drivers/net/wireless/rt2x00/rt2x00queue.c

   1 /*
   2         Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
   3         Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
   4         Copyright (C) 2004 - 2009 Gertjan van Wingerde <gwingerde@gmail.com>
   5         <http://rt2x00.serialmonkey.com>
   6
   7         This program is free software; you can redistribute it and/or modify
   8         it under the terms of the GNU General Public License as published by
   9         the Free Software Foundation; either version 2 of the License, or
  10         (at your option) any later version.
  11
  12         This program is distributed in the hope that it will be useful,
  13         but WITHOUT ANY WARRANTY; without even the implied warranty of
  14         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15         GNU General Public License for more details.
  16
  17         You should have received a copy of the GNU General Public License
  18         along with this program; if not, write to the
  19         Free Software Foundation, Inc.,
  20         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 /*
  24         Module: rt2x00lib
  25         Abstract: rt2x00 queue specific routines.
  26  */
  27
  28 #include <linux/slab.h>
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/dma-mapping.h>
  32
  33 #include "rt2x00.h"
  34 #include "rt2x00lib.h"
  35
  36 struct sk_buff *rt2x00queue_alloc_rxskb(struct queue_entry *entry)
  37 {
  38         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
  39         struct sk_buff *skb;
  40         struct skb_frame_desc *skbdesc;
  41         unsigned int frame_size;
  42         unsigned int head_size = 0;
  43         unsigned int tail_size = 0;
  44
  45         /*
  46          * The frame size includes descriptor size, because the
  47          * hardware directly receive the frame into the skbuffer.
  48          */
  49         frame_size = entry->queue->data_size + entry->queue->desc_size;
  50
  51         /*
  52          * The payload should be aligned to a 4-byte boundary,
  53          * this means we need at least 3 bytes for moving the frame
  54          * into the correct offset.
  55          */
  56         head_size = 4;
  57
  58         /*
  59          * For IV/EIV/ICV assembly we must make sure there is
  60          * at least 8 bytes bytes available in headroom for IV/EIV
  61          * and 8 bytes for ICV data as tailroon.
  62          */
  63         if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
  64                 head_size += 8;
  65                 tail_size += 8;
  66         }
  67
  68         /*
  69          * Allocate skbuffer.
  70          */
  71         skb = dev_alloc_skb(frame_size + head_size + tail_size);
  72         if (!skb)
  73                 return NULL;
  74
  75         /*
  76          * Make sure we not have a frame with the requested bytes
  77          * available in the head and tail.
  78          */
  79         skb_reserve(skb, head_size);
  80         skb_put(skb, frame_size);
  81
  82         /*
  83          * Populate skbdesc.
  84          */
  85         skbdesc = get_skb_frame_desc(skb);
  86         memset(skbdesc, 0, sizeof(*skbdesc));
  87         skbdesc->entry = entry;
  88
  89         if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) {
  90                 skbdesc->skb_dma = dma_map_single(rt2x00dev->dev,
  91                                                   skb->data,
  92                                                   skb->len,
  93                                                   DMA_FROM_DEVICE);
  94                 skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
  95         }
  96
  97         return skb;
  98 }
  99
 100 void rt2x00queue_map_txskb(struct queue_entry *entry)
 101 {
 102         struct device *dev = entry->queue->rt2x00dev->dev;
 103         struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
 104
 105         skbdesc->skb_dma =
 106             dma_map_single(dev, entry->skb->data, entry->skb->len, DMA_TO_DEVICE);
 107         skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
 108 }
 109 EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
 110
 111 void rt2x00queue_unmap_skb(struct queue_entry *entry)
 112 {
 113         struct device *dev = entry->queue->rt2x00dev->dev;
 114         struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
 115
 116         if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
 117                 dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len,
 118                                  DMA_FROM_DEVICE);
 119                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
 120         } else if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
 121                 dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len,
 122                                  DMA_TO_DEVICE);
 123                 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
 124         }
 125 }
 126 EXPORT_SYMBOL_GPL(rt2x00queue_unmap_skb);
 127
 128 void rt2x00queue_free_skb(struct queue_entry *entry)
 129 {
 130         if (!entry->skb)
 131                 return;
 132
 133         rt2x00queue_unmap_skb(entry);
 134         dev_kfree_skb_any(entry->skb);
 135         entry->skb = NULL;
 136 }
 137
 138 void rt2x00queue_align_frame(struct sk_buff *skb)
 139 {
 140         unsigned int frame_length = skb->len;
 141         unsigned int align = ALIGN_SIZE(skb, 0);
 142
 143         if (!align)
 144                 return;
 145
 146         skb_push(skb, align);
 147         memmove(skb->data, skb->data + align, frame_length);
 148         skb_trim(skb, frame_length);
 149 }
 150
 151 void rt2x00queue_align_payload(struct sk_buff *skb, unsigned int header_length)
 152 {
 153         unsigned int frame_length = skb->len;
 154         unsigned int align = ALIGN_SIZE(skb, header_length);
 155
 156         if (!align)
 157                 return;
 158
 159         skb_push(skb, align);
 160         memmove(skb->data, skb->data + align, frame_length);
 161         skb_trim(skb, frame_length);
 162 }
 163
 164 void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int header_length)
 165 {
 166         unsigned int payload_length = skb->len - header_length;
 167         unsigned int header_align = ALIGN_SIZE(skb, 0);
 168         unsigned int payload_align = ALIGN_SIZE(skb, header_length);
 169         unsigned int l2pad = payload_length ? L2PAD_SIZE(header_length) : 0;
 170
 171         /*
 172          * Adjust the header alignment if the payload needs to be moved more
 173          * than the header.
