net/mac80211/wme.c

   1 /*
   2  * Copyright 2004, Instant802 Networks, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/netdevice.h>
  10 #include <linux/skbuff.h>
  11 #include <linux/module.h>
  12 #include <linux/if_arp.h>
  13 #include <linux/types.h>
  14 #include <net/ip.h>
  15 #include <net/pkt_sched.h>
  16
  17 #include <net/mac80211.h>
  18 #include "ieee80211_i.h"
  19 #include "wme.h"
  20
  21 /* maximum number of hardware queues we support. */
  22 #define TC_80211_MAX_QUEUES 16
  23
  24 const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 };
  25
  26 struct ieee80211_sched_data
  27 {
  28         unsigned long qdisc_pool[BITS_TO_LONGS(TC_80211_MAX_QUEUES)];
  29         struct tcf_proto *filter_list;
  30         struct Qdisc *queues[TC_80211_MAX_QUEUES];
  31         struct sk_buff_head requeued[TC_80211_MAX_QUEUES];
  32 };
  33
  34 static const char llc_ip_hdr[8] = {0xAA, 0xAA, 0x3, 0, 0, 0, 0x08, 0};
  35
  36 /* given a data frame determine the 802.1p/1d tag to use */
  37 static inline unsigned classify_1d(struct sk_buff *skb, struct Qdisc *qd)
  38 {
  39         struct iphdr *ip;
  40         int dscp;
  41         int offset;
  42
  43         struct ieee80211_sched_data *q = qdisc_priv(qd);
  44         struct tcf_result res = { -1, 0 };
  45
  46         /* if there is a user set filter list, call out to that */
  47         if (q->filter_list) {
  48                 tc_classify(skb, q->filter_list, &res);
  49                 if (res.class != -1)
  50                         return res.class;
  51         }
  52
  53         /* skb->priority values from 256->263 are magic values to
  54          * directly indicate a specific 802.1d priority.
  55          * This is used to allow 802.1d priority to be passed directly in
  56          * from VLAN tags, etc. */
  57         if (skb->priority >= 256 && skb->priority <= 263)
  58                 return skb->priority - 256;
  59
  60         /* check there is a valid IP header present */
  61         offset = ieee80211_get_hdrlen_from_skb(skb);
  62         if (skb->len < offset + sizeof(llc_ip_hdr) + sizeof(*ip) ||
  63             memcmp(skb->data + offset, llc_ip_hdr, sizeof(llc_ip_hdr)))
  64                 return 0;
  65
  66         ip = (struct iphdr *) (skb->data + offset + sizeof(llc_ip_hdr));
  67
  68         dscp = ip->tos & 0xfc;
  69         if (dscp & 0x1c)
  70                 return 0;
  71         return dscp >> 5;
  72 }
  73
  74
  75 static inline int wme_downgrade_ac(struct sk_buff *skb)
  76 {
  77         switch (skb->priority) {
  78         case 6:
  79         case 7:
  80                 skb->priority = 5; /* VO -> VI */
  81                 return 0;
  82         case 4:
  83         case 5:
  84                 skb->priority = 3; /* VI -> BE */
  85                 return 0;
  86         case 0:
  87         case 3:
  88                 skb->priority = 2; /* BE -> BK */
  89                 return 0;
  90         default:
  91                 return -1;
  92         }
  93 }
  94
  95
  96 /* positive return value indicates which queue to use
  97  * negative return value indicates to drop the frame */
  98 static inline int classify80211(struct sk_buff *skb, struct Qdisc *qd)
  99 {
 100         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 101         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 102         unsigned short fc = le16_to_cpu(hdr->frame_control);
 103         int qos;
 104
 105         /* see if frame is data or non data frame */
 106         if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) {
 107                 /* management frames go on AC_VO queue, but are sent
 108                 * without QoS control fields */
 109                 return IEEE80211_TX_QUEUE_DATA0;
 110         }
 111
 112         if (0 /* injected */) {
 113                 /* use AC from radiotap */
 114         }
 115
 116         /* is this a QoS frame? */
 117         qos = fc & IEEE80211_STYPE_QOS_DATA;
 118
 119         if (!qos) {
 120                 skb->priority = 0; /* required for correct WPA/11i MIC */
 121                 return ieee802_1d_to_ac[skb->priority];
 122         }
 123
 124         /* use the data classifier to determine what 802.1d tag the
 125          * data frame has */
 126         skb->priority = classify_1d(skb, qd);
 127
 128         /* in case we are a client verify acm is not set for this ac */
