00252 continue;
00253
00254 if (mr->cur_tp > cur_tp2) {
00255 mg->max_tp_rate2 = index;
00256 cur_tp2 = mr->cur_tp;
00257 }
00258 }
00259 }
00260
00261
00262 mi->sample_count *= 4;
00263
00264 cur_prob = 0;
00265 cur_prob_tp = 0;
00266 cur_tp = 0;
00267 cur_tp2 = 0;
00268 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
00269 mg = &mi->groups[group];
00270 if (!mg->supported)
00271 continue;
00272
00273 mr = minstrel_get_ratestats(mi, mg->max_prob_rate);
00274 if (cur_prob_tp < mr->cur_tp &&
00275 minstrel_mcs_groups[group].streams == 1) {
00276 mi->max_prob_rate = mg->max_prob_rate;
00277 cur_prob = mr->cur_prob;
00278 cur_prob_tp = mr->cur_tp;
00279 }
00280
00281 mr = minstrel_get_ratestats(mi, mg->max_tp_rate);
00282 if (cur_tp < mr->cur_tp) {
00283 mi->max_tp_rate2 = mi->max_tp_rate;
00284 cur_tp2 = cur_tp;
00285 mi->max_tp_rate = mg->max_tp_rate;
00286 cur_tp = mr->cur_tp;
00287 }
00288
00289 mr = minstrel_get_ratestats(mi, mg->max_tp_rate2);
00290 if (cur_tp2 < mr->cur_tp) {
00291 mi->max_tp_rate2 = mg->max_tp_rate2;
00292 cur_tp2 = mr->cur_tp;
00293 }
00294 }
00295
00296 mi->stats_update = jiffies;
00297 }
00298
00299 static bool
00300 minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate)
00301 {
00302 if (rate->idx < 0)
00303 return false;
00304
00305 if (!rate->count)
00306 return false;
00307
00308 return !!(rate->flags & IEEE80211_TX_RC_MCS);
00309 }
00310
00311 static void
00312 minstrel_next_sample_idx(struct minstrel_ht_sta *mi)
00313 {
00314 struct minstrel_mcs_group_data *mg;
00315
00316 for (;;) {
00317 mi->sample_group++;
00318 mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
00319 mg = &mi->groups[mi->sample_group];
00320
00321 if (!mg->supported)
00322 continue;
00323
00324 if (++mg->index >= MCS_GROUP_RATES) {
00325 mg->index = 0;
00326 if (++mg->column >= ARRAY_SIZE(sample_table))
00327 mg->column = 0;
00328 }
00329 break;
00330 }
00331 }
00332
00333 static void
00334 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx,
00335 bool primary)
00336 {
00337 int group, orig_group;
00338
00339 orig_group = group = *idx / MCS_GROUP_RATES;
00340 while (group > 0) {
00341 group--;
00342
00343 if (!mi->groups[group].supported)
00344 continue;
00345
00346 if (minstrel_mcs_groups[group].streams >
00347 minstrel_mcs_groups[orig_group].streams)
00348 continue;
00349
00350 if (primary)
00351 *idx = mi->groups[group].max_tp_rate;
00352 else
00353 *idx = mi->groups[group].max_tp_rate2;
00354 break;
00355 }
00356 }
00357
00358 static void
00359 minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb)
00360 {
00361 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
00362 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
00363 u16 tid;
00364
00365 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control)))
00366 return;
00367
00368 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE)))
00369 return;
00370
00371 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
00372 if (likely(sta->ampdu_mlme.tid_tx[tid]))
00373 return;
00374
00375 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
00376 return;
00377
00378 ieee80211_start_tx_ba_session(pubsta, tid, 5000);
00379 }
00380
00381 static void
00382 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
00383 struct ieee80211_sta *sta, void *priv_sta,
00384 struct sk_buff *skb)
00385 {
00386 struct minstrel_ht_sta_priv *msp = priv_sta;
00387 struct minstrel_ht_sta *mi = &msp->ht;
00388 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
00389 struct ieee80211_tx_rate *ar = info->status.rates;