 174          */
 175         if (payload_align > header_align)
 176                 header_align += 4;
 177
 178         /* There is nothing to do if no alignment is needed */
 179         if (!header_align)
 180                 return;
 181
 182         /* Reserve the amount of space needed in front of the frame */
 183         skb_push(skb, header_align);
 184
 185         /*
 186          * Move the header.
 187          */
 188         memmove(skb->data, skb->data + header_align, header_length);
 189
 190         /* Move the payload, if present and if required */
 191         if (payload_length && payload_align)
 192                 memmove(skb->data + header_length + l2pad,
 193                         skb->data + header_length + l2pad + payload_align,
 194                         payload_length);
 195
 196         /* Trim the skb to the correct size */
 197         skb_trim(skb, header_length + l2pad + payload_length);
 198 }
 199
 200 void rt2x00queue_remove_l2pad(struct sk_buff *skb, unsigned int header_length)
 201 {
 202         /*
 203          * L2 padding is only present if the skb contains more than just the
 204          * IEEE 802.11 header.
 205          */
 206         unsigned int l2pad = (skb->len > header_length) ?
 207                                 L2PAD_SIZE(header_length) : 0;
 208
 209         if (!l2pad)
 210                 return;
 211
 212         memmove(skb->data + l2pad, skb->data, header_length);
 213         skb_pull(skb, l2pad);
 214 }
 215
 216 static void rt2x00queue_create_tx_descriptor_seq(struct queue_entry *entry,
 217                                                  struct txentry_desc *txdesc)
 218 {
 219         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 220         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 221         struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif);
 222         unsigned long irqflags;
 223
 224         if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) ||
 225             unlikely(!tx_info->control.vif))
 226                 return;
 227
 228         /*
 229          * Hardware should insert sequence counter.
 230          * FIXME: We insert a software sequence counter first for
 231          * hardware that doesn't support hardware sequence counting.
 232          *
 233          * This is wrong because beacons are not getting sequence
 234          * numbers assigned properly.
 235          *
 236          * A secondary problem exists for drivers that cannot toggle
 237          * sequence counting per-frame, since those will override the
 238          * sequence counter given by mac80211.
 239          */
 240         spin_lock_irqsave(&intf->seqlock, irqflags);
 241
 242         if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
 243                 intf->seqno += 0x10;
 244         hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
 245         hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
 246
 247         spin_unlock_irqrestore(&intf->seqlock, irqflags);
 248
 249         __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
 250 }
 251
 252 static void rt2x00queue_create_tx_descriptor_plcp(struct queue_entry *entry,
 253                                                   struct txentry_desc *txdesc,
 254                                                   const struct rt2x00_rate *hwrate)
 255 {
 256         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 257         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 258         struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
 259         unsigned int data_length;
 260         unsigned int duration;
 261         unsigned int residual;
 262
 263         /* Data length + CRC + Crypto overhead (IV/EIV/ICV/MIC) */
 264         data_length = entry->skb->len + 4;
 265         data_length += rt2x00crypto_tx_overhead(rt2x00dev, entry->skb);
 266
 267         /*
 268          * PLCP setup
 269          * Length calculation depends on OFDM/CCK rate.
 270          */
 271         txdesc->signal = hwrate->plcp;
 272         txdesc->service = 0x04;
 273
 274         if (hwrate->flags & DEV_RATE_OFDM) {
 275                 txdesc->length_high = (data_length >> 6) & 0x3f;
 276                 txdesc->length_low = data_length & 0x3f;
 277         } else {
 278                 /*
 279                  * Convert length to microseconds.
 280                  */
 281                 residual = GET_DURATION_RES(data_length, hwrate->bitrate);
 282                 duration = GET_DURATION(data_length, hwrate->bitrate);
 283
 284                 if (residual != 0) {
 285                         duration++;
 286
 287                         /*
 288                          * Check if we need to set the Length Extension
 289                          */
 290                         if (hwrate->bitrate == 110 && residual <= 30)
 291                                 txdesc->service |= 0x80;
 292                 }
 293
 294                 txdesc->length_high = (duration >> 8) & 0xff;
 295                 txdesc->length_low = duration & 0xff;
 296
 297                 /*
 298                  * When preamble is enabled we should set the
 299                  * preamble bit for the signal.
