1 /******************************************************************************
2  *
3  * Module Name: psparse - Parser top level AML parse routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2004, R. Byron Moore
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 /*
46  * Parse the AML and build an operation tree as most interpreters,
47  * like Perl, do.  Parsing is done by hand rather than with a YACC
48  * generated parser to tightly constrain stack and dynamic memory
49  * usage.  At the same time, parsing is kept flexible and the code
50  * fairly compact by parsing based on a list of AML opcode
51  * templates in aml_op_info[]
52  */
53 
54 #include <acpi/acpi.h>
55 #include <acpi/acparser.h>
56 #include <acpi/acdispat.h>
57 #include <acpi/amlcode.h>
58 #include <acpi/acnamesp.h>
59 #include <acpi/acinterp.h>
60 
61 #define _COMPONENT          ACPI_PARSER
62 	 ACPI_MODULE_NAME    ("psparse")
63 
64 
65 static u32                          acpi_gbl_depth = 0;
66 
67 
68 /*******************************************************************************
69  *
70  * FUNCTION:    acpi_ps_get_opcode_size
71  *
72  * PARAMETERS:  Opcode          - An AML opcode
73  *
74  * RETURN:      Size of the opcode, in bytes (1 or 2)
75  *
76  * DESCRIPTION: Get the size of the current opcode.
77  *
78  ******************************************************************************/
79 
80 u32
acpi_ps_get_opcode_size(u32 opcode)81 acpi_ps_get_opcode_size (
82 	u32                             opcode)
83 {
84 
85 	/* Extended (2-byte) opcode if > 255 */
86 
87 	if (opcode > 0x00FF) {
88 		return (2);
89 	}
90 
91 	/* Otherwise, just a single byte opcode */
92 
93 	return (1);
94 }
95 
96 
97 /*******************************************************************************
98  *
99  * FUNCTION:    acpi_ps_peek_opcode
100  *
101  * PARAMETERS:  parser_state        - A parser state object
102  *
103  * RETURN:      Status
104  *
105  * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
106  *
107  ******************************************************************************/
108 
109 u16
acpi_ps_peek_opcode(struct acpi_parse_state * parser_state)110 acpi_ps_peek_opcode (
111 	struct acpi_parse_state         *parser_state)
112 {
113 	u8                              *aml;
114 	u16                             opcode;
115 
116 
117 	aml = parser_state->aml;
118 	opcode = (u16) ACPI_GET8 (aml);
119 
120 
121 	if (opcode == AML_EXTOP) {
122 		/* Extended opcode */
123 
124 		aml++;
125 		opcode = (u16) ((opcode << 8) | ACPI_GET8 (aml));
126 	}
127 
128 	return (opcode);
129 }
130 
131 
132 /*******************************************************************************
133  *
134  * FUNCTION:    acpi_ps_complete_this_op
135  *
136  * PARAMETERS:  walk_state      - Current State
137  *              Op              - Op to complete
138  *
139  * RETURN:      None.
140  *
141  * DESCRIPTION: Perform any cleanup at the completion of an Op.
142  *
143  ******************************************************************************/
144 
145 void
acpi_ps_complete_this_op(struct acpi_walk_state * walk_state,union acpi_parse_object * op)146 acpi_ps_complete_this_op (
147 	struct acpi_walk_state          *walk_state,
148 	union acpi_parse_object         *op)
149 {
150 	union acpi_parse_object         *prev;
151 	union acpi_parse_object         *next;
152 	const struct acpi_opcode_info   *parent_info;
153 	union acpi_parse_object         *replacement_op = NULL;
154 
155 
156 	ACPI_FUNCTION_TRACE_PTR ("ps_complete_this_op", op);
157 
158 
159 	/* Check for null Op, can happen if AML code is corrupt */
160 
161 	if (!op) {
162 		return_VOID;
163 	}
164 
165 	/* Delete this op and the subtree below it if asked to */
166 
167 	if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) == ACPI_PARSE_DELETE_TREE) &&
168 		(walk_state->op_info->class != AML_CLASS_ARGUMENT)) {
169 		/* Make sure that we only delete this subtree */
170 
171 		if (op->common.parent) {
172 			/*
173 			 * Check if we need to replace the operator and its subtree
174 			 * with a return value op (placeholder op)
175 			 */
176 			parent_info = acpi_ps_get_opcode_info (op->common.parent->common.aml_opcode);
177 
178 			switch (parent_info->class) {
179 			case AML_CLASS_CONTROL:
180 				break;
181 
182 			case AML_CLASS_CREATE:
183 
184 				/*
185 				 * These opcodes contain term_arg operands. The current
186 				 * op must be replaced by a placeholder return op
187 				 */
188 				replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
189 				if (!replacement_op) {
190 					return_VOID;
191 				}
192 				break;
193 
194 			case AML_CLASS_NAMED_OBJECT:
195 
196 				/*
197 				 * These opcodes contain term_arg operands. The current
198 				 * op must be replaced by a placeholder return op
199 				 */
