package/kernel/mac80211/patches/subsys/371-mac80211-minstrel-merge-with-minstrel_ht-always-enab.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Sat, 10 Feb 2018 12:43:30 +0100
   3 Subject: [PATCH] mac80211: minstrel: merge with minstrel_ht, always enable
   4  VHT support
   5
   6 Legacy-only devices are not very common and the overhead of the extra
   7 code for HT and VHT rates is not big enough to justify all those extra
   8 lines of code to make it optional.
   9
  10 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  11 ---
  12
  13 Index: backports-v4.18-rc7/net/mac80211/Kconfig
  14 ===================================================================
  15 --- backports-v4.18-rc7.orig/net/mac80211/Kconfig
  16 +++ backports-v4.18-rc7/net/mac80211/Kconfig
  17 @@ -25,20 +25,6 @@ config MAC80211_RC_MINSTREL
  18         ---help---
  19           This option enables the 'minstrel' TX rate control algorithm
  20
  21 -config MAC80211_RC_MINSTREL_HT
  22 -       bool "Minstrel 802.11n support" if EXPERT
  23 -       depends on MAC80211_RC_MINSTREL
  24 -       default y
  25 -       ---help---
  26 -         This option enables the 'minstrel_ht' TX rate control algorithm
  27 -
  28 -config MAC80211_RC_MINSTREL_VHT
  29 -       bool "Minstrel 802.11ac support" if EXPERT
  30 -       depends on MAC80211_RC_MINSTREL_HT
  31 -       default n
  32 -       ---help---
  33 -         This option enables VHT in the 'minstrel_ht' TX rate control algorithm
  34 -
  35  choice
  36         prompt "Default rate control algorithm"
  37         depends on MAC80211_HAS_RC
  38 @@ -60,8 +46,7 @@ endchoice
  39
  40  config MAC80211_RC_DEFAULT
  41         string
  42 -       default "minstrel_ht" if MAC80211_RC_DEFAULT_MINSTREL && MAC80211_RC_MINSTREL_HT
  43 -       default "minstrel" if MAC80211_RC_DEFAULT_MINSTREL
  44 +       default "minstrel_ht" if MAC80211_RC_DEFAULT_MINSTREL
  45         default ""
  46
  47  endif
  48 Index: backports-v4.18-rc7/net/mac80211/Makefile
  49 ===================================================================
  50 --- backports-v4.18-rc7.orig/net/mac80211/Makefile
  51 +++ backports-v4.18-rc7/net/mac80211/Makefile
  52 @@ -51,13 +51,14 @@ mac80211-$(CONFIG_PM) += pm.o
  53
  54  CFLAGS_trace.o := -I$(src)
  55
  56 -rc80211_minstrel-y := rc80211_minstrel.o
  57 -rc80211_minstrel-$(CPTCFG_MAC80211_DEBUGFS) += rc80211_minstrel_debugfs.o
  58 +rc80211_minstrel-y := \
  59 +       rc80211_minstrel.o \
  60 +       rc80211_minstrel_ht.o
  61
  62 -rc80211_minstrel_ht-y := rc80211_minstrel_ht.o
  63 -rc80211_minstrel_ht-$(CPTCFG_MAC80211_DEBUGFS) += rc80211_minstrel_ht_debugfs.o
  64 +rc80211_minstrel-$(CPTCFG_MAC80211_DEBUGFS) += \
  65 +       rc80211_minstrel_debugfs.o \
  66 +       rc80211_minstrel_ht_debugfs.o
  67
  68  mac80211-$(CPTCFG_MAC80211_RC_MINSTREL) += $(rc80211_minstrel-y)
  69 -mac80211-$(CPTCFG_MAC80211_RC_MINSTREL_HT) += $(rc80211_minstrel_ht-y)
  70
  71  ccflags-y += -DDEBUG
  72 Index: backports-v4.18-rc7/net/mac80211/main.c
  73 ===================================================================
  74 --- backports-v4.18-rc7.orig/net/mac80211/main.c
  75 +++ backports-v4.18-rc7/net/mac80211/main.c
  76 @@ -1264,18 +1264,12 @@ static int __init ieee80211_init(void)
  77         if (ret)
  78                 return ret;
  79
  80 -       ret = rc80211_minstrel_ht_init();
  81 -       if (ret)
  82 -               goto err_minstrel;
  83 -
  84         ret = ieee80211_iface_init();
  85         if (ret)
  86                 goto err_netdev;
  87
  88         return 0;