 300                  */
 301                 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
 302                         txdesc->signal |= 0x08;
 303         }
 304 }
 305
 306 static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
 307                                              struct txentry_desc *txdesc)
 308 {
 309         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 310         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
 311         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
 312         struct ieee80211_rate *rate =
 313             ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
 314         const struct rt2x00_rate *hwrate;
 315
 316         memset(txdesc, 0, sizeof(*txdesc));
 317
 318         /*
 319          * Header and frame information.
 320          */
 321         txdesc->length = entry->skb->len;
 322         txdesc->header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
 323
 324         /*
 325          * Check whether this frame is to be acked.
 326          */
 327         if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
 328                 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
 329
 330         /*
 331          * Check if this is a RTS/CTS frame
 332          */
 333         if (ieee80211_is_rts(hdr->frame_control) ||
 334             ieee80211_is_cts(hdr->frame_control)) {
 335                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 336                 if (ieee80211_is_rts(hdr->frame_control))
 337                         __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
 338                 else
 339                         __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
 340                 if (tx_info->control.rts_cts_rate_idx >= 0)
 341                         rate =
 342                             ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
 343         }
 344
 345         /*
 346          * Determine retry information.
 347          */
 348         txdesc->retry_limit = tx_info->control.rates[0].count - 1;
 349         if (txdesc->retry_limit >= rt2x00dev->long_retry)
 350                 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
 351
 352         /*
 353          * Check if more fragments are pending
 354          */
 355         if (ieee80211_has_morefrags(hdr->frame_control)) {
 356                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 357                 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
 358         }
 359
 360         /*
 361          * Check if more frames (!= fragments) are pending
 362          */
 363         if (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES)
 364                 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
 365
 366         /*
 367          * Beacons and probe responses require the tsf timestamp
 368          * to be inserted into the frame, except for a frame that has been injected
 369          * through a monitor interface. This latter is needed for testing a
 370          * monitor interface.
 371          */
 372         if ((ieee80211_is_beacon(hdr->frame_control) ||
 373             ieee80211_is_probe_resp(hdr->frame_control)) &&
 374             (!(tx_info->flags & IEEE80211_TX_CTL_INJECTED)))
 375                 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
 376
 377         /*
 378          * Determine with what IFS priority this frame should be send.
 379          * Set ifs to IFS_SIFS when the this is not the first fragment,
 380          * or this fragment came after RTS/CTS.
 381          */
 382         if ((tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) &&
 383             !test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
 384                 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
 385                 txdesc->ifs = IFS_BACKOFF;
 386         } else
 387                 txdesc->ifs = IFS_SIFS;
 388
 389         /*
 390          * Determine rate modulation.
 391          */
 392         hwrate = rt2x00_get_rate(rate->hw_value);
 393         txdesc->rate_mode = RATE_MODE_CCK;
 394         if (hwrate->flags & DEV_RATE_OFDM)
 395                 txdesc->rate_mode = RATE_MODE_OFDM;
 396
 397         /*
 398          * Apply TX descriptor handling by components
 399          */
 400         rt2x00crypto_create_tx_descriptor(entry, txdesc);
 401         rt2x00ht_create_tx_descriptor(entry, txdesc, hwrate);
 402         rt2x00queue_create_tx_descriptor_seq(entry, txdesc);
 403         rt2x00queue_create_tx_descriptor_plcp(entry, txdesc, hwrate);
 404 }
 405
 406 static int rt2x00queue_write_tx_data(struct queue_entry *entry,
 407                                      struct txentry_desc *txdesc)
 408 {
 409         struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
 410
 411         /*
 412          * This should not happen, we already checked the entry
 413          * was ours. When the hardware disagrees there has been
 414          * a queue corruption!
 415          */
 416         if (unlikely(rt2x00dev->ops->lib->get_entry_state &&
 417                      rt2x00dev->ops->lib->get_entry_state(entry))) {
 418                 ERROR(rt2x00dev,
 419                       "Corrupt queue %d, accessing entry which is not ours.\n"
 420                       "Please file bug report to %s.\n",
 421                       entry->queue->qid, DRV_PROJECT);
 422                 return -EINVAL;
 423         }
 424
 425         /*
 426          * Add the requested extra tx headroom in front of the skb.
 427          */
 428         skb_push(entry->skb, rt2x00dev->ops->extra_tx_headroom);
 429         memset(entry->skb->data, 0, rt2x00dev->ops->extra_tx_headroom);
 430
 431         /*
 432          * Call the driver's write_tx_data function, if it exists.
 433          */
 434         if (rt2x00dev->ops->lib->write_tx_data)
 435                 rt2x00dev->ops->lib->write_tx_data(entry, txdesc);
 436
 437         /*
 438          * Map the skb to DMA.
