drivers/net/wireless/rt2x00/rt2x00queue.c

   1 /*
   2         Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
   3         Copyright (C) 2004 - 2009 Gertjan van Wingerde <gwingerde@gmail.com>
   4         <http://rt2x00.serialmonkey.com>
   5
   6         This program is free software; you can redistribute it and/or modify
   7         it under the terms of the GNU General Public License as published by
   8         the Free Software Foundation; either version 2 of the License, or
   9         (at your option) any later version.
  10
  11         This program is distributed in the hope that it will be useful,
  12         but WITHOUT ANY WARRANTY; without even the implied warranty of
  13         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14         GNU General Public License for more details.
  15
  16         You should have received a copy of the GNU General Public License
  17         along with this program; if not, write to the
  18         Free Software Foundation, Inc.,
  19         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 /*
  23         Module: rt2x00lib
  24         Abstract: rt2x00 queue specific routines.
  25  */
  26
  27 #include <linux/slab.h>
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/dma-mapping.h>
  31
  32 #include "rt2x00.h"
  33 #include "rt2x00lib.h"
  34
  35 struct sk_buff *rt2x00queue_alloc_rxskb(struct rt2x00_dev *rt2x00dev,
  36                                         struct queue_entry *entry)
  37 {
  38         struct sk_buff *skb;
  39         struct skb_frame_desc *skbdesc;
  40         unsigned int frame_size;
  41         unsigned int head_size = 0;
  42         unsigned int tail_size = 0;
  43
  44         /*
  45          * The frame size includes descriptor size, because the
  46          * hardware directly receive the frame into the skbuffer.
  47          */
  48         frame_size = entry->queue->data_size + entry->queue->desc_size;
  49
  50         /*
  51          * The payload should be aligned to a 4-byte boundary,
  52          * this means we need at least 3 bytes for moving the frame
  53          * into the correct offset.
  54          */
  55         head_size = 4;
  56
  57         /*
  58          * For IV/EIV/ICV assembly we must make sure there is
  59          * at least 8 bytes bytes available in headroom for IV/EIV
  60          * and 8 bytes for ICV data as tailroon.
  61          */
  62         if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
  63                 head_size += 8;
  64                 tail_size += 8;
  65         }
  66
  67         /*
  68          * Allocate skbuffer.
  69          */
  70         skb = dev_alloc_skb(frame_size + head_size + tail_size);
  71         if (!skb)
  72                 return NULL;
  73
  74         /*
  75          * Make sure we not have a frame with the requested bytes
  76          * available in the head and tail.
  77          */
  78         skb_reserve(skb, head_size);
  79         skb_put(skb, frame_size);
  80
  81         /*
  82          * Populate skbdesc.
  83          */
  84         skbdesc = get_skb_frame_desc(skb);
  85         memset(skbdesc, 0, sizeof(*skbdesc));
  86         skbdesc->entry = entry;
  87
  88         if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) {
  89                 skbdesc->skb_dma = dma_map_single(rt2x00dev->dev,
  90                                                   skb->data,
  91                                                   skb->len,
  92                                                   DMA_FROM_DEVICE);
  93                 skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
  94         }
  95
  96         return skb;
  97 }
  98
  99 void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 100 {
 101         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 102
 103         /*
 104          * If device has requested headroom, we should make sure that
 105          * is also mapped to the DMA so it can be used for transfering
 106          * additional descriptor information to the hardware.
 107          */
 108         skb_push(skb, rt2x00dev->ops->extra_tx_headroom);
 109
 110         skbdesc->skb_dma =
 111             dma_map_single(rt2x00dev->dev, skb->data, skb->len, DMA_TO_DEVICE);
 112
 113         /*
 114          * Restore data pointer to original location again.
 115          */
 116         skb_pull(skb, rt2x00dev->ops->extra_tx_headroom);
 117
 118         skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
 119 }
 120 EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
 121
 122 void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 123 {
 124         struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
 125
 126         if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
 127                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma, skb->len,
 128                                  DMA_FROM_DEVICE);
 129                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
 130         }
 131
 132         if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
 133                 /*
 134                  * Add headroom to the skb length, it has been removed
 135                  * by the driver, but it was actually mapped to DMA.
