wifi: mac80211: simplify adding supported rates

Make this a new-style "put" function, and change the
parameters to pass more information directly, this
makes it usable also for the MLME code.

Link: https://msgid.link/20240129202041.f604a03bd728.I8c798ea45b8479ac9982e77d0378af11a09ccdaf@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/ieee80211_i.h

@@ -2511,12 +2511,6 @@ u8 *ieee80211_ie_build_eht_oper(u8 *pos, struct cfg80211_chan_def *chandef,
 int ieee80211_parse_bitrates(enum nl80211_chan_width width,
 			     const struct ieee80211_supported_band *sband,
 			     const u8 *srates, int srates_len, u32 *rates);
-int ieee80211_add_srates_ie(struct ieee80211_sub_if_data *sdata,
-			    struct sk_buff *skb, bool need_basic,
-			    enum nl80211_band band);
-int ieee80211_add_ext_srates_ie(struct ieee80211_sub_if_data *sdata,
-				struct sk_buff *skb, bool need_basic,
-				enum nl80211_band band);
 u8 *ieee80211_add_wmm_info_ie(u8 *buf, u8 qosinfo);
 void ieee80211_add_s1g_capab_ie(struct ieee80211_sub_if_data *sdata,
 				struct ieee80211_sta_s1g_cap *caps,
@@ -2526,6 +2520,10 @@ void ieee80211_add_aid_request_ie(struct ieee80211_sub_if_data *sdata,
 u8 *ieee80211_ie_build_s1g_cap(u8 *pos, struct ieee80211_sta_s1g_cap *s1g_cap);
 
 /* element building in SKBs */
+int ieee80211_put_srates_elem(struct sk_buff *skb,
+			      const struct ieee80211_supported_band *sband,
+			      u32 basic_rates, u32 rate_flags, u32 masked_rates,
+			      u8 element_id);
 void ieee80211_put_he_6ghz_cap(struct sk_buff *skb,
 			       struct ieee80211_sub_if_data *sdata,
 			       enum ieee80211_smps_mode smps_mode);

net/mac80211/mesh.c

@@ -968,19 +968,19 @@ ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 	int head_len, tail_len;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	struct ieee80211_chanctx_conf *chanctx_conf;
 	struct mesh_csa_settings *csa;
-	enum nl80211_band band;
+	const struct ieee80211_supported_band *sband;
 	u8 ie_len_he_cap, ie_len_eht_cap;
 	u8 *pos;
 	struct ieee80211_sub_if_data *sdata;
 	int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
+	u32 rate_flags;
 
 	sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
-	rcu_read_lock();
-	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
-	band = chanctx_conf->def.chan->band;
-	rcu_read_unlock();
+
+	sband = ieee80211_get_sband(sdata);
+	rate_flags =
+		ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
 
 	ie_len_he_cap = ieee80211_ie_len_he_cap(sdata);
 	ie_len_eht_cap = ieee80211_ie_len_eht_cap(sdata);
@@ -1107,7 +1107,9 @@ ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 	}
 	rcu_read_unlock();
 
-	if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
+	if (ieee80211_put_srates_elem(skb, sband,
+				      sdata->vif.bss_conf.basic_rates,
+				      rate_flags, 0, WLAN_EID_SUPP_RATES) ||
 	    mesh_add_ds_params_ie(sdata, skb))
 		goto out_free;
 
@@ -1118,7 +1120,9 @@ ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
 	skb_trim(skb, 0);
 	bcn->tail = bcn->head + bcn->head_len;
 
-	if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
+	if (ieee80211_put_srates_elem(skb, sband,
+				      sdata->vif.bss_conf.basic_rates,
+				      rate_flags, 0, WLAN_EID_EXT_SUPP_RATES) ||
 	    mesh_add_rsn_ie(sdata, skb) ||
 	    mesh_add_ht_cap_ie(sdata, skb) ||
 	    mesh_add_ht_oper_ie(sdata, skb) ||

net/mac80211/mesh_plink.c

@@ -264,14 +264,13 @@ static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 
 	if (action != WLAN_SP_MESH_PEERING_CLOSE) {
 		struct ieee80211_supported_band *sband;
-		enum nl80211_band band;
+		u32 rate_flags, basic_rates;
 
 		sband = ieee80211_get_sband(sdata);
 		if (!sband) {
 			err = -EINVAL;
 			goto free;
 		}
-		band = sband->band;
 
