dswstate.c

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/******************************************************************************
 *
 * Module Name: dswstate - Dispatcher parse tree walk management routines
 *
 *****************************************************************************/

/*
 * 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 "acparser.h"
#include "acdispat.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_DISPATCHER
ACPI_MODULE_NAME("dswstate")

  /* Local prototypes */
static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *ws);
static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *ws);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_result_pop
 *
 * PARAMETERS:  object              - Where to return the popped object
 *              walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off the top of this walk's result stack
 *
 ******************************************************************************/

acpi_status
acpi_ds_result_pop(union acpi_operand_object **object,
           struct acpi_walk_state *walk_state)
{
    u32 index;
    union acpi_generic_state *state;
    acpi_status status;

    ACPI_FUNCTION_NAME(ds_result_pop);

    state = walk_state->results;

    /* Incorrect state of result stack */

    if (state && !walk_state->result_count) {
        ACPI_ERROR((AE_INFO, "No results on result stack"));
        return (AE_AML_INTERNAL);
    }

    if (!state && walk_state->result_count) {
        ACPI_ERROR((AE_INFO, "No result state for result stack"));
        return (AE_AML_INTERNAL);
    }

    /* Empty result stack */

    if (!state) {
        ACPI_ERROR((AE_INFO, "Result stack is empty! State=%p",
                walk_state));
        return (AE_AML_NO_RETURN_VALUE);
    }

    /* Return object of the top element and clean that top element result stack */

    walk_state->result_count--;
    index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;

    *object = state->results.obj_desc[index];
    if (!*object) {
        ACPI_ERROR((AE_INFO,
                "No result objects on result stack, State=%p",
                walk_state));
        return (AE_AML_NO_RETURN_VALUE);
    }

    state->results.obj_desc[index] = NULL;
    if (index == 0) {
        status = acpi_ds_result_stack_pop(walk_state);
        if (ACPI_FAILURE(status)) {
            return (status);
        }
    }

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
              "Obj=%p [%s] Index=%X State=%p Num=%X\n", *object,
              acpi_ut_get_object_type_name(*object),
              index, walk_state, walk_state->result_count));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_result_push
 *
 * PARAMETERS:  object              - Where to return the popped object
 *              walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push an object onto the current result stack
 *
 ******************************************************************************/

acpi_status
acpi_ds_result_push(union acpi_operand_object * object,
            struct acpi_walk_state * walk_state)
{
    union acpi_generic_state *state;
    acpi_status status;
    u32 index;

    ACPI_FUNCTION_NAME(ds_result_push);

    if (walk_state->result_count > walk_state->result_size) {
        ACPI_ERROR((AE_INFO, "Result stack is full"));
        return (AE_AML_INTERNAL);
    } else if (walk_state->result_count == walk_state->result_size) {

        /* Extend the result stack */

        status = acpi_ds_result_stack_push(walk_state);
        if (ACPI_FAILURE(status)) {
            ACPI_ERROR((AE_INFO,
                    "Failed to extend the result stack"));
            return (status);
        }
    }

    if (!(walk_state->result_count < walk_state->result_size)) {
        ACPI_ERROR((AE_INFO, "No free elements in result stack"));
        return (AE_AML_INTERNAL);
    }

    state = walk_state->results;
    if (!state) {
        ACPI_ERROR((AE_INFO, "No result stack frame during push"));
        return (AE_AML_INTERNAL);
    }

    if (!object) {
        ACPI_ERROR((AE_INFO,
                "Null Object! Obj=%p State=%p Num=%u",
                object, walk_state, walk_state->result_count));
        return (AE_BAD_PARAMETER);
    }

    /* Assign the address of object to the top free element of result stack */

    index = (u32)walk_state->result_count % ACPI_RESULTS_FRAME_OBJ_NUM;
    state->results.obj_desc[index] = object;
    walk_state->result_count++;

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p Num=%X Cur=%X\n",
              object,
              acpi_ut_get_object_type_name((union
                            acpi_operand_object *)
                               object), walk_state,
              walk_state->result_count,
              walk_state->current_result));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_result_stack_push
 *
 * PARAMETERS:  walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push an object onto the walk_state result stack
 *
 ******************************************************************************/

static acpi_status acpi_ds_result_stack_push(struct acpi_walk_state *walk_state)
{
    union acpi_generic_state *state;

    ACPI_FUNCTION_NAME(ds_result_stack_push);

