mac80211: merge pending cfg80211 patches to fix a race condition with setting the regdomain for multiple cards

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@24028 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/mac80211/patches/310-pending_work.patch

@@ -112,3 +112,181 @@
  	return true;
  }
  
+--- a/include/net/regulatory.h
++++ b/include/net/regulatory.h
+@@ -43,6 +43,12 @@ enum environment_cap {
+  * @intersect: indicates whether the wireless core should intersect
+  * 	the requested regulatory domain with the presently set regulatory
+  * 	domain.
++ * @processed: indicates whether or not this requests has already been
++ *	processed. When the last request is processed it means that the
++ *	currently regulatory domain set on cfg80211 is updated from
++ *	CRDA and can be used by other regulatory requests. When a
++ *	the last request is not yet processed we must yield until it
++ *	is processed before processing any new requests.
+  * @country_ie_checksum: checksum of the last processed and accepted
+  * 	country IE
+  * @country_ie_env: lets us know if the AP is telling us we are outdoor,
+@@ -54,6 +60,7 @@ struct regulatory_request {
+ 	enum nl80211_reg_initiator initiator;
+ 	char alpha2[2];
+ 	bool intersect;
++	bool processed;
+ 	enum environment_cap country_ie_env;
+ 	struct list_head list;
+ };
+--- a/net/wireless/reg.c
++++ b/net/wireless/reg.c
+@@ -96,6 +96,9 @@ struct reg_beacon {
+ 	struct ieee80211_channel chan;
+ };
+ 
++static void reg_todo(struct work_struct *work);
++static DECLARE_WORK(reg_work, reg_todo);
++
+ /* We keep a static world regulatory domain in case of the absence of CRDA */
+ static const struct ieee80211_regdomain world_regdom = {
+ 	.n_reg_rules = 5,
+@@ -1317,6 +1320,21 @@ static int ignore_request(struct wiphy *
+ 	return -EINVAL;
+ }
+ 
++static void reg_set_request_processed(void)
++{
++	bool need_more_processing = false;
++
++	last_request->processed = true;
++
++	spin_lock(&reg_requests_lock);
++	if (!list_empty(&reg_requests_list))
++		need_more_processing = true;
++	spin_unlock(&reg_requests_lock);
++
++	if (need_more_processing)
++		schedule_work(&reg_work);
++}
++
+ /**
+  * __regulatory_hint - hint to the wireless core a regulatory domain
+  * @wiphy: if the hint comes from country information from an AP, this
+@@ -1392,8 +1410,10 @@ new_request:
+ 		 * have applied the requested regulatory domain before we just
+ 		 * inform userspace we have processed the request
+ 		 */
+-		if (r == -EALREADY)
++		if (r == -EALREADY) {
+ 			nl80211_send_reg_change_event(last_request);
++			reg_set_request_processed();
++		}
+ 		return r;
+ 	}
+ 
+@@ -1409,16 +1429,13 @@ static void reg_process_hint(struct regu
+ 
+ 	BUG_ON(!reg_request->alpha2);
+ 
+-	mutex_lock(&cfg80211_mutex);
+-	mutex_lock(&reg_mutex);
+-
+ 	if (wiphy_idx_valid(reg_request->wiphy_idx))
+ 		wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
+ 
+ 	if (reg_request->initiator == NL80211_REGDOM_SET_BY_DRIVER &&
+ 	    !wiphy) {
+ 		kfree(reg_request);
+-		goto out;
++		return;
+ 	}
+ 
+ 	r = __regulatory_hint(wiphy, reg_request);
+@@ -1426,28 +1443,46 @@ static void reg_process_hint(struct regu
+ 	if (r == -EALREADY && wiphy &&
+ 	    wiphy->flags & WIPHY_FLAG_STRICT_REGULATORY)
+ 		wiphy_update_regulatory(wiphy, initiator);
+-out:
+-	mutex_unlock(&reg_mutex);
+-	mutex_unlock(&cfg80211_mutex);
+ }
+ 
+-/* Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_* */
++/*
++ * Processes regulatory hints, this is all the NL80211_REGDOM_SET_BY_*
++ * Regulatory hints come on a first come first serve basis and we
++ * must process each one atomically.
++ */
+ static void reg_process_pending_hints(void)
+-	{
++{
+ 	struct regulatory_request *reg_request;
+ 
++	mutex_lock(&cfg80211_mutex);
++	mutex_lock(&reg_mutex);
++
++	/* When last_request->processed becomes true this will be rescheduled */
++	if (last_request && !last_request->processed) {
++		REG_DBG_PRINT("Pending regulatory request, waiting "
++			      "for it to be processed...");
++		goto out;
++	}
++
+ 	spin_lock(&reg_requests_lock);
+-	while (!list_empty(&reg_requests_list)) {
+-		reg_request = list_first_entry(&reg_requests_list,
+-					       struct regulatory_request,
+-					       list);
+-		list_del_init(&reg_request->list);
+ 
++	if (list_empty(&reg_requests_list)) {
+ 		spin_unlock(&reg_requests_lock);
+-		reg_process_hint(reg_request);
+-		spin_lock(&reg_requests_lock);
++		goto out;
+ 	}
++
++	reg_request = list_first_entry(&reg_requests_list,
++				       struct regulatory_request,
++				       list);
++	list_del_init(&reg_request->list);
++
+ 	spin_unlock(&reg_requests_lock);
++
++	reg_process_hint(reg_request);
++
++out:
++	mutex_unlock(&reg_mutex);
++	mutex_unlock(&cfg80211_mutex);
+ }
+ 
+ /* Processes beacon hints -- this has nothing to do with country IEs */
+@@ -1494,8 +1529,6 @@ static void reg_todo(struct work_struct 
+ 	reg_process_pending_beacon_hints();
+ }
+ 
+-static DECLARE_WORK(reg_work, reg_todo);
+-
+ static void queue_regulatory_request(struct regulatory_request *request)
+ {
+ 	if (isalpha(request->alpha2[0]))
+@@ -1530,12 +1563,7 @@ static int regulatory_hint_core(const ch
+ 	request->alpha2[1] = alpha2[1];
+ 	request->initiator = NL80211_REGDOM_SET_BY_CORE;
+ 
+-	/*
+-	 * This ensures last_request is populated once modules
+-	 * come swinging in and calling regulatory hints and
+-	 * wiphy_apply_custom_regulatory().
+-	 */
+-	reg_process_hint(request);
++	queue_regulatory_request(request);
+ 
+ 	return 0;
+ }
+@@ -2061,6 +2089,8 @@ int set_regdom(const struct ieee80211_re
+ 
+ 	nl80211_send_reg_change_event(last_request);
+ 
++	reg_set_request_processed();
++
+ 	mutex_unlock(&reg_mutex);
+ 
+ 	return r;