mac80211: handle MMPDUs at EOSP correctly

If a uAPSD service period ends with an MMPDU, we currently just
send that MMPDU, but it obviously won't get the EOSP bit set as
it doesn't have a QoS header. This contradicts the standard, so
add a QoS-nulldata frame after the MMPDU to properly terminate
the service period with a frame that has EOSP set.

Also fix a bug wrt. the TID for the MMPDU, it shouldn't be set
to 0 unconditionally but use the actual TID that was assigned.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2014-01-09 00:00:38 +01:00
parent 03c8c06f2d
commit b77cf4f8e1
2 changed files with 64 additions and 15 deletions

View File

@ -2119,6 +2119,11 @@ void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb);
* appropriately (only the last frame may have %IEEE80211_TX_STATUS_EOSP)
* and also take care of the EOSP and MORE_DATA bits in the frame.
* The driver may also use ieee80211_sta_eosp() in this case.
*
* Note that if the driver ever buffers frames other than QoS-data
* frames, it must take care to never send a non-QoS-data frame as
* the last frame in a service period, adding a QoS-nulldata frame
* after a non-QoS-data frame if needed.
*/
/**

View File

@ -1153,7 +1153,8 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
static void ieee80211_send_null_response(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta, int tid,
enum ieee80211_frame_release_type reason)
enum ieee80211_frame_release_type reason,
bool call_driver)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_qos_hdr *nullfunc;
@ -1211,7 +1212,9 @@ static void ieee80211_send_null_response(struct ieee80211_sub_if_data *sdata,
IEEE80211_TX_STATUS_EOSP |
IEEE80211_TX_CTL_REQ_TX_STATUS;
drv_allow_buffered_frames(local, sta, BIT(tid), 1, reason, false);
if (call_driver)
drv_allow_buffered_frames(local, sta, BIT(tid), 1,
reason, false);
skb->dev = sdata->dev;
@ -1334,12 +1337,13 @@ ieee80211_sta_ps_deliver_response(struct sta_info *sta,
/* This will evaluate to 1, 3, 5 or 7. */
tid = 7 - ((ffs(~ignored_acs) - 1) << 1);
ieee80211_send_null_response(sdata, sta, tid, reason);
ieee80211_send_null_response(sdata, sta, tid, reason, true);
} else if (!driver_release_tids) {
struct sk_buff_head pending;
struct sk_buff *skb;
int num = 0;
u16 tids = 0;
bool need_null = false;
skb_queue_head_init(&pending);
@ -1373,22 +1377,57 @@ ieee80211_sta_ps_deliver_response(struct sta_info *sta,
ieee80211_is_qos_nullfunc(hdr->frame_control))
qoshdr = ieee80211_get_qos_ctl(hdr);
/* end service period after last frame */
if (skb_queue_empty(&frames)) {
if (reason == IEEE80211_FRAME_RELEASE_UAPSD &&
qoshdr)
*qoshdr |= IEEE80211_QOS_CTL_EOSP;
tids |= BIT(skb->priority);
__skb_queue_tail(&pending, skb);
/* end service period after last frame or add one */
if (!skb_queue_empty(&frames))
continue;
if (reason != IEEE80211_FRAME_RELEASE_UAPSD) {
/* for PS-Poll, there's only one frame */
info->flags |= IEEE80211_TX_STATUS_EOSP |
IEEE80211_TX_CTL_REQ_TX_STATUS;
break;
}
/* For uAPSD, things are a bit more complicated. If the
* last frame has a QoS header (i.e. is a QoS-data or
* QoS-nulldata frame) then just set the EOSP bit there
* and be done.
* If the frame doesn't have a QoS header (which means
* it should be a bufferable MMPDU) then we can't set
* the EOSP bit in the QoS header; add a QoS-nulldata
* frame to the list to send it after the MMPDU.
*
* Note that this code is only in the mac80211-release
* code path, we assume that the driver will not buffer
* anything but QoS-data frames, or if it does, will
* create the QoS-nulldata frame by itself if needed.
*
* Cf. 802.11-2012 10.2.1.10 (c).
*/
if (qoshdr) {
*qoshdr |= IEEE80211_QOS_CTL_EOSP;
info->flags |= IEEE80211_TX_STATUS_EOSP |
IEEE80211_TX_CTL_REQ_TX_STATUS;
} else {
/* The standard isn't completely clear on this
* as it says the more-data bit should be set
* if there are more BUs. The QoS-Null frame
* we're about to send isn't buffered yet, we
* only create it below, but let's pretend it
* was buffered just in case some clients only
* expect more-data=0 when eosp=1.
*/
hdr->frame_control |=
cpu_to_le16(IEEE80211_FCTL_MOREDATA);
need_null = true;
num++;
}
if (qoshdr)
tids |= BIT(*qoshdr & IEEE80211_QOS_CTL_TID_MASK);
else
tids |= BIT(0);
__skb_queue_tail(&pending, skb);
break;
}
drv_allow_buffered_frames(local, sta, tids, num,
@ -1396,6 +1435,11 @@ ieee80211_sta_ps_deliver_response(struct sta_info *sta,
ieee80211_add_pending_skbs(local, &pending);
if (need_null)
ieee80211_send_null_response(
sdata, sta, find_highest_prio_tid(tids),
reason, false);
sta_info_recalc_tim(sta);
} else {
/*