1 /******************************************************************************
3 * Module Name: psparse - Parser top level AML parse routines
5 *****************************************************************************/
8 * Copyright (C) 2000 - 2011, Intel Corp.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
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35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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41 * POSSIBILITY OF SUCH DAMAGES.
45 * Parse the AML and build an operation tree as most interpreters,
46 * like Perl, do. Parsing is done by hand rather than with a YACC
47 * generated parser to tightly constrain stack and dynamic memory
48 * usage. At the same time, parsing is kept flexible and the code
49 * fairly compact by parsing based on a list of AML opcode
50 * templates in aml_op_info[]
53 #include <acpi/acpi.h>
60 #define _COMPONENT ACPI_PARSER
61 ACPI_MODULE_NAME("psparse")
63 /*******************************************************************************
65 * FUNCTION: acpi_ps_get_opcode_size
67 * PARAMETERS: Opcode - An AML opcode
69 * RETURN: Size of the opcode, in bytes (1 or 2)
71 * DESCRIPTION: Get the size of the current opcode.
73 ******************************************************************************/
74 u32
acpi_ps_get_opcode_size(u32 opcode
)
77 /* Extended (2-byte) opcode if > 255 */
79 if (opcode
> 0x00FF) {
83 /* Otherwise, just a single byte opcode */
88 /*******************************************************************************
90 * FUNCTION: acpi_ps_peek_opcode
92 * PARAMETERS: parser_state - A parser state object
94 * RETURN: Next AML opcode
96 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
98 ******************************************************************************/
100 u16
acpi_ps_peek_opcode(struct acpi_parse_state
* parser_state
)
105 aml
= parser_state
->aml
;
106 opcode
= (u16
) ACPI_GET8(aml
);
108 if (opcode
== AML_EXTENDED_OP_PREFIX
) {
110 /* Extended opcode, get the second opcode byte */
113 opcode
= (u16
) ((opcode
<< 8) | ACPI_GET8(aml
));
119 /*******************************************************************************
121 * FUNCTION: acpi_ps_complete_this_op
123 * PARAMETERS: walk_state - Current State
124 * Op - Op to complete
128 * DESCRIPTION: Perform any cleanup at the completion of an Op.
130 ******************************************************************************/
133 acpi_ps_complete_this_op(struct acpi_walk_state
* walk_state
,
134 union acpi_parse_object
* op
)
136 union acpi_parse_object
*prev
;
137 union acpi_parse_object
*next
;
138 const struct acpi_opcode_info
*parent_info
;
139 union acpi_parse_object
*replacement_op
= NULL
;
140 acpi_status status
= AE_OK
;
142 ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op
, op
);
144 /* Check for null Op, can happen if AML code is corrupt */
147 return_ACPI_STATUS(AE_OK
); /* OK for now */
150 /* Delete this op and the subtree below it if asked to */
152 if (((walk_state
->parse_flags
& ACPI_PARSE_TREE_MASK
) !=
153 ACPI_PARSE_DELETE_TREE
)
154 || (walk_state
->op_info
->class == AML_CLASS_ARGUMENT
)) {
155 return_ACPI_STATUS(AE_OK
);
158 /* Make sure that we only delete this subtree */
160 if (op
->common
.parent
) {
161 prev
= op
->common
.parent
->common
.value
.arg
;
164 /* Nothing more to do */
170 * Check if we need to replace the operator and its subtree
171 * with a return value op (placeholder op)
174 acpi_ps_get_opcode_info(op
->common
.parent
->common
.