 439          */
 440         if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags))
 441                 rt2x00queue_map_txskb(entry);
 442
 443         return 0;
 444 }
 445
 446 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
 447                                             struct txentry_desc *txdesc)
 448 {
 449         struct data_queue *queue = entry->queue;
 450
 451         queue->rt2x00dev->ops->lib->write_tx_desc(entry, txdesc);
 452
 453         /*
 454          * All processing on the frame has been completed, this means
 455          * it is now ready to be dumped to userspace through debugfs.
 456          */
 457         rt2x00debug_dump_frame(queue->rt2x00dev, DUMP_FRAME_TX, entry->skb);
 458 }
 459
 460 static void rt2x00queue_kick_tx_queue(struct data_queue *queue,
 461                                       struct txentry_desc *txdesc)
 462 {
 463         /*
 464          * Check if we need to kick the queue, there are however a few rules
 465          *      1) Don't kick unless this is the last in frame in a burst.
 466          *         When the burst flag is set, this frame is always followed
 467          *         by another frame which in some way are related to eachother.
 468          *         This is true for fragments, RTS or CTS-to-self frames.
 469          *      2) Rule 1 can be broken when the available entries
 470          *         in the queue are less then a certain threshold.
 471          */
 472         if (rt2x00queue_threshold(queue) ||
 473             !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
 474                 queue->rt2x00dev->ops->lib->kick_queue(queue);
 475 }
 476
 477 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb,
 478                                bool local)
 479 {
 480         struct ieee80211_tx_info *tx_info;
 481         struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
 482         struct txentry_desc txdesc;
 483         struct skb_frame_desc *skbdesc;
 484         u8 rate_idx, rate_flags;
 485
 486         if (unlikely(rt2x00queue_full(queue)))
 487                 return -ENOBUFS;
 488
 489         if (unlikely(test_and_set_bit(ENTRY_OWNER_DEVICE_DATA,
 490                                       &entry->flags))) {
 491                 ERROR(queue->rt2x00dev,
 492                       "Arrived at non-free entry in the non-full queue %d.\n"
 493                       "Please file bug report to %s.\n",
 494                       queue->qid, DRV_PROJECT);
 495                 return -EINVAL;
 496         }
 497
 498         /*
 499          * Copy all TX descriptor information into txdesc,
 500          * after that we are free to use the skb->cb array
 501          * for our information.
 502          */
 503         entry->skb = skb;
 504         rt2x00queue_create_tx_descriptor(entry, &txdesc);
 505
 506         /*
 507          * All information is retrieved from the skb->cb array,
 508          * now we should claim ownership of the driver part of that
 509          * array, preserving the bitrate index and flags.
 510          */
 511         tx_info = IEEE80211_SKB_CB(skb);
 512         rate_idx = tx_info->control.rates[0].idx;
 513         rate_flags = tx_info->control.rates[0].flags;
 514         skbdesc = get_skb_frame_desc(skb);
 515         memset(skbdesc, 0, sizeof(*skbdesc));
 516         skbdesc->entry = entry;
 517         skbdesc->tx_rate_idx = rate_idx;
 518         skbdesc->tx_rate_flags = rate_flags;
 519
 520         if (local)
 521                 skbdesc->flags |= SKBDESC_NOT_MAC80211;
 522
 523         /*
 524          * When hardware encryption is supported, and this frame
 525          * is to be encrypted, we should strip the IV/EIV data from
 526          * the frame so we can provide it to the driver separately.
 527          */
 528         if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
 529             !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
 530                 if (test_bit(DRIVER_REQUIRE_COPY_IV, &queue->rt2x00dev->flags))
 531                         rt2x00crypto_tx_copy_iv(skb, &txdesc);
 532                 else
 533                         rt2x00crypto_tx_remove_iv(skb, &txdesc);
 534         }
 535
 536         /*
 537          * When DMA allocation is required we should guarentee to the
 538          * driver that the DMA is aligned to a 4-byte boundary.
 539          * However some drivers require L2 padding to pad the payload
 540          * rather then the header. This could be a requirement for
 541          * PCI and USB devices, while header alignment only is valid
 542          * for PCI devices.
 543          */
 544         if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
 545                 rt2x00queue_insert_l2pad(entry->skb, txdesc.header_length);
 546         else if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
 547                 rt2x00queue_align_frame(entry->skb);
 548
 549         /*
 550          * It could be possible that the queue was corrupted and this
 551          * call failed. Since we always return NETDEV_TX_OK to mac80211,
 552          * this frame will simply be dropped.
 553          */
 554         if (unlikely(rt2x00queue_write_tx_data(entry, &txdesc))) {
 555                 clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
 556                 entry->skb = NULL;
 557                 return -EIO;
 558         }
 559
 560         set_bit(ENTRY_DATA_PENDING, &entry->flags);
 561
 562         rt2x00queue_index_inc(queue, Q_INDEX);
 563         rt2x00queue_write_tx_descriptor(entry, &txdesc);
 564         rt2x00queue_kick_tx_queue(queue, &txdesc);
 565
 566         return 0;
 567 }
 568
 569 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
 570                               struct ieee80211_vif *vif,
 571                               const bool enable_beacon)
 572 {
 573         struct rt2x00_intf *intf = vif_to_intf(vif);
 574         struct skb_frame_desc *skbdesc;
 575         struct txentry_desc txdesc;
 576
 577         if (unlikely(!intf->beacon))
 578                 return -ENOBUFS;
 579
 580         mutex_lock(&intf->beacon_skb_mutex);
 581
 582         /*
 583          * Clean up the beacon skb.
