Re: [PATCH] ath9k_hw: Abort transmission for sleeping station

[Felix Fietkau <nbd@openwrt.org>]

On 2014-05-20 09:00, Felix Fietkau wrote:
> On 2014-05-19 08:14, Rajkumar Manoharan wrote:
>> The data transmission to the power save station should be aborted
>> immediately, whenever the station informs sleep state. Right now
>> the frames queued into into hardware are being transmitted until
>> the hardware detects the power save station based excessive retries
>> of the data frames due to unacknowlegdement. Then remaining frames
>> are returned with filetered status and might be retried later by
>> driver or mac80211.
>> 
>> Per WFA certification testing, AP should not send out more than two
>> frames after processing nullfunc with PM bit set from associated
>> station. To speed up tx filtering, the pending frames in hardware
>> queues for given station will be aborted immediately via tx filter
>> registers. This transmit filters can be ignored if the descriptor
>> is having invalid destination index or clear destination mask set.
>> 
>> Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
>> ---
>>  drivers/net/wireless/ath/ath9k/mac.c  | 22 ++++++++++++++++++++++
>>  drivers/net/wireless/ath/ath9k/mac.h  |  1 +
>>  drivers/net/wireless/ath/ath9k/main.c |  8 ++++++++
>>  drivers/net/wireless/ath/ath9k/reg.h  |  3 ---
>>  4 files changed, 31 insertions(+), 3 deletions(-)
>> 
>> diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
>> index 8d7b9b6..47d442a 100644
>> --- a/drivers/net/wireless/ath/ath9k/main.c
>> +++ b/drivers/net/wireless/ath/ath9k/main.c
> 
>> @@ -1593,6 +1597,8 @@ static int ath9k_set_key(struct ieee80211_hw *hw,
>>  			ath9k_del_ps_key(sc, vif, sta);
>>  
>>  		ret = ath_key_config(common, vif, sta, key);
>> +		if (sta && (ret > 0))
>> +			((struct ath_node *)sta->drv_priv)->ps_key = ret;
>>  		if (ret >= 0) {
>>  			key->hw_key_idx = ret;
>>  			/* push IV and Michael MIC generation to stack */
>> @@ -1607,6 +1613,8 @@ static int ath9k_set_key(struct ieee80211_hw *hw,
>>  		break;
>>  	case DISABLE_KEY:
>>  		ath_key_delete(common, key);
>> +		if (sta)
>> +			((struct ath_node *)sta->drv_priv)->ps_key = 0;
>>  		break;
>>  	default:
>>  		ret = -EINVAL;
> I think this part won't work if you have multiple keys for the same STA.
> Also, it will leak the previous ps_key if it was auto-assigned for an
> unencrypted sta.
Actually, never mind about the leak, ath9k_del_ps_key will take care of
that. Having multiple keys will still be problematic though.

- Felix