1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /*******************************************************************************
3 *
4 * Module Name: utdelete - object deletion and reference count utilities
5 *
6 ******************************************************************************/
7
8 #include <acpi/acpi.h>
9 #include "accommon.h"
10 #include "acinterp.h"
11 #include "acnamesp.h"
12 #include "acevents.h"
13
14 #define _COMPONENT ACPI_UTILITIES
15 ACPI_MODULE_NAME("utdelete")
16
17 /* Local prototypes */
18 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object);
19
20 static void
21 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action);
22
23 /*******************************************************************************
24 *
25 * FUNCTION: acpi_ut_delete_internal_obj
26 *
27 * PARAMETERS: object - Object to be deleted
28 *
29 * RETURN: None
30 *
31 * DESCRIPTION: Low level object deletion, after reference counts have been
32 * updated (All reference counts, including sub-objects!)
33 *
34 ******************************************************************************/
35
36 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
37 {
38 void *obj_pointer = NULL;
39 union acpi_operand_object *handler_desc;
40 union acpi_operand_object *second_desc;
41 union acpi_operand_object *next_desc;
42 union acpi_operand_object *start_desc;
43 union acpi_operand_object **last_obj_ptr;
44
45 ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
46
47 if (!object) {
48 return_VOID;
49 }
50
51 /*
52 * Must delete or free any pointers within the object that are not
53 * actual ACPI objects (for example, a raw buffer pointer).
54 */
55 switch (object->common.type) {
56 case ACPI_TYPE_STRING:
57
58 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
59 "**** String %p, ptr %p\n", object,
60 object->string.pointer));
61
62 /* Free the actual string buffer */
63
64 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
65
66 /* But only if it is NOT a pointer into an ACPI table */
67
68 obj_pointer = object->string.pointer;
69 }
70 break;
71
72 case ACPI_TYPE_BUFFER:
73
74 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
75 "**** Buffer %p, ptr %p\n", object,
76 object->buffer.pointer));
77
78 /* Free the actual buffer */
79
80 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
81
82 /* But only if it is NOT a pointer into an ACPI table */
83
84 obj_pointer = object->buffer.pointer;
85 }
86 break;
87
88 case ACPI_TYPE_PACKAGE:
89
90 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
91 " **** Package of count %X\n",
92 object->package.count));
93
94 /*
95 * Elements of the package are not handled here, they are deleted
96 * separately
97 */
98
99 /* Free the (variable length) element pointer array */
100
101 obj_pointer = object->package.elements;
102 break;
103
104 /*
105 * These objects have a possible list of notify handlers.
106 * Device object also may have a GPE block.
107 */
108 case ACPI_TYPE_DEVICE:
109
110 if (object->device.gpe_block) {
111 (void)acpi_ev_delete_gpe_block(object->device.
112 gpe_block);
113 }
114
115 /*lint -fallthrough */
116
117 case ACPI_TYPE_PROCESSOR:
118 case ACPI_TYPE_THERMAL:
119
120 /* Walk the address handler list for this object */
121
122 handler_desc = object->common_notify.handler;
123 while (handler_desc) {
124 next_desc = handler_desc->address_space.next;
125 acpi_ut_remove_reference(handler_desc);
126 handler_desc = next_desc;
127 }
128 break;
129
130 case ACPI_TYPE_MUTEX:
131
132 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
133 "***** Mutex %p, OS Mutex %p\n",
134 object, object->mutex.os_mutex));
135
136 if (object == acpi_gbl_global_lock_mutex) {
137
138 /* Global Lock has extra semaphore */
139
140 (void)
141 acpi_os_delete_semaphore
142 (acpi_gbl_global_lock_semaphore);
143 acpi_gbl_global_lock_semaphore = NULL;
144
145 acpi_os_delete_mutex(object->mutex.os_mutex);
146 acpi_gbl_global_lock_mutex = NULL;
147 } else {
148 acpi_ex_unlink_mutex(object);
149 acpi_os_delete_mutex(object->mutex.os_mutex);
150 }
151 break;
152
153 case ACPI_TYPE_EVENT:
154
155 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
156 "***** Event %p, OS Semaphore %p\n",
157 object, object->event.os_semaphore));
158
159 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
160 object->event.os_semaphore = NULL;
161 break;
162
163 case ACPI_TYPE_METHOD:
164
165 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
166 "***** Method %p\n", object));
167
168 /* Delete the method mutex if it exists */
169
170 if (object->method.mutex) {
171 acpi_os_delete_mutex(object->method.mutex->mutex.
