| Message ID | 1404995261-6626-1-git-send-email-rostislav.lisovy@fel.cvut.cz (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Thu, 2014-07-10 at 14:27 +0200, Rostislav Lisovy wrote: > Add support for parsing radiotap field IEEE80211_RADIOTAP_RATE > for transmitted frames. Use the provided datarate value in > info->control.rates[] array so it will be used for transmission. > > Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz> > --- > This feature is essential for Transmit Datarate Control (TDC) > in future implementation of IEEE 802.11-2012 "Wireless Access > for the Vehicular Environment" support. It seems like an extremely bad idea to base your implementation of WAVE on monitor mode with injection. Why can't you add a proper datapath? johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 2014-07-21 at 12:20 +0200, Johannes Berg wrote: > On Thu, 2014-07-10 at 14:27 +0200, Rostislav Lisovy wrote: > > Add support for parsing radiotap field IEEE80211_RADIOTAP_RATE > > for transmitted frames. Use the provided datarate value in > > info->control.rates[] array so it will be used for transmission. > > > > Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz> > > --- > > This feature is essential for Transmit Datarate Control (TDC) > > in future implementation of IEEE 802.11-2012 "Wireless Access > > for the Vehicular Environment" support. > > It seems like an extremely bad idea to base your implementation of WAVE > on monitor mode with injection. > > Why can't you add a proper datapath? > You are right. I was overthinking the per-packet datarate setting a little bit. If I am not mistaken it is not possible to say that this feature may be useful as the general method for monitor-mode injection with datarate until there is some user-space utility really using/needing it? Best regards; Rostislav -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 2014-08-25 at 09:52 +0200, Rostislav Lisovy wrote: > If I am not mistaken it is not possible to say that this feature may be > useful as the general method for monitor-mode injection with datarate > until there is some user-space utility really using/needing it? Yes, this wasn't as much a comment on the patch as rather on your implied approach for your userspace :) That said, it's tricky, be cause much hardware doesn't allow to do this. Maybe we should then have a feature flag or so rather than silently ignoring the data? johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 9ce5cb1..7ba8faa 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -549,11 +549,13 @@ enum mac80211_tx_info_flags { * * @IEEE80211_TX_CTRL_PORT_CTRL_PROTO: this frame is a port control * protocol frame (e.g. EAP) + * @IEEE80211_TX_CTRL_USERRATE: Fixed datarate set by the user * * These flags are used in tx_info->control.flags. */ enum mac80211_tx_control_flags { IEEE80211_TX_CTRL_PORT_CTRL_PROTO = BIT(0), + IEEE80211_TX_CTRL_USERRATE = BIT(1), }; /* diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c index 8fdadfd..1111dee 100644 --- a/net/mac80211/rate.c +++ b/net/mac80211/rate.c @@ -673,6 +673,10 @@ void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, priv_sta = sta->rate_ctrl_priv; } + if ((info->flags & IEEE80211_TX_CTL_INJECTED) && + (info->control.flags & IEEE80211_TX_CTRL_USERRATE)) + return; + for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { info->control.rates[i].idx = -1; info->control.rates[i].flags = 0; diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 865bdaf..2099c70 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1541,7 +1541,11 @@ static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb) struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len, NULL); + struct ieee80211_sub_if_data *sdata; + struct ieee80211_supported_band *sband; + int rate; u16 txflags; + int i, j; info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT | IEEE80211_TX_CTL_DONTFRAG; @@ -1592,6 +1596,45 @@ static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb) info->flags |= IEEE80211_TX_CTL_NO_ACK; break; + case IEEE80211_RADIOTAP_RATE: + if (!(*iterator.this_arg)) + break; + + rate = 0; + sdata = vif_to_sdata(info->control.vif); + sband = sdata->wdev.wiphy->bands[info->band]; + for (i = 0; i < sband->n_bitrates; i++) { + /* Radiotap datarate: Units of 500 Kbps + * ieee80211_rate.bitrate: Units of 100 Kbps + */ + if ((sband->bitrates[i].bitrate * 2) == + ((*iterator.this_arg) * 10)) { + rate = i; + break; + } + } + + if (!rate) + break; + + info->flags |= IEEE80211_TX_CTRL_USERRATE; + + for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { + if (info->control.rates[i].idx < 0) + break; + + /* Rate masking supports only legacy + * rates for now + */ + if (info->control.rates[i].flags & + IEEE80211_TX_RC_MCS) + continue; + + for (j = 0; j < sband->n_bitrates; j++) + info->control.rates[i].idx = rate; + } + break; + /* * Please update the file * Documentation/networking/mac80211-injection.txt
Add support for parsing radiotap field IEEE80211_RADIOTAP_RATE for transmitted frames. Use the provided datarate value in info->control.rates[] array so it will be used for transmission. Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz> --- This feature is essential for Transmit Datarate Control (TDC) in future implementation of IEEE 802.11-2012 "Wireless Access for the Vehicular Environment" support. include/net/mac80211.h | 2 ++ net/mac80211/rate.c | 4 ++++ net/mac80211/tx.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+)