net/mac80211/wme.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright 2004, Instant802 Networks, Inc.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/netdevice.h>
 #include <linux/skbuff.h>
 #include <linux/module.h>
 #include <linux/if_arp.h>
 #include <linux/types.h>
 #include <net/ip.h>
 #include <net/pkt_sched.h>

 #include <net/mac80211.h>
 #include "ieee80211_i.h"
 #include "wme.h"

 /* maximum number of hardware queues we support. */
 #define TC_80211_MAX_QUEUES 8

 struct ieee80211_sched_data
 {
 	struct tcf_proto *filter_list;
 	struct Qdisc *queues[TC_80211_MAX_QUEUES];
 	struct sk_buff_head requeued[TC_80211_MAX_QUEUES];
 };

 static const char llc_ip_hdr[8] = {0xAA, 0xAA, 0x3, 0, 0, 0, 0x08, 0};

 /* given a data frame determine the 802.1p/1d tag to use */
 static inline unsigned classify_1d(struct sk_buff *skb, struct Qdisc *qd)
 {
 	struct iphdr *ip;
 	int dscp;
 	int offset;

 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct tcf_result res = { -1, 0 };

 	/* if there is a user set filter list, call out to that */
 	if (q->filter_list) {
 		tc_classify(skb, q->filter_list, &res);
 		if (res.class != -1)
 			return res.class;
 	}

 	/* skb->priority values from 256->263 are magic values to
 	 * directly indicate a specific 802.1d priority.
 	 * This is used to allow 802.1d priority to be passed directly in
 	 * from VLAN tags, etc. */
 	if (skb->priority >= 256 && skb->priority <= 263)
 		return skb->priority - 256;

 	/* check there is a valid IP header present */
 	offset = ieee80211_get_hdrlen_from_skb(skb);
 	if (skb->len < offset + sizeof(llc_ip_hdr) + sizeof(*ip) ||
 	    memcmp(skb->data + offset, llc_ip_hdr, sizeof(llc_ip_hdr)))
 		return 0;

 	ip = (struct iphdr *) (skb->data + offset + sizeof(llc_ip_hdr));

 	dscp = ip->tos & 0xfc;
 	if (dscp & 0x1c)
 		return 0;
 	return dscp >> 5;
 }


 static inline int wme_downgrade_ac(struct sk_buff *skb)
 {
 	switch (skb->priority) {
 	case 6:
 	case 7:
 		skb->priority = 5; /* VO -> VI */
 		return 0;
 	case 4:
 	case 5:
 		skb->priority = 3; /* VI -> BE */
 		return 0;
 	case 0:
 	case 3:
 		skb->priority = 2; /* BE -> BK */
 		return 0;
 	default:
 		return -1;
 	}
 }


 /* positive return value indicates which queue to use
  * negative return value indicates to drop the frame */
 static inline int classify80211(struct sk_buff *skb, struct Qdisc *qd)
 {
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 	unsigned short fc = le16_to_cpu(hdr->frame_control);
 	int qos;
 	const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 };

 	/* see if frame is data or non data frame */
 	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) {
 		/* management frames go on AC_VO queue, but are sent
 		* without QoS control fields */
 		return IEEE80211_TX_QUEUE_DATA0;
 	}

 	if (0 /* injected */) {
 		/* use AC from radiotap */
 	}

 	/* is this a QoS frame? */
 	qos = fc & IEEE80211_STYPE_QOS_DATA;

 	if (!qos) {
 		skb->priority = 0; /* required for correct WPA/11i MIC */
 		return ieee802_1d_to_ac[skb->priority];
 	}

 	/* use the data classifier to determine what 802.1d tag the
 	 * data frame has */
 	skb->priority = classify_1d(skb, qd);

 	/* in case we are a client verify acm is not set for this ac */
 	while (unlikely(local->wmm_acm & BIT(skb->priority))) {
 		if (wme_downgrade_ac(skb)) {
 			/* No AC with lower priority has acm=0, drop packet. */
 			return -1;
 		}
 	}

