xref: /openbmc/linux/drivers/acpi/acpica/utdelete.c (revision b04b4f78)
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 
79 	ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
80 
81 	if (!object) {
82 		return_VOID;
83 	}
84 
85 	/*
86 	 * Must delete or free any pointers within the object that are not
87 	 * actual ACPI objects (for example, a raw buffer pointer).
88 	 */
89 	switch (object->common.type) {
90 	case ACPI_TYPE_STRING:
91 
92 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
93 				  "**** String %p, ptr %p\n", object,
94 				  object->string.pointer));
95 
96 		/* Free the actual string buffer */
97 
98 		if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
99 
100 			/* But only if it is NOT a pointer into an ACPI table */
101 
102 			obj_pointer = object->string.pointer;
103 		}
104 		break;
105 
106 	case ACPI_TYPE_BUFFER:
107 
108 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
109 				  "**** Buffer %p, ptr %p\n", object,
110 				  object->buffer.pointer));
111 
112 		/* Free the actual buffer */
113 
114 		if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
115 
116 			/* But only if it is NOT a pointer into an ACPI table */
117 
118 			obj_pointer = object->buffer.pointer;
119 		}
120 		break;
121 
122 	case ACPI_TYPE_PACKAGE:
123 
124 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
125 				  " **** Package of count %X\n",
126 				  object->package.count));
127 
128 		/*
129 		 * Elements of the package are not handled here, they are deleted
130 		 * separately
131 		 */
132 
133 		/* Free the (variable length) element pointer array */
134 
135 		obj_pointer = object->package.elements;
136 		break;
137 
138 		/*
139 		 * These objects have a possible list of notify handlers.
140 		 * Device object also may have a GPE block.
141 		 */
142 	case ACPI_TYPE_DEVICE:
143 
144 		if (object->device.gpe_block) {
145 			(void)acpi_ev_delete_gpe_block(object->device.
146 						       gpe_block);
147 		}
148 
149 		/*lint -fallthrough */
150 
151 	case ACPI_TYPE_PROCESSOR:
152 	case ACPI_TYPE_THERMAL:
153 
154 		/* Walk the notify handler list for this object */
155 
156 		handler_desc = object->common_notify.handler;
157 		while (handler_desc) {
158 			next_desc = handler_desc->address_space.next;
159 			acpi_ut_remove_reference(handler_desc);
160 			handler_desc = next_desc;
161 		}
162 		break;
163 
164 	case ACPI_TYPE_MUTEX:
165 
166 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
167 				  "***** Mutex %p, OS Mutex %p\n",
168 				  object, object->mutex.os_mutex));
169 
170 		if (object == acpi_gbl_global_lock_mutex) {
171 
172 			/* Global Lock has extra semaphore */
173 
174 			(void)
175 			    acpi_os_delete_semaphore
176 			    (acpi_gbl_global_lock_semaphore);
177 			acpi_gbl_global_lock_semaphore = NULL;
178 
179 			acpi_os_delete_mutex(object->mutex.os_mutex);
180 			acpi_gbl_global_lock_mutex = NULL;
181 		} else {
182 			acpi_ex_unlink_mutex(object);
183 			acpi_os_delete_mutex(object->mutex.os_mutex);
184 		}
185 		break;
186 
187 	case ACPI_TYPE_EVENT:
188 
189 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
190 				  "***** Event %p, OS Semaphore %p\n",
191 				  object, object->event.os_semaphore));
192 
193 		(void)acpi_os_delete_semaphore(object->event.os_semaphore);
194 		object->event.os_semaphore = NULL;
195 		break;
196 
197 	case ACPI_TYPE_METHOD:
198 
199 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
200 				  "***** Method %p\n", object));
201 
202 		/* Delete the method mutex if it exists */
203 
204 		if (object->method.mutex) {
205 			acpi_os_delete_mutex(object->method.mutex->mutex.
206 					     os_mutex);
207 			acpi_ut_delete_object_desc(object->method.mutex);
208 			object->method.mutex = NULL;
209 		}
210 		break;
211 
212 	case ACPI_TYPE_REGION:
213 
214 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
215 				  "***** Region %p\n", object));
216 
217 		second_desc = acpi_ns_get_secondary_object(object);
218 		if (second_desc) {
219 			/*
220 			 * Free the region_context if and only if the handler is one of the
221 			 * default handlers -- and therefore, we created the context object
222 			 * locally, it was not created by an external caller.
