drivers/net/wireless/rt2x00/rt2x00queue.c

   1 /*
   2         Copyright (C) 2004 - 2009 rt2x00 SourceForge Project
   3         <http://rt2x00.serialmonkey.com>
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the
  17         Free Software Foundation, Inc.,
  18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22         Module: rt2x00lib
  23         Abstract: rt2x00 queue specific routines.
  24  */
  25
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/dma-mapping.h>
  29
  30 #include "rt2x00.h"
  31 #include "rt2x00lib.h"
  32
  33 struct sk_buff *rt2x00queue_alloc_rxskb(struct rt2x00_dev *rt2x00dev,
  34                                         struct queue_entry *entry)
  35 {
  36         struct sk_buff *skb;
  37         struct skb_frame_desc *skbdesc;
  38         unsigned int frame_size;
  39         unsigned int head_size = 0;
  40         unsigned int tail_size = 0;
  41
  42         /*
  43          * The frame size includes descriptor size, because the
  44          * hardware directly receive the frame into the skbuffer.
  45          */
  46         frame_size = entry->queue->data_size + entry->queue->desc_size;
  47
  48         /*
  49          * The payload should be aligned to a 4-byte boundary,
  50          * this means we need at least 3 bytes for moving the frame
  51          * into the correct offset.
  52          */
  53         head_size = 4;
  54
  55         /*
  56          * For IV/EIV/ICV assembly we must make sure there is
  57          * at least 8 bytes bytes available in headroom for IV/EIV
  58          * and 8 bytes for ICV data as tailroon.
  59          */
  60         if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
  61                 head_size += 8;
  62                 tail_size += 8;
  63         }
  64
  65         /*
  66          * Allocate skbuffer.
  67          */
  68         skb = dev_alloc_skb(frame_size + head_size + tail_size);
  69         if (!skb)
  70                 return NULL;
  71
  72         /*
  73          * Make sure we not have a frame with the requested bytes
  74          * available in the head and tail.
  75          */
  76         skb_reserve(skb, head_size);
  77         skb_put(skb, frame_size);
  78
  79         /*
  80          * Populate skbdesc.
  81          */
  82         skbdesc = get_skb_frame_desc(skb);
  83         memset(skbdesc, 0, sizeof(*skbdesc));
  84         skbdesc->entry = entry;
  85
  86         if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) {
  87                 skbdesc->skb_dma = dma_map_single(rt2x00dev->dev,
  88                                                   skb->data,
  89                                                   skb->len,
  90                                                   DMA_FROM_DEVICE);
  91                 skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
  92         }
  93
  94         return skb;
  95 }
  96
  97 void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
  98 {
  99         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 100
 101         /*
 102          * If device has requested headroom, we should make sure that
 103          * is also mapped to the DMA so it can be used for transfering
 104          * additional descriptor information to the hardware.
 105          */
 106         skb_push(skb, rt2x00dev->hw->extra_tx_headroom);
 107
 108         skbdesc->skb_dma =
 109             dma_map_single(rt2x00dev->dev, skb->data, skb->len, DMA_TO_DEVICE);
 110
 111         /*
 112          * Restore data pointer to original location again.
 113          */
 114         skb_pull(skb, rt2x00dev->hw->extra_tx_headroom);
 115
 116         skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
 117 }
 118 EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
 119
 120 void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 121 {
 122         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 123
 124         if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
 125                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma, skb->len,
 126                                  DMA_FROM_DEVICE);
 127                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
 128         }
 129
 130         if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
 131                 /*
 132                  * Add headroom to the skb length, it has been removed
 133                  * by the driver, but it was actually mapped to DMA.