 	/* look up which queue to use for frames with this 1d tag */
 	return ieee802_1d_to_ac[skb->priority];
 }


 static int wme_qdiscop_enqueue(struct sk_buff *skb, struct Qdisc* qd)
 {
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_tx_packet_data *pkt_data =
 		(struct ieee80211_tx_packet_data *) skb->cb;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 	unsigned short fc = le16_to_cpu(hdr->frame_control);
 	struct Qdisc *qdisc;
 	int err, queue;

 	if (pkt_data->flags & IEEE80211_TXPD_REQUEUE) {
 		skb_queue_tail(&q->requeued[pkt_data->queue], skb);
 		qd->q.qlen++;
 		return 0;
 	}

 	queue = classify80211(skb, qd);

 	/* now we know the 1d priority, fill in the QoS header if there is one
 	 */
 	if (WLAN_FC_IS_QOS_DATA(fc)) {
 		u8 *p = skb->data + ieee80211_get_hdrlen(fc) - 2;
 		u8 qos_hdr = skb->priority & QOS_CONTROL_TAG1D_MASK;
 		if (local->wifi_wme_noack_test)
 			qos_hdr |= QOS_CONTROL_ACK_POLICY_NOACK <<
 					QOS_CONTROL_ACK_POLICY_SHIFT;
 		/* qos header is 2 bytes, second reserved */
 		*p = qos_hdr;
 		p++;
 		*p = 0;
 	}

 	if (unlikely(queue >= local->hw.queues)) {
 #if 0
 		if (net_ratelimit()) {
 			printk(KERN_DEBUG "%s - queue=%d (hw does not "
 			       "support) -> %d\n",
 			       __func__, queue, local->hw.queues - 1);
 		}
 #endif
 		queue = local->hw.queues - 1;
 	}

 	if (unlikely(queue < 0)) {
 			kfree_skb(skb);
 			err = NET_XMIT_DROP;
 	} else {
 		pkt_data->queue = (unsigned int) queue;
 		qdisc = q->queues[queue];
 		err = qdisc->enqueue(skb, qdisc);
 		if (err == NET_XMIT_SUCCESS) {
 			qd->q.qlen++;
 			qd->bstats.bytes += skb->len;
 			qd->bstats.packets++;
 			return NET_XMIT_SUCCESS;
 		}
 	}
 	qd->qstats.drops++;
 	return err;
 }


 /* TODO: clean up the cases where master_hard_start_xmit
  * returns non 0 - it shouldn't ever do that. Once done we
  * can remove this function */
 static int wme_qdiscop_requeue(struct sk_buff *skb, struct Qdisc* qd)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_tx_packet_data *pkt_data =
 		(struct ieee80211_tx_packet_data *) skb->cb;
 	struct Qdisc *qdisc;
 	int err;

 	/* we recorded which queue to use earlier! */
 	qdisc = q->queues[pkt_data->queue];

 	if ((err = qdisc->ops->requeue(skb, qdisc)) == 0) {
 		qd->q.qlen++;
 		return 0;
 	}
 	qd->qstats.drops++;
 	return err;
 }


 static struct sk_buff *wme_qdiscop_dequeue(struct Qdisc* qd)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct net_device *dev = qd->dev;
 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	struct sk_buff *skb;
 	struct Qdisc *qdisc;
 	int queue;

 	/* check all the h/w queues in numeric/priority order */
 	for (queue = 0; queue < hw->queues; queue++) {
 		/* see if there is room in this hardware queue */
 		if (test_bit(IEEE80211_LINK_STATE_XOFF,
 			     &local->state[queue]) ||
 		    test_bit(IEEE80211_LINK_STATE_PENDING,
 			     &local->state[queue]))
 			continue;

 		/* there is space - try and get a frame */
 		skb = skb_dequeue(&q->requeued[queue]);
 		if (skb) {
 			qd->q.qlen--;
 			return skb;
 		}

 		qdisc = q->queues[queue];
 		skb = qdisc->dequeue(qdisc);
 		if (skb) {
 			qd->q.qlen--;
 			return skb;
 		}
 	}
 	/* returning a NULL here when all the h/w queues are full means we
 	 * never need to call netif_stop_queue in the driver */
 	return NULL;
 }


 static void wme_qdiscop_reset(struct Qdisc* qd)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	int queue;

