nsxfeval.c File Reference

#include "acpi.h"
#include "accommon.h"
#include "acnamesp.h"
#include "acinterp.h"

Include dependency graph for nsxfeval.c:

Go to the source code of this file.

Macros
#define	EXPORT_ACPI_INTERFACES
#define	_COMPONENT   ACPI_NAMESPACE

Functions
static void	AcpiNsResolveReferences (ACPI_EVALUATE_INFO *Info)
ACPI_STATUS	AcpiEvaluateObjectTyped (ACPI_HANDLE Handle, ACPI_STRING Pathname, ACPI_OBJECT_LIST *ExternalParams, ACPI_BUFFER *ReturnBuffer, ACPI_OBJECT_TYPE ReturnType)
ACPI_STATUS	AcpiEvaluateObject (ACPI_HANDLE Handle, ACPI_STRING Pathname, ACPI_OBJECT_LIST *ExternalParams, ACPI_BUFFER *ReturnBuffer)
ACPI_STATUS	AcpiWalkNamespace (ACPI_OBJECT_TYPE Type, ACPI_HANDLE StartObject, UINT32 MaxDepth, ACPI_WALK_CALLBACK DescendingCallback, ACPI_WALK_CALLBACK AscendingCallback, void *Context, void **ReturnValue)
static ACPI_STATUS	AcpiNsGetDeviceCallback (ACPI_HANDLE ObjHandle, UINT32 NestingLevel, void *Context, void **ReturnValue)
ACPI_STATUS	AcpiGetDevices (char *HID, ACPI_WALK_CALLBACK UserFunction, void *Context, void **ReturnValue)
ACPI_STATUS	AcpiAttachData (ACPI_HANDLE ObjHandle, ACPI_OBJECT_HANDLER Handler, void *Data)
ACPI_STATUS	AcpiDetachData (ACPI_HANDLE ObjHandle, ACPI_OBJECT_HANDLER Handler)
ACPI_STATUS	AcpiGetData (ACPI_HANDLE ObjHandle, ACPI_OBJECT_HANDLER Handler, void **Data)

Macro Definition Documentation

_COMPONENT

#define _COMPONENT   ACPI_NAMESPACE

Definition at line 53 of file nsxfeval.c.

EXPORT_ACPI_INTERFACES

#define EXPORT_ACPI_INTERFACES

Definition at line 45 of file nsxfeval.c.

Function Documentation

AcpiAttachData()

ACPI_STATUS AcpiAttachData	(	ACPI_HANDLE	ObjHandle,
		ACPI_OBJECT_HANDLER	Handler,
		void *	Data
	)

Definition at line 952 of file nsxfeval.c.

{
    ACPI_NAMESPACE_NODE     *Node;
    ACPI_STATUS             Status;
 
 
    /* Parameter validation */
 
    if (!ObjHandle  ||
        !Handler    ||
        !Data)
    {
        return (AE_BAD_PARAMETER);
    }
 
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return (Status);
    }
 
    /* Convert and validate the handle */
 
    Node = AcpiNsValidateHandle (ObjHandle);
    if (!Node)
    {
        Status = AE_BAD_PARAMETER;
        goto UnlockAndExit;
    }
 
    Status = AcpiNsAttachData (Node, Handler, Data);
 
UnlockAndExit:
    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    return (Status);
}

Referenced by acpi_bus_add().

AcpiDetachData()

ACPI_STATUS AcpiDetachData	(	ACPI_HANDLE	ObjHandle,
		ACPI_OBJECT_HANDLER	Handler
	)

Definition at line 1009 of file nsxfeval.c.

{
    ACPI_NAMESPACE_NODE     *Node;
    ACPI_STATUS             Status;
 
 
    /* Parameter validation */
 
    if (!ObjHandle  ||
        !Handler)
    {
        return (AE_BAD_PARAMETER);
    }
 
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return (Status);
    }
 
    /* Convert and validate the handle */
 
    Node = AcpiNsValidateHandle (ObjHandle);
    if (!Node)
    {
        Status = AE_BAD_PARAMETER;
        goto UnlockAndExit;
    }
 
    Status = AcpiNsDetachData (Node, Handler);
 
UnlockAndExit:
    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    return (Status);
}

AcpiEvaluateObject()

ACPI_STATUS AcpiEvaluateObject	(	ACPI_HANDLE	Handle,
		ACPI_STRING	Pathname,
		ACPI_OBJECT_LIST *	ExternalParams,
		ACPI_BUFFER *	ReturnBuffer
	)

Definition at line 217 of file nsxfeval.c.

