NetBSD/sys/compat/mach/mach_semaphore.c

294 lines
8.5 KiB
C

/* $NetBSD: mach_semaphore.c,v 1.5 2003/01/21 04:06:08 matt Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Emmanuel Dreyfus
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
__KERNEL_RCSID(0, "$NetBSD: mach_semaphore.c,v 1.5 2003/01/21 04:06:08 matt Exp $");
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/signal.h>
#include <sys/pool.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <compat/mach/mach_types.h>
#include <compat/mach/mach_message.h>
#include <compat/mach/mach_semaphore.h>
#include <compat/mach/mach_clock.h>
#include <compat/mach/mach_syscallargs.h>
/* Semaphore list, lock, pools */
static LIST_HEAD(mach_semaphore_list, mach_semaphore) mach_semaphore_list;
static struct lock mach_semaphore_list_lock;
static struct pool mach_semaphore_list_pool;
static struct pool mach_waiting_proc_pool;
/* Function to manipulate them */
static struct mach_semaphore *mach_semaphore_get(int, int);
static void mach_semaphore_put(struct mach_semaphore *);
static struct mach_waiting_proc *mach_waiting_proc_get
(struct proc *, struct mach_semaphore *);
static void mach_waiting_proc_put
(struct mach_waiting_proc *, struct mach_semaphore *, int);
int
mach_sys_semaphore_wait_trap(l, v, retval)
struct lwp *l;
void *v;
register_t *retval;
{
struct mach_sys_semaphore_wait_trap_args /* {
syscallarg(mach_port_name_t) wait_name;
} */ *uap = v;
struct mach_semaphore *ms;
struct mach_waiting_proc *mwp;
int blocked = 0;
ms = (struct mach_semaphore *)SCARG(uap, wait_name);
lockmgr(&ms->ms_lock, LK_EXCLUSIVE, NULL);
ms->ms_value--;
if (ms->ms_value < 0)
blocked = 1;
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
if (blocked != 0) {
mwp = mach_waiting_proc_get(l->l_proc, ms);
while (ms->ms_value < 0)
tsleep(mwp, PZERO|PCATCH, "sem_wait", 0);
mach_waiting_proc_put(mwp, ms, 0);
}
return 0;
}
int
mach_sys_semaphore_signal_trap(l, v, retval)
struct lwp *l;
void *v;
register_t *retval;
{
struct mach_sys_semaphore_signal_trap_args /* {
syscallarg(mach_port_name_t) signal_name;
} */ *uap = v;
struct mach_semaphore *ms;
struct mach_waiting_proc *mwp;
int unblocked = 0;
ms = (struct mach_semaphore *)SCARG(uap, signal_name);
lockmgr(&ms->ms_lock, LK_EXCLUSIVE, NULL);
ms->ms_value++;
if (ms->ms_value >= 0)
unblocked = 1;
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
if (unblocked != 0) {
lockmgr(&ms->ms_lock, LK_SHARED, NULL);
mwp = TAILQ_FIRST(&ms->ms_waiting);
wakeup(mwp);
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
}
return 0;
}
int
mach_semaphore_create(args)
struct mach_trap_args *args;
{
mach_semaphore_create_request_t *req = args->smsg;
mach_semaphore_create_reply_t *rep = args->rmsg;
size_t *msglen = args->rsize;
struct mach_semaphore *ms;
ms = mach_semaphore_get(req->req_value, req->req_policy);
rep->rep_msgh.msgh_bits =
MACH_MSGH_REPLY_LOCAL_BITS(MACH_MSG_TYPE_MOVE_SEND_ONCE);
rep->rep_msgh.msgh_size = sizeof(*rep) - sizeof(rep->rep_trailer);
rep->rep_msgh.msgh_local_port = req->req_msgh.msgh_local_port;
rep->rep_msgh.msgh_id = req->req_msgh.msgh_id + 100;
rep->rep_sem.name = (mach_port_t)ms; /* Waiting for better */
rep->rep_trailer.msgh_trailer_size = 8;
*msglen = sizeof(*rep);
return 0;
}
int
mach_semaphore_destroy(args)
struct mach_trap_args *args;
{
mach_semaphore_destroy_request_t *req = args->smsg;