  89   err_netdev:
  90 -       rc80211_minstrel_ht_exit();
  91 - err_minstrel:
  92         rc80211_minstrel_exit();
  93
  94         return ret;
  95 @@ -1283,7 +1277,6 @@ static int __init ieee80211_init(void)
  96
  97  static void __exit ieee80211_exit(void)
  98  {
  99 -       rc80211_minstrel_ht_exit();
 100         rc80211_minstrel_exit();
 101
 102         ieee80211s_stop();
 103 Index: backports-v4.18-rc7/net/mac80211/rate.h
 104 ===================================================================
 105 --- backports-v4.18-rc7.orig/net/mac80211/rate.h
 106 +++ backports-v4.18-rc7/net/mac80211/rate.h
 107 @@ -95,18 +95,5 @@ static inline void rc80211_minstrel_exit
 108  }
 109  #endif
 110
 111 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_HT
 112 -int rc80211_minstrel_ht_init(void);
 113 -void rc80211_minstrel_ht_exit(void);
 114 -#else
 115 -static inline int rc80211_minstrel_ht_init(void)
 116 -{
 117 -       return 0;
 118 -}
 119 -static inline void rc80211_minstrel_ht_exit(void)
 120 -{
 121 -}
 122 -#endif
 123 -
 124
 125  #endif /* IEEE80211_RATE_H */
 126 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel.c
 127 ===================================================================
 128 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel.c
 129 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel.c
 130 @@ -572,138 +572,6 @@ minstrel_rate_init(void *priv, struct ie
 131         minstrel_update_rates(mp, mi);
 132  }
 133
 134 -static void *
 135 -minstrel_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
 136 -{
 137 -       struct ieee80211_supported_band *sband;
 138 -       struct minstrel_sta_info *mi;
 139 -       struct minstrel_priv *mp = priv;
 140 -       struct ieee80211_hw *hw = mp->hw;
 141 -       int max_rates = 0;
 142 -       int i;
 143 -
 144 -       mi = kzalloc(sizeof(struct minstrel_sta_info), gfp);
 145 -       if (!mi)
 146 -               return NULL;
 147 -
 148 -       for (i = 0; i < NUM_NL80211_BANDS; i++) {
 149 -               sband = hw->wiphy->bands[i];
 150 -               if (sband && sband->n_bitrates > max_rates)
 151 -                       max_rates = sband->n_bitrates;
 152 -       }
 153 -
 154 -       mi->r = kcalloc(max_rates, sizeof(struct minstrel_rate), gfp);
 155 -       if (!mi->r)
 156 -               goto error;
 157 -
 158 -       mi->sample_table = kmalloc_array(max_rates, SAMPLE_COLUMNS, gfp);
 159 -       if (!mi->sample_table)
 160 -               goto error1;
 161 -
 162 -       mi->last_stats_update = jiffies;
 163 -       return mi;
 164 -
 165 -error1:
 166 -       kfree(mi->r);
 167 -error:
 168 -       kfree(mi);
 169 -       return NULL;
 170 -}
 171 -
 172 -static void
 173 -minstrel_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
 174 -{
 175 -       struct minstrel_sta_info *mi = priv_sta;
 176 -
 177 -       kfree(mi->sample_table);
 178 -       kfree(mi->r);
 179 -       kfree(mi);
 180 -}
 181 -
 182 -static void
 183 -minstrel_init_cck_rates(struct minstrel_priv *mp)
 184 -{
 185 -       static const int bitrates[4] = { 10, 20, 55, 110 };
 186 -       struct ieee80211_supported_band *sband;
 187 -       u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef);
 188 -       int i, j;
 189 -
 190 -       sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ];
 191 -       if (!sband)
 192 -               return;
 193 -
 194 -       for (i = 0, j = 0; i < sband->n_bitrates; i++) {
 195 -               struct ieee80211_rate *rate = &sband->bitrates[i];
 196 -
