dsmthdat.c

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/*******************************************************************************
 *
 * Module Name: dsmthdat - control method arguments and local variables
 *
 ******************************************************************************/

/*
 * 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 "acnamesp.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_DISPATCHER
ACPI_MODULE_NAME("dsmthdat")

/* Local prototypes */
static void
acpi_ds_method_data_delete_value(u8 type,
                 u32 index, struct acpi_walk_state *walk_state);

static acpi_status
acpi_ds_method_data_set_value(u8 type,
                  u32 index,
                  union acpi_operand_object *object,
                  struct acpi_walk_state *walk_state);

#ifdef ACPI_OBSOLETE_FUNCTIONS
acpi_object_type
acpi_ds_method_data_get_type(u16 opcode,
                 u32 index, struct acpi_walk_state *walk_state);
#endif

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_init
 *
 * PARAMETERS:  walk_state          - Current walk state object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize the data structures that hold the method's arguments
 *              and locals.  The data struct is an array of namespace nodes for
 *              each - this allows ref_of and de_ref_of to work properly for these
 *              special data types.
 *
 * NOTES:       walk_state fields are initialized to zero by the
 *              ACPI_ALLOCATE_ZEROED().
 *
 *              A pseudo-Namespace Node is assigned to each argument and local
 *              so that ref_of() can return a pointer to the Node.
 *
 ******************************************************************************/

void acpi_ds_method_data_init(struct acpi_walk_state *walk_state)
{
    u32 i;

    ACPI_FUNCTION_TRACE(ds_method_data_init);

    /* Init the method arguments */

    for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++) {
        ACPI_MOVE_32_TO_32(&walk_state->arguments[i].name,
                   NAMEOF_ARG_NTE);
        walk_state->arguments[i].name.integer |= (i << 24);
        walk_state->arguments[i].descriptor_type = ACPI_DESC_TYPE_NAMED;
        walk_state->arguments[i].type = ACPI_TYPE_ANY;
        walk_state->arguments[i].flags = ANOBJ_METHOD_ARG;
    }

    /* Init the method locals */

    for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++) {
        ACPI_MOVE_32_TO_32(&walk_state->local_variables[i].name,
                   NAMEOF_LOCAL_NTE);

        walk_state->local_variables[i].name.integer |= (i << 24);
        walk_state->local_variables[i].descriptor_type =
            ACPI_DESC_TYPE_NAMED;
        walk_state->local_variables[i].type = ACPI_TYPE_ANY;
        walk_state->local_variables[i].flags = ANOBJ_METHOD_LOCAL;
    }

    return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_delete_all
 *
 * PARAMETERS:  walk_state          - Current walk state object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Delete method locals and arguments.  Arguments are only
 *              deleted if this method was called from another method.
 *
 ******************************************************************************/

void acpi_ds_method_data_delete_all(struct acpi_walk_state *walk_state)
{
    u32 index;

    ACPI_FUNCTION_TRACE(ds_method_data_delete_all);

    /* Detach the locals */

    for (index = 0; index < ACPI_METHOD_NUM_LOCALS; index++) {
        if (walk_state->local_variables[index].object) {
            ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Local%u=%p\n",
                      index,
                      walk_state->local_variables[index].
                      object));

            /* Detach object (if present) and remove a reference */

            acpi_ns_detach_object(&walk_state->
                          local_variables[index]);
        }
    }

    /* Detach the arguments */

    for (index = 0; index < ACPI_METHOD_NUM_ARGS; index++) {
        if (walk_state->arguments[index].object) {
            ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Deleting Arg%u=%p\n",
                      index,
                      walk_state->arguments[index].object));

            /* Detach object (if present) and remove a reference */

            acpi_ns_detach_object(&walk_state->arguments[index]);
        }
    }

    return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_init_args
 *
 * PARAMETERS:  *params         - Pointer to a parameter list for the method
 *              max_param_count - The arg count for this method
 *              walk_state      - Current walk state object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize arguments for a method.  The parameter list is a list
 *              of ACPI operand objects, either null terminated or whose length
 *              is defined by max_param_count.
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_init_args(union acpi_operand_object **params,
                  u32 max_param_count,
                  struct acpi_walk_state *walk_state)
{
    acpi_status status;
    u32 index = 0;

