1 /* 2 * GPL HEADER START 3 * 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 only, 8 * as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License version 2 for more details (a copy is included 14 * in the LICENSE file that accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License 17 * version 2 along with this program; If not, see 18 * http://www.gnu.org/licenses/gpl-2.0.html 19 * 20 * GPL HEADER END 21 */ 22 /* 23 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. 24 * Use is subject to license terms. 25 * 26 * Copyright (c) 2012, Intel Corporation. 27 */ 28 /* 29 * This file is part of Lustre, http://www.lustre.org/ 30 * Lustre is a trademark of Sun Microsystems, Inc. 31 */ 32 33 #define DEBUG_SUBSYSTEM S_LDLM 34 #include <linux/libcfs/libcfs.h> 35 36 #include <lustre_dlm.h> 37 #include <lustre_lib.h> 38 39 /** 40 * Lock a lock and its resource. 41 * 42 * LDLM locking uses resource to serialize access to locks 43 * but there is a case when we change resource of lock upon 44 * enqueue reply. We rely on lock->l_resource = new_res 45 * being an atomic operation. 46 */ lock_res_and_lock(struct ldlm_lock * lock)47struct ldlm_resource *lock_res_and_lock(struct ldlm_lock *lock) 48 __acquires(&lock->l_lock) 49 __acquires(&lock->l_resource->lr_lock) 50 { 51 spin_lock(&lock->l_lock); 52 53 lock_res(lock->l_resource); 54 55 ldlm_set_res_locked(lock); 56 return lock->l_resource; 57 } 58 EXPORT_SYMBOL(lock_res_and_lock); 59 60 /** 61 * Unlock a lock and its resource previously locked with lock_res_and_lock 62 */ unlock_res_and_lock(struct ldlm_lock * lock)63void unlock_res_and_lock(struct ldlm_lock *lock) 64 __releases(&lock->l_resource->lr_lock) 65 __releases(&lock->l_lock) 66 { 67 /* on server-side resource of lock doesn't change */ 68 ldlm_clear_res_locked(lock); 69 70 unlock_res(lock->l_resource); 71 spin_unlock(&lock->l_lock); 72 } 73 EXPORT_SYMBOL(unlock_res_and_lock); 74