drivers/acpi/utilities/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 <acpi/acinterp.h>
  46 #include <acpi/acnamesp.h>
  47 #include <acpi/acevents.h>
  48
  49 #define _COMPONENT          ACPI_UTILITIES
  50 ACPI_MODULE_NAME("utdelete")
  51
  52 /* Local prototypes */
  53 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object);
  54
  55 static void
  56 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action);
  57
  58 /*******************************************************************************
  59  *
  60  * FUNCTION:    acpi_ut_delete_internal_obj
  61  *
  62  * PARAMETERS:  Object         - Object to be deleted
  63  *
  64  * RETURN:      None
  65  *
  66  * DESCRIPTION: Low level object deletion, after reference counts have been
  67  *              updated (All reference counts, including sub-objects!)
  68  *
  69  ******************************************************************************/
  70
  71 static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
  72 {
  73         void *obj_pointer = NULL;
  74         union acpi_operand_object *handler_desc;
  75         union acpi_operand_object *second_desc;
  76         union acpi_operand_object *next_desc;
  77
  78         ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
  79
  80         if (!object) {
  81                 return_VOID;
  82         }
  83
  84         /*
  85          * Must delete or free any pointers within the object that are not
  86          * actual ACPI objects (for example, a raw buffer pointer).
  87          */
  88         switch (ACPI_GET_OBJECT_TYPE(object)) {
  89         case ACPI_TYPE_STRING:
  90
  91                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
  92                                   "**** String %p, ptr %p\n", object,
  93                                   object->string.pointer));
  94
  95                 /* Free the actual string buffer */
  96
  97                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
  98
  99                         /* But only if it is NOT a pointer into an ACPI table */
 100
 101                         obj_pointer = object->string.pointer;
 102                 }
 103                 break;
 104
 105         case ACPI_TYPE_BUFFER:
 106
 107                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 108                                   "**** Buffer %p, ptr %p\n", object,
 109                                   object->buffer.pointer));
 110
 111                 /* Free the actual buffer */
 112
 113                 if (!(object->common.flags & AOPOBJ_STATIC_POINTER)) {
 114
 115                         /* But only if it is NOT a pointer into an ACPI table */
 116
 117                         obj_pointer = object->buffer.pointer;
 118                 }
 119                 break;
 120
 121         case ACPI_TYPE_PACKAGE:
 122
 123                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 124                                   " **** Package of count %X\n",
 125                                   object->package.count));
 126
 127                 /*
 128                  * Elements of the package are not handled here, they are deleted
 129                  * separately
 130                  */
 131
 132                 /* Free the (variable length) element pointer array */
 133
 134                 obj_pointer = object->package.elements;
 135                 break;
 136
 137                 /*
 138                  * These objects have a possible list of notify handlers.
 139                  * Device object also may have a GPE block.
 140                  */
 141         case ACPI_TYPE_DEVICE:
 142
 143                 if (object->device.gpe_block) {
 144                         (void)acpi_ev_delete_gpe_block(object->device.
 145                                                        gpe_block);
 146                 }
 147
 148                 /*lint -fallthrough */
 149
 150         case ACPI_TYPE_PROCESSOR:
 151         case ACPI_TYPE_THERMAL:
 152
 153                 /* Walk the notify handler list for this object */
 154
 155                 handler_desc = object->common_notify.handler;
 156                 while (handler_desc) {
 157                         next_desc = handler_desc->address_space.next;
 158                         acpi_ut_remove_reference(handler_desc);
 159                         handler_desc = next_desc;
 160                 }
 161                 break;
 162
 163         case ACPI_TYPE_MUTEX:
 164
 165                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 166                                   "***** Mutex %p, OS Mutex %p\n",
 167                                   object, object->mutex.os_mutex));
 168
 169                 if (object == acpi_gbl_global_lock_mutex) {
 170
 171                         /* Global Lock has extra semaphore */
 172
 173                         (void)
 174                             acpi_os_delete_semaphore
 175                             (acpi_gbl_global_lock_semaphore);
 176                         acpi_gbl_global_lock_semaphore = NULL;
 177
 178                         acpi_os_delete_mutex(object->mutex.os_mutex);
 179                         acpi_gbl_global_lock_mutex = NULL;
 180                 } else {
 181                         acpi_ex_unlink_mutex(object);
 182                         acpi_os_delete_mutex(object->mutex.os_mutex);
 183                 }
 184                 break;
 185
 186         case ACPI_TYPE_EVENT:
 187
 188                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 189                                   "***** Event %p, OS Semaphore %p\n",
 190                                   object, object->event.os_semaphore));
 191
 192                 (void)acpi_os_delete_semaphore(object->event.os_semaphore);
 193                 object->event.os_semaphore = NULL;
 194                 break;
 195
 196         case ACPI_TYPE_METHOD:
 197
 198                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 199                                   "***** Method %p\n", object));
 200
 201                 /* Delete the method mutex if it exists */
 202
 203                 if (object->method.mutex) {
 204                         acpi_os_delete_mutex(object->method.mutex->mutex.
