00001
00002
00003
00004
00005
00006
00007
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 #define MCS_GROUP(_streams, _sgi, _ht40) { \
00041 .streams = _streams, \
00042 .flags = \
00043 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
00044 (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
00045 .duration = { \
00046 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \
00047 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \
00048 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \
00049 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \
00050 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \
00051 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \
00052 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \
00053 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \
00054 } \
00055 }
00056
00057
00058
00059
00060
00061
00062 const struct mcs_group minstrel_mcs_groups[] = {
00063 MCS_GROUP(1, 0, 0),
00064 MCS_GROUP(2, 0, 0),
00065 #if MINSTREL_MAX_STREAMS >= 3
00066 MCS_GROUP(3, 0, 0),
00067 #endif
00068
00069 MCS_GROUP(1, 1, 0),
00070 MCS_GROUP(2, 1, 0),
00071 #if MINSTREL_MAX_STREAMS >= 3
00072 MCS_GROUP(3, 1, 0),
00073 #endif
00074
00075 MCS_GROUP(1, 0, 1),
00076 MCS_GROUP(2, 0, 1),
00077 #if MINSTREL_MAX_STREAMS >= 3
00078 MCS_GROUP(3, 0, 1),
00079 #endif
00080
00081 MCS_GROUP(1, 1, 1),
00082 MCS_GROUP(2, 1, 1),
00083 #if MINSTREL_MAX_STREAMS >= 3
00084 MCS_GROUP(3, 1, 1),
00085 #endif
00086 };
00087
00088 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES];
00089
00090
00091
00092
00093 static int
00094 minstrel_ewma(int old, int new, int weight)
00095 {
00096 return (new * (100 - weight) + old * weight) / 100;
00097 }
00098
00099
00100
00101
00102 static int
00103 minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate)
00104 {
00105 int streams = (rate->idx / MCS_GROUP_RATES) + 1;
00106 u32 flags = IEEE80211_TX_RC_SHORT_GI | IEEE80211_TX_RC_40_MHZ_WIDTH;
00107 int i;
00108
00109 for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) {
00110 if (minstrel_mcs_groups[i].streams != streams)
00111 continue;
00112 if (minstrel_mcs_groups[i].flags != (rate->flags & flags))
00113 continue;
00114
00115 return i;
00116 }
00117
00118 WARN_ON(1);
00119 return 0;
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_priv *mp, 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_priv *mp, struct minstrel_ht_sta *mi,
00160 int group, int rate)
00161 {
00162 struct minstrel_rate_stats *mr;
00163 unsigned int usecs;
00164
00165 mr = &mi->groups[group].rates[rate];
00166
00167 if (mr->probability < MINSTREL_FRAC(1, 10)) {
00168 mr->cur_tp = 0;
00169 return;
00170 }
00171
00172 usecs = mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
00173 usecs += minstrel_mcs_groups[group].duration[rate];
00174 mr->cur_tp = MINSTREL_TRUNC((1000000 / usecs) * mr->probability);
00175 }
00176
00177
00178
00179
00180
00181
00182
00183
00184
00185
00186 static void
00187 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
00188 {
00189 struct minstrel_mcs_group_data *mg;
00190 struct minstrel_rate_stats *mr;
00191 int cur_prob, cur_prob_tp, cur_tp, cur_tp2;
00192 int group, i, index;
00193
00194 if (mi->ampdu_packets > 0) {
00195 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
00196 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
00197 mi->ampdu_len = 0;
00198 mi->ampdu_packets = 0;
00199 }
00200
00201 mi->sample_slow = 0;
00202 mi->sample_count = 0;
00203 mi->max_tp_rate = 0;
00204 mi->max_tp_rate2 = 0;
00205 mi->max_prob_rate = 0;
00206
00207 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
00208 cur_prob = 0;
00209 cur_prob_tp = 0;
00210 cur_tp = 0;
00211 cur_tp2 = 0;
00212
00213 mg = &mi->groups[group];
00214 if (!mg->supported)
00215 continue;
00216
