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v3.1
 
  1/******************************************************************************
  2 *
  3 * Module Name: psparse - Parser top level AML parse routines
  4 *
  5 *****************************************************************************/
  6
  7/*
  8 * Copyright (C) 2000 - 2011, 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
 61ACPI_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 ******************************************************************************/
 74u32 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
100u16 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
132acpi_status
133acpi_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	/* Delete this op and the subtree below it if asked to */
151
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);
156	}
157
158	/* Make sure that we only delete this subtree */
159
160	if (op->common.parent) {
161		prev = op->common.parent->common.value.arg;
162		if (!prev) {
163
164			/* Nothing more to do */
165
166			goto cleanup;
167		}
168
169		/*
170		 * Check if we need to replace the operator and its subtree
171		 * with a return value op (placeholder op)
172		 */
173		parent_info =
174		    acpi_ps_get_opcode_info(op->common.parent->common.
175					    aml_opcode);
176
177		switch (parent_info->class) {
178		case AML_CLASS_CONTROL:
 
179			break;
180
181		case AML_CLASS_CREATE:
182
183			/*
184			 * These opcodes contain term_arg operands. The current
185			 * op must be replaced by a placeholder return op
186			 */
187			replacement_op =
188			    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
 
189			if (!replacement_op) {
190				status = AE_NO_MEMORY;
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 ==
201			     AML_REGION_OP)
202			    || (op->common.parent->common.aml_opcode ==
203				AML_DATA_REGION_OP)
204			    || (op->common.parent->common.aml_opcode ==
205				AML_BUFFER_OP)
206			    || (op->common.parent->common.aml_opcode ==
207				AML_PACKAGE_OP)
208			    || (op->common.parent->common.aml_opcode ==
209				AML_BANK_FIELD_OP)
210			    || (op->common.parent->common.aml_opcode ==
211				AML_VAR_PACKAGE_OP)) {
212				replacement_op =
213				    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
 
214				if (!replacement_op) {
215					status = AE_NO_MEMORY;
216				}
217			} else
218			    if ((op->common.parent->common.aml_opcode ==
219				 AML_NAME_OP)
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)) {
226					replacement_op =
227					    acpi_ps_alloc_op(op->common.
228							     aml_opcode);
 
229					if (!replacement_op) {
230						status = AE_NO_MEMORY;
231					} else {
232						replacement_op->named.data =
233						    op->named.data;
234						replacement_op->named.length =
235						    op->named.length;
236					}
237				}
238			}
239			break;
240
241		default:
242
243			replacement_op =
244			    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP);
 
