diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/llite/vvp_lock.c')
-rw-r--r-- | drivers/staging/lustre/lustre/llite/vvp_lock.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/llite/vvp_lock.c b/drivers/staging/lustre/lustre/llite/vvp_lock.c new file mode 100644 index 000000000000..9b8712bccd92 --- /dev/null +++ b/drivers/staging/lustre/lustre/llite/vvp_lock.c @@ -0,0 +1,85 @@ +/* + * 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); +} |