cfg80211: allow the user space to change current NAN configuration

Some NAN configuration paramaters may change during the operation of
the NAN device. For example, a user may want to update master preference
value when the device gets plugged/unplugged to the power.
Add API that allows to do so.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 83 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 0eca59ccd685..c0b5ae4af2d8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -10919,6 +10919,40 @@ static int nl80211_nan_del_func(struct sk_buff *skb,
         return 0;
 }
 
+static int nl80211_nan_change_config(struct sk_buff *skb,
+                                     struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev = info->user_ptr[0];
+        struct wireless_dev *wdev = info->user_ptr[1];
+        struct cfg80211_nan_conf conf = {};
+        u32 changed = 0;
+
+        if (wdev->iftype != NL80211_IFTYPE_NAN)
+                return -EOPNOTSUPP;
+
+        if (!wdev->nan_started)
+                return -ENOTCONN;
+
+        if (info->attrs[NL80211_ATTR_NAN_MASTER_PREF]) {
+                conf.master_pref =
+                        nla_get_u8(info->attrs[NL80211_ATTR_NAN_MASTER_PREF]);
+                if (conf.master_pref <= 1 || conf.master_pref == 255)
+                        return -EINVAL;
+
+                changed |= CFG80211_NAN_CONF_CHANGED_PREF;
+        }
+
+        if (info->attrs[NL80211_ATTR_NAN_DUAL]) {
+                conf.dual = nla_get_u8(info->attrs[NL80211_ATTR_NAN_DUAL]);
+                changed |= CFG80211_NAN_CONF_CHANGED_DUAL;
+        }
+
+        if (!changed)
+                return -EINVAL;
+
+        return rdev_nan_change_conf(rdev, wdev, &conf, changed);
+}
+
 static int nl80211_get_protocol_features(struct sk_buff *skb,
                                          struct genl_info *info)
 {
@@ -12293,6 +12327,14 @@ static const struct genl_ops nl80211_ops[] = {
                                   NL80211_FLAG_NEED_RTNL,
         },
         {
+                .cmd = NL80211_CMD_CHANGE_NAN_CONFIG,
+                .doit = nl80211_nan_change_config,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+                .internal_flags = NL80211_FLAG_NEED_WDEV_UP |
+                                  NL80211_FLAG_NEED_RTNL,
+        },
+        {
                 .cmd = NL80211_CMD_SET_MCAST_RATE,
                 .doit = nl80211_set_mcast_rate,
                 .policy = nl80211_policy,
diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index 98c4c3bdcb11..11cf83c8ad4f 100644
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -928,6 +928,23 @@ static inline void rdev_del_nan_func(struct cfg80211_registered_device *rdev,
         trace_rdev_return_void(&rdev->wiphy);
 }
 
+static inline int
+rdev_nan_change_conf(struct cfg80211_registered_device *rdev,
+                     struct wireless_dev *wdev,
+                     struct cfg80211_nan_conf *conf, u32 changes)
+{
+        int ret;
+
+        trace_rdev_nan_change_conf(&rdev->wiphy, wdev, conf, changes);
+        if (rdev->ops->nan_change_conf)
+                ret = rdev->ops->nan_change_conf(&rdev->wiphy, wdev, conf,
+                                                 changes);
+        else
+                ret = -ENOTSUPP;
+        trace_rdev_return_int(&rdev->wiphy, ret);
+        return ret;
+}
+
 static inline int rdev_set_mac_acl(struct cfg80211_registered_device *rdev,
                                    struct net_device *dev,
                                    struct cfg80211_acl_data *params)
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 56089843d619..a3d0a91b1e09 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -1911,6 +1911,30 @@ TRACE_EVENT(rdev_start_nan,
                   __entry->dual)
 );
 
+TRACE_EVENT(rdev_nan_change_conf,
+        TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev,
+                 struct cfg80211_nan_conf *conf, u32 changes),
+        TP_ARGS(wiphy, wdev, conf, changes),
+        TP_STRUCT__entry(
+                WIPHY_ENTRY
+                WDEV_ENTRY
+                __field(u8, master_pref)
+                __field(u8, dual);
+                __field(u32, changes);
+        ),
+        TP_fast_assign(
+                WIPHY_ASSIGN;
+                WDEV_ASSIGN;
+                __entry->master_pref = conf->master_pref;
+                __entry->dual = conf->dual;
+                __entry->changes = changes;
+        ),
+        TP_printk(WIPHY_PR_FMT ", " WDEV_PR_FMT
+                  ", master preference: %u, dual: %d, changes: %x",
+                  WIPHY_PR_ARG, WDEV_PR_ARG, __entry->master_pref,
+                  __entry->dual, __entry->changes)
+);
+
 DEFINE_EVENT(wiphy_wdev_evt, rdev_stop_nan,
         TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev),
         TP_ARGS(wiphy, wdev)