e97eae1577
This means that their use is restricted to a single C file.
611 lines
14 KiB
C
611 lines
14 KiB
C
/*-
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* Copyright (c) 2000 Michael Smith
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* Copyright (c) 2000 BSDi
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* Copyright (c) 2007-2009 Jung-uk Kim <jkim@FreeBSD.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* 6.1 : Mutual Exclusion and Synchronisation
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <contrib/dev/acpica/include/acpi.h>
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#include <contrib/dev/acpica/include/accommon.h>
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#include <sys/condvar.h>
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#include <sys/kernel.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#include <sys/mutex.h>
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#define _COMPONENT ACPI_OS_SERVICES
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ACPI_MODULE_NAME("SYNCH")
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static MALLOC_DEFINE(M_ACPISEM, "acpisem", "ACPI semaphore");
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/*
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* Convert milliseconds to ticks.
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*/
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static int
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timeout2hz(UINT16 Timeout)
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{
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struct timeval tv;
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tv.tv_sec = (time_t)(Timeout / 1000);
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tv.tv_usec = (suseconds_t)(Timeout % 1000) * 1000;
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return (tvtohz(&tv));
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}
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/*
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* ACPI_SEMAPHORE
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*/
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struct acpi_sema {
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struct mtx as_lock;
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char as_name[32];
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struct cv as_cv;
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UINT32 as_maxunits;
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UINT32 as_units;
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int as_waiters;
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int as_reset;
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};
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ACPI_STATUS
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AcpiOsCreateSemaphore(UINT32 MaxUnits, UINT32 InitialUnits,
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ACPI_SEMAPHORE *OutHandle)
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{
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struct acpi_sema *as;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (OutHandle == NULL || MaxUnits == 0 || InitialUnits > MaxUnits)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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if ((as = malloc(sizeof(*as), M_ACPISEM, M_NOWAIT | M_ZERO)) == NULL)
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return_ACPI_STATUS (AE_NO_MEMORY);
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snprintf(as->as_name, sizeof(as->as_name), "ACPI sema (%p)", as);
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mtx_init(&as->as_lock, as->as_name, NULL, MTX_DEF);
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cv_init(&as->as_cv, as->as_name);
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as->as_maxunits = MaxUnits;
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as->as_units = InitialUnits;
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*OutHandle = (ACPI_SEMAPHORE)as;
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "created %s, max %u, initial %u\n",
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as->as_name, MaxUnits, InitialUnits));
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return_ACPI_STATUS (AE_OK);
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}
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ACPI_STATUS
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AcpiOsDeleteSemaphore(ACPI_SEMAPHORE Handle)
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{
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struct acpi_sema *as = (struct acpi_sema *)Handle;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (as == NULL)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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mtx_lock(&as->as_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "delete %s\n", as->as_name));
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if (as->as_waiters > 0) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"reset %s, units %u, waiters %d\n",
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as->as_name, as->as_units, as->as_waiters));
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as->as_reset = 1;
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cv_broadcast(&as->as_cv);
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while (as->as_waiters > 0) {
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if (mtx_sleep(&as->as_reset, &as->as_lock,
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PCATCH, "acsrst", hz) == EINTR) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"failed to reset %s, waiters %d\n",
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as->as_name, as->as_waiters));
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mtx_unlock(&as->as_lock);
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return_ACPI_STATUS (AE_ERROR);
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}
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"wait %s, units %u, waiters %d\n",
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as->as_name, as->as_units, as->as_waiters));
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}
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}
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mtx_unlock(&as->as_lock);
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mtx_destroy(&as->as_lock);
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cv_destroy(&as->as_cv);
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free(as, M_ACPISEM);
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return_ACPI_STATUS (AE_OK);
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}
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#define ACPISEM_AVAIL(s, u) ((s)->as_units >= (u))
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ACPI_STATUS
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AcpiOsWaitSemaphore(ACPI_SEMAPHORE Handle, UINT32 Units, UINT16 Timeout)
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{
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struct acpi_sema *as = (struct acpi_sema *)Handle;
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int error, prevtick, slptick, tmo;
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ACPI_STATUS status = AE_OK;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (as == NULL || Units == 0)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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mtx_lock(&as->as_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"get %u unit(s) from %s, units %u, waiters %d, timeout %u\n",
