kernel/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         hseq = r->head_seq_num;
 125
 126         /** Due to the race between WMI events, where BACK establishment
 127          * reported, and data Rx, few packets may be pass up before reorder
 128          * buffer get allocated. Catch up by pretending SSN is what we
 129          * see in the 1-st Rx packet
 130          *
 131          * Another scenario, Rx get delayed and we got packet from before
 132          * BACK. Pass it to the stack and wait.
 133          */
 134         if (r->first_time) {
 135                 r->first_time = false;
 136                 if (seq != r->head_seq_num) {
 137                         if (seq_less(seq, r->head_seq_num)) {
 138                                 wil_err(wil,
 139                                         "Error: frame with early sequence 0x%03x, should be 0x%03x. Waiting...\n",
 140                                         seq, r->head_seq_num);
 141                                 r->first_time = true;
 142                                 wil_netif_rx_any(skb, ndev);
 143                                 goto out;
 144                         }
 145                         wil_err(wil,
 146                                 "Error: 1-st frame with wrong sequence 0x%03x, should be 0x%03x. Fixing...\n",
 147                                 seq, r->head_seq_num);
 148                         r->head_seq_num = seq;
 149                         r->ssn = seq;
 150                 }
 151         }
 152
 153         /* frame with out of date sequence number */
 154         if (seq_less(seq, r->head_seq_num)) {
 155                 r->ssn_last_drop = seq;
 156                 dev_kfree_skb(skb);
 157                 goto out;
 158         }
 159
 160         /*
 161          * If frame the sequence number exceeds our buffering window
 162          * size release some previous frames to make room for this one.
 163          */
 164         if (!seq_less(seq, r->head_seq_num + r->buf_size)) {
 165                 hseq = seq_inc(seq_sub(seq, r->buf_size));
 166                 /* release stored frames up to new head to stack */
 167                 wil_release_reorder_frames(wil, r, hseq);
 168         }
 169
 170         /* Now the new frame is always in the range of the reordering buffer */
 171
 172         index = reorder_index(r, seq);
 173
 174         /* check if we already stored this frame */
 175         if (r->reorder_buf[index]) {
 176                 dev_kfree_skb(skb);
 177                 goto out;
 178         }
 179
 180         /*
 181          * If the current MPDU is in the right order and nothing else
 182          * is stored we can process it directly, no need to buffer it.
 183          * If it is first but there's something stored, we may be able
 184          * to release frames after this one.
 185          */
 186         if (seq == r->head_seq_num && r->stored_mpdu_num == 0) {
 187                 r->head_seq_num = seq_inc(r->head_seq_num);
 188                 wil_netif_rx_any(skb, ndev);
 189                 goto out;
 190         }
 191
 192         /* put the frame in the reordering buffer */
 193         r->reorder_buf[index] = skb;
 194         r->reorder_time[index] = jiffies;
 195         r->stored_mpdu_num++;
 196         wil_reorder_release(wil, r);
 197
 198 out:
 199         spin_unlock(&sta->tid_rx_lock);
 200 }
 201
 202 struct wil_tid_ampdu_rx *wil_tid_ampdu_rx_alloc(struct wil6210_priv *wil,
 203                                                 int size, u16 ssn)
 204 {
 205         struct wil_tid_ampdu_rx *r = kzalloc(sizeof(*r), GFP_KERNEL);
 206
 207         if (!r)
 208                 return NULL;
 209
 210         r->reorder_buf =
 211                 kcalloc(size, sizeof(struct sk_buff *), GFP_KERNEL);
 212         r->reorder_time =
 213                 kcalloc(size, sizeof(unsigned long), GFP_KERNEL);
 214         if (!r->reorder_buf || !r->reorder_time) {
 215                 kfree(r->reorder_buf);
 216                 kfree(r->reorder_time);
 217                 kfree(r);
 218                 return NULL;
 219         }
 220
 221         r->ssn = ssn;
 222         r->head_seq_num = ssn;
 223         r->buf_size = size;
 224         r->stored_mpdu_num = 0;
 225         r->first_time = true;
 226         return r;
 227 }
 228