 197 -               if (rate->flags & IEEE80211_RATE_ERP_G)
 198 -                       continue;
 199 -
 200 -               if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 201 -                       continue;
 202 -
 203 -               for (j = 0; j < ARRAY_SIZE(bitrates); j++) {
 204 -                       if (rate->bitrate != bitrates[j])
 205 -                               continue;
 206 -
 207 -                       mp->cck_rates[j] = i;
 208 -                       break;
 209 -               }
 210 -       }
 211 -}
 212 -
 213 -static void *
 214 -minstrel_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
 215 -{
 216 -       struct minstrel_priv *mp;
 217 -
 218 -       mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
 219 -       if (!mp)
 220 -               return NULL;
 221 -
 222 -       /* contention window settings
 223 -        * Just an approximation. Using the per-queue values would complicate
 224 -        * the calculations and is probably unnecessary */
 225 -       mp->cw_min = 15;
 226 -       mp->cw_max = 1023;
 227 -
 228 -       /* number of packets (in %) to use for sampling other rates
 229 -        * sample less often for non-mrr packets, because the overhead
 230 -        * is much higher than with mrr */
 231 -       mp->lookaround_rate = 5;
 232 -       mp->lookaround_rate_mrr = 10;
 233 -
 234 -       /* maximum time that the hw is allowed to stay in one MRR segment */
 235 -       mp->segment_size = 6000;
 236 -
 237 -       if (hw->max_rate_tries > 0)
 238 -               mp->max_retry = hw->max_rate_tries;
 239 -       else
 240 -               /* safe default, does not necessarily have to match hw properties */
 241 -               mp->max_retry = 7;
 242 -
 243 -       if (hw->max_rates >= 4)
 244 -               mp->has_mrr = true;
 245 -
 246 -       mp->hw = hw;
 247 -       mp->update_interval = 100;
 248 -
 249 -#ifdef CPTCFG_MAC80211_DEBUGFS
 250 -       mp->fixed_rate_idx = (u32) -1;
 251 -       debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir,
 252 -                          &mp->fixed_rate_idx);
 253 -#endif
 254 -
 255 -       minstrel_init_cck_rates(mp);
 256 -
 257 -       return mp;
 258 -}
 259 -
 260 -static void
 261 -minstrel_free(void *priv)
 262 -{
 263 -       kfree(priv);
 264 -}
 265 -
 266  static u32 minstrel_get_expected_throughput(void *priv_sta)
 267  {
 268         struct minstrel_sta_info *mi = priv_sta;
 269 @@ -722,29 +590,8 @@ static u32 minstrel_get_expected_through
 270  }
 271
 272  const struct rate_control_ops mac80211_minstrel = {
 273 -       .name = "minstrel",
 274         .tx_status_ext = minstrel_tx_status,
 275         .get_rate = minstrel_get_rate,
 276         .rate_init = minstrel_rate_init,
 277 -       .alloc = minstrel_alloc,
 278 -       .free = minstrel_free,
 279 -       .alloc_sta = minstrel_alloc_sta,
 280 -       .free_sta = minstrel_free_sta,
 281 -#ifdef CPTCFG_MAC80211_DEBUGFS
 282 -       .add_sta_debugfs = minstrel_add_sta_debugfs,
 283 -#endif
 284         .get_expected_throughput = minstrel_get_expected_throughput,
 285  };
 286 -
 287 -int __init
 288 -rc80211_minstrel_init(void)
 289 -{
 290 -       return ieee80211_rate_control_register(&mac80211_minstrel);
 291 -}
 292 -
 293 -void
 294 -rc80211_minstrel_exit(void)
 295 -{
 296 -       ieee80211_rate_control_unregister(&mac80211_minstrel);
 297 -}
 298 -
 299 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel.h
 300 ===================================================================
 301 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel.h