 205                                              os_mutex);
 206                         acpi_ut_delete_object_desc(object->method.mutex);
 207                         object->method.mutex = NULL;
 208                 }
 209                 break;
 210
 211         case ACPI_TYPE_REGION:
 212
 213                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 214                                   "***** Region %p\n", object));
 215
 216                 second_desc = acpi_ns_get_secondary_object(object);
 217                 if (second_desc) {
 218                         /*
 219                          * Free the region_context if and only if the handler is one of the
 220                          * default handlers -- and therefore, we created the context object
 221                          * locally, it was not created by an external caller.
 222                          */
 223                         handler_desc = object->region.handler;
 224                         if (handler_desc) {
 225                                 if (handler_desc->address_space.handler_flags &
 226                                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {
 227
 228                                         /* Deactivate region and free region context */
 229
 230                                         if (handler_desc->address_space.setup) {
 231                                                 (void)handler_desc->
 232                                                     address_space.setup(object,
 233                                                                         ACPI_REGION_DEACTIVATE,
 234                                                                         handler_desc->
 235                                                                         address_space.
 236                                                                         context,
 237                                                                         &second_desc->
 238                                                                         extra.
 239                                                                         region_context);
 240                                         }
 241                                 }
 242
 243                                 acpi_ut_remove_reference(handler_desc);
 244                         }
 245
 246                         /* Now we can free the Extra object */
 247
 248                         acpi_ut_delete_object_desc(second_desc);
 249                 }
 250                 break;
 251
 252         case ACPI_TYPE_BUFFER_FIELD:
 253
 254                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 255                                   "***** Buffer Field %p\n", object));
 256
 257                 second_desc = acpi_ns_get_secondary_object(object);
 258                 if (second_desc) {
 259                         acpi_ut_delete_object_desc(second_desc);
 260                 }
 261                 break;
 262
 263         case ACPI_TYPE_LOCAL_BANK_FIELD:
 264
 265                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 266                                   "***** Bank Field %p\n", object));
 267
 268                 second_desc = acpi_ns_get_secondary_object(object);
 269                 if (second_desc) {
 270                         acpi_ut_delete_object_desc(second_desc);
 271                 }
 272                 break;
 273
 274         default:
 275                 break;
 276         }
 277
 278         /* Free any allocated memory (pointer within the object) found above */
 279
 280         if (obj_pointer) {
 281                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 282                                   "Deleting Object Subptr %p\n", obj_pointer));
 283                 ACPI_FREE(obj_pointer);
 284         }
 285
 286         /* Now the object can be safely deleted */
 287
 288         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Deleting Object %p [%s]\n",
 289                           object, acpi_ut_get_object_type_name(object)));
 290
 291         acpi_ut_delete_object_desc(object);
 292         return_VOID;
 293 }
 294
 295 /*******************************************************************************
 296  *
 297  * FUNCTION:    acpi_ut_delete_internal_object_list
 298  *
 299  * PARAMETERS:  obj_list        - Pointer to the list to be deleted
 300  *
 301  * RETURN:      None
 302  *
 303  * DESCRIPTION: This function deletes an internal object list, including both
 304  *              simple objects and package objects
 305  *
 306  ******************************************************************************/
 307
 308 void acpi_ut_delete_internal_object_list(union acpi_operand_object **obj_list)
 309 {
 310         union acpi_operand_object **internal_obj;
 311
 312         ACPI_FUNCTION_TRACE(ut_delete_internal_object_list);
 313
 314         /* Walk the null-terminated internal list */
 315
 316         for (internal_obj = obj_list; *internal_obj; internal_obj++) {
 317                 acpi_ut_remove_reference(*internal_obj);
 318         }
 319
 320         /* Free the combined parameter pointer list and object array */
 321
 322         ACPI_FREE(obj_list);
 323         return_VOID;
 324 }
 325
 326 /*******************************************************************************
 327  *
 328  * FUNCTION:    acpi_ut_update_ref_count
 329  *
 330  * PARAMETERS:  Object          - Object whose ref count is to be updated
 331  *              Action          - What to do
 332  *
 333  * RETURN:      New ref count
 334  *
 335  * DESCRIPTION: Modify the ref count and return it.
