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.sun.com/software/products/lustre/docs/GPLv2.pdf 19 * 20 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 21 * CA 95054 USA or visit www.sun.com if you need additional information or 22 * have any questions. 23 * 24 * GPL HEADER END 25 */ 26 /* 27 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved. 28 * Use is subject to license terms. 29 * 30 * Copyright (c) 2011, 2012, Intel Corporation. 31 */ 32 /* 33 * This file is part of Lustre, http://www.lustre.org/ 34 * Lustre is a trademark of Sun Microsystems, Inc. 35 */ 36 37 #ifndef __LUSTRE_HANDLES_H_ 38 #define __LUSTRE_HANDLES_H_ 39 40 /** \defgroup handles handles 41 * 42 * @{ 43 */ 44 45 #include <linux/atomic.h> 46 #include <linux/list.h> 47 #include <linux/rcupdate.h> 48 #include <linux/spinlock.h> 49 #include <linux/types.h> 50 51 #include "../../include/linux/libcfs/libcfs.h" 52 53 struct portals_handle_ops { 54 void (*hop_addref)(void *object); 55 void (*hop_free)(void *object, int size); 56 }; 57 58 /* These handles are most easily used by having them appear at the very top of 59 * whatever object that you want to make handles for. ie: 60 * 61 * struct ldlm_lock { 62 * struct portals_handle handle; 63 * ... 64 * }; 65 * 66 * Now you're able to assign the results of cookie2handle directly to an 67 * ldlm_lock. If it's not at the top, you'll want to use container_of() 68 * to compute the start of the structure based on the handle field. */ 69 struct portals_handle { 70 struct list_head h_link; 71 __u64 h_cookie; 72 struct portals_handle_ops *h_ops; 73 74 /* newly added fields to handle the RCU issue. -jxiong */ 75 struct rcu_head h_rcu; 76 spinlock_t h_lock; 77 unsigned int h_size:31; 78 unsigned int h_in:1; 79 }; 80 81 #define RCU2HANDLE(rcu) container_of(rcu, struct portals_handle, h_rcu) 82 83 /* handles.c */ 84 85 /* Add a handle to the hash table */ 86 void class_handle_hash(struct portals_handle *, 87 struct portals_handle_ops *ops); 88 void class_handle_unhash(struct portals_handle *); 89 void *class_handle2object(__u64 cookie); 90 void class_handle_free_cb(struct rcu_head *rcu); 91 int class_handle_init(void); 92 void class_handle_cleanup(void); 93 94 /** @} handles */ 95 96 #endif 97