xref: /linux/drivers/acpi/acpica/psparse.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /******************************************************************************
2  *
3  * Module Name: psparse - Parser top level AML parse routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
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.
25  *
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.
29  *
30  * NO WARRANTY
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
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 /*
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[]
51  */
52 
53 #include <acpi/acpi.h>
54 #include "accommon.h"
55 #include "acparser.h"
56 #include "acdispat.h"
57 #include "amlcode.h"
58 #include "acinterp.h"
59 
60 #define _COMPONENT          ACPI_PARSER
61 ACPI_MODULE_NAME("psparse")
62 
63 /*******************************************************************************
64  *
65  * FUNCTION:    acpi_ps_get_opcode_size
66  *
67  * PARAMETERS:  opcode          - An AML opcode
68  *
69  * RETURN:      Size of the opcode, in bytes (1 or 2)
70  *
71  * DESCRIPTION: Get the size of the current opcode.
72  *
73  ******************************************************************************/
74 u32 acpi_ps_get_opcode_size(u32 opcode)
75 {
76 
77 	/* Extended (2-byte) opcode if > 255 */
78 
79 	if (opcode > 0x00FF) {
80 		return (2);
81 	}
82 
83 	/* Otherwise, just a single byte opcode */
84 
85 	return (1);
86 }
87 
88 /*******************************************************************************
89  *
90  * FUNCTION:    acpi_ps_peek_opcode
91  *
92  * PARAMETERS:  parser_state        - A parser state object
93  *
94  * RETURN:      Next AML opcode
95  *
96  * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
97  *
98  ******************************************************************************/
99 
100 u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state)
101 {
102 	u8 *aml;
103 	u16 opcode;
104 
105 	aml = parser_state->aml;
106 	opcode = (u16) ACPI_GET8(aml);
107 
108 	if (opcode == AML_EXTENDED_OP_PREFIX) {
109 
110 		/* Extended opcode, get the second opcode byte */
111 
112 		aml++;
113 		opcode = (u16) ((opcode << 8) | ACPI_GET8(aml));
114 	}
115 
116 	return (opcode);
117 }
118 
119 /*******************************************************************************
120  *
121  * FUNCTION:    acpi_ps_complete_this_op
122  *
123  * PARAMETERS:  walk_state      - Current State
124  *              op              - Op to complete
125  *
126  * RETURN:      Status
127  *
128  * DESCRIPTION: Perform any cleanup at the completion of an Op.
129  *
130  ******************************************************************************/
131 
132 acpi_status
133 acpi_ps_complete_this_op(struct acpi_walk_state * walk_state,
134 			 union acpi_parse_object * op)
135 {
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;
141 
142 	ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op);
143 
144 	/* Check for null Op, can happen if AML code is corrupt */
145 
146 	if (!op) {
147 		return_ACPI_STATUS(AE_OK);	/* OK for now */
148 	}
149 
150 	acpi_ex_stop_trace_opcode(op, walk_state);
151 
152 	/* Delete this op and the subtree below it if asked to */
153 
154 	if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) !=
155 	     ACPI_PARSE_DELETE_TREE)
156 	    || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
157 		return_ACPI_STATUS(AE_OK);
158 	}
159 
160 	/* Make sure that we only delete this subtree */
161 
162 	if (op->common.parent) {
163 		prev = op->common.parent->common.value.arg;
164 		if (!prev) {
165 
166 			/* Nothing more to do */
167 
168 			goto cleanup;
169 		}
170 
171 		/*
172 		 * Check if we need to replace the operator and its subtree
173 		 * with a return value op (placeholder op)
174 		 */
175 		parent_info =
176 		    acpi_ps_get_opcode_info(op->common.parent->common.
