mac80211: backport support for background radar detection

Will be used in an upcoming mt76 update

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 183 insertions, 0 deletions

diff --git a/package/kernel/mac80211/patches/subsys/315-cfg80211-move-offchan_cac_event-to-a-dedicated-work.patch b/package/kernel/mac80211/patches/subsys/315-cfg80211-move-offchan_cac_event-to-a-dedicated-work.patch
new file mode 100644
index 0000000000..e58c3b99be
--- /dev/null
+++ b/package/kernel/mac80211/patches/subsys/315-cfg80211-move-offchan_cac_event-to-a-dedicated-work.patch
@@ -0,0 +1,183 @@
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Wed, 27 Oct 2021 11:03:42 +0200
+Subject: [PATCH] cfg80211: move offchan_cac_event to a dedicated work
+
+In order to make cfg80211_offchan_cac_abort() (renamed from
+cfg80211_offchan_cac_event) callable in other contexts and
+without so much locking restrictions, make it trigger a new
+work instead of operating directly.
+
+Do some other renames while at it to clarify.
+
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Link: https://lore.kernel.org/r/6145c3d0f30400a568023f67981981d24c7c6133.1635325205.git.lorenzo@kernel.org
+[rewrite commit log]
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+---
+
+--- a/include/net/cfg80211.h
++++ b/include/net/cfg80211.h
+@@ -7620,19 +7620,13 @@ void cfg80211_cac_event(struct net_devic
+ 			enum nl80211_radar_event event, gfp_t gfp);
+ 
+ /**
+- * cfg80211_offchan_cac_event - Channel Availability Check (CAC) offchan event
++ * cfg80211_offchan_cac_abort - Channel Availability Check offchan abort event
+  * @wiphy: the wiphy
+- * @chandef: chandef for the current channel
+- * @event: type of event
+  *
+- * This function is called when a Channel Availability Check (CAC) is finished,
+- * started or aborted by a offchannel dedicated chain.
+- *
+- * Note that this acquires the wiphy lock.
++ * This function is called by the driver when a Channel Availability Check
++ * (CAC) is aborted by a offchannel dedicated chain.
+  */
+-void cfg80211_offchan_cac_event(struct wiphy *wiphy,
+-				const struct cfg80211_chan_def *chandef,
+-				enum nl80211_radar_event event);
++void cfg80211_offchan_cac_abort(struct wiphy *wiphy);
+ 
+ /**
+  * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying
+--- a/net/wireless/core.c
++++ b/net/wireless/core.c
+@@ -552,7 +552,9 @@ use_default_name:
+ 	INIT_WORK(&rdev->rfkill_block, cfg80211_rfkill_block_work);
+ 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
+ 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
+-	INIT_DELAYED_WORK(&rdev->offchan_cac_work, cfg80211_offchan_cac_work);
++	INIT_WORK(&rdev->offchan_cac_abort_wk, cfg80211_offchan_cac_abort_wk);
++	INIT_DELAYED_WORK(&rdev->offchan_cac_done_wk,
++			  cfg80211_offchan_cac_done_wk);
+ 
+ 	init_waitqueue_head(&rdev->dev_wait);
+ 
+@@ -1062,11 +1064,13 @@ void wiphy_unregister(struct wiphy *wiph
+ 	cancel_work_sync(&rdev->conn_work);
+ 	flush_work(&rdev->event_work);
+ 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
++	cancel_delayed_work_sync(&rdev->offchan_cac_done_wk);
+ 	flush_work(&rdev->destroy_work);
+ 	flush_work(&rdev->sched_scan_stop_wk);
+ 	flush_work(&rdev->propagate_radar_detect_wk);
+ 	flush_work(&rdev->propagate_cac_done_wk);
+ 	flush_work(&rdev->mgmt_registrations_update_wk);
++	flush_work(&rdev->offchan_cac_abort_wk);
+ 
+ #ifdef CONFIG_PM
+ 	if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
+--- a/net/wireless/core.h
++++ b/net/wireless/core.h
+@@ -86,7 +86,8 @@ struct cfg80211_registered_device {
+ 
+ 	struct wireless_dev *offchan_radar_wdev;
+ 	struct cfg80211_chan_def offchan_radar_chandef;
+-	struct delayed_work offchan_cac_work;
