mac80211: redefine usage of the mac80211 workqueue

The mac80211 workqueue exists to enable mac80211 and drivers
to queue their own work on a single threaded workqueue. mac80211
takes care to flush the workqueue during suspend but we never
really had requirements on drivers for how they should use
the workqueue in consideration for suspend.

We extend mac80211 to document how the mac80211 workqueue should
be used, how it should not be used and finally move raw access to
the workqueue to mac80211 only. Drivers and mac80211 use helpers
to queue work onto the mac80211 workqueue:

  * ieee80211_queue_work()
  * ieee80211_queue_delayed_work()

These helpers will now warn if mac80211 already completed its
suspend cycle and someone is trying to queue work. mac80211
flushes the mac80211 workqueue prior to suspend a few times,
but we haven't taken the care to ensure drivers won't add more
work after suspend. To help with this we add a warning when
someone tries to add work and mac80211 already completed the
suspend cycle.

Drivers should ensure they cancel any work or delayed work
in the mac80211 stop() callback.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/net/wireless/b43legacy/main.c b/drivers/net/wireless/b43legacy/main.c
index c4973c1942b..b1435594921 100644
--- a/drivers/net/wireless/b43legacy/main.c
+++ b/drivers/net/wireless/b43legacy/main.c
@@ -1252,7 +1252,7 @@ static void b43legacy_update_templates(struct b43legacy_wl *wl)
         wl->current_beacon = beacon;
         wl->beacon0_uploaded = 0;
         wl->beacon1_uploaded = 0;
-        queue_work(wl->hw->workqueue, &wl->beacon_update_trigger);
+        ieee80211_queue_work(wl->hw, &wl->beacon_update_trigger);
 }
 
 static void b43legacy_set_beacon_int(struct b43legacy_wldev *dev,
@@ -2300,7 +2300,7 @@ out_requeue:
                 delay = msecs_to_jiffies(50);
         else
                 delay = round_jiffies_relative(HZ * 15);
-        queue_delayed_work(wl->hw->workqueue, &dev->periodic_work, delay);
+        ieee80211_queue_delayed_work(wl->hw, &dev->periodic_work, delay);
 out:
         mutex_unlock(&wl->mutex);
 }
@@ -2311,7 +2311,7 @@ static void b43legacy_periodic_tasks_setup(struct b43legacy_wldev *dev)
 
         dev->periodic_state = 0;
         INIT_DELAYED_WORK(work, b43legacy_periodic_work_handler);
-        queue_delayed_work(dev->wl->hw->workqueue, work, 0);
+        ieee80211_queue_delayed_work(dev->wl->hw, work, 0);
 }
 
 /* Validate access to the chip (SHM) */
@@ -3885,7 +3885,7 @@ void b43legacy_controller_restart(struct b43legacy_wldev *dev,
         if (b43legacy_status(dev) < B43legacy_STAT_INITIALIZED)
                 return;
         b43legacyinfo(dev->wl, "Controller RESET (%s) ...\n", reason);
-        queue_work(dev->wl->hw->workqueue, &dev->restart_work);
+        ieee80211_queue_work(dev->wl->hw, &dev->restart_work);
 }
 
 #ifdef CONFIG_PM