linux/net/mac80211/wme.c
Johannes Berg c2c98fdeb5 mac80211: optimise station flags
The flaglock in struct sta_info has long been
something that I wanted to get rid of, this
finally does the conversion to atomic bitops.

The conversion itself is straight-forward in
most places, a few things needed to change a
bit since we can no longer use multiple bits
at the same time.

On x86-64, this is a fairly significant code
size reduction:
   text	   data	    bss	    dec	    hex
 427861	  23648	   1008	 452517	  6e7a5	before
 425383	  23648	    976	 450007	  6ddd7	after

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-30 15:57:19 -04:00

158 lines
3.6 KiB
C

/*
* 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"
/* Default mapping in classifier to work with default
* queue setup.
*/
const int ieee802_1d_to_ac[8] = {
IEEE80211_AC_BE,
IEEE80211_AC_BK,
IEEE80211_AC_BK,
IEEE80211_AC_BE,
IEEE80211_AC_VI,
IEEE80211_AC_VI,
IEEE80211_AC_VO,
IEEE80211_AC_VO
};
static 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;
}
}
/* Indicate which queue to use. */
u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_local *local = sdata->local;
struct sta_info *sta = NULL;
const u8 *ra = NULL;
bool qos = false;
if (local->hw.queues < 4 || skb->len < 6) {
skb->priority = 0; /* required for correct WPA/11i MIC */
return min_t(u16, local->hw.queues - 1, IEEE80211_AC_BE);
}
rcu_read_lock();
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
sta = rcu_dereference(sdata->u.vlan.sta);
if (sta) {
qos = test_sta_flag(sta, WLAN_STA_WME);
break;
}
case NL80211_IFTYPE_AP:
ra = skb->data;
break;
case NL80211_IFTYPE_WDS:
ra = sdata->u.wds.remote_addr;
break;
#ifdef CONFIG_MAC80211_MESH
case NL80211_IFTYPE_MESH_POINT:
ra = skb->data;
break;
#endif
case NL80211_IFTYPE_STATION:
ra = sdata->u.mgd.bssid;
break;
case NL80211_IFTYPE_ADHOC:
ra = skb->data;
break;
default:
break;
}
if (!sta && ra && !is_multicast_ether_addr(ra)) {
sta = sta_info_get(sdata, ra);
if (sta)
qos = test_sta_flag(sta, WLAN_STA_WME);
}
rcu_read_unlock();
if (!qos) {
skb->priority = 0; /* required for correct WPA/11i MIC */
return IEEE80211_AC_BE;
}
/* use the data classifier to determine what 802.1d tag the
* data frame has */
skb->priority = cfg80211_classify8021d(skb);
return ieee80211_downgrade_queue(local, skb);
}
u16 ieee80211_downgrade_queue(struct ieee80211_local *local,
struct sk_buff *skb)
{
/* 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)) {
/*
* This should not really happen. The AP has marked all
* lower ACs to require admission control which is not
* a reasonable configuration. Allow the frame to be
* transmitted using AC_BK as a workaround.
*/
break;
}
}
/* look up which queue to use for frames with this 1d tag */
return ieee802_1d_to_ac[skb->priority];
}
void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_hdr *hdr = (void *)skb->data;
/* Fill in the QoS header if there is one. */
if (ieee80211_is_data_qos(hdr->frame_control)) {
u8 *p = ieee80211_get_qos_ctl(hdr);
u8 ack_policy = 0, tid;
tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
if (unlikely(sdata->local->wifi_wme_noack_test))
ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
/* qos header is 2 bytes */
*p++ = ack_policy | tid;
*p = ieee80211_vif_is_mesh(&sdata->vif) ?
(IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8) : 0;
}
}