 136                  */
 137                 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma,
 138                                  skb->len + rt2x00dev->ops->extra_tx_headroom,
 139                                  DMA_TO_DEVICE);
 140                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
 141         }
 142 }
 143
 144 void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
 145 {
 146         if (!skb)
 147                 return;
 148
 149         rt2x00queue_unmap_skb(rt2x00dev, skb);
 150         dev_kfree_skb_any(skb);
 151 }
 152
 153 void rt2x00queue_align_frame(struct sk_buff *skb)
 154 {
 155         unsigned int frame_length = skb->len;
 156         unsigned int align = ALIGN_SIZE(skb, 0);
 157
 158         if (!align)
 159                 return;
 160
 161         skb_push(skb, align);
 162         memmove(skb->data, skb->data + align, frame_length);
 163         skb_trim(skb, frame_length);
 164 }
 165
 166 void rt2x00queue_align_payload(struct sk_buff *skb, unsigned int header_length)
 167 {
 168         unsigned int frame_length = skb->len;
 169         unsigned int align = ALIGN_SIZE(skb, header_length);
 170
 171         if (!align)
 172                 return;
 173
 174         skb_push(skb, align);
 175         memmove(skb->data, skb->data + align, frame_length);
 176         skb_trim(skb, frame_length);
 177 }
 178
 179 void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length)
 180 {
 181         unsigned int payload_length = skb->len - header_length;
 182         unsigned int header_align = ALIGN_SIZE(skb, 0);
 183         unsigned int payload_align = ALIGN_SIZE(skb, header_length);
 184         unsigned int l2pad = payload_length ? L2PAD_SIZE(header_length) : 0;
 185
 186         /*
 187          * Adjust the header alignment if the payload needs to be moved more
 188          * than the header.
 189          */
 190         if (payload_align > header_align)
 191                 header_align += 4;
 192
 193         /* There is nothing to do if no alignment is needed */
 194         if (!header_align)
 195                 return;
 196
 197         /* Reserve the amount of space needed in front of the frame */
 198         skb_push(skb, header_align);
 199
 200         /*
 201          * Move the header.
 202          */
 203         memmove(skb->data, skb->data + header_align, header_length);
 204
 205         /* Move the payload, if present and if required */
 206         if (payload_length && payload_align)
 207                 memmove(skb->data + header_length + l2pad,
 208                         skb->data + header_length + l2pad + payload_align,
 209                         payload_length);
 210
 211         /* Trim the skb to the correct size */
 212         skb_trim(skb, header_length + l2pad + payload_length);
 213 }
 214
 215 void rt2x00queue_remove_l2pad(struct sk_buff *skb, unsigned int header_length)
 216 {
 217         unsigned int l2pad = L2PAD_SIZE(header_length);
 218
 219         if (!l2pad)
 220                 return;
 221
 222         memmove(skb->data + l2pad, skb->data, header_length);
 223         skb_pull(skb, l2pad);
 224 }
 225
 226 static void rt2x00queue_create_tx_descriptor_seq(struct queue_entry *entry,
 227                                                  struct txentry_desc *txdesc)
 228 {
 229         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 230         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 231         struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
 232         unsigned long irqflags;
 233
 234         if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) ||
 235             unlikely(!tx_info->control.vif))
 236                 return;
 237
 238         /*
 239          * Hardware should insert sequence counter.
 240          * FIXME: We insert a software sequence counter first for
 241          * hardware that doesn't support hardware sequence counting.
 242          *
 243          * This is wrong because beacons are not getting sequence
 244          * numbers assigned properly.
 245          *
 246          * A secondary problem exists for drivers that cannot toggle
 247          * sequence counting per-frame, since those will override the
 248          * sequence counter given by mac80211.