 		/* capability info */
 		pos = skb_put_zero(skb, 2);
@@ -280,8 +279,17 @@ static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata,
 			pos = skb_put(skb, 2);
 			put_unaligned_le16(sta->sta.aid, pos);
 		}
-		if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
-		    ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
+
+		rate_flags =
+			ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
+		basic_rates = sdata->vif.bss_conf.basic_rates;
+
+		if (ieee80211_put_srates_elem(skb, sband, basic_rates,
+					      rate_flags, 0,
+					      WLAN_EID_SUPP_RATES) ||
+		    ieee80211_put_srates_elem(skb, sband, basic_rates,
+					      rate_flags, 0,
+					      WLAN_EID_EXT_SUPP_RATES) ||
 		    mesh_add_rsn_ie(sdata, skb) ||
 		    mesh_add_meshid_ie(sdata, skb) ||
 		    mesh_add_meshconf_ie(sdata, skb))

net/mac80211/mlme.c

@@ -1110,10 +1110,7 @@ static void ieee80211_assoc_add_rates(struct sk_buff *skb,
 				      struct ieee80211_supported_band *sband,
 				      struct ieee80211_mgd_assoc_data *assoc_data)
 {
-	unsigned int rates_len, supp_rates_len;
-	u32 rates = 0;
-	int i, count;
-	u8 *pos;
+	u32 rates;
 
 	if (assoc_data->supp_rates_len) {
 		/*
@@ -1122,53 +1119,23 @@ static void ieee80211_assoc_add_rates(struct sk_buff *skb,
 		 * in the association request (e.g. D-Link DAP 1353 in
 		 * b-only mode)...
 		 */
-		rates_len = ieee80211_parse_bitrates(width, sband,
-						     assoc_data->supp_rates,
-						     assoc_data->supp_rates_len,
-						     &rates);
+		ieee80211_parse_bitrates(width, sband,
+					 assoc_data->supp_rates,
+					 assoc_data->supp_rates_len,
+					 &rates);
 	} else {
 		/*
 		 * In case AP not provide any supported rates information
 		 * before association, we send information element(s) with
 		 * all rates that we support.
 		 */
-		rates_len = sband->n_bitrates;
-		for (i = 0; i < sband->n_bitrates; i++)
-			rates |= BIT(i);
-	}
-
-	supp_rates_len = rates_len;
-	if (supp_rates_len > 8)
-		supp_rates_len = 8;
-
-	pos = skb_put(skb, supp_rates_len + 2);
-	*pos++ = WLAN_EID_SUPP_RATES;
-	*pos++ = supp_rates_len;
-
-	count = 0;
-	for (i = 0; i < sband->n_bitrates; i++) {
-		if (BIT(i) & rates) {
-			int rate = DIV_ROUND_UP(sband->bitrates[i].bitrate, 5);
-			*pos++ = (u8)rate;
-			if (++count == 8)
-				break;
-		}
+		rates = ~0;
 	}
 
-	if (rates_len > count) {
-		pos = skb_put(skb, rates_len - count + 2);
-		*pos++ = WLAN_EID_EXT_SUPP_RATES;
-		*pos++ = rates_len - count;
-
-		for (i++; i < sband->n_bitrates; i++) {
-			if (BIT(i) & rates) {
-				int rate;
-
-				rate = DIV_ROUND_UP(sband->bitrates[i].bitrate, 5);
-				*pos++ = (u8)rate;
-			}
-		}
-	}
+	ieee80211_put_srates_elem(skb, sband, 0, 0, ~rates,
+				  WLAN_EID_SUPP_RATES);
+	ieee80211_put_srates_elem(skb, sband, 0, 0, ~rates,
+				  WLAN_EID_EXT_SUPP_RATES);
 }
 
 static size_t ieee80211_add_before_ht_elems(struct sk_buff *skb,

net/mac80211/tdls.c

@@ -382,8 +382,8 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_link_data *link,
 	if (WARN_ON_ONCE(!sband))
 		return;
 
-	ieee80211_add_srates_ie(sdata, skb, false, sband->band);
-	ieee80211_add_ext_srates_ie(sdata, skb, false, sband->band);
+	ieee80211_put_srates_elem(skb, sband, 0, 0, 0, WLAN_EID_SUPP_RATES);
+	ieee80211_put_srates_elem(skb, sband, 0, 0, 0, WLAN_EID_EXT_SUPP_RATES);
 	ieee80211_tdls_add_supp_channels(sdata, skb);
 
