mac80211: push interface checks down

This patch pushes the "netif_running()" and "same type as before"
checks down into ieee80211_if_change_type() to centralise the
logic instead of duplicating it for cfg80211 and wext.

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

4 files changed, 25 insertions, 16 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 6aa49ad172aa..ea0301025c15 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -84,22 +84,22 @@ static int ieee80211_change_iface(struct wiphy *wiphy, int ifindex,
         struct net_device *dev;
         enum ieee80211_if_types itype;
         struct ieee80211_sub_if_data *sdata;
+        int ret;
 
         /* we're under RTNL */
         dev = __dev_get_by_index(&init_net, ifindex);
         if (!dev)
                 return -ENODEV;
 
-        if (netif_running(dev))
-                return -EBUSY;
-
         itype = nl80211_type_to_mac80211_type(type);
         if (itype == IEEE80211_IF_TYPE_INVALID)
                 return -EINVAL;
 
         sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
-        ieee80211_if_change_type(sdata, itype);
+        ret = ieee80211_if_change_type(sdata, itype);
+        if (ret)
+                return ret;
 
         if (ieee80211_vif_is_mesh(&sdata->vif) && params->mesh_id_len)
                 ieee80211_if_sta_set_mesh_id(&sdata->u.sta,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 35bcdfef9045..2146c0c436d2 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -930,8 +930,8 @@ void ieee80211_if_setup(struct net_device *dev);
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
                      struct net_device **new_dev, enum ieee80211_if_types type,
                      struct vif_params *params);
-void ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
-                              enum ieee80211_if_types type);
+int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
+                             enum ieee80211_if_types type);
 void ieee80211_if_remove(struct net_device *dev);
 void ieee80211_remove_interfaces(struct ieee80211_local *local);
 
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 6cf121bebd7a..2e3adcb3ce23 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -138,9 +138,23 @@ static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
         ieee80211_debugfs_add_netdev(sdata);
 }
 
-void ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
-                              enum ieee80211_if_types type)
+int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
+                             enum ieee80211_if_types type)
 {
+        ASSERT_RTNL();
+
+        if (type == sdata->vif.type)
+                return 0;
+
+        /*
+         * We could, here, on changes between IBSS/STA/MESH modes,
+         * invoke an MLME function instead that disassociates etc.
+         * and goes into the requested mode.
+         */
+
+        if (netif_running(sdata->dev))
+                return -EBUSY;
+
         /* Purge and reset type-dependent state. */
         ieee80211_teardown_sdata(sdata->dev);
         ieee80211_setup_sdata(sdata, type);
@@ -149,6 +163,8 @@ void ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
         sdata->basic_rates = 0;
         sdata->drop_unencrypted = 0;
         sdata->sequence = 0;
+
+        return 0;
 }
 
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index f2fdd3342195..c041db9556c7 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -296,14 +296,7 @@ static int ieee80211_ioctl_siwmode(struct net_device *dev,
                 return -EINVAL;
         }
 
-        if (type == sdata->vif.type)
-                return 0;
-        if (netif_running(dev))
-                return -EBUSY;
-
-        ieee80211_if_change_type(sdata, type);
-
-        return 0;
+        return ieee80211_if_change_type(sdata, type);
 }