exstore.c

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/******************************************************************************
 *
 * Module Name: exstore - AML Interpreter object store support
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, 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/acpi.h>
#include "accommon.h"
#include "acdispat.h"
#include "acinterp.h"
#include "amlcode.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_EXECUTER
ACPI_MODULE_NAME("exstore")

/* Local prototypes */
static acpi_status
acpi_ex_store_object_to_index(union acpi_operand_object *val_desc,
                  union acpi_operand_object *dest_desc,
                  struct acpi_walk_state *walk_state);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store
 *
 * PARAMETERS:  *source_desc        - Value to be stored
 *              *dest_desc          - Where to store it. Must be an NS node
 *                                    or union acpi_operand_object of type
 *                                    Reference;
 *              walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Store the value described by source_desc into the location
 *              described by dest_desc. Called by various interpreter
 *              functions to store the result of an operation into
 *              the destination operand -- not just simply the actual "Store"
 *              ASL operator.
 *
 ******************************************************************************/

acpi_status
acpi_ex_store(union acpi_operand_object *source_desc,
          union acpi_operand_object *dest_desc,
          struct acpi_walk_state *walk_state)
{
    acpi_status status = AE_OK;
    union acpi_operand_object *ref_desc = dest_desc;

    ACPI_FUNCTION_TRACE_PTR(ex_store, dest_desc);

    /* Validate parameters */

    if (!source_desc || !dest_desc) {
        ACPI_ERROR((AE_INFO, "Null parameter"));
        return_ACPI_STATUS(AE_AML_NO_OPERAND);
    }

    /* dest_desc can be either a namespace node or an ACPI object */

    if (ACPI_GET_DESCRIPTOR_TYPE(dest_desc) == ACPI_DESC_TYPE_NAMED) {
        /*
         * Dest is a namespace node,
         * Storing an object into a Named node.
         */
        status = acpi_ex_store_object_to_node(source_desc,
                              (struct
                               acpi_namespace_node *)
                              dest_desc, walk_state,
                              ACPI_IMPLICIT_CONVERSION);

        return_ACPI_STATUS(status);
    }

    /* Destination object must be a Reference or a Constant object */

    switch (dest_desc->common.type) {
    case ACPI_TYPE_LOCAL_REFERENCE:
        break;

    case ACPI_TYPE_INTEGER:

        /* Allow stores to Constants -- a Noop as per ACPI spec */

        if (dest_desc->common.flags & AOPOBJ_AML_CONSTANT) {
            return_ACPI_STATUS(AE_OK);
        }

        /*lint -fallthrough */

    default:

        /* Destination is not a Reference object */

        ACPI_ERROR((AE_INFO,
                "Target is not a Reference or Constant object - %s [%p]",
                acpi_ut_get_object_type_name(dest_desc),
                dest_desc));

        return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
    }

    /*
     * Examine the Reference class. These cases are handled:
     *
     * 1) Store to Name (Change the object associated with a name)
     * 2) Store to an indexed area of a Buffer or Package
     * 3) Store to a Method Local or Arg
     * 4) Store to the debug object
     */
    switch (ref_desc->reference.class) {
    case ACPI_REFCLASS_REFOF:

        /* Storing an object into a Name "container" */

        status = acpi_ex_store_object_to_node(source_desc,
                              ref_desc->reference.
                              object, walk_state,
                              ACPI_IMPLICIT_CONVERSION);
        break;

    case ACPI_REFCLASS_INDEX:

        /* Storing to an Index (pointer into a packager or buffer) */

        status =
            acpi_ex_store_object_to_index(source_desc, ref_desc,
                          walk_state);
        break;

    case ACPI_REFCLASS_LOCAL:
    case ACPI_REFCLASS_ARG:

        /* Store to a method local/arg  */

        status =
            acpi_ds_store_object_to_local(ref_desc->reference.class,
                          ref_desc->reference.value,
                          source_desc, walk_state);
        break;

    case ACPI_REFCLASS_DEBUG:

        /*
         * Storing to the Debug object causes the value stored to be
         * displayed and otherwise has no effect -- see ACPI Specification
         */
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                  "**** Write to Debug Object: Object %p %s ****:\n\n",
                  source_desc,
                  acpi_ut_get_object_type_name(source_desc)));