177 					    aml_opcode);
178 
179 		switch (parent_info->class) {
180 		case AML_CLASS_CONTROL:
181 
182 			break;
183 
184 		case AML_CLASS_CREATE:
185 			/*
186 			 * These opcodes contain term_arg operands. The current
187 			 * op must be replaced by a placeholder return op
188 			 */
189 			replacement_op =
190 			    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP,
191 					     op->common.aml);
192 			if (!replacement_op) {
193 				status = AE_NO_MEMORY;
194 			}
195 			break;
196 
197 		case AML_CLASS_NAMED_OBJECT:
198 			/*
199 			 * These opcodes contain term_arg operands. The current
200 			 * op must be replaced by a placeholder return op
201 			 */
202 			if ((op->common.parent->common.aml_opcode ==
203 			     AML_REGION_OP)
204 			    || (op->common.parent->common.aml_opcode ==
205 				AML_DATA_REGION_OP)
206 			    || (op->common.parent->common.aml_opcode ==
207 				AML_BUFFER_OP)
208 			    || (op->common.parent->common.aml_opcode ==
209 				AML_PACKAGE_OP)
210 			    || (op->common.parent->common.aml_opcode ==
211 				AML_BANK_FIELD_OP)
212 			    || (op->common.parent->common.aml_opcode ==
213 				AML_VAR_PACKAGE_OP)) {
214 				replacement_op =
215 				    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP,
216 						     op->common.aml);
217 				if (!replacement_op) {
218 					status = AE_NO_MEMORY;
219 				}
220 			} else
221 			    if ((op->common.parent->common.aml_opcode ==
222 				 AML_NAME_OP)
223 				&& (walk_state->pass_number <=
224 				    ACPI_IMODE_LOAD_PASS2)) {
225 				if ((op->common.aml_opcode == AML_BUFFER_OP)
226 				    || (op->common.aml_opcode == AML_PACKAGE_OP)
227 				    || (op->common.aml_opcode ==
228 					AML_VAR_PACKAGE_OP)) {
229 					replacement_op =
230 					    acpi_ps_alloc_op(op->common.
231 							     aml_opcode,
232 							     op->common.aml);
233 					if (!replacement_op) {
234 						status = AE_NO_MEMORY;
235 					} else {
236 						replacement_op->named.data =
237 						    op->named.data;
238 						replacement_op->named.length =
239 						    op->named.length;
240 					}
241 				}
242 			}
243 			break;
244 
245 		default:
246 
247 			replacement_op =
248 			    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP,
249 					     op->common.aml);
250 			if (!replacement_op) {
251 				status = AE_NO_MEMORY;
252 			}
253 		}
254 
255 		/* We must unlink this op from the parent tree */
256 
257 		if (prev == op) {
258 
259 			/* This op is the first in the list */
260 
261 			if (replacement_op) {
262 				replacement_op->common.parent =
263 				    op->common.parent;
264 				replacement_op->common.value.arg = NULL;
265 				replacement_op->common.node = op->common.node;
266 				op->common.parent->common.value.arg =
267 				    replacement_op;
268 				replacement_op->common.next = op->common.next;
269 			} else {
270 				op->common.parent->common.value.arg =
271 				    op->common.next;
272 			}
273 		}
274 
275 		/* Search the parent list */
276 
277 		else
278 			while (prev) {
279 
280 				/* Traverse all siblings in the parent's argument list */
281 
282 				next = prev->common.next;
283 				if (next == op) {
284 					if (replacement_op) {
285 						replacement_op->common.parent =
286 						    op->common.parent;
287 						replacement_op->common.value.
288 						    arg = NULL;
289 						replacement_op->common.node =
290 						    op->common.node;
291 						prev->common.next =
292 						    replacement_op;
293 						replacement_op->common.next =
294 						    op->common.next;
295 						next = NULL;
296 					} else {
297 						prev->common.next =
298 						    op->common.next;
299 						next = NULL;
300 					}
301 				}
302 				prev = next;
303 			}
304 	}
305 
306 cleanup:
307 
308 	/* Now we can actually delete the subtree rooted at Op */
309 
310 	acpi_ps_delete_parse_tree(op);
311 	return_ACPI_STATUS(status);
312 }
313 
314 /*******************************************************************************
315  *
316  * FUNCTION:    acpi_ps_next_parse_state
317  *
318  * PARAMETERS:  walk_state          - Current state
319  *              op                  - Current parse op
320  *              callback_status     - Status from previous operation
321  *
322  * RETURN:      Status
323  *
324  * DESCRIPTION: Update the parser state based upon the return exception from
325  *              the parser callback.