 134                  */
 135                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma,
 136                                  skb->len + rt2x00dev->hw->extra_tx_headroom,
 137                                  DMA_TO_DEVICE);
 138                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
 139         }
 140 }
 141
 142 void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 143 {
 144         if (!skb)
 145                 return;
 146
 147         rt2x00queue_unmap_skb(rt2x00dev, skb);
 148         dev_kfree_skb_any(skb);
 149 }
 150
 151 void rt2x00queue_payload_align(struct sk_buff *skb,
 152                                bool l2pad, unsigned int header_length)
 153 {
 154         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 155         unsigned int frame_length = skb->len;
 156         unsigned int align = ALIGN_SIZE(skb, header_length);
 157
 158         if (!align)
 159                 return;
 160
 161         if (l2pad) {
 162                 if (skbdesc->flags & SKBDESC_L2_PADDED) {
 163                         /* Remove L2 padding */
 164                         memmove(skb->data + align, skb->data, header_length);
 165                         skb_pull(skb, align);
 166                         skbdesc->flags &= ~SKBDESC_L2_PADDED;
 167                 } else {
 168                         /* Add L2 padding */
 169                         skb_push(skb, align);
 170                         memmove(skb->data, skb->data + align, header_length);
 171                         skbdesc->flags |= SKBDESC_L2_PADDED;
 172                 }
 173         } else {
 174                 /* Generic payload alignment to 4-byte boundary */
 175                 skb_push(skb, align);
 176                 memmove(skb->data, skb->data + align, frame_length);
 177         }
 178 }
 179
 180 static void rt2x00queue_create_tx_descriptor_seq(struct queue_entry *entry,
 181                                                  struct txentry_desc *txdesc)
 182 {
 183         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 184         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 185         struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
 186         unsigned long irqflags;
 187
 188         if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) ||
 189             unlikely(!tx_info->control.vif))
 190                 return;
 191
 192         /*
 193          * Hardware should insert sequence counter.
 194          * FIXME: We insert a software sequence counter first for
 195          * hardware that doesn't support hardware sequence counting.
 196          *
 197          * This is wrong because beacons are not getting sequence
 198          * numbers assigned properly.
 199          *
 200          * A secondary problem exists for drivers that cannot toggle
 201          * sequence counting per-frame, since those will override the
 202          * sequence counter given by mac80211.
 203          */
 204         spin_lock_irqsave(&intf->seqlock, irqflags);
 205
 206         if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
 207                 intf->seqno += 0x10;
 208         hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
 209         hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
 210
 211         spin_unlock_irqrestore(&intf->seqlock, irqflags);
 212
 213         __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
 214 }
 215
 216 static void rt2x00queue_create_tx_descriptor_plcp(struct queue_entry *entry,
 217                                                   struct txentry_desc *txdesc,
 218                                                   const struct rt2x00_rate *hwrate)
 219 {
 220         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 221         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 222         struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
 223         unsigned int data_length;
 224         unsigned int duration;
 225         unsigned int residual;
 226
 227         /* Data length + CRC + Crypto overhead (IV/EIV/ICV/MIC) */
 228         data_length = entry->skb->len + 4;
 229         data_length += rt2x00crypto_tx_overhead(rt2x00dev, entry->skb);
 230
 231         /*
 232          * PLCP setup
 233          * Length calculation depends on OFDM/CCK rate.
 234          */
 235         txdesc->signal = hwrate->plcp;
 236         txdesc->service = 0x04;
 237
 238         if (hwrate->flags & DEV_RATE_OFDM) {
 239                 txdesc->length_high = (data_length >> 6) & 0x3f;
 240                 txdesc->length_low = data_length & 0x3f;
 241         } else {
 242                 /*
 243                  * Convert length to microseconds.
 244                  */
 245                 residual = GET_DURATION_RES(data_length, hwrate->bitrate);
 246                 duration = GET_DURATION(data_length, hwrate->bitrate);
 247
 248                 if (residual != 0) {
 249                         duration++;
 250
 251                         /*
 252                          * Check if we need to set the Length Extension
 253                          */
 254                         if (hwrate->bitrate == 110 && residual <= 30)
 255                                 txdesc->service |= 0x80;
 256                 }
 257
 258                 txdesc->length_high = (duration >> 8) & 0xff;
 259                 txdesc->length_low = duration & 0xff;
 260
 261                 /*
 262                  * When preamble is enabled we should set the
 263                  * preamble bit for the signal.
 264                  */
 265                 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
 266                         txdesc->signal |= 0x08;
 267         }
 268 }
 269
 270 static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 271                                              struct txentry_desc *txdesc)
 272 {
 273         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 274         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 275         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 276         struct ieee80211_rate *rate =
 277             ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
 278         const struct rt2x00_rate *hwrate;
 279
 280         memset(txdesc, 0, sizeof(*txdesc));
 281
 282         /*
 283          * Initialize information from queue
 284          */
 285         txdesc->queue = entry->queue->qid;
 286         txdesc->cw_min = entry->queue->cw_min;
 287         txdesc->cw_max = entry->queue->cw_max;
 288         txdesc->aifs = entry->queue->aifs;
 289
 290         /*
 291          * Header and alignment information.
