diff mbox series

[v2,07/10] wifi: mac80211: extend ifcomb check functions for multi-radio

Message ID b136fe952d4a202da8831b18f3b17012354372c6.1719733819.git-series.nbd@nbd.name
State Superseded
Headers show
Series cfg80211/mac80211: support defining multiple radios per wiphy | expand

Commit Message

Felix Fietkau June 30, 2024, 7:50 a.m. UTC 
Add support for counting global and per-radio max/current number of
channels, as well as checking radio-specific interface combinations.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 net/mac80211/cfg.c         |   7 +-
 net/mac80211/chan.c        |  17 +++--
 net/mac80211/ibss.c        |   2 +-
 net/mac80211/ieee80211_i.h |   5 +-
 net/mac80211/iface.c       |   2 +-
 net/mac80211/util.c        | 126 ++++++++++++++++++++++++++------------
 6 files changed, 108 insertions(+), 51 deletions(-)

Comments

Johannes Berg July 1, 2024, 1:39 p.m. UTC | #1 
On Sun, 2024-06-30 at 09:50 +0200, Felix Fietkau wrote:
> 
> +++ b/net/mac80211/ieee80211_i.h
> @@ -2043,6 +2043,7 @@ static inline bool ieee80211_sdata_running(struct ieee80211_sub_if_data *sdata)
>  {
>  	return test_bit(SDATA_STATE_RUNNING, &sdata->state);
>  }
> +u32 ieee80211_get_radio_mask(struct wiphy *wiphy, struct net_device *dev);

nit: I feel like maybe there's a better place, and even if not there
should be a blank line? :)

>  
>  /* link handling */
>  void ieee80211_link_setup(struct ieee80211_link_data *link);
> @@ -2640,8 +2641,8 @@ void ieee80211_recalc_dtim(struct ieee80211_local *local,
>  int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
>  				 const struct cfg80211_chan_def *chandef,
>  				 enum ieee80211_chanctx_mode chanmode,
> -				 u8 radar_detect);
> -int ieee80211_max_num_channels(struct ieee80211_local *local);
> +				 u8 radar_detect, int radio_idx);
> +int ieee80211_max_num_channels(struct ieee80211_local *local, int radio_idx);
>  void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
>  				       struct ieee80211_chanctx *ctx);

but maybe just put it next to ieee80211_max_num_channels()?

> +static u32
> +__ieee80211_get_radio_mask(struct ieee80211_sub_if_data *sdata)
> +{
> +	struct ieee80211_bss_conf *link_conf;
> +	struct ieee80211_chanctx_conf *conf;
> +	unsigned int link_id;
> +	u32 mask = 0;
> +
> +	for_each_vif_active_link(&sdata->vif, link_conf, link_id) {
> +		conf = rcu_dereference(link_conf->chanctx_conf);
> +		if (!conf || conf->radio_idx < 0)
> +			continue;
> +
> +		mask |= BIT(conf->radio_idx);
> +	}
> +
> +	return mask;
> +}
> +
> +u32 ieee80211_get_radio_mask(struct wiphy *wiphy, struct net_device *dev)
> +{
> +	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
> +
> +	return __ieee80211_get_radio_mask(sdata);

Here's the context stuff I was talking about - you're using
rcu_dereference() when it almost seems it should be sdata_dereference()
(or so, it's all equivalent now with wiphy dereference)?

I'm not sure how this even gets to be in an RCU critical section, e.g.
when called via

> +static bool
> +ieee80211_sdata_uses_radio(struct ieee80211_sub_if_data *sdata, int radio_idx)
> +{
> +	if (radio_idx < 0)
> +		return true;
> +
> +	return __ieee80211_get_radio_mask(sdata) & BIT(radio_idx);
> +}

...

> +static void
> +ieee80211_fill_ifcomb_params(struct ieee80211_local *local,
> +			     struct iface_combination_params *params,
> +			     const struct cfg80211_chan_def *chandef,
> +			     struct ieee80211_sub_if_data *sdata)
> +{

...

