/**
* @file
*
* @ingroup rtems_bsd_rtems
*
* @brief TODO.
*/
/*
* Copyright (c) 2011 OPTI Medical. All rights reserved.
*
* OPTI Medical
* 235 Hembree Park Drive
* Roswell, GA 30076
* USA
* <kevin.kirspel@optimedical.com>
*
* Copyright (c) 2013-2015 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* 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 <machine/rtems-bsd-kernel-space.h>
#include <machine/rtems-bsd-muteximpl.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#ifndef INVARIANTS
#define _rw_assert(rw, what, file, line)
#endif
static void assert_rw(const struct lock_object *lock, int what);
static void lock_rw(struct lock_object *lock, uintptr_t how);
static uintptr_t unlock_rw(struct lock_object *lock);
struct lock_class lock_class_rw = {
.lc_name = "rw",
.lc_flags = LC_SLEEPLOCK | LC_RECURSABLE | LC_UPGRADABLE,
.lc_assert = assert_rw,
.lc_lock = lock_rw,
.lc_unlock = unlock_rw,
};
#define rw_wowner(rw) rtems_bsd_mutex_owner(&(rw)->mutex)
#define rw_recursed(rw) rtems_bsd_mutex_recursed(&(rw)->mutex)
void
assert_rw(const struct lock_object *lock, int what)
{
rw_assert((const struct rwlock *)lock, what);
}
void
lock_rw(struct lock_object *lock, uintptr_t how)
{
rw_wlock((struct rwlock *)lock);
}
uintptr_t
unlock_rw(struct lock_object *lock)
{
rw_unlock((struct rwlock *)lock);
return (0);
}
void
rw_init_flags(struct rwlock *rw, const char *name, int opts)
{
int flags;
flags = LO_UPGRADABLE;
if (opts & RW_RECURSE)
flags |= LO_RECURSABLE;
rtems_bsd_mutex_init(&rw->lock_object, &rw->mutex, &lock_class_rw,
name, NULL, flags);
}
void
rw_destroy(struct rwlock *rw)
{
rtems_bsd_mutex_destroy(&rw->lock_object, &rw->mutex);
}
void
rw_sysinit(void *arg)
{
struct rw_args *args;
args = arg;
rw_init(args->ra_rw, args->ra_desc);
}
int
rw_wowned(struct rwlock *rw)
{
return (rtems_bsd_mutex_owned(&rw->mutex));
}
void
_rw_wlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_lock(&rw->lock_object, &rw->mutex);
}
int
_rw_try_wlock(struct rwlock *rw, const char *file, int line)
{
return (rtems_bsd_mutex_trylock(&rw->lock_object, &rw->mutex));
}
void
_rw_wunlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_unlock(&rw->mutex);
}
void
_rw_rlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_lock(&rw->lock_object, &rw->mutex);
}
int
_rw_try_rlock(struct rwlock *rw, const char *file, int line)
{
return (rtems_bsd_mutex_trylock(&rw->lock_object, &rw->mutex));
}
void
_rw_runlock(struct rwlock *rw, const char *file, int line)
{
rtems_bsd_mutex_unlock(&rw->mutex);
}
int
_rw_try_upgrade(struct rwlock *rw, const char *file, int line)
{
return (1);
}
void
_rw_downgrade(struct rwlock *rw, const char *file, int line)
{
/* Nothing to do */
}
#ifdef INVARIANT_SUPPORT
/*
* In the non-WITNESS case, rw_assert() can only detect that at least
* *some* thread owns an rlock, but it cannot guarantee that *this*
* thread owns an rlock.
*/
void
_rw_assert(const struct rwlock *rw, int what, const char *file, int line)
{
const char *name = rtems_bsd_mutex_name(&rw->mutex);
switch (what) {
case RA_LOCKED:
case RA_LOCKED | RA_RECURSED:
case RA_LOCKED | RA_NOTRECURSED:
case RA_RLOCKED:
case RA_RLOCKED | RA_RECURSED:
case RA_RLOCKED | RA_NOTRECURSED:
case RA_WLOCKED:
case RA_WLOCKED | RA_RECURSED:
case RA_WLOCKED | RA_NOTRECURSED:
if (rw_wowner(rw) != _Thread_Get_executing())
panic("Lock %s not exclusively locked @ %s:%d\n",
name, file, line);
if (rw_recursed(rw)) {
if (what & RA_NOTRECURSED)
panic("Lock %s recursed @ %s:%d\n", name, file,
line);
} else if (what & RA_RECURSED)
panic("Lock %s not recursed @ %s:%d\n", name, file,
line);
break;
case RA_UNLOCKED:
#ifdef WITNESS
witness_assert(&rw->lock_object, what, file, line);
#else
/*
* If we hold a write lock fail. We can't reliably check
* to see if we hold a read lock or not.
*/
if (rw_wowner(rw) == _Thread_Get_executing())
panic("Lock %s exclusively locked @ %s:%d\n", name,
file, line);
#endif
break;
default:
panic("Unknown rw lock assertion: %d @ %s:%d", what, file,
line);
}
}
#endif /* INVARIANT_SUPPORT */
