xref: /linux/drivers/acpi/acpica/psloop.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /******************************************************************************
2  *
3  * Module Name: psloop - Main AML parse loop
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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, (such as
46  * Perl) do. Parsing is done by hand rather than with a YACC generated parser
47  * to tightly constrain stack and dynamic memory usage. Parsing is kept
48  * flexible and the code fairly compact by parsing based on a list of AML
49  * opcode templates in aml_op_info[].
50  */
51 
52 #include <acpi/acpi.h>
53 #include "accommon.h"
54 #include "acinterp.h"
55 #include "acparser.h"
56 #include "acdispat.h"
57 #include "amlcode.h"
58 #include "acconvert.h"
59 
60 #define _COMPONENT          ACPI_PARSER
61 ACPI_MODULE_NAME("psloop")
62 
63 /* Local prototypes */
64 static acpi_status
65 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
66 		      u8 * aml_op_start, union acpi_parse_object *op);
67 
68 static void
69 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
70 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id);
71 
72 /*******************************************************************************
73  *
74  * FUNCTION:    acpi_ps_get_arguments
75  *
76  * PARAMETERS:  walk_state          - Current state
77  *              aml_op_start        - Op start in AML
78  *              op                  - Current Op
79  *
80  * RETURN:      Status
81  *
82  * DESCRIPTION: Get arguments for passed Op.
83  *
84  ******************************************************************************/
85 
86 static acpi_status
87 acpi_ps_get_arguments(struct acpi_walk_state *walk_state,
88 		      u8 * aml_op_start, union acpi_parse_object *op)
89 {
90 	acpi_status status = AE_OK;
91 	union acpi_parse_object *arg = NULL;
92 	const struct acpi_opcode_info *op_info;
93 
94 	ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);
95 
96 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
97 			  "Get arguments for opcode [%s]\n",
98 			  op->common.aml_op_name));
99 
100 	switch (op->common.aml_opcode) {
101 	case AML_BYTE_OP:	/* AML_BYTEDATA_ARG */
102 	case AML_WORD_OP:	/* AML_WORDDATA_ARG */
103 	case AML_DWORD_OP:	/* AML_DWORDATA_ARG */
104 	case AML_QWORD_OP:	/* AML_QWORDATA_ARG */
105 	case AML_STRING_OP:	/* AML_ASCIICHARLIST_ARG */
106 
107 		/* Fill in constant or string argument directly */
108 
109 		acpi_ps_get_next_simple_arg(&(walk_state->parser_state),
110 					    GET_CURRENT_ARG_TYPE(walk_state->
111 								 arg_types),
112 					    op);
113 		break;
114 
115 	case AML_INT_NAMEPATH_OP:	/* AML_NAMESTRING_ARG */
116 
117 		status = acpi_ps_get_next_namepath(walk_state,
118 						   &(walk_state->parser_state),
119 						   op,
120 						   ACPI_POSSIBLE_METHOD_CALL);
121 		if (ACPI_FAILURE(status)) {
122 			return_ACPI_STATUS(status);
123 		}
124 
125 		walk_state->arg_types = 0;
126 		break;
127 
128 	default:
129 		/*
130 		 * Op is not a constant or string, append each argument to the Op
131 		 */
132 		while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&
133 		       !walk_state->arg_count) {
134 			walk_state->aml = walk_state->parser_state.aml;
135 
136 			switch (op->common.aml_opcode) {
137 			case AML_METHOD_OP:
138 			case AML_BUFFER_OP:
139 			case AML_PACKAGE_OP:
140 			case AML_VARIABLE_PACKAGE_OP:
141 			case AML_WHILE_OP:
142 
143 				break;
144 
145 			default:
146 
147 				ASL_CV_CAPTURE_COMMENTS(walk_state);
148 				break;
149 			}
150 
151 			status =
152 			    acpi_ps_get_next_arg(walk_state,
153 						 &(walk_state->parser_state),
154 						 GET_CURRENT_ARG_TYPE
155 						 (walk_state->arg_types), &arg);
156 			if (ACPI_FAILURE(status)) {
157 				return_ACPI_STATUS(status);
158 			}
159 
160 			if (arg) {
161 				acpi_ps_append_arg(op, arg);
162 			}
163 
164 			INCREMENT_ARG_LIST(walk_state->arg_types);
165 		}
166 
167 		/*
168 		 * Handle executable code at "module-level". This refers to
169 		 * executable opcodes that appear outside of any control method.
