linux/drivers/acpi/dispatcher/dswexec.c

/******************************************************************************
 *
 * Module Name: dswexec - Dispatcher method execution callbacks;
 *                        dispatch to interpreter.
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2006, 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/acparser.h>
#include <acpi/amlcode.h>
#include <acpi/acdispat.h>
#include <acpi/acinterp.h>
#include <acpi/acnamesp.h>
#include <acpi/acdebug.h>

#define _COMPONENT          ACPI_DISPATCHER
ACPI_MODULE_NAME("dswexec")

/*
 * Dispatch table for opcode classes
 */
static ACPI_EXECUTE_OP acpi_gbl_op_type_dispatch[] = {
	acpi_ex_opcode_0A_0T_1R,
	acpi_ex_opcode_1A_0T_0R,
	acpi_ex_opcode_1A_0T_1R,
	acpi_ex_opcode_1A_1T_0R,
	acpi_ex_opcode_1A_1T_1R,
	acpi_ex_opcode_2A_0T_0R,
	acpi_ex_opcode_2A_0T_1R,
	acpi_ex_opcode_2A_1T_1R,
	acpi_ex_opcode_2A_2T_1R,
	acpi_ex_opcode_3A_0T_0R,
	acpi_ex_opcode_3A_1T_1R,
	acpi_ex_opcode_6A_0T_1R
};

/*****************************************************************************
 *
 * FUNCTION:    acpi_ds_get_predicate_value
 *
 * PARAMETERS:  walk_state      - Current state of the parse tree walk
 *              result_obj      - if non-zero, pop result from result stack
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Get the result of a predicate evaluation
 *
 ****************************************************************************/

acpi_status
acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
			    union acpi_operand_object *result_obj)
{
	acpi_status status = AE_OK;
	union acpi_operand_object *obj_desc;
	union acpi_operand_object *local_obj_desc = NULL;

	ACPI_FUNCTION_TRACE_PTR(ds_get_predicate_value, walk_state);

	walk_state->control_state->common.state = 0;

	if (result_obj) {
		status = acpi_ds_result_pop(&obj_desc, walk_state);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Could not get result from predicate evaluation"));

			return_ACPI_STATUS(status);
		}
	} else {
		status = acpi_ds_create_operand(walk_state, walk_state->op, 0);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

		status =
		    acpi_ex_resolve_to_value(&walk_state->operands[0],
					     walk_state);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

		obj_desc = walk_state->operands[0];
	}

	if (!obj_desc) {
		ACPI_ERROR((AE_INFO,
			    "No predicate ObjDesc=%p State=%p",
			    obj_desc, walk_state));

		return_ACPI_STATUS(AE_AML_NO_OPERAND);
	}

	/*
	 * Result of predicate evaluation must be an Integer
	 * object. Implicitly convert the argument if necessary.
	 */
	status = acpi_ex_convert_to_integer(obj_desc, &local_obj_desc, 16);
	if (ACPI_FAILURE(status)) {
		goto cleanup;
	}

	if (ACPI_GET_OBJECT_TYPE(local_obj_desc) != ACPI_TYPE_INTEGER) {
		ACPI_ERROR((AE_INFO,
			    "Bad predicate (not an integer) ObjDesc=%p State=%p Type=%X",
			    obj_desc, walk_state,
			    ACPI_GET_OBJECT_TYPE(obj_desc)));

		status = AE_AML_OPERAND_TYPE;
		goto cleanup;
	}

	/* Truncate the predicate to 32-bits if necessary */

	acpi_ex_truncate_for32bit_table(local_obj_desc);

	/*
	 * Save the result of the predicate evaluation on
	 * the control stack
	 */
	if (local_obj_desc->integer.value) {
		walk_state->control_state->common.value = TRUE;
	} else {
		/*
		 * Predicate is FALSE, we will just toss the
		 * rest of the package
		 */
		walk_state->control_state->common.value = FALSE;
		status = AE_CTRL_FALSE;
	}

      cleanup:

