| /* |
| * GPL HEADER START |
| * |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 only, |
| * as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License version 2 for more details (a copy is included |
| * in the LICENSE file that accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License |
| * version 2 along with this program; If not, see |
| * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf |
| * |
| * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| * CA 95054 USA or visit www.sun.com if you need additional information or |
| * have any questions. |
| * |
| * GPL HEADER END |
| */ |
| /* |
| * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. |
| * Use is subject to license terms. |
| */ |
| /* |
| * This file is part of Lustre, http://www.lustre.org/ |
| * Lustre is a trademark of Sun Microsystems, Inc. |
| * |
| * Implementation of cl_lock for VVP layer. |
| * |
| * Author: Nikita Danilov <nikita.danilov@sun.com> |
| */ |
| |
| #define DEBUG_SUBSYSTEM S_LLITE |
| |
| |
| #include <obd.h> |
| #include <lustre_lite.h> |
| |
| #include "vvp_internal.h" |
| |
| /***************************************************************************** |
| * |
| * Vvp lock functions. |
| * |
| */ |
| |
| /** |
| * Estimates lock value for the purpose of managing the lock cache during |
| * memory shortages. |
| * |
| * Locks for memory mapped files are almost infinitely precious, others are |
| * junk. "Mapped locks" are heavy, but not infinitely heavy, so that they are |
| * ordered within themselves by weights assigned from other layers. |
| */ |
| static unsigned long vvp_lock_weigh(const struct lu_env *env, |
| const struct cl_lock_slice *slice) |
| { |
| struct ccc_object *cob = cl2ccc(slice->cls_obj); |
| |
| ENTRY; |
| RETURN(atomic_read(&cob->cob_mmap_cnt) > 0 ? ~0UL >> 2 : 0); |
| } |
| |
| static const struct cl_lock_operations vvp_lock_ops = { |
| .clo_delete = ccc_lock_delete, |
| .clo_fini = ccc_lock_fini, |
| .clo_enqueue = ccc_lock_enqueue, |
| .clo_wait = ccc_lock_wait, |
| .clo_unuse = ccc_lock_unuse, |
| .clo_fits_into = ccc_lock_fits_into, |
| .clo_state = ccc_lock_state, |
| .clo_weigh = vvp_lock_weigh |
| }; |
| |
| int vvp_lock_init(const struct lu_env *env, struct cl_object *obj, |
| struct cl_lock *lock, const struct cl_io *io) |
| { |
| return ccc_lock_init(env, obj, lock, io, &vvp_lock_ops); |
| } |