1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count utilities
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 #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 		/* Invalidate the region address/length via the host OS */
219 
220 		acpi_os_invalidate_address(object->region.space_id,
221 					  object->region.address,
222 					  (acpi_size) object->region.length);
223 
224 		second_desc = acpi_ns_get_secondary_object(object);
225 		if (second_desc) {
226 			/*
227 			 * Free the region_context if and only if the handler is one of the
228 			 * default handlers -- and therefore, we created the context object
229 			 * locally, it was not created by an external caller.
230 			 */
231 			handler_desc = object->region.handler;
232 			if (handler_desc) {
233 				next_desc =
234 				    handler_desc->address_space.region_list;
235 				last_obj_ptr =
236 				    &handler_desc->address_space.region_list;
237 
238 				/* Remove the region object from the handler's list */
239 
240 				while (next_desc) {
241 					if (next_desc == object) {
242 						*last_obj_ptr =
243 						    next_desc->region.next;
244 						break;
245 					}
246 
247 					/* Walk the linked list of handler */
248 
249 					last_obj_ptr = &next_desc->region.next;
250 					next_desc = next_desc->region.next;
251 				}
252 
253 				if (handler_desc->address_space.handler_flags &
254 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
255 
256 					/* Deactivate region and free region context */
257 
258 					if (handler_desc->address_space.setup) {
259 						(void)handler_desc->
260 						    address_space.setup(object,
261 									ACPI_REGION_DEACTIVATE,
262 									handler_desc->
263 									address_space.
264 									context,
265 									&second_desc->
266 									extra.
267 									region_context);
268 					}
269 				}
270 
271 				acpi_ut_remove_reference(handler_desc);
272 			}
273 
274 			/* Now we can free the Extra object */
275 
276 			acpi_ut_delete_object_desc(second_desc);
277 		}
278 		break;
279 
280 	case ACPI_TYPE_BUFFER_FIELD:
281 
282 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
283 				  "***** Buffer Field %p\n", object));
284 
285 		second_desc = acpi_ns_get_secondary_object(object);
286 		if (second_desc) {
287 			acpi_ut_delete_object_desc(second_desc);
288 		}
289 		break;
290 
291 	case ACPI_TYPE_LOCAL_BANK_FIELD:
292 
293 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
294 				  "***** Bank Field %p\n", object));
295 
296 		second_desc = acpi_ns_get_secondary_object(object);
297 		if (second_desc) {
298 			acpi_ut_delete_object_desc(second_desc);
299 		}
300 		break;
301 
302 	default:
303 		break;
304 	}
305 
306 	/* Free any allocated memory (pointer within the object) found above */
307 
308 	if (obj_pointer) {
309 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
310 				  "Deleting Object Subptr %p\n", obj_pointer));
311 		ACPI_FREE(obj_pointer);
312 	}
313 
314 	/* Now the object can be safely deleted */
315 
316 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
317 			  object, acpi_ut_get_object_type_name(object)));
318 
319 	acpi_ut_delete_object_desc(object);
320 	return_VOID;
321 }
322 
323 /*******************************************************************************
324  *
325  * FUNCTION:    acpi_ut_delete_internal_object_list
326  *
327  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
328  *
329  * RETURN:      None
330  *
331  * DESCRIPTION: This function deletes an internal object list, including both
332  *              simple objects and package objects
333  *
334  ******************************************************************************/
335 
acpi_ut_delete_internal_object_list(union acpi_operand_object ** obj_list)336 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
337 {
338 	union acpi_operand_object **internal_obj;
339 
340 	ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
341 
342 	/* Walk the null-terminated internal list */
343 
344 	for (internal_obj = obj_list; *internal_obj; internal_obj++) {
345 		acpi_ut_remove_reference(*internal_obj);
346 	}
347 
348 	/* Free the combined parameter pointer list and object array */
349 
350 	ACPI_FREE(obj_list);
351 	return_VOID;
352 }
353 
354 /*******************************************************************************
355  *
356  * FUNCTION:    acpi_ut_update_ref_count
357  *
358  * PARAMETERS:  Object          - Object whose ref count is to be updated
359  *              Action          - What to do
360  *
361  * RETURN:      New ref count
362  *
363  * DESCRIPTION: Modify the ref count and return it.