 584          */
 585         rt2x00queue_free_skb(intf->beacon);
 586
 587         if (!enable_beacon) {
 588                 rt2x00queue_stop_queue(intf->beacon->queue);
 589                 mutex_unlock(&intf->beacon_skb_mutex);
 590                 return 0;
 591         }
 592
 593         intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
 594         if (!intf->beacon->skb) {
 595                 mutex_unlock(&intf->beacon_skb_mutex);
 596                 return -ENOMEM;
 597         }
 598
 599         /*
 600          * Copy all TX descriptor information into txdesc,
 601          * after that we are free to use the skb->cb array
 602          * for our information.
 603          */
 604         rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
 605
 606         /*
 607          * Fill in skb descriptor
 608          */
 609         skbdesc = get_skb_frame_desc(intf->beacon->skb);
 610         memset(skbdesc, 0, sizeof(*skbdesc));
 611         skbdesc->entry = intf->beacon;
 612
 613         /*
 614          * Send beacon to hardware and enable beacon genaration..
 615          */
 616         rt2x00dev->ops->lib->write_beacon(intf->beacon, &txdesc);
 617
 618         mutex_unlock(&intf->beacon_skb_mutex);
 619
 620         return 0;
 621 }
 622
 623 void rt2x00queue_for_each_entry(struct data_queue *queue,
 624                                 enum queue_index start,
 625                                 enum queue_index end,
 626                                 void (*fn)(struct queue_entry *entry))
 627 {
 628         unsigned long irqflags;
 629         unsigned int index_start;
 630         unsigned int index_end;
 631         unsigned int i;
 632
 633         if (unlikely(start >= Q_INDEX_MAX || end >= Q_INDEX_MAX)) {
 634                 ERROR(queue->rt2x00dev,
 635                       "Entry requested from invalid index range (%d - %d)\n",
 636                       start, end);
 637                 return;
 638         }
 639
 640         /*
 641          * Only protect the range we are going to loop over,
 642          * if during our loop a extra entry is set to pending
 643          * it should not be kicked during this run, since it
 644          * is part of another TX operation.
 645          */
 646         spin_lock_irqsave(&queue->index_lock, irqflags);
 647         index_start = queue->index[start];
 648         index_end = queue->index[end];
 649         spin_unlock_irqrestore(&queue->index_lock, irqflags);
 650
 651         /*
 652          * Start from the TX done pointer, this guarentees that we will
 653          * send out all frames in the correct order.
 654          */
 655         if (index_start < index_end) {
 656                 for (i = index_start; i < index_end; i++)
 657                         fn(&queue->entries[i]);
 658         } else {
 659                 for (i = index_start; i < queue->limit; i++)
 660                         fn(&queue->entries[i]);
 661
 662                 for (i = 0; i < index_end; i++)
 663                         fn(&queue->entries[i]);
 664         }
 665 }
 666 EXPORT_SYMBOL_GPL(rt2x00queue_for_each_entry);
 667
 668 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
 669                                          const enum data_queue_qid queue)
 670 {
 671         int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
 672
 673         if (queue == QID_RX)
 674                 return rt2x00dev->rx;
 675
 676         if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
 677                 return &rt2x00dev->tx[queue];
 678
 679         if (!rt2x00dev->bcn)
 680                 return NULL;
 681
 682         if (queue == QID_BEACON)
 683                 return &rt2x00dev->bcn[0];
 684         else if (queue == QID_ATIM && atim)
 685                 return &rt2x00dev->bcn[1];
 686
 687         return NULL;
 688 }
 689 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
 690
 691 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
 692                                           enum queue_index index)
 693 {
 694         struct queue_entry *entry;
 695         unsigned long irqflags;
 696
 697         if (unlikely(index >= Q_INDEX_MAX)) {
 698                 ERROR(queue->rt2x00dev,
 699                       "Entry requested from invalid index type (%d)\n", index);
 700                 return NULL;
 701         }
 702
 703         spin_lock_irqsave(&queue->index_lock, irqflags);
 704
 705         entry = &queue->entries[queue->index[index]];
 706
 707         spin_unlock_irqrestore(&queue->index_lock, irqflags);
 708
 709         return entry;
 710 }
 711 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
 712
 713 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
 714 {
 715         unsigned long irqflags;
 716
 717         if (unlikely(index >= Q_INDEX_MAX)) {
 718                 ERROR(queue->rt2x00dev,
 719                       "Index change on invalid index type (%d)\n", index);
 720                 return;
 721         }
 722
 723         spin_lock_irqsave(&queue->index_lock, irqflags);
 724
 725         queue->index[index]++;
 726         if (queue->index[index] >= queue->limit)
 727                 queue->index[index] = 0;
 728
 729         queue->last_action[index] = jiffies;
 730
 731         if (index == Q_INDEX) {
 732                 queue->length++;
 733         } else if (index == Q_INDEX_DONE) {
 734                 queue->length--;
 735                 queue->count++;
 736         }
 737
 738         spin_unlock_irqrestore(&queue->index_lock, irqflags);
 739 }
 740
 741 void rt2x00queue_pause_queue(struct data_queue *queue)
 742 {
 743         if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
 744             !test_bit(QUEUE_STARTED, &queue->flags) ||
 745             test_and_set_bit(QUEUE_PAUSED, &queue->flags))
 746                 return;
 747
 748         switch (queue->qid) {
 749         case QID_AC_VO:
 750         case QID_AC_VI:
 751         case QID_AC_BE:
 752         case QID_AC_BK:
 753                 /*
 754                  * For TX queues, we have to disable the queue
 755                  * inside mac80211.
