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.lis...@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(+)
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
--
2.0.0.rc4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