        ACPI_DEBUG_OBJECT(source_desc, 0, 0);
        break;

    default:

        ACPI_ERROR((AE_INFO, "Unknown Reference Class 0x%2.2X",
                ref_desc->reference.class));
        ACPI_DUMP_ENTRY(ref_desc, ACPI_LV_INFO);

        status = AE_AML_INTERNAL;
        break;
    }

    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store_object_to_index
 *
 * PARAMETERS:  *source_desc            - Value to be stored
 *              *dest_desc              - Named object to receive the value
 *              walk_state              - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Store the object to indexed Buffer or Package element
 *
 ******************************************************************************/

static acpi_status
acpi_ex_store_object_to_index(union acpi_operand_object *source_desc,
                  union acpi_operand_object *index_desc,
                  struct acpi_walk_state *walk_state)
{
    acpi_status status = AE_OK;
    union acpi_operand_object *obj_desc;
    union acpi_operand_object *new_desc;
    u8 value = 0;
    u32 i;

    ACPI_FUNCTION_TRACE(ex_store_object_to_index);

    /*
     * Destination must be a reference pointer, and
     * must point to either a buffer or a package
     */
    switch (index_desc->reference.target_type) {
    case ACPI_TYPE_PACKAGE:
        /*
         * Storing to a package element. Copy the object and replace
         * any existing object with the new object. No implicit
         * conversion is performed.
         *
         * The object at *(index_desc->Reference.Where) is the
         * element within the package that is to be modified.
         * The parent package object is at index_desc->Reference.Object
         */
        obj_desc = *(index_desc->reference.where);

        if (source_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE &&
            source_desc->reference.class == ACPI_REFCLASS_TABLE) {

            /* This is a DDBHandle, just add a reference to it */

            acpi_ut_add_reference(source_desc);
            new_desc = source_desc;
        } else {
            /* Normal object, copy it */

            status =
                acpi_ut_copy_iobject_to_iobject(source_desc,
                                &new_desc,
                                walk_state);
            if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
            }
        }

        if (obj_desc) {

            /* Decrement reference count by the ref count of the parent package */

            for (i = 0; i < ((union acpi_operand_object *)
                     index_desc->reference.object)->common.
                 reference_count; i++) {
                acpi_ut_remove_reference(obj_desc);
            }
        }

        *(index_desc->reference.where) = new_desc;

        /* Increment ref count by the ref count of the parent package-1 */

        for (i = 1; i < ((union acpi_operand_object *)
                 index_desc->reference.object)->common.
             reference_count; i++) {
            acpi_ut_add_reference(new_desc);
        }

        break;

    case ACPI_TYPE_BUFFER_FIELD:

        /*
         * Store into a Buffer or String (not actually a real buffer_field)
         * at a location defined by an Index.
         *
         * The first 8-bit element of the source object is written to the
         * 8-bit Buffer location defined by the Index destination object,
         * according to the ACPI 2.0 specification.
         */

        /*
         * Make sure the target is a Buffer or String. An error should
         * not happen here, since the reference_object was constructed
         * by the INDEX_OP code.
         */
        obj_desc = index_desc->reference.object;
        if ((obj_desc->common.type != ACPI_TYPE_BUFFER) &&
            (obj_desc->common.type != ACPI_TYPE_STRING)) {
            return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
        }

        /*
         * The assignment of the individual elements will be slightly
         * different for each source type.
         */
        switch (source_desc->common.type) {
        case ACPI_TYPE_INTEGER:

            /* Use the least-significant byte of the integer */

            value = (u8) (source_desc->integer.value);
            break;

        case ACPI_TYPE_BUFFER:
        case ACPI_TYPE_STRING:

            /* Note: Takes advantage of common string/buffer fields */

            value = source_desc->buffer.pointer[0];
            break;

        default:

            /* All other types are invalid */

            ACPI_ERROR((AE_INFO,
                    "Source must be Integer/Buffer/String type, not %s",
                    acpi_ut_get_object_type_name(source_desc)));
            return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
        }

        /* Store the source value into the target buffer byte */

        obj_desc->buffer.pointer[index_desc->reference.value] = value;
        break;

    default:
        ACPI_ERROR((AE_INFO, "Target is not a Package or BufferField"));
        status = AE_AML_OPERAND_TYPE;
        break;
    }