223 			 */
224 			handler_desc = object->region.handler;
225 			if (handler_desc) {
226 				if (handler_desc->address_space.handler_flags &
227 				    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
228 
229 					/* Deactivate region and free region context */
230 
231 					if (handler_desc->address_space.setup) {
232 						(void)handler_desc->
233 						    address_space.setup(object,
234 									ACPI_REGION_DEACTIVATE,
235 									handler_desc->
236 									address_space.
237 									context,
238 									&second_desc->
239 									extra.
240 									region_context);
241 					}
242 				}
243 
244 				acpi_ut_remove_reference(handler_desc);
245 			}
246 
247 			/* Now we can free the Extra object */
248 
249 			acpi_ut_delete_object_desc(second_desc);
250 		}
251 		break;
252 
253 	case ACPI_TYPE_BUFFER_FIELD:
254 
255 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
256 				  "***** Buffer Field %p\n", object));
257 
258 		second_desc = acpi_ns_get_secondary_object(object);
259 		if (second_desc) {
260 			acpi_ut_delete_object_desc(second_desc);
261 		}
262 		break;
263 
264 	case ACPI_TYPE_LOCAL_BANK_FIELD:
265 
266 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
267 				  "***** Bank Field %p\n", object));
268 
269 		second_desc = acpi_ns_get_secondary_object(object);
270 		if (second_desc) {
271 			acpi_ut_delete_object_desc(second_desc);
272 		}
273 		break;
274 
275 	default:
276 		break;
277 	}
278 
279 	/* Free any allocated memory (pointer within the object) found above */
280 
281 	if (obj_pointer) {
282 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
283 				  "Deleting Object Subptr %p\n", obj_pointer));
284 		ACPI_FREE(obj_pointer);
285 	}
286 
287 	/* Now the object can be safely deleted */
288 
289 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
290 			  object, acpi_ut_get_object_type_name(object)));
291 
292 	acpi_ut_delete_object_desc(object);
293 	return_VOID;
294 }
295 
296 /*******************************************************************************
297  *
298  * FUNCTION:    acpi_ut_delete_internal_object_list
299  *
300  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
301  *
302  * RETURN:      None
303  *
304  * DESCRIPTION: This function deletes an internal object list, including both
305  *              simple objects and package objects
306  *
307  ******************************************************************************/
308 
309 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
310 {
311 	union acpi_operand_object **internal_obj;
312 
313 	ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
314 
315 	/* Walk the null-terminated internal list */
316 
317 	for (internal_obj = obj_list; *internal_obj; internal_obj++) {
318 		acpi_ut_remove_reference(*internal_obj);
319 	}
320 
321 	/* Free the combined parameter pointer list and object array */
322 
323 	ACPI_FREE(obj_list);
324 	return_VOID;
325 }
326 
327 /*******************************************************************************
328  *
329  * FUNCTION:    acpi_ut_update_ref_count
330  *
331  * PARAMETERS:  Object          - Object whose ref count is to be updated
332  *              Action          - What to do
333  *
334  * RETURN:      New ref count
335  *
336  * DESCRIPTION: Modify the ref count and return it.
337  *
338  ******************************************************************************/
339 
340 static void
341 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
342 {
343 	u16 count;
344 	u16 new_count;
345 
346 	ACPI_FUNCTION_NAME(ut_update_ref_count);
347 
348 	if (!object) {
349 		return;
350 	}
351 
352 	count = object->common.reference_count;
353 	new_count = count;
354 
355 	/*
356 	 * Perform the reference count action (increment, decrement, force delete)
357 	 */
358 	switch (action) {
359 	case REF_INCREMENT:
360 
361 		new_count++;
362 		object->common.reference_count = new_count;
363 
364 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
365 				  "Obj %p Refs=%X, [Incremented]\n",
366 				  object, new_count));
367 		break;
368 
369 	case REF_DECREMENT:
370 
371 		if (count < 1) {
372 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
373 					  "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
374 					  object, new_count));
375 
376 			new_count = 0;
377 		} else {
378 			new_count--;
379 
380 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
381 					  "Obj %p Refs=%X, [Decremented]\n",
382 					  object, new_count));
383 		}
384 
385 		if (object->common.type == ACPI_TYPE_METHOD) {
386 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
387 					  "Method Obj %p Refs=%X, [Decremented]\n",
388 					  object, new_count));
389 		}
390 
391 		object->common.reference_count = new_count;
392 		if (new_count == 0) {
393 			acpi_ut_delete_internal_obj(object);
394 		}
395 		break;
396 
397 	case REF_FORCE_DELETE:
398 
399 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
400 				  "Obj %p Refs=%X, Force delete! (Set to 0)\n",
401 				  object, count));
402 
403 		new_count = 0;
404 		object->common.reference_count = new_count;
405 		acpi_ut_delete_internal_obj(object);
406 		break;
407 
408 	default:
409 
410 		ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
411 		break;
412 	}
413 
414 	/*
415 	 * Sanity check the reference count, for debug purposes only.