{
    ACPI_STATUS             Status;
    ACPI_EVALUATE_INFO      *Info;
    ACPI_SIZE               BufferSpaceNeeded;
    UINT32                  i;
 
 
    ACPI_FUNCTION_TRACE (AcpiEvaluateObject);
 
 
    /* Allocate and initialize the evaluation information block */
 
    Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
    if (!Info)
    {
        return_ACPI_STATUS (AE_NO_MEMORY);
    }
 
    /* Convert and validate the device handle */
 
    Info->PrefixNode = AcpiNsValidateHandle (Handle);
    if (!Info->PrefixNode)
    {
        Status = AE_BAD_PARAMETER;
        goto Cleanup;
    }
 
    /*
     * Get the actual namespace node for the target object.
     * Handles these cases:
     *
     * 1) Null node, valid pathname from root (absolute path)
     * 2) Node and valid pathname (path relative to Node)
     * 3) Node, Null pathname
     */
    if ((Pathname) &&
        (ACPI_IS_ROOT_PREFIX (Pathname[0])))
    {
        /* The path is fully qualified, just evaluate by name */
 
        Info->PrefixNode = NULL;
    }
    else if (!Handle)
    {
        /*
         * A handle is optional iff a fully qualified pathname is specified.
         * Since we've already handled fully qualified names above, this is
         * an error.
         */
        if (!Pathname)
        {
            ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                "Both Handle and Pathname are NULL"));
        }
        else
        {
            ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                "Null Handle with relative pathname [%s]", Pathname));
        }
 
        Status = AE_BAD_PARAMETER;
        goto Cleanup;
    }
 
    Info->RelativePathname = Pathname;
 
    /*
     * Convert all external objects passed as arguments to the
     * internal version(s).
     */
    if (ExternalParams && ExternalParams->Count)
    {
        Info->ParamCount = (UINT16) ExternalParams->Count;
 
        /* Warn on impossible argument count */
 
        if (Info->ParamCount > ACPI_METHOD_NUM_ARGS)
        {
            ACPI_WARN_PREDEFINED ((AE_INFO, Pathname, ACPI_WARN_ALWAYS,
                "Excess arguments (%u) - using only %u",
                Info->ParamCount, ACPI_METHOD_NUM_ARGS));
 
            Info->ParamCount = ACPI_METHOD_NUM_ARGS;
        }
 
        /*
         * Allocate a new parameter block for the internal objects
         * Add 1 to count to allow for null terminated internal list
         */
        Info->Parameters = ACPI_ALLOCATE_ZEROED (
            ((ACPI_SIZE) Info->ParamCount + 1) * sizeof (void *));
        if (!Info->Parameters)
        {
            Status = AE_NO_MEMORY;
            goto Cleanup;
        }
 
        /* Convert each external object in the list to an internal object */
 
        for (i = 0; i < Info->ParamCount; i++)
        {
            Status = AcpiUtCopyEobjectToIobject (
                &ExternalParams->Pointer[i], &Info->Parameters[i]);
            if (ACPI_FAILURE (Status))
            {
                goto Cleanup;
            }
        }
 
        Info->Parameters[Info->ParamCount] = NULL;
    }
 
 
#ifdef _FUTURE_FEATURE
 
    /*
     * Begin incoming argument count analysis. Check for too few args
     * and too many args.
     */
    switch (AcpiNsGetType (Info->Node))
    {
    case ACPI_TYPE_METHOD:
 
        /* Check incoming argument count against the method definition */
 
        if (Info->ObjDesc->Method.ParamCount > Info->ParamCount)
        {
            ACPI_ERROR ((AE_INFO,
                "Insufficient arguments (%u) - %u are required",
                Info->ParamCount,
                Info->ObjDesc->Method.ParamCount));
 
            Status = AE_MISSING_ARGUMENTS;
            goto Cleanup;
        }
 
        else if (Info->ObjDesc->Method.ParamCount < Info->ParamCount)
        {
            ACPI_WARNING ((AE_INFO,
                "Excess arguments (%u) - only %u are required",
                Info->ParamCount,
                Info->ObjDesc->Method.ParamCount));
 