00390 struct minstrel_rate_stats *rate, *rate2;
00391 struct minstrel_priv *mp = priv;
00392 bool last = false;
00393 int group;
00394 int i = 0;
00395
00396 if (!msp->is_ht)
00397 return mac80211_minstrel.tx_status(priv, sband, sta, &msp->legacy, skb);
00398
00399
00400 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
00401 !(info->flags & IEEE80211_TX_STAT_AMPDU))
00402 return;
00403
00404 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) {
00405 info->status.ampdu_ack_len =
00406 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0);
00407 info->status.ampdu_len = 1;
00408 }
00409
00410 mi->ampdu_packets++;
00411 mi->ampdu_len += info->status.ampdu_len;
00412
00413 if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
00414 mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
00415 mi->sample_tries = 2;
00416 mi->sample_count--;
00417 }
00418
00419 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
00420 mi->sample_packets += info->status.ampdu_len;
00421
00422 for (i = 0; !last; i++) {
00423 last = (i == IEEE80211_TX_MAX_RATES - 1) ||
00424 !minstrel_ht_txstat_valid(&ar[i + 1]);
00425
00426 if (!minstrel_ht_txstat_valid(&ar[i]))
00427 break;
00428
00429 group = minstrel_ht_get_group_idx(&ar[i]);
00430 rate = &mi->groups[group].rates[ar[i].idx % 8];
00431
00432 if (last)
00433 rate->success += info->status.ampdu_ack_len;
00434
00435 rate->attempts += ar[i].count * info->status.ampdu_len;
00436 }
00437
00438
00439
00440
00441
00442 rate = minstrel_get_ratestats(mi, mi->max_tp_rate);
00443 if (rate->attempts > 30 &&
00444 MINSTREL_FRAC(rate->success, rate->attempts) <
00445 MINSTREL_FRAC(20, 100))
00446 minstrel_downgrade_rate(mi, &mi->max_tp_rate, true);
00447
00448 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2);
00449 if (rate2->attempts > 30 &&
00450 MINSTREL_FRAC(rate2->success, rate2->attempts) <
00451 MINSTREL_FRAC(20, 100))
00452 minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false);
00453
00454 if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) {
00455 minstrel_ht_update_stats(mp, mi);
00456 if (!(info->flags & IEEE80211_TX_CTL_AMPDU))
00457 minstrel_aggr_check(sta, skb);
00458 }
00459 }
00460
00461 static void
00462 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
00463 int index)
00464 {
00465 struct minstrel_rate_stats *mr;
00466 const struct mcs_group *group;
00467 unsigned int tx_time, tx_time_rtscts, tx_time_data;
00468 unsigned int cw = mp->cw_min;
00469 unsigned int ctime = 0;
00470 unsigned int t_slot = 9;
00471 unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
00472
00473 mr = minstrel_get_ratestats(mi, index);
00474 if (mr->probability < MINSTREL_FRAC(1, 10)) {
00475 mr->retry_count = 1;
00476 mr->retry_count_rtscts = 1;
00477 return;
00478 }
00479
00480 mr->retry_count = 2;
00481 mr->retry_count_rtscts = 2;
00482 mr->retry_updated = true;
00483
00484 group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00485 tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len;
00486
00487
00488 ctime = (t_slot * cw) >> 1;
00489 cw = min((cw << 1) | 1, mp->cw_max);
00490 ctime += (t_slot * cw) >> 1;
00491 cw = min((cw << 1) | 1, mp->cw_max);
00492
00493
00494 tx_time = ctime + 2 * (mi->overhead + tx_time_data);
00495 tx_time_rtscts = ctime + 2 * (mi->overhead_rtscts + tx_time_data);
00496
00497
00498 do {
00499
00500 ctime = (t_slot * cw) >> 1;
00501 cw = min((cw << 1) | 1, mp->cw_max);
00502
00503
00504 tx_time += ctime + mi->overhead + tx_time_data;
00505 tx_time_rtscts += ctime + mi->overhead_rtscts + tx_time_data;