mach_semaphore_destroy_reply_t *rep = args->rmsg;
size_t *msglen = args->rsize;
struct mach_semaphore *ms;
ms = (struct mach_semaphore *)req->req_sem.name;
mach_semaphore_put(ms);
rep->rep_msgh.msgh_bits =
MACH_MSGH_REPLY_LOCAL_BITS(MACH_MSG_TYPE_MOVE_SEND_ONCE);
rep->rep_msgh.msgh_size = sizeof(*rep) - sizeof(rep->rep_trailer);
rep->rep_msgh.msgh_local_port = req->req_msgh.msgh_local_port;
rep->rep_msgh.msgh_id = req->req_msgh.msgh_id + 100;
rep->rep_trailer.msgh_trailer_size = 8;
*msglen = sizeof(*rep);
return 0;
}
void
mach_semaphore_init(void)
{
LIST_INIT(&mach_semaphore_list);
lockinit(&mach_semaphore_list_lock, PZERO|PCATCH, "mach_sem", 0, 0);
pool_init(&mach_semaphore_list_pool, sizeof (struct mach_semaphore),
0, 0, 128, "mach_sem_pool", NULL);
pool_init(&mach_waiting_proc_pool, sizeof (struct mach_waiting_proc),
0, 0, 128, "mach_waitp_pool", NULL);
return;
}
static struct mach_semaphore *
mach_semaphore_get(value, policy)
int value;
int policy;
{
struct mach_semaphore *ms;
ms = (struct mach_semaphore *)pool_get(&mach_semaphore_list_pool,
M_WAITOK);
ms->ms_value = value;
ms->ms_policy = policy;
TAILQ_INIT(&ms->ms_waiting);
lockinit(&ms->ms_lock, PZERO|PCATCH, "mach_waitp", 0, 0);
lockmgr(&mach_semaphore_list_lock, LK_EXCLUSIVE, NULL);
LIST_INSERT_HEAD(&mach_semaphore_list, ms, ms_list);
lockmgr(&mach_semaphore_list_lock, LK_RELEASE, NULL);
return ms;
}
static void
mach_semaphore_put(ms)
struct mach_semaphore *ms;
{
struct mach_waiting_proc *mwp;
lockmgr(&ms->ms_lock, LK_EXCLUSIVE, NULL);
while ((mwp = TAILQ_FIRST(&ms->ms_waiting)) != NULL)
mach_waiting_proc_put(mwp, ms, 0);
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
lockmgr(&ms->ms_lock, LK_DRAIN, NULL);
lockmgr(&mach_semaphore_list_lock, LK_EXCLUSIVE, NULL);
LIST_REMOVE(ms, ms_list);
lockmgr(&mach_semaphore_list_lock, LK_RELEASE, NULL);
pool_put(&mach_semaphore_list_pool, ms);
return;
}
static struct mach_waiting_proc *
mach_waiting_proc_get(p, ms)
struct proc *p;
struct mach_semaphore *ms;
{
struct mach_waiting_proc *mwp;
mwp = (struct mach_waiting_proc *)pool_get(&mach_waiting_proc_pool,
M_WAITOK);
mwp->mwp_p = p;
lockmgr(&ms->ms_lock, LK_EXCLUSIVE, NULL);
TAILQ_INSERT_TAIL(&ms->ms_waiting, mwp, mwp_list);
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
return mwp;
}
static void
mach_waiting_proc_put(mwp, ms, locked)
struct mach_waiting_proc *mwp;
struct mach_semaphore *ms;
int locked;
{
if (!locked)
lockmgr(&ms->ms_lock, LK_EXCLUSIVE, NULL);
TAILQ_REMOVE(&ms->ms_waiting, mwp, mwp_list);
if (!locked)
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
pool_put(&mach_waiting_proc_pool, mwp);
return;
}
/*
* Cleanup after process exit. Need improvements, there
* can be some memory leaks here.
*/
void
mach_semaphore_cleanup(p)
struct proc *p;
{
struct mach_semaphore *ms;
struct mach_waiting_proc *mwp;
lockmgr(&mach_semaphore_list_lock, LK_SHARED, NULL);
LIST_FOREACH(ms, &mach_semaphore_list, ms_list) {
lockmgr(&ms->ms_lock, LK_SHARED, NULL);
TAILQ_FOREACH(mwp, &ms->ms_waiting, mwp_list)
if (mwp->mwp_p == p) {
lockmgr(&ms->ms_lock, LK_UPGRADE, NULL);
mach_waiting_proc_put(mwp, ms, 0);
ms->ms_value++;
if (ms->ms_value >= 0)
wakeup(TAILQ_FIRST(&ms->ms_waiting));
}
lockmgr(&ms->ms_lock, LK_RELEASE, NULL);
}
lockmgr(&mach_semaphore_list_lock, LK_RELEASE, NULL);
return;
}