	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Completed a predicate eval=%X Op=%p\n",
			  walk_state->control_state->common.value,
			  walk_state->op));

	/* Break to debugger to display result */

	ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
			   (local_obj_desc, walk_state));

	/*
	 * Delete the predicate result object (we know that
	 * we don't need it anymore)
	 */
	if (local_obj_desc != obj_desc) {
		acpi_ut_remove_reference(local_obj_desc);
	}
	acpi_ut_remove_reference(obj_desc);

	walk_state->control_state->common.state = ACPI_CONTROL_NORMAL;
	return_ACPI_STATUS(status);
}

/*****************************************************************************
 *
 * FUNCTION:    acpi_ds_exec_begin_op
 *
 * PARAMETERS:  walk_state      - Current state of the parse tree walk
 *              out_op          - Where to return op if a new one is created
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Descending callback used during the execution of control
 *              methods.  This is where most operators and operands are
 *              dispatched to the interpreter.
 *
 ****************************************************************************/

acpi_status
acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
		      union acpi_parse_object **out_op)
{
	union acpi_parse_object *op;
	acpi_status status = AE_OK;
	u32 opcode_class;

	ACPI_FUNCTION_TRACE_PTR(ds_exec_begin_op, walk_state);

	op = walk_state->op;
	if (!op) {
		status = acpi_ds_load2_begin_op(walk_state, out_op);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

		op = *out_op;
		walk_state->op = op;
		walk_state->opcode = op->common.aml_opcode;
		walk_state->op_info =
		    acpi_ps_get_opcode_info(op->common.aml_opcode);

		if (acpi_ns_opens_scope(walk_state->op_info->object_type)) {
			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
					  "(%s) Popping scope for Op %p\n",
					  acpi_ut_get_type_name(walk_state->
								op_info->
								object_type),
					  op));

			status = acpi_ds_scope_stack_pop(walk_state);
			if (ACPI_FAILURE(status)) {
				return_ACPI_STATUS(status);
			}
		}
	}

	if (op == walk_state->origin) {
		if (out_op) {
			*out_op = op;
		}

		return_ACPI_STATUS(AE_OK);
	}

	/*
	 * If the previous opcode was a conditional, this opcode
	 * must be the beginning of the associated predicate.
	 * Save this knowledge in the current scope descriptor
	 */
	if ((walk_state->control_state) &&
	    (walk_state->control_state->common.state ==
	     ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
				  "Exec predicate Op=%p State=%p\n", op,
				  walk_state));

		walk_state->control_state->common.state =
		    ACPI_CONTROL_PREDICATE_EXECUTING;

		/* Save start of predicate */

		walk_state->control_state->control.predicate_op = op;
	}

	opcode_class = walk_state->op_info->class;

	/* We want to send namepaths to the load code */

	if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
		opcode_class = AML_CLASS_NAMED_OBJECT;
	}

	/*
	 * Handle the opcode based upon the opcode type
	 */
	switch (opcode_class) {
	case AML_CLASS_CONTROL:

		status = acpi_ds_result_stack_push(walk_state);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

		status = acpi_ds_exec_begin_control_op(walk_state, op);
		break;

	case AML_CLASS_NAMED_OBJECT:

		if (walk_state->walk_type == ACPI_WALK_METHOD) {
			/*
			 * Found a named object declaration during method execution;
			 * we must enter this object into the namespace.  The created
			 * object is temporary and will be deleted upon completion of
			 * the execution of this method.
			 */
			status = acpi_ds_load2_begin_op(walk_state, NULL);
		}

		if (op->common.aml_opcode == AML_REGION_OP) {
			status = acpi_ds_result_stack_push(walk_state);
		}
		break;

	case AML_CLASS_EXECUTE:
	case AML_CLASS_CREATE:
		/*
		 * Most operators with arguments.
		 * Start a new result/operand state
		 */
		if (walk_state->opcode != AML_CREATE_FIELD_OP) {
			status = acpi_ds_result_stack_push(walk_state);
		}
		break;

