drivers/net/wireless/ath/wil6210/rx_reorder.c

   1 /*
   2  * Copyright (c) 2014-2015 Qualcomm Atheros, Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include "wil6210.h"
  18 #include "txrx.h"
  19
  20 #define SEQ_MODULO 0x1000
  21 #define SEQ_MASK   0xfff
  22
  23 static inline int seq_less(u16 sq1, u16 sq2)
  24 {
  25         return ((sq1 - sq2) & SEQ_MASK) > (SEQ_MODULO >> 1);
  26 }
  27
  28 static inline u16 seq_inc(u16 sq)
  29 {
  30         return (sq + 1) & SEQ_MASK;
  31 }
  32
  33 static inline u16 seq_sub(u16 sq1, u16 sq2)
  34 {
  35         return (sq1 - sq2) & SEQ_MASK;
  36 }
  37
  38 static inline int reorder_index(struct wil_tid_ampdu_rx *r, u16 seq)
  39 {
  40         return seq_sub(seq, r->ssn) % r->buf_size;
  41 }
  42
  43 static void wil_release_reorder_frame(struct wil6210_priv *wil,
  44                                       struct wil_tid_ampdu_rx *r,
  45                                       int index)
  46 {
  47         struct net_device *ndev = wil_to_ndev(wil);
  48         struct sk_buff *skb = r->reorder_buf[index];
  49
  50         if (!skb)
  51                 goto no_frame;
  52
  53         /* release the frame from the reorder ring buffer */
  54         r->stored_mpdu_num--;
  55         r->reorder_buf[index] = NULL;
  56         wil_netif_rx_any(skb, ndev);
  57
  58 no_frame:
  59         r->head_seq_num = seq_inc(r->head_seq_num);
  60 }
  61
  62 static void wil_release_reorder_frames(struct wil6210_priv *wil,
  63                                        struct wil_tid_ampdu_rx *r,
  64                                        u16 hseq)
  65 {
  66         int index;
  67
  68         /* note: this function is never called with
  69          * hseq preceding r->head_seq_num, i.e it is always true
  70          * !seq_less(hseq, r->head_seq_num)
  71          * and thus on loop exit it should be
  72          * r->head_seq_num == hseq
  73          */
  74         while (seq_less(r->head_seq_num, hseq) && r->stored_mpdu_num) {
  75                 index = reorder_index(r, r->head_seq_num);
  76                 wil_release_reorder_frame(wil, r, index);
  77         }
  78         r->head_seq_num = hseq;
  79 }
  80
  81 static void wil_reorder_release(struct wil6210_priv *wil,
  82                                 struct wil_tid_ampdu_rx *r)
  83 {
  84         int index = reorder_index(r, r->head_seq_num);
  85
  86         while (r->reorder_buf[index]) {
  87                 wil_release_reorder_frame(wil, r, index);
  88                 index = reorder_index(r, r->head_seq_num);
  89         }
  90 }
  91
  92 /* called in NAPI context */
  93 void wil_rx_reorder(struct wil6210_priv *wil, struct sk_buff *skb)
  94 __acquires(&sta->tid_rx_lock) __releases(&sta->tid_rx_lock)
  95 {
  96         struct net_device *ndev = wil_to_ndev(wil);
  97         struct vring_rx_desc *d = wil_skb_rxdesc(skb);
  98         int tid = wil_rxdesc_tid(d);
  99         int cid = wil_rxdesc_cid(d);
 100         int mid = wil_rxdesc_mid(d);
 101         u16 seq = wil_rxdesc_seq(d);
 102         int mcast = wil_rxdesc_mcast(d);
 103         struct wil_sta_info *sta = &wil->sta[cid];
 104         struct wil_tid_ampdu_rx *r;
 105         u16 hseq;
 106         int index;
 107
 108         wil_dbg_txrx(wil, "MID %d CID %d TID %d Seq 0x%03x mcast %01x\n",
 109                      mid, cid, tid, seq, mcast);
 110
 111         if (unlikely(mcast)) {
 112                 wil_netif_rx_any(skb, ndev);
 113                 return;
 114         }
 115
 116         spin_lock(&sta->tid_rx_lock);
 117
 118         r = sta->tid_rx[tid];
 119         if (!r) {
 120                 wil_netif_rx_any(skb, ndev);
 121                 goto out;
 122         }
 123
 124         r->total++;
 125         hseq = r->head_seq_num;
 126
 127         /** Due to the race between WMI events, where BACK establishment
 128          * reported, and data Rx, few packets may be pass up before reorder
 129          * buffer get allocated. Catch up by pretending SSN is what we
 130          * see in the 1-st Rx packet
 131          *
 132          * Another scenario, Rx get delayed and we got packet from before
 133          * BACK. Pass it to the stack and wait.