200 				if ((op->common.parent->common.aml_opcode == AML_REGION_OP)      ||
201 					(op->common.parent->common.aml_opcode == AML_DATA_REGION_OP) ||
202 					(op->common.parent->common.aml_opcode == AML_BUFFER_OP)      ||
203 					(op->common.parent->common.aml_opcode == AML_PACKAGE_OP)     ||
204 					(op->common.parent->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
205 					replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
206 					if (!replacement_op) {
207 						return_VOID;
208 					}
209 				}
210 
211 				if ((op->common.parent->common.aml_opcode == AML_NAME_OP) &&
212 					(walk_state->descending_callback != acpi_ds_exec_begin_op)) {
213 					if ((op->common.aml_opcode == AML_BUFFER_OP) ||
214 						(op->common.aml_opcode == AML_PACKAGE_OP) ||
215 						(op->common.aml_opcode == AML_VAR_PACKAGE_OP)) {
216 						replacement_op = acpi_ps_alloc_op (op->common.aml_opcode);
217 						if (!replacement_op) {
218 							return_VOID;
219 						}
220 
221 						replacement_op->named.data = op->named.data;
222 						replacement_op->named.length = op->named.length;
223 					}
224 				}
225 				break;
226 
227 			default:
228 				replacement_op = acpi_ps_alloc_op (AML_INT_RETURN_VALUE_OP);
229 				if (!replacement_op) {
230 					return_VOID;
231 				}
232 			}
233 
234 			/* We must unlink this op from the parent tree */
235 
236 			prev = op->common.parent->common.value.arg;
237 			if (prev == op) {
238 				/* This op is the first in the list */
239 
240 				if (replacement_op) {
241 					replacement_op->common.parent       = op->common.parent;
242 					replacement_op->common.value.arg    = NULL;
243 					replacement_op->common.node         = op->common.node;
244 					op->common.parent->common.value.arg = replacement_op;
245 					replacement_op->common.next         = op->common.next;
246 				}
247 				else {
248 					op->common.parent->common.value.arg    = op->common.next;
249 				}
250 			}
251 
252 			/* Search the parent list */
253 
254 			else while (prev) {
255 				/* Traverse all siblings in the parent's argument list */
256 
257 				next = prev->common.next;
258 				if (next == op) {
259 					if (replacement_op) {
260 						replacement_op->common.parent   = op->common.parent;
261 						replacement_op->common.value.arg = NULL;
262 						replacement_op->common.node     = op->common.node;
263 						prev->common.next               = replacement_op;
264 						replacement_op->common.next     = op->common.next;
265 						next = NULL;
266 					}
267 					else {
268 						prev->common.next = op->common.next;
269 						next = NULL;
270 					}
271 				}
272 
273 				prev = next;
274 			}
275 		}
276 
277 		/* Now we can actually delete the subtree rooted at op */
278 
279 		acpi_ps_delete_parse_tree (op);
280 
281 		return_VOID;
282 	}
283 
284 	return_VOID;
285 }
286 
287 
288 /*******************************************************************************
289  *
290  * FUNCTION:    acpi_ps_next_parse_state
291  *
292  * PARAMETERS:  parser_state        - Current parser state object
293  *
294  * RETURN:      Status
295  *
296  * DESCRIPTION: Update the parser state based upon the return exception from
297  *              the parser callback.
298  *
299  ******************************************************************************/
300 
301 acpi_status
acpi_ps_next_parse_state(struct acpi_walk_state * walk_state,union acpi_parse_object * op,acpi_status callback_status)302 acpi_ps_next_parse_state (
303 	struct acpi_walk_state          *walk_state,
304 	union acpi_parse_object         *op,
305 	acpi_status                     callback_status)
306 {
307 	struct acpi_parse_state         *parser_state = &walk_state->parser_state;
308 	acpi_status                     status = AE_CTRL_PENDING;
309 
310 
311 	ACPI_FUNCTION_TRACE_PTR ("ps_next_parse_state", op);
312 
313 
314 	switch (callback_status) {
315 	case AE_CTRL_TERMINATE:
316 
317 		/*
318 		 * A control method was terminated via a RETURN statement.
319 		 * The walk of this method is complete.
320 		 */
321 		parser_state->aml = parser_state->aml_end;
322 		status = AE_CTRL_TERMINATE;
323 		break;
324 
325 
326 	case AE_CTRL_BREAK:
327 
328 		parser_state->aml = walk_state->aml_last_while;
329 		walk_state->control_state->common.value = FALSE;
330 		status = AE_CTRL_BREAK;
331 		break;
332 
333 	case AE_CTRL_CONTINUE:
334 
335 
336 		parser_state->aml = walk_state->aml_last_while;
337 		status = AE_CTRL_CONTINUE;
338 		break;
339 
340 	case AE_CTRL_PENDING:
341 
342 		parser_state->aml = walk_state->aml_last_while;
343 		break;
344 
345 #if 0
346 	case AE_CTRL_SKIP:
347 
348 		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
349 		status = AE_OK;
350 		break;
351 #endif
352 
353 	case AE_CTRL_TRUE:
354 
355 		/*
356 		 * Predicate of an IF was true, and we are at the matching ELSE.