 249          */
 250         spin_lock_irqsave(&intf->seqlock, irqflags);
 251
 252         if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
 253                 intf->seqno += 0x10;
 254         hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
 255         hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
 256
 257         spin_unlock_irqrestore(&intf->seqlock, irqflags);
 258
 259         __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
 260 }
 261
 262 static void rt2x00queue_create_tx_descriptor_plcp(struct queue_entry *entry,
 263                                                   struct txentry_desc *txdesc,
 264                                                   const struct rt2x00_rate *hwrate)
 265 {
 266         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 267         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 268         struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
 269         unsigned int data_length;
 270         unsigned int duration;
 271         unsigned int residual;
 272
 273         /* Data length + CRC + Crypto overhead (IV/EIV/ICV/MIC) */
 274         data_length = entry->skb->len + 4;
 275         data_length += rt2x00crypto_tx_overhead(rt2x00dev, entry->skb);
 276
 277         /*
 278          * PLCP setup
 279          * Length calculation depends on OFDM/CCK rate.
 280          */
 281         txdesc->signal = hwrate->plcp;
 282         txdesc->service = 0x04;
 283
 284         if (hwrate->flags & DEV_RATE_OFDM) {
 285                 txdesc->length_high = (data_length >> 6) & 0x3f;
 286                 txdesc->length_low = data_length & 0x3f;
 287         } else {
 288                 /*
 289                  * Convert length to microseconds.
 290                  */
 291                 residual = GET_DURATION_RES(data_length, hwrate->bitrate);
 292                 duration = GET_DURATION(data_length, hwrate->bitrate);
 293
 294                 if (residual != 0) {
 295                         duration++;
 296
 297                         /*
 298                          * Check if we need to set the Length Extension
 299                          */
 300                         if (hwrate->bitrate == 110 && residual <= 30)
 301                                 txdesc->service |= 0x80;
 302                 }
 303
 304                 txdesc->length_high = (duration >> 8) & 0xff;
 305                 txdesc->length_low = duration & 0xff;
 306
 307                 /*
 308                  * When preamble is enabled we should set the
 309                  * preamble bit for the signal.
 310                  */
 311                 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
 312                         txdesc->signal |= 0x08;
 313         }
 314 }
 315
 316 static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 317                                              struct txentry_desc *txdesc)
 318 {
 319         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 320         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 321         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 322         struct ieee80211_rate *rate =
 323             ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
 324         const struct rt2x00_rate *hwrate;
 325
 326         memset(txdesc, 0, sizeof(*txdesc));
 327
 328         /*
 329          * Initialize information from queue
 330          */
 331         txdesc->queue = entry->queue->qid;
 332         txdesc->cw_min = entry->queue->cw_min;
 333         txdesc->cw_max = entry->queue->cw_max;
 334         txdesc->aifs = entry->queue->aifs;
 335
 336         /*
 337          * Header and alignment information.
 338          */
 339         txdesc->header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
 340         if (test_bit(DRIVER_REQUIRE_L2PAD, &rt2x00dev->flags) &&
 341             (entry->skb->len > txdesc->header_length))
 342                 txdesc->l2pad = L2PAD_SIZE(txdesc->header_length);
 343
 344         /*
 345          * Check whether this frame is to be acked.
 346          */
 347         if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
 348                 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
 349
 350         /*
 351          * Check if this is a RTS/CTS frame
 352          */
 353         if (ieee80211_is_rts(hdr->frame_control) ||
 354             ieee80211_is_cts(hdr->frame_control)) {
 355                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 356                 if (ieee80211_is_rts(hdr->frame_control))
 357                         __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
 358                 else
 359                         __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
 360                 if (tx_info->control.rts_cts_rate_idx >= 0)
 361                         rate =
 362                             ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
 363         }
 364
 365         /*
 366          * Determine retry information.
 367          */
 368         txdesc->retry_limit = tx_info->control.rates[0].count - 1;
 369         if (txdesc->retry_limit >= rt2x00dev->long_retry)
 370                 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
 371
 372         /*
 373          * Check if more fragments are pending
 374          */
 375         if (ieee80211_has_morefrags(hdr->frame_control) ||
 376             (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES)) {
 377                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 378                 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 379         }
 380
 381         /*
 382          * Beacons and probe responses require the tsf timestamp
 383          * to be inserted into the frame, except for a frame that has been injected
 384          * through a monitor interface. This latter is needed for testing a
 385          * monitor interface.