00217 mg->max_tp_rate = 0;
00218 mg->max_tp_rate2 = 0;
00219 mg->max_prob_rate = 0;
00220 mi->sample_count++;
00221
00222 for (i = 0; i < MCS_GROUP_RATES; i++) {
00223 if (!(mg->supported & BIT(i)))
00224 continue;
00225
00226 mr = &mg->rates[i];
00227 mr->retry_updated = false;
00228 index = MCS_GROUP_RATES * group + i;
00229 minstrel_calc_rate_ewma(mp, mr);
00230 minstrel_ht_calc_tp(mp, mi, group, i);
00231
00232 if (!mr->cur_tp)
00233 continue;
00234
00235
00236 if (!i && minstrel_mcs_groups[group].streams == 1)
00237 continue;
00238
00239 if ((mr->cur_tp > cur_prob_tp && mr->probability >
00240 MINSTREL_FRAC(3, 4)) || mr->probability > cur_prob) {
00241 mg->max_prob_rate = index;
00242 cur_prob = mr->probability;
00243 cur_prob_tp = mr->cur_tp;
00244 }
00245
00246 if (mr->cur_tp > cur_tp) {
00247 swap(index, mg->max_tp_rate);
00248 cur_tp = mr->cur_tp;
00249 mr = minstrel_get_ratestats(mi, index);
00250 }
00251
00252 if (index >= mg->max_tp_rate)
00253 continue;
00254
00255 if (mr->cur_tp > cur_tp2) {
00256 mg->max_tp_rate2 = index;
00257 cur_tp2 = mr->cur_tp;
00258 }
00259 }
00260 }
00261
00262
00263 mi->sample_count *= 4;
00264
00265 cur_prob = 0;
00266 cur_prob_tp = 0;
00267 cur_tp = 0;
00268 cur_tp2 = 0;
00269 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
00270 mg = &mi->groups[group];
00271 if (!mg->supported)
00272 continue;
00273
00274 mr = minstrel_get_ratestats(mi, mg->max_prob_rate);
00275 if (cur_prob_tp < mr->cur_tp &&
00276 minstrel_mcs_groups[group].streams == 1) {
00277 mi->max_prob_rate = mg->max_prob_rate;
00278 cur_prob = mr->cur_prob;
00279 cur_prob_tp = mr->cur_tp;
00280 }
00281
00282 mr = minstrel_get_ratestats(mi, mg->max_tp_rate);
00283 if (cur_tp < mr->cur_tp) {
00284 mi->max_tp_rate2 = mi->max_tp_rate;
00285 cur_tp2 = cur_tp;
00286 mi->max_tp_rate = mg->max_tp_rate;
00287 cur_tp = mr->cur_tp;
00288 }
00289
00290 mr = minstrel_get_ratestats(mi, mg->max_tp_rate2);
00291 if (cur_tp2 < mr->cur_tp) {
00292 mi->max_tp_rate2 = mg->max_tp_rate2;
00293 cur_tp2 = mr->cur_tp;
00294 }
00295 }
00296
00297 mi->stats_update = jiffies;
00298 }
00299
00300 static bool
00301 minstrel_ht_txstat_valid(struct ieee80211_tx_rate *rate)
00302 {
00303 if (!rate->count)
00304 return false;
00305
00306 if (rate->idx < 0)
00307 return false;
00308
00309 return !!(rate->flags & IEEE80211_TX_RC_MCS);
00310 }
00311
00312 static void
00313 minstrel_next_sample_idx(struct minstrel_ht_sta *mi)
00314 {
00315 struct minstrel_mcs_group_data *mg;
00316
00317 for (;;) {
00318 mi->sample_group++;
00319 mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
00320 mg = &mi->groups[mi->sample_group];
00321
00322 if (!mg->supported)
00323 continue;
00324
00325 if (++mg->index >= MCS_GROUP_RATES) {
00326 mg->index = 0;
00327 if (++mg->column >= ARRAY_SIZE(sample_table))
00328 mg->column = 0;
00329 }
00330 break;
00331 }
00332 }
00333
00334 static void
00335 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, unsigned int *idx,
00336 bool primary)
00337 {
00338 int group, orig_group;
00339
00340 orig_group = group = *idx / MCS_GROUP_RATES;
00341 while (group > 0) {
00342 group--;
00343
00344 if (!mi->groups[group].supported)
00345 continue;
00346
00347 if (minstrel_mcs_groups[group].streams >
00348 minstrel_mcs_groups[orig_group].streams)
00349 continue;
00350
00351 if (primary)
00352 *idx = mi->groups[group].max_tp_rate;
00353 else
00354 *idx = mi->groups[group].max_tp_rate2;
00355 break;
00356 }
00357 }
00358
00359 static void
00360 minstrel_aggr_check(struct minstrel_priv *mp, struct ieee80211_sta *pubsta, struct sk_buff *skb)
00361 {
00362 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
00363 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
00364 u16 tid;
00365
00366 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control)))
