acpi_status acpi_ps_parse_aml()

in acpica/psparse.c [408:687]


acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
{
	acpi_status status;
	struct acpi_thread_state *thread;
	struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list;
	struct acpi_walk_state *previous_walk_state;

	ACPI_FUNCTION_TRACE(ps_parse_aml);

	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
			  "Entered with WalkState=%p Aml=%p size=%X\n",
			  walk_state, walk_state->parser_state.aml,
			  walk_state->parser_state.aml_size));

	if (!walk_state->parser_state.aml) {
		return_ACPI_STATUS(AE_BAD_ADDRESS);
	}

	/* Create and initialize a new thread state */

	thread = acpi_ut_create_thread_state();
	if (!thread) {
		if (walk_state->method_desc) {

			/* Executing a control method - additional cleanup */

			acpi_ds_terminate_control_method(walk_state->
							 method_desc,
							 walk_state);
		}

		acpi_ds_delete_walk_state(walk_state);
		return_ACPI_STATUS(AE_NO_MEMORY);
	}

	walk_state->thread = thread;

	/*
	 * If executing a method, the starting sync_level is this method's
	 * sync_level
	 */
	if (walk_state->method_desc) {
		walk_state->thread->current_sync_level =
		    walk_state->method_desc->method.sync_level;
	}

	acpi_ds_push_walk_state(walk_state, thread);

	/*
	 * This global allows the AML debugger to get a handle to the currently
	 * executing control method.
	 */
	acpi_gbl_current_walk_list = thread;

	/*
	 * Execute the walk loop as long as there is a valid Walk State. This
	 * handles nested control method invocations without recursion.
	 */
	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));

	status = AE_OK;
	while (walk_state) {
		if (ACPI_SUCCESS(status)) {
			/*
			 * The parse_loop executes AML until the method terminates
			 * or calls another method.
			 */
			status = acpi_ps_parse_loop(walk_state);
		}

		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
				  "Completed one call to walk loop, %s State=%p\n",
				  acpi_format_exception(status), walk_state));

		if (walk_state->method_pathname && walk_state->method_is_nested) {

			/* Optional object evaluation log */

			ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
					      "%-26s:  %*s%s\n",
					      "   Exit nested method",
					      (walk_state->
					       method_nesting_depth + 1) * 3,
					      " ",
					      &walk_state->method_pathname[1]));

			ACPI_FREE(walk_state->method_pathname);
			walk_state->method_is_nested = FALSE;
		}
		if (status == AE_CTRL_TRANSFER) {
			/*
			 * A method call was detected.
			 * Transfer control to the called control method
			 */
			status =
			    acpi_ds_call_control_method(thread, walk_state,
							NULL);
			if (ACPI_FAILURE(status)) {
				status =
				    acpi_ds_method_error(status, walk_state);
			}

			/*
			 * If the transfer to the new method method call worked,
			 * a new walk state was created -- get it
			 */
			walk_state = acpi_ds_get_current_walk_state(thread);
			continue;
		} else if (status == AE_CTRL_TERMINATE) {
			status = AE_OK;
		} else if ((status != AE_OK) && (walk_state->method_desc)) {

			/* Either the method parse or actual execution failed */

			acpi_ex_exit_interpreter();
			if (status == AE_ABORT_METHOD) {
				acpi_ns_print_node_pathname(walk_state->
							    method_node,
							    "Aborting method");
				acpi_os_printf("\n");
			} else {
				ACPI_ERROR_METHOD("Aborting method",
						  walk_state->method_node, NULL,
						  status);
			}
			acpi_ex_enter_interpreter();

			/* Check for possible multi-thread reentrancy problem */

			if ((status == AE_ALREADY_EXISTS) &&
			    (!(walk_state->method_desc->method.info_flags &
			       ACPI_METHOD_SERIALIZED))) {
				/*
				 * Method is not serialized and tried to create an object
				 * twice. The probable cause is that the method cannot
				 * handle reentrancy. Mark as "pending serialized" now, and
				 * then mark "serialized" when the last thread exits.
				 */
				walk_state->method_desc->method.info_flags |=
				    ACPI_METHOD_SERIALIZED_PENDING;
			}
		}

