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authorSebastian Huber <sebastian.huber@embedded-brains.de>2013-10-09 22:42:09 +0200
committerSebastian Huber <sebastian.huber@embedded-brains.de>2013-10-10 09:06:58 +0200
commitbceabc95c1c85d793200446fa85f1ddc6313ea29 (patch)
tree973c8bd8deca9fd69913f2895cc91e0e6114d46c /freebsd/sys/kern/subr_kobj.c
parentAdd FreeBSD sources as a submodule (diff)
downloadrtems-libbsd-bceabc95c1c85d793200446fa85f1ddc6313ea29.tar.bz2
Move files to match FreeBSD layout
Diffstat (limited to 'freebsd/sys/kern/subr_kobj.c')
-rw-r--r--freebsd/sys/kern/subr_kobj.c363
1 files changed, 363 insertions, 0 deletions
diff --git a/freebsd/sys/kern/subr_kobj.c b/freebsd/sys/kern/subr_kobj.c
new file mode 100644
index 00000000..779fd905
--- /dev/null
+++ b/freebsd/sys/kern/subr_kobj.c
@@ -0,0 +1,363 @@
+#include <freebsd/machine/rtems-bsd-config.h>
+
+/*-
+ * Copyright (c) 2000,2003 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 <freebsd/sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <freebsd/sys/param.h>
+#include <freebsd/sys/kernel.h>
+#include <freebsd/sys/kobj.h>
+#include <freebsd/sys/lock.h>
+#include <freebsd/sys/malloc.h>
+#include <freebsd/sys/mutex.h>
+#include <freebsd/sys/sysctl.h>
+#ifndef TEST
+#include <freebsd/sys/systm.h>
+#endif
+
+#ifdef TEST
+#include <freebsd/local/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 struct mtx kobj_mtx;
+static int kobj_mutex_inited;
+static int kobj_next_id = 1;
+
+/*
+ * In the event that kobj_mtx has not been initialized yet,
+ * we will ignore it, and run without locks in order to support
+ * use of KOBJ before mutexes are available. This early in the boot
+ * process, everything is single threaded and so races should not
+ * happen. This is used to provide the PMAP layer on PowerPC, as well
+ * as board support.
+ */
+
+#define KOBJ_LOCK() if (kobj_mutex_inited) mtx_lock(&kobj_mtx);
+#define KOBJ_UNLOCK() if (kobj_mutex_inited) mtx_unlock(&kobj_mtx);
+#define KOBJ_ASSERT(what) if (kobj_mutex_inited) mtx_assert(&kobj_mtx,what);
+
+SYSCTL_UINT(_kern, OID_AUTO, kobj_methodcount, CTLFLAG_RD,
+ &kobj_next_id, 0, "");
+
+static void
+kobj_init_mutex(void *arg)
+{
+ if (!kobj_mutex_inited) {
+ mtx_init(&kobj_mtx, "kobj", NULL, MTX_DEF);
+ kobj_mutex_inited = 1;
+ }
+}
+
+SYSINIT(kobj, SI_SUB_LOCK, SI_ORDER_ANY, kobj_init_mutex, NULL);
+
+/*
+ * This method structure is used to initialise new caches. Since the
+ * desc pointer is NULL, it is guaranteed never to match any read
+ * descriptors.
+ */
+static struct kobj_method null_method = {
+ 0, 0,
+};
+
+int
+kobj_error_method(void)
+{
+
+ return ENXIO;
+}
+
+static void
+kobj_register_method(struct kobjop_desc *desc)
+{
+ KOBJ_ASSERT(MA_OWNED);
+
+ if (desc->id == 0) {
+ 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;
+
+ KOBJ_ASSERT(MA_OWNED);
+
+ /*
+ * 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.
+ */
+ for (i = 0; i < KOBJ_CACHE_SIZE; i++)
+ ops->cache[i] = &null_method;
+ ops->cls = cls;
+ cls->ops = ops;
+}
+
+void
+kobj_class_compile(kobj_class_t cls)
+{
+ kobj_ops_t ops;
+
+ KOBJ_ASSERT(MA_NOTOWNED);
+
+ /*
+ * 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_LOCK();
+
+ /*
+ * We may have lost a race for kobj_class_compile here - check
+ * to make sure someone else hasn't already compiled this
+ * class.