 	/* QUESTION: should we have some hardware flush functionality here? */

 	for (queue = 0; queue < hw->queues; queue++) {
 		skb_queue_purge(&q->requeued[queue]);
 		qdisc_reset(q->queues[queue]);
 	}
 	qd->q.qlen = 0;
 }


 static void wme_qdiscop_destroy(struct Qdisc* qd)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	int queue;

 	tcf_destroy_chain(q->filter_list);
 	q->filter_list = NULL;

 	for (queue=0; queue < hw->queues; queue++) {
 		skb_queue_purge(&q->requeued[queue]);
 		qdisc_destroy(q->queues[queue]);
 		q->queues[queue] = &noop_qdisc;
 	}
 }


 /* called whenever parameters are updated on existing qdisc */
 static int wme_qdiscop_tune(struct Qdisc *qd, struct rtattr *opt)
 {
 /*	struct ieee80211_sched_data *q = qdisc_priv(qd);
 */
 	/* check our options block is the right size */
 	/* copy any options to our local structure */
 /*	Ignore options block for now - always use static mapping
 	struct tc_ieee80211_qopt *qopt = RTA_DATA(opt);

 	if (opt->rta_len < RTA_LENGTH(sizeof(*qopt)))
 		return -EINVAL;
 	memcpy(q->tag2queue, qopt->tag2queue, sizeof(qopt->tag2queue));
 */
 	return 0;
 }


 /* called during initial creation of qdisc on device */
 static int wme_qdiscop_init(struct Qdisc *qd, struct rtattr *opt)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct net_device *dev = qd->dev;
 	struct ieee80211_local *local;
 	int queues;
 	int err = 0, i;

 	/* check that device is a mac80211 device */
 	if (!dev->ieee80211_ptr ||
 	    dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
 		return -EINVAL;

 	/* check this device is an ieee80211 master type device */
 	if (dev->type != ARPHRD_IEEE80211)
 		return -EINVAL;

 	/* check that there is no qdisc currently attached to device
 	 * this ensures that we will be the root qdisc. (I can't find a better
 	 * way to test this explicitly) */
 	if (dev->qdisc_sleeping != &noop_qdisc)
 		return -EINVAL;

 	if (qd->flags & TCQ_F_INGRESS)
 		return -EINVAL;

 	local = wdev_priv(dev->ieee80211_ptr);
 	queues = local->hw.queues;

 	/* if options were passed in, set them */
 	if (opt) {
 		err = wme_qdiscop_tune(qd, opt);
 	}

 	/* create child queues */
 	for (i = 0; i < queues; i++) {
 		skb_queue_head_init(&q->requeued[i]);
 		q->queues[i] = qdisc_create_dflt(qd->dev, &pfifo_qdisc_ops,
 						 qd->handle);
 		if (!q->queues[i]) {
 			q->queues[i] = &noop_qdisc;
 			printk(KERN_ERR "%s child qdisc %i creation failed", dev->name, i);
 		}
 	}

 	return err;
 }

 static int wme_qdiscop_dump(struct Qdisc *qd, struct sk_buff *skb)
 {
 /*	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	unsigned char *p = skb->tail;
 	struct tc_ieee80211_qopt opt;

 	memcpy(&opt.tag2queue, q->tag2queue, TC_80211_MAX_TAG + 1);
 	RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
 */	return skb->len;
 /*
 rtattr_failure:
 	skb_trim(skb, p - skb->data);*/
 	return -1;
 }


 static int wme_classop_graft(struct Qdisc *qd, unsigned long arg,
 			     struct Qdisc *new, struct Qdisc **old)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	unsigned long queue = arg - 1;

 	if (queue >= hw->queues)
 		return -EINVAL;

 	if (!new)
 		new = &noop_qdisc;

 	sch_tree_lock(qd);
 	*old = q->queues[queue];
 	q->queues[queue] = new;
 	qdisc_reset(*old);
 	sch_tree_unlock(qd);

 	return 0;
 }


 static struct Qdisc *
 wme_classop_leaf(struct Qdisc *qd, unsigned long arg)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	unsigned long queue = arg - 1;

 	if (queue >= hw->queues)
 		return NULL;

 	return q->queues[queue];
 }


 static unsigned long wme_classop_get(struct Qdisc *qd, u32 classid)
 {
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	unsigned long queue = TC_H_MIN(classid);

 	if (queue - 1 >= hw->queues)
 		return 0;

 	return queue;
 }


 static unsigned long wme_classop_bind(struct Qdisc *qd, unsigned long parent,
 				      u32 classid)
 {
 	return wme_classop_get(qd, classid);
 }


 static void wme_classop_put(struct Qdisc *q, unsigned long cl)
 {
 }


 static int wme_classop_change(struct Qdisc *qd, u32 handle, u32 parent,
 			      struct rtattr **tca, unsigned long *arg)
 {
 	unsigned long cl = *arg;
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;

 	if (cl - 1 > hw->queues)
 		return -ENOENT;

