qcacld: Avoid race between IP notifier register unregister

Prima to qcacld-2.0 propagation

Avoid race condition between IP notifier registration and
de-registration by moving the registration out into the
initialization path.

Change-Id: Ieec17eb78748f0f901febb166c545fa06a2c2a1c
CRs-Fixed: 834529

3 files changed, 101 insertions, 57 deletions

diff --git a/CORE/HDD/inc/wlan_hdd_power.h b/CORE/HDD/inc/wlan_hdd_power.h
index 359d58017b2d..511db6f18594 100644
--- a/CORE/HDD/inc/wlan_hdd_power.h
+++ b/CORE/HDD/inc/wlan_hdd_power.h
@@ -96,4 +96,12 @@ VOS_STATUS hdd_conf_arp_offload(hdd_adapter_t* pAdapter, int fenable);
  *           either enable or disable them.
  */
 void hdd_conf_hostoffload(hdd_adapter_t * pAdapter, v_BOOL_t fenable);
+
+int wlan_hdd_ipv4_changed(struct notifier_block *nb,
+				unsigned long data, void *arg);
+
+int wlan_hdd_ipv6_changed(struct notifier_block *nb,
+				unsigned long data, void *arg);
+
+
 #endif // if !defined __WLAN_QCT_DRIVER_H
diff --git a/CORE/HDD/src/wlan_hdd_early_suspend.c b/CORE/HDD/src/wlan_hdd_early_suspend.c
index c53021714202..0bf2783e42f0 100644
--- a/CORE/HDD/src/wlan_hdd_early_suspend.c
+++ b/CORE/HDD/src/wlan_hdd_early_suspend.c
@@ -563,7 +563,12 @@ static int __wlan_hdd_ipv6_changed(struct notifier_block *nb,
             return NOTIFY_DONE;
         }
 
-        schedule_work(&pAdapter->ipv6NotifierWorkQueue);
+        if (pHddCtx->cfg_ini->nEnableSuspend ==
+                    WLAN_MAP_SUSPEND_TO_MCAST_BCAST_FILTER)
+             schedule_work(&pAdapter->ipv6NotifierWorkQueue);
+        else
+             hddLog(LOG1, FL("Not scheduling ipv6 wq nEnableSuspend = %d"),
+                              pHddCtx->cfg_ini->nEnableSuspend);
     }
 
     return NOTIFY_DONE;
@@ -581,7 +586,7 @@ static int __wlan_hdd_ipv6_changed(struct notifier_block *nb,
  *
  * Return: 0 on success, error number otherwise.
  */
-static int wlan_hdd_ipv6_changed(struct notifier_block *nb,
+int wlan_hdd_ipv6_changed(struct notifier_block *nb,
 				unsigned long data, void *arg)
 {
 	int ret;
@@ -619,7 +624,6 @@ static void hdd_conf_ns_offload(hdd_adapter_t *pAdapter, int fenable)
     hdd_context_t *pHddCtx;
 
     int i =0;
-    int ret =0;
     eHalStatus returnStatus;
 
     ENTER();
@@ -742,23 +746,6 @@ static void hdd_conf_ns_offload(hdd_adapter_t *pAdapter, int fenable)
                     vos_mem_zero(&offLoadRequest, sizeof(offLoadRequest));
                 }
             }
-            if (fenable == 1 && !pAdapter->ipv6_notifier_registered)
-            {
-                // Register IPv6 notifier to notify if any change in IP
-                // So that we can reconfigure the offload parameters
-                pAdapter->ipv6_notifier.notifier_call =
-                             wlan_hdd_ipv6_changed;
-                ret = register_inet6addr_notifier(&pAdapter->ipv6_notifier);
-                if (ret)
-                {
-                    hddLog(LOGE, FL("Failed to register IPv6 notifier"));
-                }
-                else
-                {
-                    hddLog(LOG1, FL("Registered IPv6 notifier"));
-                    pAdapter->ipv6_notifier_registered = true;
-                }
-            }
         }
         else
         {
@@ -770,12 +757,6 @@ static void hdd_conf_ns_offload(hdd_adapter_t *pAdapter, int fenable)
     else
     {
         //Disable NSOffload
-        if (pAdapter->ipv6_notifier_registered)
-        {
-            hddLog(LOG1, FL("Unregistered IPv6 notifier"));
-            unregister_inet6addr_notifier(&pAdapter->ipv6_notifier);
-            pAdapter->ipv6_notifier_registered = false;
-        }
         vos_mem_zero((void *)&offLoadRequest, sizeof(tSirHostOffloadReq));
         offLoadRequest.enableOrDisable = SIR_OFFLOAD_DISABLE;
         offLoadRequest.offloadType =  SIR_IPV6_NS_OFFLOAD;
@@ -796,7 +777,13 @@ static void hdd_conf_ns_offload(hdd_adapter_t *pAdapter, int fenable)
     return;
 }
 