245			if (!replacement_op) {
246				status = AE_NO_MEMORY;
247			}
248		}
249
250		/* We must unlink this op from the parent tree */
251
252		if (prev == op) {
253
254			/* This op is the first in the list */
255
256			if (replacement_op) {
257				replacement_op->common.parent =
258				    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 =
262				    replacement_op;
263				replacement_op->common.next = op->common.next;
264			} else {
265				op->common.parent->common.value.arg =
266				    op->common.next;
267			}
268		}
269
270		/* Search the parent list */
271
272		else
273			while (prev) {
274
275				/* Traverse all siblings in the parent's argument list */
276
277				next = prev->common.next;
278				if (next == op) {
279					if (replacement_op) {
280						replacement_op->common.parent =
281						    op->common.parent;
282						replacement_op->common.value.
283						    arg = NULL;
284						replacement_op->common.node =
285						    op->common.node;
286						prev->common.next =
287						    replacement_op;
288						replacement_op->common.next =
289						    op->common.next;
290						next = NULL;
291					} else {
292						prev->common.next =
293						    op->common.next;
294						next = NULL;
295					}
296				}
297				prev = next;
298			}
299	}
300
301      cleanup:
302
303	/* Now we can actually delete the subtree rooted at Op */
304
305	acpi_ps_delete_parse_tree(op);
306	return_ACPI_STATUS(status);
307}
308
309/*******************************************************************************
310 *
311 * FUNCTION:    acpi_ps_next_parse_state
312 *
313 * PARAMETERS:  walk_state          - Current state
314 *              Op                  - Current parse op
315 *              callback_status     - Status from previous operation
316 *
317 * RETURN:      Status
318 *
319 * DESCRIPTION: Update the parser state based upon the return exception from
320 *              the parser callback.
321 *
322 ******************************************************************************/
323
324acpi_status
325acpi_ps_next_parse_state(struct acpi_walk_state *walk_state,
326			 union acpi_parse_object *op,
327			 acpi_status callback_status)
328{
329	struct acpi_parse_state *parser_state = &walk_state->parser_state;
330	acpi_status status = AE_CTRL_PENDING;
331
332	ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op);
333
334	switch (callback_status) {
335	case AE_CTRL_TERMINATE:
336		/*
337		 * A control method was terminated via a RETURN statement.
338		 * The walk of this method is complete.
339		 */
340		parser_state->aml = parser_state->aml_end;
341		status = AE_CTRL_TERMINATE;
342		break;
343
344	case AE_CTRL_BREAK:
345
346		parser_state->aml = walk_state->aml_last_while;
347		walk_state->control_state->common.value = FALSE;
348		status = AE_CTRL_BREAK;
349		break;
350
351	case AE_CTRL_CONTINUE:
352
353		parser_state->aml = walk_state->aml_last_while;
354		status = AE_CTRL_CONTINUE;
355		break;
356
357	case AE_CTRL_PENDING:
358
359		parser_state->aml = walk_state->aml_last_while;
360		break;
361
362#if 0
363	case AE_CTRL_SKIP:
364
365		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
366		status = AE_OK;
367		break;
368#endif
369
370	case AE_CTRL_TRUE:
371		/*
372		 * Predicate of an IF was true, and we are at the matching ELSE.
373		 * Just close out this package
374		 */
375		parser_state->aml = acpi_ps_get_next_package_end(parser_state);
376		status = AE_CTRL_PENDING;
377		break;
378
379	case AE_CTRL_FALSE:
380		/*
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
385		 * level.
386		 */
387		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
388
389		/* In the case of a BREAK, just force a predicate (if any) to FALSE */
390
391		walk_state->control_state->common.value = FALSE;
392		status = AE_CTRL_END;
393		break;
394
395	case AE_CTRL_TRANSFER:
396
397		/* A method call (invocation) -- transfer control */
398
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;
404
405		/* Will return value (if any) be used by the caller? */
406
407		walk_state->return_used =
408		    acpi_ds_is_result_used(op, walk_state);
409		break;
410
411	default:
412
413		status = callback_status;
414		if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
415			status = AE_OK;
416		}
417		break;
418	}
419
420	return_ACPI_STATUS(status);
421}
422
423/*******************************************************************************
424 *
425 * FUNCTION:    acpi_ps_parse_aml
426 *
427 * PARAMETERS:  walk_state      - Current state
428 *
429 *
430 * RETURN:      Status
431 *
432 * DESCRIPTION: Parse raw AML and return a tree of ops
433 *
434 ******************************************************************************/
435
436acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
437{
438	acpi_status status;
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;
442
443	ACPI_FUNCTION_TRACE(ps_parse_aml);
444
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));
449
450	if (!walk_state->parser_state.aml) {
451		return_ACPI_STATUS(AE_NULL_OBJECT);
452	}
453
454	/* Create and initialize a new thread state */
455
456	thread = acpi_ut_create_thread_state();
457	if (!thread) {
458		if (walk_state->method_desc) {
459
460			/* Executing a control method - additional cleanup */
461
462			acpi_ds_terminate_control_method(
463				walk_state->method_desc, walk_state);
 