172 os_mutex);
173 acpi_ut_delete_object_desc(object->method.mutex);
174 object->method.mutex = NULL;
175 }
176
177 if (object->method.node) {
178 object->method.node = NULL;
179 }
180 break;
181
182 case ACPI_TYPE_REGION:
183
184 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
185 "***** Region %p\n", object));
186
187 /*
188 * Update address_range list. However, only permanent regions
189 * are installed in this list. (Not created within a method)
190 */
191 if (!(object->region.node->flags & ANOBJ_TEMPORARY)) {
192 acpi_ut_remove_address_range(object->region.space_id,
193 object->region.node);
194 }
195
196 second_desc = acpi_ns_get_secondary_object(object);
197 if (second_desc) {
198 /*
199 * Free the region_context if and only if the handler is one of the
200 * default handlers -- and therefore, we created the context object
201 * locally, it was not created by an external caller.
202 */
203 handler_desc = object->region.handler;
204 if (handler_desc) {
205 next_desc =
206 handler_desc->address_space.region_list;
207 start_desc = next_desc;
208 last_obj_ptr =
209 &handler_desc->address_space.region_list;
210
211 /* Remove the region object from the handler list */
212
213 while (next_desc) {
214 if (next_desc == object) {
215 *last_obj_ptr =
216 next_desc->region.next;
217 break;
218 }
219
220 /* Walk the linked list of handlers */
221
222 last_obj_ptr = &next_desc->region.next;
223 next_desc = next_desc->region.next;
224
225 /* Prevent infinite loop if list is corrupted */
226
227 if (next_desc == start_desc) {
228 ACPI_ERROR((AE_INFO,
229 "Circular region list in address handler object %p",
230 handler_desc));
231 return_VOID;
232 }
233 }
234
235 if (handler_desc->address_space.handler_flags &
236 ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
237
238 /* Deactivate region and free region context */
239
240 if (handler_desc->address_space.setup) {
241 (void)handler_desc->
242 address_space.setup(object,
243 ACPI_REGION_DEACTIVATE,
244 handler_desc->
245 address_space.
246 context,
247 &second_desc->
248 extra.
249 region_context);
250 }
251 }
252
253 acpi_ut_remove_reference(handler_desc);
254 }
255
256 /* Now we can free the Extra object */
257
258 acpi_ut_delete_object_desc(second_desc);
259 }
260 if (object->field.internal_pcc_buffer) {
261 ACPI_FREE(object->field.internal_pcc_buffer);
262 }
263
264 break;
265
266 case ACPI_TYPE_BUFFER_FIELD:
267
268 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
269 "***** Buffer Field %p\n", object));
270
271 second_desc = acpi_ns_get_secondary_object(object);
272 if (second_desc) {
273 acpi_ut_delete_object_desc(second_desc);
274 }
275 break;
276
277 case ACPI_TYPE_LOCAL_BANK_FIELD:
278
279 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
280 "***** Bank Field %p\n", object));
281
282 second_desc = acpi_ns_get_secondary_object(object);
283 if (second_desc) {
284 acpi_ut_delete_object_desc(second_desc);
285 }
286 break;
287
288 default:
289
290 break;
291 }
292
293 /* Free any allocated memory (pointer within the object) found above */
294
295 if (obj_pointer) {
296 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
297 "Deleting Object Subptr %p\n", obj_pointer));
298 ACPI_FREE(obj_pointer);
299 }
300
301 /* Now the object can be safely deleted */
302
303 ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
304 "%s: Deleting Object %p [%s]\n",
305 ACPI_GET_FUNCTION_NAME, object,
306 acpi_ut_get_object_type_name(object)));
307
308 acpi_ut_delete_object_desc(object);
309 return_VOID;
310 }
311
312 /*******************************************************************************
313 *