357 		 * Just close out this package
358 		 */
359 		parser_state->aml = acpi_ps_get_next_package_end (parser_state);
360 		break;
361 
362 
363 	case AE_CTRL_FALSE:
364 
365 		/*
366 		 * Either an IF/WHILE Predicate was false or we encountered a BREAK
367 		 * opcode.  In both cases, we do not execute the rest of the
368 		 * package;  We simply close out the parent (finishing the walk of
369 		 * this branch of the tree) and continue execution at the parent
370 		 * level.
371 		 */
372 		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
373 
374 		/* In the case of a BREAK, just force a predicate (if any) to FALSE */
375 
376 		walk_state->control_state->common.value = FALSE;
377 		status = AE_CTRL_END;
378 		break;
379 
380 
381 	case AE_CTRL_TRANSFER:
382 
383 		/*
384 		 * A method call (invocation) -- transfer control
385 		 */
386 		status = AE_CTRL_TRANSFER;
387 		walk_state->prev_op = op;
388 		walk_state->method_call_op = op;
389 		walk_state->method_call_node = (op->common.value.arg)->common.node;
390 
391 		/* Will return value (if any) be used by the caller? */
392 
393 		walk_state->return_used = acpi_ds_is_result_used (op, walk_state);
394 		break;
395 
396 
397 	default:
398 		status = callback_status;
399 		if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
400 			status = AE_OK;
401 		}
402 		break;
403 	}
404 
405 	return_ACPI_STATUS (status);
406 }
407 
408 
409 /*******************************************************************************
410  *
411  * FUNCTION:    acpi_ps_parse_loop
412  *
413  * PARAMETERS:  parser_state        - Current parser state object
414  *
415  * RETURN:      Status
416  *
417  * DESCRIPTION: Parse AML (pointed to by the current parser state) and return
418  *              a tree of ops.
419  *
420  ******************************************************************************/
421 
422 acpi_status
acpi_ps_parse_loop(struct acpi_walk_state * walk_state)423 acpi_ps_parse_loop (
424 	struct acpi_walk_state          *walk_state)
425 {
426 	acpi_status                     status = AE_OK;
427 	union acpi_parse_object         *op = NULL;     /* current op */
428 	union acpi_parse_object         *arg = NULL;
429 	union acpi_parse_object         *pre_op = NULL;
430 	struct acpi_parse_state         *parser_state;
431 	u8                              *aml_op_start = NULL;
432 
433 
434 	ACPI_FUNCTION_TRACE_PTR ("ps_parse_loop", walk_state);
435 
436 	if (walk_state->descending_callback == NULL) {
437 		return_ACPI_STATUS (AE_BAD_PARAMETER);
438 	}
439 
440 	parser_state = &walk_state->parser_state;
441 	walk_state->arg_types = 0;
442 
443 #if (!defined (ACPI_NO_METHOD_EXECUTION) && !defined (ACPI_CONSTANT_EVAL_ONLY))
444 	if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {
445 		/* We are restarting a preempted control method */
446 
447 		if (acpi_ps_has_completed_scope (parser_state)) {
448 			/*
449 			 * We must check if a predicate to an IF or WHILE statement
450 			 * was just completed
451 			 */
452 			if ((parser_state->scope->parse_scope.op) &&
453 			   ((parser_state->scope->parse_scope.op->common.aml_opcode == AML_IF_OP) ||
454 				(parser_state->scope->parse_scope.op->common.aml_opcode == AML_WHILE_OP)) &&
455 				(walk_state->control_state) &&
456 				(walk_state->control_state->common.state ==
457 					ACPI_CONTROL_PREDICATE_EXECUTING)) {
458 				/*
459 				 * A predicate was just completed, get the value of the
460 				 * predicate and branch based on that value
461 				 */
462 				walk_state->op = NULL;
463 				status = acpi_ds_get_predicate_value (walk_state, ACPI_TO_POINTER (TRUE));
464 				if (ACPI_FAILURE (status) &&
465 					((status & AE_CODE_MASK) != AE_CODE_CONTROL)) {
466 					if (status == AE_AML_NO_RETURN_VALUE) {
467 						ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
468 							"Invoked method did not return a value, %s\n",
469 							acpi_format_exception (status)));
470 
471 					}
472 					ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "get_predicate Failed, %s\n",
473 						acpi_format_exception (status)));
474 					return_ACPI_STATUS (status);
475 				}
476 
477 				status = acpi_ps_next_parse_state (walk_state, op, status);
478 			}
479 
480 			acpi_ps_pop_scope (parser_state, &op,
481 				&walk_state->arg_types, &walk_state->arg_count);
482 			ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op));
483 		}
484 		else if (walk_state->prev_op) {
485 			/* We were in the middle of an op */
486 
487 			op = walk_state->prev_op;
488 			walk_state->arg_types = walk_state->prev_arg_types;
489 		}
490 	}
491 #endif
492 
493 	/*
494 	 * Iterative parsing loop, while there is more aml to process:
495 	 */
496 	while ((parser_state->aml < parser_state->aml_end) || (op)) {
497 		aml_op_start = parser_state->aml;
498 		if (!op) {
499 			/* Get the next opcode from the AML stream */
500 
501 			walk_state->aml_offset = (u32) ACPI_PTR_DIFF (parser_state->aml,
502 					   parser_state->aml_start);
503 			walk_state->opcode   = acpi_ps_peek_opcode (parser_state);
504 
505 			/*
506 			 * First cut to determine what we have found:
507 			 * 1) A valid AML opcode
508 			 * 2) A name string
509 			 * 3) An unknown/invalid opcode
510 			 */
511 			walk_state->op_info = acpi_ps_get_opcode_info (walk_state->opcode);
512 			switch (walk_state->op_info->class) {
513 			case AML_CLASS_ASCII:
514 			case AML_CLASS_PREFIX:
515 				/*
516 				 * Starts with a valid prefix or ASCII char, this is a name
517 				 * string.  Convert the bare name string to a namepath.