 	/* TODO: put code to program hardware queue parameters here,
 	 * to allow programming from tc command line */

 	return 0;
 }


 /* we don't support deleting hardware queues
  * when we add WMM-SA support - TSPECs may be deleted here */
 static int wme_classop_delete(struct Qdisc *qd, unsigned long cl)
 {
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;

 	if (cl - 1 > hw->queues)
 		return -ENOENT;
 	return 0;
 }


 static int wme_classop_dump_class(struct Qdisc *qd, unsigned long cl,
 				  struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;

 	if (cl - 1 > hw->queues)
 		return -ENOENT;
 	tcm->tcm_handle = TC_H_MIN(cl);
 	tcm->tcm_parent = qd->handle;
 	tcm->tcm_info = q->queues[cl-1]->handle; /* do we need this? */
 	return 0;
 }


 static void wme_classop_walk(struct Qdisc *qd, struct qdisc_walker *arg)
 {
 	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
 	struct ieee80211_hw *hw = &local->hw;
 	int queue;

 	if (arg->stop)
 		return;

 	for (queue = 0; queue < hw->queues; queue++) {
 		if (arg->count < arg->skip) {
 			arg->count++;
 			continue;
 		}
 		/* we should return classids for our internal queues here
 		 * as well as the external ones */
 		if (arg->fn(qd, queue+1, arg) < 0) {
 			arg->stop = 1;
 			break;
 		}
 		arg->count++;
 	}
 }


 static struct tcf_proto ** wme_classop_find_tcf(struct Qdisc *qd,
 						unsigned long cl)
 {
 	struct ieee80211_sched_data *q = qdisc_priv(qd);

 	if (cl)
 		return NULL;

 	return &q->filter_list;
 }


 /* this qdisc is classful (i.e. has classes, some of which may have leaf qdiscs attached)
  * - these are the operations on the classes */
 static const struct Qdisc_class_ops class_ops =
 {
 	.graft = wme_classop_graft,
 	.leaf = wme_classop_leaf,

 	.get = wme_classop_get,
 	.put = wme_classop_put,
 	.change = wme_classop_change,
 	.delete = wme_classop_delete,
 	.walk = wme_classop_walk,

 	.tcf_chain = wme_classop_find_tcf,
 	.bind_tcf = wme_classop_bind,
 	.unbind_tcf = wme_classop_put,

 	.dump = wme_classop_dump_class,
 };


 /* queueing discipline operations */
 static struct Qdisc_ops wme_qdisc_ops __read_mostly =
 {
 	.next = NULL,
 	.cl_ops = &class_ops,
 	.id = "ieee80211",
 	.priv_size = sizeof(struct ieee80211_sched_data),

 	.enqueue = wme_qdiscop_enqueue,
 	.dequeue = wme_qdiscop_dequeue,
 	.requeue = wme_qdiscop_requeue,
 	.drop = NULL, /* drop not needed since we are always the root qdisc */

 	.init = wme_qdiscop_init,
 	.reset = wme_qdiscop_reset,
 	.destroy = wme_qdiscop_destroy,
 	.change = wme_qdiscop_tune,

 	.dump = wme_qdiscop_dump,
 };


 void ieee80211_install_qdisc(struct net_device *dev)
 {
 	struct Qdisc *qdisc;

 	qdisc = qdisc_create_dflt(dev, &wme_qdisc_ops, TC_H_ROOT);
 	if (!qdisc) {
 		printk(KERN_ERR "%s: qdisc installation failed\n", dev->name);
 		return;
 	}

