/*******************************************************************************

 *

 * Module Name: utmutex - local mutex support

 *

 ******************************************************************************/

/*

 * Copyright (C) 2000 - 2018, Intel Corp.

 * 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,

 *    without modification.

 * 2. Redistributions in binary form must reproduce at minimum a disclaimer

 *    substantially similar to the "NO WARRANTY" disclaimer below

 *    ("Disclaimer") and any redistribution must be conditioned upon

 *    including a substantially similar Disclaimer requirement for further

 *    binary redistribution.

 * 3. Neither the names of the above-listed copyright holders nor the names

 *    of any contributors may be used to endorse or promote products derived

 *    from this software without specific prior written permission.

 *

 * Alternatively, this software may be distributed under the terms of the

 * GNU General Public License ("GPL") version 2 as published by the Free

 * Software Foundation.

 *

 * NO WARRANTY

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.

 */

#include "acpi.h"

#include "accommon.h"

#define _COMPONENT          ACPI_UTILITIES

        ACPI_MODULE_NAME    ("utmutex")

/* Local prototypes */

static ACPI_STATUS

AcpiUtCreateMutex (

    ACPI_MUTEX_HANDLE       MutexId);

static void

AcpiUtDeleteMutex (

    ACPI_MUTEX_HANDLE       MutexId);

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtMutexInitialize

 *

 * PARAMETERS:  None.

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Create the system mutex objects. This includes mutexes,

 *              spin locks, and reader/writer locks.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiUtMutexInitialize (

    void)

{

    UINT32                  i;

    ACPI_STATUS             Status;

    ACPI_FUNCTION_TRACE (UtMutexInitialize);

    /* Create each of the predefined mutex objects */

    for (i = 0; i < ACPI_NUM_MUTEX; i++)

    {

        Status = AcpiUtCreateMutex (i);

        if (ACPI_FAILURE (Status))

        {

            return_ACPI_STATUS (Status);

        }

    }

    /* Create the spinlocks for use at interrupt level or for speed */

    Status = AcpiOsCreateLock (&AcpiGbl_GpeLock);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    Status = AcpiOsCreateLock (&AcpiGbl_HardwareLock);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    Status = AcpiOsCreateLock (&AcpiGbl_ReferenceCountLock);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    /* Mutex for _OSI support */

    Status = AcpiOsCreateMutex (&AcpiGbl_OsiMutex);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    /* Create the reader/writer lock for namespace access */

    Status = AcpiUtCreateRwLock (&AcpiGbl_NamespaceRwLock);

    if (ACPI_FAILURE (Status))

    {

        return_ACPI_STATUS (Status);

    }

    return_ACPI_STATUS (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtMutexTerminate

 *

 * PARAMETERS:  None.

 *

 * RETURN:      None.

 *

 * DESCRIPTION: Delete all of the system mutex objects. This includes mutexes,

 *              spin locks, and reader/writer locks.

 *

 ******************************************************************************/

void

AcpiUtMutexTerminate (

    void)

{

    UINT32                  i;

    ACPI_FUNCTION_TRACE (UtMutexTerminate);

    /* Delete each predefined mutex object */

    for (i = 0; i < ACPI_NUM_MUTEX; i++)

    {

        AcpiUtDeleteMutex (i);

    }

    AcpiOsDeleteMutex (AcpiGbl_OsiMutex);

    /* Delete the spinlocks */

    AcpiOsDeleteLock (AcpiGbl_GpeLock);

    AcpiOsDeleteLock (AcpiGbl_HardwareLock);

    AcpiOsDeleteLock (AcpiGbl_ReferenceCountLock);

    /* Delete the reader/writer lock */

    AcpiUtDeleteRwLock (&AcpiGbl_NamespaceRwLock);

    return_VOID;

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtCreateMutex

 *

 * PARAMETERS:  MutexID         - ID of the mutex to be created

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Create a mutex object.

 *

 ******************************************************************************/

static ACPI_STATUS

AcpiUtCreateMutex (

    ACPI_MUTEX_HANDLE       MutexId)

{

    ACPI_STATUS             Status = AE_OK;

    ACPI_FUNCTION_TRACE_U32 (UtCreateMutex, MutexId);

    if (!AcpiGbl_MutexInfo[MutexId].Mutex)

    {

        Status = AcpiOsCreateMutex (&AcpiGbl_MutexInfo[MutexId].Mutex);

        AcpiGbl_MutexInfo[MutexId].ThreadId = ACPI_MUTEX_NOT_ACQUIRED;

        AcpiGbl_MutexInfo[MutexId].UseCount = 0;

    }

    return_ACPI_STATUS (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtDeleteMutex

 *

 * PARAMETERS:  MutexID         - ID of the mutex to be deleted

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Delete a mutex object.