170 		 */
171 		if ((walk_state->pass_number <= ACPI_IMODE_LOAD_PASS2) &&
172 		    ((walk_state->parse_flags & ACPI_PARSE_DISASSEMBLE) == 0)) {
173 			/*
174 			 * We want to skip If/Else/While constructs during Pass1 because we
175 			 * want to actually conditionally execute the code during Pass2.
176 			 *
177 			 * Except for disassembly, where we always want to walk the
178 			 * If/Else/While packages
179 			 */
180 			switch (op->common.aml_opcode) {
181 			case AML_IF_OP:
182 			case AML_ELSE_OP:
183 			case AML_WHILE_OP:
184 				/*
185 				 * Currently supported module-level opcodes are:
186 				 * IF/ELSE/WHILE. These appear to be the most common,
187 				 * and easiest to support since they open an AML
188 				 * package.
189 				 */
190 				if (walk_state->pass_number ==
191 				    ACPI_IMODE_LOAD_PASS1) {
192 					acpi_ps_link_module_code(op->common.
193 								 parent,
194 								 aml_op_start,
195 								 (u32)
196 								 (walk_state->
197 								 parser_state.
198 								 pkg_end -
199 								 aml_op_start),
200 								 walk_state->
201 								 owner_id);
202 				}
203 
204 				ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
205 						  "Pass1: Skipping an If/Else/While body\n"));
206 
207 				/* Skip body of if/else/while in pass 1 */
208 
209 				walk_state->parser_state.aml =
210 				    walk_state->parser_state.pkg_end;
211 				walk_state->arg_count = 0;
212 				break;
213 
214 			default:
215 				/*
216 				 * Check for an unsupported executable opcode at module
217 				 * level. We must be in PASS1, the parent must be a SCOPE,
218 				 * The opcode class must be EXECUTE, and the opcode must
219 				 * not be an argument to another opcode.
220 				 */
221 				if ((walk_state->pass_number ==
222 				     ACPI_IMODE_LOAD_PASS1)
223 				    && (op->common.parent->common.aml_opcode ==
224 					AML_SCOPE_OP)) {
225 					op_info =
226 					    acpi_ps_get_opcode_info(op->common.
227 								    aml_opcode);
228 					if ((op_info->class ==
229 					     AML_CLASS_EXECUTE) && (!arg)) {
230 						ACPI_WARNING((AE_INFO,
231 							      "Unsupported module-level executable opcode "
232 							      "0x%.2X at table offset 0x%.4X",
233 							      op->common.
234 							      aml_opcode,
235 							      (u32)
236 							      (ACPI_PTR_DIFF
237 							       (aml_op_start,
238 								walk_state->
239 								parser_state.
240 								aml_start) +
241 							       sizeof(struct
242 								      acpi_table_header))));
243 					}
244 				}
245 				break;
246 			}
247 		}
248 
249 		/* Special processing for certain opcodes */
250 
251 		switch (op->common.aml_opcode) {
252 		case AML_METHOD_OP:
253 			/*
254 			 * Skip parsing of control method because we don't have enough
255 			 * info in the first pass to parse it correctly.
256 			 *
257 			 * Save the length and address of the body
258 			 */
259 			op->named.data = walk_state->parser_state.aml;
260 			op->named.length = (u32)
261 			    (walk_state->parser_state.pkg_end -
262 			     walk_state->parser_state.aml);
263 
264 			/* Skip body of method */
265 
266 			walk_state->parser_state.aml =
267 			    walk_state->parser_state.pkg_end;
268 			walk_state->arg_count = 0;
269 			break;
270 
271 		case AML_BUFFER_OP:
272 		case AML_PACKAGE_OP:
273 		case AML_VARIABLE_PACKAGE_OP:
274 
275 			if ((op->common.parent) &&
276 			    (op->common.parent->common.aml_opcode ==
277 			     AML_NAME_OP)
278 			    && (walk_state->pass_number <=
279 				ACPI_IMODE_LOAD_PASS2)) {
280 				/*
281 				 * Skip parsing of Buffers and Packages because we don't have
282 				 * enough info in the first pass to parse them correctly.