 	/* same handle as would be allocated by qdisc_alloc_handle() */
 	qdisc->handle = 0x80010000;

 	qdisc_lock_tree(dev);
 	list_add_tail(&qdisc->list, &dev->qdisc_list);
 	dev->qdisc_sleeping = qdisc;
 	qdisc_unlock_tree(dev);
 }


 int ieee80211_qdisc_installed(struct net_device *dev)
 {
 	return dev->qdisc_sleeping->ops == &wme_qdisc_ops;
 }


 int ieee80211_wme_register(void)
 {
 	return register_qdisc(&wme_qdisc_ops);
 }


 void ieee80211_wme_unregister(void)
 {
 	unregister_qdisc(&wme_qdisc_ops);
 }
	/*
	* Copyright 2004, Instant802 Networks, Inc.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/netdevice.h>
	#include <linux/skbuff.h>
	#include <linux/module.h>
	#include <linux/if_arp.h>
	#include <linux/types.h>
	#include <net/ip.h>
	#include <net/pkt_sched.h>

	#include <net/mac80211.h>
	#include "ieee80211_i.h"
	#include "wme.h"

	/* maximum number of hardware queues we support. */
	#define TC_80211_MAX_QUEUES 8

	struct ieee80211_sched_data
	{
	struct tcf_proto *filter_list;
	struct Qdisc *queues[TC_80211_MAX_QUEUES];
	struct sk_buff_head requeued[TC_80211_MAX_QUEUES];
	};

	static const char llc_ip_hdr[8] = {0xAA, 0xAA, 0x3, 0, 0, 0, 0x08, 0};

	/* given a data frame determine the 802.1p/1d tag to use */
	static inline unsigned classify_1d(struct sk_buff skb, struct Qdisc qd)
	{
	struct iphdr *ip;
	int dscp;
	int offset;

	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct tcf_result res = { -1, 0 };

	/* if there is a user set filter list, call out to that */
	if (q->filter_list) {
	tc_classify(skb, q->filter_list, &res);
	if (res.class != -1)
	return res.class;
	}

	/* skb->priority values from 256->263 are magic values to
	* directly indicate a specific 802.1d priority.
	* This is used to allow 802.1d priority to be passed directly in
	* from VLAN tags, etc. */
	if (skb->priority >= 256 && skb->priority <= 263)
	return skb->priority - 256;

	/* check there is a valid IP header present */
	offset = ieee80211_get_hdrlen_from_skb(skb);
	if (skb->len < offset + sizeof(llc_ip_hdr) + sizeof(*ip) \|\|
	memcmp(skb->data + offset, llc_ip_hdr, sizeof(llc_ip_hdr)))
	return 0;

	ip = (struct iphdr *) (skb->data + offset + sizeof(llc_ip_hdr));

	dscp = ip->tos & 0xfc;
	if (dscp & 0x1c)
	return 0;
	return dscp >> 5;
	}


	static inline int wme_downgrade_ac(struct sk_buff *skb)
	{
	switch (skb->priority) {
	case 6:
	case 7:
	skb->priority = 5; /* VO -> VI */
	return 0;
	case 4:
	case 5:
	skb->priority = 3; /* VI -> BE */
	return 0;
	case 0:
	case 3:
	skb->priority = 2; /* BE -> BK */
	return 0;
	default:
	return -1;
	}
	}


	/* positive return value indicates which queue to use
	* negative return value indicates to drop the frame */
	static inline int classify80211(struct sk_buff skb, struct Qdisc qd)
	{
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	unsigned short fc = le16_to_cpu(hdr->frame_control);
	int qos;
	const int ieee802_1d_to_ac[8] = { 2, 3, 3, 2, 1, 1, 0, 0 };

	/* see if frame is data or non data frame */
	if (unlikely((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)) {
	/* management frames go on AC_VO queue, but are sent
	* without QoS control fields */
	return IEEE80211_TX_QUEUE_DATA0;
	}

	if (0 /* injected */) {
	/* use AC from radiotap */
	}

	/* is this a QoS frame? */
	qos = fc & IEEE80211_STYPE_QOS_DATA;

	if (!qos) {
	skb->priority = 0; /* required for correct WPA/11i MIC */
	return ieee802_1d_to_ac[skb->priority];
	}

	/* use the data classifier to determine what 802.1d tag the
	* data frame has */
	skb->priority = classify_1d(skb, qd);

	/* in case we are a client verify acm is not set for this ac */
	while (unlikely(local->wmm_acm & BIT(skb->priority))) {
	if (wme_downgrade_ac(skb)) {
	/* No AC with lower priority has acm=0, drop packet. */
	return -1;
	}
	}