 302 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel.h
 303 @@ -158,7 +158,5 @@ int minstrel_get_tp_avg(struct minstrel_
 304  /* debugfs */
 305  int minstrel_stats_open(struct inode *inode, struct file *file);
 306  int minstrel_stats_csv_open(struct inode *inode, struct file *file);
 307 -ssize_t minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos);
 308 -int minstrel_stats_release(struct inode *inode, struct file *file);
 309
 310  #endif
 311 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel_debugfs.c
 312 ===================================================================
 313 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel_debugfs.c
 314 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel_debugfs.c
 315 @@ -54,22 +54,6 @@
 316  #include <net/mac80211.h>
 317  #include "rc80211_minstrel.h"
 318
 319 -ssize_t
 320 -minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos)
 321 -{
 322 -       struct minstrel_debugfs_info *ms;
 323 -
 324 -       ms = file->private_data;
 325 -       return simple_read_from_buffer(buf, len, ppos, ms->buf, ms->len);
 326 -}
 327 -
 328 -int
 329 -minstrel_stats_release(struct inode *inode, struct file *file)
 330 -{
 331 -       kfree(file->private_data);
 332 -       return 0;
 333 -}
 334 -
 335  int
 336  minstrel_stats_open(struct inode *inode, struct file *file)
 337  {
 338 @@ -135,14 +119,6 @@ minstrel_stats_open(struct inode *inode,
 339         return 0;
 340  }
 341
 342 -static const struct file_operations minstrel_stat_fops = {
 343 -       .owner = THIS_MODULE,
 344 -       .open = minstrel_stats_open,
 345 -       .read = minstrel_stats_read,
 346 -       .release = minstrel_stats_release,
 347 -       .llseek = default_llseek,
 348 -};
 349 -
 350  int
 351  minstrel_stats_csv_open(struct inode *inode, struct file *file)
 352  {
 353 @@ -200,21 +176,3 @@ minstrel_stats_csv_open(struct inode *in
 354
 355         return 0;
 356  }
 357 -
 358 -static const struct file_operations minstrel_stat_csv_fops = {
 359 -       .owner = THIS_MODULE,
 360 -       .open = minstrel_stats_csv_open,
 361 -       .read = minstrel_stats_read,
 362 -       .release = minstrel_stats_release,
 363 -       .llseek = default_llseek,
 364 -};
 365 -
 366 -void
 367 -minstrel_add_sta_debugfs(void *priv, void *priv_sta, struct dentry *dir)
 368 -{
 369 -       struct minstrel_sta_info *mi = priv_sta;
 370 -
 371 -       debugfs_create_file("rc_stats", S_IRUGO, dir, mi, &minstrel_stat_fops);
 372 -       debugfs_create_file("rc_stats_csv", S_IRUGO, dir, mi,
 373 -                           &minstrel_stat_csv_fops);
 374 -}
 375 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht.c
 376 ===================================================================
 377 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel_ht.c
 378 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht.c
 379 @@ -137,12 +137,10 @@
 380                 }                                       \
 381         }
 382
 383 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 384  static bool minstrel_vht_only = true;
 385  module_param(minstrel_vht_only, bool, 0644);
 386  MODULE_PARM_DESC(minstrel_vht_only,
 387                  "Use only VHT rates when VHT is supported by sta.");
 388 -#endif
 389
 390  /*
 391   * To enable sufficiently targeted rate sampling, MCS rates are divided into
 392 @@ -171,7 +169,6 @@ const struct mcs_group minstrel_mcs_grou
 393
 394         CCK_GROUP,
 395
 396 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 397         VHT_GROUP(1, 0, BW_20),