518 				 */
519 				walk_state->opcode = AML_INT_NAMEPATH_OP;
520 				walk_state->arg_types = ARGP_NAMESTRING;
521 				break;
522 
523 			case AML_CLASS_UNKNOWN:
524 
525 				/* The opcode is unrecognized.  Just skip unknown opcodes */
526 
527 				ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
528 					"Found unknown opcode %X at AML address %p offset %X, ignoring\n",
529 					walk_state->opcode, parser_state->aml, walk_state->aml_offset));
530 
531 				ACPI_DUMP_BUFFER (parser_state->aml, 128);
532 
533 				/* Assume one-byte bad opcode */
534 
535 				parser_state->aml++;
536 				continue;
537 
538 			default:
539 
540 				/* Found opcode info, this is a normal opcode */
541 
542 				parser_state->aml += acpi_ps_get_opcode_size (walk_state->opcode);
543 				walk_state->arg_types = walk_state->op_info->parse_args;
544 				break;
545 			}
546 
547 			/* Create Op structure and append to parent's argument list */
548 
549 			if (walk_state->op_info->flags & AML_NAMED) {
550 				/* Allocate a new pre_op if necessary */
551 
552 				if (!pre_op) {
553 					pre_op = acpi_ps_alloc_op (walk_state->opcode);
554 					if (!pre_op) {
555 						return_ACPI_STATUS (AE_NO_MEMORY);
556 					}
557 				}
558 
559 				pre_op->common.value.arg = NULL;
560 				pre_op->common.aml_opcode = walk_state->opcode;
561 
562 				/*
563 				 * Get and append arguments until we find the node that contains
564 				 * the name (the type ARGP_NAME).
565 				 */
566 				while (GET_CURRENT_ARG_TYPE (walk_state->arg_types) &&
567 					  (GET_CURRENT_ARG_TYPE (walk_state->arg_types) != ARGP_NAME)) {
568 					status = acpi_ps_get_next_arg (walk_state, parser_state,
569 							 GET_CURRENT_ARG_TYPE (walk_state->arg_types), &arg);
570 					if (ACPI_FAILURE (status)) {
571 						goto close_this_op;
572 					}
573 
574 					acpi_ps_append_arg (pre_op, arg);
575 					INCREMENT_ARG_LIST (walk_state->arg_types);
576 				}
577 
578 				/* Make sure that we found a NAME and didn't run out of arguments */
579 
580 				if (!GET_CURRENT_ARG_TYPE (walk_state->arg_types)) {
581 					return_ACPI_STATUS (AE_AML_NO_OPERAND);
582 				}
583 
584 				/* We know that this arg is a name, move to next arg */
585 
586 				INCREMENT_ARG_LIST (walk_state->arg_types);
587 
588 				/*
589 				 * Find the object.  This will either insert the object into
590 				 * the namespace or simply look it up
591 				 */
592 				walk_state->op = NULL;
593 
594 				status = walk_state->descending_callback (walk_state, &op);
595 				if (ACPI_FAILURE (status)) {
596 					ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "During name lookup/catalog, %s\n",
597 							acpi_format_exception (status)));
598 					goto close_this_op;
599 				}
600 
601 				if (op == NULL) {
602 					continue;
603 				}
604 
605 				status = acpi_ps_next_parse_state (walk_state, op, status);
606 				if (status == AE_CTRL_PENDING) {
607 					status = AE_OK;
608 					goto close_this_op;
609 				}
610 
611 				if (ACPI_FAILURE (status)) {
612 					goto close_this_op;
613 				}
614 
615 				acpi_ps_append_arg (op, pre_op->common.value.arg);
616 				acpi_gbl_depth++;
617 
618 				if (op->common.aml_opcode == AML_REGION_OP) {
619 					/*
620 					 * Defer final parsing of an operation_region body,
621 					 * because we don't have enough info in the first pass
622 					 * to parse it correctly (i.e., there may be method
623 					 * calls within the term_arg elements of the body.)
624 					 *
625 					 * However, we must continue parsing because
626 					 * the opregion is not a standalone package --
627 					 * we don't know where the end is at this point.