> +	list_for_each_entry_rcu(sdata_iter, &local->interfaces, list) {
> +		struct wireless_dev *wdev_iter;
> +
> +		wdev_iter = &sdata_iter->wdev;
> +
> +		if (sdata_iter == sdata ||
> +		    !ieee80211_sdata_running(sdata_iter) ||
> +		    cfg80211_iftype_allowed(local->hw.wiphy,
> +					    wdev_iter->iftype, 0, 1))
> +			continue;
> +
> +		if (!ieee80211_sdata_uses_radio(sdata_iter, params->radio_idx))
> +			continue;


here?

Also the list_for_each_entry_rcu() seems weird (although I see that we
even have pre-existing code like that now), because e.g.

 ieee80211_open()
-> ieee80211_check_concurrent_iface()
-> ieee80211_check_combinations()

is called outside RCU critical section? There's an existing
list_for_each_entry_rcu() inside of it which seems like it should be a
problem, so maybe I'm missing something?

... investigates a bit ...

yeah I can't get even CONFIG_PROVE_RCU_LIST to spit out warnings, but
checking manually, we (generally) aren't in RCU critical section here,
at least not unconditionally.

johannes
diff mbox series

Patch

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 3d49b3ee3a2b..85cb71de370f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -263,7 +263,7 @@  static int ieee80211_start_p2p_device(struct wiphy *wiphy,
 
 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
 
-	ret = ieee80211_check_combinations(sdata, NULL, 0, 0);
+	ret = ieee80211_check_combinations(sdata, NULL, 0, 0, -1);
 	if (ret < 0)
 		return ret;
 
@@ -285,7 +285,7 @@  static int ieee80211_start_nan(struct wiphy *wiphy,
 
 	lockdep_assert_wiphy(sdata->local->hw.wiphy);
 
-	ret = ieee80211_check_combinations(sdata, NULL, 0, 0);
+	ret = ieee80211_check_combinations(sdata, NULL, 0, 0, -1);
 	if (ret < 0)
 		return ret;
 
@@ -4008,7 +4008,7 @@  __ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
 		goto out;
 
 	/* if reservation is invalid then this will fail */
-	err = ieee80211_check_combinations(sdata, NULL, chanctx->mode, 0);
+	err = ieee80211_check_combinations(sdata, NULL, chanctx->mode, 0, -1);
 	if (err) {
 		ieee80211_link_unreserve_chanctx(link_data);
 		goto out;
@@ -5203,4 +5203,5 @@  const struct cfg80211_ops mac80211_config_ops = {
 	.del_link_station = ieee80211_del_link_station,
 	.set_hw_timestamp = ieee80211_set_hw_timestamp,
 	.set_ttlm = ieee80211_set_ttlm,
+	.get_radio_mask = ieee80211_get_radio_mask,
 };
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 6c4d02cb07bb..12bad02da561 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -47,24 +47,29 @@  int ieee80211_chanctx_refcount(struct ieee80211_local *local,
 	       ieee80211_chanctx_num_reserved(local, ctx);
 }
 
-static int ieee80211_num_chanctx(struct ieee80211_local *local)
+static int ieee80211_num_chanctx(struct ieee80211_local *local, int radio_idx)
 {
 	struct ieee80211_chanctx *ctx;
 	int num = 0;
 
 	lockdep_assert_wiphy(local->hw.wiphy);
 
-	list_for_each_entry(ctx, &local->chanctx_list, list)
+	list_for_each_entry(ctx, &local->chanctx_list, list) {
+		if (radio_idx >= 0 && ctx->conf.radio_idx != radio_idx)
+			continue;
 		num++;
+	}
 
 	return num;
 }
 
-static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local)
+static bool ieee80211_can_create_new_chanctx(struct ieee80211_local *local,
+					     int radio_idx)
 {
 	lockdep_assert_wiphy(local->hw.wiphy);
 
-	return ieee80211_num_chanctx(local) < ieee80211_max_num_channels(local);
+	return ieee80211_num_chanctx(local, radio_idx) <
+	       ieee80211_max_num_channels(local, radio_idx);
 }
 
 static struct ieee80211_chanctx *
@@ -1101,7 +1106,7 @@  int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
 
 	new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
 	if (!new_ctx) {
-		if (ieee80211_can_create_new_chanctx(local)) {
+		if (ieee80211_can_create_new_chanctx(local, -1)) {
 			new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
 							false);
 			if (IS_ERR(new_ctx))
@@ -1822,7 +1827,7 @@  int _ieee80211_link_use_channel(struct ieee80211_link_data *link,
 	link->radar_required = ret;
 
 	ret = ieee80211_check_combinations(sdata, &chanreq->oper, mode,
-					   radar_detect_width);
+					   radar_detect_width, -1);
 	if (ret < 0)
 		goto out;
 
