Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
[pandora-kernel.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 - 2010, 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                 /* 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
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
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
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
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
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 }