 756                  */
 757                 ieee80211_stop_queue(queue->rt2x00dev->hw, queue->qid);
 758                 break;
 759         default:
 760                 break;
 761         }
 762 }
 763 EXPORT_SYMBOL_GPL(rt2x00queue_pause_queue);
 764
 765 void rt2x00queue_unpause_queue(struct data_queue *queue)
 766 {
 767         if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
 768             !test_bit(QUEUE_STARTED, &queue->flags) ||
 769             !test_and_clear_bit(QUEUE_PAUSED, &queue->flags))
 770                 return;
 771
 772         switch (queue->qid) {
 773         case QID_AC_VO:
 774         case QID_AC_VI:
 775         case QID_AC_BE:
 776         case QID_AC_BK:
 777                 /*
 778                  * For TX queues, we have to enable the queue
 779                  * inside mac80211.
 780                  */
 781                 ieee80211_wake_queue(queue->rt2x00dev->hw, queue->qid);
 782                 break;
 783         case QID_RX:
 784                 /*
 785                  * For RX we need to kick the queue now in order to
 786                  * receive frames.
 787                  */
 788                 queue->rt2x00dev->ops->lib->kick_queue(queue);
 789         default:
 790                 break;
 791         }
 792 }
 793 EXPORT_SYMBOL_GPL(rt2x00queue_unpause_queue);
 794
 795 void rt2x00queue_start_queue(struct data_queue *queue)
 796 {
 797         mutex_lock(&queue->status_lock);
 798
 799         if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
 800             test_and_set_bit(QUEUE_STARTED, &queue->flags)) {
 801                 mutex_unlock(&queue->status_lock);
 802                 return;
 803         }
 804
 805         set_bit(QUEUE_PAUSED, &queue->flags);
 806
 807         queue->rt2x00dev->ops->lib->start_queue(queue);
 808
 809         rt2x00queue_unpause_queue(queue);
 810
 811         mutex_unlock(&queue->status_lock);
 812 }
 813 EXPORT_SYMBOL_GPL(rt2x00queue_start_queue);
 814
 815 void rt2x00queue_stop_queue(struct data_queue *queue)
 816 {
 817         mutex_lock(&queue->status_lock);
 818
 819         if (!test_and_clear_bit(QUEUE_STARTED, &queue->flags)) {
 820                 mutex_unlock(&queue->status_lock);
 821                 return;
 822         }
 823
 824         rt2x00queue_pause_queue(queue);
 825
 826         queue->rt2x00dev->ops->lib->stop_queue(queue);
 827
 828         mutex_unlock(&queue->status_lock);
 829 }
 830 EXPORT_SYMBOL_GPL(rt2x00queue_stop_queue);
 831
 832 void rt2x00queue_flush_queue(struct data_queue *queue, bool drop)
 833 {
 834         unsigned int i;
 835         bool started;
 836         bool tx_queue =
 837                 (queue->qid == QID_AC_VO) ||
 838                 (queue->qid == QID_AC_VI) ||
 839                 (queue->qid == QID_AC_BE) ||
 840                 (queue->qid == QID_AC_BK);
 841
 842         mutex_lock(&queue->status_lock);
 843
 844         /*
 845          * If the queue has been started, we must stop it temporarily
 846          * to prevent any new frames to be queued on the device. If
 847          * we are not dropping the pending frames, the queue must
 848          * only be stopped in the software and not the hardware,
 849          * otherwise the queue will never become empty on its own.
 850          */
 851         started = test_bit(QUEUE_STARTED, &queue->flags);
 852         if (started) {
 853                 /*
 854                  * Pause the queue
 855                  */
 856                 rt2x00queue_pause_queue(queue);
 857
 858                 /*
 859                  * If we are not supposed to drop any pending
 860                  * frames, this means we must force a start (=kick)
 861                  * to the queue to make sure the hardware will
 862                  * start transmitting.