 292          */
 293         txdesc->header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
 294         txdesc->l2pad = ALIGN_SIZE(entry->skb, txdesc->header_length);
 295
 296         /*
 297          * Check whether this frame is to be acked.
 298          */
 299         if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
 300                 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
 301
 302         /*
 303          * Check if this is a RTS/CTS frame
 304          */
 305         if (ieee80211_is_rts(hdr->frame_control) ||
 306             ieee80211_is_cts(hdr->frame_control)) {
 307                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 308                 if (ieee80211_is_rts(hdr->frame_control))
 309                         __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
 310                 else
 311                         __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
 312                 if (tx_info->control.rts_cts_rate_idx >= 0)
 313                         rate =
 314                             ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
 315         }
 316
 317         /*
 318          * Determine retry information.
 319          */
 320         txdesc->retry_limit = tx_info->control.rates[0].count - 1;
 321         if (txdesc->retry_limit >= rt2x00dev->long_retry)
 322                 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
 323
 324         /*
 325          * Check if more fragments are pending
 326          */
 327         if (ieee80211_has_morefrags(hdr->frame_control) ||
 328             (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES)) {
 329                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 330                 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 331         }
 332
 333         /*
 334          * Beacons and probe responses require the tsf timestamp
 335          * to be inserted into the frame.
 336          */
 337         if (ieee80211_is_beacon(hdr->frame_control) ||
 338             ieee80211_is_probe_resp(hdr->frame_control))
 339                 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
 340
 341         /*
 342          * Determine with what IFS priority this frame should be send.
 343          * Set ifs to IFS_SIFS when the this is not the first fragment,
 344          * or this fragment came after RTS/CTS.
 345          */
 346         if ((tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) &&
 347             !test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
 348                 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
 349                 txdesc->ifs = IFS_BACKOFF;
 350         } else
 351                 txdesc->ifs = IFS_SIFS;
 352
 353         /*
 354          * Determine rate modulation.
 355          */
 356         hwrate = rt2x00_get_rate(rate->hw_value);
 357         txdesc->rate_mode = RATE_MODE_CCK;
 358         if (hwrate->flags & DEV_RATE_OFDM)
 359                 txdesc->rate_mode = RATE_MODE_OFDM;
 360
 361         /*
 362          * Apply TX descriptor handling by components
 363          */
 364         rt2x00crypto_create_tx_descriptor(entry, txdesc);
 365         rt2x00ht_create_tx_descriptor(entry, txdesc, hwrate);
 366         rt2x00queue_create_tx_descriptor_seq(entry, txdesc);
 367         rt2x00queue_create_tx_descriptor_plcp(entry, txdesc, hwrate);
 368 }
 369
 370 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
 371                                             struct txentry_desc *txdesc)
 372 {
 373         struct data_queue *queue = entry->queue;
 374         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 375
 376         rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
 377
 378         /*
 379          * All processing on the frame has been completed, this means
 380          * it is now ready to be dumped to userspace through debugfs.
 381          */
 382         rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
 383
 384         /*
 385          * Check if we need to kick the queue, there are however a few rules
 386          *      1) Don't kick beacon queue
 387          *      2) Don't kick unless this is the last in frame in a burst.
 388          *         When the burst flag is set, this frame is always followed
 389          *         by another frame which in some way are related to eachother.
 390          *         This is true for fragments, RTS or CTS-to-self frames.
 391          *      3) Rule 2 can be broken when the available entries
 392          *         in the queue are less then a certain threshold.
 393          */
 394         if (entry->queue->qid == QID_BEACON)
 395                 return;
 396
 397         if (rt2x00queue_threshold(queue) ||
 398             !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
 399                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
 400 }
 401
 402 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
 403 {
 404         struct ieee80211_tx_info *tx_info;
 405         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 406         struct txentry_desc txdesc;
 407         struct skb_frame_desc *skbdesc;
 408         u8 rate_idx, rate_flags;
 409
 410         if (unlikely(rt2x00queue_full(queue)))
 411                 return -ENOBUFS;
 412
 413         if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
 414                 ERROR(queue->rt2x00dev,
 415                       "Arrived at non-free entry in the non-full queue %d.\n"
 416                       "Please file bug report to %s.\n",
 417                       queue->qid, DRV_PROJECT);
 418                 return -EINVAL;
 419         }
 420
 421         /*
 422          * Copy all TX descriptor information into txdesc,
 423          * after that we are free to use the skb->cb array
 424          * for our information.