177 switch (parent_info
->class) {
178 case AML_CLASS_CONTROL
:
181 case AML_CLASS_CREATE
:
184 * These opcodes contain term_arg operands. The current
185 * op must be replaced by a placeholder return op
188 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP
);
189 if (!replacement_op
) {
190 status
= AE_NO_MEMORY
;
194 case AML_CLASS_NAMED_OBJECT
:
197 * These opcodes contain term_arg operands. The current
198 * op must be replaced by a placeholder return op
200 if ((op
->common
.parent
->common
.aml_opcode
==
202 || (op
->common
.parent
->common
.aml_opcode
==
204 || (op
->common
.parent
->common
.aml_opcode
==
206 || (op
->common
.parent
->common
.aml_opcode
==
208 || (op
->common
.parent
->common
.aml_opcode
==
210 || (op
->common
.parent
->common
.aml_opcode
==
211 AML_VAR_PACKAGE_OP
)) {
213 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP
);
214 if (!replacement_op
) {
215 status
= AE_NO_MEMORY
;
218 if ((op
->common
.parent
->common
.aml_opcode
==
220 && (walk_state
->pass_number
<=
221 ACPI_IMODE_LOAD_PASS2
)) {
222 if ((op
->common
.aml_opcode
== AML_BUFFER_OP
)
223 || (op
->common
.aml_opcode
== AML_PACKAGE_OP
)
224 || (op
->common
.aml_opcode
==
225 AML_VAR_PACKAGE_OP
)) {
227 acpi_ps_alloc_op(op
->common
.
229 if (!replacement_op
) {
230 status
= AE_NO_MEMORY
;
232 replacement_op
->named
.data
=
234 replacement_op
->named
.length
=
244 acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP
);
245 if (!replacement_op
) {
246 status
= AE_NO_MEMORY
;
250 /* We must unlink this op from the parent tree */
254 /* This op is the first in the list */
256 if (replacement_op
) {
257 replacement_op
->common
.parent
=
259 replacement_op
->common
.value
.arg
= NULL
;
260 replacement_op
->common
.node
= op
->common
.node
;
261 op
->common
.parent
->common
.value
.arg
=
263 replacement_op
->common
.next
= op
->common
.next
;
265 op
->common
.parent
->common
.value
.arg
=
270 /* Search the parent list */
275 /* Traverse all siblings in the parent's argument list */
277 next
= prev
->common
.next
;
279 if (replacement_op
) {
280 replacement_op
->common
.parent
=
282 replacement_op
->common
.value
.
284 replacement_op
->common
.node
=
288 replacement_op
->common
.next
=
303 /* Now we can actually delete the subtree rooted at Op */
305 acpi_ps_delete_parse_tree(op
);
306 return_ACPI_STATUS(status
);
309 /*******************************************************************************
311 * FUNCTION: acpi_ps_next_parse_state
313 * PARAMETERS: walk_state - Current state
314 * Op - Current parse op
315 * callback_status - Status from previous operation
319 * DESCRIPTION: Update the parser state based upon the return exception from
320 * the parser callback.
322 ******************************************************************************/
325 acpi_ps_next_parse_state(struct acpi_walk_state
*walk_state
,
326 union acpi_parse_object
*op
,
327 acpi_status callback_status
)
329 struct acpi_parse_state
*parser_state
= &walk_state
->parser_state
;
330 acpi_status status
= AE_CTRL_PENDING
;
332 ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state
, op
);
334 switch (callback_status
) {
335 case AE_CTRL_TERMINATE
:
337 * A control method was terminated via a RETURN statement.
338 * The walk of this method is complete.
340 parser_state
->aml
= parser_state
->aml_end
;
341 status
= AE_CTRL_TERMINATE
;
346 parser_state
->aml
= walk_state
->aml_last_while
;
347 walk_state
->control_state
->common
.value
= FALSE
;
348 status
= AE_CTRL_BREAK
;
351 case AE_CTRL_CONTINUE
:
353 parser_state
->aml
= walk_state
->aml_last_while
;
354 status
= AE_CTRL_CONTINUE
;
357 case AE_CTRL_PENDING
:
359 parser_state
->aml
= walk_state
->aml_last_while
;
365 parser_state
->aml
= parser_state
->scope
->parse_scope
.pkg_end
;
372 * Predicate of an IF was true, and we are at the matching ELSE.
