psparse.c

h内核

				 * Completed parsing an op_region declaration, we now
				 * know the length.
				 */
				op->named.length = (u32) (parser_state->aml - op->named.data);
			}
		}

		if (walk_state->op_info->flags & AML_CREATE) {
			/*
			 * Backup to beginning of create_xXXfield declaration (1 for
			 * Opcode)
			 *
			 * body_length is unknown until we parse the body
			 */
			op->named.length = (u32) (parser_state->aml - op->named.data);
		}

		/* This op complete, notify the dispatcher */

		if (walk_state->ascending_callback != NULL) {
			walk_state->op    = op;
			walk_state->opcode = op->common.aml_opcode;

			status = walk_state->ascending_callback (walk_state);
			status = acpi_ps_next_parse_state (walk_state, op, status);
			if (status == AE_CTRL_PENDING) {
				status = AE_OK;
				goto close_this_op;
			}
		}


close_this_op:
		/*
		 * Finished one argument of the containing scope
		 */
		parser_state->scope->parse_scope.arg_count--;

		/* Close this Op (will result in parse subtree deletion) */

		acpi_ps_complete_this_op (walk_state, op);
		op = NULL;
		if (pre_op) {
			acpi_ps_free_op (pre_op);
			pre_op = NULL;
		}

		switch (status) {
		case AE_OK:
			break;


		case AE_CTRL_TRANSFER:

			/*
			 * We are about to transfer to a called method.
			 */
			walk_state->prev_op = op;
			walk_state->prev_arg_types = walk_state->arg_types;
			return_ACPI_STATUS (status);


		case AE_CTRL_END:

			acpi_ps_pop_scope (parser_state, &op,
				&walk_state->arg_types, &walk_state->arg_count);

			if (op) {
				walk_state->op    = op;
				walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
				walk_state->opcode = op->common.aml_opcode;

				status = walk_state->ascending_callback (walk_state);
				status = acpi_ps_next_parse_state (walk_state, op, status);

				acpi_ps_complete_this_op (walk_state, op);
				op = NULL;
			}
			status = AE_OK;
			break;


		case AE_CTRL_BREAK:
		case AE_CTRL_CONTINUE:

			/* Pop off scopes until we find the While */

			while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
				acpi_ps_pop_scope (parser_state, &op,
					&walk_state->arg_types, &walk_state->arg_count);
			}

			/* Close this iteration of the While loop */

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

			status = walk_state->ascending_callback (walk_state);
			status = acpi_ps_next_parse_state (walk_state, op, status);

			acpi_ps_complete_this_op (walk_state, op);
			op = NULL;

			status = AE_OK;
			break;


		case AE_CTRL_TERMINATE:

			status = AE_OK;

			/* Clean up */
			do {
				if (op) {
					acpi_ps_complete_this_op (walk_state, op);
				}
				acpi_ps_pop_scope (parser_state, &op,
					&walk_state->arg_types, &walk_state->arg_count);

			} while (op);

			return_ACPI_STATUS (status);


		default:  /* All other non-AE_OK status */

			do {
				if (op) {
					acpi_ps_complete_this_op (walk_state, op);
				}
				acpi_ps_pop_scope (parser_state, &op,
					&walk_state->arg_types, &walk_state->arg_count);

			} while (op);


			/*
			 * TBD: Cleanup parse ops on error
			 */
#if 0
			if (op == NULL) {
				acpi_ps_pop_scope (parser_state, &op,
					&walk_state->arg_types, &walk_state->arg_count);
			}
#endif
			walk_state->prev_op = op;
			walk_state->prev_arg_types = walk_state->arg_types;
			return_ACPI_STATUS (status);
		}

		/* This scope complete? */

		if (acpi_ps_has_completed_scope (parser_state)) {
			acpi_ps_pop_scope (parser_state, &op,
				&walk_state->arg_types, &walk_state->arg_count);
			ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op));
		}
		else {
			op = NULL;
		}