326  *
327  ******************************************************************************/
328 
329 acpi_status
330 acpi_ps_next_parse_state(struct acpi_walk_state *walk_state,
331 			 union acpi_parse_object *op,
332 			 acpi_status callback_status)
333 {
334 	struct acpi_parse_state *parser_state = &walk_state->parser_state;
335 	acpi_status status = AE_CTRL_PENDING;
336 
337 	ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op);
338 
339 	switch (callback_status) {
340 	case AE_CTRL_TERMINATE:
341 		/*
342 		 * A control method was terminated via a RETURN statement.
343 		 * The walk of this method is complete.
344 		 */
345 		parser_state->aml = parser_state->aml_end;
346 		status = AE_CTRL_TERMINATE;
347 		break;
348 
349 	case AE_CTRL_BREAK:
350 
351 		parser_state->aml = walk_state->aml_last_while;
352 		walk_state->control_state->common.value = FALSE;
353 		status = AE_CTRL_BREAK;
354 		break;
355 
356 	case AE_CTRL_CONTINUE:
357 
358 		parser_state->aml = walk_state->aml_last_while;
359 		status = AE_CTRL_CONTINUE;
360 		break;
361 
362 	case AE_CTRL_PENDING:
363 
364 		parser_state->aml = walk_state->aml_last_while;
365 		break;
366 
367 #if 0
368 	case AE_CTRL_SKIP:
369 
370 		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
371 		status = AE_OK;
372 		break;
373 #endif
374 
375 	case AE_CTRL_TRUE:
376 		/*
377 		 * Predicate of an IF was true, and we are at the matching ELSE.
378 		 * Just close out this package
379 		 */
380 		parser_state->aml = acpi_ps_get_next_package_end(parser_state);
381 		status = AE_CTRL_PENDING;
382 		break;
383 
384 	case AE_CTRL_FALSE:
385 		/*
386 		 * Either an IF/WHILE Predicate was false or we encountered a BREAK
387 		 * opcode. In both cases, we do not execute the rest of the
388 		 * package;  We simply close out the parent (finishing the walk of
389 		 * this branch of the tree) and continue execution at the parent
390 		 * level.
391 		 */
392 		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
393 
394 		/* In the case of a BREAK, just force a predicate (if any) to FALSE */
395 
396 		walk_state->control_state->common.value = FALSE;
397 		status = AE_CTRL_END;
398 		break;
399 
400 	case AE_CTRL_TRANSFER:
401 
402 		/* A method call (invocation) -- transfer control */
403 
404 		status = AE_CTRL_TRANSFER;
405 		walk_state->prev_op = op;
406 		walk_state->method_call_op = op;
407 		walk_state->method_call_node =
408 		    (op->common.value.arg)->common.node;
409 
410 		/* Will return value (if any) be used by the caller? */
411 
412 		walk_state->return_used =
413 		    acpi_ds_is_result_used(op, walk_state);
414 		break;
415 
416 	default:
417 
418 		status = callback_status;
419 		if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
420 			status = AE_OK;
421 		}
422 		break;
423 	}
424 
425 	return_ACPI_STATUS(status);
426 }
427 
428 /*******************************************************************************
429  *
430  * FUNCTION:    acpi_ps_parse_aml
431  *
432  * PARAMETERS:  walk_state      - Current state
433  *
434  *
435  * RETURN:      Status
436  *
437  * DESCRIPTION: Parse raw AML and return a tree of ops
438  *
439  ******************************************************************************/
440 
441 acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
442 {
443 	acpi_status status;
444 	struct acpi_thread_state *thread;
445 	struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list;
446 	struct acpi_walk_state *previous_walk_state;
447 
448 	ACPI_FUNCTION_TRACE(ps_parse_aml);
449 
450 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
451 			  "Entered with WalkState=%p Aml=%p size=%X\n",
452 			  walk_state, walk_state->parser_state.aml,
453 			  walk_state->parser_state.aml_size));
454 
455 	if (!walk_state->parser_state.aml) {
456 		return_ACPI_STATUS(AE_NULL_OBJECT);
457 	}
458 
459 	/* Create and initialize a new thread state */
460 
461 	thread = acpi_ut_create_thread_state();
462 	if (!thread) {
463 		if (walk_state->method_desc) {
464 
465 			/* Executing a control method - additional cleanup */
466 
467 			acpi_ds_terminate_control_method(walk_state->
468 							 method_desc,
469 							 walk_state);
470 		}
471 
472 		acpi_ds_delete_walk_state(walk_state);
473 		return_ACPI_STATUS(AE_NO_MEMORY);
474 	}
475 
476 	walk_state->thread = thread;
477 
478 	/*
479 	 * If executing a method, the starting sync_level is this method's
480 	 * sync_level
481 	 */
482 	if (walk_state->method_desc) {
483 		walk_state->thread->current_sync_level =
484 		    walk_state->method_desc->method.sync_level;
485 	}
486 
487 	acpi_ds_push_walk_state(walk_state, thread);
488 
489 	/*
490 	 * This global allows the AML debugger to get a handle to the currently
491 	 * executing control method.
