xref: /linux/drivers/acpi/acpica/utdelete.c (revision 040932cdcfca9b0ac55a4f74f194c2e2c8a2527b)
1 /*******************************************************************************
2  *
3  * Module Name: utdelete - object deletion and reference count utilities
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2008, 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 
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 		second_desc = acpi_ns_get_secondary_object(object);
219 		if (second_desc) {
220 			/*
221 			 * Free the region_context if and only if the handler is one of the
222 			 * default handlers -- and therefore, we created the context object
223 			 * locally, it was not created by an external caller.
224 			 */
225 			handler_desc = object->region.handler;
226 			if (handler_desc) {
227 				next_desc =
228 				    handler_desc->address_space.region_list;
229 				last_obj_ptr =
230 				    &handler_desc->address_space.region_list;
231 
232 				/* Remove the region object from the handler's list */
233 
234 				while (next_desc) {
235 					if (next_desc == object) {
236 						*last_obj_ptr =
237 						    next_desc->region.next;
238 						break;
239 					}
240 
241 					/* Walk the linked list of handler */
242 
243 					last_obj_ptr = &next_desc->region.next;
244 					next_desc = next_desc->region.next;
245 				}
246 
247 				if (handler_desc->address_space.handler_flags &
248 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
249 
250 					/* Deactivate region and free region context */
251 
252 					if (handler_desc->address_space.setup) {
253 						(void)handler_desc->
254 						    address_space.setup(object,
255 									ACPI_REGION_DEACTIVATE,
256 									handler_desc->
257 									address_space.
258 									context,
259 									&second_desc->
260 									extra.
261 									region_context);
262 					}
263 				}
264 
265 				acpi_ut_remove_reference(handler_desc);
266 			}
267 
268 			/* Now we can free the Extra object */
269 
270 			acpi_ut_delete_object_desc(second_desc);
271 		}
272 		break;
273 
274 	case ACPI_TYPE_BUFFER_FIELD:
275 
276 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
277 				  "***** Buffer Field %p\n", object));
278 
279 		second_desc = acpi_ns_get_secondary_object(object);
280 		if (second_desc) {
281 			acpi_ut_delete_object_desc(second_desc);
282 		}
283 		break;
284 
285 	case ACPI_TYPE_LOCAL_BANK_FIELD:
286 
287 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
288 				  "***** Bank Field %p\n", object));
289 
290 		second_desc = acpi_ns_get_secondary_object(object);
291 		if (second_desc) {
292 			acpi_ut_delete_object_desc(second_desc);
293 		}
294 		break;
295 
296 	default:
297 		break;
298 	}
299 
300 	/* Free any allocated memory (pointer within the object) found above */
301 
302 	if (obj_pointer) {
303 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
304 				  "Deleting Object Subptr %p\n", obj_pointer));
305 		ACPI_FREE(obj_pointer);
306 	}
307 
308 	/* Now the object can be safely deleted */
309 
310 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
311 			  object, acpi_ut_get_object_type_name(object)));
312 
313 	acpi_ut_delete_object_desc(object);
314 	return_VOID;
315 }
316 
317 /*******************************************************************************
318  *
319  * FUNCTION:    acpi_ut_delete_internal_object_list
320  *
321  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
322  *
323  * RETURN:      None
324  *
325  * DESCRIPTION: This function deletes an internal object list, including both
326  *              simple objects and package objects
327  *
328  ******************************************************************************/
329 
330 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
331 {
332 	union acpi_operand_object **internal_obj;
333 
334 	ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
335 
336 	/* Walk the null-terminated internal list */
337 
338 	for (internal_obj = obj_list; *internal_obj; internal_obj++) {
339 		acpi_ut_remove_reference(*internal_obj);
340 	}
341 
342 	/* Free the combined parameter pointer list and object array */
343 
344 	ACPI_FREE(obj_list);
345 	return_VOID;
346 }
347 
348 /*******************************************************************************
349  *
350  * FUNCTION:    acpi_ut_update_ref_count
351  *
352  * PARAMETERS:  Object          - Object whose ref count is to be updated
353  *              Action          - What to do
354  *
355  * RETURN:      New ref count
356  *
357  * DESCRIPTION: Modify the ref count and return it.