    /* Check for stack overflow */

    if (((u32) walk_state->result_size + ACPI_RESULTS_FRAME_OBJ_NUM) >
        ACPI_RESULTS_OBJ_NUM_MAX) {
        ACPI_ERROR((AE_INFO, "Result stack overflow: State=%p Num=%u",
                walk_state, walk_state->result_size));
        return (AE_STACK_OVERFLOW);
    }

    state = acpi_ut_create_generic_state();
    if (!state) {
        return (AE_NO_MEMORY);
    }

    state->common.descriptor_type = ACPI_DESC_TYPE_STATE_RESULT;
    acpi_ut_push_generic_state(&walk_state->results, state);

    /* Increase the length of the result stack by the length of frame */

    walk_state->result_size += ACPI_RESULTS_FRAME_OBJ_NUM;

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Results=%p State=%p\n",
              state, walk_state));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_result_stack_pop
 *
 * PARAMETERS:  walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop an object off of the walk_state result stack
 *
 ******************************************************************************/

static acpi_status acpi_ds_result_stack_pop(struct acpi_walk_state *walk_state)
{
    union acpi_generic_state *state;

    ACPI_FUNCTION_NAME(ds_result_stack_pop);

    /* Check for stack underflow */

    if (walk_state->results == NULL) {
        ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
                  "Result stack underflow - State=%p\n",
                  walk_state));
        return (AE_AML_NO_OPERAND);
    }

    if (walk_state->result_size < ACPI_RESULTS_FRAME_OBJ_NUM) {
        ACPI_ERROR((AE_INFO, "Insufficient result stack size"));
        return (AE_AML_INTERNAL);
    }

    state = acpi_ut_pop_generic_state(&walk_state->results);
    acpi_ut_delete_generic_state(state);

    /* Decrease the length of result stack by the length of frame */

    walk_state->result_size -= ACPI_RESULTS_FRAME_OBJ_NUM;

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
              "Result=%p RemainingResults=%X State=%p\n",
              state, walk_state->result_count, walk_state));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_obj_stack_push
 *
 * PARAMETERS:  object              - Object to push
 *              walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push an object onto this walk's object/operand stack
 *
 ******************************************************************************/

acpi_status
acpi_ds_obj_stack_push(void *object, struct acpi_walk_state * walk_state)
{
    ACPI_FUNCTION_NAME(ds_obj_stack_push);

    /* Check for stack overflow */

    if (walk_state->num_operands >= ACPI_OBJ_NUM_OPERANDS) {
        ACPI_ERROR((AE_INFO,
                "Object stack overflow! Obj=%p State=%p #Ops=%u",
                object, walk_state, walk_state->num_operands));
        return (AE_STACK_OVERFLOW);
    }

    /* Put the object onto the stack */

    walk_state->operands[walk_state->operand_index] = object;
    walk_state->num_operands++;

    /* For the usual order of filling the operand stack */

    walk_state->operand_index++;

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Obj=%p [%s] State=%p #Ops=%X\n",
              object,
              acpi_ut_get_object_type_name((union
                            acpi_operand_object *)
                               object), walk_state,
              walk_state->num_operands));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_obj_stack_pop
 *
 * PARAMETERS:  pop_count           - Number of objects/entries to pop
 *              walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop this walk's object stack.  Objects on the stack are NOT
 *              deleted by this routine.
 *
 ******************************************************************************/

acpi_status
acpi_ds_obj_stack_pop(u32 pop_count, struct acpi_walk_state * walk_state)
{
    u32 i;

    ACPI_FUNCTION_NAME(ds_obj_stack_pop);

    for (i = 0; i < pop_count; i++) {

        /* Check for stack underflow */

        if (walk_state->num_operands == 0) {
            ACPI_ERROR((AE_INFO,
                    "Object stack underflow! Count=%X State=%p #Ops=%u",
                    pop_count, walk_state,
                    walk_state->num_operands));
            return (AE_STACK_UNDERFLOW);
        }

        /* Just set the stack entry to null */

        walk_state->num_operands--;
        walk_state->operands[walk_state->num_operands] = NULL;
    }

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%u\n",
              pop_count, walk_state, walk_state->num_operands));

    return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_obj_stack_pop_and_delete
 *
 * PARAMETERS:  pop_count           - Number of objects/entries to pop
 *              walk_state          - Current Walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop this walk's object stack and delete each object that is
 *              popped off.
 *
 ******************************************************************************/

void
acpi_ds_obj_stack_pop_and_delete(u32 pop_count,
                 struct acpi_walk_state *walk_state)
{
    s32 i;
    union acpi_operand_object *obj_desc;