492 	 */
493 	acpi_gbl_current_walk_list = thread;
494 
495 	/*
496 	 * Execute the walk loop as long as there is a valid Walk State. This
497 	 * handles nested control method invocations without recursion.
498 	 */
499 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));
500 
501 	status = AE_OK;
502 	while (walk_state) {
503 		if (ACPI_SUCCESS(status)) {
504 			/*
505 			 * The parse_loop executes AML until the method terminates
506 			 * or calls another method.
507 			 */
508 			status = acpi_ps_parse_loop(walk_state);
509 		}
510 
511 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
512 				  "Completed one call to walk loop, %s State=%p\n",
513 				  acpi_format_exception(status), walk_state));
514 
515 		if (status == AE_CTRL_TRANSFER) {
516 			/*
517 			 * A method call was detected.
518 			 * Transfer control to the called control method
519 			 */
520 			status =
521 			    acpi_ds_call_control_method(thread, walk_state,
522 							NULL);
523 			if (ACPI_FAILURE(status)) {
524 				status =
525 				    acpi_ds_method_error(status, walk_state);
526 			}
527 
528 			/*
529 			 * If the transfer to the new method method call worked, a new walk
530 			 * state was created -- get it
531 			 */
532 			walk_state = acpi_ds_get_current_walk_state(thread);
533 			continue;
534 		} else if (status == AE_CTRL_TERMINATE) {
535 			status = AE_OK;
536 		} else if ((status != AE_OK) && (walk_state->method_desc)) {
537 
538 			/* Either the method parse or actual execution failed */
539 
540 			ACPI_ERROR_METHOD("Method parse/execution failed",
541 					  walk_state->method_node, NULL,
542 					  status);
543 
544 			/* Check for possible multi-thread reentrancy problem */
545 
546 			if ((status == AE_ALREADY_EXISTS) &&
547 			    (!(walk_state->method_desc->method.
548 			       info_flags & ACPI_METHOD_SERIALIZED))) {
549 				/*
550 				 * Method is not serialized and tried to create an object
551 				 * twice. The probable cause is that the method cannot
552 				 * handle reentrancy. Mark as "pending serialized" now, and
553 				 * then mark "serialized" when the last thread exits.