 129         while (unlikely(local->wmm_acm & BIT(skb->priority))) {
 130                 if (wme_downgrade_ac(skb)) {
 131                         /* No AC with lower priority has acm=0, drop packet. */
 132                         return -1;
 133                 }
 134         }
 135
 136         /* look up which queue to use for frames with this 1d tag */
 137         return ieee802_1d_to_ac[skb->priority];
 138 }
 139
 140
 141 static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
 142 {
 143         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 144         struct ieee80211_sched_data *q = qdisc_priv(qd);
 145         struct ieee80211_tx_packet_data *pkt_data =
 146                 (struct ieee80211_tx_packet_data *) skb->cb;
 147         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 148         unsigned short fc = le16_to_cpu(hdr->frame_control);
 149         struct Qdisc *qdisc;
 150         int err, queue;
 151         struct sta_info *sta;
 152         u8 tid;
 153
 154         if (pkt_data->flags & IEEE80211_TXPD_REQUEUE) {
 155                 queue = pkt_data->queue;
 156                 rcu_read_lock();
 157                 sta = sta_info_get(local, hdr->addr1);
 158                 tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
 159                 if (sta) {
 160                         int ampdu_queue = sta->tid_to_tx_q[tid];
 161                         if ((ampdu_queue < local->hw.queues) &&
 162                             test_bit(ampdu_queue, q->qdisc_pool)) {
 163                                 queue = ampdu_queue;
 164                                 pkt_data->flags |= IEEE80211_TXPD_AMPDU;
 165                         } else {
 166                                 pkt_data->flags &= ~IEEE80211_TXPD_AMPDU;
 167                         }
 168                 }
 169                 rcu_read_unlock();
 170                 skb_queue_tail(&q->requeued[queue], skb);
 171                 qd->q.qlen++;
 172                 return 0;
 173         }
 174
 175         queue = classify80211(skb, qd);
 176
 177         /* now we know the 1d priority, fill in the QoS header if there is one
 178          */
 179         if (WLAN_FC_IS_QOS_DATA(fc)) {
 180                 u8 *p = skb->data + ieee80211_get_hdrlen(fc) - 2;
 181                 u8 ack_policy = 0;
 182                 tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
 183                 if (local->wifi_wme_noack_test)
 184                         ack_policy |= QOS_CONTROL_ACK_POLICY_NOACK <<
 185                                         QOS_CONTROL_ACK_POLICY_SHIFT;
 186                 /* qos header is 2 bytes, second reserved */
 187                 *p = ack_policy | tid;
 188                 p++;
 189                 *p = 0;
 190
 191                 rcu_read_lock();
 192
 193                 sta = sta_info_get(local, hdr->addr1);
 194                 if (sta) {
 195                         int ampdu_queue = sta->tid_to_tx_q[tid];
 196                         if ((ampdu_queue < local->hw.queues) &&
 197                                 test_bit(ampdu_queue, q->qdisc_pool)) {
 198                                 queue = ampdu_queue;
 199                                 pkt_data->flags |= IEEE80211_TXPD_AMPDU;
 200                         } else {
 201                                 pkt_data->flags &= ~IEEE80211_TXPD_AMPDU;
 202                         }
 203                 }
 204
 205                 rcu_read_unlock();
 206         }
 207
 208         if (unlikely(queue >= local->hw.queues)) {
 209 #if 0
 210                 if (net_ratelimit()) {
 211                         printk(KERN_DEBUG "%s - queue=%d (hw does not "
 212                                "support) -> %d\n",
 213                                __func__, queue, local->hw.queues - 1);
 214                 }
 215 #endif
 216                 queue = local->hw.queues - 1;
 217         }
 218
 219         if (unlikely(queue < 0)) {
 220                         kfree_skb(skb);
 221                         err = NET_XMIT_DROP;
 222         } else {
 223                 tid = skb->priority & QOS_CONTROL_TAG1D_MASK;
 224                 pkt_data->queue = (unsigned int) queue;
 225                 qdisc = q->queues[queue];
 226                 err = qdisc->enqueue(skb, qdisc);
 227                 if (err == NET_XMIT_SUCCESS) {
 228                         qd->q.qlen++;
