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 /******************************************************************************
  *
  * Module Name: exmutex - ASL Mutex Acquire/Release functions
  *
  *****************************************************************************/
 
 /******************************************************************************
  *
  * 1. Copyright Notice
  *
  * Some or all of this work - Copyright (c) 1999 - 2009, Intel Corp.
  * All rights reserved.
  *
  * 2. License
  *
  * 2.1. This is your license from Intel Corp. under its intellectual property
  * rights.  You may have additional license terms from the party that provided
  * you this software, covering your right to use that party's intellectual
  * property rights.
  *
  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  * copy of the source code appearing in this file ("Covered Code") an
  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  * base code distributed originally by Intel ("Original Intel Code") to copy,
  * make derivatives, distribute, use and display any portion of the Covered
  * Code in any form, with the right to sublicense such rights; and
  *
  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  * license (with the right to sublicense), under only those claims of Intel
  * patents that are infringed by the Original Intel Code, to make, use, sell,
  * offer to sell, and import the Covered Code and derivative works thereof
  * solely to the minimum extent necessary to exercise the above copyright
  * license, and in no event shall the patent license extend to any additions
  * to or modifications of the Original Intel Code.  No other license or right
  * is granted directly or by implication, estoppel or otherwise;
  *
  * The above copyright and patent license is granted only if the following
  * conditions are met:
  *
  * 3. Conditions
  *
  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification with rights to further distribute source must include
  * the above Copyright Notice, the above License, this list of Conditions,
  * and the following Disclaimer and Export Compliance provision.  In addition,
  * Licensee must cause all Covered Code to which Licensee contributes to
  * contain a file documenting the changes Licensee made to create that Covered
  * Code and the date of any change.  Licensee must include in that file the
  * documentation of any changes made by any predecessor Licensee.  Licensee
  * must include a prominent statement that the modification is derived,
  * directly or indirectly, from Original Intel Code.
  *
  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification without rights to further distribute source must
  * include the following Disclaimer and Export Compliance provision in the
  * documentation and/or other materials provided with distribution.  In
  * addition, Licensee may not authorize further sublicense of source of any
  * portion of the Covered Code, and must include terms to the effect that the
  * license from Licensee to its licensee is limited to the intellectual
  * property embodied in the software Licensee provides to its licensee, and
  * not to intellectual property embodied in modifications its licensee may
  * make.
  *
  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  * substantial portion of the Covered Code or modification must reproduce the
  * above Copyright Notice, and the following Disclaimer and Export Compliance
  * provision in the documentation and/or other materials provided with the
  * distribution.
  *
  * 3.4. Intel retains all right, title, and interest in and to the Original
  * Intel Code.
  *
  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  * Intel shall be used in advertising or otherwise to promote the sale, use or
  * other dealings in products derived from or relating to the Covered Code
  * without prior written authorization from Intel.
  *
  * 4. Disclaimer and Export Compliance
  *
  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  * PARTICULAR PURPOSE.
  *
  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  * LIMITED REMEDY.
  *
  * 4.3. Licensee shall not export, either directly or indirectly, any of this
  * software or system incorporating such software without first obtaining any
  * required license or other approval from the U. S. Department of Commerce or
  * any other agency or department of the United States Government.  In the
  * event Licensee exports any such software from the United States or
  * re-exports any such software from a foreign destination, Licensee shall
  * ensure that the distribution and export/re-export of the software is in
  * compliance with all laws, regulations, orders, or other restrictions of the
  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
  * any of its subsidiaries will export/re-export any technical data, process,
  * software, or service, directly or indirectly, to any country for which the
  * United States government or any agency thereof requires an export license,
  * other governmental approval, or letter of assurance, without first obtaining
  * such license, approval or letter.
  *
  *****************************************************************************/
 
 #define __EXMUTEX_C__
 
 #include "acpi.h"
 #include "accommon.h"
 #include "acinterp.h"
 #include "acevents.h"
 
 #define _COMPONENT          ACPI_EXECUTER
         ACPI_MODULE_NAME    ("exmutex")
 
 /* Local prototypes */
 
 static void
 AcpiExLinkMutex (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_THREAD_STATE       *Thread);
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExUnlinkMutex
  *
  * PARAMETERS:  ObjDesc             - The mutex to be unlinked
  *
  * RETURN:      None
  *
  * DESCRIPTION: Remove a mutex from the "AcquiredMutex" list
  *
  ******************************************************************************/
 
 void
 AcpiExUnlinkMutex (
     ACPI_OPERAND_OBJECT     *ObjDesc)
 {
     ACPI_THREAD_STATE       *Thread = ObjDesc->Mutex.OwnerThread;
 
 
     if (!Thread)
     {
         return;
     }
 
     /* Doubly linked list */
 
     if (ObjDesc->Mutex.Next)
     {
         (ObjDesc->Mutex.Next)->Mutex.Prev = ObjDesc->Mutex.Prev;
     }
 
     if (ObjDesc->Mutex.Prev)
     {
         (ObjDesc->Mutex.Prev)->Mutex.Next = ObjDesc->Mutex.Next;
 