	default:
		break;
	}

	/* Nothing to do here during method execution */

	return_ACPI_STATUS(status);
}

/*****************************************************************************
 *
 * FUNCTION:    acpi_ds_exec_end_op
 *
 * PARAMETERS:  walk_state      - Current state of the parse tree walk
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Ascending callback used during the execution of control
 *              methods.  The only thing we really need to do here is to
 *              notice the beginning of IF, ELSE, and WHILE blocks.
 *
 ****************************************************************************/

acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
{
	union acpi_parse_object *op;
	acpi_status status = AE_OK;
	u32 op_type;
	u32 op_class;
	union acpi_parse_object *next_op;
	union acpi_parse_object *first_arg;

	ACPI_FUNCTION_TRACE_PTR(ds_exec_end_op, walk_state);

	op = walk_state->op;
	op_type = walk_state->op_info->type;
	op_class = walk_state->op_info->class;

	if (op_class == AML_CLASS_UNKNOWN) {
		ACPI_ERROR((AE_INFO, "Unknown opcode %X",
			    op->common.aml_opcode));
		return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
	}

	first_arg = op->common.value.arg;

	/* Init the walk state */

	walk_state->num_operands = 0;
	walk_state->return_desc = NULL;
	walk_state->result_obj = NULL;

	/* Call debugger for single step support (DEBUG build only) */

	ACPI_DEBUGGER_EXEC(status =
			   acpi_db_single_step(walk_state, op, op_class));
	ACPI_DEBUGGER_EXEC(if (ACPI_FAILURE(status)) {
			   return_ACPI_STATUS(status);}
	) ;

	/* Decode the Opcode Class */

	switch (op_class) {
	case AML_CLASS_ARGUMENT:	/* constants, literals, etc. - do nothing */
		break;

	case AML_CLASS_EXECUTE:	/* most operators with arguments */

		/* Build resolved operand stack */

		status = acpi_ds_create_operands(walk_state, first_arg);
		if (ACPI_FAILURE(status)) {
			goto cleanup;
		}

		/* Done with this result state (Now that operand stack is built) */

		status = acpi_ds_result_stack_pop(walk_state);
		if (ACPI_FAILURE(status)) {
			goto cleanup;
		}

		/*
		 * All opcodes require operand resolution, with the only exceptions
		 * being the object_type and size_of operators.
		 */
		if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE)) {

			/* Resolve all operands */

			status = acpi_ex_resolve_operands(walk_state->opcode,
							  &(walk_state->
							    operands
							    [walk_state->
							     num_operands - 1]),
							  walk_state);
			if (ACPI_SUCCESS(status)) {
				ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
						   ACPI_IMODE_EXECUTE,
						   acpi_ps_get_opcode_name
						   (walk_state->opcode),
						   walk_state->num_operands,
						   "after ExResolveOperands");
			}
		}

		if (ACPI_SUCCESS(status)) {
			/*
			 * Dispatch the request to the appropriate interpreter handler
			 * routine.  There is one routine per opcode "type" based upon the
			 * number of opcode arguments and return type.
			 */
			status =
			    acpi_gbl_op_type_dispatch[op_type] (walk_state);
		} else {
			/*
			 * Treat constructs of the form "Store(LocalX,LocalX)" as noops when the
			 * Local is uninitialized.
			 */
			if ((status == AE_AML_UNINITIALIZED_LOCAL) &&
			    (walk_state->opcode == AML_STORE_OP) &&
			    (walk_state->operands[0]->common.type ==
			     ACPI_TYPE_LOCAL_REFERENCE)
			    && (walk_state->operands[1]->common.type ==
				ACPI_TYPE_LOCAL_REFERENCE)
			    && (walk_state->operands[0]->reference.opcode ==
				walk_state->operands[1]->reference.opcode)
			    && (walk_state->operands[0]->reference.offset ==
				walk_state->operands[1]->reference.offset)) {
				status = AE_OK;
			} else {
				ACPI_EXCEPTION((AE_INFO, status,
						"While resolving operands for [%s]",
						acpi_ps_get_opcode_name
						(walk_state->opcode)));
			}
		}