    ACPI_FUNCTION_NAME(ds_obj_stack_pop_and_delete);

    if (pop_count == 0) {
        return;
    }

    for (i = (s32) pop_count - 1; i >= 0; i--) {
        if (walk_state->num_operands == 0) {
            return;
        }

        /* Pop the stack and delete an object if present in this stack entry */

        walk_state->num_operands--;
        obj_desc = walk_state->operands[i];
        if (obj_desc) {
            acpi_ut_remove_reference(walk_state->operands[i]);
            walk_state->operands[i] = NULL;
        }
    }

    ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Count=%X State=%p #Ops=%X\n",
              pop_count, walk_state, walk_state->num_operands));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_get_current_walk_state
 *
 * PARAMETERS:  thread          - Get current active state for this Thread
 *
 * RETURN:      Pointer to the current walk state
 *
 * DESCRIPTION: Get the walk state that is at the head of the list (the "current"
 *              walk state.)
 *
 ******************************************************************************/

struct acpi_walk_state *acpi_ds_get_current_walk_state(struct acpi_thread_state
                               *thread)
{
    ACPI_FUNCTION_NAME(ds_get_current_walk_state);

    if (!thread) {
        return (NULL);
    }

    ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Current WalkState %p\n",
              thread->walk_state_list));

    return (thread->walk_state_list);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_push_walk_state
 *
 * PARAMETERS:  walk_state      - State to push
 *              thread          - Thread state object
 *
 * RETURN:      None
 *
 * DESCRIPTION: Place the Thread state at the head of the state list
 *
 ******************************************************************************/

void
acpi_ds_push_walk_state(struct acpi_walk_state *walk_state,
            struct acpi_thread_state *thread)
{
    ACPI_FUNCTION_TRACE(ds_push_walk_state);

    walk_state->next = thread->walk_state_list;
    thread->walk_state_list = walk_state;

    return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_pop_walk_state
 *
 * PARAMETERS:  thread      - Current thread state
 *
 * RETURN:      A walk_state object popped from the thread's stack
 *
 * DESCRIPTION: Remove and return the walkstate object that is at the head of
 *              the walk stack for the given walk list.  NULL indicates that
 *              the list is empty.
 *
 ******************************************************************************/

struct acpi_walk_state *acpi_ds_pop_walk_state(struct acpi_thread_state *thread)
{
    struct acpi_walk_state *walk_state;

    ACPI_FUNCTION_TRACE(ds_pop_walk_state);

    walk_state = thread->walk_state_list;

    if (walk_state) {

        /* Next walk state becomes the current walk state */

        thread->walk_state_list = walk_state->next;

        /*
         * Don't clear the NEXT field, this serves as an indicator
         * that there is a parent WALK STATE
         * Do Not: walk_state->Next = NULL;
         */
    }

    return_PTR(walk_state);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_create_walk_state
 *
 * PARAMETERS:  owner_id        - ID for object creation
 *              origin          - Starting point for this walk
 *              method_desc     - Method object
 *              thread          - Current thread state
 *
 * RETURN:      Pointer to the new walk state.
 *
 * DESCRIPTION: Allocate and initialize a new walk state.  The current walk
 *              state is set to this new state.
 *
 ******************************************************************************/

struct acpi_walk_state *acpi_ds_create_walk_state(acpi_owner_id owner_id, union acpi_parse_object
                          *origin, union acpi_operand_object
                          *method_desc, struct acpi_thread_state
                          *thread)
{
    struct acpi_walk_state *walk_state;

    ACPI_FUNCTION_TRACE(ds_create_walk_state);

    walk_state = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_walk_state));
    if (!walk_state) {
        return_PTR(NULL);
    }

    walk_state->descriptor_type = ACPI_DESC_TYPE_WALK;
    walk_state->method_desc = method_desc;
    walk_state->owner_id = owner_id;
    walk_state->origin = origin;
    walk_state->thread = thread;

    walk_state->parser_state.start_op = origin;

    /* Init the method args/local */

#if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
    acpi_ds_method_data_init(walk_state);
#endif