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Units, as->as_name, as->as_units, as->as_waiters, Timeout));
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if (as->as_maxunits != ACPI_NO_UNIT_LIMIT && as->as_maxunits < Units) {
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mtx_unlock(&as->as_lock);
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return_ACPI_STATUS (AE_LIMIT);
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}
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switch (Timeout) {
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case ACPI_DO_NOT_WAIT:
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if (!ACPISEM_AVAIL(as, Units))
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status = AE_TIME;
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break;
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case ACPI_WAIT_FOREVER:
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while (!ACPISEM_AVAIL(as, Units)) {
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as->as_waiters++;
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error = cv_wait_sig(&as->as_cv, &as->as_lock);
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as->as_waiters--;
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if (error == EINTR || as->as_reset) {
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status = AE_ERROR;
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break;
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}
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}
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break;
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default:
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tmo = timeout2hz(Timeout);
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while (!ACPISEM_AVAIL(as, Units)) {
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prevtick = ticks;
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as->as_waiters++;
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error = cv_timedwait_sig(&as->as_cv, &as->as_lock, tmo);
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as->as_waiters--;
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if (error == EINTR || as->as_reset) {
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status = AE_ERROR;
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break;
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}
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if (ACPISEM_AVAIL(as, Units))
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break;
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slptick = ticks - prevtick;
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if (slptick >= tmo || slptick < 0) {
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status = AE_TIME;
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break;
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}
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tmo -= slptick;
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}
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}
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if (status == AE_OK)
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as->as_units -= Units;
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mtx_unlock(&as->as_lock);
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return_ACPI_STATUS (status);
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}
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ACPI_STATUS
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AcpiOsSignalSemaphore(ACPI_SEMAPHORE Handle, UINT32 Units)
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{
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struct acpi_sema *as = (struct acpi_sema *)Handle;
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UINT32 i;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (as == NULL || Units == 0)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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mtx_lock(&as->as_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"return %u units to %s, units %u, waiters %d\n",
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Units, as->as_name, as->as_units, as->as_waiters));
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if (as->as_maxunits != ACPI_NO_UNIT_LIMIT &&
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(as->as_maxunits < Units ||
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as->as_maxunits - Units < as->as_units)) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"exceeded max units %u\n", as->as_maxunits));
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mtx_unlock(&as->as_lock);
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return_ACPI_STATUS (AE_LIMIT);
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}
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as->as_units += Units;
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if (as->as_waiters > 0 && ACPISEM_AVAIL(as, Units))
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for (i = 0; i < Units; i++)
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cv_signal(&as->as_cv);
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mtx_unlock(&as->as_lock);
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return_ACPI_STATUS (AE_OK);
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}
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#undef ACPISEM_AVAIL
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/*
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* ACPI_MUTEX
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*/
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struct acpi_mutex {
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struct mtx am_lock;
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char am_name[32];
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struct thread *am_owner;
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int am_nested;
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int am_waiters;
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int am_reset;
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};
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ACPI_STATUS
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AcpiOsCreateMutex(ACPI_MUTEX *OutHandle)
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{
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struct acpi_mutex *am;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (OutHandle == NULL)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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if ((am = malloc(sizeof(*am), M_ACPISEM, M_NOWAIT | M_ZERO)) == NULL)
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return_ACPI_STATUS (AE_NO_MEMORY);
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snprintf(am->am_name, sizeof(am->am_name), "ACPI mutex (%p)", am);
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mtx_init(&am->am_lock, am->am_name, NULL, MTX_DEF);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "created %s\n", am->am_name));
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*OutHandle = (ACPI_MUTEX)am;
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return_ACPI_STATUS (AE_OK);
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}
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#define ACPIMTX_AVAIL(m) ((m)->am_owner == NULL)