464		}
465
466		acpi_ds_delete_walk_state(walk_state);
467		return_ACPI_STATUS(AE_NO_MEMORY);
468	}
469
470	walk_state->thread = thread;
471
472	/*
473	 * If executing a method, the starting sync_level is this method's
474	 * sync_level
475	 */
476	if (walk_state->method_desc) {
477		walk_state->thread->current_sync_level =
478		    walk_state->method_desc->method.sync_level;
479	}
480
481	acpi_ds_push_walk_state(walk_state, thread);
482
483	/*
484	 * This global allows the AML debugger to get a handle to the currently
485	 * executing control method.
486	 */
487	acpi_gbl_current_walk_list = thread;
488
489	/*
490	 * Execute the walk loop as long as there is a valid Walk State.  This
491	 * handles nested control method invocations without recursion.
492	 */
493	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));
494
495	status = AE_OK;
496	while (walk_state) {
497		if (ACPI_SUCCESS(status)) {
498			/*
499			 * The parse_loop executes AML until the method terminates
500			 * or calls another method.
501			 */
502			status = acpi_ps_parse_loop(walk_state);
503		}
504
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));
508
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
509		if (status == AE_CTRL_TRANSFER) {
510			/*
511			 * A method call was detected.
512			 * Transfer control to the called control method
513			 */
514			status =
515			    acpi_ds_call_control_method(thread, walk_state,
516							NULL);
517			if (ACPI_FAILURE(status)) {
518				status =
519				    acpi_ds_method_error(status, walk_state);
520			}
521
522			/*
523			 * If the transfer to the new method method call worked, a new walk
524			 * state was created -- get it
525			 */
526			walk_state = acpi_ds_get_current_walk_state(thread);
527			continue;
528		} else if (status == AE_CTRL_TERMINATE) {
529			status = AE_OK;
530		} else if ((status != AE_OK) && (walk_state->method_desc)) {
531
532			/* Either the method parse or actual execution failed */
533
534			ACPI_ERROR_METHOD("Method parse/execution failed",
535					  walk_state->method_node, NULL,
536					  status);
 
 
 
 
 
 
 
 
 
537
538			/* Check for possible multi-thread reentrancy problem */
539
540			if ((status == AE_ALREADY_EXISTS) &&
541			    (!(walk_state->method_desc->method.
542			       info_flags & ACPI_METHOD_SERIALIZED))) {
543				/*
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.
548				 */
549				walk_state->method_desc->method.info_flags |=
550				    ACPI_METHOD_SERIALIZED_PENDING;
551			}
552		}
553
554		/* We are done with this walk, move on to the parent if any */
555
556		walk_state = acpi_ds_pop_walk_state(thread);
557
558		/* Reset the current scope to the beginning of scope stack */
559
560		acpi_ds_scope_stack_clear(walk_state);
561
562		/*
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
565		 * cleanup to do
566		 */
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->
570							 method_desc,
571							 walk_state);
572		}
573
574		/* Delete this walk state and all linked control states */
575
576		acpi_ps_cleanup_scope(&walk_state->parser_state);
577		previous_walk_state = walk_state;
578
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));
583
584		/* Check if we have restarted a preempted walk */
585
586		walk_state = acpi_ds_get_current_walk_state(thread);
587		if (walk_state) {
588			if (ACPI_SUCCESS(status)) {
589				/*
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
593				 */
594				if (!previous_walk_state->return_desc) {
595					/*
596					 * In slack mode execution, if there is no return value
597					 * we should implicitly return zero (0) as a default value.
598					 */
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
605						    ((u64) 0);
606						if (!previous_walk_state->
607						    implicit_return_obj) {
608							return_ACPI_STATUS
609							    (AE_NO_MEMORY);
610						}
611					}
612
613					/* Restart the calling control method */
614
615					status =
616					    acpi_ds_restart_control_method
617					    (walk_state,
618					     previous_walk_state->
619					     implicit_return_obj);
620				} else {
621					/*
622					 * We have a valid return value, delete any implicit
623					 * return value.
624					 */
625					acpi_ds_clear_implicit_return
626					    (previous_walk_state);
627
628					status =
629					    acpi_ds_restart_control_method
630					    (walk_state,
631					     previous_walk_state->return_desc);
632				}
633				if (ACPI_SUCCESS(status)) {
634					walk_state->walk_type |=
635					    ACPI_WALK_METHOD_RESTART;
636				}
637			} else {
638				/* On error, delete any return object or implicit return */
639
640				acpi_ut_remove_reference(previous_walk_state->
641							 return_desc);
642				acpi_ds_clear_implicit_return
643				    (previous_walk_state);
644			}
645		}
646
647		/*
648		 * Just completed a 1st-level method, save the final internal return
649		 * value (if any)
650		 */
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;
655			} else {
656				/* NULL if no return value */
657
658				*(previous_walk_state->caller_return_desc) =
659				    previous_walk_state->return_desc;
660			}
661		} else {
662			if (previous_walk_state->return_desc) {
663
664				/* Caller doesn't want it, must delete it */
665
666				acpi_ut_remove_reference(previous_walk_state->
667							 return_desc);
668			}
669			if (previous_walk_state->implicit_return_obj) {
670
671				/* Caller doesn't want it, must delete it */
672
673				acpi_ut_remove_reference(previous_walk_state->
674							 implicit_return_obj);
675			}
676		}
677
678		acpi_ds_delete_walk_state(previous_walk_state);
679	}
680
681	/* Normal exit */
682
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);
688}
v5.4
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/******************************************************************************
  3 *
  4 * Module Name: psparse - Parser top level AML parse routines
  5 *
  6 * Copyright (C) 2000 - 2019, Intel Corp.
 
