2009/8/21 Rafael Laufer <rlaufer@xxxxxxxxxxx>:
> Gábor Stefanik wrote:
>>
>> Maybe a new IEEE80211_TX_CTL_ or IEEE80211_TX_RC_ flag will also be
>> needed, so Radiotap can indicate whether rate_control_get_rate needs
>> to be called.
>
> ok, I am resending the patch. I included a new flag called
> IEEE80211_TX_CTL_RATE_RADIOTAP to indicate if the rate has
> been set in the radiotap header. If not, then the rate control
> algorithm is called.
Isn't it easier to check whether we already have a rate configured?
(info->control.rates[0].idx is set to an invalid value before the
rate_control_get_rate call AFAIK, unless you set it in the radiotap
decoding function before.)
>
> Note that in the future there must be other flags like this to
> indicate if other parameters, such as power, was also set in
> the radiotap header.
>
>
> Signed-off-by: Rafael Laufer <rlaufer@xxxxxxxxxxx>
> ---
> Implementation of the IEEE80211_RADIOTAP_RATE
> option when parsing radiotap headers to allow
> rate selection on a per-packet basis. A new
> flag IEEE80211_TX_CTL_RATE_RADIOTAP is also
> included to indicate that the rate was set in
> the radiotap header and therefore the rate
> control algorithm should not change it.
>
> include/net/mac80211.h | 4 ++++
> net/mac80211/tx.c | 22 +++++++++++++++++++++-
> 2 files changed, 25 insertions(+), 1 deletions(-)
>
> diff --git a/include/net/mac80211.h b/include/net/mac80211.h
> index aac84d7..819b01e 100644
> --- a/include/net/mac80211.h
> +++ b/include/net/mac80211.h
> @@ -272,6 +272,9 @@ struct ieee80211_bss_conf {
> * transmit function after the current frame, this can be used
> * by drivers to kick the DMA queue only if unset or when the
> * queue gets full.
> + * @IEEE80211_TX_CTL_RATE_RADIOTAP: completely internal to mac80211,
> + * used to indicate that the rate was defined in the received radiotap
> + * header and therefore the rate control algorithm should not change it.
> */
> enum mac80211_tx_control_flags {
> IEEE80211_TX_CTL_REQ_TX_STATUS = BIT(0),
> @@ -293,6 +296,7 @@ enum mac80211_tx_control_flags {
> IEEE80211_TX_INTFL_DONT_ENCRYPT = BIT(16),
> IEEE80211_TX_CTL_PSPOLL_RESPONSE = BIT(17),
> IEEE80211_TX_CTL_MORE_FRAMES = BIT(18),
> + IEEE80211_TX_CTL_RATE_RADIOTAP = BIT(19),
> };
>
> /**
> diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
> index 10a1099..f675844 100644
> --- a/net/mac80211/tx.c
> +++ b/net/mac80211/tx.c
> @@ -549,7 +549,12 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
> * If we're associated with the sta at this point we know we can at
> * least send the frame at the lowest bit rate.
> */
> - rate_control_get_rate(tx->sdata, tx->sta, &txrc);
> +
> + /* In monitor mode, if the IEEE80211_RADIOTAP_RATE option is set in
> + * the received radiotap header, do not call the rate control algorithm.
> + */
> + if (likely(!(info->flags & IEEE80211_TX_CTL_RATE_RADIOTAP)))
> + rate_control_get_rate(tx->sdata, tx->sta, &txrc);
>
> if (unlikely(info->control.rates[0].idx < 0))
> return TX_DROP;
> @@ -972,6 +977,21 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx,
> tx->flags |= IEEE80211_TX_FRAGMENTED;
> break;
>
> + /* Get the rate parameter from the radiotap header,
> + * allowing rate selection on a per-packet basis
> + */
> + case IEEE80211_RADIOTAP_RATE:
> + bitrate = (*iterator.this_arg) * 5;
> + for (i = 0; i < sband->n_bitrates; i++) {
> + if (sband->bitrates[i].bitrate == bitrate)
> + break;
> + }
> + if (i != sband->n_bitrates) {
> + info->control.rates[0].idx = i;
> + info->flags |= IEEE80211_TX_CTL_RATE_RADIOTAP;
> + }
> + break;
> +
> /*
> * Please update the file
> * Documentation/networking/mac80211-injection.txt
> --
> 1.6.0.4
>
>
--
Vista: [V]iruses, [I]ntruders, [S]pyware, [T]rojans and [A]dware. :-)
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