	/* look up which queue to use for frames with this 1d tag */
	return ieee802_1d_to_ac[skb->priority];
	}


	static int wme_qdiscop_enqueue(struct sk_buff skb, struct Qdisc qd)
	{
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_tx_packet_data *pkt_data =
	(struct ieee80211_tx_packet_data *) skb->cb;
	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	unsigned short fc = le16_to_cpu(hdr->frame_control);
	struct Qdisc *qdisc;
	int err, queue;

	if (pkt_data->flags & IEEE80211_TXPD_REQUEUE) {
	skb_queue_tail(&q->requeued[pkt_data->queue], skb);
	qd->q.qlen++;
	return 0;
	}

	queue = classify80211(skb, qd);

	/* now we know the 1d priority, fill in the QoS header if there is one
	*/
	if (WLAN_FC_IS_QOS_DATA(fc)) {
	u8 *p = skb->data + ieee80211_get_hdrlen(fc) - 2;
	u8 qos_hdr = skb->priority & QOS_CONTROL_TAG1D_MASK;
	if (local->wifi_wme_noack_test)
	qos_hdr \|= QOS_CONTROL_ACK_POLICY_NOACK <<
	QOS_CONTROL_ACK_POLICY_SHIFT;
	/* qos header is 2 bytes, second reserved */
	*p = qos_hdr;
	p++;
	*p = 0;
	}

	if (unlikely(queue >= local->hw.queues)) {
	#if 0
	if (net_ratelimit()) {
	printk(KERN_DEBUG "%s - queue=%d (hw does not "
	"support) -> %d\n",
	__func__, queue, local->hw.queues - 1);
	}
	#endif
	queue = local->hw.queues - 1;
	}

	if (unlikely(queue < 0)) {
	kfree_skb(skb);
	err = NET_XMIT_DROP;
	} else {
	pkt_data->queue = (unsigned int) queue;
	qdisc = q->queues[queue];
	err = qdisc->enqueue(skb, qdisc);
	if (err == NET_XMIT_SUCCESS) {
	qd->q.qlen++;
	qd->bstats.bytes += skb->len;
	qd->bstats.packets++;
	return NET_XMIT_SUCCESS;
	}
	}
	qd->qstats.drops++;
	return err;
	}


	/* TODO: clean up the cases where master_hard_start_xmit
	* returns non 0 - it shouldn't ever do that. Once done we
	* can remove this function */
	static int wme_qdiscop_requeue(struct sk_buff skb, struct Qdisc qd)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_tx_packet_data *pkt_data =
	(struct ieee80211_tx_packet_data *) skb->cb;
	struct Qdisc *qdisc;
	int err;

	/* we recorded which queue to use earlier! */
	qdisc = q->queues[pkt_data->queue];

	if ((err = qdisc->ops->requeue(skb, qdisc)) == 0) {
	qd->q.qlen++;
	return 0;
	}
	qd->qstats.drops++;
	return err;
	}


	static struct sk_buff wme_qdiscop_dequeue(struct Qdisc qd)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct net_device *dev = qd->dev;
	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	struct sk_buff *skb;
	struct Qdisc *qdisc;
	int queue;

	/* check all the h/w queues in numeric/priority order */
	for (queue = 0; queue < hw->queues; queue++) {
	/* see if there is room in this hardware queue */
	if (test_bit(IEEE80211_LINK_STATE_XOFF,
	&local->state[queue]) \|\|
	test_bit(IEEE80211_LINK_STATE_PENDING,
	&local->state[queue]))
	continue;

	/* there is space - try and get a frame */
	skb = skb_dequeue(&q->requeued[queue]);
	if (skb) {
	qd->q.qlen--;
	return skb;
	}

	qdisc = q->queues[queue];
	skb = qdisc->dequeue(qdisc);
	if (skb) {
	qd->q.qlen--;
	return skb;
	}
	}
	/* returning a NULL here when all the h/w queues are full means we
	* never need to call netif_stop_queue in the driver */
	return NULL;
	}


	static void wme_qdiscop_reset(struct Qdisc* qd)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	int queue;

	/* QUESTION: should we have some hardware flush functionality here? */

	for (queue = 0; queue < hw->queues; queue++) {
	skb_queue_purge(&q->requeued[queue]);
	qdisc_reset(q->queues[queue]);
	}
	qd->q.qlen = 0;
	}


	static void wme_qdiscop_destroy(struct Qdisc* qd)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	int queue;

	tcf_destroy_chain(q->filter_list);
	q->filter_list = NULL;

	for (queue=0; queue < hw->queues; queue++) {
	skb_queue_purge(&q->requeued[queue]);
	qdisc_destroy(q->queues[queue]);
	q->queues[queue] = &noop_qdisc;
	}
	}