 386          */
 387         if ((ieee80211_is_beacon(hdr->frame_control) ||
 388             ieee80211_is_probe_resp(hdr->frame_control)) &&
 389             (!(tx_info->flags & IEEE80211_TX_CTL_INJECTED)))
 390                 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
 391
 392         /*
 393          * Determine with what IFS priority this frame should be send.
 394          * Set ifs to IFS_SIFS when the this is not the first fragment,
 395          * or this fragment came after RTS/CTS.
 396          */
 397         if ((tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) &&
 398             !test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
 399                 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
 400                 txdesc->ifs = IFS_BACKOFF;
 401         } else
 402                 txdesc->ifs = IFS_SIFS;
 403
 404         /*
 405          * Determine rate modulation.
 406          */
 407         hwrate = rt2x00_get_rate(rate->hw_value);
 408         txdesc->rate_mode = RATE_MODE_CCK;
 409         if (hwrate->flags & DEV_RATE_OFDM)
 410                 txdesc->rate_mode = RATE_MODE_OFDM;
 411
 412         /*
 413          * Apply TX descriptor handling by components
 414          */
 415         rt2x00crypto_create_tx_descriptor(entry, txdesc);
 416         rt2x00ht_create_tx_descriptor(entry, txdesc, hwrate);
 417         rt2x00queue_create_tx_descriptor_seq(entry, txdesc);
 418         rt2x00queue_create_tx_descriptor_plcp(entry, txdesc, hwrate);
 419 }
 420
 421 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
 422                                             struct txentry_desc *txdesc)
 423 {
 424         struct data_queue *queue = entry->queue;
 425         struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
 426
 427         rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
 428
 429         /*
 430          * All processing on the frame has been completed, this means
 431          * it is now ready to be dumped to userspace through debugfs.
 432          */
 433         rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
 434
 435         /*
 436          * Check if we need to kick the queue, there are however a few rules
 437          *      1) Don't kick beacon queue
 438          *      2) Don't kick unless this is the last in frame in a burst.
 439          *         When the burst flag is set, this frame is always followed
 440          *         by another frame which in some way are related to eachother.
 441          *         This is true for fragments, RTS or CTS-to-self frames.
 442          *      3) Rule 2 can be broken when the available entries
 443          *         in the queue are less then a certain threshold.
 444          */
 445         if (entry->queue->qid == QID_BEACON)
 446                 return;
 447
 448         if (rt2x00queue_threshold(queue) ||
 449             !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
 450                 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
 451 }
 452
 453 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb,
 454                                bool local)
 455 {
 456         struct ieee80211_tx_info *tx_info;
 457         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 458         struct txentry_desc txdesc;
 459         struct skb_frame_desc *skbdesc;
 460         u8 rate_idx, rate_flags;
 461
 462         if (unlikely(rt2x00queue_full(queue)))
 463                 return -ENOBUFS;
 464
 465         if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
 466                 ERROR(queue->rt2x00dev,
 467                       "Arrived at non-free entry in the non-full queue %d.\n"
 468                       "Please file bug report to %s.\n",
 469                       queue->qid, DRV_PROJECT);
 470                 return -EINVAL;
 471         }
 472
 473         /*
 474          * Copy all TX descriptor information into txdesc,
 475          * after that we are free to use the skb->cb array
 476          * for our information.
 477          */
 478         entry->skb = skb;
 479         rt2x00queue_create_tx_descriptor(entry, &txdesc);
 480
 481         /*
 482          * All information is retrieved from the skb->cb array,
 483          * now we should claim ownership of the driver part of that
 484          * array, preserving the bitrate index and flags.
 485          */
 486         tx_info = IEEE80211_SKB_CB(skb);
 487         rate_idx = tx_info->control.rates[0].idx;
 488         rate_flags = tx_info->control.rates[0].flags;
 489         skbdesc = get_skb_frame_desc(skb);
 490         memset(skbdesc, 0, sizeof(*skbdesc));
 491         skbdesc->entry = entry;
 492         skbdesc->tx_rate_idx = rate_idx;
 493         skbdesc->tx_rate_flags = rate_flags;
 494
 495         if (local)
 496                 skbdesc->flags |= SKBDESC_NOT_MAC80211;
 497
 498         /*
 499          * When hardware encryption is supported, and this frame
 500          * is to be encrypted, we should strip the IV/EIV data from
 501          * the frame so we can provide it to the driver separately.