283 				 */
284 				op->named.data = aml_op_start;
285 				op->named.length = (u32)
286 				    (walk_state->parser_state.pkg_end -
287 				     aml_op_start);
288 
289 				/* Skip body */
290 
291 				walk_state->parser_state.aml =
292 				    walk_state->parser_state.pkg_end;
293 				walk_state->arg_count = 0;
294 			}
295 			break;
296 
297 		case AML_WHILE_OP:
298 
299 			if (walk_state->control_state) {
300 				walk_state->control_state->control.package_end =
301 				    walk_state->parser_state.pkg_end;
302 			}
303 			break;
304 
305 		default:
306 
307 			/* No action for all other opcodes */
308 
309 			break;
310 		}
311 
312 		break;
313 	}
314 
315 	return_ACPI_STATUS(AE_OK);
316 }
317 
318 /*******************************************************************************
319  *
320  * FUNCTION:    acpi_ps_link_module_code
321  *
322  * PARAMETERS:  parent_op           - Parent parser op
323  *              aml_start           - Pointer to the AML
324  *              aml_length          - Length of executable AML
325  *              owner_id            - owner_id of module level code
326  *
327  * RETURN:      None.
328  *
329  * DESCRIPTION: Wrap the module-level code with a method object and link the
330  *              object to the global list. Note, the mutex field of the method
331  *              object is used to link multiple module-level code objects.
332  *
333  ******************************************************************************/
334 
335 static void
336 acpi_ps_link_module_code(union acpi_parse_object *parent_op,
337 			 u8 *aml_start, u32 aml_length, acpi_owner_id owner_id)
338 {
339 	union acpi_operand_object *prev;
340 	union acpi_operand_object *next;
341 	union acpi_operand_object *method_obj;
342 	struct acpi_namespace_node *parent_node;
343 
344 	ACPI_FUNCTION_TRACE(ps_link_module_code);
345 
346 	/* Get the tail of the list */
347 
348 	prev = next = acpi_gbl_module_code_list;
349 	while (next) {
350 		prev = next;
351 		next = next->method.mutex;
352 	}
353 
354 	/*
355 	 * Insert the module level code into the list. Merge it if it is
356 	 * adjacent to the previous element.
357 	 */
358 	if (!prev ||
359 	    ((prev->method.aml_start + prev->method.aml_length) != aml_start)) {
360 
361 		/* Create, initialize, and link a new temporary method object */
362 
363 		method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
364 		if (!method_obj) {
365 			return_VOID;
366 		}
367 
368 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
369 				  "Create/Link new code block: %p\n",
370 				  method_obj));
371 
372 		if (parent_op->common.node) {
373 			parent_node = parent_op->common.node;
374 		} else {
375 			parent_node = acpi_gbl_root_node;
376 		}
377 
378 		method_obj->method.aml_start = aml_start;
379 		method_obj->method.aml_length = aml_length;
380 		method_obj->method.owner_id = owner_id;
381 		method_obj->method.info_flags |= ACPI_METHOD_MODULE_LEVEL;
382 
383 		/*
384 		 * Save the parent node in next_object. This is cheating, but we
385 		 * don't want to expand the method object.
386 		 */
387 		method_obj->method.next_object =
388 		    ACPI_CAST_PTR(union acpi_operand_object, parent_node);
389 
390 		if (!prev) {
391 			acpi_gbl_module_code_list = method_obj;
392 		} else {
393 			prev->method.mutex = method_obj;
394 		}
395 	} else {
396 		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
397 				  "Appending to existing code block: %p\n",
398 				  prev));
399 
400 		prev->method.aml_length += aml_length;
401 	}
402 
403 	return_VOID;
404 }
405 
406 /*******************************************************************************
407  *
408  * FUNCTION:    acpi_ps_parse_loop
409  *
410  * PARAMETERS:  walk_state          - Current state
411  *
412  * RETURN:      Status
413  *
414  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
415  *              a tree of ops.
