1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count utilities
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2012, 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 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acinterp.h"
47 #include "acnamesp.h"
48 #include "acevents.h"
49 
50 #define _COMPONENT          ACPI_UTILITIES
51 ACPI_MODULE_NAME("utdelete")
52 
53 /* Local prototypes */
54 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object);
55 
56 static void
57 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action);
58 
59 /*******************************************************************************
60  *
61  * FUNCTION:    acpi_ut_delete_internal_obj
62  *
63  * PARAMETERS:  Object         - Object to be deleted
64  *
65  * RETURN:      None
66  *
67  * DESCRIPTION: Low level object deletion, after reference counts have been
68  *              updated (All reference counts, including sub-objects!)
69  *
70  ******************************************************************************/
71 
acpi_ut_delete_internal_obj(union acpi_operand_object * object)72 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
73 {
74 	void *obj_pointer = NULL;
75 	union acpi_operand_object *handler_desc;
76 	union acpi_operand_object *second_desc;
77 	union acpi_operand_object *next_desc;
78 	union acpi_operand_object **last_obj_ptr;
79 
80 	ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
81 
82 	if (!object) {
83 		return_VOID;
84 	}
85 
86 	/*
87 	 * Must delete or free any pointers within the object that are not
88 	 * actual ACPI objects (for example, a raw buffer pointer).
89 	 */
90 	switch (object->common.type) {
91 	case ACPI_TYPE_STRING:
92 
93 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
94 				  "**** String %p, ptr %p\n", object,
95 				  object->string.pointer));
96 
97 		/* Free the actual string buffer */
98 
99 		if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
100 
101 			/* But only if it is NOT a pointer into an ACPI table */
102 
103 			obj_pointer = object->string.pointer;
104 		}
105 		break;
106 
107 	case ACPI_TYPE_BUFFER:
108 
109 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
110 				  "**** Buffer %p, ptr %p\n", object,
111 				  object->buffer.pointer));
112 
113 		/* Free the actual buffer */
114 
115 		if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
116 
117 			/* But only if it is NOT a pointer into an ACPI table */
118 
119 			obj_pointer = object->buffer.pointer;
120 		}
121 		break;
122 
123 	case ACPI_TYPE_PACKAGE:
124 
125 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
126 				  " **** Package of count %X\n",
127 				  object->package.count));
128 
129 		/*
130 		 * Elements of the package are not handled here, they are deleted
131 		 * separately
132 		 */
133 
134 		/* Free the (variable length) element pointer array */
135 
136 		obj_pointer = object->package.elements;
137 		break;
138 
139 		/*
140 		 * These objects have a possible list of notify handlers.
141 		 * Device object also may have a GPE block.
142 		 */
143 	case ACPI_TYPE_DEVICE:
144 
145 		if (object->device.gpe_block) {
146 			(void)acpi_ev_delete_gpe_block(object->device.
147 						       gpe_block);
148 		}
149 
150 		/*lint -fallthrough */
151 
152 	case ACPI_TYPE_PROCESSOR:
153 	case ACPI_TYPE_THERMAL:
154 
155 		/* Walk the notify handler list for this object */
156 
157 		handler_desc = object->common_notify.handler;
158 		while (handler_desc) {
159 			next_desc = handler_desc->address_space.next;
160 			acpi_ut_remove_reference(handler_desc);
161 			handler_desc = next_desc;
162 		}
163 		break;
164 
165 	case ACPI_TYPE_MUTEX:
166 
167 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
168 				  "***** Mutex %p, OS Mutex %p\n",
169 				  object, object->mutex.os_mutex));
170 
171 		if (object == acpi_gbl_global_lock_mutex) {
172 
173 			/* Global Lock has extra semaphore */
174 
175 			(void)
176 			    acpi_os_delete_semaphore
177 			    (acpi_gbl_global_lock_semaphore);
178 			acpi_gbl_global_lock_semaphore = NULL;
179 
180 			acpi_os_delete_mutex(object->mutex.os_mutex);
181 			acpi_gbl_global_lock_mutex = NULL;
182 		} else {
183 			acpi_ex_unlink_mutex(object);
184 			acpi_os_delete_mutex(object->mutex.os_mutex);
185 		}
186 		break;
187 
188 	case ACPI_TYPE_EVENT:
189 
190 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
191 				  "***** Event %p, OS Semaphore %p\n",
192 				  object, object->event.os_semaphore));
193 
194 		(void)acpi_os_delete_semaphore(object->event.os_semaphore);
195 		object->event.os_semaphore = NULL;
196 		break;
197 
198 	case ACPI_TYPE_METHOD:
199 
200 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
201 				  "***** Method %p\n", object));
202 
203 		/* Delete the method mutex if it exists */
204 
205 		if (object->method.mutex) {
206 			acpi_os_delete_mutex(object->method.mutex->mutex.