 502          */
 503         if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
 504             !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
 505                 if (test_bit(DRIVER_REQUIRE_COPY_IV, &queue->rt2x00dev->flags))
 506                         rt2x00crypto_tx_copy_iv(skb, &txdesc);
 507                 else
 508                         rt2x00crypto_tx_remove_iv(skb, &txdesc);
 509         }
 510
 511         /*
 512          * When DMA allocation is required we should guarentee to the
 513          * driver that the DMA is aligned to a 4-byte boundary.
 514          * However some drivers require L2 padding to pad the payload
 515          * rather then the header. This could be a requirement for
 516          * PCI and USB devices, while header alignment only is valid
 517          * for PCI devices.
 518          */
 519         if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
 520                 rt2x00queue_insert_l2pad(entry->skb, txdesc.header_length);
 521         else if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 522                 rt2x00queue_align_frame(entry->skb);
 523
 524         /*
 525          * It could be possible that the queue was corrupted and this
 526          * call failed. Since we always return NETDEV_TX_OK to mac80211,
 527          * this frame will simply be dropped.
 528          */
 529         if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
 530                 clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 531                 entry->skb = NULL;
 532                 return -EIO;
 533         }
 534
 535         if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 536                 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
 537
 538         set_bit(ENTRY_DATA_PENDING, &entry->flags);
 539
 540         rt2x00queue_index_inc(queue, Q_INDEX);
 541         rt2x00queue_write_tx_descriptor(entry, &txdesc);
 542
 543         return 0;
 544 }
 545
 546 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 547                               struct ieee80211_vif *vif,
 548                               const bool enable_beacon)
 549 {
 550         struct rt2x00_intf *intf = vif_to_intf(vif);
 551         struct skb_frame_desc *skbdesc;
 552         struct txentry_desc txdesc;
 553         __le32 desc[16];
 554
 555         if (unlikely(!intf->beacon))
 556                 return -ENOBUFS;
 557
 558         mutex_lock(&intf->beacon_skb_mutex);
 559
 560         /*
 561          * Clean up the beacon skb.
 562          */
 563         rt2x00queue_free_skb(rt2x00dev, intf->beacon->skb);
 564         intf->beacon->skb = NULL;
 565
 566         if (!enable_beacon) {
 567                 rt2x00dev->ops->lib->kill_tx_queue(rt2x00dev, QID_BEACON);
 568                 mutex_unlock(&intf->beacon_skb_mutex);
 569                 return 0;
 570         }
 571
 572         intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
 573         if (!intf->beacon->skb) {
 574                 mutex_unlock(&intf->beacon_skb_mutex);
 575                 return -ENOMEM;
 576         }
 577
 578         /*
 579          * Copy all TX descriptor information into txdesc,
 580          * after that we are free to use the skb->cb array
 581          * for our information.
 582          */
 583         rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
 584
 585         /*
 586          * For the descriptor we use a local array from where the
 587          * driver can move it to the correct location required for
 588          * the hardware.
 589          */
 590         memset(desc, 0, sizeof(desc));
 591
 592         /*
 593          * Fill in skb descriptor
 594          */
 595         skbdesc = get_skb_frame_desc(intf->beacon->skb);
 596         memset(skbdesc, 0, sizeof(*skbdesc));
 597         skbdesc->desc = desc;
 598         skbdesc->desc_len = intf->beacon->queue->desc_size;
 599         skbdesc->entry = intf->beacon;
 600
 601         /*
 602          * Write TX descriptor into reserved room in front of the beacon.
 603          */
 604         rt2x00queue_write_tx_descriptor(intf->beacon, &txdesc);
 605
 606         /*
 607          * Send beacon to hardware.
 608          * Also enable beacon generation, which might have been disabled
 609          * by the driver during the config_beacon() callback function.