         /*
          * Migrate the previous sync level associated with this mutex to the
          * previous mutex on the list so that it may be preserved. This handles
          * the case where several mutexes have been acquired at the same level,
          * but are not released in opposite order.
          */
         (ObjDesc->Mutex.Prev)->Mutex.OriginalSyncLevel =
             ObjDesc->Mutex.OriginalSyncLevel;
     }
     else
     {
         Thread->AcquiredMutexList = ObjDesc->Mutex.Next;
     }
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExLinkMutex
  *
  * PARAMETERS:  ObjDesc         - The mutex to be linked
  *              Thread          - Current executing thread object
  *
  * RETURN:      None
  *
  * DESCRIPTION: Add a mutex to the "AcquiredMutex" list for this walk
  *
  ******************************************************************************/
 
 static void
 AcpiExLinkMutex (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_THREAD_STATE       *Thread)
 {
     ACPI_OPERAND_OBJECT     *ListHead;
 
 
     ListHead = Thread->AcquiredMutexList;
 
     /* This object will be the first object in the list */
 
     ObjDesc->Mutex.Prev = NULL;
     ObjDesc->Mutex.Next = ListHead;
 
     /* Update old first object to point back to this object */
 
     if (ListHead)
     {
         ListHead->Mutex.Prev = ObjDesc;
     }
 
     /* Update list head */
 
     Thread->AcquiredMutexList = ObjDesc;
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExAcquireMutexObject
  *
  * PARAMETERS:  TimeDesc            - Timeout in milliseconds
  *              ObjDesc             - Mutex object
  *              Thread              - Current thread state
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Acquire an AML mutex, low-level interface. Provides a common
  *              path that supports multiple acquires by the same thread.
  *
  * MUTEX:       Interpreter must be locked
  *
  * NOTE: This interface is called from three places:
  * 1) From AcpiExAcquireMutex, via an AML Acquire() operator
  * 2) From AcpiExAcquireGlobalLock when an AML Field access requires the
  *    global lock
  * 3) From the external interface, AcpiAcquireGlobalLock
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExAcquireMutexObject (
     UINT16                  Timeout,
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_THREAD_ID          ThreadId)
 {
     ACPI_STATUS             Status;
 
 
     ACPI_FUNCTION_TRACE_PTR (ExAcquireMutexObject, ObjDesc);
 
 
     if (!ObjDesc)
     {
         return_ACPI_STATUS (AE_BAD_PARAMETER);
     }
 
     /* Support for multiple acquires by the owning thread */
 
     if (ObjDesc->Mutex.ThreadId == ThreadId)
     {
         /*
          * The mutex is already owned by this thread, just increment the
          * acquisition depth
          */
         ObjDesc->Mutex.AcquisitionDepth++;
         return_ACPI_STATUS (AE_OK);
     }
 
     /* Acquire the mutex, wait if necessary. Special case for Global Lock */
 
     if (ObjDesc == AcpiGbl_GlobalLockMutex)
     {
         Status = AcpiEvAcquireGlobalLock (Timeout);
     }
     else
     {
         Status = AcpiExSystemWaitMutex (ObjDesc->Mutex.OsMutex,
                     Timeout);
     }
 
     if (ACPI_FAILURE (Status))
     {
         /* Includes failure from a timeout on TimeDesc */
 
         return_ACPI_STATUS (Status);
     }
 
     /* Acquired the mutex: update mutex object */
 
     ObjDesc->Mutex.ThreadId = ThreadId;
     ObjDesc->Mutex.AcquisitionDepth = 1;
     ObjDesc->Mutex.OriginalSyncLevel = 0;
     ObjDesc->Mutex.OwnerThread = NULL;      /* Used only for AML Acquire() */
 
     return_ACPI_STATUS (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExAcquireMutex
  *
  * PARAMETERS:  TimeDesc            - Timeout integer
  *              ObjDesc             - Mutex object
  *              WalkState           - Current method execution state
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Acquire an AML mutex
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExAcquireMutex (
     ACPI_OPERAND_OBJECT     *TimeDesc,
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_WALK_STATE         *WalkState)
 {
     ACPI_STATUS             Status;
 