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 7db4c3ee7e6d..3f74bbceeca5 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -1746,7 +1746,7 @@  int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
 		IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE;
 
 	ret = ieee80211_check_combinations(sdata, &params->chandef, chanmode,
-					   radar_detect_width);
+					   radar_detect_width, -1);
 	if (ret < 0)
 		return ret;
 
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 6349552e62a8..9d941436bade 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -2043,6 +2043,7 @@  static inline bool ieee80211_sdata_running(struct ieee80211_sub_if_data *sdata)
 {
 	return test_bit(SDATA_STATE_RUNNING, &sdata->state);
 }
+u32 ieee80211_get_radio_mask(struct wiphy *wiphy, struct net_device *dev);
 
 /* link handling */
 void ieee80211_link_setup(struct ieee80211_link_data *link);
@@ -2640,8 +2641,8 @@  void ieee80211_recalc_dtim(struct ieee80211_local *local,
 int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
 				 const struct cfg80211_chan_def *chandef,
 				 enum ieee80211_chanctx_mode chanmode,
-				 u8 radar_detect);
-int ieee80211_max_num_channels(struct ieee80211_local *local);
+				 u8 radar_detect, int radio_idx);
+int ieee80211_max_num_channels(struct ieee80211_local *local, int radio_idx);
 void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
 				       struct ieee80211_chanctx *ctx);
 
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 6d969d9f1ac9..adf907e15d70 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -397,7 +397,7 @@  static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
 		}
 	}
 
-	return ieee80211_check_combinations(sdata, NULL, 0, 0);
+	return ieee80211_check_combinations(sdata, NULL, 0, 0, -1);
 }
 
 static int ieee80211_check_queues(struct ieee80211_sub_if_data *sdata,
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 27f0db2e9796..010adb614c6a 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -3932,19 +3932,99 @@  static u8 ieee80211_chanctx_radar_detect(struct ieee80211_local *local,
 	return radar_detect;
 }
 
+static u32
+__ieee80211_get_radio_mask(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_bss_conf *link_conf;
+	struct ieee80211_chanctx_conf *conf;
+	unsigned int link_id;
+	u32 mask = 0;
+
+	for_each_vif_active_link(&sdata->vif, link_conf, link_id) {
+		conf = rcu_dereference(link_conf->chanctx_conf);
+		if (!conf || conf->radio_idx < 0)
+			continue;
+
+		mask |= BIT(conf->radio_idx);
+	}
+
+	return mask;
+}
+
+u32 ieee80211_get_radio_mask(struct wiphy *wiphy, struct net_device *dev)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+	return __ieee80211_get_radio_mask(sdata);
+}
+
+static bool
+ieee80211_sdata_uses_radio(struct ieee80211_sub_if_data *sdata, int radio_idx)
+{
+	if (radio_idx < 0)
+		return true;
+
+	return __ieee80211_get_radio_mask(sdata) & BIT(radio_idx);
+}
+
+static void
+ieee80211_fill_ifcomb_params(struct ieee80211_local *local,
+			     struct iface_combination_params *params,
+			     const struct cfg80211_chan_def *chandef,
+			     struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_sub_if_data *sdata_iter;
+	struct ieee80211_chanctx *ctx;
+
+	list_for_each_entry(ctx, &local->chanctx_list, list) {
+		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
+			continue;
+
+		if (params->radio_idx >= 0 &&
+		    ctx->conf.radio_idx != params->radio_idx)
+			continue;
+
+		if (chandef &&
+		    cfg80211_chandef_compatible(chandef, &ctx->conf.def))
+			continue;
+
+		params->num_different_channels++;
+
+		params->radar_detect |=
+			ieee80211_chanctx_radar_detect(local, ctx);
+	}
+
+	list_for_each_entry_rcu(sdata_iter, &local->interfaces, list) {
+		struct wireless_dev *wdev_iter;
+
+		wdev_iter = &sdata_iter->wdev;
+
+		if (sdata_iter == sdata ||
+		    !ieee80211_sdata_running(sdata_iter) ||
+		    cfg80211_iftype_allowed(local->hw.wiphy,
+					    wdev_iter->iftype, 0, 1))
+			continue;
+
+		if (!ieee80211_sdata_uses_radio(sdata_iter, params->radio_idx))
+			continue;
+
+		params->iftype_num[wdev_iter->iftype]++;
+	}
+}
+
 int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
 				 const struct cfg80211_chan_def *chandef,
 				 enum ieee80211_chanctx_mode chanmode,
-				 u8 radar_detect)
+				 u8 radar_detect, int radio_idx)
 {
+	bool shared = chanmode == IEEE80211_CHANCTX_SHARED;
 	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_sub_if_data *sdata_iter;
 	enum nl80211_iftype iftype = sdata->wdev.iftype;
 	struct ieee80211_chanctx *ctx;
 	int total = 1;
 	struct iface_combination_params params = {
 		.radar_detect = radar_detect,
-		.radio_idx = -1,
+		.radio_idx = radio_idx,
 	};
 