207 					     os_mutex);
208 			acpi_ut_delete_object_desc(object->method.mutex);
209 			object->method.mutex = NULL;
210 		}
211 		break;
212 
213 	case ACPI_TYPE_REGION:
214 
215 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
216 				  "***** Region %p\n", object));
217 
218 		/*
219 		 * Update address_range list. However, only permanent regions
220 		 * are installed in this list. (Not created within a method)
221 		 */
222 		if (!(object->region.node->flags & ANOBJ_TEMPORARY)) {
223 			acpi_ut_remove_address_range(object->region.space_id,
224 						     object->region.node);
225 		}
226 
227 		second_desc = acpi_ns_get_secondary_object(object);
228 		if (second_desc) {
229 			/*
230 			 * Free the region_context if and only if the handler is one of the
231 			 * default handlers -- and therefore, we created the context object
232 			 * locally, it was not created by an external caller.
233 			 */
234 			handler_desc = object->region.handler;
235 			if (handler_desc) {
236 				next_desc =
237 				    handler_desc->address_space.region_list;
238 				last_obj_ptr =
239 				    &handler_desc->address_space.region_list;
240 
241 				/* Remove the region object from the handler's list */
242 
243 				while (next_desc) {
244 					if (next_desc == object) {
245 						*last_obj_ptr =
246 						    next_desc->region.next;
247 						break;
248 					}
249 
250 					/* Walk the linked list of handler */
251 
252 					last_obj_ptr = &next_desc->region.next;
253 					next_desc = next_desc->region.next;
254 				}
255 
256 				if (handler_desc->address_space.handler_flags &
257 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
258 
259 					/* Deactivate region and free region context */
260 
261 					if (handler_desc->address_space.setup) {
262 						(void)handler_desc->
263 						    address_space.setup(object,
264 									ACPI_REGION_DEACTIVATE,
265 									handler_desc->
266 									address_space.
267 									context,
268 									&second_desc->
269 									extra.