++	struct delayed_work offchan_cac_done_wk;
++	struct work_struct offchan_cac_abort_wk;
+ 
+ 	/* netlink port which started critical protocol (0 means not started) */
+ 	u32 crit_proto_nlportid;
+@@ -502,7 +503,9 @@ cfg80211_start_offchan_radar_detection(s
+ 
+ void cfg80211_stop_offchan_radar_detection(struct wireless_dev *wdev);
+ 
+-void cfg80211_offchan_cac_work(struct work_struct *work);
++void cfg80211_offchan_cac_done_wk(struct work_struct *work);
++
++void cfg80211_offchan_cac_abort_wk(struct work_struct *work);
+ 
+ bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy,
+ 				  struct ieee80211_channel *chan);
+--- a/net/wireless/mlme.c
++++ b/net/wireless/mlme.c
+@@ -971,17 +971,6 @@ void cfg80211_cac_event(struct net_devic
+ }
+ EXPORT_SYMBOL(cfg80211_cac_event);
+ 
+-void cfg80211_offchan_cac_work(struct work_struct *work)
+-{
+-	struct delayed_work *delayed_work = to_delayed_work(work);
+-	struct cfg80211_registered_device *rdev;
+-
+-	rdev = container_of(delayed_work, struct cfg80211_registered_device,
+-			    offchan_cac_work);
+-	cfg80211_offchan_cac_event(&rdev->wiphy, &rdev->offchan_radar_chandef,
+-				   NL80211_RADAR_CAC_FINISHED);
+-}
+-
+ static void
+ __cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
+ 			     struct wireless_dev *wdev,
+@@ -1006,7 +995,7 @@ __cfg80211_offchan_cac_event(struct cfg8
+ 		rdev->offchan_radar_wdev = NULL;
+ 		break;
+ 	case NL80211_RADAR_CAC_ABORTED:
+-		cancel_delayed_work(&rdev->offchan_cac_work);
++		cancel_delayed_work(&rdev->offchan_cac_done_wk);
+ 		wdev = rdev->offchan_radar_wdev;
+ 		rdev->offchan_radar_wdev = NULL;
+ 		break;
+@@ -1022,17 +1011,44 @@ __cfg80211_offchan_cac_event(struct cfg8
+ 	nl80211_radar_notify(rdev, chandef, event, netdev, GFP_KERNEL);
+ }
+ 
+-void cfg80211_offchan_cac_event(struct wiphy *wiphy,
+-				const struct cfg80211_chan_def *chandef,
+-				enum nl80211_radar_event event)
++static void
++cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev,
++			   const struct cfg80211_chan_def *chandef,
++			   enum nl80211_radar_event event)
++{
++	wiphy_lock(&rdev->wiphy);
++	__cfg80211_offchan_cac_event(rdev, NULL, chandef, event);
++	wiphy_unlock(&rdev->wiphy);
++}
++
++void cfg80211_offchan_cac_done_wk(struct work_struct *work)
++{
++	struct delayed_work *delayed_work = to_delayed_work(work);
++	struct cfg80211_registered_device *rdev;
++
++	rdev = container_of(delayed_work, struct cfg80211_registered_device,
++			    offchan_cac_done_wk);
++	cfg80211_offchan_cac_event(rdev, &rdev->offchan_radar_chandef,
++				   NL80211_RADAR_CAC_FINISHED);
++}
++
++void cfg80211_offchan_cac_abort_wk(struct work_struct *work)
++{
++	struct cfg80211_registered_device *rdev;
++
++	rdev = container_of(work, struct cfg80211_registered_device,
++			    offchan_cac_abort_wk);
++	cfg80211_offchan_cac_event(rdev, &rdev->offchan_radar_chandef,
++				   NL80211_RADAR_CAC_ABORTED);
++}
++
++void cfg80211_offchan_cac_abort(struct wiphy *wiphy)
+ {
+ 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
+ 
+-	wiphy_lock(wiphy);
+-	__cfg80211_offchan_cac_event(rdev, NULL, chandef, event);
+-	wiphy_unlock(wiphy);
++	queue_work(cfg80211_wq, &rdev->offchan_cac_abort_wk);
+ }
+-EXPORT_SYMBOL(cfg80211_offchan_cac_event);
++EXPORT_SYMBOL(cfg80211_offchan_cac_abort);
+ 
+ int
+ cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev,
+@@ -1062,7 +1078,7 @@ cfg80211_start_offchan_radar_detection(s
+ 	rdev->offchan_radar_chandef = *chandef;
+ 	__cfg80211_offchan_cac_event(rdev, wdev, chandef,
+ 				     NL80211_RADAR_CAC_STARTED);
+-	queue_delayed_work(cfg80211_wq, &rdev->offchan_cac_work,
++	queue_delayed_work(cfg80211_wq, &rdev->offchan_cac_done_wk,
+ 			   msecs_to_jiffies(cac_time_ms));
+ 
+ 	return 0;