[PATCH 1/2] cfg80211: add support for setting the ad-hoc multicast rate

[PATCH 1/2] cfg80211: add support for setting the ad-hoc multicast rate

[Felix Fietkau]

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
 include/linux/nl80211.h |    4 ++++
 include/net/cfg80211.h  |    2 ++
 net/wireless/nl80211.c  |    4 ++++
 3 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index fb877b5..9ee61fa 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -804,6 +804,8 @@ enum nl80211_commands {
  * @NL80211_ATTR_SUPPORT_IBSS_RSN: The device supports IBSS RSN, which mostly
  *	means support for per-station GTKs.
  *
+ * @NL80211_ATTR_MCAST_RATE: Multicast tx rate (in 100 kbps) for IBSS
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -973,6 +975,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_SUPPORT_IBSS_RSN,
 
+	NL80211_ATTR_MCAST_RATE,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index e5702f5..15cc593 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -923,6 +923,7 @@ struct cfg80211_disassoc_request {
  * @privacy: this is a protected network, keys will be configured
  *	after joining
  * @basic_rates: bitmap of basic rates to use when creating the IBSS
+ * @mcast_rate: multicast tx rate (in 100 kbps)
  */
 struct cfg80211_ibss_params {
 	u8 *ssid;
@@ -934,6 +935,7 @@ struct cfg80211_ibss_params {
 	u32 basic_rates;
 	bool channel_fixed;
 	bool privacy;
+	int mcast_rate;
 };
 
 /**
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 4e78e3f..b3da2e0 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -167,6 +167,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 	[NL80211_ATTR_WIPHY_TX_POWER_SETTING] = { .type = NLA_U32 },
 	[NL80211_ATTR_WIPHY_TX_POWER_LEVEL] = { .type = NLA_U32 },
 	[NL80211_ATTR_FRAME_TYPE] = { .type = NLA_U16 },
+	[NL80211_ATTR_MCAST_RATE] = { .type = NLA_U32 },
 };
 
 /* policy for the key attributes */
@@ -3652,6 +3653,9 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
 				return -EINVAL;
 		}
 	}
+	if (info->attrs[NL80211_ATTR_MCAST_RATE])
+		ibss.mcast_rate =
+			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);
 
 	if (ibss.privacy && info->attrs[NL80211_ATTR_KEYS]) {
 		connkeys = nl80211_parse_connkeys(rdev,
-- 
1.7.2.2

[PATCH 2/2] mac80211: add support for setting the ad-hoc multicast rate

[Felix Fietkau]

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
 include/net/mac80211.h |    6 ++++--
 net/mac80211/ibss.c    |    1 +
 net/mac80211/rate.c    |   19 +++++++++++++++----
 net/mac80211/tx.c      |    5 +++--
 4 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 9fdf982..e4d173e 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -205,6 +205,7 @@ enum ieee80211_bss_change {
  * @basic_rates: bitmap of basic rates, each bit stands for an
  *	index into the rate table configured by the driver in
  *	the current band.
+ * @mcast_rate: multicast rate for AP and Ad-Hoc (in 100 kbps)
  * @bssid: The BSSID for this BSS
  * @enable_beacon: whether beaconing should be enabled or not
  * @channel_type: Channel type for this BSS -- the hardware might be
@@ -244,6 +245,7 @@ struct ieee80211_bss_conf {
 	u16 assoc_capability;
 	u64 timestamp;
 	u32 basic_rates;
+	u32 mcast_rate;
 	u16 ht_operation_mode;
 	s32 cqm_rssi_thold;
 	u32 cqm_rssi_hyst;
@@ -2640,7 +2642,7 @@ enum rate_control_changed {
  * @rate_idx_mask: user-requested rate mask (not MCS for now)
  * @skb: the skb that will be transmitted, the control information in it needs
  *	to be filled in
- * @ap: whether this frame is sent out in AP mode
+ * @bss: whether this frame is sent out in AP or IBSS mode
  */
 struct ieee80211_tx_rate_control {
 	struct ieee80211_hw *hw;
@@ -2651,7 +2653,7 @@ struct ieee80211_tx_rate_control {
 	bool rts, short_preamble;
 	u8 max_rate_idx;
 	u32 rate_idx_mask;
-	bool ap;
+	bool bss;
 };
 
 struct rate_control_ops {
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 239c483..6fe6837 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -915,6 +915,7 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 
 	sdata->u.ibss.privacy = params->privacy;
 	sdata->u.ibss.basic_rates = params->basic_rates;
+	sdata->vif.bss_conf.mcast_rate = params->mcast_rate;
 
 	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
 
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 33f7699..76de4f8 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -211,10 +211,20 @@ static bool rc_no_data_or_no_ack(struct ieee80211_tx_rate_control *txrc)
 	return (info->flags & IEEE80211_TX_CTL_NO_ACK) || !ieee80211_is_data(fc);
 }
 
-static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u8 max_rate_idx)
+static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u32 mcast_rate,
+				  struct ieee80211_supported_band *sband)
 {
 	u8 i;
 
