2010-09-16 08:34:16

by Bruno Randolf

Subject: [PATCH] mac80211: Add WME information element for IBSS

Enable WME QoS in IBSS mode by adding a WME information element to beacons and
probe respones and by checking for it and marking stations as WME capable if it
is present.

Signed-off-by: Bruno Randolf <[email protected]>
---
net/mac80211/ibss.c | 20 ++++++++++++++++++--
1 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 1a3aae5..95fe43f 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -173,6 +173,19 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
memcpy(skb_put(skb, ifibss->ie_len),
ifibss->ie, ifibss->ie_len);

+ if (local->hw.queues >= 4) {
+ pos = skb_put(skb, 9);
+ *pos++ = WLAN_EID_VENDOR_SPECIFIC;
+ *pos++ = 7; /* len */
+ *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
+ *pos++ = 0x50;
+ *pos++ = 0xf2;
+ *pos++ = 2; /* WME */
+ *pos++ = 0; /* WME info */
+ *pos++ = 1; /* WME ver */
+ *pos++ = 0; /* U-APSD no in use */
+ }
+
rcu_assign_pointer(ifibss->presp, skb);

sdata->vif.bss_conf.beacon_int = beacon_int;
@@ -294,9 +307,12 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
rcu_read_unlock();
} else {
rcu_read_unlock();
- ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
- supp_rates, GFP_KERNEL);
+
+ sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
+ mgmt->sa, supp_rates, GFP_KERNEL);
}
+ if (sta && elems->wmm_info)
+ set_sta_flags(sta, WLAN_STA_WME);
}

bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,

2010-09-16 09:38:36

by Johannes Berg

Subject: Re: [PATCH] mac80211: Add WME information element for IBSS

On Thu, 2010-09-16 at 17:34 +0900, Bruno Randolf wrote:
> Enable WME QoS in IBSS mode by adding a WME information element to beacons and
> probe respones and by checking for it and marking stations as WME capable if it
> is present.

> rcu_read_unlock();
> - ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
> - supp_rates, GFP_KERNEL);
> +
> + sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
> + mgmt->sa, supp_rates, GFP_KERNEL);
> }
> + if (sta && elems->wmm_info)
> + set_sta_flags(sta, WLAN_STA_WME);

NACK, this is obviously racy.

johannes

2010-10-01 08:13:57

by Johannes Berg

Subject: Re: [PATCH] mac80211: Add WME information element for IBSS

On Fri, 2010-10-01 at 14:15 +0900, Bruno Randolf wrote:

> + if (elems->wmm_info)
> + set_sta_flags(sta, WLAN_STA_WME);
> rcu_read_unlock();
> } else {
> rcu_read_unlock();
> - ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
> - supp_rates, GFP_KERNEL);
> +
> + sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
> + mgmt->sa, supp_rates, GFP_KERNEL);
> + if (sta && elems->wmm_info)
> + set_sta_flags(sta, WLAN_STA_WME);

If you want to use the sta pointer, you need this code to be before
rcu_read_unlock(), not after.

johannes

2010-10-01 05:15:57

by Bruno Randolf

Subject: Re: [PATCH] mac80211: Add WME information element for IBSS

On Thu September 16 2010 18:37:33 Johannes Berg wrote:
> On Thu, 2010-09-16 at 17:34 +0900, Bruno Randolf wrote:
> > Enable WME QoS in IBSS mode by adding a WME information element to
> > beacons and probe respones and by checking for it and marking stations
> > as WME capable if it is present.
> >
> > rcu_read_unlock();
> >
> > - ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
> > - supp_rates, GFP_KERNEL);
> > +
> > + sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
> > + mgmt->sa, supp_rates, GFP_KERNEL);
> >
> > }
> >
> > + if (sta && elems->wmm_info)
> > + set_sta_flags(sta, WLAN_STA_WME);
>
> NACK, this is obviously racy.

sorry for the late reply.

better like this?

@@ -291,11 +304,16 @@ static void ieee80211_rx_bss_info(struct
ieee80211_sub_if_data *sdata,
#endif
rate_control_rate_init(sta);
}
+ if (elems->wmm_info)
+ set_sta_flags(sta, WLAN_STA_WME);
rcu_read_unlock();
} else {
rcu_read_unlock();
- ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
- supp_rates, GFP_KERNEL);
+
+ sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
+ mgmt->sa, supp_rates, GFP_KERNEL);
+ if (sta && elems->wmm_info)
+ set_sta_flags(sta, WLAN_STA_WME);
}
}

if not, i don't get it... could you explain how it should be done properly?

thanks,
bruno