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34 * Implementation of cl_lock for VVP layer.
36 * Author: Nikita Danilov <nikita.danilov@sun.com>
39 #define DEBUG_SUBSYSTEM S_LLITE
42 # error This file is kernel only.
46 #include <lustre_lite.h>
48 #include "vvp_internal.h"
50 /*****************************************************************************
57 * Estimates lock value for the purpose of managing the lock cache during
60 * Locks for memory mapped files are almost infinitely precious, others are
61 * junk. "Mapped locks" are heavy, but not infinitely heavy, so that they are
62 * ordered within themselves by weights assigned from other layers.
64 static unsigned long vvp_lock_weigh(const struct lu_env *env,
65 const struct cl_lock_slice *slice)
67 struct ccc_object *cob = cl2ccc(slice->cls_obj);
70 RETURN(cfs_atomic_read(&cob->cob_mmap_cnt) > 0 ? ~0UL >> 2 : 0);
73 static const struct cl_lock_operations vvp_lock_ops = {
74 .clo_delete = ccc_lock_delete,
75 .clo_fini = ccc_lock_fini,
76 .clo_enqueue = ccc_lock_enqueue,
77 .clo_wait = ccc_lock_wait,
78 .clo_unuse = ccc_lock_unuse,
79 .clo_fits_into = ccc_lock_fits_into,
80 .clo_state = ccc_lock_state,
81 .clo_weigh = vvp_lock_weigh
84 int vvp_lock_init(const struct lu_env *env, struct cl_object *obj,
85 struct cl_lock *lock, const struct cl_io *io)
87 return ccc_lock_init(env, obj, lock, io, &vvp_lock_ops);