+	if (mcast_rate) {
+		for (i = 0; i < sband->n_bitrates; i++) {
+			if (sband->bitrates[i].bitrate == mcast_rate) {
+				*idx = i;
+				return;
+			}
+		}
+	}
+
 	if (basic_rates == 0)
 		return; /* assume basic rates unknown and accept rate */
 	if (*idx < 0)
@@ -222,7 +232,7 @@ static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u8 max_rate_idx)
 	if (basic_rates & (1 << *idx))
 		return; /* selected rate is a basic rate */
 
-	for (i = *idx + 1; i <= max_rate_idx; i++) {
+	for (i = *idx + 1; i <= sband->n_bitrates; i++) {
 		if (basic_rates & (1 << i)) {
 			*idx = i;
 			return;
@@ -243,10 +253,11 @@ bool rate_control_send_low(struct ieee80211_sta *sta,
 		info->control.rates[0].count =
 			(info->flags & IEEE80211_TX_CTL_NO_ACK) ?
 			1 : txrc->hw->max_rate_tries;
-		if (!sta && txrc->ap)
+		if (!sta && txrc->bss)
 			rc_send_low_broadcast(&info->control.rates[0].idx,
 					      txrc->bss_conf->basic_rates,
-					      txrc->sband->n_bitrates);
+					      txrc->bss_conf->mcast_rate,
+					      txrc->sband);
 		return true;
 	}
 	return false;
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 96c5943..87ba4ef 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -622,7 +622,8 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
 		txrc.max_rate_idx = -1;
 	else
 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
-	txrc.ap = tx->sdata->vif.type == NL80211_IFTYPE_AP;
+	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
+		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
 
 	/* set up RTS protection if desired */
 	if (len > tx->local->hw.wiphy->rts_threshold) {
@@ -2301,7 +2302,7 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 		txrc.max_rate_idx = -1;
 	else
 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
-	txrc.ap = true;
+	txrc.bss = true;
 	rate_control_get_rate(sdata, NULL, &txrc);
 
 	info->control.vif = vif;
-- 
1.7.2.2

Re: [PATCH 2/2] mac80211: add support for setting the ad-hoc multicast rate

[Johannes Berg]

On Thu, 2010-11-11 at 15:07 +0100, Felix Fietkau wrote:

> +	if (mcast_rate) {
> +		for (i = 0; i < sband->n_bitrates; i++) {
> +			if (sband->bitrates[i].bitrate == mcast_rate) {
> +				*idx = i;
> +				return;
> +			}
> +		}
> +	}

That conversion loop really shouldn't be in the hotpath.

johannes

Re: [PATCH 2/2] mac80211: add support for setting the ad-hoc multicast rate

[Felix Fietkau]

On 2010-11-16 11:27 PM, Johannes Berg wrote:
> On Thu, 2010-11-11 at 15:07 +0100, Felix Fietkau wrote:
> 
>> +	if (mcast_rate) {
>> +		for (i = 0; i < sband->n_bitrates; i++) {
>> +			if (sband->bitrates[i].bitrate == mcast_rate) {
>> +				*idx = i;
>> +				return;
>> +			}
>> +		}
>> +	}
> 
> That conversion loop really shouldn't be in the hotpath.
Seems like the change got merged already, I'll send follow-up fixes soon.

- Felix

Re: [PATCH 1/2] cfg80211: add support for setting the ad-hoc multicast rate

[Johannes Berg]

On Thu, 2010-11-11 at 15:07 +0100, Felix Fietkau wrote:

> +	if (info->attrs[NL80211_ATTR_MCAST_RATE])
> +		ibss.mcast_rate =
> +			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);

That should really check that the rate is supported, and maybe that it's
a basic rate.

johannes

Re: [PATCH 1/2] cfg80211: add support for setting the ad-hoc multicast rate

[Felix Fietkau]

On 2010-11-16 11:27 PM, Johannes Berg wrote:
> On Thu, 2010-11-11 at 15:07 +0100, Felix Fietkau wrote:
> 
>> +	if (info->attrs[NL80211_ATTR_MCAST_RATE])
>> +		ibss.mcast_rate =
>> +			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);
> 
> That should really check that the rate is supported, and maybe that it's
> a basic rate.
But what about band changes then?

- Felix

Re: [PATCH 1/2] cfg80211: add support for setting the ad-hoc multicast rate

[Johannes Berg]

On Wed, 2010-11-17 at 00:34 +0100, Felix Fietkau wrote:
> On 2010-11-16 11:27 PM, Johannes Berg wrote:
> > On Thu, 2010-11-11 at 15:07 +0100, Felix Fietkau wrote:
> > 
> >> +	if (info->attrs[NL80211_ATTR_MCAST_RATE])
> >> +		ibss.mcast_rate =
> >> +			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);
> > 
> > That should really check that the rate is supported, and maybe that it's
> > a basic rate.

> But what about band changes then?

Yeah but what about them? You don't handle them anyway -- should maybe
do a per-band setting? Basically right now you end up ignoring the rate
if it's not available.

johannes