 610          */
 611         rt2x00dev->ops->lib->write_beacon(intf->beacon);
 612         rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
 613
 614         mutex_unlock(&intf->beacon_skb_mutex);
 615
 616         return 0;
 617 }
 618
 619 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
 620                                          const enum data_queue_qid queue)
 621 {
 622         int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 623
 624         if (queue == QID_RX)
 625                 return rt2x00dev->rx;
 626
 627         if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
 628                 return &rt2x00dev->tx[queue];
 629
 630         if (!rt2x00dev->bcn)
 631                 return NULL;
 632
 633         if (queue == QID_BEACON)
 634                 return &rt2x00dev->bcn[0];
 635         else if (queue == QID_ATIM && atim)
 636                 return &rt2x00dev->bcn[1];
 637
 638         return NULL;
 639 }
 640 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
 641
 642 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
 643                                           enum queue_index index)
 644 {
 645         struct queue_entry *entry;
 646         unsigned long irqflags;
 647
 648         if (unlikely(index >= Q_INDEX_MAX)) {
 649                 ERROR(queue->rt2x00dev,
 650                       "Entry requested from invalid index type (%d)\n", index);
 651                 return NULL;
 652         }
 653
 654         spin_lock_irqsave(&queue->lock, irqflags);
 655
 656         entry = &queue->entries[queue->index[index]];
 657
 658         spin_unlock_irqrestore(&queue->lock, irqflags);
 659
 660         return entry;
 661 }
 662 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
 663
 664 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 665 {
 666         unsigned long irqflags;
 667
 668         if (unlikely(index >= Q_INDEX_MAX)) {
 669                 ERROR(queue->rt2x00dev,
 670                       "Index change on invalid index type (%d)\n", index);
 671                 return;
 672         }
 673
 674         spin_lock_irqsave(&queue->lock, irqflags);
 675
 676         queue->index[index]++;
 677         if (queue->index[index] >= queue->limit)
 678                 queue->index[index] = 0;
 679
 680         if (index == Q_INDEX) {
 681                 queue->length++;
 682         } else if (index == Q_INDEX_DONE) {
 683                 queue->length--;
 684                 queue->count++;
 685         }
 686
 687         spin_unlock_irqrestore(&queue->lock, irqflags);
 688 }
 689
 690 static void rt2x00queue_reset(struct data_queue *queue)
 691 {
 692         unsigned long irqflags;
 693
 694         spin_lock_irqsave(&queue->lock, irqflags);
 695
 696         queue->count = 0;
 697         queue->length = 0;
 698         memset(queue->index, 0, sizeof(queue->index));
 699
 700         spin_unlock_irqrestore(&queue->lock, irqflags);
 701 }
 702
 703 void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev)
 704 {
 705         struct data_queue *queue;
 706
 707         txall_queue_for_each(rt2x00dev, queue)
 708                 rt2x00dev->ops->lib->kill_tx_queue(rt2x00dev, queue->qid);
 709 }
 710
 711 void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
 712 {
 713         struct data_queue *queue;
 714         unsigned int i;
 715
 716         queue_for_each(rt2x00dev, queue) {
 717                 rt2x00queue_reset(queue);
 718
 719                 for (i = 0; i < queue->limit; i++) {
 720                         queue->entries[i].flags = 0;
 721
 722                         rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
 723                 }
 724         }
 725 }
 726
 727 static int rt2x00queue_alloc_entries(struct data_queue *queue,
 728                                      const struct data_queue_desc *qdesc)
 729 {
 730         struct queue_entry *entries;
 731         unsigned int entry_size;
 732         unsigned int i;
 733
 734         rt2x00queue_reset(queue);
 735
 736         queue->limit = qdesc->entry_num;
 737         queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
 738         queue->data_size = qdesc->data_size;
 739         queue->desc_size = qdesc->desc_size;
 740
 741         /*
 742          * Allocate all queue entries.