    ACPI_FUNCTION_TRACE_PTR(ds_method_data_init_args, params);

    if (!params) {
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                  "No param list passed to method\n"));
        return_ACPI_STATUS(AE_OK);
    }

    /* Copy passed parameters into the new method stack frame */

    while ((index < ACPI_METHOD_NUM_ARGS) &&
           (index < max_param_count) && params[index]) {
        /*
         * A valid parameter.
         * Store the argument in the method/walk descriptor.
         * Do not copy the arg in order to implement call by reference
         */
        status = acpi_ds_method_data_set_value(ACPI_REFCLASS_ARG, index,
                               params[index],
                               walk_state);
        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }

        index++;
    }

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%u args passed to method\n", index));
    return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_node
 *
 * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
 *                                    ACPI_REFCLASS_ARG
 *              index               - Which Local or Arg whose type to get
 *              walk_state          - Current walk state object
 *              node                - Where the node is returned.
 *
 * RETURN:      Status and node
 *
 * DESCRIPTION: Get the Node associated with a local or arg.
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_get_node(u8 type,
                 u32 index,
                 struct acpi_walk_state *walk_state,
                 struct acpi_namespace_node **node)
{
    ACPI_FUNCTION_TRACE(ds_method_data_get_node);

    /*
     * Method Locals and Arguments are supported
     */
    switch (type) {
    case ACPI_REFCLASS_LOCAL:

        if (index > ACPI_METHOD_MAX_LOCAL) {
            ACPI_ERROR((AE_INFO,
                    "Local index %u is invalid (max %u)",
                    index, ACPI_METHOD_MAX_LOCAL));
            return_ACPI_STATUS(AE_AML_INVALID_INDEX);
        }

        /* Return a pointer to the pseudo-node */

        *node = &walk_state->local_variables[index];
        break;

    case ACPI_REFCLASS_ARG:

        if (index > ACPI_METHOD_MAX_ARG) {
            ACPI_ERROR((AE_INFO,
                    "Arg index %u is invalid (max %u)",
                    index, ACPI_METHOD_MAX_ARG));
            return_ACPI_STATUS(AE_AML_INVALID_INDEX);
        }

        /* Return a pointer to the pseudo-node */

        *node = &walk_state->arguments[index];
        break;

    default:
        ACPI_ERROR((AE_INFO, "Type %u is invalid", type));
        return_ACPI_STATUS(AE_TYPE);
    }

    return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_set_value
 *
 * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
 *                                    ACPI_REFCLASS_ARG
 *              index               - Which Local or Arg to get
 *              object              - Object to be inserted into the stack entry
 *              walk_state          - Current walk state object
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Insert an object onto the method stack at entry Opcode:Index.
 *              Note: There is no "implicit conversion" for locals.
 *
 ******************************************************************************/

static acpi_status
acpi_ds_method_data_set_value(u8 type,
                  u32 index,
                  union acpi_operand_object *object,
                  struct acpi_walk_state *walk_state)
{
    acpi_status status;
    struct acpi_namespace_node *node;

    ACPI_FUNCTION_TRACE(ds_method_data_set_value);

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
              "NewObj %p Type %2.2X, Refs=%u [%s]\n", object,
              type, object->common.reference_count,
              acpi_ut_get_type_name(object->common.type)));

    /* Get the namespace node for the arg/local */

    status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /*
     * Increment ref count so object can't be deleted while installed.
     * NOTE: We do not copy the object in order to preserve the call by
     * reference semantics of ACPI Control Method invocation.
     * (See ACPI Specification 2.0C)
     */
    acpi_ut_add_reference(object);

    /* Install the object */

    node->object = object;
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_value
 *
 * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
 *                                    ACPI_REFCLASS_ARG
 *              index               - Which localVar or argument to get
 *              walk_state          - Current walk state object
 *              dest_desc           - Where Arg or Local value is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Retrieve value of selected Arg or Local for this method
 *              Used only in acpi_ex_resolve_to_value().
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_get_value(u8 type,
                  u32 index,
                  struct acpi_walk_state *walk_state,
                  union acpi_operand_object **dest_desc)
{
    acpi_status status;
    struct acpi_namespace_node *node;
    union acpi_operand_object *object;

    ACPI_FUNCTION_TRACE(ds_method_data_get_value);

    /* Validate the object descriptor */

    if (!dest_desc) {
        ACPI_ERROR((AE_INFO, "Null object descriptor pointer"));
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /* Get the namespace node for the arg/local */

    status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Get the object from the node */

    object = node->object;

