Commit db2424c5 authored by Johannes Berg's avatar Johannes Berg
Browse files

regulatory: use RCU in regulatory_hint_11d() 



Since it just does a quick check of the last regulatory
request, the function doesn't have to hold the reg mutex
but can use RCU instead.

Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 1cdd59ce

net/wireless/reg.c

+16 −14
Original line number Diff line number Diff line
@@ -1715,20 +1715,18 @@ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, 
{

	char alpha2[2];

	enum environment_cap env = ENVIRON_ANY;

	struct regulatory_request *request, *lr;



	mutex_lock(&reg_mutex);

	lr = get_last_request();



	if (unlikely(!lr))

		goto out;

	struct regulatory_request *request = NULL, *lr;



	/* IE len must be evenly divisible by 2 */

	if (country_ie_len & 0x01)

		goto out;

		return;



	if (country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)

		goto out;

		return;



	request = kzalloc(sizeof(*request), GFP_KERNEL);

	if (!request)

		return;



	alpha2[0] = country_ie[0];

	alpha2[1] = country_ie[1];
@@ -1738,6 +1736,12 @@ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, 
	else if (country_ie[2] == 'O')

		env = ENVIRON_OUTDOOR;



	rcu_read_lock();

	lr = get_last_request();



	if (unlikely(!lr))

		goto out;



	/*

	 * We will run this only upon a successful connection on cfg80211.

	 * We leave conflict resolution to the workqueue, where can hold
@@ -1747,10 +1751,6 @@ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, 
	    lr->wiphy_idx != WIPHY_IDX_INVALID)

		goto out;



	request = kzalloc(sizeof(struct regulatory_request), GFP_KERNEL);

	if (!request)

		goto out;



	request->wiphy_idx = get_wiphy_idx(wiphy);

	request->alpha2[0] = alpha2[0];

	request->alpha2[1] = alpha2[1];
@@ -1758,8 +1758,10 @@ void regulatory_hint_11d(struct wiphy *wiphy, enum ieee80211_band band, 
	request->country_ie_env = env;



	queue_regulatory_request(request);

	request = NULL;

out:

	mutex_unlock(&reg_mutex);

	kfree(request);

	rcu_read_unlock();

}



static void restore_alpha2(char *alpha2, bool reset_user)