 743          */
 744         entry_size = sizeof(*entries) + qdesc->priv_size;
 745         entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
 746         if (!entries)
 747                 return -ENOMEM;
 748
 749 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
 750         ( ((char *)(__base)) + ((__limit) * (__esize)) + \
 751             ((__index) * (__psize)) )
 752
 753         for (i = 0; i < queue->limit; i++) {
 754                 entries[i].flags = 0;
 755                 entries[i].queue = queue;
 756                 entries[i].skb = NULL;
 757                 entries[i].entry_idx = i;
 758                 entries[i].priv_data =
 759                     QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
 760                                             sizeof(*entries), qdesc->priv_size);
 761         }
 762
 763 #undef QUEUE_ENTRY_PRIV_OFFSET
 764
 765         queue->entries = entries;
 766
 767         return 0;
 768 }
 769
 770 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
 771                                   struct data_queue *queue)
 772 {
 773         unsigned int i;
 774
 775         if (!queue->entries)
 776                 return;
 777
 778         for (i = 0; i < queue->limit; i++) {
 779                 if (queue->entries[i].skb)
 780                         rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
 781         }
 782 }
 783
 784 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
 785                                     struct data_queue *queue)
 786 {
 787         unsigned int i;
 788         struct sk_buff *skb;
 789
 790         for (i = 0; i < queue->limit; i++) {
 791                 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
 792                 if (!skb)
 793                         return -ENOMEM;
 794                 queue->entries[i].skb = skb;
 795         }
 796
 797         return 0;
 798 }
 799
 800 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
 801 {
 802         struct data_queue *queue;
 803         int status;
 804
 805         status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
 806         if (status)
 807                 goto exit;
 808
 809         tx_queue_for_each(rt2x00dev, queue) {
 810                 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
 811                 if (status)
 812                         goto exit;
 813         }
 814
 815         status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
 816         if (status)
 817                 goto exit;
 818
 819         if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
 820                 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
 821                                                    rt2x00dev->ops->atim);
 822                 if (status)
 823                         goto exit;
 824         }
 825
 826         status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
 827         if (status)
 828                 goto exit;
 829
 830         return 0;
 831
 832 exit:
 833         ERROR(rt2x00dev, "Queue entries allocation failed.\n");
 834
 835         rt2x00queue_uninitialize(rt2x00dev);
 836
 837         return status;
 838 }
 839
 840 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
 841 {
 842         struct data_queue *queue;
 843
 844         rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
 845
 846         queue_for_each(rt2x00dev, queue) {
 847                 kfree(queue->entries);
 848                 queue->entries = NULL;
 849         }
 850 }
 851
 852 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
 853                              struct data_queue *queue, enum data_queue_qid qid)
 854 {
 855         spin_lock_init(&queue->lock);
 856
 857         queue->rt2x00dev = rt2x00dev;
 858         queue->qid = qid;
 859         queue->txop = 0;
 860         queue->aifs = 2;
 861         queue->cw_min = 5;
 862         queue->cw_max = 10;
 863 }
 864
 865 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
 866 {
 867         struct data_queue *queue;
 868         enum data_queue_qid qid;
 869         unsigned int req_atim =
 870             !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 871
 872         /*
 873          * We need the following queues:
 874          * RX: 1
 875          * TX: ops->tx_queues
 876          * Beacon: 1
 877          * Atim: 1 (if required)
 878          */
 879         rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
 880
 881         queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
 882         if (!queue) {
 883                 ERROR(rt2x00dev, "Queue allocation failed.\n");
 884                 return -ENOMEM;
 885         }
 886
 887         /*
 888          * Initialize pointers
 889          */
 890         rt2x00dev->rx = queue;
 891         rt2x00dev->tx = &queue[1];
 892         rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
 893
 894         /*
 895          * Initialize queue parameters.
 896          * RX: qid = QID_RX
 897          * TX: qid = QID_AC_BE + index
 898          * TX: cw_min: 2^5 = 32.
 899          * TX: cw_max: 2^10 = 1024.
 900          * BCN: qid = QID_BEACON
 901          * ATIM: qid = QID_ATIM
 902          */
 903         rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
 904
 905         qid = QID_AC_BE;
 906         tx_queue_for_each(rt2x00dev, queue)
 907                 rt2x00queue_init(rt2x00dev, queue, qid++);
 908
 909         rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
 910         if (req_atim)
 911                 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
 912
 913         return 0;
 914 }
 915
 916 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
 917 {
 918         kfree(rt2x00dev->rx);
 919         rt2x00dev->rx = NULL;
 920         rt2x00dev->tx = NULL;
 921         rt2x00dev->bcn = NULL;
 922 }