 229                         qd->bstats.bytes += skb->len;
 230                         qd->bstats.packets++;
 231                         return NET_XMIT_SUCCESS;
 232                 }
 233         }
 234         qd->qstats.drops++;
 235         return err;
 236 }
 237
 238
 239 /* TODO: clean up the cases where master_hard_start_xmit
 240  * returns non 0 - it shouldn't ever do that. Once done we
 241  * can remove this function */
 242 static int wme_qdiscop_requeue(struct sk_buff *skb, struct Qdisc* qd)
 243 {
 244         struct ieee80211_sched_data *q = qdisc_priv(qd);
 245         struct ieee80211_tx_packet_data *pkt_data =
 246                 (struct ieee80211_tx_packet_data *) skb->cb;
 247         struct Qdisc *qdisc;
 248         int err;
 249
 250         /* we recorded which queue to use earlier! */
 251         qdisc = q->queues[pkt_data->queue];
 252
 253         if ((err = qdisc->ops->requeue(skb, qdisc)) == 0) {
 254                 qd->q.qlen++;
 255                 return 0;
 256         }
 257         qd->qstats.drops++;
 258         return err;
 259 }
 260
 261
 262 static struct sk_buff *wme_qdiscop_dequeue(struct Qdisc* qd)
 263 {
 264         struct ieee80211_sched_data *q = qdisc_priv(qd);
 265         struct net_device *dev = qd->dev;
 266         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 267         struct ieee80211_hw *hw = &local->hw;
 268         struct sk_buff *skb;
 269         struct Qdisc *qdisc;
 270         int queue;
 271
 272         /* check all the h/w queues in numeric/priority order */
 273         for (queue = 0; queue < hw->queues; queue++) {
 274                 /* see if there is room in this hardware queue */
 275                 if ((test_bit(IEEE80211_LINK_STATE_XOFF,
 276                                 &local->state[queue])) ||
 277                     (test_bit(IEEE80211_LINK_STATE_PENDING,
 278                                 &local->state[queue])) ||
 279                          (!test_bit(queue, q->qdisc_pool)))
 280                         continue;
 281
 282                 /* there is space - try and get a frame */
 283                 skb = skb_dequeue(&q->requeued[queue]);
 284                 if (skb) {
 285                         qd->q.qlen--;
 286                         return skb;
 287                 }
 288
 289                 qdisc = q->queues[queue];
 290                 skb = qdisc->dequeue(qdisc);
 291                 if (skb) {
 292                         qd->q.qlen--;
 293                         return skb;
 294                 }
 295         }
 296         /* returning a NULL here when all the h/w queues are full means we
 297          * never need to call netif_stop_queue in the driver */
 298         return NULL;
 299 }
 300
 301
 302 static void wme_qdiscop_reset(struct Qdisc* qd)
 303 {
 304         struct ieee80211_sched_data *q = qdisc_priv(qd);
 305         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 306         struct ieee80211_hw *hw = &local->hw;
 307         int queue;
 308
 309         /* QUESTION: should we have some hardware flush functionality here? */
 310
 311         for (queue = 0; queue < hw->queues; queue++) {
 312                 skb_queue_purge(&q->requeued[queue]);
 313                 qdisc_reset(q->queues[queue]);
 314         }
 315         qd->q.qlen = 0;
 316 }
 317
 318
 319 static void wme_qdiscop_destroy(struct Qdisc* qd)
 320 {
 321         struct ieee80211_sched_data *q = qdisc_priv(qd);
 322         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 323         struct ieee80211_hw *hw = &local->hw;
 324         int queue;
 325
 326         tcf_destroy_chain(q->filter_list);
 327         q->filter_list = NULL;
 328
 329         for (queue=0; queue < hw->queues; queue++) {
 330                 skb_queue_purge(&q->requeued[queue]);
 331                 qdisc_destroy(q->queues[queue]);
 332                 q->queues[queue] = &noop_qdisc;
 333         }
 334 }
 335
 336
 337 /* called whenever parameters are updated on existing qdisc */
 338 static int wme_qdiscop_tune(struct Qdisc *qd, struct nlattr *opt)
 339 {
 340 /*      struct ieee80211_sched_data *q = qdisc_priv(qd);
 341 */
 342         /* check our options block is the right size */
 343         /* copy any options to our local structure */
 344 /*      Ignore options block for now - always use static mapping
 345         struct tc_ieee80211_qopt *qopt = nla_data(opt);