373 * Just close out this package
375 parser_state
->aml
= acpi_ps_get_next_package_end(parser_state
);
376 status
= AE_CTRL_PENDING
;
381 * Either an IF/WHILE Predicate was false or we encountered a BREAK
382 * opcode. In both cases, we do not execute the rest of the
383 * package; We simply close out the parent (finishing the walk of
384 * this branch of the tree) and continue execution at the parent
387 parser_state
->aml
= parser_state
->scope
->parse_scope
.pkg_end
;
389 /* In the case of a BREAK, just force a predicate (if any) to FALSE */
391 walk_state
->control_state
->common
.value
= FALSE
;
392 status
= AE_CTRL_END
;
395 case AE_CTRL_TRANSFER
:
397 /* A method call (invocation) -- transfer control */
399 status
= AE_CTRL_TRANSFER
;
400 walk_state
->prev_op
= op
;
401 walk_state
->method_call_op
= op
;
402 walk_state
->method_call_node
=
403 (op
->common
.value
.arg
)->common
.node
;
405 /* Will return value (if any) be used by the caller? */
407 walk_state
->return_used
=
408 acpi_ds_is_result_used(op
, walk_state
);
413 status
= callback_status
;
414 if ((callback_status
& AE_CODE_MASK
) == AE_CODE_CONTROL
) {
420 return_ACPI_STATUS(status
);
423 /*******************************************************************************
425 * FUNCTION: acpi_ps_parse_aml
427 * PARAMETERS: walk_state - Current state
432 * DESCRIPTION: Parse raw AML and return a tree of ops
434 ******************************************************************************/
436 acpi_status
acpi_ps_parse_aml(struct acpi_walk_state
*walk_state
)
439 struct acpi_thread_state
*thread
;
440 struct acpi_thread_state
*prev_walk_list
= acpi_gbl_current_walk_list
;
441 struct acpi_walk_state
*previous_walk_state
;
443 ACPI_FUNCTION_TRACE(ps_parse_aml
);
445 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
,
446 "Entered with WalkState=%p Aml=%p size=%X\n",
447 walk_state
, walk_state
->parser_state
.aml
,
448 walk_state
->parser_state
.aml_size
));
450 if (!walk_state
->parser_state
.aml
) {
451 return_ACPI_STATUS(AE_NULL_OBJECT
);
454 /* Create and initialize a new thread state */
456 thread
= acpi_ut_create_thread_state();
458 if (walk_state
->method_desc
) {
460 /* Executing a control method - additional cleanup */
462 acpi_ds_terminate_control_method(
463 walk_state
->method_desc
, walk_state
);
466 acpi_ds_delete_walk_state(walk_state
);
467 return_ACPI_STATUS(AE_NO_MEMORY
);
470 walk_state
->thread
= thread
;
473 * If executing a method, the starting sync_level is this method's
476 if (walk_state
->method_desc
) {
477 walk_state
->thread
->current_sync_level
=
478 walk_state
->method_desc
->method
.sync_level
;
481 acpi_ds_push_walk_state(walk_state
, thread
);
484 * This global allows the AML debugger to get a handle to the currently
485 * executing control method.
487 acpi_gbl_current_walk_list
= thread
;
490 * Execute the walk loop as long as there is a valid Walk State. This
491 * handles nested control method invocations without recursion.
493 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
, "State=%p\n", walk_state
));
497 if (ACPI_SUCCESS(status
)) {
499 * The parse_loop executes AML until the method terminates
500 * or calls another method.
502 status
= acpi_ps_parse_loop(walk_state
);
505 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
,
506 "Completed one call to walk loop, %s State=%p\n",
507 acpi_format_exception(status
), walk_state
));
509 if (status
== AE_CTRL_TRANSFER
) {
511 * A method call was detected.
512 * Transfer control to the called control method
515 acpi_ds_call_control_method(thread
, walk_state
,
517 if (ACPI_FAILURE(status
)) {
519 acpi_ds_method_error(status
, walk_state
);
523 * If the transfer to the new method method call worked, a new walk
524 * state was created -- get it
526 walk_state
= acpi_ds_get_current_walk_state(thread
);
528 } else if (status
== AE_CTRL_TERMINATE
) {
530 } else if ((status
!= AE_OK
) && (walk_state
->method_desc
)) {
532 /* Either the method parse or actual execution failed */
534 ACPI_ERROR_METHOD("Method parse/execution failed",
535 walk_state
->method_node
, NULL
,
538 /* Check for possible multi-thread reentrancy problem */
540 if ((status
== AE_ALREADY_EXISTS
) &&
541 (!(walk_state
->method_desc
->method
.
