+struct ipc_namespace init_ipc_ns = {
+ .kref = {
+ .refcount = ATOMIC_INIT(2),
+ },
+};
+
+static struct ipc_namespace *clone_ipc_ns(struct ipc_namespace *old_ns)
+{
+ int err;
+ struct ipc_namespace *ns;
+
+ err = -ENOMEM;
+ ns = kmalloc(sizeof(struct ipc_namespace), GFP_KERNEL);
+ if (ns == NULL)
+ goto err_mem;
+
+ err = sem_init_ns(ns);
+ if (err)
+ goto err_sem;
+ err = msg_init_ns(ns);
+ if (err)
+ goto err_msg;
+ err = shm_init_ns(ns);
+ if (err)
+ goto err_shm;
+
+ kref_init(&ns->kref);
+ return ns;
+
+err_shm:
+ msg_exit_ns(ns);
+err_msg:
+ sem_exit_ns(ns);
+err_sem:
+ kfree(ns);
+err_mem:
+ return ERR_PTR(err);
+}
+
+struct ipc_namespace *copy_ipcs(unsigned long flags, struct ipc_namespace *ns)
+{
+ struct ipc_namespace *new_ns;
+
+ BUG_ON(!ns);
+ get_ipc_ns(ns);
+
+ if (!(flags & CLONE_NEWIPC))
+ return ns;
+
+ new_ns = clone_ipc_ns(ns);
+
+ put_ipc_ns(ns);
+ return new_ns;
+}
+
+void free_ipc_ns(struct kref *kref)
+{
+ struct ipc_namespace *ns;
+
+ ns = container_of(kref, struct ipc_namespace, kref);
+ sem_exit_ns(ns);
+ msg_exit_ns(ns);
+ shm_exit_ns(ns);
+ kfree(ns);
+}
+