00506
00507 if (tx_time_rtscts < mp->segment_size)
00508 mr->retry_count_rtscts++;
00509 } while ((tx_time < mp->segment_size) &&
00510 (++mr->retry_count < mp->max_retry));
00511 }
00512
00513
00514 static void
00515 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
00516 struct ieee80211_tx_rate *rate, int index,
00517 bool sample, bool rtscts)
00518 {
00519 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00520 struct minstrel_rate_stats *mr;
00521
00522 mr = minstrel_get_ratestats(mi, index);
00523 if (!mr->retry_updated)
00524 minstrel_calc_retransmit(mp, mi, index);
00525
00526 if (sample)
00527 rate->count = 1;
00528 else if (mr->probability < MINSTREL_FRAC(20, 100))
00529 rate->count = 2;
00530 else if (rtscts)
00531 rate->count = mr->retry_count_rtscts;
00532 else
00533 rate->count = mr->retry_count;
00534
00535 rate->flags = IEEE80211_TX_RC_MCS | group->flags;
00536 if (rtscts)
00537 rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;
00538 rate->idx = index % MCS_GROUP_RATES + (group->streams - 1) * MCS_GROUP_RATES;
00539 }
00540
00541 static inline int
00542 minstrel_get_duration(int index)
00543 {
00544 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00545 return group->duration[index % MCS_GROUP_RATES];
00546 }
00547
00548 static int
00549 minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
00550 {
00551 struct minstrel_rate_stats *mr;
00552 struct minstrel_mcs_group_data *mg;
00553 int sample_idx = 0;
00554
00555 if (mi->sample_wait > 0) {
00556 mi->sample_wait--;
00557 return -1;
00558 }
00559
00560 if (!mi->sample_tries)
00561 return -1;
00562
00563 mi->sample_tries--;
00564 mg = &mi->groups[mi->sample_group];
00565 sample_idx = sample_table[mg->column][mg->index];
00566 mr = &mg->rates[sample_idx];
00567 sample_idx += mi->sample_group * MCS_GROUP_RATES;
00568 minstrel_next_sample_idx(mi);
00569
00570
00571
00572
00573
00574
00575 if (sample_idx == mi->max_tp_rate)
00576 return -1;
00577
00578
00579
00580
00581 if (!mp->has_mrr && (mr->probability > MINSTREL_FRAC(95, 100)))
00582 return -1;
00583
00584
00585
00586
00587
00588 if (minstrel_get_duration(sample_idx) >
00589 minstrel_get_duration(mi->max_tp_rate)) {
00590 if (mr->sample_skipped < 20)
00591 return -1;
00592
00593 if (mi->sample_slow++ > 2)
00594 return -1;
00595 }
00596
00597 return sample_idx;
00598 }
00599
00600 static void
00601 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
00602 struct ieee80211_tx_rate_control *txrc)
00603 {
00604 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
00605 struct ieee80211_tx_rate *ar = info->status.rates;
00606 struct minstrel_ht_sta_priv *msp = priv_sta;
00607 struct minstrel_ht_sta *mi = &msp->ht;
00608 struct minstrel_priv *mp = priv;
00609 int sample_idx;
00610 bool sample = false;
00611
00612 if (rate_control_send_low(sta, priv_sta, txrc))
00613 return;
00614
00615 if (!msp->is_ht)
00616 return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc);
00617
00618 info->flags |= mi->tx_flags;
00619
00620
00621 if (mp->hw->max_rates == 1 &&
00622 txrc->skb->protocol == cpu_to_be16(ETH_P_PAE))
00623 sample_idx = -1;
00624 else
00625 sample_idx = minstrel_get_sample_rate(mp, mi);
00626
00627 #ifdef CONFIG_MAC80211_DEBUGFS
00628
00629 if (mp->fixed_rate_idx != -1)
00630 sample_idx = mp->fixed_rate_idx;
00631 #endif
00632
00633 if (sample_idx >= 0) {
00634 sample = true;
00635 minstrel_ht_set_rate(mp, mi, &ar[0], sample_idx,
00636 true, false);
00637 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