 229 void wil_tid_ampdu_rx_free(struct wil6210_priv *wil,
 230                            struct wil_tid_ampdu_rx *r)
 231 {
 232         if (!r)
 233                 return;
 234         wil_release_reorder_frames(wil, r, r->head_seq_num + r->buf_size);
 235         kfree(r->reorder_buf);
 236         kfree(r->reorder_time);
 237         kfree(r);
 238 }
 239
 240 /* ADDBA processing */
 241 static u16 wil_agg_size(struct wil6210_priv *wil, u16 req_agg_wsize)
 242 {
 243         u16 max_agg_size = min_t(u16, WIL_MAX_AGG_WSIZE, WIL_MAX_AMPDU_SIZE /
 244                                  (mtu_max + WIL_MAX_MPDU_OVERHEAD));
 245
 246         if (!req_agg_wsize)
 247                 return max_agg_size;
 248
 249         return min(max_agg_size, req_agg_wsize);
 250 }
 251
 252 /* Block Ack - Rx side (recipient */
 253 int wil_addba_rx_request(struct wil6210_priv *wil, u8 cidxtid,
 254                          u8 dialog_token, __le16 ba_param_set,
 255                          __le16 ba_timeout, __le16 ba_seq_ctrl)
 256 {
 257         struct wil_back_rx *req = kzalloc(sizeof(*req), GFP_KERNEL);
 258
 259         if (!req)
 260                 return -ENOMEM;
 261
 262         req->cidxtid = cidxtid;
 263         req->dialog_token = dialog_token;
 264         req->ba_param_set = le16_to_cpu(ba_param_set);
 265         req->ba_timeout = le16_to_cpu(ba_timeout);
 266         req->ba_seq_ctrl = le16_to_cpu(ba_seq_ctrl);
 267
 268         mutex_lock(&wil->back_rx_mutex);
 269         list_add_tail(&req->list, &wil->back_rx_pending);
 270         mutex_unlock(&wil->back_rx_mutex);
 271
 272         queue_work(wil->wq_service, &wil->back_rx_worker);
 273
 274         return 0;
 275 }
 276
 277 static void wil_back_rx_handle(struct wil6210_priv *wil,
 278                                struct wil_back_rx *req)
 279 __acquires(&sta->tid_rx_lock) __releases(&sta->tid_rx_lock)
 280 {
 281         struct wil_sta_info *sta;
 282         u8 cid, tid;
 283         u16 agg_wsize = 0;
 284         /* bit 0: A-MSDU supported
 285          * bit 1: policy (should be 0 for us)
 286          * bits 2..5: TID
 287          * bits 6..15: buffer size
 288          */
 289         u16 req_agg_wsize = WIL_GET_BITS(req->ba_param_set, 6, 15);
 290         bool agg_amsdu = !!(req->ba_param_set & BIT(0));
 291         int ba_policy = req->ba_param_set & BIT(1);
 292         u16 agg_timeout = req->ba_timeout;
 293         u16 status = WLAN_STATUS_SUCCESS;
 294         u16 ssn = req->ba_seq_ctrl >> 4;
 295         struct wil_tid_ampdu_rx *r;
 296         int rc;
 297
 298         might_sleep();
 299         parse_cidxtid(req->cidxtid, &cid, &tid);
 300
 301         /* sanity checks */
 302         if (cid >= WIL6210_MAX_CID) {
 303                 wil_err(wil, "BACK: invalid CID %d\n", cid);
 304                 return;
 305         }
 306
 307         sta = &wil->sta[cid];
 308         if (sta->status != wil_sta_connected) {
 309                 wil_err(wil, "BACK: CID %d not connected\n", cid);
 310                 return;
 311         }
 312
 313         wil_dbg_wmi(wil,
 314                     "ADDBA request for CID %d %pM TID %d size %d timeout %d AMSDU%s policy %d token %d SSN 0x%03x\n",
 315                     cid, sta->addr, tid, req_agg_wsize, req->ba_timeout,
 316                     agg_amsdu ? "+" : "-", !!ba_policy, req->dialog_token, ssn);
 317
 318         /* apply policies */
 319         if (ba_policy) {
 320                 wil_err(wil, "BACK requested unsupported ba_policy == 1\n");
 321                 status = WLAN_STATUS_INVALID_QOS_PARAM;
 322         }
 323         if (status == WLAN_STATUS_SUCCESS)
 324                 agg_wsize = wil_agg_size(wil, req_agg_wsize);
 325
 326         rc = wmi_addba_rx_resp(wil, cid, tid, req->dialog_token, status,
 327                                agg_amsdu, agg_wsize, agg_timeout);
 328         if (rc || (status != WLAN_STATUS_SUCCESS))
 329                 return;
 330
 331         /* apply */
 332         r = wil_tid_ampdu_rx_alloc(wil, agg_wsize, ssn);
 333         spin_lock_bh(&sta->tid_rx_lock);
 334         wil_tid_ampdu_rx_free(wil, sta->tid_rx[tid]);
 335         sta->tid_rx[tid] = r;
 336         spin_unlock_bh(&sta->tid_rx_lock);
 337 }
 338
 339 void wil_back_rx_flush(struct wil6210_priv *wil)
 340 {
 341         struct wil_back_rx *evt, *t;
 342