 346
 347         if (opt->nla_len < nla_attr_size(sizeof(*qopt)))
 348                 return -EINVAL;
 349         memcpy(q->tag2queue, qopt->tag2queue, sizeof(qopt->tag2queue));
 350 */
 351         return 0;
 352 }
 353
 354
 355 /* called during initial creation of qdisc on device */
 356 static int wme_qdiscop_init(struct Qdisc *qd, struct nlattr *opt)
 357 {
 358         struct ieee80211_sched_data *q = qdisc_priv(qd);
 359         struct net_device *dev = qd->dev;
 360         struct ieee80211_local *local;
 361         int queues;
 362         int err = 0, i;
 363
 364         /* check that device is a mac80211 device */
 365         if (!dev->ieee80211_ptr ||
 366             dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
 367                 return -EINVAL;
 368
 369         /* check this device is an ieee80211 master type device */
 370         if (dev->type != ARPHRD_IEEE80211)
 371                 return -EINVAL;
 372
 373         /* check that there is no qdisc currently attached to device
 374          * this ensures that we will be the root qdisc. (I can't find a better
 375          * way to test this explicitly) */
 376         if (dev->qdisc_sleeping != &noop_qdisc)
 377                 return -EINVAL;
 378
 379         if (qd->flags & TCQ_F_INGRESS)
 380                 return -EINVAL;
 381
 382         local = wdev_priv(dev->ieee80211_ptr);
 383         queues = local->hw.queues;
 384
 385         /* if options were passed in, set them */
 386         if (opt) {
 387                 err = wme_qdiscop_tune(qd, opt);
 388         }
 389
 390         /* create child queues */
 391         for (i = 0; i < queues; i++) {
 392                 skb_queue_head_init(&q->requeued[i]);
 393                 q->queues[i] = qdisc_create_dflt(qd->dev, &pfifo_qdisc_ops,
 394                                                  qd->handle);
 395                 if (!q->queues[i]) {
 396                         q->queues[i] = &noop_qdisc;
 397                         printk(KERN_ERR "%s child qdisc %i creation failed", dev->name, i);
 398                 }
 399         }
 400
 401         /* reserve all legacy QoS queues */
 402         for (i = 0; i < min(IEEE80211_TX_QUEUE_DATA4, queues); i++)
 403                 set_bit(i, q->qdisc_pool);
 404
 405         return err;
 406 }
 407
 408 static int wme_qdiscop_dump(struct Qdisc *qd, struct sk_buff *skb)
 409 {
 410 /*      struct ieee80211_sched_data *q = qdisc_priv(qd);
 411         unsigned char *p = skb->tail;
 412         struct tc_ieee80211_qopt opt;
 413
 414         memcpy(&opt.tag2queue, q->tag2queue, TC_80211_MAX_TAG + 1);
 415         NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
 416 */      return skb->len;
 417 /*
 418 nla_put_failure:
 419         skb_trim(skb, p - skb->data);*/
 420         return -1;
 421 }
 422
 423
 424 static int wme_classop_graft(struct Qdisc *qd, unsigned long arg,
 425                              struct Qdisc *new, struct Qdisc **old)
 426 {
 427         struct ieee80211_sched_data *q = qdisc_priv(qd);
 428         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 429         struct ieee80211_hw *hw = &local->hw;
 430         unsigned long queue = arg - 1;
 431
 432         if (queue >= hw->queues)
 433                 return -EINVAL;
 434
 435         if (!new)
 436                 new = &noop_qdisc;
 437
 438         sch_tree_lock(qd);
 439         *old = q->queues[queue];
 440         q->queues[queue] = new;
 441         qdisc_reset(*old);
 442         sch_tree_unlock(qd);
 443
 444         return 0;
 445 }
 446
 447
 448 static struct Qdisc *
 449 wme_classop_leaf(struct Qdisc *qd, unsigned long arg)
 450 {
 451         struct ieee80211_sched_data *q = qdisc_priv(qd);
 452         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 453         struct ieee80211_hw *hw = &local->hw;
 454         unsigned long queue = arg - 1;
 455
 456         if (queue >= hw->queues)
 457                 return NULL;
 458
 459         return q->queues[queue];
 460 }
 461
 462
 463 static unsigned long wme_classop_get(struct Qdisc *qd, u32 classid)
 464 {
 465         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 466         struct ieee80211_hw *hw = &local->hw;
 467         unsigned long queue = TC_H_MIN(classid);
 468
 469         if (queue - 1 >= hw->queues)
 470                 return 0;
 471
 472         return queue;