    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_store_object_to_node
 *
 * PARAMETERS:  source_desc             - Value to be stored
 *              node                    - Named object to receive the value
 *              walk_state              - Current walk state
 *              implicit_conversion     - Perform implicit conversion (yes/no)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Store the object to the named object.
 *
 *              The Assignment of an object to a named object is handled here
 *              The value passed in will replace the current value (if any)
 *              with the input value.
 *
 *              When storing into an object the data is converted to the
 *              target object type then stored in the object.  This means
 *              that the target object type (for an initialized target) will
 *              not be changed by a store operation.
 *
 *              Assumes parameters are already validated.
 *
 ******************************************************************************/

acpi_status
acpi_ex_store_object_to_node(union acpi_operand_object *source_desc,
                 struct acpi_namespace_node *node,
                 struct acpi_walk_state *walk_state,
                 u8 implicit_conversion)
{
    acpi_status status = AE_OK;
    union acpi_operand_object *target_desc;
    union acpi_operand_object *new_desc;
    acpi_object_type target_type;

    ACPI_FUNCTION_TRACE_PTR(ex_store_object_to_node, source_desc);

    /* Get current type of the node, and object attached to Node */

    target_type = acpi_ns_get_type(node);
    target_desc = acpi_ns_get_attached_object(node);

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Storing %p(%s) into node %p(%s)\n",
              source_desc,
              acpi_ut_get_object_type_name(source_desc), node,
              acpi_ut_get_type_name(target_type)));

    /*
     * Resolve the source object to an actual value
     * (If it is a reference object)
     */
    status = acpi_ex_resolve_object(&source_desc, target_type, walk_state);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* If no implicit conversion, drop into the default case below */

    if ((!implicit_conversion) ||
        ((walk_state->opcode == AML_COPY_OP) &&
         (target_type != ACPI_TYPE_LOCAL_REGION_FIELD) &&
         (target_type != ACPI_TYPE_LOCAL_BANK_FIELD) &&
         (target_type != ACPI_TYPE_LOCAL_INDEX_FIELD))) {
        /*
         * Force execution of default (no implicit conversion). Note:
         * copy_object does not perform an implicit conversion, as per the ACPI
         * spec -- except in case of region/bank/index fields -- because these
         * objects must retain their original type permanently.
         */
        target_type = ACPI_TYPE_ANY;
    }

    /* Do the actual store operation */

    switch (target_type) {
    case ACPI_TYPE_BUFFER_FIELD:
    case ACPI_TYPE_LOCAL_REGION_FIELD:
    case ACPI_TYPE_LOCAL_BANK_FIELD:
    case ACPI_TYPE_LOCAL_INDEX_FIELD:

        /* For fields, copy the source data to the target field. */

        status = acpi_ex_write_data_to_field(source_desc, target_desc,
                             &walk_state->result_obj);
        break;

    case ACPI_TYPE_INTEGER:
    case ACPI_TYPE_STRING:
    case ACPI_TYPE_BUFFER:

        /*
         * These target types are all of type Integer/String/Buffer, and
         * therefore support implicit conversion before the store.
         *
         * Copy and/or convert the source object to a new target object
         */
        status =
            acpi_ex_store_object_to_object(source_desc, target_desc,
                           &new_desc, walk_state);
        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }

        if (new_desc != target_desc) {
            /*
             * Store the new new_desc as the new value of the Name, and set
             * the Name's type to that of the value being stored in it.
             * source_desc reference count is incremented by attach_object.
             *
             * Note: This may change the type of the node if an explicit store
             * has been performed such that the node/object type has been
             * changed.
             */
            status =
                acpi_ns_attach_object(node, new_desc,
                          new_desc->common.type);

            ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                      "Store %s into %s via Convert/Attach\n",
                      acpi_ut_get_object_type_name
                      (source_desc),
                      acpi_ut_get_object_type_name
                      (new_desc)));
        }
        break;

    default:

        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                  "Storing %s (%p) directly into node (%p) with no implicit conversion\n",
                  acpi_ut_get_object_type_name(source_desc),
                  source_desc, node));

        /* No conversions for all other types.  Just attach the source object */

        status = acpi_ns_attach_object(node, source_desc,
                           source_desc->common.type);
        break;
    }

    return_ACPI_STATUS(status);
}