358  *
359  ******************************************************************************/
360 
361 static void
362 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
363 {
364 	u16 count;
365 	u16 new_count;
366 
367 	ACPI_FUNCTION_NAME(ut_update_ref_count);
368 
369 	if (!object) {
370 		return;
371 	}
372 
373 	count = object->common.reference_count;
374 	new_count = count;
375 
376 	/*
377 	 * Perform the reference count action (increment, decrement, force delete)
378 	 */
379 	switch (action) {
380 	case REF_INCREMENT:
381 
382 		new_count++;
383 		object->common.reference_count = new_count;
384 
385 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
386 				  "Obj %p Refs=%X, [Incremented]\n",
387 				  object, new_count));
388 		break;
389 
390 	case REF_DECREMENT:
391 
392 		if (count < 1) {
393 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
394 					  "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
395 					  object, new_count));
396 
397 			new_count = 0;
398 		} else {
399 			new_count--;
400 
401 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
402 					  "Obj %p Refs=%X, [Decremented]\n",
403 					  object, new_count));
404 		}
405 
406 		if (object->common.type == ACPI_TYPE_METHOD) {
407 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
408 					  "Method Obj %p Refs=%X, [Decremented]\n",
409 					  object, new_count));
410 		}
411 
412 		object->common.reference_count = new_count;
413 		if (new_count == 0) {
414 			acpi_ut_delete_internal_obj(object);
415 		}
416 		break;
417 
418 	case REF_FORCE_DELETE:
419 
420 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
421 				  "Obj %p Refs=%X, Force delete! (Set to 0)\n",
422 				  object, count));
423 
424 		new_count = 0;
425 		object->common.reference_count = new_count;
426 		acpi_ut_delete_internal_obj(object);
427 		break;
428 
429 	default:
430 
431 		ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
432 		break;
433 	}
434 
435 	/*
436 	 * Sanity check the reference count, for debug purposes only.
437 	 * (A deleted object will have a huge reference count)
438 	 */
439 	if (count > ACPI_MAX_REFERENCE_COUNT) {
440 		ACPI_WARNING((AE_INFO,
441 			      "Large Reference Count (%X) in object %p", count,
442 			      object));
443 	}
444 }
445 
446 /*******************************************************************************
447  *
448  * FUNCTION:    acpi_ut_update_object_reference
449  *
450  * PARAMETERS:  Object              - Increment ref count for this object
451  *                                    and all sub-objects
452  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
453  *                                    REF_FORCE_DELETE
454  *
455  * RETURN:      Status
456  *
457  * DESCRIPTION: Increment the object reference count
458  *
459  * Object references are incremented when:
460  * 1) An object is attached to a Node (namespace object)
461  * 2) An object is copied (all subobjects must be incremented)
462  *
463  * Object references are decremented when:
464  * 1) An object is detached from an Node
465  *
466  ******************************************************************************/
467 
468 acpi_status
469 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
470 {
471 	acpi_status status = AE_OK;
472 	union acpi_generic_state *state_list = NULL;
473 	union acpi_operand_object *next_object = NULL;
474 	union acpi_generic_state *state;
475 	u32 i;
476 
477 	ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
478 
479 	while (object) {
480 
481 		/* Make sure that this isn't a namespace handle */
482 
483 		if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
484 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
485 					  "Object %p is NS handle\n", object));
486 			return_ACPI_STATUS(AE_OK);
487 		}
488 
489 		/*
490 		 * All sub-objects must have their reference count incremented also.
491 		 * Different object types have different subobjects.
492 		 */
493 		switch (object->common.type) {
494 		case ACPI_TYPE_DEVICE:
495 		case ACPI_TYPE_PROCESSOR:
496 		case ACPI_TYPE_POWER:
497 		case ACPI_TYPE_THERMAL:
498 
499 			/* Update the notify objects for these types (if present) */
500 
501 			acpi_ut_update_ref_count(object->common_notify.
502 						 system_notify, action);
503 			acpi_ut_update_ref_count(object->common_notify.
504 						 device_notify, action);
505 			break;
506 
507 		case ACPI_TYPE_PACKAGE:
508 			/*
509 			 * We must update all the sub-objects of the package,
510 			 * each of whom may have their own sub-objects.
511 			 */
512 			for (i = 0; i < object->package.count; i++) {
513 				/*
514 				 * Push each element onto the stack for later processing.
515 				 * Note: There can be null elements within the package,
516 				 * these are simply ignored
517 				 */
518 				status =
519 				    acpi_ut_create_update_state_and_push
520 				    (object->package.elements[i], action,
521 				     &state_list);
522 				if (ACPI_FAILURE(status)) {
523 					goto error_exit;
524 				}
525 			}
526 			break;
527 
528 		case ACPI_TYPE_BUFFER_FIELD:
529 
530 			next_object = object->buffer_field.buffer_obj;
531 			break;
532 
533 		case ACPI_TYPE_LOCAL_REGION_FIELD:
534 
535 			next_object = object->field.region_obj;
536 			break;
537 
538 		case ACPI_TYPE_LOCAL_BANK_FIELD:
539 
540 			next_object = object->bank_field.bank_obj;
541 			status =
542 			    acpi_ut_create_update_state_and_push(object->
543 								 bank_field.