314 * FUNCTION: acpi_ut_delete_internal_object_list
315 *
316 * PARAMETERS: obj_list - Pointer to the list to be deleted
317 *
318 * RETURN: None
319 *
320 * DESCRIPTION: This function deletes an internal object list, including both
321 * simple objects and package objects
322 *
323 ******************************************************************************/
324
325 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
326 {
327 union acpi_operand_object **internal_obj;
328
329 ACPI_FUNCTION_ENTRY();
330
331 /* Walk the null-terminated internal list */
332
333 for (internal_obj = obj_list; *internal_obj; internal_obj++) {
334 acpi_ut_remove_reference(*internal_obj);
335 }
336
337 /* Free the combined parameter pointer list and object array */
338
339 ACPI_FREE(obj_list);
340 return;
341 }
342
343 /*******************************************************************************
344 *
345 * FUNCTION: acpi_ut_update_ref_count
346 *
347 * PARAMETERS: object - Object whose ref count is to be updated
348 * action - What to do (REF_INCREMENT or REF_DECREMENT)
349 *
350 * RETURN: None. Sets new reference count within the object
351 *
352 * DESCRIPTION: Modify the reference count for an internal acpi object
353 *
354 ******************************************************************************/
355
356 static void
357 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
358 {
359 u16 original_count;
360 u16 new_count = 0;
361 acpi_cpu_flags lock_flags;
362 char *message;
363
364 ACPI_FUNCTION_NAME(ut_update_ref_count);
365
366 if (!object) {
367 return;
368 }
369
370 /*
371 * Always get the reference count lock. Note: Interpreter and/or
372 * Namespace is not always locked when this function is called.
373 */
374 lock_flags = acpi_os_acquire_lock(acpi_gbl_reference_count_lock);
375 original_count = object->common.reference_count;
376
377 /* Perform the reference count action (increment, decrement) */
378
379 switch (action) {
380 case REF_INCREMENT:
381
382 new_count = original_count + 1;
383 object->common.reference_count = new_count;
384 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
385
386 /* The current reference count should never be zero here */
387
388 if (!original_count) {
389 ACPI_WARNING((AE_INFO,
390 "Obj %p, Reference Count was zero before increment\n",
391 object));
392 }
393
394 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
395 "Obj %p Type %.2X [%s] Refs %.2X [Incremented]\n",
396 object, object->common.type,
397 acpi_ut_get_object_type_name(object),
398 new_count));
399 message = "Incremement";
400 break;
401
402 case REF_DECREMENT:
403
404 /* The current reference count must be non-zero */
405
406 if (original_count) {
407 new_count = original_count - 1;
408 object->common.reference_count = new_count;
409 }
410
411 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
412
413 if (!original_count) {
414 ACPI_WARNING((AE_INFO,
415 "Obj %p, Reference Count is already zero, cannot decrement\n",
416 object));
417 }
418
419 ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
420 "%s: Obj %p Type %.2X Refs %.2X [Decremented]\n",
421 ACPI_GET_FUNCTION_NAME, object,
422 object->common.type, new_count));
423
424 /* Actually delete the object on a reference count of zero */
425
426 if (new_count == 0) {
427 acpi_ut_delete_internal_obj(object);
428 }
429 message = "Decrement";
430 break;
431
432 default:
433
434 acpi_os_release_lock(acpi_gbl_reference_count_lock, lock_flags);
435 ACPI_ERROR((AE_INFO, "Unknown Reference Count action (0x%X)",
436 action));
437 return;
438 }
439
440 /*
441 * Sanity check the reference count, for debug purposes only.