 134          */
 135         if (r->first_time) {
 136                 r->first_time = false;
 137                 if (seq != r->head_seq_num) {
 138                         if (seq_less(seq, r->head_seq_num)) {
 139                                 wil_err(wil,
 140                                         "Error: frame with early sequence 0x%03x, should be 0x%03x. Waiting...\n",
 141                                         seq, r->head_seq_num);
 142                                 r->first_time = true;
 143                                 wil_netif_rx_any(skb, ndev);
 144                                 goto out;
 145                         }
 146                         wil_err(wil,
 147                                 "Error: 1-st frame with wrong sequence 0x%03x, should be 0x%03x. Fixing...\n",
 148                                 seq, r->head_seq_num);
 149                         r->head_seq_num = seq;
 150                         r->ssn = seq;
 151                 }
 152         }
 153
 154         /* frame with out of date sequence number */
 155         if (seq_less(seq, r->head_seq_num)) {
 156                 r->ssn_last_drop = seq;
 157                 r->drop_old++;
 158                 wil_dbg_txrx(wil, "Rx drop: old seq 0x%03x head 0x%03x\n",
 159                              seq, r->head_seq_num);
 160                 dev_kfree_skb(skb);
 161                 goto out;
 162         }
 163
 164         /*
 165          * If frame the sequence number exceeds our buffering window
 166          * size release some previous frames to make room for this one.
 167          */
 168         if (!seq_less(seq, r->head_seq_num + r->buf_size)) {
 169                 hseq = seq_inc(seq_sub(seq, r->buf_size));
 170                 /* release stored frames up to new head to stack */
 171                 wil_release_reorder_frames(wil, r, hseq);
 172         }
 173
 174         /* Now the new frame is always in the range of the reordering buffer */
 175
 176         index = reorder_index(r, seq);
 177
 178         /* check if we already stored this frame */
 179         if (r->reorder_buf[index]) {
 180                 r->drop_dup++;
 181                 wil_dbg_txrx(wil, "Rx drop: dup seq 0x%03x\n", seq);
 182                 dev_kfree_skb(skb);
 183                 goto out;
 184         }
 185
 186         /*
 187          * If the current MPDU is in the right order and nothing else
 188          * is stored we can process it directly, no need to buffer it.
 189          * If it is first but there's something stored, we may be able
 190          * to release frames after this one.
 191          */
 192         if (seq == r->head_seq_num && r->stored_mpdu_num == 0) {
 193                 r->head_seq_num = seq_inc(r->head_seq_num);
 194                 wil_netif_rx_any(skb, ndev);
 195                 goto out;
 196         }
 197
 198         /* put the frame in the reordering buffer */
 199         r->reorder_buf[index] = skb;
 200         r->reorder_time[index] = jiffies;
 201         r->stored_mpdu_num++;
 202         wil_reorder_release(wil, r);
 203
 204 out:
 205         spin_unlock(&sta->tid_rx_lock);
 206 }
 207
 208 struct wil_tid_ampdu_rx *wil_tid_ampdu_rx_alloc(struct wil6210_priv *wil,
 209                                                 int size, u16 ssn)
 210 {
 211         struct wil_tid_ampdu_rx *r = kzalloc(sizeof(*r), GFP_KERNEL);
 212
 213         if (!r)
 214                 return NULL;
 215
 216         r->reorder_buf =
 217                 kcalloc(size, sizeof(struct sk_buff *), GFP_KERNEL);
 218         r->reorder_time =
 219                 kcalloc(size, sizeof(unsigned long), GFP_KERNEL);
 220         if (!r->reorder_buf || !r->reorder_time) {
 221                 kfree(r->reorder_buf);
 222                 kfree(r->reorder_time);
 223                 kfree(r);
 224                 return NULL;
 225         }
 226
 227         r->ssn = ssn;
 228         r->head_seq_num = ssn;
 229         r->buf_size = size;
 230         r->stored_mpdu_num = 0;
 231         r->first_time = true;
 232         return r;
 233 }
 234
 235 void wil_tid_ampdu_rx_free(struct wil6210_priv *wil,
 236                            struct wil_tid_ampdu_rx *r)
 237 {
 238         if (!r)
 239                 return;