-void hdd_ipv6_notifier_work_queue(struct work_struct *work)
+/**
+ * __hdd_ipv6_notifier_work_queue() - IP V6 change notifier work handler
+ * @work: Pointer to work context
+ *
+ * Return: none
+ */
+static void __hdd_ipv6_notifier_work_queue(struct work_struct *work)
 {
     hdd_adapter_t* pAdapter =
              container_of(work, hdd_adapter_t, ipv6NotifierWorkQueue);
@@ -824,12 +811,30 @@ void hdd_ipv6_notifier_work_queue(struct work_struct *work)
                 (WLAN_HDD_GET_STATION_CTX_PTR(pAdapter))->conn_info.connState)
         && (pHddCtx->hdd_wlan_suspended))
     {
-        // This invocation being part of the IPv6 registration callback,
-        // we are passing second parameter as 2 to avoid registration
-        // of IPv6 notifier again.
-        hdd_conf_ns_offload(pAdapter, 2);
+        /*
+         * This invocation being part of the IPv6 registration callback,
+         * we are passing second parameter as 2 to avoid registration
+         * of IPv6 notifier again
+         */
+        if (pHddCtx->cfg_ini->fhostNSOffload)
+            hdd_conf_ns_offload(pAdapter, 2);
     }
 }
+
+/**
+ * hdd_ipv6_notifier_work_queue() - IP V6 change notifier work handler
+ * @work: Pointer to work context
+ *
+ * Return: none
+ */
+void hdd_ipv6_notifier_work_queue(struct work_struct *work)
+{
+	vos_ssr_protect(__func__);
+	__hdd_ipv6_notifier_work_queue(work);
+	vos_ssr_unprotect(__func__);
+}
+
+
 #endif
 
 /*
@@ -963,7 +968,13 @@ void hdd_conf_hostoffload(hdd_adapter_t *pAdapter, v_BOOL_t fenable)
     return;
 }
 
-void hdd_ipv4_notifier_work_queue(struct work_struct *work)
+/**
+ * __hdd_ipv4_notifier_work_queue() - IP V4 change notifier work handler
+ * @work: Pointer to work context
+ *
+ * Return: none
+ */
+static void __hdd_ipv4_notifier_work_queue(struct work_struct *work)
 {
     hdd_adapter_t* pAdapter =
              container_of(work, hdd_adapter_t, ipv4NotifierWorkQueue);
@@ -997,6 +1008,19 @@ void hdd_ipv4_notifier_work_queue(struct work_struct *work)
     }
 }
 
+/**
+ * hdd_ipv4_notifier_work_queue() - IP V4 change notifier work handler
+ * @work: Pointer to work context
+ *
+ * Return: none
+ */
+void hdd_ipv4_notifier_work_queue(struct work_struct *work)
+{
+	vos_ssr_protect(__func__);
+	__hdd_ipv4_notifier_work_queue(work);
+	vos_ssr_unprotect(__func__);
+}
+
 static int __wlan_hdd_ipv4_changed(struct notifier_block *nb,
                                    unsigned long data, void *arg)
 {
@@ -1018,6 +1042,17 @@ static int __wlan_hdd_ipv4_changed(struct notifier_block *nb,
            hddLog(LOGE, FL("HDD context is invalid"));
            return NOTIFY_DONE;
        }
+
+       if ((pHddCtx->cfg_ini->nEnableSuspend !=
+             WLAN_MAP_SUSPEND_TO_MCAST_BCAST_FILTER) ||
+             (!pHddCtx->cfg_ini->fhostArpOffload)) {
+             hddLog(LOG1, FL("Offload not enabled MCBC=%d, ARPOffload=%d"),
+                            pHddCtx->cfg_ini->nEnableSuspend,
+                            pHddCtx->cfg_ini->fhostArpOffload);
+
+             return NOTIFY_DONE;
+       }
+
        if ((in_dev = __in_dev_get_rtnl(pAdapter->dev)) != NULL)
        {
            for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
@@ -1050,7 +1085,7 @@ static int __wlan_hdd_ipv4_changed(struct notifier_block *nb,
  *
  * Return: 0 on success, error number otherwise.
  */
-static int wlan_hdd_ipv4_changed(struct notifier_block *nb,
+int wlan_hdd_ipv4_changed(struct notifier_block *nb,
 				unsigned long data, void *arg)
 {
 	int ret;
@@ -1084,7 +1119,6 @@ VOS_STATUS hdd_conf_arp_offload(hdd_adapter_t *pAdapter, int fenable)
    struct in_ifaddr *ifa = NULL;
    struct in_device *in_dev;
    int i = 0;
-   int ret = 0;
    tSirHostOffloadReq  offLoadRequest;
    hdd_context_t *pHddCtx = WLAN_HDD_GET_CTX(pAdapter);
 