            /* Just pass the required number of arguments */
 
            Info->ParamCount = Info->ObjDesc->Method.ParamCount;
        }
 
        /*
         * Any incoming external objects to be passed as arguments to the
         * method must be converted to internal objects
         */
        if (Info->ParamCount)
        {
            /*
             * Allocate a new parameter block for the internal objects
             * Add 1 to count to allow for null terminated internal list
             */
            Info->Parameters = ACPI_ALLOCATE_ZEROED (
                ((ACPI_SIZE) Info->ParamCount + 1) * sizeof (void *));
            if (!Info->Parameters)
            {
                Status = AE_NO_MEMORY;
                goto Cleanup;
            }
 
            /* Convert each external object in the list to an internal object */
 
            for (i = 0; i < Info->ParamCount; i++)
            {
                Status = AcpiUtCopyEobjectToIobject (
                    &ExternalParams->Pointer[i], &Info->Parameters[i]);
                if (ACPI_FAILURE (Status))
                {
                    goto Cleanup;
                }
            }
 
            Info->Parameters[Info->ParamCount] = NULL;
        }
        break;
 
    default:
 
        /* Warn if arguments passed to an object that is not a method */
 
        if (Info->ParamCount)
        {
            ACPI_WARNING ((AE_INFO,
                "%u arguments were passed to a non-method ACPI object",
                Info->ParamCount));
        }
        break;
    }
 
#endif
 
 
    /* Now we can evaluate the object */
 
    Status = AcpiNsEvaluate (Info);
 
    /*
     * If we are expecting a return value, and all went well above,
     * copy the return value to an external object.
     */
    if (!ReturnBuffer)
    {
        goto CleanupReturnObject;
    }
 
    if (!Info->ReturnObject)
    {
        ReturnBuffer->Length = 0;
        goto Cleanup;
    }
 
    if (ACPI_GET_DESCRIPTOR_TYPE (Info->ReturnObject) ==
        ACPI_DESC_TYPE_NAMED)
    {
        /*
         * If we received a NS Node as a return object, this means that
         * the object we are evaluating has nothing interesting to
         * return (such as a mutex, etc.)  We return an error because
         * these types are essentially unsupported by this interface.
         * We don't check up front because this makes it easier to add
         * support for various types at a later date if necessary.
         */
        Status = AE_TYPE;
        Info->ReturnObject = NULL;   /* No need to delete a NS Node */
        ReturnBuffer->Length = 0;
    }
 
    if (ACPI_FAILURE (Status))
    {
        goto CleanupReturnObject;
    }
 
    /* Dereference Index and RefOf references */
 
    AcpiNsResolveReferences (Info);
 
    /* Get the size of the returned object */
 
    Status = AcpiUtGetObjectSize (Info->ReturnObject,
        &BufferSpaceNeeded);
    if (ACPI_SUCCESS (Status))
    {
        /* Validate/Allocate/Clear caller buffer */
 
        Status = AcpiUtInitializeBuffer (ReturnBuffer,
            BufferSpaceNeeded);
        if (ACPI_FAILURE (Status))
        {
            /*
             * Caller's buffer is too small or a new one can't
             * be allocated
             */
            ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                "Needed buffer size %X, %s\n",
                (UINT32) BufferSpaceNeeded,
                AcpiFormatException (Status)));
        }
        else
        {
            /* We have enough space for the object, build it */
 
            Status = AcpiUtCopyIobjectToEobject (
                Info->ReturnObject, ReturnBuffer);
        }
    }
 
CleanupReturnObject:
 
    if (Info->ReturnObject)
    {
        /*
         * Delete the internal return object. NOTE: Interpreter must be
         * locked to avoid race condition.
         */
        AcpiExEnterInterpreter ();
 
        /* Remove one reference on the return object (should delete it) */
 
        AcpiUtRemoveReference (Info->ReturnObject);
        AcpiExExitInterpreter ();
    }
 
 
Cleanup:
 
    /* Free the input parameter list (if we created one) */
 
    if (Info->Parameters)
    {
        /* Free the allocated parameter block */
 
        AcpiUtDeleteInternalObjectList (Info->Parameters);
    }
 
    ACPI_FREE (Info);
    return_ACPI_STATUS (Status);
}

Referenced by acpi_bus_set_power(), acpi_device_sleep_wake(), acpi_evaluate_integer(), acpi_evaluate_reference(), acpi_power_add(), acpi_power_off_device(), acpi_power_on(), AcpiEnterSleepStatePrep(), AcpiEvaluateObject(), AcpiEvaluateObjectTyped(), AcpiEvExecuteOrphanRegMethod(), AcpiHwExecuteSleepMethod(), and EvalEvaluateObject().