		/* We are done with this walk, move on to the parent if any */

		walk_state = acpi_ds_pop_walk_state(thread);

		/* Reset the current scope to the beginning of scope stack */

		acpi_ds_scope_stack_clear(walk_state);

		/*
		 * If we just returned from the execution of a control method or if we
		 * encountered an error during the method parse phase, there's lots of
		 * cleanup to do
		 */
		if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
		     ACPI_PARSE_EXECUTE &&
		     !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) ||
		    (ACPI_FAILURE(status))) {
			acpi_ds_terminate_control_method(walk_state->
							 method_desc,
							 walk_state);
		}

		/* Delete this walk state and all linked control states */

		acpi_ps_cleanup_scope(&walk_state->parser_state);
		previous_walk_state = walk_state;

		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
				  "ReturnValue=%p, ImplicitValue=%p State=%p\n",
				  walk_state->return_desc,
				  walk_state->implicit_return_obj, walk_state));

		/* Check if we have restarted a preempted walk */

		walk_state = acpi_ds_get_current_walk_state(thread);
		if (walk_state) {
			if (ACPI_SUCCESS(status)) {
				/*
				 * There is another walk state, restart it.
				 * If the method return value is not used by the parent,
				 * The object is deleted
				 */
				if (!previous_walk_state->return_desc) {
					/*
					 * In slack mode execution, if there is no return value
					 * we should implicitly return zero (0) as a default value.
					 */
					if (acpi_gbl_enable_interpreter_slack &&
					    !previous_walk_state->
					    implicit_return_obj) {
						previous_walk_state->
						    implicit_return_obj =
						    acpi_ut_create_integer_object
						    ((u64) 0);
						if (!previous_walk_state->
						    implicit_return_obj) {
							return_ACPI_STATUS
							    (AE_NO_MEMORY);
						}
					}

					/* Restart the calling control method */

					status =
					    acpi_ds_restart_control_method
					    (walk_state,
					     previous_walk_state->
					     implicit_return_obj);
				} else {
					/*
					 * We have a valid return value, delete any implicit
					 * return value.
					 */
					acpi_ds_clear_implicit_return
					    (previous_walk_state);

					status =
					    acpi_ds_restart_control_method
					    (walk_state,
					     previous_walk_state->return_desc);
				}
				if (ACPI_SUCCESS(status)) {
					walk_state->walk_type |=
					    ACPI_WALK_METHOD_RESTART;
				}
			} else {
				/* On error, delete any return object or implicit return */

				acpi_ut_remove_reference(previous_walk_state->
							 return_desc);
				acpi_ds_clear_implicit_return
				    (previous_walk_state);
			}
		}

		/*
		 * Just completed a 1st-level method, save the final internal return
		 * value (if any)
		 */
		else if (previous_walk_state->caller_return_desc) {
			if (previous_walk_state->implicit_return_obj) {
				*(previous_walk_state->caller_return_desc) =
				    previous_walk_state->implicit_return_obj;
			} else {
				/* NULL if no return value */

				*(previous_walk_state->caller_return_desc) =
				    previous_walk_state->return_desc;
			}
		} else {
			if (previous_walk_state->return_desc) {

				/* Caller doesn't want it, must delete it */

				acpi_ut_remove_reference(previous_walk_state->
							 return_desc);
			}
			if (previous_walk_state->implicit_return_obj) {

				/* Caller doesn't want it, must delete it */

				acpi_ut_remove_reference(previous_walk_state->
							 implicit_return_obj);
			}
		}

		acpi_ds_delete_walk_state(previous_walk_state);
	}

	/* Normal exit */

	acpi_ex_release_all_mutexes(thread);
	acpi_ut_delete_generic_state(ACPI_CAST_PTR
				     (union acpi_generic_state, thread));
	acpi_gbl_current_walk_list = prev_walk_list;
	return_ACPI_STATUS(status);
}