628 					 *
629 					 * (Length is unknown until parse of the body complete)
630 					 */
631 					op->named.data    = aml_op_start;
632 					op->named.length  = 0;
633 				}
634 			}
635 			else {
636 				/* Not a named opcode, just allocate Op and append to parent */
637 
638 				walk_state->op_info = acpi_ps_get_opcode_info (walk_state->opcode);
639 				op = acpi_ps_alloc_op (walk_state->opcode);
640 				if (!op) {
641 					return_ACPI_STATUS (AE_NO_MEMORY);
642 				}
643 
644 				if (walk_state->op_info->flags & AML_CREATE) {
645 					/*
646 					 * Backup to beginning of create_xXXfield declaration
647 					 * body_length is unknown until we parse the body
648 					 */
649 					op->named.data    = aml_op_start;
650 					op->named.length  = 0;
651 				}
652 
653 				acpi_ps_append_arg (acpi_ps_get_parent_scope (parser_state), op);
654 
655 				if ((walk_state->descending_callback != NULL)) {
656 					/*
657 					 * Find the object.  This will either insert the object into
658 					 * the namespace or simply look it up
659 					 */
660 					walk_state->op = op;
661 
662 					status = walk_state->descending_callback (walk_state, &op);
663 					status = acpi_ps_next_parse_state (walk_state, op, status);
664 					if (status == AE_CTRL_PENDING) {
665 						status = AE_OK;
666 						goto close_this_op;
667 					}
668 
669 					if (ACPI_FAILURE (status)) {
670 						goto close_this_op;
671 					}
672 				}
673 			}
674 
675 			op->common.aml_offset = walk_state->aml_offset;
676 
677 			if (walk_state->op_info) {
678 				ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
679 					"Opcode %4.4X [%s] Op %p Aml %p aml_offset %5.5X\n",
680 					 (u32) op->common.aml_opcode, walk_state->op_info->name,
681 					 op, parser_state->aml, op->common.aml_offset));
682 			}
683 		}
684 
685 
686 		/* Start arg_count at zero because we don't know if there are any args yet */
687 
688 		walk_state->arg_count = 0;
689 
690 		if (walk_state->arg_types) /* Are there any arguments that must be processed? */ {
691 			/* Get arguments */
692 
693 			switch (op->common.aml_opcode) {
694 			case AML_BYTE_OP:       /* AML_BYTEDATA_ARG */
695 			case AML_WORD_OP:       /* AML_WORDDATA_ARG */
696 			case AML_DWORD_OP:      /* AML_DWORDATA_ARG */
697 			case AML_QWORD_OP:      /* AML_QWORDATA_ARG */
698 			case AML_STRING_OP:     /* AML_ASCIICHARLIST_ARG */
699 
700 				/* Fill in constant or string argument directly */
701 
702 				acpi_ps_get_next_simple_arg (parser_state,
703 					GET_CURRENT_ARG_TYPE (walk_state->arg_types), op);
704 				break;
705 
706 			case AML_INT_NAMEPATH_OP:   /* AML_NAMESTRING_ARG */
707 
708 				status = acpi_ps_get_next_namepath (walk_state, parser_state, op, 1);
709 				if (ACPI_FAILURE (status)) {
710 					goto close_this_op;
711 				}
712 
713 				walk_state->arg_types = 0;
714 				break;
715 
716 			default:
717 
718 				/* Op is not a constant or string, append each argument to the Op */
719 
720 				while (GET_CURRENT_ARG_TYPE (walk_state->arg_types) &&
721 						!walk_state->arg_count) {
722 					walk_state->aml_offset = (u32) ACPI_PTR_DIFF (parser_state->aml,
723 							   parser_state->aml_start);
724 					status = acpi_ps_get_next_arg (walk_state, parser_state,
725 							 GET_CURRENT_ARG_TYPE (walk_state->arg_types), &arg);
726 					if (ACPI_FAILURE (status)) {
727 						goto close_this_op;
728 					}
729 
730 					if (arg) {
731 						arg->common.aml_offset = walk_state->aml_offset;
732 						acpi_ps_append_arg (op, arg);
733 					}
734 					INCREMENT_ARG_LIST (walk_state->arg_types);
735 				}
736 
737 				/* Special processing for certain opcodes */
738 
739 				switch (op->common.aml_opcode) {
740 				case AML_METHOD_OP:
741 
742 					/*
743 					 * Skip parsing of control method
744 					 * because we don't have enough info in the first pass
745 					 * to parse it correctly.
746 					 *
747 					 * Save the length and address of the body
748 					 */
749 					op->named.data   = parser_state->aml;
750 					op->named.length = (u32) (parser_state->pkg_end - parser_state->aml);
751 
752 					/* Skip body of method */
753 
754 					parser_state->aml   = parser_state->pkg_end;
755 					walk_state->arg_count = 0;
756 					break;
757 
758 				case AML_BUFFER_OP:
759 				case AML_PACKAGE_OP:
760 				case AML_VAR_PACKAGE_OP:
761 
762 					if ((op->common.parent) &&
763 						(op->common.parent->common.aml_opcode == AML_NAME_OP) &&
764 						(walk_state->descending_callback != acpi_ds_exec_begin_op)) {
765 						/*
766 						 * Skip parsing of Buffers and Packages
767 						 * because we don't have enough info in the first pass
768 						 * to parse them correctly.
