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/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/mutex.h>
36 #include <sys/sysctl.h>
38 #include <sys/systm.h>
45 static MALLOC_DEFINE(M_KOBJ, "kobj", "Kernel object structures");
49 u_int kobj_lookup_hits;
50 u_int kobj_lookup_misses;
52 SYSCTL_UINT(_kern, OID_AUTO, kobj_hits, CTLFLAG_RD,
53 &kobj_lookup_hits, 0, "");
54 SYSCTL_UINT(_kern, OID_AUTO, kobj_misses, CTLFLAG_RD,
55 &kobj_lookup_misses, 0, "");
59 static struct mtx kobj_mtx;
60 static int kobj_mutex_inited;
61 static int kobj_next_id = 1;
63 #define KOBJ_LOCK() mtx_lock(&kobj_mtx)
64 #define KOBJ_UNLOCK() mtx_unlock(&kobj_mtx)
65 #define KOBJ_ASSERT(what) mtx_assert(&kobj_mtx, what);
67 SYSCTL_INT(_kern, OID_AUTO, kobj_methodcount, CTLFLAG_RD,
69 "Number of kernel object methods registered");
72 kobj_init_mutex(void *arg)
74 if (!kobj_mutex_inited) {
75 mtx_init(&kobj_mtx, "kobj", NULL, MTX_DEF);
76 kobj_mutex_inited = 1;
80 SYSINIT(kobj, SI_SUB_LOCK, SI_ORDER_ANY, kobj_init_mutex, NULL);
83 * This method structure is used to initialise new caches. Since the
84 * desc pointer is NULL, it is guaranteed never to match any read
87 static const struct kobj_method null_method = {
92 kobj_error_method(void)
99 kobj_class_compile_common(kobj_class_t cls, kobj_ops_t ops)
105 * Don't do anything if we are already compiled.
111 * First register any methods which need it.
113 for (i = 0, m = cls->methods; m->desc; i++, m++) {
114 if (m->desc->id == 0)
115 m->desc->id = kobj_next_id++;
119 * Then initialise the ops table.
121 for (i = 0; i < KOBJ_CACHE_SIZE; i++)
122 ops->cache[i] = &null_method;
128 kobj_class_compile1(kobj_class_t cls, int mflags)
132 KOBJ_ASSERT(MA_NOTOWNED);
134 ops = malloc(sizeof(struct kobj_ops), M_KOBJ, mflags);
139 * We may have lost a race for kobj_class_compile here - check
140 * to make sure someone else hasn't already compiled this
149 kobj_class_compile_common(cls, ops);
155 kobj_class_compile(kobj_class_t cls)
159 error = kobj_class_compile1(cls, M_WAITOK);
160 KASSERT(error == 0, ("kobj_class_compile1 returned %d", error));
164 kobj_class_compile_static(kobj_class_t cls, kobj_ops_t ops)
167 KASSERT(kobj_mutex_inited == 0,
168 ("%s: only supported during early cycles", __func__));
171 * Increment refs to make sure that the ops table is not freed.
174 kobj_class_compile_common(cls, ops);
177 static kobj_method_t*
178 kobj_lookup_method_class(kobj_class_t cls, kobjop_desc_t desc)
180 kobj_method_t *methods = cls->methods;
183 for (ce = methods; ce && ce->desc; ce++) {
184 if (ce->desc == desc) {
192 static kobj_method_t*
193 kobj_lookup_method_mi(kobj_class_t cls,
199 ce = kobj_lookup_method_class(cls, desc);
203 basep = cls->baseclasses;
205 for (; *basep; basep++) {
206 ce = kobj_lookup_method_mi(*basep, desc);
216 kobj_lookup_method(kobj_class_t cls,
222 ce = kobj_lookup_method_mi(cls, desc);
231 kobj_class_free(kobj_class_t cls)
235 KOBJ_ASSERT(MA_NOTOWNED);
239 * Protect against a race between kobj_create and
242 if (cls->refs == 0) {
244 * For now we don't do anything to unregister any methods
245 * which are no longer used.
249 * Free memory and clean up.
262 kobj_init_common(kobj_t obj, kobj_class_t cls)
270 kobj_init1(kobj_t obj, kobj_class_t cls, int mflags)
275 while (cls->ops == NULL) {
277 * kobj_class_compile doesn't want the lock held
278 * because of the call to malloc - we drop the lock
282 error = kobj_class_compile1(cls, mflags);
287 kobj_init_common(obj, cls);
293 kobj_create(kobj_class_t cls, struct malloc_type *mtype, int mflags)
297 obj = malloc(cls->size, mtype, mflags | M_ZERO);
300 if (kobj_init1(obj, cls, mflags) != 0) {
308 kobj_init(kobj_t obj, kobj_class_t cls)
312 error = kobj_init1(obj, cls, M_NOWAIT);
314 panic("kobj_init1 failed: error %d", error);
318 kobj_init_static(kobj_t obj, kobj_class_t cls)
321 KASSERT(kobj_mutex_inited == 0,
322 ("%s: only supported during early cycles", __func__));
324 kobj_init_common(obj, cls);
328 kobj_delete(kobj_t obj, struct malloc_type *mtype)
330 kobj_class_t cls = obj->ops->cls;
334 * Consider freeing the compiled method table for the class
335 * after its last instance is deleted. As an optimisation, we
336 * should defer this for a short while to avoid thrashing.
338 KOBJ_ASSERT(MA_NOTOWNED);
345 kobj_class_free(cls);