 
 
 
  7 *
  8 *****************************************************************************/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9
 10/*
 11 * Parse the AML and build an operation tree as most interpreters,
 12 * like Perl, do. Parsing is done by hand rather than with a YACC
 13 * generated parser to tightly constrain stack and dynamic memory
 14 * usage. At the same time, parsing is kept flexible and the code
 15 * fairly compact by parsing based on a list of AML opcode
 16 * templates in aml_op_info[]
 17 */
 18
 19#include <acpi/acpi.h>
 20#include "accommon.h"
 21#include "acparser.h"
 22#include "acdispat.h"
 23#include "amlcode.h"
 24#include "acinterp.h"
 25#include "acnamesp.h"
 26
 27#define _COMPONENT          ACPI_PARSER
 28ACPI_MODULE_NAME("psparse")
 29
 30/*******************************************************************************
 31 *
 32 * FUNCTION:    acpi_ps_get_opcode_size
 33 *
 34 * PARAMETERS:  opcode          - An AML opcode
 35 *
 36 * RETURN:      Size of the opcode, in bytes (1 or 2)
 37 *
 38 * DESCRIPTION: Get the size of the current opcode.
 39 *
 40 ******************************************************************************/
 41u32 acpi_ps_get_opcode_size(u32 opcode)
 42{
 43
 44	/* Extended (2-byte) opcode if > 255 */
 45
 46	if (opcode > 0x00FF) {
 47		return (2);
 48	}
 49
 50	/* Otherwise, just a single byte opcode */
 51
 52	return (1);
 53}
 54
 55/*******************************************************************************
 56 *
 57 * FUNCTION:    acpi_ps_peek_opcode
 58 *
 59 * PARAMETERS:  parser_state        - A parser state object
 60 *
 61 * RETURN:      Next AML opcode
 62 *
 63 * DESCRIPTION: Get next AML opcode (without incrementing AML pointer)
 64 *
 65 ******************************************************************************/
 66
 67u16 acpi_ps_peek_opcode(struct acpi_parse_state * parser_state)
 68{
 69	u8 *aml;
 70	u16 opcode;
 71
 72	aml = parser_state->aml;
 73	opcode = (u16) ACPI_GET8(aml);
 74
 75	if (opcode == AML_EXTENDED_PREFIX) {
 76
 77		/* Extended opcode, get the second opcode byte */
 78
 79		aml++;
 80		opcode = (u16) ((opcode << 8) | ACPI_GET8(aml));
 81	}
 82
 83	return (opcode);
 84}
 85
 86/*******************************************************************************
 87 *
 88 * FUNCTION:    acpi_ps_complete_this_op
 89 *
 90 * PARAMETERS:  walk_state      - Current State
 91 *              op              - Op to complete
 92 *
 93 * RETURN:      Status
 94 *
 95 * DESCRIPTION: Perform any cleanup at the completion of an Op.
 96 *
 97 ******************************************************************************/
 98
 99acpi_status
100acpi_ps_complete_this_op(struct acpi_walk_state *walk_state,
101			 union acpi_parse_object *op)
102{
103	union acpi_parse_object *prev;
104	union acpi_parse_object *next;
105	const struct acpi_opcode_info *parent_info;
106	union acpi_parse_object *replacement_op = NULL;
107	acpi_status status = AE_OK;
108
109	ACPI_FUNCTION_TRACE_PTR(ps_complete_this_op, op);
110
111	/* Check for null Op, can happen if AML code is corrupt */
112
113	if (!op) {
114		return_ACPI_STATUS(AE_OK);	/* OK for now */
115	}
116
117	acpi_ex_stop_trace_opcode(op, walk_state);
118
119	/* Delete this op and the subtree below it if asked to */
120
121	if (((walk_state->parse_flags & ACPI_PARSE_TREE_MASK) !=
122	     ACPI_PARSE_DELETE_TREE)
123	    || (walk_state->op_info->class == AML_CLASS_ARGUMENT)) {
124		return_ACPI_STATUS(AE_OK);
125	}
126
127	/* Make sure that we only delete this subtree */
128
129	if (op->common.parent) {
130		prev = op->common.parent->common.value.arg;
131		if (!prev) {
132
133			/* Nothing more to do */
134
135			goto cleanup;
136		}
137
138		/*
139		 * Check if we need to replace the operator and its subtree
140		 * with a return value op (placeholder op)
141		 */
142		parent_info =
143		    acpi_ps_get_opcode_info(op->common.parent->common.
144					    aml_opcode);
145
146		switch (parent_info->class) {
147		case AML_CLASS_CONTROL:
148
149			break;
150
151		case AML_CLASS_CREATE:
 