		/* Always delete the argument objects and clear the operand stack */

		acpi_ds_clear_operands(walk_state);

		/*
		 * If a result object was returned from above, push it on the
		 * current result stack
		 */
		if (ACPI_SUCCESS(status) && walk_state->result_obj) {
			status =
			    acpi_ds_result_push(walk_state->result_obj,
						walk_state);
		}

		break;

	default:

		switch (op_type) {
		case AML_TYPE_CONTROL:	/* Type 1 opcode, IF/ELSE/WHILE/NOOP */

			/* 1 Operand, 0 external_result, 0 internal_result */

			status = acpi_ds_exec_end_control_op(walk_state, op);

			/* Make sure to properly pop the result stack */

			if (ACPI_SUCCESS(status)) {
				status = acpi_ds_result_stack_pop(walk_state);
			} else if (status == AE_CTRL_PENDING) {
				status = acpi_ds_result_stack_pop(walk_state);
				if (ACPI_SUCCESS(status)) {
					status = AE_CTRL_PENDING;
				}
			}
			break;

		case AML_TYPE_METHOD_CALL:

			/*
			 * If the method is referenced from within a package
			 * declaration, it is not a invocation of the method, just
			 * a reference to it.
			 */
			if ((op->asl.parent) &&
			    ((op->asl.parent->asl.aml_opcode == AML_PACKAGE_OP)
			     || (op->asl.parent->asl.aml_opcode ==
				 AML_VAR_PACKAGE_OP))) {
				ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
						  "Method Reference in a Package, Op=%p\n",
						  op));
				op->common.node =
				    (struct acpi_namespace_node *)op->asl.value.
				    arg->asl.node->object;
				acpi_ut_add_reference(op->asl.value.arg->asl.
						      node->object);
				return_ACPI_STATUS(AE_OK);
			}

			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
					  "Method invocation, Op=%p\n", op));

			/*
			 * (AML_METHODCALL) Op->Asl.Value.Arg->Asl.Node contains
			 * the method Node pointer
			 */
			/* next_op points to the op that holds the method name */

			next_op = first_arg;

			/* next_op points to first argument op */

			next_op = next_op->common.next;

			/*
			 * Get the method's arguments and put them on the operand stack
			 */
			status = acpi_ds_create_operands(walk_state, next_op);
			if (ACPI_FAILURE(status)) {
				break;
			}

			/*
			 * Since the operands will be passed to another control method,
			 * we must resolve all local references here (Local variables,
			 * arguments to *this* method, etc.)
			 */
			status = acpi_ds_resolve_operands(walk_state);
			if (ACPI_FAILURE(status)) {

				/* On error, clear all resolved operands */

				acpi_ds_clear_operands(walk_state);
				break;
			}

			/*
			 * Tell the walk loop to preempt this running method and
			 * execute the new method
			 */
			status = AE_CTRL_TRANSFER;

			/*
			 * Return now; we don't want to disturb anything,
			 * especially the operand count!
			 */
			return_ACPI_STATUS(status);

		case AML_TYPE_CREATE_FIELD:

			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
					  "Executing CreateField Buffer/Index Op=%p\n",
					  op));

			status = acpi_ds_load2_end_op(walk_state);
			if (ACPI_FAILURE(status)) {
				break;
			}

			status =
			    acpi_ds_eval_buffer_field_operands(walk_state, op);
			break;

		case AML_TYPE_CREATE_OBJECT:

			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
					  "Executing CreateObject (Buffer/Package) Op=%p\n",
					  op));

			switch (op->common.parent->common.aml_opcode) {
			case AML_NAME_OP:

				/*
				 * Put the Node on the object stack (Contains the ACPI Name
				 * of this object)
				 */
				walk_state->operands[0] =
				    (void *)op->common.parent->common.node;
				walk_state->num_operands = 1;

				status = acpi_ds_create_node(walk_state,
							     op->common.parent->
							     common.node,
							     op->common.parent);
				if (ACPI_FAILURE(status)) {
					break;
				}