	/* called whenever parameters are updated on existing qdisc */
	static int wme_qdiscop_tune(struct Qdisc qd, struct rtattr opt)
	{
	/* struct ieee80211_sched_data *q = qdisc_priv(qd);
	*/
	/* check our options block is the right size */
	/* copy any options to our local structure */
	/* Ignore options block for now - always use static mapping
	struct tc_ieee80211_qopt *qopt = RTA_DATA(opt);

	if (opt->rta_len < RTA_LENGTH(sizeof(*qopt)))
	return -EINVAL;
	memcpy(q->tag2queue, qopt->tag2queue, sizeof(qopt->tag2queue));
	*/
	return 0;
	}


	/* called during initial creation of qdisc on device */
	static int wme_qdiscop_init(struct Qdisc qd, struct rtattr opt)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct net_device *dev = qd->dev;
	struct ieee80211_local *local;
	int queues;
	int err = 0, i;

	/* check that device is a mac80211 device */
	if (!dev->ieee80211_ptr \|\|
	dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
	return -EINVAL;

	/* check this device is an ieee80211 master type device */
	if (dev->type != ARPHRD_IEEE80211)
	return -EINVAL;

	/* check that there is no qdisc currently attached to device
	* this ensures that we will be the root qdisc. (I can't find a better
	* way to test this explicitly) */
	if (dev->qdisc_sleeping != &noop_qdisc)
	return -EINVAL;

	if (qd->flags & TCQ_F_INGRESS)
	return -EINVAL;

	local = wdev_priv(dev->ieee80211_ptr);
	queues = local->hw.queues;

	/* if options were passed in, set them */
	if (opt) {
	err = wme_qdiscop_tune(qd, opt);
	}

	/* create child queues */
	for (i = 0; i < queues; i++) {
	skb_queue_head_init(&q->requeued[i]);
	q->queues[i] = qdisc_create_dflt(qd->dev, &pfifo_qdisc_ops,
	qd->handle);
	if (!q->queues[i]) {
	q->queues[i] = &noop_qdisc;
	printk(KERN_ERR "%s child qdisc %i creation failed", dev->name, i);
	}
	}

	return err;
	}

	static int wme_qdiscop_dump(struct Qdisc qd, struct sk_buff skb)
	{
	/* struct ieee80211_sched_data *q = qdisc_priv(qd);
	unsigned char *p = skb->tail;
	struct tc_ieee80211_qopt opt;

	memcpy(&opt.tag2queue, q->tag2queue, TC_80211_MAX_TAG + 1);
	RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
	*/ return skb->len;
	/*
	rtattr_failure:
	skb_trim(skb, p - skb->data);*/
	return -1;
	}


	static int wme_classop_graft(struct Qdisc *qd, unsigned long arg,
	struct Qdisc new, struct Qdisc *old)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	unsigned long queue = arg - 1;

	if (queue >= hw->queues)
	return -EINVAL;

	if (!new)
	new = &noop_qdisc;

	sch_tree_lock(qd);
	*old = q->queues[queue];
	q->queues[queue] = new;
	qdisc_reset(*old);
	sch_tree_unlock(qd);

	return 0;
	}


	static struct Qdisc *
	wme_classop_leaf(struct Qdisc *qd, unsigned long arg)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	unsigned long queue = arg - 1;

	if (queue >= hw->queues)
	return NULL;

	return q->queues[queue];
	}


	static unsigned long wme_classop_get(struct Qdisc *qd, u32 classid)
	{
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	unsigned long queue = TC_H_MIN(classid);

	if (queue - 1 >= hw->queues)
	return 0;

	return queue;
	}


	static unsigned long wme_classop_bind(struct Qdisc *qd, unsigned long parent,
	u32 classid)
	{
	return wme_classop_get(qd, classid);
	}


	static void wme_classop_put(struct Qdisc *q, unsigned long cl)
	{
	}


	static int wme_classop_change(struct Qdisc *qd, u32 handle, u32 parent,
	struct rtattr *tca, unsigned long arg)
	{
	unsigned long cl = *arg;
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;

	if (cl - 1 > hw->queues)
	return -ENOENT;