 240         wil_release_reorder_frames(wil, r, r->head_seq_num + r->buf_size);
 241         kfree(r->reorder_buf);
 242         kfree(r->reorder_time);
 243         kfree(r);
 244 }
 245
 246 /* ADDBA processing */
 247 static u16 wil_agg_size(struct wil6210_priv *wil, u16 req_agg_wsize)
 248 {
 249         u16 max_agg_size = min_t(u16, WIL_MAX_AGG_WSIZE, WIL_MAX_AMPDU_SIZE /
 250                                  (mtu_max + WIL_MAX_MPDU_OVERHEAD));
 251
 252         if (!req_agg_wsize)
 253                 return max_agg_size;
 254
 255         return min(max_agg_size, req_agg_wsize);
 256 }
 257
 258 /* Block Ack - Rx side (recipient */
 259 int wil_addba_rx_request(struct wil6210_priv *wil, u8 cidxtid,
 260                          u8 dialog_token, __le16 ba_param_set,
 261                          __le16 ba_timeout, __le16 ba_seq_ctrl)
 262 {
 263         struct wil_back_rx *req = kzalloc(sizeof(*req), GFP_KERNEL);
 264
 265         if (!req)
 266                 return -ENOMEM;
 267
 268         req->cidxtid = cidxtid;
 269         req->dialog_token = dialog_token;
 270         req->ba_param_set = le16_to_cpu(ba_param_set);
 271         req->ba_timeout = le16_to_cpu(ba_timeout);
 272         req->ba_seq_ctrl = le16_to_cpu(ba_seq_ctrl);
 273
 274         mutex_lock(&wil->back_rx_mutex);
 275         list_add_tail(&req->list, &wil->back_rx_pending);
 276         mutex_unlock(&wil->back_rx_mutex);
 277
 278         queue_work(wil->wq_service, &wil->back_rx_worker);
 279
 280         return 0;
 281 }
 282
 283 static void wil_back_rx_handle(struct wil6210_priv *wil,
 284                                struct wil_back_rx *req)
 285 __acquires(&sta->tid_rx_lock) __releases(&sta->tid_rx_lock)
 286 {
 287         struct wil_sta_info *sta;
 288         u8 cid, tid;
 289         u16 agg_wsize = 0;
 290         /* bit 0: A-MSDU supported
 291          * bit 1: policy (should be 0 for us)
 292          * bits 2..5: TID
 293          * bits 6..15: buffer size
 294          */
 295         u16 req_agg_wsize = WIL_GET_BITS(req->ba_param_set, 6, 15);
 296         bool agg_amsdu = !!(req->ba_param_set & BIT(0));
 297         int ba_policy = req->ba_param_set & BIT(1);
 298         u16 agg_timeout = req->ba_timeout;
 299         u16 status = WLAN_STATUS_SUCCESS;
 300         u16 ssn = req->ba_seq_ctrl >> 4;
 301         struct wil_tid_ampdu_rx *r;
 302         int rc;
 303
 304         might_sleep();
 305         parse_cidxtid(req->cidxtid, &cid, &tid);
 306
 307         /* sanity checks */
 308         if (cid >= WIL6210_MAX_CID) {
 309                 wil_err(wil, "BACK: invalid CID %d\n", cid);
 310                 return;
 311         }
 312
 313         sta = &wil->sta[cid];
 314         if (sta->status != wil_sta_connected) {
 315                 wil_err(wil, "BACK: CID %d not connected\n", cid);
 316                 return;
 317         }
 318
 319         wil_dbg_wmi(wil,
 320                     "ADDBA request for CID %d %pM TID %d size %d timeout %d AMSDU%s policy %d token %d SSN 0x%03x\n",
 321                     cid, sta->addr, tid, req_agg_wsize, req->ba_timeout,
 322                     agg_amsdu ? "+" : "-", !!ba_policy, req->dialog_token, ssn);
 323
 324         /* apply policies */
 325         if (ba_policy) {
 326                 wil_err(wil, "BACK requested unsupported ba_policy == 1\n");
 327                 status = WLAN_STATUS_INVALID_QOS_PARAM;
 328         }
 329         if (status == WLAN_STATUS_SUCCESS)
 330                 agg_wsize = wil_agg_size(wil, req_agg_wsize);
 331
 332         rc = wmi_addba_rx_resp(wil, cid, tid, req->dialog_token, status,
 333                                agg_amsdu, agg_wsize, agg_timeout);
 334         if (rc || (status != WLAN_STATUS_SUCCESS))
 335                 return;
 336
 337         /* apply */
 338         r = wil_tid_ampdu_rx_alloc(wil, agg_wsize, ssn);
 339         spin_lock_bh(&sta->tid_rx_lock);
 340         wil_tid_ampdu_rx_free(wil, sta->tid_rx[tid]);
 341         sta->tid_rx[tid] = r;
 342         spin_unlock_bh(&sta->tid_rx_lock);
 343 }
 344
 345 void wil_back_rx_flush(struct wil6210_priv *wil)
 346 {
 347         struct wil_back_rx *evt, *t;
 348
 349         wil_dbg_misc(wil, "%s()\n", __func__);
 350
 351         mutex_lock(&wil->back_rx_mutex);