				/* Fall through */
				/*lint -fallthrough */

			case AML_INT_EVAL_SUBTREE_OP:

				status =
				    acpi_ds_eval_data_object_operands
				    (walk_state, op,
				     acpi_ns_get_attached_object(op->common.
								 parent->common.
								 node));
				break;

			default:

				status =
				    acpi_ds_eval_data_object_operands
				    (walk_state, op, NULL);
				break;
			}

			/* Done with result state (Now that operand stack is built) */

			status = acpi_ds_result_stack_pop(walk_state);
			if (ACPI_FAILURE(status)) {
				goto cleanup;
			}

			/*
			 * If a result object was returned from above, push it on the
			 * current result stack
			 */
			if (walk_state->result_obj) {
				status =
				    acpi_ds_result_push(walk_state->result_obj,
							walk_state);
			}
			break;

		case AML_TYPE_NAMED_FIELD:
		case AML_TYPE_NAMED_COMPLEX:
		case AML_TYPE_NAMED_SIMPLE:
		case AML_TYPE_NAMED_NO_OBJ:

			status = acpi_ds_load2_end_op(walk_state);
			if (ACPI_FAILURE(status)) {
				break;
			}

			if (op->common.aml_opcode == AML_REGION_OP) {
				ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
						  "Executing OpRegion Address/Length Op=%p\n",
						  op));

				status =
				    acpi_ds_eval_region_operands(walk_state,
								 op);
				if (ACPI_FAILURE(status)) {
					break;
				}

				status = acpi_ds_result_stack_pop(walk_state);
			}

			break;

		case AML_TYPE_UNDEFINED:

			ACPI_ERROR((AE_INFO,
				    "Undefined opcode type Op=%p", op));
			return_ACPI_STATUS(AE_NOT_IMPLEMENTED);

		case AML_TYPE_BOGUS:

			ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
					  "Internal opcode=%X type Op=%p\n",
					  walk_state->opcode, op));
			break;

		default:

			ACPI_ERROR((AE_INFO,
				    "Unimplemented opcode, class=%X type=%X Opcode=%X Op=%p",
				    op_class, op_type, op->common.aml_opcode,
				    op));

			status = AE_NOT_IMPLEMENTED;
			break;
		}
	}

	/*
	 * ACPI 2.0 support for 64-bit integers: Truncate numeric
	 * result value if we are executing from a 32-bit ACPI table
	 */
	acpi_ex_truncate_for32bit_table(walk_state->result_obj);

	/*
	 * Check if we just completed the evaluation of a
	 * conditional predicate
	 */

	if ((ACPI_SUCCESS(status)) &&
	    (walk_state->control_state) &&
	    (walk_state->control_state->common.state ==
	     ACPI_CONTROL_PREDICATE_EXECUTING) &&
	    (walk_state->control_state->control.predicate_op == op)) {
		status =
		    acpi_ds_get_predicate_value(walk_state,
						walk_state->result_obj);
		walk_state->result_obj = NULL;
	}

      cleanup:

	if (walk_state->result_obj) {

		/* Break to debugger to display result */

		ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
				   (walk_state->result_obj, walk_state));

		/*
		 * Delete the result op if and only if:
		 * Parent will not use the result -- such as any
		 * non-nested type2 op in a method (parent will be method)
		 */
		acpi_ds_delete_result_if_not_used(op, walk_state->result_obj,
						  walk_state);
	}
#ifdef _UNDER_DEVELOPMENT

	if (walk_state->parser_state.aml == walk_state->parser_state.aml_end) {
		acpi_db_method_end(walk_state);
	}
#endif

	/* Invoke exception handler on error */

	if (ACPI_FAILURE(status)) {
		status = acpi_ds_method_error(status, walk_state);
	}

	/* Always clear the object stack */

	walk_state->num_operands = 0;
	return_ACPI_STATUS(status);
}