Linux-2.6.12-rc2

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / dispatcher / dsmthdat.c

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

/*
 * Copyright (C) 2000 - 2005, R. Byron Moore
 * 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 <acpi/acdispat.h>
#include <acpi/amlcode.h>
#include <acpi/acnamesp.h>
#include <acpi/acinterp.h>


#define _COMPONENT          ACPI_DISPATCHER
         ACPI_MODULE_NAME    ("dsmthdat")


/*******************************************************************************
 *
 * 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 NTEs 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_MEM_CALLOCATE().
 *
 *              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   = ACPI_DESC_TYPE_NAMED;
                walk_state->arguments[i].type         = ACPI_TYPE_ANY;
                walk_state->arguments[i].flags        = ANOBJ_END_OF_PEER_LIST | 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  = ACPI_DESC_TYPE_NAMED;
                walk_state->local_variables[i].type        = ACPI_TYPE_ANY;
                walk_state->local_variables[i].flags       = ANOBJ_END_OF_PEER_LIST | 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%d=%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%d=%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 (AML_ARG_OP, index, params[index], walk_state);
                if (ACPI_FAILURE (status)) {
                        return_ACPI_STATUS (status);
                }

                index++;
        }

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


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_node
 *
 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument whose type
 *                                      to get
 *              walk_state          - Current walk state object
 *
 * RETURN:      Get the Node associated with a local or arg.
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_get_node (
        u16                             opcode,
        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 (opcode) {
        case AML_LOCAL_OP:

                if (index > ACPI_METHOD_MAX_LOCAL) {
                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Local index %d is invalid (max %d)\n",
                                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 AML_ARG_OP:

                if (index > ACPI_METHOD_MAX_ARG) {
                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Arg index %d is invalid (max %d)\n",
                                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_DEBUG_PRINT ((ACPI_DB_ERROR, "Opcode %d is invalid\n", opcode));
                return_ACPI_STATUS (AE_AML_BAD_OPCODE);
        }

        return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_set_value
 *
 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument 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.
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_set_value (
        u16                             opcode,
        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,
                "new_obj %p Opcode %X, Refs=%d [%s]\n", object,
                opcode, 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 (opcode, 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 2.0_c)
         */
        acpi_ut_add_reference (object);

        /* Install the object */

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


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_type
 *
 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument whose type
 *                                      to get
 *              walk_state          - Current walk state object
 *
 * RETURN:      Data type of current value of the selected Arg or Local
 *
 ******************************************************************************/
#ifdef ACPI_FUTURE_USAGE
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 (ACPI_GET_OBJECT_TYPE (object));
}
#endif  /*  ACPI_FUTURE_USAGE  */


/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_method_data_get_value
 *
 * PARAMETERS:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument to get
 *              walk_state          - Current walk state object
 *              *dest_desc          - Ptr to Descriptor into which selected Arg
 *                                    or Local value should be copied
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Retrieve value of selected Arg or Local from the method frame
 *              at the current top of the method stack.
 *              Used only in acpi_ex_resolve_to_value().
 *
 ******************************************************************************/

acpi_status
acpi_ds_method_data_get_value (
        u16                             opcode,
        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_DEBUG_PRINT ((ACPI_DB_ERROR, "Null object descriptor pointer\n"));
                return_ACPI_STATUS (AE_BAD_PARAMETER);
        }

        /* 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_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_internal_object (ACPI_TYPE_INTEGER);
                        if (!object) {
                                return_ACPI_STATUS (AE_NO_MEMORY);
                        }

                        object->integer.value = 0;
                        node->object = object;
                }

                /* Otherwise, return the error */

                else switch (opcode) {
                case AML_ARG_OP:

                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Uninitialized Arg[%d] at node %p\n",
                                index, node));

                        return_ACPI_STATUS (AE_AML_UNINITIALIZED_ARG);

                case AML_LOCAL_OP:

                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Uninitialized Local[%d] at node %p\n",
                                index, node));

                        return_ACPI_STATUS (AE_AML_UNINITIALIZED_LOCAL);

                default:
                        ACPI_REPORT_ERROR (("Not Arg/Local opcode: %X\n", opcode));
                        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:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument to delete
 *              walk_state          - Current walk state object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Delete the entry at Opcode:Index on the method stack.  Inserts
 *              a null into the stack slot after the object is deleted.
 *
 ******************************************************************************/

void
acpi_ds_method_data_delete_value (
        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_delete_value");


        /* 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_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:  Opcode              - Either AML_LOCAL_OP or AML_ARG_OP
 *              Index               - which local_var or argument 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 (
        u16                             opcode,
        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, "Opcode=%X Index=%d Obj=%p\n",
                opcode, 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 (opcode, 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 (opcode == AML_ARG_OP) {
                        /*
                         * Make sure that the object is the correct type.  This may be overkill, but
                         * it is here because references were NS nodes in the past.  Now they are
                         * operand objects of type Reference.
                         */
                        if (ACPI_GET_DESCRIPTOR_TYPE (current_obj_desc) != ACPI_DESC_TYPE_OPERAND) {
                                ACPI_REPORT_ERROR (("Invalid descriptor type while storing to method arg: [%s]\n",
                                                acpi_ut_get_descriptor_name (current_obj_desc)));
                                return_ACPI_STATUS (AE_AML_INTERNAL);
                        }

                        /*
                         * If we have a valid reference object that came from ref_of(), do the
                         * indirect store
                         */
                        if ((current_obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) &&
                                (current_obj_desc->reference.opcode == AML_REF_OF_OP)) {
                                ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
                                                "Arg (%p) is an obj_ref(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 (opcode, 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 (opcode, 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);
}