 425          */
 426         entry->skb = skb;
 427         rt2x00queue_create_tx_descriptor(entry, &txdesc);
 428
 429         /*
 430          * All information is retrieved from the skb->cb array,
 431          * now we should claim ownership of the driver part of that
 432          * array, preserving the bitrate index and flags.
 433          */
 434         tx_info = IEEE80211_SKB_CB(skb);
 435         rate_idx = tx_info->control.rates[0].idx;
 436         rate_flags = tx_info->control.rates[0].flags;
 437         skbdesc = get_skb_frame_desc(skb);
 438         memset(skbdesc, 0, sizeof(*skbdesc));
 439         skbdesc->entry = entry;
 440         skbdesc->tx_rate_idx = rate_idx;
 441         skbdesc->tx_rate_flags = rate_flags;
 442
 443         /*
 444          * When hardware encryption is supported, and this frame
 445          * is to be encrypted, we should strip the IV/EIV data from
 446          * the frame so we can provide it to the driver seperately.
 447          */
 448         if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
 449             !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
 450                 if (test_bit(DRIVER_REQUIRE_COPY_IV, &queue->rt2x00dev->flags))
 451                         rt2x00crypto_tx_copy_iv(skb, &txdesc);
 452                 else
 453                         rt2x00crypto_tx_remove_iv(skb, &txdesc);
 454         }
 455
 456         /*
 457          * When DMA allocation is required we should guarentee to the
 458          * driver that the DMA is aligned to a 4-byte boundary.
 459          * Aligning the header to this boundary can be done by calling
 460          * rt2x00queue_payload_align with the header length of 0.
 461          * However some drivers require L2 padding to pad the payload
 462          * rather then the header. This could be a requirement for
 463          * PCI and USB devices, while header alignment only is valid
 464          * for PCI devices.
 465          */
 466         if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
 467                 rt2x00queue_payload_align(entry->skb, true,
 468                                           txdesc.header_length);
 469         else if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 470                 rt2x00queue_payload_align(entry->skb, false, 0);
 471
 472         /*
 473          * It could be possible that the queue was corrupted and this
 474          * call failed. Since we always return NETDEV_TX_OK to mac80211,
 475          * this frame will simply be dropped.
 476          */
 477         if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
 478                 clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 479                 entry->skb = NULL;
 480                 return -EIO;
 481         }
 482
 483         if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 484                 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
 485
 486         set_bit(ENTRY_DATA_PENDING, &entry->flags);
 487
 488         rt2x00queue_index_inc(queue, Q_INDEX);
 489         rt2x00queue_write_tx_descriptor(entry, &txdesc);
 490
 491         return 0;
 492 }
 493
 494 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 495                               struct ieee80211_vif *vif,
 496                               const bool enable_beacon)
 497 {
 498         struct rt2x00_intf *intf = vif_to_intf(vif);
 499         struct skb_frame_desc *skbdesc;
 500         struct txentry_desc txdesc;
 501         __le32 desc[16];
 502
 503         if (unlikely(!intf->beacon))
 504                 return -ENOBUFS;
 505
 506         if (!enable_beacon) {
 507                 rt2x00dev->ops->lib->kill_tx_queue(rt2x00dev, QID_BEACON);
 508                 return 0;
 509         }
 510
 511         intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
 512         if (!intf->beacon->skb)
 513                 return -ENOMEM;
 514
 515         /*
 516          * Copy all TX descriptor information into txdesc,
 517          * after that we are free to use the skb->cb array
 518          * for our information.
 519          */
 520         rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
 521
 522         /*
 523          * For the descriptor we use a local array from where the
 524          * driver can move it to the correct location required for
 525          * the hardware.
 526          */
 527         memset(desc, 0, sizeof(desc));
 528
 529         /*
 530          * Fill in skb descriptor
 531          */
 532         skbdesc = get_skb_frame_desc(intf->beacon->skb);
 533         memset(skbdesc, 0, sizeof(*skbdesc));
 534         skbdesc->desc = desc;
 535         skbdesc->desc_len = intf->beacon->queue->desc_size;
 536         skbdesc->entry = intf->beacon;
 537
 538         /*
 539          * Write TX descriptor into reserved room in front of the beacon.
