mac80211: allow configure_filter callback to sleep

Over time, a whole bunch of drivers have come up
with their own scheme to delay the configure_filter
operation to a workqueue. To be able to simplify
things, allow configure_filter to sleep, and add
a new prepare_multicast callback that drivers that
need the multicast address list implement. This new
callback must be atomic, but most drivers either
don't care or just calculate a hash which can be
done atomically and then uploaded to the hardware
non-atomically.

A cursory look suggests that at76c50x-usb, ar9170,
mwl8k (which is actually very broken now), rt2x00,
wl1251, wl1271 and zd1211 should make use of this
new capability.

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

1 files changed, 19 insertions, 5 deletions

diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index b03fd84777f..05f923575fe 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -50,9 +50,9 @@ struct ieee80211_tx_status_rtap_hdr {
 } __attribute__ ((packed));
 
 
-/* must be called under mdev tx lock */
 void ieee80211_configure_filter(struct ieee80211_local *local)
 {
+        u64 mc;
         unsigned int changed_flags;
         unsigned int new_flags = 0;
 
@@ -62,7 +62,7 @@ void ieee80211_configure_filter(struct ieee80211_local *local)
         if (atomic_read(&local->iff_allmultis))
                 new_flags |= FIF_ALLMULTI;
 
-        if (local->monitors)
+        if (local->monitors || local->scanning)
                 new_flags |= FIF_BCN_PRBRESP_PROMISC;
 
         if (local->fif_fcsfail)
@@ -80,20 +80,30 @@ void ieee80211_configure_filter(struct ieee80211_local *local)
         if (local->fif_pspoll)
                 new_flags |= FIF_PSPOLL;
 
+        spin_lock_bh(&local->filter_lock);
         changed_flags = local->filter_flags ^ new_flags;
 
+        mc = drv_prepare_multicast(local, local->mc_count, local->mc_list);
+        spin_unlock_bh(&local->filter_lock);
+
         /* be a bit nasty */
         new_flags |= (1<<31);
 
-        drv_configure_filter(local, changed_flags, &new_flags,
-                             local->mc_count,
-                             local->mc_list);
+        drv_configure_filter(local, changed_flags, &new_flags, mc);
 
         WARN_ON(new_flags & (1<<31));
 
         local->filter_flags = new_flags & ~(1<<31);
 }
 
+static void ieee80211_reconfig_filter(struct work_struct *work)
+{
+        struct ieee80211_local *local =
+                container_of(work, struct ieee80211_local, reconfig_filter);
+
+        ieee80211_configure_filter(local);
+}
+
 int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
 {
         struct ieee80211_channel *chan, *scan_chan;
@@ -692,6 +702,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 
         INIT_WORK(&local->restart_work, ieee80211_restart_work);
 
+        INIT_WORK(&local->reconfig_filter, ieee80211_reconfig_filter);
+
         INIT_WORK(&local->dynamic_ps_enable_work,
                   ieee80211_dynamic_ps_enable_work);
         INIT_WORK(&local->dynamic_ps_disable_work,
@@ -946,6 +958,8 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw)
 
         rtnl_unlock();
 
+        cancel_work_sync(&local->reconfig_filter);
+
         ieee80211_clear_tx_pending(local);
         sta_info_stop(local);
         rate_control_deinitialize(local);