00638 } else {
00639 minstrel_ht_set_rate(mp, mi, &ar[0], mi->max_tp_rate,
00640 false, false);
00641 }
00642
00643 if (mp->hw->max_rates >= 3) {
00644
00645
00646
00647
00648
00649 if (sample_idx >= 0)
00650 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate,
00651 false, false);
00652 else
00653 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate2,
00654 false, true);
00655
00656 minstrel_ht_set_rate(mp, mi, &ar[2], mi->max_prob_rate,
00657 false, !sample);
00658
00659 ar[3].count = 0;
00660 ar[3].idx = -1;
00661 } else if (mp->hw->max_rates == 2) {
00662
00663
00664
00665
00666
00667 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_prob_rate,
00668 false, !sample);
00669
00670 ar[2].count = 0;
00671 ar[2].idx = -1;
00672 } else {
00673
00674 ar[1].count = 0;
00675 ar[1].idx = -1;
00676 }
00677
00678 mi->total_packets++;
00679
00680
00681 if (mi->total_packets == ~0) {
00682 mi->total_packets = 0;
00683 mi->sample_packets = 0;
00684 }
00685 }
00686
00687 static void
00688 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
00689 struct ieee80211_sta *sta, void *priv_sta)
00690 {
00691 struct minstrel_priv *mp = priv;
00692 struct minstrel_ht_sta_priv *msp = priv_sta;
00693 struct minstrel_ht_sta *mi = &msp->ht;
00694 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
00695 u16 sta_cap = sta->ht_cap.cap;
00696 int n_supported = 0;
00697 int ack_dur;
00698 int stbc;
00699 int i;
00700 unsigned int smps;
00701
00702
00703 if (!sta->ht_cap.ht_supported)
00704 goto use_legacy;
00705
00706 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) !=
00707 MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS);
00708
00709 msp->is_ht = true;
00710 memset(mi, 0, sizeof(*mi));
00711 mi->stats_update = jiffies;
00712
00713 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1);
00714 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1) + ack_dur;
00715 mi->overhead_rtscts = mi->overhead + 2 * ack_dur;
00716
00717 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1);
00718
00719
00720 if (mp->has_mrr) {
00721 mi->sample_count = 16;
00722 mi->sample_wait = 0;
00723 } else {
00724 mi->sample_count = 8;
00725 mi->sample_wait = 8;
00726 }
00727 mi->sample_tries = 4;
00728
00729 stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
00730 IEEE80211_HT_CAP_RX_STBC_SHIFT;
00731 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
00732
00733 if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
00734 mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
00735
00736 smps = (sta_cap & IEEE80211_HT_CAP_SM_PS) >>
00737 IEEE80211_HT_CAP_SM_PS_SHIFT;
00738
00739 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
00740 u16 req = 0;
00741
00742 mi->groups[i].supported = 0;
00743 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_SHORT_GI) {
00744 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
00745 req |= IEEE80211_HT_CAP_SGI_40;
00746 else
00747 req |= IEEE80211_HT_CAP_SGI_20;
00748 }
00749
00750 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
00751 req |= IEEE80211_HT_CAP_SUP_WIDTH_20_40;
00752
00753 if ((sta_cap & req) != req)
00754 continue;
00755
00756
00757 if (smps == WLAN_HT_CAP_SM_PS_STATIC &&
00758 minstrel_mcs_groups[i].streams > 1)
00759 continue;
00760
00761 mi->groups[i].supported =
00762 mcs->rx_mask[minstrel_mcs_groups[i].streams - 1];
00763
00764 if (mi->groups[i].supported)
00765 n_supported++;
00766 }
00767
00768 if (!n_supported)
00769 goto use_legacy;
00770
00771 return;
00772
00773 use_legacy:
00774 msp->is_ht = false;