152			/*
153			 * These opcodes contain term_arg operands. The current
154			 * op must be replaced by a placeholder return op
155			 */
156			replacement_op =
157			    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP,
158					     op->common.aml);
159			if (!replacement_op) {
160				status = AE_NO_MEMORY;
161			}
162			break;
163
164		case AML_CLASS_NAMED_OBJECT:
 
165			/*
166			 * These opcodes contain term_arg operands. The current
167			 * op must be replaced by a placeholder return op
168			 */
169			if ((op->common.parent->common.aml_opcode ==
170			     AML_REGION_OP)
171			    || (op->common.parent->common.aml_opcode ==
172				AML_DATA_REGION_OP)
173			    || (op->common.parent->common.aml_opcode ==
174				AML_BUFFER_OP)
175			    || (op->common.parent->common.aml_opcode ==
176				AML_PACKAGE_OP)
177			    || (op->common.parent->common.aml_opcode ==
178				AML_BANK_FIELD_OP)
179			    || (op->common.parent->common.aml_opcode ==
180				AML_VARIABLE_PACKAGE_OP)) {
181				replacement_op =
182				    acpi_ps_alloc_op(AML_INT_RETURN_VALUE_OP,
183						     op->common.aml);
184				if (!replacement_op) {
185					status = AE_NO_MEMORY;
186				}
187			} else
188			    if ((op->common.parent->common.aml_opcode ==
189				 AML_NAME_OP)
190				&& (walk_state->pass_number <=
191				    ACPI_IMODE_LOAD_PASS2)) {
192				if ((op->common.aml_opcode == AML_BUFFER_OP)
193				    || (op->common.aml_opcode == AML_PACKAGE_OP)
194				    || (op->common.aml_opcode ==
195					AML_VARIABLE_PACKAGE_OP)) {
196					replacement_op =
197					    acpi_ps_alloc_op(op->common.
198							     aml_opcode,
199							     op->common.aml);
200					if (!replacement_op) {
201						status = AE_NO_MEMORY;
202					} else {
203						replacement_op->named.data =
204						    op->named.data;
205						replacement_op->named.length =
206						    op->named.length;
207					}
208				}
209			}
210			break;
211
212		default:
213
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		}
221
222		/* We must unlink this op from the parent tree */
223
224		if (prev == op) {
225
226			/* This op is the first in the list */
227
228			if (replacement_op) {
229				replacement_op->common.parent =
230				    op->common.parent;
231				replacement_op->common.value.arg = NULL;
232				replacement_op->common.node = op->common.node;
233				op->common.parent->common.value.arg =
234				    replacement_op;
235				replacement_op->common.next = op->common.next;
236			} else {
237				op->common.parent->common.value.arg =
238				    op->common.next;
239			}
240		}
241
242		/* Search the parent list */
243
244		else
245			while (prev) {
246
247				/* Traverse all siblings in the parent's argument list */
248
249				next = prev->common.next;
250				if (next == op) {
251					if (replacement_op) {
252						replacement_op->common.parent =
253						    op->common.parent;
254						replacement_op->common.value.
255						    arg = NULL;
256						replacement_op->common.node =
257						    op->common.node;
258						prev->common.next =
259						    replacement_op;
260						replacement_op->common.next =
261						    op->common.next;
262						next = NULL;
263					} else {
264						prev->common.next =
265						    op->common.next;
266						next = NULL;
267					}
268				}
269				prev = next;
270			}
271	}
272
273cleanup:
274
275	/* Now we can actually delete the subtree rooted at Op */
276
277	acpi_ps_delete_parse_tree(op);
278	return_ACPI_STATUS(status);
279}
280
281/*******************************************************************************
282 *
283 * FUNCTION:    acpi_ps_next_parse_state
284 *
285 * PARAMETERS:  walk_state          - Current state
286 *              op                  - Current parse op
287 *              callback_status     - Status from previous operation
288 *
289 * RETURN:      Status
290 *
291 * DESCRIPTION: Update the parser state based upon the return exception from
292 *              the parser callback.
293 *
