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37 #define DEBUG_SUBSYSTEM S_LDLM
38 #include <libcfs/libcfs.h>
40 #include <lustre_dlm.h>
41 #include <lustre_lib.h>
44 * Lock a lock and its resource.
46 * LDLM locking uses resource to serialize access to locks
47 * but there is a case when we change resource of lock upon
48 * enqueue reply. We rely on lock->l_resource = new_res
49 * being an atomic operation.
51 struct ldlm_resource *lock_res_and_lock(struct ldlm_lock *lock)
53 /* on server-side resource of lock doesn't change */
54 if (!ldlm_is_ns_srv(lock))
55 spin_lock(&lock->l_lock);
57 lock_res(lock->l_resource);
59 ldlm_set_res_locked(lock);
60 return lock->l_resource;
62 EXPORT_SYMBOL(lock_res_and_lock);
65 * Unlock a lock and its resource previously locked with lock_res_and_lock
67 void unlock_res_and_lock(struct ldlm_lock *lock)
69 /* on server-side resource of lock doesn't change */
70 ldlm_clear_res_locked(lock);
72 unlock_res(lock->l_resource);
73 if (!ldlm_is_ns_srv(lock))
74 spin_unlock(&lock->l_lock);
76 EXPORT_SYMBOL(unlock_res_and_lock);