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#define ACPIMTX_OWNED(m) ((m)->am_owner == curthread)
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void
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AcpiOsDeleteMutex(ACPI_MUTEX Handle)
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{
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struct acpi_mutex *am = (struct acpi_mutex *)Handle;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (am == NULL) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "cannot delete null mutex\n"));
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return_VOID;
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}
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mtx_lock(&am->am_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "delete %s\n", am->am_name));
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if (am->am_waiters > 0) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"reset %s, owner %p\n", am->am_name, am->am_owner));
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am->am_reset = 1;
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wakeup(am);
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while (am->am_waiters > 0) {
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if (mtx_sleep(&am->am_reset, &am->am_lock,
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PCATCH, "acmrst", hz) == EINTR) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"failed to reset %s, waiters %d\n",
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am->am_name, am->am_waiters));
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mtx_unlock(&am->am_lock);
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return_VOID;
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}
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if (ACPIMTX_AVAIL(am))
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"wait %s, waiters %d\n",
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am->am_name, am->am_waiters));
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else
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"wait %s, owner %p, waiters %d\n",
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am->am_name, am->am_owner, am->am_waiters));
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}
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}
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mtx_unlock(&am->am_lock);
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mtx_destroy(&am->am_lock);
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free(am, M_ACPISEM);
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}
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ACPI_STATUS
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AcpiOsAcquireMutex(ACPI_MUTEX Handle, UINT16 Timeout)
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{
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struct acpi_mutex *am = (struct acpi_mutex *)Handle;
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int error, prevtick, slptick, tmo;
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ACPI_STATUS status = AE_OK;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (am == NULL)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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mtx_lock(&am->am_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "acquire %s\n", am->am_name));
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if (ACPIMTX_OWNED(am)) {
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am->am_nested++;
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"acquire nested %s, depth %d\n",
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am->am_name, am->am_nested));
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mtx_unlock(&am->am_lock);
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return_ACPI_STATUS (AE_OK);
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}
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switch (Timeout) {
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case ACPI_DO_NOT_WAIT:
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if (!ACPIMTX_AVAIL(am))
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status = AE_TIME;
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break;
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case ACPI_WAIT_FOREVER:
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while (!ACPIMTX_AVAIL(am)) {
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am->am_waiters++;
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error = mtx_sleep(am, &am->am_lock, PCATCH, "acmtx", 0);
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am->am_waiters--;
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if (error == EINTR || am->am_reset) {
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status = AE_ERROR;
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break;
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}
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}
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break;
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default:
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tmo = timeout2hz(Timeout);
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while (!ACPIMTX_AVAIL(am)) {
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prevtick = ticks;
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am->am_waiters++;
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error = mtx_sleep(am, &am->am_lock, PCATCH,
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"acmtx", tmo);
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am->am_waiters--;
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if (error == EINTR || am->am_reset) {
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status = AE_ERROR;
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break;
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}
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if (ACPIMTX_AVAIL(am))
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break;
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slptick = ticks - prevtick;
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if (slptick >= tmo || slptick < 0) {
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status = AE_TIME;
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break;
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}
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tmo -= slptick;
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}
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}
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if (status == AE_OK)
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am->am_owner = curthread;
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mtx_unlock(&am->am_lock);
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return_ACPI_STATUS (status);
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}
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void
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AcpiOsReleaseMutex(ACPI_MUTEX Handle)
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{
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struct acpi_mutex *am = (struct acpi_mutex *)Handle;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (am == NULL) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"cannot release null mutex\n"));
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return_VOID;