00367 return;
00368
00369 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE)))
00370 return;
00371
00372 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
00373 if (likely(sta->ampdu_mlme.tid_tx[tid]))
00374 return;
00375
00376 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
00377 return;
00378
00379 ieee80211_start_tx_ba_session(pubsta, tid, 5000);
00380 }
00381
00382 static void
00383 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
00384 struct ieee80211_sta *sta, void *priv_sta,
00385 struct sk_buff *skb)
00386 {
00387 struct minstrel_ht_sta_priv *msp = priv_sta;
00388 struct minstrel_ht_sta *mi = &msp->ht;
00389 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
00390 struct ieee80211_tx_rate *ar = info->status.rates;
00391 struct minstrel_rate_stats *rate, *rate2;
00392 struct minstrel_priv *mp = priv;
00393 bool last = false;
00394 int group;
00395 int i = 0;
00396
00397 if (!msp->is_ht)
00398 return mac80211_minstrel.tx_status(priv, sband, sta, &msp->legacy, skb);
00399
00400
00401 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
00402 !(info->flags & IEEE80211_TX_STAT_AMPDU))
00403 return;
00404
00405 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) {
00406 info->status.ampdu_ack_len =
00407 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0);
00408 info->status.ampdu_len = 1;
00409 }
00410
00411 mi->ampdu_packets++;
00412 mi->ampdu_len += info->status.ampdu_len;
00413
00414 if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
00415 mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
00416 mi->sample_tries = 2;
00417 mi->sample_count--;
00418 }
00419
00420 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
00421 mi->sample_packets += info->status.ampdu_len;
00422
00423 for (i = 0; !last; i++) {
00424 last = (i == IEEE80211_TX_MAX_RATES - 1) ||
00425 !minstrel_ht_txstat_valid(&ar[i + 1]);
00426
00427 if (!minstrel_ht_txstat_valid(&ar[i]))
00428 break;
00429
00430 group = minstrel_ht_get_group_idx(&ar[i]);
00431 rate = &mi->groups[group].rates[ar[i].idx % 8];
00432
00433 if (last)
00434 rate->success += info->status.ampdu_ack_len;
00435
00436 rate->attempts += ar[i].count * info->status.ampdu_len;
00437 }
00438
00439
00440
00441
00442
00443 rate = minstrel_get_ratestats(mi, mi->max_tp_rate);
00444 if (rate->attempts > 30 &&
00445 MINSTREL_FRAC(rate->success, rate->attempts) <
00446 MINSTREL_FRAC(20, 100))
00447 minstrel_downgrade_rate(mi, &mi->max_tp_rate, true);
00448
00449 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate2);
00450 if (rate2->attempts > 30 &&
00451 MINSTREL_FRAC(rate2->success, rate2->attempts) <
00452 MINSTREL_FRAC(20, 100))
00453 minstrel_downgrade_rate(mi, &mi->max_tp_rate2, false);
00454
00455 if (time_after(jiffies, mi->stats_update + (mp->update_interval / 2 * HZ) / 1000)) {
00456 minstrel_ht_update_stats(mp, mi);
00457 if (!(info->flags & IEEE80211_TX_CTL_AMPDU))
00458 minstrel_aggr_check(mp, sta, skb);
00459 }
00460 }
00461
00462 static void
00463 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
00464 int index)
00465 {
00466 struct minstrel_rate_stats *mr;
00467 const struct mcs_group *group;
00468 unsigned int tx_time, tx_time_rtscts, tx_time_data;
00469 unsigned int cw = mp->cw_min;
00470 unsigned int ctime = 0;
00471 unsigned int t_slot = 9;
00472 unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
00473
00474 mr = minstrel_get_ratestats(mi, index);
00475 if (mr->probability < MINSTREL_FRAC(1, 10)) {
00476 mr->retry_count = 1;
00477 mr->retry_count_rtscts = 1;
00478 return;
00479 }
00480
00481 mr->retry_count = 2;
00482 mr->retry_count_rtscts = 2;
00483 mr->retry_updated = true;
00484
00485 group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00486 tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len;