442 * (A deleted object will have a huge reference count)
443 */
444 if (new_count > ACPI_MAX_REFERENCE_COUNT) {
445 ACPI_WARNING((AE_INFO,
446 "Large Reference Count (0x%X) in object %p, Type=0x%.2X Operation=%s",
447 new_count, object, object->common.type, message));
448 }
449 }
450
451 /*******************************************************************************
452 *
453 * FUNCTION: acpi_ut_update_object_reference
454 *
455 * PARAMETERS: object - Increment or decrement the ref count for
456 * this object and all sub-objects
457 * action - Either REF_INCREMENT or REF_DECREMENT
458 *
459 * RETURN: Status
460 *
461 * DESCRIPTION: Increment or decrement the object reference count
462 *
463 * Object references are incremented when:
464 * 1) An object is attached to a Node (namespace object)
465 * 2) An object is copied (all subobjects must be incremented)
466 *
467 * Object references are decremented when:
468 * 1) An object is detached from an Node
469 *
470 ******************************************************************************/
471
472 acpi_status
473 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
474 {
475 acpi_status status = AE_OK;
476 union acpi_generic_state *state_list = NULL;
477 union acpi_operand_object *next_object = NULL;
478 union acpi_operand_object *prev_object;
479 union acpi_generic_state *state;
480 u32 i;
481
482 ACPI_FUNCTION_NAME(ut_update_object_reference);
483
484 while (object) {
485
486 /* Make sure that this isn't a namespace handle */
487
488 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
489 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
490 "Object %p is NS handle\n", object));
491 return (AE_OK);
492 }
493
494 /*
495 * All sub-objects must have their reference count updated
496 * also. Different object types have different subobjects.
497 */
498 switch (object->common.type) {
499 case ACPI_TYPE_DEVICE:
500 case ACPI_TYPE_PROCESSOR:
501 case ACPI_TYPE_POWER:
502 case ACPI_TYPE_THERMAL:
503 /*
504 * Update the notify objects for these types (if present)
505 * Two lists, system and device notify handlers.
506 */
507 for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
508 prev_object =
509 object->common_notify.notify_list[i];
510 while (prev_object) {
511 next_object =
512 prev_object->notify.next[i];
513 acpi_ut_update_ref_count(prev_object,
514 action);
515 prev_object = next_object;
516 }
517 }
518 break;
519
520 case ACPI_TYPE_PACKAGE:
521 /*
522 * We must update all the sub-objects of the package,
523 * each of whom may have their own sub-objects.
524 */
525 for (i = 0; i < object->package.count; i++) {
526 /*
527 * Null package elements are legal and can be simply
528 * ignored.
529 */
530 next_object = object->package.elements[i];
531 if (!next_object) {
532 continue;
533 }
534
535 switch (next_object->common.type) {
536 case ACPI_TYPE_INTEGER:
537 case ACPI_TYPE_STRING:
538 case ACPI_TYPE_BUFFER:
539 /*
540 * For these very simple sub-objects, we can just
541 * update the reference count here and continue.
542 * Greatly increases performance of this operation.
543 */
544 acpi_ut_update_ref_count(next_object,
545 action);
546 break;
547
548 default:
549 /*
550 * For complex sub-objects, push them onto the stack
551 * for later processing (this eliminates recursion.)
552 */
553 status =
554 acpi_ut_create_update_state_and_push
555 (next_object, action, &state_list);
556 if (ACPI_FAILURE(status)) {
557 goto error_exit;
558 }
559 break;
560 }
561 }
562
563 next_object = NULL;
564 break;
565
566 case ACPI_TYPE_BUFFER_FIELD:
567
568 next_object = object->buffer_field.buffer_obj;
569 break;
570
571 case ACPI_TYPE_LOCAL_REGION_FIELD:
572
573 next_object = object->field.region_obj;
574 break;
575
576 case ACPI_TYPE_LOCAL_BANK_FIELD:
577
578 next_object = object->bank_field.bank_obj;
579 status =
580 acpi_ut_create_update_state_and_push(object->
581 bank_field.