    /* Examine the returned object, it must be valid. */

    if (!object) {
        /*
         * Index points to uninitialized object.
         * This means that either 1) The expected argument was
         * not passed to the method, or 2) A local variable
         * was referenced by the method (via the ASL)
         * before it was initialized.  Either case is an error.
         */

        /* If slack enabled, init the local_x/arg_x to an Integer of value zero */

        if (acpi_gbl_enable_interpreter_slack) {
            object = acpi_ut_create_integer_object((u64) 0);
            if (!object) {
                return_ACPI_STATUS(AE_NO_MEMORY);
            }

            node->object = object;
        }

        /* Otherwise, return the error */

        else
            switch (type) {
            case ACPI_REFCLASS_ARG:

                ACPI_ERROR((AE_INFO,
                        "Uninitialized Arg[%u] at node %p",
                        index, node));

                return_ACPI_STATUS(AE_AML_UNINITIALIZED_ARG);

            case ACPI_REFCLASS_LOCAL:

                /*
                 * No error message for this case, will be trapped again later to
                 * detect and ignore cases of Store(local_x,local_x)
                 */
                return_ACPI_STATUS(AE_AML_UNINITIALIZED_LOCAL);

            default:

                ACPI_ERROR((AE_INFO,
                        "Not a Arg/Local opcode: 0x%X",
                        type));
                return_ACPI_STATUS(AE_AML_INTERNAL);
            }
    }

    /*
     * The Index points to an initialized and valid object.
     * Return an additional reference to the object
     */
    *dest_desc = object;
    acpi_ut_add_reference(object);

    return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_delete_value
 *
 * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
 *                                    ACPI_REFCLASS_ARG
 *              index               - Which localVar or argument to delete
 *              walk_state          - Current walk state object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Delete the entry at Opcode:Index.  Inserts
 *              a null into the stack slot after the object is deleted.
 *
 ******************************************************************************/

static void
acpi_ds_method_data_delete_value(u8 type,
                 u32 index, struct acpi_walk_state *walk_state)
{
    acpi_status status;
    struct acpi_namespace_node *node;
    union acpi_operand_object *object;

    ACPI_FUNCTION_TRACE(ds_method_data_delete_value);

    /* Get the namespace node for the arg/local */

    status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
    if (ACPI_FAILURE(status)) {
        return_VOID;
    }

    /* Get the associated object */

    object = acpi_ns_get_attached_object(node);

    /*
     * Undefine the Arg or Local by setting its descriptor
     * pointer to NULL. Locals/Args can contain both
     * ACPI_OPERAND_OBJECTS and ACPI_NAMESPACE_NODEs
     */
    node->object = NULL;

    if ((object) &&
        (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_OPERAND)) {
        /*
         * There is a valid object.
         * Decrement the reference count by one to balance the
         * increment when the object was stored.
         */
        acpi_ut_remove_reference(object);
    }

    return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_store_object_to_local
 *
 * PARAMETERS:  type                - Either ACPI_REFCLASS_LOCAL or
 *                                    ACPI_REFCLASS_ARG
 *              index               - Which Local or Arg to set
 *              obj_desc            - Value to be stored
 *              walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Store a value in an Arg or Local.  The obj_desc is installed
 *              as the new value for the Arg or Local and the reference count
 *              for obj_desc is incremented.
 *
 ******************************************************************************/

acpi_status
acpi_ds_store_object_to_local(u8 type,
                  u32 index,
                  union acpi_operand_object *obj_desc,
                  struct acpi_walk_state *walk_state)
{
    acpi_status status;
    struct acpi_namespace_node *node;
    union acpi_operand_object *current_obj_desc;
    union acpi_operand_object *new_obj_desc;

    ACPI_FUNCTION_TRACE(ds_store_object_to_local);
    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Type=%2.2X Index=%u Obj=%p\n",
              type, index, obj_desc));

    /* Parameter validation */

    if (!obj_desc) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /* Get the namespace node for the arg/local */

    status = acpi_ds_method_data_get_node(type, index, walk_state, &node);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    current_obj_desc = acpi_ns_get_attached_object(node);
    if (current_obj_desc == obj_desc) {
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p already installed!\n",
                  obj_desc));
        return_ACPI_STATUS(status);
    }