769 						 */
770 						op->named.data   = aml_op_start;
771 						op->named.length = (u32) (parser_state->pkg_end - aml_op_start);
772 
773 						/* Skip body */
774 
775 						parser_state->aml   = parser_state->pkg_end;
776 						walk_state->arg_count = 0;
777 					}
778 					break;
779 
780 				case AML_WHILE_OP:
781 
782 					if (walk_state->control_state) {
783 						walk_state->control_state->control.package_end = parser_state->pkg_end;
784 					}
785 					break;
786 
787 				default:
788 
789 					/* No action for all other opcodes */
790 					break;
791 				}
792 				break;
793 			}
794 		}
795 
796 		/* Check for arguments that need to be processed */
797 
798 		if (walk_state->arg_count) {
799 			/* There are arguments (complex ones), push Op and prepare for argument */
800 
801 			status = acpi_ps_push_scope (parser_state, op,
802 					 walk_state->arg_types, walk_state->arg_count);
803 			if (ACPI_FAILURE (status)) {
804 				return_ACPI_STATUS (status);
805 			}
806 			op = NULL;
807 			continue;
808 		}
809 
810 		/* All arguments have been processed -- Op is complete, prepare for next */
811 
812 		walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
813 		if (walk_state->op_info->flags & AML_NAMED) {
814 			if (acpi_gbl_depth) {
815 				acpi_gbl_depth--;
816 			}
817 
818 			if (op->common.aml_opcode == AML_REGION_OP) {
819 				/*
820 				 * Skip parsing of control method or opregion body,
821 				 * because we don't have enough info in the first pass
822 				 * to parse them correctly.
823 				 *
824 				 * Completed parsing an op_region declaration, we now
825 				 * know the length.
826 				 */
827 				op->named.length = (u32) (parser_state->aml - op->named.data);
828 			}
829 		}
830 
831 		if (walk_state->op_info->flags & AML_CREATE) {
832 			/*
833 			 * Backup to beginning of create_xXXfield declaration (1 for
834 			 * Opcode)
835 			 *
836 			 * body_length is unknown until we parse the body
837 			 */
838 			op->named.length = (u32) (parser_state->aml - op->named.data);
839 		}
840 
841 		/* This op complete, notify the dispatcher */
842 
843 		if (walk_state->ascending_callback != NULL) {
844 			walk_state->op    = op;
845 			walk_state->opcode = op->common.aml_opcode;
846 
847 			status = walk_state->ascending_callback (walk_state);
848 			status = acpi_ps_next_parse_state (walk_state, op, status);
849 			if (status == AE_CTRL_PENDING) {
850 				status = AE_OK;
851 				goto close_this_op;
852 			}
853 		}
854 
855 
856 close_this_op:
857 		/*
858 		 * Finished one argument of the containing scope
859 		 */
860 		parser_state->scope->parse_scope.arg_count--;
861 
862 		/* Close this Op (will result in parse subtree deletion) */
863 
864 		acpi_ps_complete_this_op (walk_state, op);
865 		op = NULL;
866 		if (pre_op) {
867 			acpi_ps_free_op (pre_op);
868 			pre_op = NULL;
869 		}
870 
871 		switch (status) {
872 		case AE_OK:
873 			break;
874 
875 
876 		case AE_CTRL_TRANSFER:
877 
878 			/*
879 			 * We are about to transfer to a called method.
880 			 */
881 			walk_state->prev_op = op;
882 			walk_state->prev_arg_types = walk_state->arg_types;
883 			return_ACPI_STATUS (status);
884 
885 
886 		case AE_CTRL_END:
887 
888 			acpi_ps_pop_scope (parser_state, &op,
889 				&walk_state->arg_types, &walk_state->arg_count);
890 
891 			if (op) {
892 				walk_state->op    = op;
893 				walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
894 				walk_state->opcode = op->common.aml_opcode;
895 
896 				status = walk_state->ascending_callback (walk_state);
897 				status = acpi_ps_next_parse_state (walk_state, op, status);
898 
899 				acpi_ps_complete_this_op (walk_state, op);
900 				op = NULL;
901 			}
902 			status = AE_OK;
903 			break;
904 
905 
906 		case AE_CTRL_BREAK:
907 		case AE_CTRL_CONTINUE:
908 
909 			/* Pop off scopes until we find the While */
910 
911 			while (!op || (op->common.aml_opcode != AML_WHILE_OP)) {
912 				acpi_ps_pop_scope (parser_state, &op,
913 					&walk_state->arg_types, &walk_state->arg_count);
914 			}
915 
916 			/* Close this iteration of the While loop */
917 
918 			walk_state->op    = op;
919 			walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
920 			walk_state->opcode = op->common.aml_opcode;
921 
922 			status = walk_state->ascending_callback (walk_state);
923 			status = acpi_ps_next_parse_state (walk_state, op, status);
924 
925 			acpi_ps_complete_this_op (walk_state, op);
926 			op = NULL;
927 
928 			status = AE_OK;
929 			break;
930 
931 
932 		case AE_CTRL_TERMINATE:
933 
934 			status = AE_OK;
935 
936 			/* Clean up */
937 			do {
938 				if (op) {
939 					acpi_ps_complete_this_op (walk_state, op);
940 				}
941 				acpi_ps_pop_scope (parser_state, &op,
942 					&walk_state->arg_types, &walk_state->arg_count);
943 
944 			} while (op);
945 
946 			return_ACPI_STATUS (status);
947 
948 
949 		default:  /* All other non-AE_OK status */
950 
951 			do {
952 				if (op) {
953 					acpi_ps_complete_this_op (walk_state, op);
954 				}
955 				acpi_ps_pop_scope (parser_state, &op,
956 					&walk_state->arg_types, &walk_state->arg_count);
957 
958 			} while (op);
959 
960 
961 			/*
962 			 * TBD: Cleanup parse ops on error
963 			 */
964 #if 0
965 			if (op == NULL) {
966 				acpi_ps_pop_scope (parser_state, &op,
967 					&walk_state->arg_types, &walk_state->arg_count);
968 			}
969 #endif
970 			walk_state->prev_op = op;
971 			walk_state->prev_arg_types = walk_state->arg_types;
972 			return_ACPI_STATUS (status);
973 		}
974 
975 		/* This scope complete? */
976 
977 		if (acpi_ps_has_completed_scope (parser_state)) {
978 			acpi_ps_pop_scope (parser_state, &op,
979 				&walk_state->arg_types, &walk_state->arg_count);
980 			ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped scope, Op=%p\n", op));
981 		}
982 		else {
983 			op = NULL;
984 		}
985 
986 	} /* while parser_state->Aml */
987 
988 
989 	/*
990 	 * Complete the last Op (if not completed), and clear the scope stack.