364  *
365  ******************************************************************************/
366 
367 static void
acpi_ut_update_ref_count(union acpi_operand_object * object,u32 action)368 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
369 {
370 	u16 count;
371 	u16 new_count;
372 
373 	ACPI_FUNCTION_NAME(ut_update_ref_count);
374 
375 	if (!object) {
376 		return;
377 	}
378 
379 	count = object->common.reference_count;
380 	new_count = count;
381 
382 	/*
383 	 * Perform the reference count action (increment, decrement, force delete)
384 	 */
385 	switch (action) {
386 	case REF_INCREMENT:
387 
388 		new_count++;
389 		object->common.reference_count = new_count;
390 
391 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
392 				  "Obj %p Refs=%X, [Incremented]\n",
393 				  object, new_count));
394 		break;
395 
396 	case REF_DECREMENT:
397 
398 		if (count < 1) {
399 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
400 					  "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
401 					  object, new_count));
402 
403 			new_count = 0;
404 		} else {
405 			new_count--;
406 
407 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
408 					  "Obj %p Refs=%X, [Decremented]\n",
409 					  object, new_count));
410 		}
411 
412 		if (object->common.type == ACPI_TYPE_METHOD) {
413 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
414 					  "Method Obj %p Refs=%X, [Decremented]\n",
415 					  object, new_count));
416 		}
417 
418 		object->common.reference_count = new_count;
419 		if (new_count == 0) {
420 			acpi_ut_delete_internal_obj(object);
421 		}
422 		break;
423 
424 	case REF_FORCE_DELETE:
425 
426 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
427 				  "Obj %p Refs=%X, Force delete! (Set to 0)\n",
428 				  object, count));
429 
430 		new_count = 0;
431 		object->common.reference_count = new_count;
432 		acpi_ut_delete_internal_obj(object);
433 		break;
434 
435 	default:
436 
437 		ACPI_ERROR((AE_INFO, "Unknown action (0x%X)", action));
438 		break;
439 	}
440 
441 	/*
442 	 * Sanity check the reference count, for debug purposes only.
443 	 * (A deleted object will have a huge reference count)
444 	 */
445 	if (count > ACPI_MAX_REFERENCE_COUNT) {
446 		ACPI_WARNING((AE_INFO,
447 			      "Large Reference Count (0x%X) in object %p",
448 			      count, object));
449 	}
450 }
451 
452 /*******************************************************************************
453  *
454  * FUNCTION:    acpi_ut_update_object_reference
455  *
456  * PARAMETERS:  Object              - Increment ref count for this object
457  *                                    and all sub-objects
458  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
459  *                                    REF_FORCE_DELETE
460  *
461  * RETURN:      Status
462  *
463  * DESCRIPTION: Increment the object reference count
464  *
465  * Object references are incremented when:
466  * 1) An object is attached to a Node (namespace object)
467  * 2) An object is copied (all subobjects must be incremented)
468  *
469  * Object references are decremented when:
470  * 1) An object is detached from an Node
471  *
472  ******************************************************************************/
473 
474 acpi_status
acpi_ut_update_object_reference(union acpi_operand_object * object,u16 action)475 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
476 {
477 	acpi_status status = AE_OK;
478 	union acpi_generic_state *state_list = NULL;
479 	union acpi_operand_object *next_object = NULL;
480 	union acpi_generic_state *state;
481 	u32 i;
482 
483 	ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
484 
485 	while (object) {
486 
487 		/* Make sure that this isn't a namespace handle */
488 
489 		if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
490 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
491 					  "Object %p is NS handle\n", object));
492 			return_ACPI_STATUS(AE_OK);
493 		}
494 
495 		/*
496 		 * All sub-objects must have their reference count incremented also.
497 		 * Different object types have different subobjects.
498 		 */
499 		switch (object->common.type) {
500 		case ACPI_TYPE_DEVICE:
501 		case ACPI_TYPE_PROCESSOR:
502 		case ACPI_TYPE_POWER:
503 		case ACPI_TYPE_THERMAL:
504 
505 			/* Update the notify objects for these types (if present) */
506 
507 			acpi_ut_update_ref_count(object->common_notify.
508 						 system_notify, action);
509 			acpi_ut_update_ref_count(object->common_notify.
510 						 device_notify, action);
511 			break;
512 
513 		case ACPI_TYPE_PACKAGE:
514 			/*
515 			 * We must update all the sub-objects of the package,
516 			 * each of whom may have their own sub-objects.
517 			 */
518 			for (i = 0; i < object->package.count; i++) {
519 				/*
520 				 * Push each element onto the stack for later processing.
521 				 * Note: There can be null elements within the package,
522 				 * these are simply ignored
523 				 */
524 				status =
525 				    acpi_ut_create_update_state_and_push
526 				    (object->package.elements[i], action,
527 				     &state_list);
528 				if (ACPI_FAILURE(status)) {
529 					goto error_exit;
530 				}
531 			}
532 			break;
533 
534 		case ACPI_TYPE_BUFFER_FIELD:
535 
536 			next_object = object->buffer_field.buffer_obj;
537 			break;
538 
539 		case ACPI_TYPE_LOCAL_REGION_FIELD:
540 
541 			next_object = object->field.region_obj;
542 			break;
543 
544 		case ACPI_TYPE_LOCAL_BANK_FIELD:
545 
546 			next_object = object->bank_field.bank_obj;
547 			status =
548 			    acpi_ut_create_update_state_and_push(object->
549 								 bank_field.