00487
00488
00489 ctime = (t_slot * cw) >> 1;
00490 cw = min((cw << 1) | 1, mp->cw_max);
00491 ctime += (t_slot * cw) >> 1;
00492 cw = min((cw << 1) | 1, mp->cw_max);
00493
00494
00495 tx_time = ctime + 2 * (mi->overhead + tx_time_data);
00496 tx_time_rtscts = ctime + 2 * (mi->overhead_rtscts + tx_time_data);
00497
00498
00499 do {
00500
00501 ctime = (t_slot * cw) >> 1;
00502 cw = min((cw << 1) | 1, mp->cw_max);
00503
00504
00505 tx_time += ctime + mi->overhead + tx_time_data;
00506 tx_time_rtscts += ctime + mi->overhead_rtscts + tx_time_data;
00507
00508 if (tx_time_rtscts < mp->segment_size)
00509 mr->retry_count_rtscts++;
00510 } while ((tx_time < mp->segment_size) &&
00511 (++mr->retry_count < mp->max_retry));
00512 }
00513
00514
00515 static void
00516 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
00517 struct ieee80211_tx_rate *rate, int index,
00518 struct ieee80211_tx_rate_control *txrc,
00519 bool sample, bool rtscts)
00520 {
00521 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00522 struct minstrel_rate_stats *mr;
00523
00524 mr = minstrel_get_ratestats(mi, index);
00525 if (!mr->retry_updated)
00526 minstrel_calc_retransmit(mp, mi, index);
00527
00528 if (sample)
00529 rate->count = 1;
00530 else if (mr->probability < MINSTREL_FRAC(20, 100))
00531 rate->count = 2;
00532 else if (rtscts)
00533 rate->count = mr->retry_count_rtscts;
00534 else
00535 rate->count = mr->retry_count;
00536
00537 rate->flags = IEEE80211_TX_RC_MCS | group->flags;
00538 if (rtscts)
00539 rate->flags |= IEEE80211_TX_RC_USE_RTS_CTS;
00540 rate->idx = index % MCS_GROUP_RATES + (group->streams - 1) * MCS_GROUP_RATES;
00541 }
00542
00543 static inline int
00544 minstrel_get_duration(int index)
00545 {
00546 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
00547 return group->duration[index % MCS_GROUP_RATES];
00548 }
00549
00550 static int
00551 minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
00552 {
00553 struct minstrel_rate_stats *mr;
00554 struct minstrel_mcs_group_data *mg;
00555 int sample_idx = 0;
00556
00557 if (mi->sample_wait > 0) {
00558 mi->sample_wait--;
00559 return -1;
00560 }
00561
00562 if (!mi->sample_tries)
00563 return -1;
00564
00565 mi->sample_tries--;
00566 mg = &mi->groups[mi->sample_group];
00567 sample_idx = sample_table[mg->column][mg->index];
00568 mr = &mg->rates[sample_idx];
00569 sample_idx += mi->sample_group * MCS_GROUP_RATES;
00570 minstrel_next_sample_idx(mi);
00571
00572
00573
00574
00575
00576 if (!mp->has_mrr && (mr->probability > MINSTREL_FRAC(95, 100)))
00577 return -1;
00578
00579
00580
00581
00582
00583 if (minstrel_get_duration(sample_idx) >
00584 minstrel_get_duration(mi->max_tp_rate)) {
00585 if (mr->sample_skipped < 20)
00586 return -1;
00587
00588 if (mi->sample_slow++ > 2)
00589 return -1;
00590 }
00591
00592 return sample_idx;
00593 }
00594
00595 static void
00596 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
00597 struct ieee80211_tx_rate_control *txrc)
00598 {
00599 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
00600 struct ieee80211_tx_rate *ar = info->status.rates;
00601 struct minstrel_ht_sta_priv *msp = priv_sta;
00602 struct minstrel_ht_sta *mi = &msp->ht;
00603 struct minstrel_priv *mp = priv;
00604 int sample_idx;
00605 bool sample = false;
00606
00607 if (rate_control_send_low(sta, priv_sta, txrc))
00608 return;
00609
00610 if (!msp->is_ht)
00611 return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc);
00612
00613 info->flags |= mi->tx_flags;
00614
00615
00616 if (mp->hw->max_rates == 1 &&
00617 txrc->skb->protocol == cpu_to_be16(ETH_P_PAE))
00618 sample_idx = -1;
00619 else
00620 sample_idx = minstrel_get_sample_rate(mp, mi);
00621
00622 #ifdef CONFIG_MAC80211_DEBUGFS
00623
00624 if (mp->fixed_rate_idx != -1)