 
     ACPI_FUNCTION_TRACE_PTR (ExAcquireMutex, ObjDesc);
 
 
     if (!ObjDesc)
     {
         return_ACPI_STATUS (AE_BAD_PARAMETER);
     }
 
     /* Must have a valid thread ID */
 
     if (!WalkState->Thread)
     {
         ACPI_ERROR ((AE_INFO, "Cannot acquire Mutex [%4.4s], null thread info",
             AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
         return_ACPI_STATUS (AE_AML_INTERNAL);
     }
 
     /*
      * Current sync level must be less than or equal to the sync level of the
      * mutex. This mechanism provides some deadlock prevention
      */
     if (WalkState->Thread->CurrentSyncLevel > ObjDesc->Mutex.SyncLevel)
     {
         ACPI_ERROR ((AE_INFO,
             "Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%d)",
             AcpiUtGetNodeName (ObjDesc->Mutex.Node),
             WalkState->Thread->CurrentSyncLevel));
         return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
     }
 
     Status = AcpiExAcquireMutexObject ((UINT16) TimeDesc->Integer.Value,
                 ObjDesc, WalkState->Thread->ThreadId);
     if (ACPI_SUCCESS (Status) && ObjDesc->Mutex.AcquisitionDepth == 1)
     {
         /* Save Thread object, original/current sync levels */
 
         ObjDesc->Mutex.OwnerThread = WalkState->Thread;
         ObjDesc->Mutex.OriginalSyncLevel = WalkState->Thread->CurrentSyncLevel;
         WalkState->Thread->CurrentSyncLevel = ObjDesc->Mutex.SyncLevel;
 
         /* Link the mutex to the current thread for force-unlock at method exit */
 
         AcpiExLinkMutex (ObjDesc, WalkState->Thread);
     }
 
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExReleaseMutexObject
  *
  * PARAMETERS:  ObjDesc             - The object descriptor for this op
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Release a previously acquired Mutex, low level interface.
  *              Provides a common path that supports multiple releases (after
  *              previous multiple acquires) by the same thread.
  *
  * MUTEX:       Interpreter must be locked
  *
  * NOTE: This interface is called from three places:
  * 1) From AcpiExReleaseMutex, via an AML Acquire() operator
  * 2) From AcpiExReleaseGlobalLock when an AML Field access requires the
  *    global lock
  * 3) From the external interface, AcpiReleaseGlobalLock
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExReleaseMutexObject (
     ACPI_OPERAND_OBJECT     *ObjDesc)
 {
     ACPI_STATUS             Status = AE_OK;
 
 
     ACPI_FUNCTION_TRACE (ExReleaseMutexObject);
 
 
     if (ObjDesc->Mutex.AcquisitionDepth == 0)
     {
         return (AE_NOT_ACQUIRED);
     }
 
     /* Match multiple Acquires with multiple Releases */
 
     ObjDesc->Mutex.AcquisitionDepth--;
     if (ObjDesc->Mutex.AcquisitionDepth != 0)
     {
         /* Just decrement the depth and return */
 
         return_ACPI_STATUS (AE_OK);
     }
 
     if (ObjDesc->Mutex.OwnerThread)
     {
         /* Unlink the mutex from the owner's list */
 
         AcpiExUnlinkMutex (ObjDesc);
         ObjDesc->Mutex.OwnerThread = NULL;
     }
 
     /* Release the mutex, special case for Global Lock */
 
     if (ObjDesc == AcpiGbl_GlobalLockMutex)
     {
         Status = AcpiEvReleaseGlobalLock ();
     }
     else
     {
         AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
     }
 
     /* Clear mutex info */
 
     ObjDesc->Mutex.ThreadId = 0;
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExReleaseMutex
  *
  * PARAMETERS:  ObjDesc             - The object descriptor for this op
  *              WalkState           - Current method execution state
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Release a previously acquired Mutex.
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiExReleaseMutex (
     ACPI_OPERAND_OBJECT     *ObjDesc,
     ACPI_WALK_STATE         *WalkState)
 {
     ACPI_STATUS             Status = AE_OK;
     UINT8                   PreviousSyncLevel;
 
 
     ACPI_FUNCTION_TRACE (ExReleaseMutex);
 
 
     if (!ObjDesc)
     {
         return_ACPI_STATUS (AE_BAD_PARAMETER);
     }
 
     /* The mutex must have been previously acquired in order to release it */
 
     if (!ObjDesc->Mutex.OwnerThread)
     {
         ACPI_ERROR ((AE_INFO, "Cannot release Mutex [%4.4s], not acquired",
             AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
         return_ACPI_STATUS (AE_AML_MUTEX_NOT_ACQUIRED);
     }
 