550 								 region_obj,
551 								 action,
552 								 &state_list);
553 			if (ACPI_FAILURE(status)) {
554 				goto error_exit;
555 			}
556 			break;
557 
558 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
559 
560 			next_object = object->index_field.index_obj;
561 			status =
562 			    acpi_ut_create_update_state_and_push(object->
563 								 index_field.
564 								 data_obj,
565 								 action,
566 								 &state_list);
567 			if (ACPI_FAILURE(status)) {
568 				goto error_exit;
569 			}
570 			break;
571 
572 		case ACPI_TYPE_LOCAL_REFERENCE:
573 			/*
574 			 * The target of an Index (a package, string, or buffer) or a named
575 			 * reference must track changes to the ref count of the index or
576 			 * target object.
577 			 */
578 			if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
579 			    (object->reference.class == ACPI_REFCLASS_NAME)) {
580 				next_object = object->reference.object;
581 			}
582 			break;
583 
584 		case ACPI_TYPE_REGION:
585 		default:
586 			break;	/* No subobjects for all other types */
587 		}
588 
589 		/*
590 		 * Now we can update the count in the main object. This can only
591 		 * happen after we update the sub-objects in case this causes the
592 		 * main object to be deleted.
593 		 */
594 		acpi_ut_update_ref_count(object, action);
595 		object = NULL;
596 
597 		/* Move on to the next object to be updated */
598 
599 		if (next_object) {
600 			object = next_object;
601 			next_object = NULL;
602 		} else if (state_list) {
603 			state = acpi_ut_pop_generic_state(&state_list);
604 			object = state->update.object;
605 			acpi_ut_delete_generic_state(state);
606 		}
607 	}
608 
609 	return_ACPI_STATUS(AE_OK);
610 
611       error_exit:
612 
613 	ACPI_EXCEPTION((AE_INFO, status,
614 			"Could not update object reference count"));
615 
616 	/* Free any stacked Update State objects */
617 
618 	while (state_list) {
619 		state = acpi_ut_pop_generic_state(&state_list);
620 		acpi_ut_delete_generic_state(state);
621 	}
622 
623 	return_ACPI_STATUS(status);
624 }
625 
626 /*******************************************************************************
627  *
628  * FUNCTION:    acpi_ut_add_reference
629  *
630  * PARAMETERS:  Object          - Object whose reference count is to be
631  *                                incremented
632  *
633  * RETURN:      None
634  *
635  * DESCRIPTION: Add one reference to an ACPI object
636  *
637  ******************************************************************************/
638 
acpi_ut_add_reference(union acpi_operand_object * object)639 void acpi_ut_add_reference(union acpi_operand_object *object)
640 {
641 
642 	ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
643 
644 	/* Ensure that we have a valid object */
645 
646 	if (!acpi_ut_valid_internal_object(object)) {
647 		return_VOID;
648 	}
649 
650 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
651 			  "Obj %p Current Refs=%X [To Be Incremented]\n",
652 			  object, object->common.reference_count));
653 
654 	/* Increment the reference count */
655 
656 	(void)acpi_ut_update_object_reference(object, REF_INCREMENT);
657 	return_VOID;
658 }
659 
660 /*******************************************************************************
661  *
662  * FUNCTION:    acpi_ut_remove_reference
663  *
664  * PARAMETERS:  Object         - Object whose ref count will be decremented
665  *
666  * RETURN:      None
667  *
668  * DESCRIPTION: Decrement the reference count of an ACPI internal object
669  *
670  ******************************************************************************/
671 
acpi_ut_remove_reference(union acpi_operand_object * object)672 void acpi_ut_remove_reference(union acpi_operand_object *object)
673 {
674 
675 	ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
676 
677 	/*
678 	 * Allow a NULL pointer to be passed in, just ignore it. This saves
679 	 * each caller from having to check. Also, ignore NS nodes.
680 	 *
681 	 */
682 	if (!object ||
683 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
684 		return_VOID;
685 	}
686 
687 	/* Ensure that we have a valid object */
688 
689 	if (!acpi_ut_valid_internal_object(object)) {
690 		return_VOID;
691 	}
692 
693 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
694 			  "Obj %p Current Refs=%X [To Be Decremented]\n",
695 			  object, object->common.reference_count));
696 
697 	/*
698 	 * Decrement the reference count, and only actually delete the object
699 	 * if the reference count becomes 0. (Must also decrement the ref count
700 	 * of all subobjects!)
701 	 */
702 	(void)acpi_ut_update_object_reference(object, REF_DECREMENT);
703 	return_VOID;
704 }
705