 863                  */
 864                 if (!drop && tx_queue)
 865                         queue->rt2x00dev->ops->lib->kick_queue(queue);
 866         }
 867
 868         /*
 869          * Check if driver supports flushing, we can only guarentee
 870          * full support for flushing if the driver is able
 871          * to cancel all pending frames (drop = true).
 872          */
 873         if (drop && queue->rt2x00dev->ops->lib->flush_queue)
 874                 queue->rt2x00dev->ops->lib->flush_queue(queue);
 875
 876         /*
 877          * When we don't want to drop any frames, or when
 878          * the driver doesn't fully flush the queue correcly,
 879          * we must wait for the queue to become empty.
 880          */
 881         for (i = 0; !rt2x00queue_empty(queue) && i < 100; i++)
 882                 msleep(10);
 883
 884         /*
 885          * The queue flush has failed...
 886          */
 887         if (unlikely(!rt2x00queue_empty(queue)))
 888                 WARNING(queue->rt2x00dev, "Queue %d failed to flush", queue->qid);
 889
 890         /*
 891          * Restore the queue to the previous status
 892          */
 893         if (started)
 894                 rt2x00queue_unpause_queue(queue);
 895
 896         mutex_unlock(&queue->status_lock);
 897 }
 898 EXPORT_SYMBOL_GPL(rt2x00queue_flush_queue);
 899
 900 void rt2x00queue_start_queues(struct rt2x00_dev *rt2x00dev)
 901 {
 902         struct data_queue *queue;
 903
 904         /*
 905          * rt2x00queue_start_queue will call ieee80211_wake_queue
 906          * for each queue after is has been properly initialized.
 907          */
 908         tx_queue_for_each(rt2x00dev, queue)
 909                 rt2x00queue_start_queue(queue);
 910
 911         rt2x00queue_start_queue(rt2x00dev->rx);
 912 }
 913 EXPORT_SYMBOL_GPL(rt2x00queue_start_queues);
 914
 915 void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev)
 916 {
 917         struct data_queue *queue;
 918
 919         /*
 920          * rt2x00queue_stop_queue will call ieee80211_stop_queue
 921          * as well, but we are completely shutting doing everything
 922          * now, so it is much safer to stop all TX queues at once,
 923          * and use rt2x00queue_stop_queue for cleaning up.
 924          */
 925         ieee80211_stop_queues(rt2x00dev->hw);
 926
 927         tx_queue_for_each(rt2x00dev, queue)
 928                 rt2x00queue_stop_queue(queue);
 929
 930         rt2x00queue_stop_queue(rt2x00dev->rx);
 931 }
 932 EXPORT_SYMBOL_GPL(rt2x00queue_stop_queues);
 933
 934 void rt2x00queue_flush_queues(struct rt2x00_dev *rt2x00dev, bool drop)
 935 {
 936         struct data_queue *queue;
 937
 938         tx_queue_for_each(rt2x00dev, queue)
 939                 rt2x00queue_flush_queue(queue, drop);
 940
 941         rt2x00queue_flush_queue(rt2x00dev->rx, drop);
 942 }
 943 EXPORT_SYMBOL_GPL(rt2x00queue_flush_queues);
 944
 945 static void rt2x00queue_reset(struct data_queue *queue)
 946 {
 947         unsigned long irqflags;
 948         unsigned int i;
 949
 950         spin_lock_irqsave(&queue->index_lock, irqflags);
 951
 952         queue->count = 0;
 953         queue->length = 0;
 954
 955         for (i = 0; i < Q_INDEX_MAX; i++) {
 956                 queue->index[i] = 0;
 957                 queue->last_action[i] = jiffies;
 958         }
 959
 960         spin_unlock_irqrestore(&queue->index_lock, irqflags);
 961 }
 962
 963 void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
 964 {
 965         struct data_queue *queue;
 966         unsigned int i;
 967
 968         queue_for_each(rt2x00dev, queue) {
 969                 rt2x00queue_reset(queue);
 970
 971                 for (i = 0; i < queue->limit; i++)
 972                         rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
 973         }
 974 }
 975
 976 static int rt2x00queue_alloc_entries(struct data_queue *queue,
 977                                      const struct data_queue_desc *qdesc)
 978 {
 979         struct queue_entry *entries;
 980         unsigned int entry_size;
 981         unsigned int i;
 982
 983         rt2x00queue_reset(queue);
 984
 985         queue->limit = qdesc->entry_num;
 986         queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
 987         queue->data_size = qdesc->data_size;
 988         queue->desc_size = qdesc->desc_size;
 989
 990         /*
 991          * Allocate all queue entries.