294 ******************************************************************************/
295
296acpi_status
297acpi_ps_next_parse_state(struct acpi_walk_state *walk_state,
298			 union acpi_parse_object *op,
299			 acpi_status callback_status)
300{
301	struct acpi_parse_state *parser_state = &walk_state->parser_state;
302	acpi_status status = AE_CTRL_PENDING;
303
304	ACPI_FUNCTION_TRACE_PTR(ps_next_parse_state, op);
305
306	switch (callback_status) {
307	case AE_CTRL_TERMINATE:
308		/*
309		 * A control method was terminated via a RETURN statement.
310		 * The walk of this method is complete.
311		 */
312		parser_state->aml = parser_state->aml_end;
313		status = AE_CTRL_TERMINATE;
314		break;
315
316	case AE_CTRL_BREAK:
317
318		parser_state->aml = walk_state->aml_last_while;
319		walk_state->control_state->common.value = FALSE;
320		status = AE_CTRL_BREAK;
321		break;
322
323	case AE_CTRL_CONTINUE:
324
325		parser_state->aml = walk_state->aml_last_while;
326		status = AE_CTRL_CONTINUE;
327		break;
328
329	case AE_CTRL_PENDING:
330
331		parser_state->aml = walk_state->aml_last_while;
332		break;
333
334#if 0
335	case AE_CTRL_SKIP:
336
337		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
338		status = AE_OK;
339		break;
340#endif
341
342	case AE_CTRL_TRUE:
343		/*
344		 * Predicate of an IF was true, and we are at the matching ELSE.
345		 * Just close out this package
346		 */
347		parser_state->aml = acpi_ps_get_next_package_end(parser_state);
348		status = AE_CTRL_PENDING;
349		break;
350
351	case AE_CTRL_FALSE:
352		/*
353		 * Either an IF/WHILE Predicate was false or we encountered a BREAK
354		 * opcode. In both cases, we do not execute the rest of the
355		 * package;  We simply close out the parent (finishing the walk of
356		 * this branch of the tree) and continue execution at the parent
357		 * level.
358		 */
359		parser_state->aml = parser_state->scope->parse_scope.pkg_end;
360
361		/* In the case of a BREAK, just force a predicate (if any) to FALSE */
362
363		walk_state->control_state->common.value = FALSE;
364		status = AE_CTRL_END;
365		break;
366
367	case AE_CTRL_TRANSFER:
368
369		/* A method call (invocation) -- transfer control */
370
371		status = AE_CTRL_TRANSFER;
372		walk_state->prev_op = op;
373		walk_state->method_call_op = op;
374		walk_state->method_call_node =
375		    (op->common.value.arg)->common.node;
376
377		/* Will return value (if any) be used by the caller? */
378
379		walk_state->return_used =
380		    acpi_ds_is_result_used(op, walk_state);
381		break;
382
383	default:
384
385		status = callback_status;
386		if ((callback_status & AE_CODE_MASK) == AE_CODE_CONTROL) {
387			status = AE_OK;
388		}
389		break;
390	}
391
392	return_ACPI_STATUS(status);
393}
394
395/*******************************************************************************
396 *
397 * FUNCTION:    acpi_ps_parse_aml
398 *
399 * PARAMETERS:  walk_state      - Current state
400 *
401 *
402 * RETURN:      Status
403 *
404 * DESCRIPTION: Parse raw AML and return a tree of ops
405 *
406 ******************************************************************************/
407
408acpi_status acpi_ps_parse_aml(struct acpi_walk_state *walk_state)
409{
410	acpi_status status;
411	struct acpi_thread_state *thread;
412	struct acpi_thread_state *prev_walk_list = acpi_gbl_current_walk_list;
413	struct acpi_walk_state *previous_walk_state;
414
415	ACPI_FUNCTION_TRACE(ps_parse_aml);
416
417	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
418			  "Entered with WalkState=%p Aml=%p size=%X\n",
419			  walk_state, walk_state->parser_state.aml,
420			  walk_state->parser_state.aml_size));
421
422	if (!walk_state->parser_state.aml) {
423		return_ACPI_STATUS(AE_BAD_ADDRESS);
424	}
425
426	/* Create and initialize a new thread state */
427
428	thread = acpi_ut_create_thread_state();
429	if (!thread) {
430		if (walk_state->method_desc) {
431
432			/* Executing a control method - additional cleanup */
