2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2000,2003 Doug Rabson
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/param.h>
30 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/mutex.h>
35 #include <sys/sysctl.h>
37 #include <sys/systm.h>
44 static MALLOC_DEFINE(M_KOBJ, "kobj", "Kernel object structures");
48 u_int kobj_lookup_hits;
49 u_int kobj_lookup_misses;
51 SYSCTL_UINT(_kern, OID_AUTO, kobj_hits, CTLFLAG_RD,
52 &kobj_lookup_hits, 0, "");
53 SYSCTL_UINT(_kern, OID_AUTO, kobj_misses, CTLFLAG_RD,
54 &kobj_lookup_misses, 0, "");
58 static struct mtx kobj_mtx;
59 static int kobj_mutex_inited;
60 static int kobj_next_id = 1;
62 #define KOBJ_LOCK() mtx_lock(&kobj_mtx)
63 #define KOBJ_UNLOCK() mtx_unlock(&kobj_mtx)
64 #define KOBJ_ASSERT(what) mtx_assert(&kobj_mtx, what);
66 SYSCTL_INT(_kern, OID_AUTO, kobj_methodcount, CTLFLAG_RD,
68 "Number of kernel object methods registered");
71 kobj_init_mutex(void *arg)
73 if (!kobj_mutex_inited) {
74 mtx_init(&kobj_mtx, "kobj", NULL, MTX_DEF);
75 kobj_mutex_inited = 1;
79 SYSINIT(kobj, SI_SUB_LOCK, SI_ORDER_ANY, kobj_init_mutex, NULL);
82 * This method structure is used to initialise new caches. Since the
83 * desc pointer is NULL, it is guaranteed never to match any read
86 static const struct kobj_method null_method = {
91 kobj_error_method(void)
98 kobj_class_compile_common(kobj_class_t cls, kobj_ops_t ops)
104 * Don't do anything if we are already compiled.
110 * First register any methods which need it.
112 for (m = cls->methods; m->desc; m++) {
113 if (m->desc->id == 0)
114 m->desc->id = kobj_next_id++;
118 * Then initialise the ops table.
120 for (i = 0; i < KOBJ_CACHE_SIZE; i++)
121 ops->cache[i] = &null_method;
127 kobj_class_compile1(kobj_class_t cls, int mflags)
131 KOBJ_ASSERT(MA_NOTOWNED);
133 ops = malloc(sizeof(struct kobj_ops), M_KOBJ, mflags);
138 * We may have lost a race for kobj_class_compile here - check
139 * to make sure someone else hasn't already compiled this
148 kobj_class_compile_common(cls, ops);
154 kobj_class_compile(kobj_class_t cls)
156 int error __diagused;
158 error = kobj_class_compile1(cls, M_WAITOK);
159 KASSERT(error == 0, ("kobj_class_compile1 returned %d", error));
163 kobj_class_compile_static(kobj_class_t cls, kobj_ops_t ops)
166 KASSERT(kobj_mutex_inited == 0,
167 ("%s: only supported during early cycles", __func__));
170 * Increment refs to make sure that the ops table is not freed.
173 kobj_class_compile_common(cls, ops);
176 static kobj_method_t*
177 kobj_lookup_method_class(kobj_class_t cls, kobjop_desc_t desc)
179 kobj_method_t *methods = cls->methods;
182 for (ce = methods; ce && ce->desc; ce++) {
183 if (ce->desc == desc) {
191 static kobj_method_t*
192 kobj_lookup_method_mi(kobj_class_t cls,
198 ce = kobj_lookup_method_class(cls, desc);
202 basep = cls->baseclasses;
204 for (; *basep; basep++) {
205 ce = kobj_lookup_method_mi(*basep, desc);
215 kobj_lookup_method(kobj_class_t cls,
221 ce = kobj_lookup_method_mi(cls, desc);
230 kobj_class_free(kobj_class_t cls)
234 KOBJ_ASSERT(MA_NOTOWNED);
238 * Protect against a race between kobj_create and
241 if (cls->refs == 0) {
243 * For now we don't do anything to unregister any methods
244 * which are no longer used.
248 * Free memory and clean up.
261 kobj_init_common(kobj_t obj, kobj_class_t cls)
269 kobj_init1(kobj_t obj, kobj_class_t cls, int mflags)
274 while (cls->ops == NULL) {
276 * kobj_class_compile doesn't want the lock held
277 * because of the call to malloc - we drop the lock
281 error = kobj_class_compile1(cls, mflags);
286 kobj_init_common(obj, cls);
292 kobj_create(kobj_class_t cls, struct malloc_type *mtype, int mflags)
296 obj = malloc(cls->size, mtype, mflags | M_ZERO);
299 if (kobj_init1(obj, cls, mflags) != 0) {
307 kobj_init(kobj_t obj, kobj_class_t cls)
311 error = kobj_init1(obj, cls, M_NOWAIT);
313 panic("kobj_init1 failed: error %d", error);
317 kobj_init_static(kobj_t obj, kobj_class_t cls)
320 KASSERT(kobj_mutex_inited == 0,
321 ("%s: only supported during early cycles", __func__));
323 kobj_init_common(obj, cls);
327 kobj_delete(kobj_t obj, struct malloc_type *mtype)
329 kobj_class_t cls = obj->ops->cls;
333 * Consider freeing the compiled method table for the class
334 * after its last instance is deleted. As an optimisation, we
335 * should defer this for a short while to avoid thrashing.
337 KOBJ_ASSERT(MA_NOTOWNED);
344 kobj_class_free(cls);