+ */
+ if (cls->ops) {
+ KOBJ_UNLOCK();
+ free(ops, M_KOBJ);
+ return;
+ }
+
+ kobj_class_compile_common(cls, ops);
+ KOBJ_UNLOCK();
+}
+
+void
+kobj_class_compile_static(kobj_class_t cls, kobj_ops_t ops)
+{
+
+ KOBJ_ASSERT(MA_NOTOWNED);
+
+ /*
+ * Increment refs to make sure that the ops table is not freed.
+ */
+ KOBJ_LOCK();
+
+ cls->refs++;
+ kobj_class_compile_common(cls, ops);
+
+ KOBJ_UNLOCK();
+}
+
+static kobj_method_t*
+kobj_lookup_method_class(kobj_class_t cls, kobjop_desc_t desc)
+{
+ kobj_method_t *methods = cls->methods;
+ kobj_method_t *ce;
+
+ for (ce = methods; ce && ce->desc; ce++) {
+ if (ce->desc == desc) {
+ return ce;
+ }
+ }
+
+ return NULL;
+}
+
+static kobj_method_t*
+kobj_lookup_method_mi(kobj_class_t cls,
+ kobjop_desc_t desc)
+{
+ kobj_method_t *ce;
+ kobj_class_t *basep;
+
+ ce = kobj_lookup_method_class(cls, desc);
+ if (ce)
+ return ce;
+
+ basep = cls->baseclasses;
+ if (basep) {
+ for (; *basep; basep++) {
+ ce = kobj_lookup_method_mi(*basep, desc);
+ if (ce)
+ return ce;
+ }
+ }
+
+ return NULL;
+}
+
+kobj_method_t*
+kobj_lookup_method(kobj_class_t cls,
+ kobj_method_t **cep,
+ kobjop_desc_t desc)
+{
+ kobj_method_t *ce;
+
+#ifdef KOBJ_STATS
+ /*
+ * Correct for the 'hit' assumption in KOBJOPLOOKUP and record
+ * a 'miss'.
+ */
+ kobj_lookup_hits--;
+ kobj_lookup_misses++;
+#endif
+
+ ce = kobj_lookup_method_mi(cls, desc);
+ if (!ce)
+ ce = desc->deflt;
+ *cep = ce;
+ return ce;
+}
+
+void
+kobj_class_free(kobj_class_t cls)
+{
+ int i;
+ kobj_method_t *m;
+ void* ops = NULL;
+
+ KOBJ_ASSERT(MA_NOTOWNED);
+ KOBJ_LOCK();
+
+ /*
+ * Protect against a race between kobj_create and
+ * kobj_delete.
+ */
+ if (cls->refs == 0) {
+ /*
+ * 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.
+ */
+ ops = cls->ops;
+ cls->ops = NULL;
+ }
+
+ KOBJ_UNLOCK();
+
+ if (ops)
+ free(ops, M_KOBJ);
+}
+
+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 NULL;
+ kobj_init(obj, cls);
+
+ return obj;
+}
+
+void
+kobj_init(kobj_t obj, kobj_class_t cls)
+{
+ KOBJ_ASSERT(MA_NOTOWNED);
+ retry:
+ KOBJ_LOCK();
+
+ /*
+ * Consider compiling the class' method table.
+ */
+ if (!cls->ops) {
+ /*
+ * kobj_class_compile doesn't want the lock held
+ * because of the call to malloc - we drop the lock
+ * and re-try.
+ */
+ KOBJ_UNLOCK();
+ kobj_class_compile(cls);
+ goto retry;
+ }
+
+ obj->ops = cls->ops;
+ cls->refs++;
+
+ KOBJ_UNLOCK();
+}
+
+void
+kobj_delete(kobj_t obj, struct malloc_type *mtype)
+{
+ kobj_class_t cls = obj->ops->cls;
+ int refs;
+
+ /*
+ * 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.
+ */
+ KOBJ_ASSERT(MA_NOTOWNED);
+ KOBJ_LOCK();
+ cls->refs--;
+ refs = cls->refs;
+ KOBJ_UNLOCK();
+
+ if (!refs)
+ kobj_class_free(cls);
+
+ obj->ops = NULL;
+ if (mtype)
+ free(obj, mtype);
+}