542 info_flags
& ACPI_METHOD_SERIALIZED
))) {
544 * Method is not serialized and tried to create an object
545 * twice. The probable cause is that the method cannot
546 * handle reentrancy. Mark as "pending serialized" now, and
547 * then mark "serialized" when the last thread exits.
549 walk_state
->method_desc
->method
.info_flags
|=
550 ACPI_METHOD_SERIALIZED_PENDING
;
554 /* We are done with this walk, move on to the parent if any */
556 walk_state
= acpi_ds_pop_walk_state(thread
);
558 /* Reset the current scope to the beginning of scope stack */
560 acpi_ds_scope_stack_clear(walk_state
);
563 * If we just returned from the execution of a control method or if we
564 * encountered an error during the method parse phase, there's lots of
567 if (((walk_state
->parse_flags
& ACPI_PARSE_MODE_MASK
) ==
568 ACPI_PARSE_EXECUTE
) || (ACPI_FAILURE(status
))) {
569 acpi_ds_terminate_control_method(walk_state
->
574 /* Delete this walk state and all linked control states */
576 acpi_ps_cleanup_scope(&walk_state
->parser_state
);
577 previous_walk_state
= walk_state
;
579 ACPI_DEBUG_PRINT((ACPI_DB_PARSE
,
580 "ReturnValue=%p, ImplicitValue=%p State=%p\n",
581 walk_state
->return_desc
,
582 walk_state
->implicit_return_obj
, walk_state
));
584 /* Check if we have restarted a preempted walk */
586 walk_state
= acpi_ds_get_current_walk_state(thread
);
588 if (ACPI_SUCCESS(status
)) {
590 * There is another walk state, restart it.
591 * If the method return value is not used by the parent,
592 * The object is deleted
594 if (!previous_walk_state
->return_desc
) {
596 * In slack mode execution, if there is no return value
597 * we should implicitly return zero (0) as a default value.
599 if (acpi_gbl_enable_interpreter_slack
&&
600 !previous_walk_state
->
601 implicit_return_obj
) {
602 previous_walk_state
->
603 implicit_return_obj
=
604 acpi_ut_create_integer_object
606 if (!previous_walk_state
->
607 implicit_return_obj
) {
613 /* Restart the calling control method */
616 acpi_ds_restart_control_method
618 previous_walk_state
->
619 implicit_return_obj
);
622 * We have a valid return value, delete any implicit
625 acpi_ds_clear_implicit_return
626 (previous_walk_state
);
629 acpi_ds_restart_control_method
631 previous_walk_state
->return_desc
);
633 if (ACPI_SUCCESS(status
)) {
634 walk_state
->walk_type
|=
635 ACPI_WALK_METHOD_RESTART
;
638 /* On error, delete any return object or implicit return */
640 acpi_ut_remove_reference(previous_walk_state
->
642 acpi_ds_clear_implicit_return
643 (previous_walk_state
);
648 * Just completed a 1st-level method, save the final internal return
651 else if (previous_walk_state
->caller_return_desc
) {
652 if (previous_walk_state
->implicit_return_obj
) {
653 *(previous_walk_state
->caller_return_desc
) =
654 previous_walk_state
->implicit_return_obj
;
656 /* NULL if no return value */
658 *(previous_walk_state
->caller_return_desc
) =
659 previous_walk_state
->return_desc
;
662 if (previous_walk_state
->return_desc
) {
664 /* Caller doesn't want it, must delete it */
666 acpi_ut_remove_reference(previous_walk_state
->
669 if (previous_walk_state
->implicit_return_obj
) {
671 /* Caller doesn't want it, must delete it */
673 acpi_ut_remove_reference(previous_walk_state
->
674 implicit_return_obj
);
678 acpi_ds_delete_walk_state(previous_walk_state
);
683 acpi_ex_release_all_mutexes(thread
);
684 acpi_ut_delete_generic_state(ACPI_CAST_PTR
685 (union acpi_generic_state
, thread
));
686 acpi_gbl_current_walk_list
= prev_walk_list
;
687 return_ACPI_STATUS(status
);