00775 memset(&msp->legacy, 0, sizeof(msp->legacy));
00776 msp->legacy.r = msp->ratelist;
00777 msp->legacy.sample_table = msp->sample_table;
00778 return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy);
00779 }
00780
00781 static void
00782 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband,
00783 struct ieee80211_sta *sta, void *priv_sta)
00784 {
00785 minstrel_ht_update_caps(priv, sband, sta, priv_sta);
00786 }
00787
00788 static void
00789 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband,
00790 struct ieee80211_sta *sta, void *priv_sta,
00791 u32 changed)
00792 {
00793 minstrel_ht_update_caps(priv, sband, sta, priv_sta);
00794 }
00795
00796 static void *
00797 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
00798 {
00799 struct ieee80211_supported_band *sband;
00800 struct minstrel_ht_sta_priv *msp;
00801 struct minstrel_priv *mp = priv;
00802 struct ieee80211_hw *hw = mp->hw;
00803 int max_rates = 0;
00804 int i;
00805
00806 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
00807 sband = hw->wiphy->bands[i];
00808 if (sband && sband->n_bitrates > max_rates)
00809 max_rates = sband->n_bitrates;
00810 }
00811
00812 msp = kzalloc(sizeof(*msp), gfp);
00813 if (!msp)
00814 return NULL;
00815
00816 msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
00817 if (!msp->ratelist)
00818 goto error;
00819
00820 msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
00821 if (!msp->sample_table)
00822 goto error1;
00823
00824 return msp;
00825
00826 error1:
00827 kfree(msp->ratelist);
00828 error:
00829 kfree(msp);
00830 return NULL;
00831 }
00832
00833 static void
00834 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
00835 {
00836 struct minstrel_ht_sta_priv *msp = priv_sta;
00837
00838 kfree(msp->sample_table);
00839 kfree(msp->ratelist);
00840 kfree(msp);
00841 }
00842
00843 static void *
00844 minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
00845 {
00846 return mac80211_minstrel.alloc(hw, debugfsdir);
00847 }
00848
00849 static void
00850 minstrel_ht_free(void *priv)
00851 {
00852 mac80211_minstrel.free(priv);
00853 }
00854
00855 static struct rate_control_ops mac80211_minstrel_ht = {
00856 .name = "minstrel_ht",
00857 .tx_status = minstrel_ht_tx_status,
00858 .get_rate = minstrel_ht_get_rate,
00859 .rate_init = minstrel_ht_rate_init,
00860 .rate_update = minstrel_ht_rate_update,
00861 .alloc_sta = minstrel_ht_alloc_sta,
00862 .free_sta = minstrel_ht_free_sta,
00863 .alloc = minstrel_ht_alloc,
00864 .free = minstrel_ht_free,
00865 #ifdef CONFIG_MAC80211_DEBUGFS
00866 .add_sta_debugfs = minstrel_ht_add_sta_debugfs,
00867 .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
00868 #endif
00869 };
00870
00871
00872 static void
00873 init_sample_table(void)
00874 {
00875 int col, i, new_idx;
00876 u8 rnd[MCS_GROUP_RATES];
00877
00878 memset(sample_table, 0xff, sizeof(sample_table));
00879 for (col = 0; col < SAMPLE_COLUMNS; col++) {
00880 for (i = 0; i < MCS_GROUP_RATES; i++) {
00881 get_random_bytes(rnd, sizeof(rnd));
00882 new_idx = (i + rnd[i]) % MCS_GROUP_RATES;
00883
00884 while (sample_table[col][new_idx] != 0xff)
00885 new_idx = (new_idx + 1) % MCS_GROUP_RATES;
00886
00887 sample_table[col][new_idx] = i;
00888 }
00889 }
00890 }
00891
00892 int __init
00893 rc80211_minstrel_ht_init(void)
00894 {
00895 init_sample_table();
00896 return ieee80211_rate_control_register(&mac80211_minstrel_ht);
00897 }
00898
00899 void
00900 rc80211_minstrel_ht_exit(void)
00901 {
00902 ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
00903 }