    /* Put the new state at the head of the walk list */

    if (thread) {
        acpi_ds_push_walk_state(walk_state, thread);
    }

    return_PTR(walk_state);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_init_aml_walk
 *
 * PARAMETERS:  walk_state      - New state to be initialized
 *              op              - Current parse op
 *              method_node     - Control method NS node, if any
 *              aml_start       - Start of AML
 *              aml_length      - Length of AML
 *              info            - Method info block (params, etc.)
 *              pass_number     - 1, 2, or 3
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize a walk state for a pass 1 or 2 parse tree walk
 *
 ******************************************************************************/

acpi_status
acpi_ds_init_aml_walk(struct acpi_walk_state *walk_state,
              union acpi_parse_object *op,
              struct acpi_namespace_node *method_node,
              u8 * aml_start,
              u32 aml_length,
              struct acpi_evaluate_info *info, u8 pass_number)
{
    acpi_status status;
    struct acpi_parse_state *parser_state = &walk_state->parser_state;
    union acpi_parse_object *extra_op;

    ACPI_FUNCTION_TRACE(ds_init_aml_walk);

    walk_state->parser_state.aml =
        walk_state->parser_state.aml_start = aml_start;
    walk_state->parser_state.aml_end =
        walk_state->parser_state.pkg_end = aml_start + aml_length;

    /* The next_op of the next_walk will be the beginning of the method */

    walk_state->next_op = NULL;
    walk_state->pass_number = pass_number;

    if (info) {
        walk_state->params = info->parameters;
        walk_state->caller_return_desc = &info->return_object;
    }

    status = acpi_ps_init_scope(&walk_state->parser_state, op);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    if (method_node) {
        walk_state->parser_state.start_node = method_node;
        walk_state->walk_type = ACPI_WALK_METHOD;
        walk_state->method_node = method_node;
        walk_state->method_desc =
            acpi_ns_get_attached_object(method_node);

        /* Push start scope on scope stack and make it current  */

        status =
            acpi_ds_scope_stack_push(method_node, ACPI_TYPE_METHOD,
                         walk_state);
        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }

        /* Init the method arguments */

        status = acpi_ds_method_data_init_args(walk_state->params,
                               ACPI_METHOD_NUM_ARGS,
                               walk_state);
        if (ACPI_FAILURE(status)) {
            return_ACPI_STATUS(status);
        }
    } else {
        /*
         * Setup the current scope.
         * Find a Named Op that has a namespace node associated with it.
         * search upwards from this Op.  Current scope is the first
         * Op with a namespace node.
         */
        extra_op = parser_state->start_op;
        while (extra_op && !extra_op->common.node) {
            extra_op = extra_op->common.parent;
        }

        if (!extra_op) {
            parser_state->start_node = NULL;
        } else {
            parser_state->start_node = extra_op->common.node;
        }

        if (parser_state->start_node) {

            /* Push start scope on scope stack and make it current  */

            status =
                acpi_ds_scope_stack_push(parser_state->start_node,
                             parser_state->start_node->
                             type, walk_state);
            if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
            }
        }
    }

    status = acpi_ds_init_callbacks(walk_state, pass_number);
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ds_delete_walk_state
 *
 * PARAMETERS:  walk_state      - State to delete
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Delete a walk state including all internal data structures
 *
 ******************************************************************************/

void acpi_ds_delete_walk_state(struct acpi_walk_state *walk_state)
{
    union acpi_generic_state *state;

    ACPI_FUNCTION_TRACE_PTR(ds_delete_walk_state, walk_state);

    if (!walk_state) {
        return;
    }

    if (walk_state->descriptor_type != ACPI_DESC_TYPE_WALK) {
        ACPI_ERROR((AE_INFO, "%p is not a valid walk state",
                walk_state));
        return;
    }

    /* There should not be any open scopes */

    if (walk_state->parser_state.scope) {
        ACPI_ERROR((AE_INFO, "%p walk still has a scope list",
                walk_state));
        acpi_ps_cleanup_scope(&walk_state->parser_state);
    }

    /* Always must free any linked control states */

    while (walk_state->control_state) {
        state = walk_state->control_state;
        walk_state->control_state = state->common.next;

        acpi_ut_delete_generic_state(state);
    }

    /* Always must free any linked parse states */

    while (walk_state->scope_info) {
        state = walk_state->scope_info;
        walk_state->scope_info = state->common.next;

        acpi_ut_delete_generic_state(state);
    }

    /* Always must free any stacked result states */

    while (walk_state->results) {
        state = walk_state->results;
        walk_state->results = state->common.next;

        acpi_ut_delete_generic_state(state);
    }

    ACPI_FREE(walk_state);
    return_VOID;
}