    /*
     * If the reference count on the object is more than one, we must
     * take a copy of the object before we store.  A reference count
     * of exactly 1 means that the object was just created during the
     * evaluation of an expression, and we can safely use it since it
     * is not used anywhere else.
     */
    new_obj_desc = obj_desc;
    if (obj_desc->common.reference_count > 1) {
        status =
            acpi_ut_copy_iobject_to_iobject(obj_desc, &new_obj_desc,
                            walk_state);
        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }
    }

    /*
     * If there is an object already in this slot, we either
     * have to delete it, or if this is an argument and there
     * is an object reference stored there, we have to do
     * an indirect store!
     */
    if (current_obj_desc) {
        /*
         * Check for an indirect store if an argument
         * contains an object reference (stored as an Node).
         * We don't allow this automatic dereferencing for
         * locals, since a store to a local should overwrite
         * anything there, including an object reference.
         *
         * If both Arg0 and Local0 contain ref_of (Local4):
         *
         * Store (1, Arg0)             - Causes indirect store to local4
         * Store (1, Local0)           - Stores 1 in local0, overwriting
         *                                  the reference to local4
         * Store (1, de_refof (Local0)) - Causes indirect store to local4
         *
         * Weird, but true.
         */
        if (type == ACPI_REFCLASS_ARG) {
            /*
             * If we have a valid reference object that came from ref_of(),
             * do the indirect store
             */
            if ((ACPI_GET_DESCRIPTOR_TYPE(current_obj_desc) ==
                 ACPI_DESC_TYPE_OPERAND)
                && (current_obj_desc->common.type ==
                ACPI_TYPE_LOCAL_REFERENCE)
                && (current_obj_desc->reference.class ==
                ACPI_REFCLASS_REFOF)) {
                ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                          "Arg (%p) is an ObjRef(Node), storing in node %p\n",
                          new_obj_desc,
                          current_obj_desc));

                /*
                 * Store this object to the Node (perform the indirect store)
                 * NOTE: No implicit conversion is performed, as per the ACPI
                 * specification rules on storing to Locals/Args.
                 */
                status =
                    acpi_ex_store_object_to_node(new_obj_desc,
                                 current_obj_desc->
                                 reference.
                                 object,
                                 walk_state,
                                 ACPI_NO_IMPLICIT_CONVERSION);

                /* Remove local reference if we copied the object above */

                if (new_obj_desc != obj_desc) {
                    acpi_ut_remove_reference(new_obj_desc);
                }
                return_ACPI_STATUS(status);
            }
        }

        /* Delete the existing object before storing the new one */

        acpi_ds_method_data_delete_value(type, index, walk_state);
    }

    /*
     * Install the Obj descriptor (*new_obj_desc) into
     * the descriptor for the Arg or Local.
     * (increments the object reference count by one)
     */
    status =
        acpi_ds_method_data_set_value(type, index, new_obj_desc,
                      walk_state);

    /* Remove local reference if we copied the object above */

    if (new_obj_desc != obj_desc) {
        acpi_ut_remove_reference(new_obj_desc);
    }

    return_ACPI_STATUS(status);
}

#ifdef ACPI_OBSOLETE_FUNCTIONS
/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_type
 *
 * PARAMETERS:  opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              index               - Which Local or Arg whose type to get
 *              walk_state          - Current walk state object
 *
 * RETURN:      Data type of current value of the selected Arg or Local
 *
 * DESCRIPTION: Get the type of the object stored in the Local or Arg
 *
 ******************************************************************************/

acpi_object_type
acpi_ds_method_data_get_type(u16 opcode,
                 u32 index, struct acpi_walk_state *walk_state)
{
    acpi_status status;
    struct acpi_namespace_node *node;
    union acpi_operand_object *object;

    ACPI_FUNCTION_TRACE(ds_method_data_get_type);

    /* Get the namespace node for the arg/local */

    status = acpi_ds_method_data_get_node(opcode, index, walk_state, &node);
    if (ACPI_FAILURE(status)) {
        return_VALUE((ACPI_TYPE_NOT_FOUND));
    }

    /* Get the object */

    object = acpi_ns_get_attached_object(node);
    if (!object) {

        /* Uninitialized local/arg, return TYPE_ANY */

        return_VALUE(ACPI_TYPE_ANY);
    }

    /* Get the object type */

    return_VALUE(object->type);
}
#endif