554 				 */
555 				walk_state->method_desc->method.info_flags |=
556 				    ACPI_METHOD_SERIALIZED_PENDING;
557 			}
558 		}
559 
560 		/* We are done with this walk, move on to the parent if any */
561 
562 		walk_state = acpi_ds_pop_walk_state(thread);
563 
564 		/* Reset the current scope to the beginning of scope stack */
565 
566 		acpi_ds_scope_stack_clear(walk_state);
567 
568 		/*
569 		 * If we just returned from the execution of a control method or if we
570 		 * encountered an error during the method parse phase, there's lots of
571 		 * cleanup to do
572 		 */
573 		if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
574 		     ACPI_PARSE_EXECUTE) || (ACPI_FAILURE(status))) {
575 			acpi_ds_terminate_control_method(walk_state->
576 							 method_desc,
577 							 walk_state);
578 		}
579 
580 		/* Delete this walk state and all linked control states */
581 
582 		acpi_ps_cleanup_scope(&walk_state->parser_state);
583 		previous_walk_state = walk_state;
584 
585 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
586 				  "ReturnValue=%p, ImplicitValue=%p State=%p\n",
587 				  walk_state->return_desc,
588 				  walk_state->implicit_return_obj, walk_state));
589 
590 		/* Check if we have restarted a preempted walk */
591 
592 		walk_state = acpi_ds_get_current_walk_state(thread);
593 		if (walk_state) {
594 			if (ACPI_SUCCESS(status)) {
595 				/*
596 				 * There is another walk state, restart it.
597 				 * If the method return value is not used by the parent,
598 				 * The object is deleted
599 				 */
600 				if (!previous_walk_state->return_desc) {
601 					/*
602 					 * In slack mode execution, if there is no return value
603 					 * we should implicitly return zero (0) as a default value.
604 					 */
605 					if (acpi_gbl_enable_interpreter_slack &&
606 					    !previous_walk_state->
607 					    implicit_return_obj) {
608 						previous_walk_state->
609 						    implicit_return_obj =
610 						    acpi_ut_create_integer_object
611 						    ((u64) 0);
612 						if (!previous_walk_state->
613 						    implicit_return_obj) {
614 							return_ACPI_STATUS
615 							    (AE_NO_MEMORY);
616 						}
617 					}
618 
619 					/* Restart the calling control method */
620 
621 					status =
622 					    acpi_ds_restart_control_method
623 					    (walk_state,
624 					     previous_walk_state->
625 					     implicit_return_obj);
626 				} else {
627 					/*
628 					 * We have a valid return value, delete any implicit
629 					 * return value.
630 					 */
631 					acpi_ds_clear_implicit_return
632 					    (previous_walk_state);
633 
634 					status =
635 					    acpi_ds_restart_control_method
636 					    (walk_state,
637 					     previous_walk_state->return_desc);
638 				}
639 				if (ACPI_SUCCESS(status)) {
640 					walk_state->walk_type |=
641 					    ACPI_WALK_METHOD_RESTART;
642 				}
643 			} else {
644 				/* On error, delete any return object or implicit return */
645 
646 				acpi_ut_remove_reference(previous_walk_state->
647 							 return_desc);
648 				acpi_ds_clear_implicit_return
649 				    (previous_walk_state);
650 			}
651 		}
652 
653 		/*
654 		 * Just completed a 1st-level method, save the final internal return
655 		 * value (if any)
656 		 */
657 		else if (previous_walk_state->caller_return_desc) {
658 			if (previous_walk_state->implicit_return_obj) {
659 				*(previous_walk_state->caller_return_desc) =
660 				    previous_walk_state->implicit_return_obj;
661 			} else {
662 				/* NULL if no return value */
663 
664 				*(previous_walk_state->caller_return_desc) =
665 				    previous_walk_state->return_desc;
666 			}
667 		} else {
668 			if (previous_walk_state->return_desc) {
669 
670 				/* Caller doesn't want it, must delete it */
671 
672 				acpi_ut_remove_reference(previous_walk_state->
673 							 return_desc);
674 			}
675 			if (previous_walk_state->implicit_return_obj) {
676 
677 				/* Caller doesn't want it, must delete it */
678 
679 				acpi_ut_remove_reference(previous_walk_state->
680 							 implicit_return_obj);
681 			}
682 		}
683 
684 		acpi_ds_delete_walk_state(previous_walk_state);
685 	}
686 
687 	/* Normal exit */
688 
689 	acpi_ex_release_all_mutexes(thread);
690 	acpi_ut_delete_generic_state(ACPI_CAST_PTR
691 				     (union acpi_generic_state, thread));
692 	acpi_gbl_current_walk_list = prev_walk_list;
693 	return_ACPI_STATUS(status);
694 }
695