mac80211: refactor channel switch function

The function was quite big. This splits out beacon
updating into a separate function for improved
maintenance and extension.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 63 insertions, 50 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 80534f524fd6..aaa59d719592 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -3089,52 +3089,11 @@ unlock:
         sdata_unlock(sdata);
 }
 
-int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
-                             struct cfg80211_csa_settings *params)
+static int ieee80211_set_csa_beacon(struct ieee80211_sub_if_data *sdata,
+                                    struct cfg80211_csa_settings *params,
+                                    u32 *changed)
 {
-        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-        struct ieee80211_local *local = sdata->local;
-        struct ieee80211_chanctx_conf *chanctx_conf;
-        struct ieee80211_chanctx *chanctx;
-        struct ieee80211_if_mesh __maybe_unused *ifmsh;
-        int err, num_chanctx, changed = 0;
-
-        sdata_assert_lock(sdata);
-
-        if (!list_empty(&local->roc_list) || local->scanning)
-                return -EBUSY;
-
-        if (sdata->wdev.cac_started)
-                return -EBUSY;
-
-        if (cfg80211_chandef_identical(&params->chandef,
-                                       &sdata->vif.bss_conf.chandef))
-                return -EINVAL;
-
-        rcu_read_lock();
-        chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
-        if (!chanctx_conf) {
-                rcu_read_unlock();
-                return -EBUSY;
-        }
-
-        /* don't handle for multi-VIF cases */
-        chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
-        if (chanctx->refcount > 1) {
-                rcu_read_unlock();
-                return -EBUSY;
-        }
-        num_chanctx = 0;
-        list_for_each_entry_rcu(chanctx, &local->chanctx_list, list)
-                num_chanctx++;
-        rcu_read_unlock();
-
-        if (num_chanctx > 1)
-                return -EBUSY;
-
-        /* don't allow another channel switch if one is already active. */
-        if (sdata->vif.csa_active)
-                return -EBUSY;
+        int err;
 
         switch (sdata->vif.type) {
         case NL80211_IFTYPE_AP:
@@ -3170,7 +3129,7 @@ int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
                         kfree(sdata->u.ap.next_beacon);
                         return err;
                 }
-                changed |= err;
+                *changed |= err;
 
                 break;
         case NL80211_IFTYPE_ADHOC:
@@ -3204,15 +3163,15 @@ int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
                         err = ieee80211_ibss_csa_beacon(sdata, params);
                         if (err < 0)
                                 return err;
-                        changed |= err;
+                        *changed |= err;
                 }
 
                 ieee80211_send_action_csa(sdata, params);
 
                 break;
 #ifdef CONFIG_MAC80211_MESH
-        case NL80211_IFTYPE_MESH_POINT:
-                ifmsh = &sdata->u.mesh;
+        case NL80211_IFTYPE_MESH_POINT: {
+                struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 
                 if (params->chandef.width != sdata->vif.bss_conf.chandef.width)
                         return -EINVAL;
@@ -3237,18 +3196,72 @@ int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
                                 ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
                                 return err;
                         }
-                        changed |= err;
+                        *changed |= err;
                 }
 
                 if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT)
                         ieee80211_send_action_csa(sdata, params);
 
                 break;
+                }
 #endif
         default:
                 return -EOPNOTSUPP;
         }
 
+        return 0;
+}
+
+int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,
+                             struct cfg80211_csa_settings *params)
+{
+        struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+        struct ieee80211_local *local = sdata->local;
+        struct ieee80211_chanctx_conf *chanctx_conf;
+        struct ieee80211_chanctx *chanctx;
+        int err, num_chanctx, changed = 0;
+
+        sdata_assert_lock(sdata);
+
+        if (!list_empty(&local->roc_list) || local->scanning)
+                return -EBUSY;
+
+        if (sdata->wdev.cac_started)
+                return -EBUSY;
+
+        if (cfg80211_chandef_identical(&params->chandef,
+                                       &sdata->vif.bss_conf.chandef))
+                return -EINVAL;
+
+        rcu_read_lock();
+        chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+        if (!chanctx_conf) {
+                rcu_read_unlock();
+                return -EBUSY;
+        }
+
+        /* don't handle for multi-VIF cases */
+        chanctx = container_of(chanctx_conf, struct ieee80211_chanctx, conf);
+        if (chanctx->refcount > 1) {
+                rcu_read_unlock();
+                return -EBUSY;
+        }
+        num_chanctx = 0;
+        list_for_each_entry_rcu(chanctx, &local->chanctx_list, list)
+                num_chanctx++;
+        rcu_read_unlock();
+
+        if (num_chanctx > 1)
+                return -EBUSY;
+
+        /* don't allow another channel switch if one is already active. */
+        if (sdata->vif.csa_active)
+                return -EBUSY;
+
+        err = ieee80211_set_csa_beacon(sdata, params, &changed);
+        if (err)
+                return err;
+
         sdata->csa_radar_required = params->radar_required;
 
         if (params->block_tx)