 992          */
 993         entry_size = sizeof(*entries) + qdesc->priv_size;
 994         entries = kcalloc(queue->limit, entry_size, GFP_KERNEL);
 995         if (!entries)
 996                 return -ENOMEM;
 997
 998 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
 999         (((char *)(__base)) + ((__limit) * (__esize)) + \
1000             ((__index) * (__psize)))
1001
1002         for (i = 0; i < queue->limit; i++) {
1003                 entries[i].flags = 0;
1004                 entries[i].queue = queue;
1005                 entries[i].skb = NULL;
1006                 entries[i].entry_idx = i;
1007                 entries[i].priv_data =
1008                     QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
1009                                             sizeof(*entries), qdesc->priv_size);
1010         }
1011
1012 #undef QUEUE_ENTRY_PRIV_OFFSET
1013
1014         queue->entries = entries;
1015
1016         return 0;
1017 }
1018
1019 static void rt2x00queue_free_skbs(struct data_queue *queue)
1020 {
1021         unsigned int i;
1022
1023         if (!queue->entries)
1024                 return;
1025
1026         for (i = 0; i < queue->limit; i++) {
1027                 rt2x00queue_free_skb(&queue->entries[i]);
1028         }
1029 }
1030
1031 static int rt2x00queue_alloc_rxskbs(struct data_queue *queue)
1032 {
1033         unsigned int i;
1034         struct sk_buff *skb;
1035
1036         for (i = 0; i < queue->limit; i++) {
1037                 skb = rt2x00queue_alloc_rxskb(&queue->entries[i]);
1038                 if (!skb)
1039                         return -ENOMEM;
1040                 queue->entries[i].skb = skb;
1041         }
1042
1043         return 0;
1044 }
1045
1046 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
1047 {
1048         struct data_queue *queue;
1049         int status;
1050
1051         status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
1052         if (status)
1053                 goto exit;
1054
1055         tx_queue_for_each(rt2x00dev, queue) {
1056                 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
1057                 if (status)
1058                         goto exit;
1059         }
1060
1061         status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
1062         if (status)
1063                 goto exit;
1064
1065         if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
1066                 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
1067                                                    rt2x00dev->ops->atim);
1068                 if (status)
1069                         goto exit;
1070         }
1071
1072         status = rt2x00queue_alloc_rxskbs(rt2x00dev->rx);
1073         if (status)
1074                 goto exit;
1075
1076         return 0;
1077
1078 exit:
1079         ERROR(rt2x00dev, "Queue entries allocation failed.\n");
1080
1081         rt2x00queue_uninitialize(rt2x00dev);
1082
1083         return status;
1084 }
1085
1086 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
1087 {
1088         struct data_queue *queue;
1089
1090         rt2x00queue_free_skbs(rt2x00dev->rx);
1091
1092         queue_for_each(rt2x00dev, queue) {
1093                 kfree(queue->entries);
1094                 queue->entries = NULL;
1095         }
1096 }
1097
1098 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
1099                              struct data_queue *queue, enum data_queue_qid qid)
1100 {
1101         mutex_init(&queue->status_lock);
1102         spin_lock_init(&queue->index_lock);
1103
1104         queue->rt2x00dev = rt2x00dev;
1105         queue->qid = qid;
1106         queue->txop = 0;
1107         queue->aifs = 2;
1108         queue->cw_min = 5;
1109         queue->cw_max = 10;
1110 }
1111
1112 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
1113 {
1114         struct data_queue *queue;
1115         enum data_queue_qid qid;
1116         unsigned int req_atim =
1117             !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
1118
1119         /*
1120          * We need the following queues:
1121          * RX: 1
1122          * TX: ops->tx_queues
1123          * Beacon: 1
1124          * Atim: 1 (if required)
1125          */
1126         rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
1127
1128         queue = kcalloc(rt2x00dev->data_queues, sizeof(*queue), GFP_KERNEL);
1129         if (!queue) {
1130                 ERROR(rt2x00dev, "Queue allocation failed.\n");
1131                 return -ENOMEM;
1132         }
1133
1134         /*
1135          * Initialize pointers
1136          */
1137         rt2x00dev->rx = queue;
1138         rt2x00dev->tx = &queue[1];
1139         rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
1140
1141         /*
1142          * Initialize queue parameters.
1143          * RX: qid = QID_RX
1144          * TX: qid = QID_AC_VO + index
1145          * TX: cw_min: 2^5 = 32.
1146          * TX: cw_max: 2^10 = 1024.
1147          * BCN: qid = QID_BEACON
1148          * ATIM: qid = QID_ATIM
1149          */
1150         rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
1151
1152         qid = QID_AC_VO;
1153         tx_queue_for_each(rt2x00dev, queue)
1154                 rt2x00queue_init(rt2x00dev, queue, qid++);
1155
1156         rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
1157         if (req_atim)
1158                 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
1159
1160         return 0;
1161 }
1162
1163 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
1164 {
1165         kfree(rt2x00dev->rx);
1166         rt2x00dev->rx = NULL;
1167         rt2x00dev->tx = NULL;
1168         rt2x00dev->bcn = NULL;
1169 }