 	lockdep_assert_wiphy(local->hw.wiphy);
@@ -3982,6 +4062,8 @@  int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
 	if (iftype != NL80211_IFTYPE_UNSPECIFIED)
 		params.iftype_num[iftype] = 1;
 
+	ieee80211_fill_ifcomb_params(local, &params, shared ? chandef : NULL,
+				     sdata);
 	list_for_each_entry(ctx, &local->chanctx_list, list) {
 		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
 			continue;
@@ -3991,28 +4073,9 @@  int ieee80211_check_combinations(struct ieee80211_sub_if_data *sdata,
 			params.num_different_channels++;
 			continue;
 		}
-		if (chandef && chanmode == IEEE80211_CHANCTX_SHARED &&
-		    cfg80211_chandef_compatible(chandef,
-						&ctx->conf.def))
-			continue;
 		params.num_different_channels++;
 	}
 
-	list_for_each_entry_rcu(sdata_iter, &local->interfaces, list) {
-		struct wireless_dev *wdev_iter;
-
-		wdev_iter = &sdata_iter->wdev;
-
-		if (sdata_iter == sdata ||
-		    !ieee80211_sdata_running(sdata_iter) ||
-		    cfg80211_iftype_allowed(local->hw.wiphy,
-					    wdev_iter->iftype, 0, 1))
-			continue;
-
-		params.iftype_num[wdev_iter->iftype]++;
-		total++;
-	}
-
 	if (total == 1 && !params.radar_detect)
 		return 0;
 
@@ -4029,30 +4092,17 @@  ieee80211_iter_max_chans(const struct ieee80211_iface_combination *c,
 					  c->num_different_channels);
 }
 
-int ieee80211_max_num_channels(struct ieee80211_local *local)
+int ieee80211_max_num_channels(struct ieee80211_local *local, int radio_idx)
 {
-	struct ieee80211_sub_if_data *sdata;
-	struct ieee80211_chanctx *ctx;
 	u32 max_num_different_channels = 1;
 	int err;
 	struct iface_combination_params params = {
-		.radio_idx = -1,
+		.radio_idx = radio_idx,
 	};
 
 	lockdep_assert_wiphy(local->hw.wiphy);
 
-	list_for_each_entry(ctx, &local->chanctx_list, list) {
-		if (ctx->replace_state == IEEE80211_CHANCTX_WILL_BE_REPLACED)
-			continue;
-
-		params.num_different_channels++;
-
-		params.radar_detect |=
-			ieee80211_chanctx_radar_detect(local, ctx);
-	}
-
-	list_for_each_entry_rcu(sdata, &local->interfaces, list)
-		params.iftype_num[sdata->wdev.iftype]++;
+	ieee80211_fill_ifcomb_params(local, &params, NULL, NULL);
 
 	err = cfg80211_iter_combinations(local->hw.wiphy, &params,
 					 ieee80211_iter_max_chans,