cfg80211/mac80211: avoid bounce back mac->cfg->mac on sched_scan_stopped

When sched_scan_stopped was called by the driver, mac80211 calls
cfg80211, which in turn was calling mac80211 back with a flag
"driver_initiated".  This flag was used so that mac80211 would do the
necessary cleanup but would not call the driver.  This was enough to
prevent the bounce back between the driver and mac80211, but not
between mac80211 and cfg80211.

To fix this, we now do the cleanup in mac80211 before calling
cfg80211.  To help with locking issues, the workqueue was moved from
cfg80211 to mac80211.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 14 deletions

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 65dfae3b9d41..73a441d237b5 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -119,22 +119,14 @@ void cfg80211_sched_scan_results(struct wiphy *wiphy)
 }
 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 
-void __cfg80211_sched_scan_stopped(struct work_struct *wk)
+void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 {
-        struct cfg80211_registered_device *rdev;
-
-        rdev = container_of(wk, struct cfg80211_registered_device,
-                            sched_scan_stopped_wk);
+        struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 
         cfg80211_lock_rdev(rdev);
         __cfg80211_stop_sched_scan(rdev, true);
         cfg80211_unlock_rdev(rdev);
 }
-
-void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
-{
-        queue_work(cfg80211_wq, &wiphy_to_dev(wiphy)->sched_scan_stopped_wk);
-}
 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 
 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
@@ -150,10 +142,11 @@ int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 
         dev = rdev->sched_scan_req->dev;
 
-        err = rdev->ops->sched_scan_stop(&rdev->wiphy, dev,
-                                         driver_initiated);
-        if (err)
-                return err;
+        if (!driver_initiated) {
+                err = rdev->ops->sched_scan_stop(&rdev->wiphy, dev);
+                if (err)
+                        return err;
+        }
 
         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);