AcpiEvaluateObjectTyped()

ACPI_STATUS AcpiEvaluateObjectTyped	(	ACPI_HANDLE	Handle,
		ACPI_STRING	Pathname,
		ACPI_OBJECT_LIST *	ExternalParams,
		ACPI_BUFFER *	ReturnBuffer,
		ACPI_OBJECT_TYPE	ReturnType
	)

Definition at line 85 of file nsxfeval.c.

{
    ACPI_STATUS             Status;
    BOOLEAN                 FreeBufferOnError = FALSE;
    ACPI_HANDLE             TargetHandle;
    char                    *FullPathname;
 
 
    ACPI_FUNCTION_TRACE (AcpiEvaluateObjectTyped);
 
 
    /* Return buffer must be valid */
 
    if (!ReturnBuffer)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    if (ReturnBuffer->Length == ACPI_ALLOCATE_BUFFER)
    {
        FreeBufferOnError = TRUE;
    }
 
    /* Get a handle here, in order to build an error message if needed */
 
    TargetHandle = Handle;
    if (Pathname)
    {
        Status = AcpiGetHandle (Handle, Pathname, &TargetHandle);
        if (ACPI_FAILURE (Status))
        {
            return_ACPI_STATUS (Status);
        }
    }
 
    FullPathname = AcpiNsGetExternalPathname (TargetHandle);
    if (!FullPathname)
    {
        return_ACPI_STATUS (AE_NO_MEMORY);
    }
 
    /* Evaluate the object */
 
    Status = AcpiEvaluateObject (TargetHandle, NULL, ExternalParams,
        ReturnBuffer);
    if (ACPI_FAILURE (Status))
    {
        goto Exit;
    }
 
    /* Type ANY means "don't care about return value type" */
 
    if (ReturnType == ACPI_TYPE_ANY)
    {
        goto Exit;
    }
 
    if (ReturnBuffer->Length == 0)
    {
        /* Error because caller specifically asked for a return value */
 
        ACPI_ERROR ((AE_INFO, "%s did not return any object",
            FullPathname));
        Status = AE_NULL_OBJECT;
        goto Exit;
    }
 
    /* Examine the object type returned from EvaluateObject */
 
    if (((ACPI_OBJECT *) ReturnBuffer->Pointer)->Type == ReturnType)
    {
        goto Exit;
    }
 
    /* Return object type does not match requested type */
 
    ACPI_ERROR ((AE_INFO,
        "Incorrect return type from %s - received [%s], requested [%s]",
        FullPathname,
        AcpiUtGetTypeName (((ACPI_OBJECT *) ReturnBuffer->Pointer)->Type),
        AcpiUtGetTypeName (ReturnType)));
 
    if (FreeBufferOnError)
    {
        /*
         * Free a buffer created via ACPI_ALLOCATE_BUFFER.
         * Note: We use AcpiOsFree here because AcpiOsAllocate was used
         * to allocate the buffer. This purposefully bypasses the
         * (optionally enabled) allocation tracking mechanism since we
         * only want to track internal allocations.
         */
        AcpiOsFree (ReturnBuffer->Pointer);
        ReturnBuffer->Pointer = NULL;
    }
 
    ReturnBuffer->Length = 0;
    Status = AE_TYPE;
 
Exit:
    ACPI_FREE (FullPathname);
    return_ACPI_STATUS (Status);
}

Referenced by AcpiEvaluateObjectTyped().

AcpiGetData()

ACPI_STATUS AcpiGetData	(	ACPI_HANDLE	ObjHandle,
		ACPI_OBJECT_HANDLER	Handler,
		void **	Data
	)

Definition at line 1065 of file nsxfeval.c.

{
    ACPI_NAMESPACE_NODE     *Node;
    ACPI_STATUS             Status;
 
 
    /* Parameter validation */
 
    if (!ObjHandle  ||
        !Handler    ||
        !Data)
    {
        return (AE_BAD_PARAMETER);
    }
 
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return (Status);
    }
 
    /* Convert and validate the handle */
 
    Node = AcpiNsValidateHandle (ObjHandle);
    if (!Node)
    {
        Status = AE_BAD_PARAMETER;
        goto UnlockAndExit;
    }
 
    Status = AcpiNsGetAttachedData (Node, Handler, Data);
 
UnlockAndExit:
    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    return (Status);
}

Referenced by acpi_bus_get_device(), and acpi_bus_get_private_data().