	} /* while parser_state->Aml */


	/*
	 * Complete the last Op (if not completed), and clear the scope stack.
	 * It is easily possible to end an AML "package" with an unbounded number
	 * of open scopes (such as when several ASL blocks are closed with
	 * sequential closing braces).  We want to terminate each one cleanly.
	 */
	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "AML package complete at Op %p\n", op));
	do {
		if (op) {
			if (walk_state->ascending_callback != NULL) {
				walk_state->op    = op;
				walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
				walk_state->opcode = op->common.aml_opcode;

				status = walk_state->ascending_callback (walk_state);
				status = acpi_ps_next_parse_state (walk_state, op, status);
				if (status == AE_CTRL_PENDING) {
					status = AE_OK;
					goto close_this_op;
				}

				if (status == AE_CTRL_TERMINATE) {
					status = AE_OK;

					/* Clean up */
					do {
						if (op) {
							acpi_ps_complete_this_op (walk_state, op);
						}

						acpi_ps_pop_scope (parser_state, &op,
							&walk_state->arg_types, &walk_state->arg_count);

					} while (op);

					return_ACPI_STATUS (status);
				}

				else if (ACPI_FAILURE (status)) {
					acpi_ps_complete_this_op (walk_state, op);
					return_ACPI_STATUS (status);
				}
			}

			acpi_ps_complete_this_op (walk_state, op);
		}

		acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types,
			&walk_state->arg_count);

	} while (op);

	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ps_parse_aml
 *
 * PARAMETERS:  start_scope     - The starting point of the parse.  Becomes the
 *                                root of the parsed op tree.
 *              Aml             - Pointer to the raw AML code to parse
 *              aml_size        - Length of the AML to parse
 *
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Parse raw AML and return a tree of ops
 *
 ******************************************************************************/

acpi_status
acpi_ps_parse_aml (
	struct acpi_walk_state          *walk_state)
{
	acpi_status                     status;
	acpi_status                     terminate_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 walk_state=%p Aml=%p size=%X\n",
		walk_state, walk_state->parser_state.aml, walk_state->parser_state.aml_size));


	/* Create and initialize a new thread state */

	thread = acpi_ut_create_thread_state ();
	if (!thread) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	walk_state->thread = thread;
	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 (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 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)) {
			ACPI_REPORT_METHOD_ERROR ("Method execution failed",
				walk_state->method_node, NULL, status);

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

			if ((status == AE_ALREADY_EXISTS) &&
				(!walk_state->method_desc->method.semaphore)) {
				/*
				 * This method is marked not_serialized, but it tried to create a named
				 * object, causing the second thread entrance to fail.  We will workaround
				 * this by marking the method permanently as Serialized.
				 */
				walk_state->method_desc->method.method_flags |= AML_METHOD_SERIALIZED;
				walk_state->method_desc->method.concurrency = 1;
			}
		}

		if (walk_state->method_desc) {
			/* Decrement the thread count on the method parse tree */

			if (walk_state->method_desc->method.thread_count) {
				walk_state->method_desc->method.thread_count--;
			}
		}

		/* 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,
		 * there's lots of cleanup to do
		 */
		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) {
			terminate_status = acpi_ds_terminate_control_method (walk_state);
			if (ACPI_FAILURE (terminate_status)) {
				ACPI_REPORT_ERROR ((
					"Could not terminate control method properly\n"));

				/* Ignore error and continue */
			}
		}

		/* 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, "return_value=%p, State=%p\n",
			walk_state->return_desc, 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
				 */
				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 */

				acpi_ut_remove_reference (previous_walk_state->return_desc);
			}
		}

		/*
		 * Just completed a 1st-level method, save the final internal return
		 * value (if any)
		 */
		else if (previous_walk_state->caller_return_desc) {
			*(previous_walk_state->caller_return_desc) = previous_walk_state->return_desc; /* NULL if no return value */
		}
		else if (previous_walk_state->return_desc) {
			/* Caller doesn't want it, must delete it */

			acpi_ut_remove_reference (previous_walk_state->return_desc);
		}

		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);
}