416  *
417  ******************************************************************************/
418 
419 acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)
420 {
421 	acpi_status status = AE_OK;
422 	union acpi_parse_object *op = NULL;	/* current op */
423 	struct acpi_parse_state *parser_state;
424 	u8 *aml_op_start = NULL;
425 
426 	ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);
427 
428 	if (walk_state->descending_callback == NULL) {
429 		return_ACPI_STATUS(AE_BAD_PARAMETER);
430 	}
431 
432 	parser_state = &walk_state->parser_state;
433 	walk_state->arg_types = 0;
434 
435 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
436 
437 	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
438 
439 		/* We are restarting a preempted control method */
440 
441 		if (acpi_ps_has_completed_scope(parser_state)) {
442 			/*
443 			 * We must check if a predicate to an IF or WHILE statement
444 			 * was just completed
445 			 */
446 			if ((parser_state->scope->parse_scope.op) &&
447 			    ((parser_state->scope->parse_scope.op->common.
448 			      aml_opcode == AML_IF_OP)
449 			     || (parser_state->scope->parse_scope.op->common.
450 				 aml_opcode == AML_WHILE_OP))
451 			    && (walk_state->control_state)
452 			    && (walk_state->control_state->common.state ==
453 				ACPI_CONTROL_PREDICATE_EXECUTING)) {
454 				/*
455 				 * A predicate was just completed, get the value of the
456 				 * predicate and branch based on that value
457 				 */
458 				walk_state->op = NULL;
459 				status =
460 				    acpi_ds_get_predicate_value(walk_state,
461 								ACPI_TO_POINTER
462 								(TRUE));
463 				if (ACPI_FAILURE(status)
464 				    && ((status & AE_CODE_MASK) !=
465 					AE_CODE_CONTROL)) {
466 					if (status == AE_AML_NO_RETURN_VALUE) {
467 						ACPI_EXCEPTION((AE_INFO, status,
468 								"Invoked method did not return a value"));
469 					}
470 
471 					ACPI_EXCEPTION((AE_INFO, status,
472 							"GetPredicate Failed"));
473 					return_ACPI_STATUS(status);
474 				}
475 
476 				status =
477 				    acpi_ps_next_parse_state(walk_state, op,
478 							     status);
479 			}
480 
481 			acpi_ps_pop_scope(parser_state, &op,
482 					  &walk_state->arg_types,
483 					  &walk_state->arg_count);
484 			ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
485 					  "Popped scope, Op=%p\n", op));
486 		} else if (walk_state->prev_op) {
487 
488 			/* We were in the middle of an op */
489 
490 			op = walk_state->prev_op;
491 			walk_state->arg_types = walk_state->prev_arg_types;
492 		}
493 	}
494 #endif
495 
496 	/* Iterative parsing loop, while there is more AML to process: */
497 
498 	while ((parser_state->aml < parser_state->aml_end) || (op)) {
499 		ASL_CV_CAPTURE_COMMENTS(walk_state);
500 
501 		aml_op_start = parser_state->aml;
502 		if (!op) {
503 			status =
504 			    acpi_ps_create_op(walk_state, aml_op_start, &op);
505 			if (ACPI_FAILURE(status)) {
506 				if (status == AE_CTRL_PARSE_CONTINUE) {
507 					continue;
508 				}
509 
510 				if (status == AE_CTRL_PARSE_PENDING) {
511 					status = AE_OK;
512 				}
513 
514 				if (status == AE_CTRL_TERMINATE) {
515 					return_ACPI_STATUS(status);
516 				}
517 
518 				status =
519 				    acpi_ps_complete_op(walk_state, &op,
520 							status);
521 				if (ACPI_FAILURE(status)) {
522 					return_ACPI_STATUS(status);
523 				}
524 
525 				continue;
526 			}
527 
528 			acpi_ex_start_trace_opcode(op, walk_state);
529 		}
530 
531 		/*
532 		 * Start arg_count at zero because we don't know if there are
