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/*-
* Copyright (c) 2000 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/errno.h>
#include <sys/sysctl.h>
#ifndef TEST
#include <sys/systm.h>
#endif
#include <sys/kobj.h>
#ifdef TEST
#include "usertest.h"
#endif
static MALLOC_DEFINE(M_KOBJ, "kobj", "Kernel object structures");
#ifdef KOBJ_STATS
u_int kobj_lookup_hits;
u_int kobj_lookup_misses;
SYSCTL_UINT(_kern, OID_AUTO, kobj_hits, CTLFLAG_RD,
&kobj_lookup_hits, 0, "");
SYSCTL_UINT(_kern, OID_AUTO, kobj_misses, CTLFLAG_RD,
&kobj_lookup_misses, 0, "");
#endif
static int kobj_next_id = 1;
SYSCTL_UINT(_kern, OID_AUTO, kobj_methodcount, CTLFLAG_RD,
&kobj_next_id, 0, "");
static int
kobj_error_method(void)
{
return ENXIO;
}
static void
kobj_register_method(struct kobjop_desc *desc)
{
if (desc->id == 0) {
KASSERT((kobj_next_id < KOBJ_CACHE_SIZE), ("kobj method table overflow"));
desc->id = kobj_next_id++;
}
}
static void
kobj_unregister_method(struct kobjop_desc *desc)
{
}
static void
kobj_class_compile_common(kobj_class_t cls, kobj_ops_t ops)
{
kobj_method_t *m;
int i;
/*
* Don't do anything if we are already compiled.
*/
if (cls->ops)
return;
/*
* First register any methods which need it.
*/
for (i = 0, m = cls->methods; m->desc; i++, m++)
kobj_register_method(m->desc);
/*
* Then initialise the ops table.
*/
bzero(ops, sizeof(struct kobj_ops));
ops->cls = cls;
cls->ops = ops;
}
void
kobj_class_compile(kobj_class_t cls)
{
kobj_ops_t ops;
/*
* Allocate space for the compiled ops table.
*/
ops = malloc(sizeof(struct kobj_ops), M_KOBJ, M_NOWAIT);
if (!ops)
panic("kobj_compile_methods: out of memory");
kobj_class_compile_common(cls, ops);
}
void
kobj_class_compile_static(kobj_class_t cls, kobj_ops_t ops)
{
/*
* Increment refs to make sure that the ops table is not freed.
*/
cls->refs++;
kobj_class_compile_common(cls, ops);
}
void
kobj_lookup_method(kobj_method_t *methods,
kobj_method_t *ce,
kobjop_desc_t desc)
{
ce->desc = desc;
for (; methods && methods->desc; methods++) {
if (methods->desc == desc) {
ce->func = methods->func;
return;
}
}
if (desc->deflt)
ce->func = desc->deflt;
else
ce->func = kobj_error_method;
return;
}
void
kobj_class_free(kobj_class_t cls)
{
int i;
kobj_method_t *m;
/*
* Unregister any methods which are no longer used.
*/
for (i = 0, m = cls->methods; m->desc; i++, m++)
kobj_unregister_method(m->desc);
/*
* Free memory and clean up.
*/
free(cls->ops, M_KOBJ);
cls->ops = 0;
}
kobj_t
kobj_create(kobj_class_t cls,
struct malloc_type *mtype,
int mflags)
{
kobj_t obj;
/*
* Allocate and initialise the new object.
*/
obj = malloc(cls->size, mtype, mflags | M_ZERO);
if (!obj)
return 0;
kobj_init(obj, cls);
return obj;
}
void
kobj_init(kobj_t obj, kobj_class_t cls)
{
/*
* Consider compiling the class' method table.
*/
if (!cls->ops)
kobj_class_compile(cls);
obj->ops = cls->ops;
cls->refs++;
}
void
kobj_delete(kobj_t obj, struct malloc_type *mtype)
{
kobj_class_t cls = obj->ops->cls;
/*
* Consider freeing the compiled method table for the class
* after its last instance is deleted. As an optimisation, we
* should defer this for a short while to avoid thrashing.
*/
cls->refs--;
if (!cls->refs)
kobj_class_free(cls);
obj->ops = 0;
if (mtype)
free(obj, mtype);
}
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