 352
 353         list_for_each_entry_safe(evt, t, &wil->back_rx_pending, list) {
 354                 list_del(&evt->list);
 355                 kfree(evt);
 356         }
 357
 358         mutex_unlock(&wil->back_rx_mutex);
 359 }
 360
 361 /* Retrieve next ADDBA request from the pending list */
 362 static struct list_head *next_back_rx(struct wil6210_priv *wil)
 363 {
 364         struct list_head *ret = NULL;
 365
 366         mutex_lock(&wil->back_rx_mutex);
 367
 368         if (!list_empty(&wil->back_rx_pending)) {
 369                 ret = wil->back_rx_pending.next;
 370                 list_del(ret);
 371         }
 372
 373         mutex_unlock(&wil->back_rx_mutex);
 374
 375         return ret;
 376 }
 377
 378 void wil_back_rx_worker(struct work_struct *work)
 379 {
 380         struct wil6210_priv *wil = container_of(work, struct wil6210_priv,
 381                                                 back_rx_worker);
 382         struct wil_back_rx *evt;
 383         struct list_head *lh;
 384
 385         while ((lh = next_back_rx(wil)) != NULL) {
 386                 evt = list_entry(lh, struct wil_back_rx, list);
 387
 388                 wil_back_rx_handle(wil, evt);
 389                 kfree(evt);
 390         }
 391 }
 392
 393 /* BACK - Tx (originator) side */
 394 static void wil_back_tx_handle(struct wil6210_priv *wil,
 395                                struct wil_back_tx *req)
 396 {
 397         struct vring_tx_data *txdata = &wil->vring_tx_data[req->ringid];
 398         int rc;
 399
 400         if (txdata->addba_in_progress) {
 401                 wil_dbg_misc(wil, "ADDBA for vring[%d] already in progress\n",
 402                              req->ringid);
 403                 return;
 404         }
 405         if (txdata->agg_wsize) {
 406                 wil_dbg_misc(wil,
 407                              "ADDBA for vring[%d] already established wsize %d\n",
 408                              req->ringid, txdata->agg_wsize);
 409                 return;
 410         }
 411         txdata->addba_in_progress = true;
 412         rc = wmi_addba(wil, req->ringid, req->agg_wsize, req->agg_timeout);
 413         if (rc)
 414                 txdata->addba_in_progress = false;
 415 }
 416
 417 static struct list_head *next_back_tx(struct wil6210_priv *wil)
 418 {
 419         struct list_head *ret = NULL;
 420
 421         mutex_lock(&wil->back_tx_mutex);
 422
 423         if (!list_empty(&wil->back_tx_pending)) {
 424                 ret = wil->back_tx_pending.next;
 425                 list_del(ret);
 426         }
 427
 428         mutex_unlock(&wil->back_tx_mutex);
 429
 430         return ret;
 431 }
 432
 433 void wil_back_tx_worker(struct work_struct *work)
 434 {
 435         struct wil6210_priv *wil = container_of(work, struct wil6210_priv,
 436                                                  back_tx_worker);
 437         struct wil_back_tx *evt;
 438         struct list_head *lh;
 439
 440         while ((lh = next_back_tx(wil)) != NULL) {
 441                 evt = list_entry(lh, struct wil_back_tx, list);
 442
 443                 wil_back_tx_handle(wil, evt);
 444                 kfree(evt);
 445         }
 446 }
 447
 448 void wil_back_tx_flush(struct wil6210_priv *wil)
 449 {
 450         struct wil_back_tx *evt, *t;
 451
 452         wil_dbg_misc(wil, "%s()\n", __func__);
 453
 454         mutex_lock(&wil->back_tx_mutex);
 455
 456         list_for_each_entry_safe(evt, t, &wil->back_tx_pending, list) {
 457                 list_del(&evt->list);
 458                 kfree(evt);
 459         }
 460
 461         mutex_unlock(&wil->back_tx_mutex);
 462 }
 463
 464 int wil_addba_tx_request(struct wil6210_priv *wil, u8 ringid, u16 wsize)
 465 {
 466         struct wil_back_tx *req = kzalloc(sizeof(*req), GFP_KERNEL);
 467
 468         if (!req)
 469                 return -ENOMEM;
 470
 471         req->ringid = ringid;
 472         req->agg_wsize = wil_agg_size(wil, wsize);
 473         req->agg_timeout = 0;
 474
 475         mutex_lock(&wil->back_tx_mutex);
 476         list_add_tail(&req->list, &wil->back_tx_pending);
 477         mutex_unlock(&wil->back_tx_mutex);
 478
 479         queue_work(wil->wq_service, &wil->back_tx_worker);
 480
 481         return 0;
 482 }