 473 }
 474
 475
 476 static unsigned long wme_classop_bind(struct Qdisc *qd, unsigned long parent,
 477                                       u32 classid)
 478 {
 479         return wme_classop_get(qd, classid);
 480 }
 481
 482
 483 static void wme_classop_put(struct Qdisc *q, unsigned long cl)
 484 {
 485 }
 486
 487
 488 static int wme_classop_change(struct Qdisc *qd, u32 handle, u32 parent,
 489                               struct nlattr **tca, unsigned long *arg)
 490 {
 491         unsigned long cl = *arg;
 492         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 493         struct ieee80211_hw *hw = &local->hw;
 494
 495         if (cl - 1 > hw->queues)
 496                 return -ENOENT;
 497
 498         /* TODO: put code to program hardware queue parameters here,
 499          * to allow programming from tc command line */
 500
 501         return 0;
 502 }
 503
 504
 505 /* we don't support deleting hardware queues
 506  * when we add WMM-SA support - TSPECs may be deleted here */
 507 static int wme_classop_delete(struct Qdisc *qd, unsigned long cl)
 508 {
 509         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 510         struct ieee80211_hw *hw = &local->hw;
 511
 512         if (cl - 1 > hw->queues)
 513                 return -ENOENT;
 514         return 0;
 515 }
 516
 517
 518 static int wme_classop_dump_class(struct Qdisc *qd, unsigned long cl,
 519                                   struct sk_buff *skb, struct tcmsg *tcm)
 520 {
 521         struct ieee80211_sched_data *q = qdisc_priv(qd);
 522         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 523         struct ieee80211_hw *hw = &local->hw;
 524
 525         if (cl - 1 > hw->queues)
 526                 return -ENOENT;
 527         tcm->tcm_handle = TC_H_MIN(cl);
 528         tcm->tcm_parent = qd->handle;
 529         tcm->tcm_info = q->queues[cl-1]->handle; /* do we need this? */
 530         return 0;
 531 }
 532
 533
 534 static void wme_classop_walk(struct Qdisc *qd, struct qdisc_walker *arg)
 535 {
 536         struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 537         struct ieee80211_hw *hw = &local->hw;
 538         int queue;
 539
 540         if (arg->stop)
 541                 return;
 542
 543         for (queue = 0; queue < hw->queues; queue++) {
 544                 if (arg->count < arg->skip) {
 545                         arg->count++;
 546                         continue;
 547                 }
 548                 /* we should return classids for our internal queues here
 549                  * as well as the external ones */
 550                 if (arg->fn(qd, queue+1, arg) < 0) {
 551                         arg->stop = 1;
 552                         break;
 553                 }
 554                 arg->count++;
 555         }
 556 }
 557
 558
 559 static struct tcf_proto ** wme_classop_find_tcf(struct Qdisc *qd,
 560                                                 unsigned long cl)
 561 {
 562         struct ieee80211_sched_data *q = qdisc_priv(qd);
 563
 564         if (cl)
 565                 return NULL;
 566
 567         return &q->filter_list;
 568 }
 569
 570
 571 /* this qdisc is classful (i.e. has classes, some of which may have leaf qdiscs attached)
 572  * - these are the operations on the classes */
 573 static const struct Qdisc_class_ops class_ops =
 574 {
 575         .graft = wme_classop_graft,
 576         .leaf = wme_classop_leaf,
 577
 578         .get = wme_classop_get,
 579         .put = wme_classop_put,
 580         .change = wme_classop_change,
 581         .delete = wme_classop_delete,
 582         .walk = wme_classop_walk,
 583
 584         .tcf_chain = wme_classop_find_tcf,
 585         .bind_tcf = wme_classop_bind,
 586         .unbind_tcf = wme_classop_put,
 587
 588         .dump = wme_classop_dump_class,
 589 };
 590
 591
 592 /* queueing discipline operations */
 593 static struct Qdisc_ops wme_qdisc_ops __read_mostly =
 594 {
 595         .next = NULL,
 596         .cl_ops = &class_ops,
 597         .id = "ieee80211",
 598         .priv_size = sizeof(struct ieee80211_sched_data),
 599
 600         .enqueue = wme_qdiscop_enqueue,
 601         .dequeue = wme_qdiscop_dequeue,
 602         .requeue = wme_qdiscop_requeue,
 603         .drop = NULL, /* drop not needed since we are always the root qdisc */
 604
 605         .init = wme_qdiscop_init,