416 	 * (A deleted object will have a huge reference count)
417 	 */
418 	if (count > ACPI_MAX_REFERENCE_COUNT) {
419 		ACPI_WARNING((AE_INFO,
420 			      "Large Reference Count (%X) in object %p", count,
421 			      object));
422 	}
423 }
424 
425 /*******************************************************************************
426  *
427  * FUNCTION:    acpi_ut_update_object_reference
428  *
429  * PARAMETERS:  Object              - Increment ref count for this object
430  *                                    and all sub-objects
431  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
432  *                                    REF_FORCE_DELETE
433  *
434  * RETURN:      Status
435  *
436  * DESCRIPTION: Increment the object reference count
437  *
438  * Object references are incremented when:
439  * 1) An object is attached to a Node (namespace object)
440  * 2) An object is copied (all subobjects must be incremented)
441  *
442  * Object references are decremented when:
443  * 1) An object is detached from an Node
444  *
445  ******************************************************************************/
446 
447 acpi_status
448 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
449 {
450 	acpi_status status = AE_OK;
451 	union acpi_generic_state *state_list = NULL;
452 	union acpi_operand_object *next_object = NULL;
453 	union acpi_generic_state *state;
454 	u32 i;
455 
456 	ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
457 
458 	while (object) {
459 
460 		/* Make sure that this isn't a namespace handle */
461 
462 		if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
463 			ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
464 					  "Object %p is NS handle\n", object));
465 			return_ACPI_STATUS(AE_OK);
466 		}
467 
468 		/*
469 		 * All sub-objects must have their reference count incremented also.
470 		 * Different object types have different subobjects.
471 		 */
472 		switch (object->common.type) {
473 		case ACPI_TYPE_DEVICE:
474 		case ACPI_TYPE_PROCESSOR:
475 		case ACPI_TYPE_POWER:
476 		case ACPI_TYPE_THERMAL:
477 
478 			/* Update the notify objects for these types (if present) */
479 
480 			acpi_ut_update_ref_count(object->common_notify.
481 						 system_notify, action);
482 			acpi_ut_update_ref_count(object->common_notify.
483 						 device_notify, action);
484 			break;
485 
486 		case ACPI_TYPE_PACKAGE:
487 			/*
488 			 * We must update all the sub-objects of the package,
489 			 * each of whom may have their own sub-objects.
490 			 */
491 			for (i = 0; i < object->package.count; i++) {
492 				/*
493 				 * Push each element onto the stack for later processing.
494 				 * Note: There can be null elements within the package,
495 				 * these are simply ignored
496 				 */
497 				status =
498 				    acpi_ut_create_update_state_and_push
499 				    (object->package.elements[i], action,
500 				     &state_list);
501 				if (ACPI_FAILURE(status)) {
502 					goto error_exit;
503 				}
504 			}
505 			break;
506 
507 		case ACPI_TYPE_BUFFER_FIELD:
508 
509 			next_object = object->buffer_field.buffer_obj;
510 			break;
511 
512 		case ACPI_TYPE_LOCAL_REGION_FIELD:
513 
514 			next_object = object->field.region_obj;
515 			break;
516 
517 		case ACPI_TYPE_LOCAL_BANK_FIELD:
518 
519 			next_object = object->bank_field.bank_obj;
520 			status =
521 			    acpi_ut_create_update_state_and_push(object->
522 								 bank_field.