433
434			acpi_ds_terminate_control_method(walk_state->
435							 method_desc,
436							 walk_state);
437		}
438
439		acpi_ds_delete_walk_state(walk_state);
440		return_ACPI_STATUS(AE_NO_MEMORY);
441	}
442
443	walk_state->thread = thread;
444
445	/*
446	 * If executing a method, the starting sync_level is this method's
447	 * sync_level
448	 */
449	if (walk_state->method_desc) {
450		walk_state->thread->current_sync_level =
451		    walk_state->method_desc->method.sync_level;
452	}
453
454	acpi_ds_push_walk_state(walk_state, thread);
455
456	/*
457	 * This global allows the AML debugger to get a handle to the currently
458	 * executing control method.
459	 */
460	acpi_gbl_current_walk_list = thread;
461
462	/*
463	 * Execute the walk loop as long as there is a valid Walk State. This
464	 * handles nested control method invocations without recursion.
465	 */
466	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "State=%p\n", walk_state));
467
468	status = AE_OK;
469	while (walk_state) {
470		if (ACPI_SUCCESS(status)) {
471			/*
472			 * The parse_loop executes AML until the method terminates
473			 * or calls another method.
474			 */
475			status = acpi_ps_parse_loop(walk_state);
476		}
477
478		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
479				  "Completed one call to walk loop, %s State=%p\n",
480				  acpi_format_exception(status), walk_state));
481
482		if (walk_state->method_pathname && walk_state->method_is_nested) {
483
484			/* Optional object evaluation log */
485
486			ACPI_DEBUG_PRINT_RAW((ACPI_DB_EVALUATION,
487					      "%-26s:  %*s%s\n",
488					      "   Exit nested method",
489					      (walk_state->
490					       method_nesting_depth + 1) * 3,
491					      " ",
492					      &walk_state->method_pathname[1]));
493
494			ACPI_FREE(walk_state->method_pathname);
495			walk_state->method_is_nested = FALSE;
496		}
497		if (status == AE_CTRL_TRANSFER) {
498			/*
499			 * A method call was detected.
500			 * Transfer control to the called control method
501			 */
502			status =
503			    acpi_ds_call_control_method(thread, walk_state,
504							NULL);
505			if (ACPI_FAILURE(status)) {
506				status =
507				    acpi_ds_method_error(status, walk_state);
508			}
509
510			/*
511			 * If the transfer to the new method method call worked
512			 *, a new walk state was created -- get it
513			 */
514			walk_state = acpi_ds_get_current_walk_state(thread);
515			continue;
516		} else if (status == AE_CTRL_TERMINATE) {
517			status = AE_OK;
518		} else if ((status != AE_OK) && (walk_state->method_desc)) {
519
520			/* Either the method parse or actual execution failed */
521
522			acpi_ex_exit_interpreter();
523			if (status == AE_ABORT_METHOD) {
524				acpi_ns_print_node_pathname(walk_state->
525							    method_node,
526							    "Aborting method");
527				acpi_os_printf("\n");
528			} else {
529				ACPI_ERROR_METHOD("Aborting method",
530						  walk_state->method_node, NULL,
531						  status);
532			}
533			acpi_ex_enter_interpreter();
534
535			/* Check for possible multi-thread reentrancy problem */
536
537			if ((status == AE_ALREADY_EXISTS) &&
538			    (!(walk_state->method_desc->method.info_flags &
539			       ACPI_METHOD_SERIALIZED))) {
540				/*
541				 * Method is not serialized and tried to create an object
542				 * twice. The probable cause is that the method cannot
543				 * handle reentrancy. Mark as "pending serialized" now, and
544				 * then mark "serialized" when the last thread exits.
545				 */
546				walk_state->method_desc->method.info_flags |=
547				    ACPI_METHOD_SERIALIZED_PENDING;
548			}
549		}
550
551		/* We are done with this walk, move on to the parent if any */
552
553		walk_state = acpi_ds_pop_walk_state(thread);
554
555		/* Reset the current scope to the beginning of scope stack */
556
557		acpi_ds_scope_stack_clear(walk_state);
558
559		/*
560		 * If we just returned from the execution of a control method or if we