533 		 * any args yet
534 		 */
535 		walk_state->arg_count = 0;
536 
537 		switch (op->common.aml_opcode) {
538 		case AML_BYTE_OP:
539 		case AML_WORD_OP:
540 		case AML_DWORD_OP:
541 		case AML_QWORD_OP:
542 
543 			break;
544 
545 		default:
546 
547 			ASL_CV_CAPTURE_COMMENTS(walk_state);
548 			break;
549 		}
550 
551 		/* Are there any arguments that must be processed? */
552 
553 		if (walk_state->arg_types) {
554 
555 			/* Get arguments */
556 
557 			status =
558 			    acpi_ps_get_arguments(walk_state, aml_op_start, op);
559 			if (ACPI_FAILURE(status)) {
560 				status =
561 				    acpi_ps_complete_op(walk_state, &op,
562 							status);
563 				if (ACPI_FAILURE(status)) {
564 					return_ACPI_STATUS(status);
565 				}
566 
567 				continue;
568 			}
569 		}
570 
571 		/* Check for arguments that need to be processed */
572 
573 		if (walk_state->arg_count) {
574 			/*
575 			 * There are arguments (complex ones), push Op and
576 			 * prepare for argument
577 			 */
578 			status = acpi_ps_push_scope(parser_state, op,
579 						    walk_state->arg_types,
580 						    walk_state->arg_count);
581 			if (ACPI_FAILURE(status)) {
582 				status =
583 				    acpi_ps_complete_op(walk_state, &op,
584 							status);
585 				if (ACPI_FAILURE(status)) {
586 					return_ACPI_STATUS(status);
587 				}
588 
589 				continue;
590 			}
591 
592 			op = NULL;
593 			continue;
594 		}
595 
596 		/*
597 		 * All arguments have been processed -- Op is complete,
598 		 * prepare for next
599 		 */
600 		walk_state->op_info =
601 		    acpi_ps_get_opcode_info(op->common.aml_opcode);
602 		if (walk_state->op_info->flags & AML_NAMED) {
603 			if (op->common.aml_opcode == AML_REGION_OP ||
604 			    op->common.aml_opcode == AML_DATA_REGION_OP) {
605 				/*
606 				 * Skip parsing of control method or opregion body,
607 				 * because we don't have enough info in the first pass
608 				 * to parse them correctly.
609 				 *
610 				 * Completed parsing an op_region declaration, we now
611 				 * know the length.
612 				 */
613 				op->named.length =
614 				    (u32) (parser_state->aml - op->named.data);
615 			}
616 		}
617 
618 		if (walk_state->op_info->flags & AML_CREATE) {
619 			/*
620 			 * Backup to beginning of create_XXXfield declaration (1 for
621 			 * Opcode)
622 			 *
623 			 * body_length is unknown until we parse the body
624 			 */
625 			op->named.length =
626 			    (u32) (parser_state->aml - op->named.data);
627 		}
628 
629 		if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
630 			/*
631 			 * Backup to beginning of bank_field declaration
632 			 *
633 			 * body_length is unknown until we parse the body
634 			 */
635 			op->named.length =
636 			    (u32) (parser_state->aml - op->named.data);
637 		}
638 
639 		/* This op complete, notify the dispatcher */
640 
641 		if (walk_state->ascending_callback != NULL) {
642 			walk_state->op = op;
643 			walk_state->opcode = op->common.aml_opcode;
644 
645 			status = walk_state->ascending_callback(walk_state);
646 			status =
647 			    acpi_ps_next_parse_state(walk_state, op, status);
648 			if (status == AE_CTRL_PENDING) {
649 				status = AE_OK;
650 			}
651 		}
652 
653 		status = acpi_ps_complete_op(walk_state, &op, status);
654 		if (ACPI_FAILURE(status)) {
655 			return_ACPI_STATUS(status);
656 		}
657 
658 	}			/* while parser_state->Aml */
659 
660 	status = acpi_ps_complete_final_op(walk_state, op, status);
661 	return_ACPI_STATUS(status);
662 }
663