@@ -1161,33 +1195,10 @@ VOS_STATUS hdd_conf_arp_offload(hdd_adapter_t *pAdapter, int fenable)
            hddLog(VOS_TRACE_LEVEL_INFO, FL("IP Address is not assigned\n"));
        }
 
-       if (fenable == 1 && !pAdapter->ipv4_notifier_registered)
-       {
-           // Register IPv4 notifier to notify if any change in IP
-           // So that we can reconfigure the offload parameters
-           pAdapter->ipv4_notifier.notifier_call =
-                         wlan_hdd_ipv4_changed;
-           ret = register_inetaddr_notifier(&pAdapter->ipv4_notifier);
-           if (ret)
-           {
-               hddLog(LOGE, FL("Failed to register IPv4 notifier"));
-           }
-           else
-           {
-               hddLog(LOG1, FL("Registered IPv4 notifier"));
-               pAdapter->ipv4_notifier_registered = true;
-           }
-       }
        return VOS_STATUS_SUCCESS;
    }
    else
    {
-       if (pAdapter->ipv4_notifier_registered)
-       {
-            hddLog(LOG1, FL("Unregistered IPv4 notifier"));
-            unregister_inetaddr_notifier(&pAdapter->ipv4_notifier);
-            pAdapter->ipv4_notifier_registered = false;
-       }
        vos_mem_zero((void *)&offLoadRequest, sizeof(tSirHostOffloadReq));
        offLoadRequest.enableOrDisable = SIR_OFFLOAD_DISABLE;
        offLoadRequest.offloadType =  SIR_IPV4_ARP_REPLY_OFFLOAD;
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index 280ad81a43d8..ef235b3677e6 100755
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -8579,6 +8579,19 @@ hdd_adapter_t* hdd_open_adapter( hdd_context_t *pHddCtx, tANI_U8 session_type,
                    hdd_ipv4_notifier_work_queue);
 #endif
 
+         /*
+          * Register IPv4 notifier to notify if any change in IP
+          * So that we can reconfigure the offload parameters
+          */
+         pAdapter->ipv4_notifier.notifier_call = wlan_hdd_ipv4_changed;
+         ret = register_inetaddr_notifier(&pAdapter->ipv4_notifier);
+         if (ret) {
+               hddLog(LOGE, FL("Failed to register IPv4 notifier"));
+         } else {
+               hddLog(LOG1, FL("Registered IPv4 notifier"));
+               pAdapter->ipv4_notifier_registered = true;
+         }
+
 #ifdef WLAN_NS_OFFLOAD
          // Workqueue which gets scheduled in IPv6 notification callback.
 #ifdef CONFIG_CNSS
@@ -8588,6 +8601,18 @@ hdd_adapter_t* hdd_open_adapter( hdd_context_t *pHddCtx, tANI_U8 session_type,
          INIT_WORK(&pAdapter->ipv6NotifierWorkQueue,
                    hdd_ipv6_notifier_work_queue);
 #endif
+         /*
+          * Register IPv6 notifier to notify if any change in IP
+          * So that we can reconfigure the offload parameters
+          */
+          pAdapter->ipv6_notifier.notifier_call = wlan_hdd_ipv6_changed;
+          ret = register_inet6addr_notifier(&pAdapter->ipv6_notifier);
+          if (ret) {
+               hddLog(LOGE, FL("Failed to register IPv6 notifier"));
+          } else {
+               hddLog(LOG1, FL("Registered IPv6 notifier"));
+               pAdapter->ipv6_notifier_registered = true;
+          }
 #endif
          //Stop the Interface TX queue.
          hddLog(LOG1, FL("Disabling queues"));