// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
 *
 * Module Name: nsobject - Utilities for objects attached to namespace
 *                         table entries
 *
 ******************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsobject")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_attach_object
 *
 * PARAMETERS:  node                - Parent Node
 *              object              - Object to be attached
 *              type                - Type of object, or ACPI_TYPE_ANY if not
 *                                    known
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Record the given object as the value associated with the
 *              name whose acpi_handle is passed. If Object is NULL
 *              and Type is ACPI_TYPE_ANY, set the name as having no value.
 *              Note: Future may require that the Node->Flags field be passed
 *              as a parameter.
 *
 * MUTEX:       Assumes namespace is locked
 *
 ******************************************************************************/
acpi_status
acpi_ns_attach_object(struct acpi_namespace_node *node,
                      union acpi_operand_object *object, acpi_object_type type)
{
        union acpi_operand_object *obj_desc;
        union acpi_operand_object *last_obj_desc;
        acpi_object_type object_type = ACPI_TYPE_ANY;

        ACPI_FUNCTION_TRACE(ns_attach_object);

        /*
         * Parameter validation
         */
        if (!node) {

                /* Invalid handle */

                ACPI_ERROR((AE_INFO, "Null NamedObj handle"));
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        if (!object && (ACPI_TYPE_ANY != type)) {

                /* Null object */

                ACPI_ERROR((AE_INFO,
                            "Null object, but type not ACPI_TYPE_ANY"));
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        if (ACPI_GET_DESCRIPTOR_TYPE(node) != ACPI_DESC_TYPE_NAMED) {

                /* Not a name handle */

                ACPI_ERROR((AE_INFO, "Invalid handle %p [%s]",
                            node, acpi_ut_get_descriptor_name(node)));
                return_ACPI_STATUS(AE_BAD_PARAMETER);
        }

        /* Check if this object is already attached */

        if (node->object == object) {
                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                                  "Obj %p already installed in NameObj %p\n",
                                  object, node));

                return_ACPI_STATUS(AE_OK);
        }

        /* If null object, we will just install it */

        if (!object) {
                obj_desc = NULL;
                object_type = ACPI_TYPE_ANY;
        }

        /*
         * If the source object is a namespace Node with an attached object,
         * we will use that (attached) object
         */
        else if ((ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) &&
                 ((struct acpi_namespace_node *)object)->object) {
                /*
                 * Value passed is a name handle and that name has a
                 * non-null value. Use that name's value and type.
                 */
                obj_desc = ((struct acpi_namespace_node *)object)->object;
                object_type = ((struct acpi_namespace_node *)object)->type;
        }

        /*
         * Otherwise, we will use the parameter object, but we must type
         * it first
         */
        else {
                obj_desc = (union acpi_operand_object *)object;

                /* Use the given type */

                object_type = type;
        }

        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Installing %p into Node %p [%4.4s]\n",
                          obj_desc, node, acpi_ut_get_node_name(node)));

        /* Detach an existing attached object if present */

        if (node->object) {
                acpi_ns_detach_object(node);
        }

        if (obj_desc) {
                /*
                 * Must increment the new value's reference count
                 * (if it is an internal object)
                 */
                acpi_ut_add_reference(obj_desc);

                /*
                 * Handle objects with multiple descriptors - walk
                 * to the end of the descriptor list
                 */
                last_obj_desc = obj_desc;
                while (last_obj_desc->common.next_object) {
                        last_obj_desc = last_obj_desc->common.next_object;
                }

                /* Install the object at the front of the object list */

                last_obj_desc->common.next_object = node->object;
        }

        node->type = (u8) object_type;
        node->object = obj_desc;

        return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_detach_object
 *
 * PARAMETERS:  node           - A Namespace node whose object will be detached
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Detach/delete an object associated with a namespace node.
 *              if the object is an allocated object, it is freed.
 *              Otherwise, the field is simply cleared.
 *
 ******************************************************************************/

void acpi_ns_detach_object(struct acpi_namespace_node *node)
{
        union acpi_operand_object *obj_desc;

        ACPI_FUNCTION_TRACE(ns_detach_object);

        obj_desc = node->object;

        if (!obj_desc || (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA)) {
                return_VOID;
        }

        if (node->flags & ANOBJ_ALLOCATED_BUFFER) {

                /* Free the dynamic aml buffer */

                if (obj_desc->common.type == ACPI_TYPE_METHOD) {
                        ACPI_FREE(obj_desc->method.aml_start);
                }
        }

        /* Clear the Node entry in all cases */

        node->object = NULL;
        if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) == ACPI_DESC_TYPE_OPERAND) {

                /* Unlink object from front of possible object list */

                node->object = obj_desc->common.next_object;

                /* Handle possible 2-descriptor object */

                if (node->object &&
                    (node->object->common.type != ACPI_TYPE_LOCAL_DATA)) {
                        node->object = node->object->common.next_object;
                }

                /*
                 * Detach the object from any data objects (which are still held by
                 * the namespace node)
                 */
                if (obj_desc->common.next_object &&
                    ((obj_desc->common.next_object)->common.type ==
                     ACPI_TYPE_LOCAL_DATA)) {
                        obj_desc->common.next_object = NULL;
                }
        }

        /* Reset the node type to untyped */

        node->type = ACPI_TYPE_ANY;

        ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Node %p [%4.4s] Object %p\n",
                          node, acpi_ut_get_node_name(node), obj_desc));

        /* Remove one reference on the object (and all subobjects) */

        acpi_ut_remove_reference(obj_desc);
        return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_attached_object
 *
 * PARAMETERS:  node             - Namespace node
 *
 * RETURN:      Current value of the object field from the Node whose
 *              handle is passed
 *
 * DESCRIPTION: Obtain the object attached to a namespace node.
 *
 ******************************************************************************/

union acpi_operand_object *acpi_ns_get_attached_object(struct
                                                       acpi_namespace_node
                                                       *node)
{
        ACPI_FUNCTION_TRACE_PTR(ns_get_attached_object, node);

        if (!node) {
                ACPI_WARNING((AE_INFO, "Null Node ptr"));
                return_PTR(NULL);
        }

        if (!node->object ||
            ((ACPI_GET_DESCRIPTOR_TYPE(node->object) != ACPI_DESC_TYPE_OPERAND)
             && (ACPI_GET_DESCRIPTOR_TYPE(node->object) !=
                 ACPI_DESC_TYPE_NAMED))
            || ((node->object)->common.type == ACPI_TYPE_LOCAL_DATA)) {
                return_PTR(NULL);
        }

        return_PTR(node->object);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_secondary_object
 *
 * PARAMETERS:  node             - Namespace node
 *
 * RETURN:      Current value of the object field from the Node whose
 *              handle is passed.
 *
 * DESCRIPTION: Obtain a secondary object associated with a namespace node.
 *
 ******************************************************************************/

union acpi_operand_object *acpi_ns_get_secondary_object(union
                                                        acpi_operand_object
                                                        *obj_desc)
{
        ACPI_FUNCTION_TRACE_PTR(ns_get_secondary_object, obj_desc);

        if ((!obj_desc) ||
            (obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) ||
            (!obj_desc->common.next_object) ||
            ((obj_desc->common.next_object)->common.type ==
             ACPI_TYPE_LOCAL_DATA)) {
                return_PTR(NULL);
        }

        return_PTR(obj_desc->common.next_object);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_attach_data
 *
 * PARAMETERS:  node            - Namespace node
 *              handler         - Handler to be associated with the data
 *              data            - Data to be attached
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Low-level attach data. Create and attach a Data object.
 *
 ******************************************************************************/

acpi_status
acpi_ns_attach_data(struct acpi_namespace_node *node,
                    acpi_object_handler handler, void *data)
{
        union acpi_operand_object *prev_obj_desc;
        union acpi_operand_object *obj_desc;
        union acpi_operand_object *data_desc;

        /* We only allow one attachment per handler */

        prev_obj_desc = NULL;
        obj_desc = node->object;
        while (obj_desc) {
                if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
                    (obj_desc->data.handler == handler)) {
                        return (AE_ALREADY_EXISTS);
                }

                prev_obj_desc = obj_desc;
                obj_desc = obj_desc->common.next_object;
        }

        /* Create an internal object for the data */

        data_desc = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_DATA);
        if (!data_desc) {
                return (AE_NO_MEMORY);
        }

        data_desc->data.handler = handler;
        data_desc->data.pointer = data;

        /* Install the data object */

        if (prev_obj_desc) {
                prev_obj_desc->common.next_object = data_desc;
        } else {
                node->object = data_desc;
        }

        return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_detach_data
 *
 * PARAMETERS:  node            - Namespace node
 *              handler         - Handler associated with the data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Low-level detach data. Delete the data node, but the caller
 *              is responsible for the actual data.
 *
 ******************************************************************************/

acpi_status
acpi_ns_detach_data(struct acpi_namespace_node *node,
                    acpi_object_handler handler)
{
        union acpi_operand_object *obj_desc;
        union acpi_operand_object *prev_obj_desc;

        prev_obj_desc = NULL;
        obj_desc = node->object;
        while (obj_desc) {
                if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
                    (obj_desc->data.handler == handler)) {
                        if (prev_obj_desc) {
                                prev_obj_desc->common.next_object =
                                    obj_desc->common.next_object;
                        } else {
                                node->object = obj_desc->common.next_object;
                        }

                        acpi_ut_remove_reference(obj_desc);
                        return (AE_OK);
                }

                prev_obj_desc = obj_desc;
                obj_desc = obj_desc->common.next_object;
        }

        return (AE_NOT_FOUND);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_get_attached_data
 *
 * PARAMETERS:  node            - Namespace node
 *              handler         - Handler associated with the data
 *              data            - Where the data is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Low level interface to obtain data previously associated with
 *              a namespace node.
 *
 ******************************************************************************/

acpi_status
acpi_ns_get_attached_data(struct acpi_namespace_node *node,
                          acpi_object_handler handler, void **data)
{
        union acpi_operand_object *obj_desc;

        obj_desc = node->object;
        while (obj_desc) {
                if ((obj_desc->common.type == ACPI_TYPE_LOCAL_DATA) &&
                    (obj_desc->data.handler == handler)) {
                        *data = obj_desc->data.pointer;
                        return (AE_OK);
                }

                obj_desc = obj_desc->common.next_object;
        }

        return (AE_NOT_FOUND);
}