582 region_obj,
583 action,
584 &state_list);
585 if (ACPI_FAILURE(status)) {
586 goto error_exit;
587 }
588 break;
589
590 case ACPI_TYPE_LOCAL_INDEX_FIELD:
591
592 next_object = object->index_field.index_obj;
593 status =
594 acpi_ut_create_update_state_and_push(object->
595 index_field.
596 data_obj,
597 action,
598 &state_list);
599 if (ACPI_FAILURE(status)) {
600 goto error_exit;
601 }
602 break;
603
604 case ACPI_TYPE_LOCAL_REFERENCE:
605 /*
606 * The target of an Index (a package, string, or buffer) or a named
607 * reference must track changes to the ref count of the index or
608 * target object.
609 */
610 if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
611 (object->reference.class == ACPI_REFCLASS_NAME)) {
612 next_object = object->reference.object;
613 }
614 break;
615
616 case ACPI_TYPE_REGION:
617 default:
618
619 break; /* No subobjects for all other types */
620 }
621
622 /*
623 * Now we can update the count in the main object. This can only
624 * happen after we update the sub-objects in case this causes the
625 * main object to be deleted.
626 */
627 acpi_ut_update_ref_count(object, action);
628 object = NULL;
629
630 /* Move on to the next object to be updated */
631
632 if (next_object) {
633 object = next_object;
634 next_object = NULL;
635 } else if (state_list) {
636 state = acpi_ut_pop_generic_state(&state_list);
637 object = state->update.object;
638 acpi_ut_delete_generic_state(state);
639 }
640 }
641
642 return (AE_OK);
643
644 error_exit:
645
646 ACPI_EXCEPTION((AE_INFO, status,
647 "Could not update object reference count"));
648
649 /* Free any stacked Update State objects */
650
651 while (state_list) {
652 state = acpi_ut_pop_generic_state(&state_list);
653 acpi_ut_delete_generic_state(state);
654 }
655
656 return (status);
657 }
658
659 /*******************************************************************************
660 *
661 * FUNCTION: acpi_ut_add_reference
662 *
663 * PARAMETERS: object - Object whose reference count is to be
664 * incremented
665 *
666 * RETURN: None
667 *
668 * DESCRIPTION: Add one reference to an ACPI object
669 *
670 ******************************************************************************/
671
672 void acpi_ut_add_reference(union acpi_operand_object *object)
673 {
674
675 ACPI_FUNCTION_NAME(ut_add_reference);
676
677 /* Ensure that we have a valid object */
678
679 if (!acpi_ut_valid_internal_object(object)) {
680 return;
681 }
682
683 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
684 "Obj %p Current Refs=%X [To Be Incremented]\n",
685 object, object->common.reference_count));
686
687 /* Increment the reference count */
688
689 (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
690 return;
691 }
692
693 /*******************************************************************************
694 *
695 * FUNCTION: acpi_ut_remove_reference
696 *
697 * PARAMETERS: object - Object whose ref count will be decremented
698 *
699 * RETURN: None
700 *
701 * DESCRIPTION: Decrement the reference count of an ACPI internal object
702 *
703 ******************************************************************************/
704
705 void acpi_ut_remove_reference(union acpi_operand_object *object)
706 {
707
708 ACPI_FUNCTION_NAME(ut_remove_reference);
709
710 /*
711 * Allow a NULL pointer to be passed in, just ignore it. This saves
712 * each caller from having to check. Also, ignore NS nodes.
713 */
714 if (!object ||
715 (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
716 return;
717 }
718
719 /* Ensure that we have a valid object */
720
721 if (!acpi_ut_valid_internal_object(object)) {
722 return;
723 }
724
725 ACPI_DEBUG_PRINT_RAW((ACPI_DB_ALLOCATIONS,
726 "%s: Obj %p Current Refs=%X [To Be Decremented]\n",
727 ACPI_GET_FUNCTION_NAME, object,
728 object->common.reference_count));
729
730 /*
731 * Decrement the reference count, and only actually delete the object
732 * if the reference count becomes 0. (Must also decrement the ref count
733 * of all subobjects!)
734 */
735 (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
736 return;
737 }