 	/* add any custom IEs that go before Extended Capabilities */

net/mac80211/util.c

@@ -4091,93 +4091,62 @@ int ieee80211_parse_bitrates(enum nl80211_chan_width width,
 	return count;
 }
 
-int ieee80211_add_srates_ie(struct ieee80211_sub_if_data *sdata,
-			    struct sk_buff *skb, bool need_basic,
-			    enum nl80211_band band)
+int ieee80211_put_srates_elem(struct sk_buff *skb,
+			      const struct ieee80211_supported_band *sband,
+			      u32 basic_rates, u32 rate_flags, u32 masked_rates,
+			      u8 element_id)
 {
-	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_supported_band *sband;
-	int rate;
-	u8 i, rates, *pos;
-	u32 basic_rates = sdata->vif.bss_conf.basic_rates;
-	u32 rate_flags;
+	u8 i, rates, skip;
 
-	rate_flags =
-		ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
-	sband = local->hw.wiphy->bands[band];
 	rates = 0;
 	for (i = 0; i < sband->n_bitrates; i++) {
 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 			continue;
+		if (masked_rates & BIT(i))
+			continue;
 		rates++;
 	}
-	if (rates > 8)
-		rates = 8;
 
-	if (skb_tailroom(skb) < rates + 2)
-		return -ENOMEM;
-
-	pos = skb_put(skb, rates + 2);
-	*pos++ = WLAN_EID_SUPP_RATES;
-	*pos++ = rates;
-	for (i = 0; i < rates; i++) {
-		u8 basic = 0;
-		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
-			continue;
-
-		if (need_basic && basic_rates & BIT(i))
-			basic = 0x80;
-		rate = DIV_ROUND_UP(sband->bitrates[i].bitrate, 5);
-		*pos++ = basic | (u8) rate;
+	if (element_id == WLAN_EID_SUPP_RATES) {
+		rates = min_t(u8, rates, 8);
+		skip = 0;
+	} else {
+		skip = 8;
+		if (rates <= skip)
+			return 0;
+		rates -= skip;
 	}
 
-	return 0;
-}
+	if (skb_tailroom(skb) < rates + 2)
+		return -ENOBUFS;
 
-int ieee80211_add_ext_srates_ie(struct ieee80211_sub_if_data *sdata,
-				struct sk_buff *skb, bool need_basic,
-				enum nl80211_band band)
-{
-	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_supported_band *sband;
-	int rate;
-	u8 i, exrates, *pos;
-	u32 basic_rates = sdata->vif.bss_conf.basic_rates;
-	u32 rate_flags;
+	skb_put_u8(skb, element_id);
+	skb_put_u8(skb, rates);
+
+	for (i = 0; i < sband->n_bitrates && rates; i++) {
+		int rate;
+		u8 basic;
 
-	rate_flags =
-		ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
-	sband = local->hw.wiphy->bands[band];
-	exrates = 0;
-	for (i = 0; i < sband->n_bitrates; i++) {
 		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
 			continue;
-		exrates++;
-	}
+		if (masked_rates & BIT(i))
+			continue;
 
-	if (exrates > 8)
-		exrates -= 8;
-	else
-		exrates = 0;
+		if (skip > 0) {
+			skip--;
+			continue;
+		}
 
-	if (skb_tailroom(skb) < exrates + 2)
-		return -ENOMEM;
+		basic = basic_rates & BIT(i) ? 0x80 : 0;
 
-	if (exrates) {
-		pos = skb_put(skb, exrates + 2);
-		*pos++ = WLAN_EID_EXT_SUPP_RATES;
-		*pos++ = exrates;
-		for (i = 8; i < sband->n_bitrates; i++) {
-			u8 basic = 0;
-			if ((rate_flags & sband->bitrates[i].flags)
-			    != rate_flags)
-				continue;
-			if (need_basic && basic_rates & BIT(i))
-				basic = 0x80;
-			rate = DIV_ROUND_UP(sband->bitrates[i].bitrate, 5);
-			*pos++ = basic | (u8) rate;
-		}
+		rate = DIV_ROUND_UP(sband->bitrates[i].bitrate, 5);
+		skb_put_u8(skb, basic | (u8)rate);
+		rates--;
 	}
+
+	WARN(rates > 0, "rates confused: rates:%d, element:%d\n",
+	     rates, element_id);
+
 	return 0;
 }