Re: [PATCH 01/15] wifi: mac80211: add support for mld in ieee80211_chswitch_done

[Jeff Johnson <quic_jjohnson@quicinc.com>]

On 8/27/2023 4:05 AM, gregory.greenman@intel.com wrote:
> From: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
> 
> This allows to finalize the CSA per link.
> In case the switch didn't work, tear down the MLD connection.
> Also pass the ieee80211_bss_conf to post_channel_switch to let the
> driver know which link completed the switch.
> 
> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
> Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
> ---
>   .../net/wireless/intel/iwlegacy/4965-mac.c    |  2 +-
>   drivers/net/wireless/intel/iwlegacy/common.c  |  2 +-
>   .../net/wireless/intel/iwlwifi/dvm/mac80211.c |  6 ++--
>   .../net/wireless/intel/iwlwifi/mvm/mac-ctxt.c |  2 +-
>   .../net/wireless/intel/iwlwifi/mvm/mac80211.c | 10 +++---
>   drivers/net/wireless/intel/iwlwifi/mvm/mvm.h  |  3 +-
>   .../wireless/intel/iwlwifi/mvm/time-event.c   |  2 +-
>   drivers/net/wireless/ti/wlcore/event.c        |  2 +-
>   drivers/net/wireless/ti/wlcore/main.c         |  6 ++--
>   include/net/mac80211.h                        |  8 +++--
>   net/mac80211/cfg.c                            | 35 ++++++++++---------
>   net/mac80211/driver-ops.h                     |  6 ++--
>   net/mac80211/mlme.c                           | 29 ++++++++++-----
...
> diff --git a/include/net/mac80211.h b/include/net/mac80211.h
> index 7c707358d15c..67f54825110f 100644
> --- a/include/net/mac80211.h
> +++ b/include/net/mac80211.h
> @@ -4544,7 +4544,8 @@ struct ieee80211_ops {
>   				  struct ieee80211_channel_switch *ch_switch);
>   
>   	int (*post_channel_switch)(struct ieee80211_hw *hw,
> -				   struct ieee80211_vif *vif);
> +				   struct ieee80211_vif *vif,
> +				   struct ieee80211_bss_conf *link_conf);
>   	void (*abort_channel_switch)(struct ieee80211_hw *hw,
>   				     struct ieee80211_vif *vif);
>   	void (*channel_switch_rx_beacon)(struct ieee80211_hw *hw,
> @@ -6542,11 +6543,14 @@ void ieee80211_radar_detected(struct ieee80211_hw *hw);
>    * ieee80211_chswitch_done - Complete channel switch process
>    * @vif: &struct ieee80211_vif pointer from the add_interface callback.
>    * @success: make the channel switch successful or not
> + * @link_id: the link_id on which the switch was done. Ignored if success is
> + *	false.

I would not call this being ignored:
+	link = rcu_dereference(sdata->link[link_id]);
+	if (WARN_ON(!link)) {
+		rcu_read_unlock();
+		return;
+	}

>    *
>    * Complete the channel switch post-process: set the new operational channel
>    * and wake up the suspended queues.
>    */
> -void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success);
> +void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success,
> +			     unsigned int link_id);
>   
>   /**
>    * ieee80211_channel_switch_disconnect - disconnect due to channel switch error
...
> diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
> index f93eb38ae0b8..ca6045f56b4b 100644
> --- a/net/mac80211/mlme.c
> +++ b/net/mac80211/mlme.c
> @@ -1773,7 +1773,7 @@ static void ieee80211_chswitch_post_beacon(struct ieee80211_link_data *link)
>   	 */
>   	link->u.mgd.beacon_crc_valid = false;
>   
> -	ret = drv_post_channel_switch(sdata);
> +	ret = drv_post_channel_switch(link);
>   	if (ret) {
>   		sdata_info(sdata,
>   			   "driver post channel switch failed, disconnecting\n");
> @@ -1785,25 +1785,36 @@ static void ieee80211_chswitch_post_beacon(struct ieee80211_link_data *link)
>   	cfg80211_ch_switch_notify(sdata->dev, &link->reserved_chandef, 0, 0);
>   }
>   
> -void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success)
> +void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success,
> +			     unsigned int link_id)
>   {
> +	struct ieee80211_link_data *link;
>   	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
> -	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
> -
> -	if (WARN_ON(ieee80211_vif_is_mld(&sdata->vif)))
> -		success = false;
> +	struct ieee80211_link_data_managed *ifmgd;
>   
>   	trace_api_chswitch_done(sdata, success);

no value in tracing the link_id?

> +
> +	rcu_read_lock();
> +
> +	link = rcu_dereference(sdata->link[link_id]);
> +	if (WARN_ON(!link)) {
> +		rcu_read_unlock();
> +		return;
> +	}
> +
> +	ifmgd = &link->u.mgd;
> +
>   	if (!success) {
>   		sdata_info(sdata,
>   			   "driver channel switch failed, disconnecting\n");
>   		wiphy_work_queue(sdata->local->hw.wiphy,
> -				 &ifmgd->csa_connection_drop_work);
> +				 &sdata->u.mgd.csa_connection_drop_work);
>   	} else {
>   		wiphy_delayed_work_queue(sdata->local->hw.wiphy,
> -					 &sdata->deflink.u.mgd.chswitch_work,
> -					 0);
> +					 &ifmgd->chswitch_work, 0);
>   	}
> +
> +	rcu_read_unlock();
>   }
>   EXPORT_SYMBOL(ieee80211_chswitch_done);
>