Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

[firefly-linux-kernel-4.4.55.git] / net / netfilter / ipvs / ip_vs_pe.c

diff --git a/net/netfilter/ipvs/ip_vs_pe.c b/net/netfilter/ipvs/ip_vs_pe.c
index 5cf859ccb31bbe096c9588643a9ed0f0d5f13342..1a82b29ce8eab833cc83f05ba032431442b1c70d 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_pe.c
+++ b/net/netfilter/ipvs/ip_vs_pe.c
@@ -13,20 +13,8 @@
 /* IPVS pe list */
 static LIST_HEAD(ip_vs_pe);
 
-/* lock for service table */
-static DEFINE_SPINLOCK(ip_vs_pe_lock);
-
-/* Bind a service with a pe */
-void ip_vs_bind_pe(struct ip_vs_service *svc, struct ip_vs_pe *pe)
-{
-       svc->pe = pe;
-}
-
-/* Unbind a service from its pe */
-void ip_vs_unbind_pe(struct ip_vs_service *svc)
-{
-       svc->pe = NULL;
-}
+/* semaphore for IPVS PEs. */
+static DEFINE_MUTEX(ip_vs_pe_mutex);
 
 /* Get pe in the pe list by name */
 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name)
@@ -36,9 +24,8 @@ struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name)
        IP_VS_DBG(10, "%s(): pe_name \"%s\"\n", __func__,
                  pe_name);
 
-       spin_lock_bh(&ip_vs_pe_lock);
-
-       list_for_each_entry(pe, &ip_vs_pe, n_list) {
+       rcu_read_lock();
+       list_for_each_entry_rcu(pe, &ip_vs_pe, n_list) {
                /* Test and get the modules atomically */
                if (pe->module &&
                    !try_module_get(pe->module)) {
@@ -47,14 +34,14 @@ struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name)
                }
                if (strcmp(pe_name, pe->name)==0) {
                        /* HIT */
-                       spin_unlock_bh(&ip_vs_pe_lock);
+                       rcu_read_unlock();
                        return pe;
                }
                if (pe->module)
                        module_put(pe->module);
        }
+       rcu_read_unlock();
 
-       spin_unlock_bh(&ip_vs_pe_lock);
        return NULL;
 }
 
@@ -83,22 +70,13 @@ int register_ip_vs_pe(struct ip_vs_pe *pe)
        /* increase the module use count */
        ip_vs_use_count_inc();
 
-       spin_lock_bh(&ip_vs_pe_lock);
-
-       if (!list_empty(&pe->n_list)) {
-               spin_unlock_bh(&ip_vs_pe_lock);
-               ip_vs_use_count_dec();
-               pr_err("%s(): [%s] pe already linked\n",
-                      __func__, pe->name);
-               return -EINVAL;
-       }
-
+       mutex_lock(&ip_vs_pe_mutex);
        /* Make sure that the pe with this name doesn't exist
         * in the pe list.
         */
        list_for_each_entry(tmp, &ip_vs_pe, n_list) {
                if (strcmp(tmp->name, pe->name) == 0) {
-                       spin_unlock_bh(&ip_vs_pe_lock);
+                       mutex_unlock(&ip_vs_pe_mutex);
                        ip_vs_use_count_dec();
                        pr_err("%s(): [%s] pe already existed "
                               "in the system\n", __func__, pe->name);
@@ -106,8 +84,8 @@ int register_ip_vs_pe(struct ip_vs_pe *pe)
                }
        }
        /* Add it into the d-linked pe list */
-       list_add(&pe->n_list, &ip_vs_pe);
-       spin_unlock_bh(&ip_vs_pe_lock);
+       list_add_rcu(&pe->n_list, &ip_vs_pe);
+       mutex_unlock(&ip_vs_pe_mutex);
 
        pr_info("[%s] pe registered.\n", pe->name);
 
@@ -118,17 +96,10 @@ EXPORT_SYMBOL_GPL(register_ip_vs_pe);
 /* Unregister a pe from the pe list */
 int unregister_ip_vs_pe(struct ip_vs_pe *pe)
 {
-       spin_lock_bh(&ip_vs_pe_lock);
-       if (list_empty(&pe->n_list)) {
-               spin_unlock_bh(&ip_vs_pe_lock);
-               pr_err("%s(): [%s] pe is not in the list. failed\n",
-                      __func__, pe->name);
-               return -EINVAL;
-       }
-
+       mutex_lock(&ip_vs_pe_mutex);
        /* Remove it from the d-linked pe list */
-       list_del(&pe->n_list);
-       spin_unlock_bh(&ip_vs_pe_lock);
+       list_del_rcu(&pe->n_list);
+       mutex_unlock(&ip_vs_pe_mutex);
 
        /* decrease the module use count */
        ip_vs_use_count_dec();