ACPICA: hide private headers
[linux-2.6.git] / drivers / acpi / acpica / utdelete.c
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 (ACPI_GET_OBJECT_TYPE(object)) {
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 (ACPI_GET_OBJECT_TYPE(object) == 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 (ACPI_GET_OBJECT_TYPE(object)) {
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 }