 *

 ******************************************************************************/

static void

AcpiUtDeleteMutex (

    ACPI_MUTEX_HANDLE       MutexId)

{

    ACPI_FUNCTION_TRACE_U32 (UtDeleteMutex, MutexId);

    AcpiOsDeleteMutex (AcpiGbl_MutexInfo[MutexId].Mutex);

    AcpiGbl_MutexInfo[MutexId].Mutex = NULL;

    AcpiGbl_MutexInfo[MutexId].ThreadId = ACPI_MUTEX_NOT_ACQUIRED;

    return_VOID;

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtAcquireMutex

 *

 * PARAMETERS:  MutexID         - ID of the mutex to be acquired

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Acquire a mutex object.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiUtAcquireMutex (

    ACPI_MUTEX_HANDLE       MutexId)

{

    ACPI_STATUS             Status;

    ACPI_THREAD_ID          ThisThreadId;

    ACPI_FUNCTION_NAME (UtAcquireMutex);

    if (MutexId > ACPI_MAX_MUTEX)

    {

        return (AE_BAD_PARAMETER);

    }

    ThisThreadId = AcpiOsGetThreadId ();

#ifdef ACPI_MUTEX_DEBUG

    {

        UINT32                  i;

        /*

         * Mutex debug code, for internal debugging only.

         *

         * Deadlock prevention. Check if this thread owns any mutexes of value

         * greater than or equal to this one. If so, the thread has violated

         * the mutex ordering rule. This indicates a coding error somewhere in

         * the ACPI subsystem code.

         */

        for (i = MutexId; i < ACPI_NUM_MUTEX; i++)

        {

            if (AcpiGbl_MutexInfo[i].ThreadId == ThisThreadId)

            {

                if (i == MutexId)

                {

                    ACPI_ERROR ((AE_INFO,

                        "Mutex [%s] already acquired by this thread [%u]",

                        AcpiUtGetMutexName (MutexId),

                        (UINT32) ThisThreadId));

                    return (AE_ALREADY_ACQUIRED);

                }

                ACPI_ERROR ((AE_INFO,

                    "Invalid acquire order: Thread %u owns [%s], wants [%s]",

                    (UINT32) ThisThreadId, AcpiUtGetMutexName (i),

                    AcpiUtGetMutexName (MutexId)));

                return (AE_ACQUIRE_DEADLOCK);

            }

        }

    }

#endif

    ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,

        "Thread %u attempting to acquire Mutex [%s]\n",

        (UINT32) ThisThreadId, AcpiUtGetMutexName (MutexId)));

    Status = AcpiOsAcquireMutex (

        AcpiGbl_MutexInfo[MutexId].Mutex, ACPI_WAIT_FOREVER);

    if (ACPI_SUCCESS (Status))

    {

        ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,

            "Thread %u acquired Mutex [%s]\n",

            (UINT32) ThisThreadId, AcpiUtGetMutexName (MutexId)));

        AcpiGbl_MutexInfo[MutexId].UseCount++;

        AcpiGbl_MutexInfo[MutexId].ThreadId = ThisThreadId;

    }

    else

    {

        ACPI_EXCEPTION ((AE_INFO, Status,

            "Thread %u could not acquire Mutex [%s] (0x%X)",

            (UINT32) ThisThreadId, AcpiUtGetMutexName (MutexId), MutexId));

    }

    return (Status);

}

/*******************************************************************************

 *

 * FUNCTION:    AcpiUtReleaseMutex

 *

 * PARAMETERS:  MutexID         - ID of the mutex to be released

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Release a mutex object.

 *

 ******************************************************************************/

ACPI_STATUS

AcpiUtReleaseMutex (

    ACPI_MUTEX_HANDLE       MutexId)

{

    ACPI_FUNCTION_NAME (UtReleaseMutex);

    ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",

        (UINT32) AcpiOsGetThreadId (), AcpiUtGetMutexName (MutexId)));

    if (MutexId > ACPI_MAX_MUTEX)

    {

        return (AE_BAD_PARAMETER);

    }

    /*

     * Mutex must be acquired in order to release it!

     */

    if (AcpiGbl_MutexInfo[MutexId].ThreadId == ACPI_MUTEX_NOT_ACQUIRED)

    {

        ACPI_ERROR ((AE_INFO,

            "Mutex [%s] (0x%X) is not acquired, cannot release",

            AcpiUtGetMutexName (MutexId), MutexId));

        return (AE_NOT_ACQUIRED);

    }

#ifdef ACPI_MUTEX_DEBUG

    {

        UINT32                  i;

        /*

         * Mutex debug code, for internal debugging only.

         *

         * Deadlock prevention. Check if this thread owns any mutexes of value

         * greater than this one. If so, the thread has violated the mutex

         * ordering rule. This indicates a coding error somewhere in

         * the ACPI subsystem code.

         */

        for (i = MutexId; i < ACPI_NUM_MUTEX; i++)

        {

            if (AcpiGbl_MutexInfo[i].ThreadId == AcpiOsGetThreadId ())

            {

                if (i == MutexId)

                {

                    continue;

                }

                ACPI_ERROR ((AE_INFO,

                    "Invalid release order: owns [%s], releasing [%s]",

                    AcpiUtGetMutexName (i), AcpiUtGetMutexName (MutexId)));

                return (AE_RELEASE_DEADLOCK);

            }

        }

    }

#endif

    /* Mark unlocked FIRST */

    AcpiGbl_MutexInfo[MutexId].ThreadId = ACPI_MUTEX_NOT_ACQUIRED;

    AcpiOsReleaseMutex (AcpiGbl_MutexInfo[MutexId].Mutex);

    return (AE_OK);

}