     /*
      * The Mutex is owned, but this thread must be the owner.
      * Special case for Global Lock, any thread can release
      */
     if ((ObjDesc->Mutex.OwnerThread->ThreadId != WalkState->Thread->ThreadId) &&
         (ObjDesc != AcpiGbl_GlobalLockMutex))
     {
         ACPI_ERROR ((AE_INFO,
             "Thread %p cannot release Mutex [%4.4s] acquired by thread %p",
             ACPI_CAST_PTR (void, WalkState->Thread->ThreadId),
             AcpiUtGetNodeName (ObjDesc->Mutex.Node),
             ACPI_CAST_PTR (void, ObjDesc->Mutex.OwnerThread->ThreadId)));
         return_ACPI_STATUS (AE_AML_NOT_OWNER);
     }
 
     /* Must have a valid thread ID */
 
     if (!WalkState->Thread)
     {
         ACPI_ERROR ((AE_INFO, "Cannot release Mutex [%4.4s], null thread info",
             AcpiUtGetNodeName (ObjDesc->Mutex.Node)));
         return_ACPI_STATUS (AE_AML_INTERNAL);
     }
 
     /*
      * The sync level of the mutex must be equal to the current sync level. In
      * other words, the current level means that at least one mutex at that
      * level is currently being held. Attempting to release a mutex of a
      * different level can only mean that the mutex ordering rule is being
      * violated. This behavior is clarified in ACPI 4.0 specification.
      */
     if (ObjDesc->Mutex.SyncLevel != WalkState->Thread->CurrentSyncLevel)
     {
         ACPI_ERROR ((AE_INFO,
             "Cannot release Mutex [%4.4s], SyncLevel mismatch: mutex %d current %d",
             AcpiUtGetNodeName (ObjDesc->Mutex.Node),
             ObjDesc->Mutex.SyncLevel, WalkState->Thread->CurrentSyncLevel));
         return_ACPI_STATUS (AE_AML_MUTEX_ORDER);
     }
 
     /*
      * Get the previous SyncLevel from the head of the acquired mutex list.
      * This handles the case where several mutexes at the same level have been
      * acquired, but are not released in reverse order.
      */
     PreviousSyncLevel =
         WalkState->Thread->AcquiredMutexList->Mutex.OriginalSyncLevel;
 
     Status = AcpiExReleaseMutexObject (ObjDesc);
     if (ACPI_FAILURE (Status))
     {
         return_ACPI_STATUS (Status);
     }
 
     if (ObjDesc->Mutex.AcquisitionDepth == 0)
     {
         /* Restore the previous SyncLevel */
 
         WalkState->Thread->CurrentSyncLevel = PreviousSyncLevel;
     }
     return_ACPI_STATUS (Status);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiExReleaseAllMutexes
  *
  * PARAMETERS:  Thread          - Current executing thread object
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Release all mutexes held by this thread
  *
  * NOTE: This function is called as the thread is exiting the interpreter.
  * Mutexes are not released when an individual control method is exited, but
  * only when the parent thread actually exits the interpreter. This allows one
  * method to acquire a mutex, and a different method to release it, as long as
  * this is performed underneath a single parent control method.
  *
  ******************************************************************************/
 
 void
 AcpiExReleaseAllMutexes (
     ACPI_THREAD_STATE       *Thread)
 {
     ACPI_OPERAND_OBJECT     *Next = Thread->AcquiredMutexList;
     ACPI_OPERAND_OBJECT     *ObjDesc;
 
 
     ACPI_FUNCTION_ENTRY ();
 
 
     /* Traverse the list of owned mutexes, releasing each one */
 
     while (Next)
     {
         ObjDesc = Next;
         Next = ObjDesc->Mutex.Next;
 
         ObjDesc->Mutex.Prev = NULL;
         ObjDesc->Mutex.Next = NULL;
         ObjDesc->Mutex.AcquisitionDepth = 0;
 
         /* Release the mutex, special case for Global Lock */
 
         if (ObjDesc == AcpiGbl_GlobalLockMutex)
         {
             /* Ignore errors */
 
             (void) AcpiEvReleaseGlobalLock ();
         }
         else
         {
             AcpiOsReleaseMutex (ObjDesc->Mutex.OsMutex);
         }
 
         /* Mark mutex unowned */
 
         ObjDesc->Mutex.OwnerThread = NULL;
         ObjDesc->Mutex.ThreadId = 0;
 
         /* Update Thread SyncLevel (Last mutex is the important one) */
 
         Thread->CurrentSyncLevel = ObjDesc->Mutex.OriginalSyncLevel;
     }
 }