AcpiGetDevices()

ACPI_STATUS AcpiGetDevices	(	char *	HID,
		ACPI_WALK_CALLBACK	UserFunction,
		void *	Context,
		void **	ReturnValue
	)

Definition at line 886 of file nsxfeval.c.

{
    ACPI_STATUS             Status;
    ACPI_GET_DEVICES_INFO   Info;
 
 
    ACPI_FUNCTION_TRACE (AcpiGetDevices);
 
 
    /* Parameter validation */
 
    if (!UserFunction)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    /*
     * We're going to call their callback from OUR callback, so we need
     * to know what it is, and their context parameter.
     */
    Info.Hid = HID;
    Info.Context = Context;
    Info.UserFunction = UserFunction;
 
    /*
     * Lock the namespace around the walk.
     * The namespace will be unlocked/locked around each call
     * to the user function - since this function
     * must be allowed to make Acpi calls itself.
     */
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return_ACPI_STATUS (Status);
    }
 
    Status = AcpiNsWalkNamespace (ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
        ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
        AcpiNsGetDeviceCallback, NULL, &Info, ReturnValue);
 
    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    return_ACPI_STATUS (Status);
}

Referenced by AcpiGetDevices().

AcpiNsGetDeviceCallback()

static ACPI_STATUS AcpiNsGetDeviceCallback ( ACPI_HANDLE  ObjHandle, UINT32  NestingLevel, void *  Context, void **  ReturnValue  )

static

Definition at line 731 of file nsxfeval.c.

{
    ACPI_GET_DEVICES_INFO   *Info = Context;
    ACPI_STATUS             Status;
    ACPI_NAMESPACE_NODE     *Node;
    UINT32                  Flags;
    ACPI_PNP_DEVICE_ID      *Hid;
    ACPI_PNP_DEVICE_ID_LIST *Cid;
    UINT32                  i;
    BOOLEAN                 Found;
    int                     NoMatch;
 
 
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return (Status);
    }
 
    Node = AcpiNsValidateHandle (ObjHandle);
    Status = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        return (Status);
    }
 
    if (!Node)
    {
        return (AE_BAD_PARAMETER);
    }
 
    /*
     * First, filter based on the device HID and CID.
     *
     * 01/2010: For this case where a specific HID is requested, we don't
     * want to run _STA until we have an actual HID match. Thus, we will
     * not unnecessarily execute _STA on devices for which the caller
     * doesn't care about. Previously, _STA was executed unconditionally
     * on all devices found here.
     *
     * A side-effect of this change is that now we will continue to search
     * for a matching HID even under device trees where the parent device
     * would have returned a _STA that indicates it is not present or
     * not functioning (thus aborting the search on that branch).
     */
    if (Info->Hid != NULL)
    {
        Status = AcpiUtExecute_HID (Node, &Hid);
        if (Status == AE_NOT_FOUND)
        {
            return (AE_OK);
        }
        else if (ACPI_FAILURE (Status))
        {
            return (AE_CTRL_DEPTH);
        }
 
        NoMatch = strcmp (Hid->String, Info->Hid);
        ACPI_FREE (Hid);
 
        if (NoMatch)
        {
            /*
             * HID does not match, attempt match within the
             * list of Compatible IDs (CIDs)
             */
            Status = AcpiUtExecute_CID (Node, &Cid);
            if (Status == AE_NOT_FOUND)
            {
                return (AE_OK);
            }
            else if (ACPI_FAILURE (Status))
            {
                return (AE_CTRL_DEPTH);
            }
 
            /* Walk the CID list */
 
            Found = FALSE;
            for (i = 0; i < Cid->Count; i++)
            {
                if (strcmp (Cid->Ids[i].String, Info->Hid) == 0)
                {
                    /* Found a matching CID */
 
                    Found = TRUE;
                    break;
                }
            }
 
            ACPI_FREE (Cid);
            if (!Found)
            {
                return (AE_OK);
            }
        }
    }
 
    /* Run _STA to determine if device is present */
 
    Status = AcpiUtExecute_STA (Node, &Flags);
    if (ACPI_FAILURE (Status))
    {
        return (AE_CTRL_DEPTH);
    }
 
    if (!(Flags & ACPI_STA_DEVICE_PRESENT) &&
        !(Flags & ACPI_STA_DEVICE_FUNCTIONING))
    {
        /*
         * Don't examine the children of the device only when the
         * device is neither present nor functional. See ACPI spec,
         * description of _STA for more information.
         */
        return (AE_CTRL_DEPTH);
    }
 
    /* We have a valid device, invoke the user function */
 
    Status = Info->UserFunction (ObjHandle, NestingLevel,
        Info->Context, ReturnValue);
    return (Status);
}

Referenced by AcpiGetDevices().