 343         wil_dbg_misc(wil, "%s()\n", __func__);
 344
 345         mutex_lock(&wil->back_rx_mutex);
 346
 347         list_for_each_entry_safe(evt, t, &wil->back_rx_pending, list) {
 348                 list_del(&evt->list);
 349                 kfree(evt);
 350         }
 351
 352         mutex_unlock(&wil->back_rx_mutex);
 353 }
 354
 355 /* Retrieve next ADDBA request from the pending list */
 356 static struct list_head *next_back_rx(struct wil6210_priv *wil)
 357 {
 358         struct list_head *ret = NULL;
 359
 360         mutex_lock(&wil->back_rx_mutex);
 361
 362         if (!list_empty(&wil->back_rx_pending)) {
 363                 ret = wil->back_rx_pending.next;
 364                 list_del(ret);
 365         }
 366
 367         mutex_unlock(&wil->back_rx_mutex);
 368
 369         return ret;
 370 }
 371
 372 void wil_back_rx_worker(struct work_struct *work)
 373 {
 374         struct wil6210_priv *wil = container_of(work, struct wil6210_priv,
 375                                                 back_rx_worker);
 376         struct wil_back_rx *evt;
 377         struct list_head *lh;
 378
 379         while ((lh = next_back_rx(wil)) != NULL) {
 380                 evt = list_entry(lh, struct wil_back_rx, list);
 381
 382                 wil_back_rx_handle(wil, evt);
 383                 kfree(evt);
 384         }
 385 }
 386
 387 /* BACK - Tx (originator) side */
 388 static void wil_back_tx_handle(struct wil6210_priv *wil,
 389                                struct wil_back_tx *req)
 390 {
 391         struct vring_tx_data *txdata = &wil->vring_tx_data[req->ringid];
 392         int rc;
 393
 394         if (txdata->addba_in_progress) {
 395                 wil_dbg_misc(wil, "ADDBA for vring[%d] already in progress\n",
 396                              req->ringid);
 397                 return;
 398         }
 399         if (txdata->agg_wsize) {
 400                 wil_dbg_misc(wil,
 401                              "ADDBA for vring[%d] already established wsize %d\n",
 402                              req->ringid, txdata->agg_wsize);
 403                 return;
 404         }
 405         txdata->addba_in_progress = true;
 406         rc = wmi_addba(wil, req->ringid, req->agg_wsize, req->agg_timeout);
 407         if (rc)
 408                 txdata->addba_in_progress = false;
 409 }
 410
 411 static struct list_head *next_back_tx(struct wil6210_priv *wil)
 412 {
 413         struct list_head *ret = NULL;
 414
 415         mutex_lock(&wil->back_tx_mutex);
 416
 417         if (!list_empty(&wil->back_tx_pending)) {
 418                 ret = wil->back_tx_pending.next;
 419                 list_del(ret);
 420         }
 421
 422         mutex_unlock(&wil->back_tx_mutex);
 423
 424         return ret;
 425 }
 426
 427 void wil_back_tx_worker(struct work_struct *work)
 428 {
 429         struct wil6210_priv *wil = container_of(work, struct wil6210_priv,
 430                                                  back_tx_worker);
 431         struct wil_back_tx *evt;
 432         struct list_head *lh;
 433
 434         while ((lh = next_back_tx(wil)) != NULL) {
 435                 evt = list_entry(lh, struct wil_back_tx, list);
 436
 437                 wil_back_tx_handle(wil, evt);
 438                 kfree(evt);
 439         }
 440 }
 441
 442 void wil_back_tx_flush(struct wil6210_priv *wil)
 443 {
 444         struct wil_back_tx *evt, *t;
 445
 446         wil_dbg_misc(wil, "%s()\n", __func__);
 447
 448         mutex_lock(&wil->back_tx_mutex);
 449
 450         list_for_each_entry_safe(evt, t, &wil->back_tx_pending, list) {
 451                 list_del(&evt->list);
 452                 kfree(evt);
 453         }
 454
 455         mutex_unlock(&wil->back_tx_mutex);
 456 }
 457
 458 int wil_addba_tx_request(struct wil6210_priv *wil, u8 ringid, u16 wsize)
 459 {
 460         struct wil_back_tx *req = kzalloc(sizeof(*req), GFP_KERNEL);
 461
 462         if (!req)
 463                 return -ENOMEM;
 464
 465         req->ringid = ringid;
 466         req->agg_wsize = wil_agg_size(wil, wsize);
 467         req->agg_timeout = 0;
 468
 469         mutex_lock(&wil->back_tx_mutex);
 470         list_add_tail(&req->list, &wil->back_tx_pending);
 471         mutex_unlock(&wil->back_tx_mutex);
 472
 473         queue_work(wil->wq_service, &wil->back_tx_worker);
 474
 475         return 0;
 476 }