270 									region_context);
271 					}
272 				}
273 
274 				acpi_ut_remove_reference(handler_desc);
275 			}
276 
277 			/* Now we can free the Extra object */
278 
279 			acpi_ut_delete_object_desc(second_desc);
280 		}
281 		break;
282 
283 	case ACPI_TYPE_BUFFER_FIELD:
284 
285 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
286 				  "***** Buffer Field %p\n", object));
287 
288 		second_desc = acpi_ns_get_secondary_object(object);
289 		if (second_desc) {
290 			acpi_ut_delete_object_desc(second_desc);
291 		}
292 		break;
293 
294 	case ACPI_TYPE_LOCAL_BANK_FIELD:
295 
296 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
297 				  "***** Bank Field %p\n", object));
298 
299 		second_desc = acpi_ns_get_secondary_object(object);
300 		if (second_desc) {
301 			acpi_ut_delete_object_desc(second_desc);
302 		}
303 		break;
304 
305 	default:
306 		break;
307 	}
308 
309 	/* Free any allocated memory (pointer within the object) found above */
310 
311 	if (obj_pointer) {
312 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
313 				  "Deleting Object Subptr %p\n", obj_pointer));
314 		ACPI_FREE(obj_pointer);
315 	}
316 
317 	/* Now the object can be safely deleted */
318 
319 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
320 			  object, acpi_ut_get_object_type_name(object)));
321 
322 	acpi_ut_delete_object_desc(object);
323 	return_VOID;
324 }
325 
326 /*******************************************************************************
327  *
328  * FUNCTION:    acpi_ut_delete_internal_object_list
329  *
330  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
331  *
332  * RETURN:      None
333  *
334  * DESCRIPTION: This function deletes an internal object list, including both
335  *              simple objects and package objects
336  *
337  ******************************************************************************/
338 
acpi_ut_delete_internal_object_list(union acpi_operand_object ** obj_list)339 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
340 {
341 	union acpi_operand_object **internal_obj;
342 
343 	ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
344 
345 	/* Walk the null-terminated internal list */
346 
347 	for (internal_obj = obj_list; *internal_obj; internal_obj++) {
348 		acpi_ut_remove_reference(*internal_obj);
349 	}
350 
351 	/* Free the combined parameter pointer list and object array */
352 
353 	ACPI_FREE(obj_list);
354 	return_VOID;
355 }
356 
357 /*******************************************************************************
358  *
359  * FUNCTION:    acpi_ut_update_ref_count
360  *
361  * PARAMETERS:  Object          - Object whose ref count is to be updated
362  *              Action          - What to do
363  *
364  * RETURN:      New ref count
365  *
366  * DESCRIPTION: Modify the ref count and return it.
367  *
368  ******************************************************************************/
369 
370 static void
acpi_ut_update_ref_count(union acpi_operand_object * object,u32 action)371 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
372 {
373 	u16 count;
374 	u16 new_count;
375 
376 	ACPI_FUNCTION_NAME(ut_update_ref_count);
377 
378 	if (!object) {
379 		return;
380 	}
381 
382 	count = object->common.reference_count;
383 	new_count = count;
384 
385 	/*
386 	 * Perform the reference count action (increment, decrement, force delete)
387 	 */
388 	switch (action) {
389 	case REF_INCREMENT:
390 
391 		new_count++;
392 		object->common.reference_count = new_count;
393 
394 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
395 				  "Obj %p Refs=%X, [Incremented]\n",
396 				  object, new_count));
397 		break;
398 
399 	case REF_DECREMENT:
400 
401 		if (count < 1) {
402 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
403 					  "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
404 					  object, new_count));
405 
406 			new_count = 0;
407 		} else {
408 			new_count--;
409 
410 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
411 					  "Obj %p Refs=%X, [Decremented]\n",
412 					  object, new_count));
413 		}
414 
415 		if (object->common.type == ACPI_TYPE_METHOD) {
416 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
417 					  "Method Obj %p Refs=%X, [Decremented]\n",
418 					  object, new_count));
419 		}
420 
421 		object->common.reference_count = new_count;
422 		if (new_count == 0) {
423 			acpi_ut_delete_internal_obj(object);
424 		}
425 		break;
426 
427 	case REF_FORCE_DELETE:
428 
429 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
430 				  "Obj %p Refs=%X, Force delete! (Set to 0)\n",
431 				  object, count));
432 
433 		new_count = 0;
434 		object->common.reference_count = new_count;
435 		acpi_ut_delete_internal_obj(object);
436 		break;
437 
438 	default:
439 
440 		ACPI_ERROR((AE_INFO, "Unknown action (0x%X)", action));
441 		break;
442 	}
443 
444 	/*
445 	 * Sanity check the reference count, for debug purposes only.