AcpiNsResolveReferences()

static void AcpiNsResolveReferences ( ACPI_EVALUATE_INFO *  Info )

static

Definition at line 551 of file nsxfeval.c.

{
    ACPI_OPERAND_OBJECT     *ObjDesc = NULL;
    ACPI_NAMESPACE_NODE     *Node;
 
 
    /* We are interested in reference objects only */
 
    if ((Info->ReturnObject)->Common.Type != ACPI_TYPE_LOCAL_REFERENCE)
    {
        return;
    }
 
    /*
     * Two types of references are supported - those created by Index and
     * RefOf operators. A name reference (AML_NAMEPATH_OP) can be converted
     * to an ACPI_OBJECT, so it is not dereferenced here. A DdbHandle
     * (AML_LOAD_OP) cannot be dereferenced, nor can it be converted to
     * an ACPI_OBJECT.
     */
    switch (Info->ReturnObject->Reference.Class)
    {
    case ACPI_REFCLASS_INDEX:
 
        ObjDesc = *(Info->ReturnObject->Reference.Where);
        break;
 
    case ACPI_REFCLASS_REFOF:
 
        Node = Info->ReturnObject->Reference.Object;
        if (Node)
        {
            ObjDesc = Node->Object;
        }
        break;
 
    default:
 
        return;
    }
 
    /* Replace the existing reference object */
 
    if (ObjDesc)
    {
        AcpiUtAddReference (ObjDesc);
        AcpiUtRemoveReference (Info->ReturnObject);
        Info->ReturnObject = ObjDesc;
    }
 
    return;
}

Referenced by AcpiEvaluateObject().

AcpiWalkNamespace()

ACPI_STATUS AcpiWalkNamespace	(	ACPI_OBJECT_TYPE	Type,
		ACPI_HANDLE	StartObject,
		UINT32	MaxDepth,
		ACPI_WALK_CALLBACK	DescendingCallback,
		ACPI_WALK_CALLBACK	AscendingCallback,
		void *	Context,
		void **	ReturnValue
	)

Definition at line 640 of file nsxfeval.c.

{
    ACPI_STATUS             Status;
 
 
    ACPI_FUNCTION_TRACE (AcpiWalkNamespace);
 
 
    /* Parameter validation */
 
    if ((Type > ACPI_TYPE_LOCAL_MAX) ||
        (!MaxDepth)                  ||
        (!DescendingCallback && !AscendingCallback))
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    /*
     * Need to acquire the namespace reader lock to prevent interference
     * with any concurrent table unloads (which causes the deletion of
     * namespace objects). We cannot allow the deletion of a namespace node
     * while the user function is using it. The exception to this are the
     * nodes created and deleted during control method execution -- these
     * nodes are marked as temporary nodes and are ignored by the namespace
     * walk. Thus, control methods can be executed while holding the
     * namespace deletion lock (and the user function can execute control
     * methods.)
     */
    Status = AcpiUtAcquireReadLock (&AcpiGbl_NamespaceRwLock);
    if (ACPI_FAILURE (Status))
    {
        return_ACPI_STATUS (Status);
    }
 
    /*
     * Lock the namespace around the walk. The namespace will be
     * unlocked/locked around each call to the user function - since the user
     * function must be allowed to make ACPICA calls itself (for example, it
     * will typically execute control methods during device enumeration.)
     */
    Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    if (ACPI_FAILURE (Status))
    {
        goto UnlockAndExit;
    }
 
    /* Now we can validate the starting node */
 
    if (!AcpiNsValidateHandle (StartObject))
    {
        Status = AE_BAD_PARAMETER;
        goto UnlockAndExit2;
    }
 
    Status = AcpiNsWalkNamespace (Type, StartObject, MaxDepth,
        ACPI_NS_WALK_UNLOCK, DescendingCallback,
        AscendingCallback, Context, ReturnValue);
 
UnlockAndExit2:
    (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
 
UnlockAndExit:
    (void) AcpiUtReleaseReadLock (&AcpiGbl_NamespaceRwLock);
    return_ACPI_STATUS (Status);
}

Referenced by AcpiNsInitializeObjects(), and AcpiWalkNamespace().