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         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 }