446 	 * (A deleted object will have a huge reference count)
447 	 */
448 	if (count > ACPI_MAX_REFERENCE_COUNT) {
449 		ACPI_WARNING((AE_INFO,
450 			      "Large Reference Count (0x%X) in object %p",
451 			      count, object));
452 	}
453 }
454 
455 /*******************************************************************************
456  *
457  * FUNCTION:    acpi_ut_update_object_reference
458  *
459  * PARAMETERS:  Object              - Increment ref count for this object
460  *                                    and all sub-objects
461  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
462  *                                    REF_FORCE_DELETE
463  *
464  * RETURN:      Status
465  *
466  * DESCRIPTION: Increment the object reference count
467  *
468  * Object references are incremented when:
469  * 1) An object is attached to a Node (namespace object)
470  * 2) An object is copied (all subobjects must be incremented)
471  *
472  * Object references are decremented when:
473  * 1) An object is detached from an Node
474  *
475  ******************************************************************************/
476 
477 acpi_status
acpi_ut_update_object_reference(union acpi_operand_object * object,u16 action)478 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
479 {
480 	acpi_status status = AE_OK;
481 	union acpi_generic_state *state_list = NULL;
482 	union acpi_operand_object *next_object = NULL;
483 	union acpi_generic_state *state;
484 	u32 i;
485 
486 	ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
487 
488 	while (object) {
489 
490 		/* Make sure that this isn't a namespace handle */
491 
492 		if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
493 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
494 					  "Object %p is NS handle\n", object));
495 			return_ACPI_STATUS(AE_OK);
496 		}
497 
498 		/*
499 		 * All sub-objects must have their reference count incremented also.
500 		 * Different object types have different subobjects.
501 		 */
502 		switch (object->common.type) {
503 		case ACPI_TYPE_DEVICE:
504 		case ACPI_TYPE_PROCESSOR:
505 		case ACPI_TYPE_POWER:
506 		case ACPI_TYPE_THERMAL:
507 
508 			/* Update the notify objects for these types (if present) */
509 
510 			acpi_ut_update_ref_count(object->common_notify.
511 						 system_notify, action);
512 			acpi_ut_update_ref_count(object->common_notify.
513 						 device_notify, action);
514 			break;
515 
516 		case ACPI_TYPE_PACKAGE:
517 			/*
518 			 * We must update all the sub-objects of the package,
519 			 * each of whom may have their own sub-objects.
520 			 */
521 			for (i = 0; i < object->package.count; i++) {
522 				/*
523 				 * Push each element onto the stack for later processing.
524 				 * Note: There can be null elements within the package,
525 				 * these are simply ignored
526 				 */
527 				status =
528 				    acpi_ut_create_update_state_and_push
529 				    (object->package.elements[i], action,
530 				     &state_list);
531 				if (ACPI_FAILURE(status)) {
532 					goto error_exit;
533 				}
534 			}
535 			break;
536 
537 		case ACPI_TYPE_BUFFER_FIELD:
538 
539 			next_object = object->buffer_field.buffer_obj;
540 			break;
541 
542 		case ACPI_TYPE_LOCAL_REGION_FIELD:
543 
544 			next_object = object->field.region_obj;
545 			break;
546 
547 		case ACPI_TYPE_LOCAL_BANK_FIELD:
548 
549 			next_object = object->bank_field.bank_obj;
550 			status =
551 			    acpi_ut_create_update_state_and_push(object->
552 								 bank_field.
553 								 region_obj,
554 								 action,
555 								 &state_list);
556 			if (ACPI_FAILURE(status)) {
557 				goto error_exit;
558 			}
559 			break;
560 
561 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
562 
563 			next_object = object->index_field.index_obj;
564 			status =
565 			    acpi_ut_create_update_state_and_push(object->
566 								 index_field.
567 								 data_obj,
568 								 action,
569 								 &state_list);
570 			if (ACPI_FAILURE(status)) {
571 				goto error_exit;
572 			}
573 			break;
574 
575 		case ACPI_TYPE_LOCAL_REFERENCE:
576 			/*
577 			 * The target of an Index (a package, string, or buffer) or a named
578 			 * reference must track changes to the ref count of the index or
579 			 * target object.