991 	 * It is easily possible to end an AML "package" with an unbounded number
992 	 * of open scopes (such as when several ASL blocks are closed with
993 	 * sequential closing braces).  We want to terminate each one cleanly.
994 	 */
995 	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "AML package complete at Op %p\n", op));
996 	do {
997 		if (op) {
998 			if (walk_state->ascending_callback != NULL) {
999 				walk_state->op    = op;
1000 				walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
1001 				walk_state->opcode = op->common.aml_opcode;
1002 
1003 				status = walk_state->ascending_callback (walk_state);
1004 				status = acpi_ps_next_parse_state (walk_state, op, status);
1005 				if (status == AE_CTRL_PENDING) {
1006 					status = AE_OK;
1007 					goto close_this_op;
1008 				}
1009 
1010 				if (status == AE_CTRL_TERMINATE) {
1011 					status = AE_OK;
1012 
1013 					/* Clean up */
1014 					do {
1015 						if (op) {
1016 							acpi_ps_complete_this_op (walk_state, op);
1017 						}
1018 
1019 						acpi_ps_pop_scope (parser_state, &op,
1020 							&walk_state->arg_types, &walk_state->arg_count);
1021 
1022 					} while (op);
1023 
1024 					return_ACPI_STATUS (status);
1025 				}
1026 
1027 				else if (ACPI_FAILURE (status)) {
1028 					acpi_ps_complete_this_op (walk_state, op);
1029 					return_ACPI_STATUS (status);
1030 				}
1031 			}
1032 
1033 			acpi_ps_complete_this_op (walk_state, op);
1034 		}
1035 
1036 		acpi_ps_pop_scope (parser_state, &op, &walk_state->arg_types,
1037 			&walk_state->arg_count);
1038 
1039 	} while (op);
1040 
1041 	return_ACPI_STATUS (status);
1042 }
1043 
1044 
1045 /*******************************************************************************
1046  *
1047  * FUNCTION:    acpi_ps_parse_aml
1048  *
1049  * PARAMETERS:  start_scope     - The starting point of the parse.  Becomes the
1050  *                                root of the parsed op tree.
1051  *              Aml             - Pointer to the raw AML code to parse
1052  *              aml_size        - Length of the AML to parse
1053  *
1054  *
1055  * RETURN:      Status
1056  *
1057  * DESCRIPTION: Parse raw AML and return a tree of ops
1058  *
1059  ******************************************************************************/
1060 
1061 acpi_status
acpi_ps_parse_aml(struct acpi_walk_state * walk_state)1062 acpi_ps_parse_aml (
1063 	struct acpi_walk_state          *walk_state)
1064 {
1065 	acpi_status                     status;
1066 	acpi_status                     terminate_status;
1067 	struct acpi_thread_state        *thread;
1068 	struct acpi_thread_state        *prev_walk_list = acpi_gbl_current_walk_list;
1069 	struct acpi_walk_state          *previous_walk_state;
1070 
1071 
1072 	ACPI_FUNCTION_TRACE ("ps_parse_aml");
1073 
1074 	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Entered with walk_state=%p Aml=%p size=%X\n",
1075 		walk_state, walk_state->parser_state.aml, walk_state->parser_state.aml_size));
1076 
1077 
1078 	/* Create and initialize a new thread state */
1079 
1080 	thread = acpi_ut_create_thread_state ();
1081 	if (!thread) {
1082 		return_ACPI_STATUS (AE_NO_MEMORY);
1083 	}
1084 
1085 	walk_state->thread = thread;
1086 	acpi_ds_push_walk_state (walk_state, thread);
1087 
1088 	/*
1089 	 * This global allows the AML debugger to get a handle to the currently
1090 	 * executing control method.
1091 	 */
1092 	acpi_gbl_current_walk_list = thread;
1093 
1094 	/*
1095 	 * Execute the walk loop as long as there is a valid Walk State.  This
1096 	 * handles nested control method invocations without recursion.
1097 	 */
1098 	ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "State=%p\n", walk_state));
1099 
1100 	status = AE_OK;
1101 	while (walk_state) {
1102 		if (ACPI_SUCCESS (status)) {
1103 			/*
1104 			 * The parse_loop executes AML until the method terminates
1105 			 * or calls another method.