523 								 region_obj,
524 								 action,
525 								 &state_list);
526 			if (ACPI_FAILURE(status)) {
527 				goto error_exit;
528 			}
529 			break;
530 
531 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
532 
533 			next_object = object->index_field.index_obj;
534 			status =
535 			    acpi_ut_create_update_state_and_push(object->
536 								 index_field.
537 								 data_obj,
538 								 action,
539 								 &state_list);
540 			if (ACPI_FAILURE(status)) {
541 				goto error_exit;
542 			}
543 			break;
544 
545 		case ACPI_TYPE_LOCAL_REFERENCE:
546 			/*
547 			 * The target of an Index (a package, string, or buffer) or a named
548 			 * reference must track changes to the ref count of the index or
549 			 * target object.
550 			 */
551 			if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
552 			    (object->reference.class == ACPI_REFCLASS_NAME)) {
553 				next_object = object->reference.object;
554 			}
555 			break;
556 
557 		case ACPI_TYPE_REGION:
558 		default:
559 			break;	/* No subobjects for all other types */
560 		}
561 
562 		/*
563 		 * Now we can update the count in the main object. This can only
564 		 * happen after we update the sub-objects in case this causes the
565 		 * main object to be deleted.
566 		 */
567 		acpi_ut_update_ref_count(object, action);
568 		object = NULL;
569 
570 		/* Move on to the next object to be updated */
571 
572 		if (next_object) {
573 			object = next_object;
574 			next_object = NULL;
575 		} else if (state_list) {
576 			state = acpi_ut_pop_generic_state(&state_list);
577 			object = state->update.object;
578 			acpi_ut_delete_generic_state(state);
579 		}
580 	}
581 
582 	return_ACPI_STATUS(AE_OK);
583 
584       error_exit:
585 
586 	ACPI_EXCEPTION((AE_INFO, status,
587 			"Could not update object reference count"));
588 
589 	/* Free any stacked Update State objects */
590 
591 	while (state_list) {
592 		state = acpi_ut_pop_generic_state(&state_list);
593 		acpi_ut_delete_generic_state(state);
594 	}
595 
596 	return_ACPI_STATUS(status);
597 }
598 
599 /*******************************************************************************
600  *
601  * FUNCTION:    acpi_ut_add_reference
602  *
603  * PARAMETERS:  Object          - Object whose reference count is to be
604  *                                incremented
605  *
606  * RETURN:      None
607  *
608  * DESCRIPTION: Add one reference to an ACPI object
609  *
610  ******************************************************************************/
611 
612 void acpi_ut_add_reference(union acpi_operand_object *object)
613 {
614 
615 	ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
616 
617 	/* Ensure that we have a valid object */
618 
619 	if (!acpi_ut_valid_internal_object(object)) {
620 		return_VOID;
621 	}
622 
623 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
624 			  "Obj %p Current Refs=%X [To Be Incremented]\n",
625 			  object, object->common.reference_count));
626 
627 	/* Increment the reference count */
628 
629 	(void)acpi_ut_update_object_reference(object, REF_INCREMENT);
630 	return_VOID;
631 }
632 
633 /*******************************************************************************
634  *
635  * FUNCTION:    acpi_ut_remove_reference
636  *
637  * PARAMETERS:  Object         - Object whose ref count will be decremented
638  *
639  * RETURN:      None
640  *
641  * DESCRIPTION: Decrement the reference count of an ACPI internal object
642  *
643  ******************************************************************************/
644 
645 void acpi_ut_remove_reference(union acpi_operand_object *object)
646 {
647 
648 	ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
649 
650 	/*
651 	 * Allow a NULL pointer to be passed in, just ignore it. This saves
652 	 * each caller from having to check. Also, ignore NS nodes.
653 	 *
654 	 */
655 	if (!object ||
656 	    (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
657 		return_VOID;
658 	}
659 
660 	/* Ensure that we have a valid object */
661 
662 	if (!acpi_ut_valid_internal_object(object)) {
663 		return_VOID;
664 	}
665 
666 	ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
667 			  "Obj %p Current Refs=%X [To Be Decremented]\n",
668 			  object, object->common.reference_count));
669 
670 	/*
671 	 * Decrement the reference count, and only actually delete the object
672 	 * if the reference count becomes 0. (Must also decrement the ref count
673 	 * of all subobjects!)
674 	 */
675 	(void)acpi_ut_update_object_reference(object, REF_DECREMENT);
676 	return_VOID;
677 }
678