580 			 */
581 			if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
582 			    (object->reference.class == ACPI_REFCLASS_NAME)) {
583 				next_object = object->reference.object;
584 			}
585 			break;
586 
587 		case ACPI_TYPE_REGION:
588 		default:
589 			break;	/* No subobjects for all other types */
590 		}
591 
592 		/*
593 		 * Now we can update the count in the main object. This can only
594 		 * happen after we update the sub-objects in case this causes the
595 		 * main object to be deleted.
596 		 */
597 		acpi_ut_update_ref_count(object, action);
598 		object = NULL;
599 
600 		/* Move on to the next object to be updated */
601 
602 		if (next_object) {
603 			object = next_object;
604 			next_object = NULL;
605 		} else if (state_list) {
606 			state = acpi_ut_pop_generic_state(&state_list);
607 			object = state->update.object;
608 			acpi_ut_delete_generic_state(state);
609 		}
610 	}
611 
612 	return_ACPI_STATUS(AE_OK);
613 
614       error_exit:
615 
616 	ACPI_EXCEPTION((AE_INFO, status,
617 			"Could not update object reference count"));
618 
619 	/* Free any stacked Update State objects */
620 
621 	while (state_list) {
622 		state = acpi_ut_pop_generic_state(&state_list);
623 		acpi_ut_delete_generic_state(state);
624 	}
625 
626 	return_ACPI_STATUS(status);
627 }
628 
629 /*******************************************************************************
630  *
631  * FUNCTION:    acpi_ut_add_reference
632  *
633  * PARAMETERS:  Object          - Object whose reference count is to be
634  *                                incremented
635  *
636  * RETURN:      None
637  *
638  * DESCRIPTION: Add one reference to an ACPI object
639  *
640  ******************************************************************************/
641 
acpi_ut_add_reference(union acpi_operand_object * object)642 void acpi_ut_add_reference(union acpi_operand_object *object)
643 {
644 
645 	ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
646 
647 	/* Ensure that we have a valid object */
648 
649 	if (!acpi_ut_valid_internal_object(object)) {
650 		return_VOID;
651 	}
652 
653 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
654 			  "Obj %p Current Refs=%X [To Be Incremented]\n",
655 			  object, object->common.reference_count));
656 
657 	/* Increment the reference count */
658 
659 	(void)acpi_ut_update_object_reference(object, REF_INCREMENT);
660 	return_VOID;
661 }
662 
663 /*******************************************************************************
664  *
665  * FUNCTION:    acpi_ut_remove_reference
666  *
667  * PARAMETERS:  Object         - Object whose ref count will be decremented
668  *
669  * RETURN:      None
670  *
671  * DESCRIPTION: Decrement the reference count of an ACPI internal object
672  *
673  ******************************************************************************/
674 
acpi_ut_remove_reference(union acpi_operand_object * object)675 void acpi_ut_remove_reference(union acpi_operand_object *object)
676 {
677 
678 	ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
679 
680 	/*
681 	 * Allow a NULL pointer to be passed in, just ignore it. This saves
682 	 * each caller from having to check. Also, ignore NS nodes.
683 	 *
684 	 */
685 	if (!object ||
686 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
687 		return_VOID;
688 	}
689 
690 	/* Ensure that we have a valid object */
691 
692 	if (!acpi_ut_valid_internal_object(object)) {
693 		return_VOID;
694 	}
695 
696 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
697 			  "Obj %p Current Refs=%X [To Be Decremented]\n",
698 			  object, object->common.reference_count));
699 
700 	/*
701 	 * Decrement the reference count, and only actually delete the object
702 	 * if the reference count becomes 0. (Must also decrement the ref count
703 	 * of all subobjects!)
704 	 */
705 	(void)acpi_ut_update_object_reference(object, REF_DECREMENT);
706 	return_VOID;
707 }
708