 398         VHT_GROUP(2, 0, BW_20),
 399         VHT_GROUP(3, 0, BW_20),
 400 @@ -195,7 +192,6 @@ const struct mcs_group minstrel_mcs_grou
 401         VHT_GROUP(1, 1, BW_80),
 402         VHT_GROUP(2, 1, BW_80),
 403         VHT_GROUP(3, 1, BW_80),
 404 -#endif
 405  };
 406
 407  static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
 408 @@ -1146,12 +1142,10 @@ minstrel_ht_update_caps(void *priv, stru
 409
 410         BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB);
 411
 412 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 413         if (vht_cap->vht_supported)
 414                 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0);
 415         else
 416 -#endif
 417 -       use_vht = 0;
 418 +               use_vht = 0;
 419
 420         msp->is_ht = true;
 421         memset(mi, 0, sizeof(*mi));
 422 @@ -1226,10 +1220,9 @@ minstrel_ht_update_caps(void *priv, stru
 423
 424                 /* HT rate */
 425                 if (gflags & IEEE80211_TX_RC_MCS) {
 426 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 427                         if (use_vht && minstrel_vht_only)
 428                                 continue;
 429 -#endif
 430 +
 431                         mi->supported[i] = mcs->rx_mask[nss - 1];
 432                         if (mi->supported[i])
 433                                 n_supported++;
 434 @@ -1349,16 +1342,88 @@ minstrel_ht_free_sta(void *priv, struct
 435         kfree(msp);
 436  }
 437
 438 +static void
 439 +minstrel_ht_init_cck_rates(struct minstrel_priv *mp)
 440 +{
 441 +       static const int bitrates[4] = { 10, 20, 55, 110 };
 442 +       struct ieee80211_supported_band *sband;
 443 +       u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef);
 444 +       int i, j;
 445 +
 446 +       sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ];
 447 +       if (!sband)
 448 +               return;
 449 +
 450 +       for (i = 0, j = 0; i < sband->n_bitrates; i++) {
 451 +               struct ieee80211_rate *rate = &sband->bitrates[i];
 452 +
 453 +               if (rate->flags & IEEE80211_RATE_ERP_G)
 454 +                       continue;
 455 +
 456 +               if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 457 +                       continue;
 458 +
 459 +               for (j = 0; j < ARRAY_SIZE(bitrates); j++) {
 460 +                       if (rate->bitrate != bitrates[j])
 461 +                               continue;
 462 +
 463 +                       mp->cck_rates[j] = i;
 464 +                       break;
 465 +               }
 466 +       }
 467 +}
 468 +
 469  static void *
 470  minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
 471  {
 472 -       return mac80211_minstrel.alloc(hw, debugfsdir);
 473 +       struct minstrel_priv *mp;
 474 +
 475 +       mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC);
 476 +       if (!mp)
 477 +               return NULL;
 478 +
 479 +       /* contention window settings
 480 +        * Just an approximation. Using the per-queue values would complicate
 481 +        * the calculations and is probably unnecessary */
 482 +       mp->cw_min = 15;
 483 +       mp->cw_max = 1023;
 484 +
 485 +       /* number of packets (in %) to use for sampling other rates
 486 +        * sample less often for non-mrr packets, because the overhead
 487 +        * is much higher than with mrr */
 488 +       mp->lookaround_rate = 5;
 489 +       mp->lookaround_rate_mrr = 10;
 490 +
 491 +       /* maximum time that the hw is allowed to stay in one MRR segment */
