#include <linux/lustre_dlm.h>
#include <linux/lustre_lib.h>
+/*
+ * ldlm locking uses resource to serialize access to locks
+ * but there is a case when we change resource of lock upon
+ * enqueue reply. we rely on that lock->l_resource = new_res
+ * is atomic
+ */
+struct ldlm_resource * lock_res_and_lock(struct ldlm_lock *lock)
+{
+ struct ldlm_resource *res = lock->l_resource;
+
+ if (!res->lr_namespace->ns_client) {
+ /* on server-side resource of lock doesn't change */
+ lock_res(res);
+ return res;
+ }
+
+ lock_bitlock(lock);
+ res = lock->l_resource;
+ lock_res(res);
+ return res;
+}
+
+void unlock_res_and_lock(struct ldlm_lock *lock)
+{
+ struct ldlm_resource *res = lock->l_resource;
+
+ if (!res->lr_namespace->ns_client) {
+ /* on server-side resource of lock doesn't change */
+ unlock_res(res);
+ return;
+ }
+
+ unlock_res(res);
+ unlock_bitlock(lock);
+}
+