1106 			 */
1107 			status = acpi_ps_parse_loop (walk_state);
1108 		}
1109 
1110 		ACPI_DEBUG_PRINT ((ACPI_DB_PARSE,
1111 			"Completed one call to walk loop, %s State=%p\n",
1112 			acpi_format_exception (status), walk_state));
1113 
1114 		if (status == AE_CTRL_TRANSFER) {
1115 			/*
1116 			 * A method call was detected.
1117 			 * Transfer control to the called control method
1118 			 */
1119 			status = acpi_ds_call_control_method (thread, walk_state, NULL);
1120 
1121 			/*
1122 			 * If the transfer to the new method method call worked, a new walk
1123 			 * state was created -- get it
1124 			 */
1125 			walk_state = acpi_ds_get_current_walk_state (thread);
1126 			continue;
1127 		}
1128 		else if (status == AE_CTRL_TERMINATE) {
1129 			status = AE_OK;
1130 		}
1131 		else if (status != AE_OK) {
1132 			ACPI_REPORT_METHOD_ERROR ("Method execution failed",
1133 				walk_state->method_node, NULL, status);
1134 
1135 			/* Check for possible multi-thread reentrancy problem */
1136 
1137 			if ((status == AE_ALREADY_EXISTS) &&
1138 				(!walk_state->method_desc->method.semaphore)) {
1139 				/*
1140 				 * This method is marked not_serialized, but it tried to create a named
1141 				 * object, causing the second thread entrance to fail.  We will workaround
1142 				 * this by marking the method permanently as Serialized.
1143 				 */
1144 				walk_state->method_desc->method.method_flags |= AML_METHOD_SERIALIZED;
1145 				walk_state->method_desc->method.concurrency = 1;
1146 			}
1147 		}
1148 
1149 		if (walk_state->method_desc) {
1150 			/* Decrement the thread count on the method parse tree */
1151 
1152 			if (walk_state->method_desc->method.thread_count) {
1153 				walk_state->method_desc->method.thread_count--;
1154 			}
1155 		}
1156 
1157 		/* We are done with this walk, move on to the parent if any */
1158 
1159 		walk_state = acpi_ds_pop_walk_state (thread);
1160 
1161 		/* Reset the current scope to the beginning of scope stack */
1162 
1163 		acpi_ds_scope_stack_clear (walk_state);
1164 
1165 		/*
1166 		 * If we just returned from the execution of a control method,
1167 		 * there's lots of cleanup to do
1168 		 */
1169 		if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == ACPI_PARSE_EXECUTE) {
1170 			terminate_status = acpi_ds_terminate_control_method (walk_state);
1171 			if (ACPI_FAILURE (terminate_status)) {
1172 				ACPI_REPORT_ERROR ((
1173 					"Could not terminate control method properly\n"));
1174 
1175 				/* Ignore error and continue */
1176 			}
1177 		}
1178 
1179 		/* Delete this walk state and all linked control states */
1180 
1181 		acpi_ps_cleanup_scope (&walk_state->parser_state);
1182 
1183 		previous_walk_state = walk_state;
1184 
1185 		ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "return_value=%p, State=%p\n",
1186 			walk_state->return_desc, walk_state));
1187 
1188 		/* Check if we have restarted a preempted walk */
1189 
1190 		walk_state = acpi_ds_get_current_walk_state (thread);
1191 		if (walk_state) {
1192 			if (ACPI_SUCCESS (status)) {
1193 				/*
1194 				 * There is another walk state, restart it.
1195 				 * If the method return value is not used by the parent,
1196 				 * The object is deleted
1197 				 */
1198 				status = acpi_ds_restart_control_method (walk_state,
1199 						 previous_walk_state->return_desc);
1200 				if (ACPI_SUCCESS (status)) {
1201 					walk_state->walk_type |= ACPI_WALK_METHOD_RESTART;
1202 				}
1203 			}
1204 			else {
1205 				/* On error, delete any return object */
1206 
1207 				acpi_ut_remove_reference (previous_walk_state->return_desc);
1208 			}
1209 		}
1210 
1211 		/*
1212 		 * Just completed a 1st-level method, save the final internal return
1213 		 * value (if any)
1214 		 */
1215 		else if (previous_walk_state->caller_return_desc) {
1216 			*(previous_walk_state->caller_return_desc) = previous_walk_state->return_desc; /* NULL if no return value */
1217 		}
1218 		else if (previous_walk_state->return_desc) {
1219 			/* Caller doesn't want it, must delete it */
1220 
1221 			acpi_ut_remove_reference (previous_walk_state->return_desc);
1222 		}
1223 
1224 		acpi_ds_delete_walk_state (previous_walk_state);
1225 	}
1226 
1227 	/* Normal exit */
1228 
1229 	acpi_ex_release_all_mutexes (thread);
1230 	acpi_ut_delete_generic_state (ACPI_CAST_PTR (union acpi_generic_state, thread));
1231 	acpi_gbl_current_walk_list = prev_walk_list;
1232 	return_ACPI_STATUS (status);
1233 }
1234 
1235 
1236