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}
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mtx_lock(&am->am_lock);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "release %s\n", am->am_name));
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if (ACPIMTX_OWNED(am)) {
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if (am->am_nested > 0) {
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"release nested %s, depth %d\n",
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am->am_name, am->am_nested));
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am->am_nested--;
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} else
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am->am_owner = NULL;
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} else {
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if (ACPIMTX_AVAIL(am))
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"release already available %s\n", am->am_name));
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else
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
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"release unowned %s from %p, depth %d\n",
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am->am_name, am->am_owner, am->am_nested));
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}
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if (am->am_waiters > 0 && ACPIMTX_AVAIL(am))
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wakeup_one(am);
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mtx_unlock(&am->am_lock);
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}
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#undef ACPIMTX_AVAIL
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#undef ACPIMTX_OWNED
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/*
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* ACPI_SPINLOCK
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*/
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struct acpi_spinlock {
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struct mtx al_lock;
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char al_name[32];
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int al_nested;
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};
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ACPI_STATUS
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AcpiOsCreateLock(ACPI_SPINLOCK *OutHandle)
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{
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struct acpi_spinlock *al;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (OutHandle == NULL)
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return_ACPI_STATUS (AE_BAD_PARAMETER);
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if ((al = malloc(sizeof(*al), M_ACPISEM, M_NOWAIT | M_ZERO)) == NULL)
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return_ACPI_STATUS (AE_NO_MEMORY);
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#ifdef ACPI_DEBUG
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if (OutHandle == &AcpiGbl_GpeLock)
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snprintf(al->al_name, sizeof(al->al_name), "ACPI lock (GPE)");
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else if (OutHandle == &AcpiGbl_HardwareLock)
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snprintf(al->al_name, sizeof(al->al_name), "ACPI lock (HW)");
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else
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#endif
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snprintf(al->al_name, sizeof(al->al_name), "ACPI lock (%p)", al);
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mtx_init(&al->al_lock, al->al_name, NULL, MTX_SPIN);
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ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "created %s\n", al->al_name));
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*OutHandle = (ACPI_SPINLOCK)al;
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return_ACPI_STATUS (AE_OK);
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}
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void
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AcpiOsDeleteLock(ACPI_SPINLOCK Handle)
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{
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struct acpi_spinlock *al = (struct acpi_spinlock *)Handle;
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ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
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if (al == NULL) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"cannot delete null spinlock\n"));
|
|
return_VOID;
|
|
}
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "delete %s\n", al->al_name));
|
|
|
|
mtx_destroy(&al->al_lock);
|
|
free(al, M_ACPISEM);
|
|
}
|
|
|
|
ACPI_CPU_FLAGS
|
|
AcpiOsAcquireLock(ACPI_SPINLOCK Handle)
|
|
{
|
|
struct acpi_spinlock *al = (struct acpi_spinlock *)Handle;
|
|
|
|
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
|
|
|
|
if (al == NULL) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"cannot acquire null spinlock\n"));
|
|
return (0);
|
|
}
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "acquire %s\n", al->al_name));
|
|
|
|
if (mtx_owned(&al->al_lock)) {
|
|
al->al_nested++;
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"acquire nested %s, depth %d\n",
|
|
al->al_name, al->al_nested));
|
|
} else
|
|
mtx_lock_spin(&al->al_lock);
|
|
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
AcpiOsReleaseLock(ACPI_SPINLOCK Handle, ACPI_CPU_FLAGS Flags)
|
|
{
|
|
struct acpi_spinlock *al = (struct acpi_spinlock *)Handle;
|
|
|
|
ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
|
|
|
|
if (al == NULL) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"cannot release null spinlock\n"));
|
|
return_VOID;
|
|
}
|
|
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "release %s\n", al->al_name));
|
|
|
|
if (mtx_owned(&al->al_lock)) {
|
|
if (al->al_nested > 0) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"release nested %s, depth %d\n",
|
|
al->al_name, al->al_nested));
|
|
al->al_nested--;
|
|
} else
|
|
mtx_unlock_spin(&al->al_lock);
|
|
} else
|
|
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
|
|
"cannot release unowned %s\n", al->al_name));
|
|
}
|
|
|
|
/* Section 5.2.10.1: global lock acquire/release functions */
|
|
#define GL_ACQUIRED (-1)
|
|
#define GL_BUSY 0
|
|
#define GL_BIT_PENDING 0x01
|
|
#define GL_BIT_OWNED 0x02
|
|
#define GL_BIT_MASK (GL_BIT_PENDING | GL_BIT_OWNED)
|
|
|
|
/*
|
|
* Acquire the global lock. If busy, set the pending bit. The caller
|
|
* will wait for notification from the BIOS that the lock is available
|
|
* and then attempt to acquire it again.
|
|
*/
|
|
int
|
|
acpi_acquire_global_lock(uint32_t *lock)
|
|
{
|
|
uint32_t new, old;
|
|
|
|
do {
|
|
old = *lock;
|
|
new = ((old & ~GL_BIT_MASK) | GL_BIT_OWNED) |
|
|
((old >> 1) & GL_BIT_PENDING);
|
|
} while (atomic_cmpset_acq_int(lock, old, new) == 0);
|
|
|
|
return ((new < GL_BIT_MASK) ? GL_ACQUIRED : GL_BUSY);
|
|
}
|
|
|
|
/*
|
|
* Release the global lock, returning whether there is a waiter pending.
|
|
* If the BIOS set the pending bit, OSPM must notify the BIOS when it
|
|
* releases the lock.
|
|
*/
|
|
int
|
|
acpi_release_global_lock(uint32_t *lock)
|
|
{
|
|
uint32_t new, old;
|
|
|
|
do {
|
|
old = *lock;
|
|
new = old & ~GL_BIT_MASK;
|
|
} while (atomic_cmpset_rel_int(lock, old, new) == 0);
|
|
|
|
return (old & GL_BIT_PENDING);
|
|
}
|