mac80211: support runtime interface type changes

Add support to mac80211 for changing the interface
type even when the interface is UP, if the driver
supports it.

To achieve this
 * add a new driver callback for switching,
 * split some of the interface up/down code out
   into new functions (do_open/do_stop), and
 * maintain an own __SDATA_RUNNING bit that will
   not be set during interface type, so that any
   other code doesn't use the interface.

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

1 files changed, 14 insertions, 0 deletions

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index 14123dce544b..6064b7b09e01 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -54,6 +54,20 @@ static inline int drv_add_interface(struct ieee80211_local *local,
         return ret;
 }
 
+static inline int drv_change_interface(struct ieee80211_local *local,
+                                       struct ieee80211_sub_if_data *sdata,
+                                       enum nl80211_iftype type)
+{
+        int ret;
+
+        might_sleep();
+
+        trace_drv_change_interface(local, sdata, type);
+        ret = local->ops->change_interface(&local->hw, &sdata->vif, type);
+        trace_drv_return_int(local, ret);
+        return ret;
+}
+
 static inline void drv_remove_interface(struct ieee80211_local *local,
                                         struct ieee80211_vif *vif)
 {