[PATCH 2/2] mac80211: Support LIVE_ADDRESS_CHANGE feature

[James Prestwood]

Signed-off-by: James Prestwood <prest...@gmail.com>
---
 net/mac80211/iface.c | 51 ++++++++++++++++++++++++++++++++++++++++++--
 net/mac80211/main.c  |  1 +
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 8dc6580e1787..16ef6b83e7ea 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -198,15 +198,57 @@ static int ieee80211_verify_mac(struct 
ieee80211_sub_if_data *sdata, u8 *addr,
        return ret;
 }
 
+static int ieee80211_can_live_addr_change(struct ieee80211_sub_if_data *sdata)
+{
+       if (netif_carrier_ok(sdata->dev))
+               return -EBUSY;
+
+       switch (sdata->vif.type) {
+       case NL80211_IFTYPE_AP:
+       case NL80211_IFTYPE_P2P_GO:
+       case NL80211_IFTYPE_AP_VLAN:
+       case NL80211_IFTYPE_WDS:
+       case NL80211_IFTYPE_MESH_POINT:
+       case NL80211_IFTYPE_MONITOR:
+       case NL80211_IFTYPE_OCB:
+               /* No further checking required, when started or UP these
+                * interface types set carrier
+                */
+               break;
+       case NL80211_IFTYPE_ADHOC:
+               if (sdata->u.ibss.ssid_len != 0)
+                       return -EBUSY;
+               break;
+       case NL80211_IFTYPE_STATION:
+       case NL80211_IFTYPE_P2P_CLIENT:
+               if (!list_empty(&sdata->local->roc_list) ||
+                                       !sdata->local->scanning)
+                       return -EBUSY;
+               break;
+       default:
+               return -EOPNOTSUPP;
+       }
+
+       return 0;
+}
+
+
 static int ieee80211_change_mac(struct net_device *dev, void *addr)
 {
        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+       struct ieee80211_local *local = sdata->local;
        struct sockaddr *sa = addr;
        bool check_dup = true;
+       bool live = false;
        int ret;
 
-       if (ieee80211_sdata_running(sdata))
-               return -EBUSY;
+       if (ieee80211_sdata_running(sdata)) {
+               ret = ieee80211_can_live_addr_change(sdata);
+               if (ret)
+                       return ret;
+
+               live = true;
+       }
 
        if (sdata->vif.type == NL80211_IFTYPE_MONITOR &&
            !(sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE))
@@ -216,7 +258,11 @@ static int ieee80211_change_mac(struct net_device *dev, 
void *addr)
        if (ret)
                return ret;
 
+       if (live)
+               drv_remove_interface(local, sdata);
        ret = eth_mac_addr(dev, sa);
+       if (live)
+               drv_add_interface(local, sdata);
 
        if (ret == 0)
                memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);
@@ -1871,6 +1917,7 @@ int ieee80211_if_add(struct ieee80211_local *local, const 
char *name,
                        sdata->u.mgd.use_4addr = params->use_4addr;
 
                ndev->features |= local->hw.netdev_features;
+               ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 
                netdev_set_default_ethtool_ops(ndev, &ieee80211_ethtool_ops);
 
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 29b9d57df1a3..0aea583e5e69 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -596,6 +596,7 @@ struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t 
priv_data_len,
                wiphy_ext_feature_set(wiphy, NL80211_EXT_FEATURE_TXQS);
 
        wiphy_ext_feature_set(wiphy, NL80211_EXT_FEATURE_RRM);
+       wiphy_ext_feature_set(wiphy, NL80211_EXT_FEATURE_LIVE_ADDRESS_CHANGE);
 
        wiphy->bss_priv_size = sizeof(struct ieee80211_bss);
 
-- 
2.17.1