00625 sample_idx = mp->fixed_rate_idx;
00626 #endif
00627
00628 if (sample_idx >= 0) {
00629 sample = true;
00630 minstrel_ht_set_rate(mp, mi, &ar[0], sample_idx,
00631 txrc, true, false);
00632 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
00633 } else {
00634 minstrel_ht_set_rate(mp, mi, &ar[0], mi->max_tp_rate,
00635 txrc, false, false);
00636 }
00637
00638 if (mp->hw->max_rates >= 3) {
00639
00640
00641
00642
00643
00644 if (sample_idx >= 0)
00645 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate,
00646 txrc, false, false);
00647 else
00648 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_tp_rate2,
00649 txrc, false, true);
00650
00651 minstrel_ht_set_rate(mp, mi, &ar[2], mi->max_prob_rate,
00652 txrc, false, !sample);
00653
00654 ar[3].count = 0;
00655 ar[3].idx = -1;
00656 } else if (mp->hw->max_rates == 2) {
00657
00658
00659
00660
00661
00662 minstrel_ht_set_rate(mp, mi, &ar[1], mi->max_prob_rate,
00663 txrc, false, !sample);
00664
00665 ar[2].count = 0;
00666 ar[2].idx = -1;
00667 } else {
00668
00669 ar[1].count = 0;
00670 ar[1].idx = -1;
00671 }
00672
00673 mi->total_packets++;
00674
00675
00676 if (mi->total_packets == ~0) {
00677 mi->total_packets = 0;
00678 mi->sample_packets = 0;
00679 }
00680 }
00681
00682 static void
00683 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
00684 struct ieee80211_sta *sta, void *priv_sta,
00685 enum nl80211_channel_type oper_chan_type)
00686 {
00687 struct minstrel_priv *mp = priv;
00688 struct minstrel_ht_sta_priv *msp = priv_sta;
00689 struct minstrel_ht_sta *mi = &msp->ht;
00690 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
00691 struct ieee80211_local *local = hw_to_local(mp->hw);
00692 u16 sta_cap = sta->ht_cap.cap;
00693 int n_supported = 0;
00694 int ack_dur;
00695 int stbc;
00696 int i;
00697
00698
00699 if (!sta->ht_cap.ht_supported)
00700 goto use_legacy;
00701
00702 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) !=
00703 MINSTREL_MAX_STREAMS * MINSTREL_STREAM_GROUPS);
00704
00705 msp->is_ht = true;
00706 memset(mi, 0, sizeof(*mi));
00707 mi->stats_update = jiffies;
00708
00709 ack_dur = ieee80211_frame_duration(local, 10, 60, 1, 1);
00710 mi->overhead = ieee80211_frame_duration(local, 0, 60, 1, 1) + ack_dur;
00711 mi->overhead_rtscts = mi->overhead + 2 * ack_dur;
00712
00713 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1);
00714
00715
00716 if (mp->has_mrr) {
00717 mi->sample_count = 16;
00718 mi->sample_wait = 0;
00719 } else {
00720 mi->sample_count = 8;
00721 mi->sample_wait = 8;
00722 }
00723 mi->sample_tries = 4;
00724
00725 stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
00726 IEEE80211_HT_CAP_RX_STBC_SHIFT;
00727 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
00728
00729 if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
00730 mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
00731
00732 if (oper_chan_type != NL80211_CHAN_HT40MINUS &&
00733 oper_chan_type != NL80211_CHAN_HT40PLUS)
00734 sta_cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
00735
00736 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
00737 u16 req = 0;
00738
00739 mi->groups[i].supported = 0;
00740 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_SHORT_GI) {
00741 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
00742 req |= IEEE80211_HT_CAP_SGI_40;
00743 else
00744 req |= IEEE80211_HT_CAP_SGI_20;
00745 }
00746
00747 if (minstrel_mcs_groups[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
00748 req |= IEEE80211_HT_CAP_SUP_WIDTH_20_40;
00749
00750 if ((sta_cap & req) != req)
00751 continue;
00752
00753 mi->groups[i].supported =
00754 mcs->rx_mask[minstrel_mcs_groups[i].streams - 1];
00755
00756 if (mi->groups[i].supported)
00757 n_supported++;
00758 }
00759
00760 if (!n_supported)