 492 +       mp->segment_size = 6000;
 493 +
 494 +       if (hw->max_rate_tries > 0)
 495 +               mp->max_retry = hw->max_rate_tries;
 496 +       else
 497 +               /* safe default, does not necessarily have to match hw properties */
 498 +               mp->max_retry = 7;
 499 +
 500 +       if (hw->max_rates >= 4)
 501 +               mp->has_mrr = true;
 502 +
 503 +       mp->hw = hw;
 504 +       mp->update_interval = 100;
 505 +
 506 +#ifdef CPTCFG_MAC80211_DEBUGFS
 507 +       mp->fixed_rate_idx = (u32) -1;
 508 +       debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir,
 509 +                          &mp->fixed_rate_idx);
 510 +#endif
 511 +
 512 +       minstrel_ht_init_cck_rates(mp);
 513 +
 514 +       return mp;
 515  }
 516
 517  static void
 518  minstrel_ht_free(void *priv)
 519  {
 520 -       mac80211_minstrel.free(priv);
 521 +       kfree(priv);
 522  }
 523
 524  static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
 525 @@ -1417,14 +1482,14 @@ static void __init init_sample_table(voi
 526  }
 527
 528  int __init
 529 -rc80211_minstrel_ht_init(void)
 530 +rc80211_minstrel_init(void)
 531  {
 532         init_sample_table();
 533         return ieee80211_rate_control_register(&mac80211_minstrel_ht);
 534  }
 535
 536  void
 537 -rc80211_minstrel_ht_exit(void)
 538 +rc80211_minstrel_exit(void)
 539  {
 540         ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
 541  }
 542 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht.h
 543 ===================================================================
 544 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel_ht.h
 545 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht.h
 546 @@ -15,11 +15,7 @@
 547   */
 548  #define MINSTREL_MAX_STREAMS           3
 549  #define MINSTREL_HT_STREAM_GROUPS      4 /* BW(=2) * SGI(=2) */
 550 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 551  #define MINSTREL_VHT_STREAM_GROUPS     6 /* BW(=3) * SGI(=2) */
 552 -#else
 553 -#define MINSTREL_VHT_STREAM_GROUPS     0
 554 -#endif
 555
 556  #define MINSTREL_HT_GROUPS_NB  (MINSTREL_MAX_STREAMS *         \
 557                                  MINSTREL_HT_STREAM_GROUPS)
 558 @@ -34,11 +30,7 @@
 559  #define MINSTREL_CCK_GROUP     (MINSTREL_HT_GROUP_0 + MINSTREL_HT_GROUPS_NB)
 560  #define MINSTREL_VHT_GROUP_0   (MINSTREL_CCK_GROUP + 1)
 561
 562 -#ifdef CPTCFG_MAC80211_RC_MINSTREL_VHT
 563  #define MCS_GROUP_RATES                10
 564 -#else
 565 -#define MCS_GROUP_RATES                8
 566 -#endif
 567
 568  struct mcs_group {
 569         u32 flags;
 570 Index: backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht_debugfs.c
 571 ===================================================================
 572 --- backports-v4.18-rc7.orig/net/mac80211/rc80211_minstrel_ht_debugfs.c
 573 +++ backports-v4.18-rc7/net/mac80211/rc80211_minstrel_ht_debugfs.c
 574 @@ -15,6 +15,22 @@
 575  #include "rc80211_minstrel.h"
 576  #include "rc80211_minstrel_ht.h"
 577
 578 +static ssize_t
 579 +minstrel_stats_read(struct file *file, char __user *buf, size_t len, loff_t *ppos)
 580 +{
 581 +       struct minstrel_debugfs_info *ms;
 582 +
 583 +       ms = file->private_data;
 584 +       return simple_read_from_buffer(buf, len, ppos, ms->buf, ms->len);
 585 +}
 586 +
 587 +static int
 588 +minstrel_stats_release(struct inode *inode, struct file *file)
 589 +{
 590 +       kfree(file->private_data);
 591 +       return 0;
 592 +}
 593 +
 594  static char *
 595  minstrel_ht_stats_dump(struct minstrel_ht_sta *mi, int i, char *p)
 596  {