 540          */
 541         rt2x00queue_write_tx_descriptor(intf->beacon, &txdesc);
 542
 543         /*
 544          * Send beacon to hardware.
 545          * Also enable beacon generation, which might have been disabled
 546          * by the driver during the config_beacon() callback function.
 547          */
 548         rt2x00dev->ops->lib->write_beacon(intf->beacon);
 549         rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
 550
 551         return 0;
 552 }
 553
 554 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
 555                                          const enum data_queue_qid queue)
 556 {
 557         int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 558
 559         if (queue == QID_RX)
 560                 return rt2x00dev->rx;
 561
 562         if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
 563                 return &rt2x00dev->tx[queue];
 564
 565         if (!rt2x00dev->bcn)
 566                 return NULL;
 567
 568         if (queue == QID_BEACON)
 569                 return &rt2x00dev->bcn[0];
 570         else if (queue == QID_ATIM && atim)
 571                 return &rt2x00dev->bcn[1];
 572
 573         return NULL;
 574 }
 575 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
 576
 577 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
 578                                           enum queue_index index)
 579 {
 580         struct queue_entry *entry;
 581         unsigned long irqflags;
 582
 583         if (unlikely(index >= Q_INDEX_MAX)) {
 584                 ERROR(queue->rt2x00dev,
 585                       "Entry requested from invalid index type (%d)\n", index);
 586                 return NULL;
 587         }
 588
 589         spin_lock_irqsave(&queue->lock, irqflags);
 590
 591         entry = &queue->entries[queue->index[index]];
 592
 593         spin_unlock_irqrestore(&queue->lock, irqflags);
 594
 595         return entry;
 596 }
 597 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
 598
 599 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 600 {
 601         unsigned long irqflags;
 602
 603         if (unlikely(index >= Q_INDEX_MAX)) {
 604                 ERROR(queue->rt2x00dev,
 605                       "Index change on invalid index type (%d)\n", index);
 606                 return;
 607         }
 608
 609         spin_lock_irqsave(&queue->lock, irqflags);
 610
 611         queue->index[index]++;
 612         if (queue->index[index] >= queue->limit)
 613                 queue->index[index] = 0;
 614
 615         if (index == Q_INDEX) {
 616                 queue->length++;
 617         } else if (index == Q_INDEX_DONE) {
 618                 queue->length--;
 619                 queue->count++;
 620         }
 621
 622         spin_unlock_irqrestore(&queue->lock, irqflags);
 623 }
 624
 625 static void rt2x00queue_reset(struct data_queue *queue)
 626 {
 627         unsigned long irqflags;
 628
 629         spin_lock_irqsave(&queue->lock, irqflags);
 630
 631         queue->count = 0;
 632         queue->length = 0;
 633         memset(queue->index, 0, sizeof(queue->index));
 634
 635         spin_unlock_irqrestore(&queue->lock, irqflags);
 636 }
 637
 638 void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev)
 639 {
 640         struct data_queue *queue;
 641
 642         txall_queue_for_each(rt2x00dev, queue)
 643                 rt2x00dev->ops->lib->kill_tx_queue(rt2x00dev, queue->qid);
 644 }
 645
 646 void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
 647 {
 648         struct data_queue *queue;
 649         unsigned int i;
 650
 651         queue_for_each(rt2x00dev, queue) {
 652                 rt2x00queue_reset(queue);
 653
 654                 for (i = 0; i < queue->limit; i++) {
 655                         queue->entries[i].flags = 0;
 656
 657                         rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
 658                 }
 659         }
 660 }
 661
 662 static int rt2x00queue_alloc_entries(struct data_queue *queue,
 663                                      const struct data_queue_desc *qdesc)
 664 {
 665         struct queue_entry *entries;
 666         unsigned int entry_size;
 667         unsigned int i;
 668
 669         rt2x00queue_reset(queue);
 670
 671         queue->limit = qdesc->entry_num;
 672         queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
 673         queue->data_size = qdesc->data_size;
 674         queue->desc_size = qdesc->desc_size;
 675
 676         /*
 677          * Allocate all queue entries.
