cfg80211: add feature to hold bss

In beacon filtering there needs to be a way to not expire the BSS even
when no beacons are received. Add an interface to cfg80211 to hold
BSS and make sure that it's not expired.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 28 insertions, 1 deletions

diff --git a/net/wireless/core.h b/net/wireless/core.h
index 6acd483a61f8..97a6fd8b2b03 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -90,6 +90,8 @@ struct cfg80211_internal_bss {
 	struct rb_node rbn;
 	unsigned long ts;
 	struct kref ref;
+	bool hold;
+
 	/* must be last because of priv member */
 	struct cfg80211_bss pub;
 };
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 280dbcd02c15..2a00e362f5fe 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -80,7 +80,8 @@ void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 	bool expired = false;
 
 	list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
-		if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
+		if (bss->hold ||
+		    !time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
 			continue;
 		list_del(&bss->list);
 		rb_erase(&bss->rbn, &dev->bss_tree);
@@ -471,6 +472,30 @@ void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 }
 EXPORT_SYMBOL(cfg80211_unlink_bss);
 
+void cfg80211_hold_bss(struct cfg80211_bss *pub)
+{
+	struct cfg80211_internal_bss *bss;
+
+	if (!pub)
+		return;
+
+	bss = container_of(pub, struct cfg80211_internal_bss, pub);
+	bss->hold = true;
+}
+EXPORT_SYMBOL(cfg80211_hold_bss);
+
+void cfg80211_unhold_bss(struct cfg80211_bss *pub)
+{
+	struct cfg80211_internal_bss *bss;
+
+	if (!pub)
+		return;
+
+	bss = container_of(pub, struct cfg80211_internal_bss, pub);
+	bss->hold = false;
+}
+EXPORT_SYMBOL(cfg80211_unhold_bss);
+
 #ifdef CONFIG_WIRELESS_EXT
 int cfg80211_wext_siwscan(struct net_device *dev,
 			  struct iw_request_info *info,