mac80211: use RCU_INIT_POINTER
rcu_assign_pointer() ensures that the initialization of a structure is
carried out before storing a pointer to that structure. However, in the
case that NULL is assigned there's no structure to initialize so using
RCU_INIT_POINTER instead is safe and more efficient.
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
[squash eight tiny patches, rewrite commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index aaa59d7..906bc3b 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1566,7 +1566,7 @@
if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
sta->sdata->u.vlan.sta) {
- rcu_assign_pointer(sta->sdata->u.vlan.sta, NULL);
+ RCU_INIT_POINTER(sta->sdata->u.vlan.sta, NULL);
prev_4addr = true;
}
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index bd1fd8e..b297bd3 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -392,7 +392,7 @@
lockdep_assert_held(&local->chanctx_mtx);
ctx->refcount--;
- rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
+ RCU_INIT_POINTER(sdata->vif.chanctx_conf, NULL);
sdata->vif.bss_conf.idle = true;
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index fa16e54..0e963bc 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -128,7 +128,7 @@
if (!strcmp(buf, TX_LATENCY_DISABLED)) {
if (!tx_latency)
goto unlock;
- rcu_assign_pointer(local->tx_latency, NULL);
+ RCU_INIT_POINTER(local->tx_latency, NULL);
synchronize_rcu();
kfree(tx_latency);
goto unlock;
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 06d2878..35e4f94 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -253,7 +253,7 @@
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
- rcu_assign_pointer(ifibss->presp, NULL);
+ RCU_INIT_POINTER(ifibss->presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index b8d331e..4826c8f 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -423,7 +423,7 @@
mutex_unlock(&local->mtx);
if (ret) {
mutex_lock(&local->iflist_mtx);
- rcu_assign_pointer(local->monitor_sdata, NULL);
+ RCU_INIT_POINTER(local->monitor_sdata, NULL);
mutex_unlock(&local->iflist_mtx);
synchronize_net();
drv_remove_interface(local, sdata);
@@ -452,7 +452,7 @@
return;
}
- rcu_assign_pointer(local->monitor_sdata, NULL);
+ RCU_INIT_POINTER(local->monitor_sdata, NULL);
mutex_unlock(&local->iflist_mtx);
synchronize_net();
@@ -876,7 +876,7 @@
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
list_del(&sdata->u.vlan.list);
- rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
+ RCU_INIT_POINTER(sdata->vif.chanctx_conf, NULL);
/* no need to tell driver */
break;
case NL80211_IFTYPE_MONITOR:
@@ -895,7 +895,7 @@
break;
case NL80211_IFTYPE_P2P_DEVICE:
/* relies on synchronize_rcu() below */
- rcu_assign_pointer(local->p2p_sdata, NULL);
+ RCU_INIT_POINTER(local->p2p_sdata, NULL);
/* fall through */
default:
cancel_work_sync(&sdata->work);
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index f70e9cd..387f61c 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -829,7 +829,7 @@
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
bcn = rcu_dereference_protected(ifmsh->beacon,
lockdep_is_held(&sdata->wdev.mtx));
- rcu_assign_pointer(ifmsh->beacon, NULL);
+ RCU_INIT_POINTER(ifmsh->beacon, NULL);
kfree_rcu(bcn, rcu_head);
/* flush STAs and mpaths on this iface */
@@ -1068,7 +1068,7 @@
/* Remove the CSA and MCSP elements from the beacon */
tmp_csa_settings = rcu_dereference(ifmsh->csa);
- rcu_assign_pointer(ifmsh->csa, NULL);
+ RCU_INIT_POINTER(ifmsh->csa, NULL);
if (tmp_csa_settings)
kfree_rcu(tmp_csa_settings, rcu_head);
ret = ieee80211_mesh_rebuild_beacon(sdata);
@@ -1102,7 +1102,7 @@
ret = ieee80211_mesh_rebuild_beacon(sdata);
if (ret) {
tmp_csa_settings = rcu_dereference(ifmsh->csa);
- rcu_assign_pointer(ifmsh->csa, NULL);
+ RCU_INIT_POINTER(ifmsh->csa, NULL);
kfree_rcu(tmp_csa_settings, rcu_head);
return ret;
}
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 3ce7f2c..28185c8 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -309,7 +309,7 @@
if (local->scan_req != local->int_scan_req)
cfg80211_scan_done(local->scan_req, aborted);
local->scan_req = NULL;
- rcu_assign_pointer(local->scan_sdata, NULL);
+ RCU_INIT_POINTER(local->scan_sdata, NULL);
local->scanning = 0;
local->scan_chandef.chan = NULL;
@@ -559,7 +559,7 @@
ieee80211_recalc_idle(local);
local->scan_req = NULL;
- rcu_assign_pointer(local->scan_sdata, NULL);
+ RCU_INIT_POINTER(local->scan_sdata, NULL);
}
return rc;
@@ -773,7 +773,7 @@
int rc;
local->scan_req = NULL;
- rcu_assign_pointer(local->scan_sdata, NULL);
+ RCU_INIT_POINTER(local->scan_sdata, NULL);
rc = __ieee80211_start_scan(sdata, req);
if (rc) {
@@ -1014,7 +1014,7 @@
if (ret) {
/* Clean in case of failure after HW restart or upon resume. */
- rcu_assign_pointer(local->sched_scan_sdata, NULL);
+ RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
local->sched_scan_req = NULL;
}
@@ -1089,7 +1089,7 @@
return;
}
- rcu_assign_pointer(local->sched_scan_sdata, NULL);
+ RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
/* If sched scan was aborted by the driver. */
local->sched_scan_req = NULL;
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 5cf62ec..73af739 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1546,7 +1546,7 @@
WARN_ON(local->resuming);
res = drv_add_interface(local, sdata);
if (WARN_ON(res)) {
- rcu_assign_pointer(local->monitor_sdata, NULL);
+ RCU_INIT_POINTER(local->monitor_sdata, NULL);
synchronize_net();
kfree(sdata);
}