 678          */
 679         entry_size = sizeof(*entries) + qdesc->priv_size;
 680         entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
 681         if (!entries)
 682                 return -ENOMEM;
 683
 684 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
 685         ( ((char *)(__base)) + ((__limit) * (__esize)) + \
 686             ((__index) * (__psize)) )
 687
 688         for (i = 0; i < queue->limit; i++) {
 689                 entries[i].flags = 0;
 690                 entries[i].queue = queue;
 691                 entries[i].skb = NULL;
 692                 entries[i].entry_idx = i;
 693                 entries[i].priv_data =
 694                     QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
 695                                             sizeof(*entries), qdesc->priv_size);
 696         }
 697
 698 #undef QUEUE_ENTRY_PRIV_OFFSET
 699
 700         queue->entries = entries;
 701
 702         return 0;
 703 }
 704
 705 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
 706                                   struct data_queue *queue)
 707 {
 708         unsigned int i;
 709
 710         if (!queue->entries)
 711                 return;
 712
 713         for (i = 0; i < queue->limit; i++) {
 714                 if (queue->entries[i].skb)
 715                         rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
 716         }
 717 }
 718
 719 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
 720                                     struct data_queue *queue)
 721 {
 722         unsigned int i;
 723         struct sk_buff *skb;
 724
 725         for (i = 0; i < queue->limit; i++) {
 726                 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
 727                 if (!skb)
 728                         return -ENOMEM;
 729                 queue->entries[i].skb = skb;
 730         }
 731
 732         return 0;
 733 }
 734
 735 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
 736 {
 737         struct data_queue *queue;
 738         int status;
 739
 740         status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
 741         if (status)
 742                 goto exit;
 743
 744         tx_queue_for_each(rt2x00dev, queue) {
 745                 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
 746                 if (status)
 747                         goto exit;
 748         }
 749
 750         status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
 751         if (status)
 752                 goto exit;
 753
 754         if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
 755                 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
 756                                                    rt2x00dev->ops->atim);
 757                 if (status)
 758                         goto exit;
 759         }
 760
 761         status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
 762         if (status)
 763                 goto exit;
 764
 765         return 0;
 766
 767 exit:
 768         ERROR(rt2x00dev, "Queue entries allocation failed.\n");
 769
 770         rt2x00queue_uninitialize(rt2x00dev);
 771
 772         return status;
 773 }
 774
 775 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
 776 {
 777         struct data_queue *queue;
 778
 779         rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
 780
 781         queue_for_each(rt2x00dev, queue) {
 782                 kfree(queue->entries);
 783                 queue->entries = NULL;
 784         }
 785 }
 786
 787 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
 788                              struct data_queue *queue, enum data_queue_qid qid)
 789 {
 790         spin_lock_init(&queue->lock);
 791
 792         queue->rt2x00dev = rt2x00dev;
 793         queue->qid = qid;
 794         queue->txop = 0;
 795         queue->aifs = 2;
 796         queue->cw_min = 5;
 797         queue->cw_max = 10;
 798 }
 799
 800 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
 801 {
 802         struct data_queue *queue;
 803         enum data_queue_qid qid;
 804         unsigned int req_atim =
 805             !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 806
 807         /*
 808          * We need the following queues:
 809          * RX: 1
 810          * TX: ops->tx_queues
 811          * Beacon: 1
 812          * Atim: 1 (if required)
 813          */
 814         rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
 815
 816         queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
 817         if (!queue) {
 818                 ERROR(rt2x00dev, "Queue allocation failed.\n");
 819                 return -ENOMEM;
 820         }
 821
 822         /*
 823          * Initialize pointers
 824          */
 825         rt2x00dev->rx = queue;
 826         rt2x00dev->tx = &queue[1];
 827         rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
 828
 829         /*
 830          * Initialize queue parameters.
 831          * RX: qid = QID_RX
 832          * TX: qid = QID_AC_BE + index
 833          * TX: cw_min: 2^5 = 32.
 834          * TX: cw_max: 2^10 = 1024.
 835          * BCN: qid = QID_BEACON
 836          * ATIM: qid = QID_ATIM
 837          */
 838         rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
 839
 840         qid = QID_AC_BE;
 841         tx_queue_for_each(rt2x00dev, queue)
 842                 rt2x00queue_init(rt2x00dev, queue, qid++);
 843
 844         rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
 845         if (req_atim)
 846                 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
 847
 848         return 0;
 849 }
 850
 851 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
 852 {
 853         kfree(rt2x00dev->rx);
 854         rt2x00dev->rx = NULL;
 855         rt2x00dev->tx = NULL;
 856         rt2x00dev->bcn = NULL;
 857 }