561		 * encountered an error during the method parse phase, there's lots of
562		 * cleanup to do
563		 */
564		if (((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) ==
565		     ACPI_PARSE_EXECUTE &&
566		     !(walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL)) ||
567		    (ACPI_FAILURE(status))) {
568			acpi_ds_terminate_control_method(walk_state->
569							 method_desc,
570							 walk_state);
571		}
572
573		/* Delete this walk state and all linked control states */
574
575		acpi_ps_cleanup_scope(&walk_state->parser_state);
576		previous_walk_state = walk_state;
577
578		ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
579				  "ReturnValue=%p, ImplicitValue=%p State=%p\n",
580				  walk_state->return_desc,
581				  walk_state->implicit_return_obj, walk_state));
582
583		/* Check if we have restarted a preempted walk */
584
585		walk_state = acpi_ds_get_current_walk_state(thread);
586		if (walk_state) {
587			if (ACPI_SUCCESS(status)) {
588				/*
589				 * There is another walk state, restart it.
590				 * If the method return value is not used by the parent,
591				 * The object is deleted
592				 */
593				if (!previous_walk_state->return_desc) {
594					/*
595					 * In slack mode execution, if there is no return value
596					 * we should implicitly return zero (0) as a default value.
597					 */
598					if (acpi_gbl_enable_interpreter_slack &&
599					    !previous_walk_state->
600					    implicit_return_obj) {
601						previous_walk_state->
602						    implicit_return_obj =
603						    acpi_ut_create_integer_object
604						    ((u64) 0);
605						if (!previous_walk_state->
606						    implicit_return_obj) {
607							return_ACPI_STATUS
608							    (AE_NO_MEMORY);
609						}
610					}
611
612					/* Restart the calling control method */
613
614					status =
615					    acpi_ds_restart_control_method
616					    (walk_state,
617					     previous_walk_state->
618					     implicit_return_obj);
619				} else {
620					/*
621					 * We have a valid return value, delete any implicit
622					 * return value.
623					 */
624					acpi_ds_clear_implicit_return
625					    (previous_walk_state);
626
627					status =
628					    acpi_ds_restart_control_method
629					    (walk_state,
630					     previous_walk_state->return_desc);
631				}
632				if (ACPI_SUCCESS(status)) {
633					walk_state->walk_type |=
634					    ACPI_WALK_METHOD_RESTART;
635				}
636			} else {
637				/* On error, delete any return object or implicit return */
638
639				acpi_ut_remove_reference(previous_walk_state->
640							 return_desc);
641				acpi_ds_clear_implicit_return
642				    (previous_walk_state);
643			}
644		}
645
646		/*
647		 * Just completed a 1st-level method, save the final internal return
648		 * value (if any)
649		 */
650		else if (previous_walk_state->caller_return_desc) {
651			if (previous_walk_state->implicit_return_obj) {
652				*(previous_walk_state->caller_return_desc) =
653				    previous_walk_state->implicit_return_obj;
654			} else {
655				/* NULL if no return value */
656
657				*(previous_walk_state->caller_return_desc) =
658				    previous_walk_state->return_desc;
659			}
660		} else {
661			if (previous_walk_state->return_desc) {
662
663				/* Caller doesn't want it, must delete it */
664
665				acpi_ut_remove_reference(previous_walk_state->
666							 return_desc);
667			}
668			if (previous_walk_state->implicit_return_obj) {
669
670				/* Caller doesn't want it, must delete it */
671
672				acpi_ut_remove_reference(previous_walk_state->
673							 implicit_return_obj);
674			}
675		}
676
677		acpi_ds_delete_walk_state(previous_walk_state);
678	}
679
680	/* Normal exit */
681
682	acpi_ex_release_all_mutexes(thread);
683	acpi_ut_delete_generic_state(ACPI_CAST_PTR
684				     (union acpi_generic_state, thread));
685	acpi_gbl_current_walk_list = prev_walk_list;
686	return_ACPI_STATUS(status);
687}