00761 goto use_legacy;
00762
00763 return;
00764
00765 use_legacy:
00766 msp->is_ht = false;
00767 memset(&msp->legacy, 0, sizeof(msp->legacy));
00768 msp->legacy.r = msp->ratelist;
00769 msp->legacy.sample_table = msp->sample_table;
00770 return mac80211_minstrel.rate_init(priv, sband, sta, &msp->legacy);
00771 }
00772
00773 static void
00774 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband,
00775 struct ieee80211_sta *sta, void *priv_sta)
00776 {
00777 struct minstrel_priv *mp = priv;
00778
00779 minstrel_ht_update_caps(priv, sband, sta, priv_sta, mp->hw->conf.channel_type);
00780 }
00781
00782 static void
00783 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband,
00784 struct ieee80211_sta *sta, void *priv_sta,
00785 u32 changed, enum nl80211_channel_type oper_chan_type)
00786 {
00787 minstrel_ht_update_caps(priv, sband, sta, priv_sta, oper_chan_type);
00788 }
00789
00790 static void *
00791 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
00792 {
00793 struct ieee80211_supported_band *sband;
00794 struct minstrel_ht_sta_priv *msp;
00795 struct minstrel_priv *mp = priv;
00796 struct ieee80211_hw *hw = mp->hw;
00797 int max_rates = 0;
00798 int i;
00799
00800 for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
00801 sband = hw->wiphy->bands[i];
00802 if (sband && sband->n_bitrates > max_rates)
00803 max_rates = sband->n_bitrates;
00804 }
00805
00806 msp = kzalloc(sizeof(struct minstrel_ht_sta), gfp);
00807 if (!msp)
00808 return NULL;
00809
00810 msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
00811 if (!msp->ratelist)
00812 goto error;
00813
00814 msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
00815 if (!msp->sample_table)
00816 goto error1;
00817
00818 return msp;
00819
00820 error1:
00821 kfree(msp->ratelist);
00822 error:
00823 kfree(msp);
00824 return NULL;
00825 }
00826
00827 static void
00828 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
00829 {
00830 struct minstrel_ht_sta_priv *msp = priv_sta;
00831
00832 kfree(msp->sample_table);
00833 kfree(msp->ratelist);
00834 kfree(msp);
00835 }
00836
00837 static void *
00838 minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
00839 {
00840 return mac80211_minstrel.alloc(hw, debugfsdir);
00841 }
00842
00843 static void
00844 minstrel_ht_free(void *priv)
00845 {
00846 mac80211_minstrel.free(priv);
00847 }
00848
00849 static struct rate_control_ops mac80211_minstrel_ht = {
00850 .name = "minstrel_ht",
00851 .tx_status = minstrel_ht_tx_status,
00852 .get_rate = minstrel_ht_get_rate,
00853 .rate_init = minstrel_ht_rate_init,
00854 .rate_update = minstrel_ht_rate_update,
00855 .alloc_sta = minstrel_ht_alloc_sta,
00856 .free_sta = minstrel_ht_free_sta,
00857 .alloc = minstrel_ht_alloc,
00858 .free = minstrel_ht_free,
00859 #ifdef CONFIG_MAC80211_DEBUGFS
00860 .add_sta_debugfs = minstrel_ht_add_sta_debugfs,
00861 .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
00862 #endif
00863 };
00864
00865
00866 static void
00867 init_sample_table(void)
00868 {
00869 int col, i, new_idx;
00870 u8 rnd[MCS_GROUP_RATES];
00871
00872 memset(sample_table, 0xff, sizeof(sample_table));
00873 for (col = 0; col < SAMPLE_COLUMNS; col++) {
00874 for (i = 0; i < MCS_GROUP_RATES; i++) {
00875 get_random_bytes(rnd, sizeof(rnd));
00876 new_idx = (i + rnd[i]) % MCS_GROUP_RATES;
00877
00878 while (sample_table[col][new_idx] != 0xff)
00879 new_idx = (new_idx + 1) % MCS_GROUP_RATES;
00880
00881 sample_table[col][new_idx] = i;
00882 }
00883 }
00884 }
00885
00886 int __init
00887 rc80211_minstrel_ht_init(void)
00888 {
00889 init_sample_table();
00890 return ieee80211_rate_control_register(&mac80211_minstrel_ht);
00891 }
00892
00893 void
00894 rc80211_minstrel_ht_exit(void)
00895 {
00896 ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
00897 }