	/* TODO: put code to program hardware queue parameters here,
	* to allow programming from tc command line */

	return 0;
	}


	/* we don't support deleting hardware queues
	* when we add WMM-SA support - TSPECs may be deleted here */
	static int wme_classop_delete(struct Qdisc *qd, unsigned long cl)
	{
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;

	if (cl - 1 > hw->queues)
	return -ENOENT;
	return 0;
	}


	static int wme_classop_dump_class(struct Qdisc *qd, unsigned long cl,
	struct sk_buff skb, struct tcmsg tcm)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;

	if (cl - 1 > hw->queues)
	return -ENOENT;
	tcm->tcm_handle = TC_H_MIN(cl);
	tcm->tcm_parent = qd->handle;
	tcm->tcm_info = q->queues[cl-1]->handle; /* do we need this? */
	return 0;
	}


	static void wme_classop_walk(struct Qdisc qd, struct qdisc_walker arg)
	{
	struct ieee80211_local *local = wdev_priv(qd->dev->ieee80211_ptr);
	struct ieee80211_hw *hw = &local->hw;
	int queue;

	if (arg->stop)
	return;

	for (queue = 0; queue < hw->queues; queue++) {
	if (arg->count < arg->skip) {
	arg->count++;
	continue;
	}
	/* we should return classids for our internal queues here
	* as well as the external ones */
	if (arg->fn(qd, queue+1, arg) < 0) {
	arg->stop = 1;
	break;
	}
	arg->count++;
	}
	}


	static struct tcf_proto ** wme_classop_find_tcf(struct Qdisc *qd,
	unsigned long cl)
	{
	struct ieee80211_sched_data *q = qdisc_priv(qd);

	if (cl)
	return NULL;

	return &q->filter_list;
	}


	/* this qdisc is classful (i.e. has classes, some of which may have leaf qdiscs attached)
	* - these are the operations on the classes */
	static const struct Qdisc_class_ops class_ops =
	{
	.graft = wme_classop_graft,
	.leaf = wme_classop_leaf,

	.get = wme_classop_get,
	.put = wme_classop_put,
	.change = wme_classop_change,
	.delete = wme_classop_delete,
	.walk = wme_classop_walk,

	.tcf_chain = wme_classop_find_tcf,
	.bind_tcf = wme_classop_bind,
	.unbind_tcf = wme_classop_put,

	.dump = wme_classop_dump_class,
	};


	/* queueing discipline operations */
	static struct Qdisc_ops wme_qdisc_ops __read_mostly =
	{
	.next = NULL,
	.cl_ops = &class_ops,
	.id = "ieee80211",
	.priv_size = sizeof(struct ieee80211_sched_data),

	.enqueue = wme_qdiscop_enqueue,
	.dequeue = wme_qdiscop_dequeue,
	.requeue = wme_qdiscop_requeue,
	.drop = NULL, /* drop not needed since we are always the root qdisc */

	.init = wme_qdiscop_init,
	.reset = wme_qdiscop_reset,
	.destroy = wme_qdiscop_destroy,
	.change = wme_qdiscop_tune,

	.dump = wme_qdiscop_dump,
	};


	void ieee80211_install_qdisc(struct net_device *dev)
	{
	struct Qdisc *qdisc;

	qdisc = qdisc_create_dflt(dev, &wme_qdisc_ops, TC_H_ROOT);
	if (!qdisc) {
	printk(KERN_ERR "%s: qdisc installation failed\n", dev->name);
	return;
	}

	/* same handle as would be allocated by qdisc_alloc_handle() */
	qdisc->handle = 0x80010000;

	qdisc_lock_tree(dev);
	list_add_tail(&qdisc->list, &dev->qdisc_list);
	dev->qdisc_sleeping = qdisc;
	qdisc_unlock_tree(dev);
	}


	int ieee80211_qdisc_installed(struct net_device *dev)
	{
	return dev->qdisc_sleeping->ops == &wme_qdisc_ops;
	}


	int ieee80211_wme_register(void)
	{
	return register_qdisc(&wme_qdisc_ops);
	}


	void ieee80211_wme_unregister(void)
	{
	unregister_qdisc(&wme_qdisc_ops);
	}