544 								 region_obj,
545 								 action,
546 								 &state_list);
547 			if (ACPI_FAILURE(status)) {
548 				goto error_exit;
549 			}
550 			break;
551 
552 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
553 
554 			next_object = object->index_field.index_obj;
555 			status =
556 			    acpi_ut_create_update_state_and_push(object->
557 								 index_field.
558 								 data_obj,
559 								 action,
560 								 &state_list);
561 			if (ACPI_FAILURE(status)) {
562 				goto error_exit;
563 			}
564 			break;
565 
566 		case ACPI_TYPE_LOCAL_REFERENCE:
567 			/*
568 			 * The target of an Index (a package, string, or buffer) or a named
569 			 * reference must track changes to the ref count of the index or
570 			 * target object.
571 			 */
572 			if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
573 			    (object->reference.class == ACPI_REFCLASS_NAME)) {
574 				next_object = object->reference.object;
575 			}
576 			break;
577 
578 		case ACPI_TYPE_REGION:
579 		default:
580 			break;	/* No subobjects for all other types */
581 		}
582 
583 		/*
584 		 * Now we can update the count in the main object. This can only
585 		 * happen after we update the sub-objects in case this causes the
586 		 * main object to be deleted.
587 		 */
588 		acpi_ut_update_ref_count(object, action);
589 		object = NULL;
590 
591 		/* Move on to the next object to be updated */
592 
593 		if (next_object) {
594 			object = next_object;
595 			next_object = NULL;
596 		} else if (state_list) {
597 			state = acpi_ut_pop_generic_state(&state_list);
598 			object = state->update.object;
599 			acpi_ut_delete_generic_state(state);
600 		}
601 	}
602 
603 	return_ACPI_STATUS(AE_OK);
604 
605       error_exit:
606 
607 	ACPI_EXCEPTION((AE_INFO, status,
608 			"Could not update object reference count"));
609 
610 	/* Free any stacked Update State objects */
611 
612 	while (state_list) {
613 		state = acpi_ut_pop_generic_state(&state_list);
614 		acpi_ut_delete_generic_state(state);
615 	}
616 
617 	return_ACPI_STATUS(status);
618 }
619 
620 /*******************************************************************************
621  *
622  * FUNCTION:    acpi_ut_add_reference
623  *
624  * PARAMETERS:  Object          - Object whose reference count is to be
625  *                                incremented
626  *
627  * RETURN:      None
628  *
629  * DESCRIPTION: Add one reference to an ACPI object
630  *
631  ******************************************************************************/
632 
633 void acpi_ut_add_reference(union acpi_operand_object *object)
634 {
635 
636 	ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
637 
638 	/* Ensure that we have a valid object */
639 
640 	if (!acpi_ut_valid_internal_object(object)) {
641 		return_VOID;
642 	}
643 
644 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
645 			  "Obj %p Current Refs=%X [To Be Incremented]\n",
646 			  object, object->common.reference_count));
647 
648 	/* Increment the reference count */
649 
650 	(void)acpi_ut_update_object_reference(object, REF_INCREMENT);
651 	return_VOID;
652 }
653 
654 /*******************************************************************************
655  *
656  * FUNCTION:    acpi_ut_remove_reference
657  *
658  * PARAMETERS:  Object         - Object whose ref count will be decremented
659  *
660  * RETURN:      None
661  *
662  * DESCRIPTION: Decrement the reference count of an ACPI internal object
663  *
664  ******************************************************************************/
665 
666 void acpi_ut_remove_reference(union acpi_operand_object *object)
667 {
668 
669 	ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
670 
671 	/*
672 	 * Allow a NULL pointer to be passed in, just ignore it. This saves
673 	 * each caller from having to check. Also, ignore NS nodes.
674 	 *
675 	 */
676 	if (!object ||
677 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
678 		return_VOID;
679 	}
680 
681 	/* Ensure that we have a valid object */
682 
683 	if (!acpi_ut_valid_internal_object(object)) {
684 		return_VOID;
685 	}
686 
687 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
688 			  "Obj %p Current Refs=%X [To Be Decremented]\n",
689 			  object, object->common.reference_count));
690 
691 	/*
692 	 * Decrement the reference count, and only actually delete the object
693 	 * if the reference count becomes 0. (Must also decrement the ref count
694 	 * of all subobjects!)
695 	 */
696 	(void)acpi_ut_update_object_reference(object, REF_DECREMENT);
697 	return_VOID;
698 }
699