 606         .reset = wme_qdiscop_reset,
 607         .destroy = wme_qdiscop_destroy,
 608         .change = wme_qdiscop_tune,
 609
 610         .dump = wme_qdiscop_dump,
 611 };
 612
 613
 614 void ieee80211_install_qdisc(struct net_device *dev)
 615 {
 616         struct Qdisc *qdisc;
 617
 618         qdisc = qdisc_create_dflt(dev, &wme_qdisc_ops, TC_H_ROOT);
 619         if (!qdisc) {
 620                 printk(KERN_ERR "%s: qdisc installation failed\n", dev->name);
 621                 return;
 622         }
 623
 624         /* same handle as would be allocated by qdisc_alloc_handle() */
 625         qdisc->handle = 0x80010000;
 626
 627         qdisc_lock_tree(dev);
 628         list_add_tail(&qdisc->list, &dev->qdisc_list);
 629         dev->qdisc_sleeping = qdisc;
 630         qdisc_unlock_tree(dev);
 631 }
 632
 633
 634 int ieee80211_qdisc_installed(struct net_device *dev)
 635 {
 636         return dev->qdisc_sleeping->ops == &wme_qdisc_ops;
 637 }
 638
 639
 640 int ieee80211_wme_register(void)
 641 {
 642         return register_qdisc(&wme_qdisc_ops);
 643 }
 644
 645
 646 void ieee80211_wme_unregister(void)
 647 {
 648         unregister_qdisc(&wme_qdisc_ops);
 649 }
 650
 651 int ieee80211_ht_agg_queue_add(struct ieee80211_local *local,
 652                         struct sta_info *sta, u16 tid)
 653 {
 654         int i;
 655         struct ieee80211_sched_data *q =
 656                         qdisc_priv(local->mdev->qdisc_sleeping);
 657         DECLARE_MAC_BUF(mac);
 658
 659         /* prepare the filter and save it for the SW queue
 660          * matching the recieved HW queue */
 661
 662         /* try to get a Qdisc from the pool */
 663         for (i = IEEE80211_TX_QUEUE_BEACON; i < local->hw.queues; i++)
 664                 if (!test_and_set_bit(i, q->qdisc_pool)) {
 665                         ieee80211_stop_queue(local_to_hw(local), i);
 666                         sta->tid_to_tx_q[tid] = i;
 667
 668                         /* IF there are already pending packets
 669                          * on this tid first we need to drain them
 670                          * on the previous queue
 671                          * since HT is strict in order */
 672 #ifdef CONFIG_MAC80211_HT_DEBUG
 673                         if (net_ratelimit())
 674                                 printk(KERN_DEBUG "allocated aggregation queue"
 675                                         " %d tid %d addr %s pool=0x%lX",
 676                                         i, tid, print_mac(mac, sta->addr),
 677                                         q->qdisc_pool[0]);
 678 #endif /* CONFIG_MAC80211_HT_DEBUG */
 679                         return 0;
 680                 }
 681
 682         return -EAGAIN;
 683 }
 684
 685 /**
 686  * the caller needs to hold local->mdev->queue_lock
 687  */
 688 void ieee80211_ht_agg_queue_remove(struct ieee80211_local *local,
 689                                    struct sta_info *sta, u16 tid,
 690                                    u8 requeue)
 691 {
 692         struct ieee80211_sched_data *q =
 693                 qdisc_priv(local->mdev->qdisc_sleeping);
 694         int agg_queue = sta->tid_to_tx_q[tid];
 695
 696         /* return the qdisc to the pool */
 697         clear_bit(agg_queue, q->qdisc_pool);
 698         sta->tid_to_tx_q[tid] = local->hw.queues;
 699
 700         if (requeue)
 701                 ieee80211_requeue(local, agg_queue);
 702         else
 703                 q->queues[agg_queue]->ops->reset(q->queues[agg_queue]);
 704 }
 705
 706 void ieee80211_requeue(struct ieee80211_local *local, int queue)
 707 {
 708         struct Qdisc *root_qd = local->mdev->qdisc_sleeping;
 709         struct ieee80211_sched_data *q = qdisc_priv(root_qd);
 710         struct Qdisc *qdisc = q->queues[queue];
 711         struct sk_buff *skb = NULL;
 712         u32 len;
 713
 714         if (!qdisc || !qdisc->dequeue)
 715                 return;
 716
 717         printk(KERN_DEBUG "requeue: qlen = %d\n", qdisc->q.qlen);
 718         for (len = qdisc->q.qlen; len > 0; len--) {
 719                 skb = qdisc->dequeue(qdisc);
 720                 root_qd->q.qlen--;
 721                 /* packet will be classified again and */
 722                 /* skb->packet_data->queue will be overridden if needed */
 723                 if (skb)
 724                         wme_qdiscop_enqueue(skb, root_qd);
 725         }
 726 }