 336  *
 337  ******************************************************************************/
 338
 339 static void
 340 acpi_ut_update_ref_count(union acpi_operand_object *object, u32 action)
 341 {
 342         u16 count;
 343         u16 new_count;
 344
 345         ACPI_FUNCTION_NAME(ut_update_ref_count);
 346
 347         if (!object) {
 348                 return;
 349         }
 350
 351         count = object->common.reference_count;
 352         new_count = count;
 353
 354         /*
 355          * Perform the reference count action (increment, decrement, force delete)
 356          */
 357         switch (action) {
 358         case REF_INCREMENT:
 359
 360                 new_count++;
 361                 object->common.reference_count = new_count;
 362
 363                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 364                                   "Obj %p Refs=%X, [Incremented]\n",
 365                                   object, new_count));
 366                 break;
 367
 368         case REF_DECREMENT:
 369
 370                 if (count < 1) {
 371                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 372                                           "Obj %p Refs=%X, can't decrement! (Set to 0)\n",
 373                                           object, new_count));
 374
 375                         new_count = 0;
 376                 } else {
 377                         new_count--;
 378
 379                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 380                                           "Obj %p Refs=%X, [Decremented]\n",
 381                                           object, new_count));
 382                 }
 383
 384                 if (ACPI_GET_OBJECT_TYPE(object) == ACPI_TYPE_METHOD) {
 385                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 386                                           "Method Obj %p Refs=%X, [Decremented]\n",
 387                                           object, new_count));
 388                 }
 389
 390                 object->common.reference_count = new_count;
 391                 if (new_count == 0) {
 392                         acpi_ut_delete_internal_obj(object);
 393                 }
 394                 break;
 395
 396         case REF_FORCE_DELETE:
 397
 398                 ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 399                                   "Obj %p Refs=%X, Force delete! (Set to 0)\n",
 400                                   object, count));
 401
 402                 new_count = 0;
 403                 object->common.reference_count = new_count;
 404                 acpi_ut_delete_internal_obj(object);
 405                 break;
 406
 407         default:
 408
 409                 ACPI_ERROR((AE_INFO, "Unknown action (%X)", action));
 410                 break;
 411         }
 412
 413         /*
 414          * Sanity check the reference count, for debug purposes only.
 415          * (A deleted object will have a huge reference count)
 416          */
 417         if (count > ACPI_MAX_REFERENCE_COUNT) {
 418                 ACPI_WARNING((AE_INFO,
 419                               "Large Reference Count (%X) in object %p", count,
 420                               object));
 421         }
 422 }
 423
 424 /*******************************************************************************
 425  *
 426  * FUNCTION:    acpi_ut_update_object_reference
 427  *
 428  * PARAMETERS:  Object              - Increment ref count for this object
 429  *                                    and all sub-objects
 430  *              Action              - Either REF_INCREMENT or REF_DECREMENT or
 431  *                                    REF_FORCE_DELETE
 432  *
 433  * RETURN:      Status
 434  *
 435  * DESCRIPTION: Increment the object reference count
 436  *
 437  * Object references are incremented when:
 438  * 1) An object is attached to a Node (namespace object)
 439  * 2) An object is copied (all subobjects must be incremented)
 440  *
 441  * Object references are decremented when:
 442  * 1) An object is detached from an Node
 443  *
 444  ******************************************************************************/
 445
 446 acpi_status
 447 acpi_ut_update_object_reference(union acpi_operand_object *object, u16 action)
 448 {
 449         acpi_status status = AE_OK;
 450         union acpi_generic_state *state_list = NULL;
 451         union acpi_operand_object *next_object = NULL;
 452         union acpi_generic_state *state;
 453         u32 i;
 454
 455         ACPI_FUNCTION_TRACE_PTR(ut_update_object_reference, object);
 456
 457         while (object) {
 458
 459                 /* Make sure that this isn't a namespace handle */
 460
 461                 if (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED) {
 462                         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 463                                           "Object %p is NS handle\n", object));
 464                         return_ACPI_STATUS(AE_OK);
 465                 }
 466
 467                 /*
 468                  * All sub-objects must have their reference count incremented also.
 469                  * Different object types have different subobjects.
 470                  */
 471                 switch (ACPI_GET_OBJECT_TYPE(object)) {
 472                 case ACPI_TYPE_DEVICE:
 473                 case ACPI_TYPE_PROCESSOR:
 474                 case ACPI_TYPE_POWER:
 475                 case ACPI_TYPE_THERMAL:
 476
 477                         /* Update the notify objects for these types (if present) */
 478
 479                         acpi_ut_update_ref_count(object->common_notify.
 480                                                  system_notify, action);
 481                         acpi_ut_update_ref_count(object->common_notify.
 482                                                  device_notify, action);
 483                         break;
 484
 485                 case ACPI_TYPE_PACKAGE:
 486                         /*
 487                          * We must update all the sub-objects of the package,
 488                          * each of whom may have their own sub-objects.
 489                          */
 490                         for (i = 0; i < object->package.count; i++) {
 491                                 /*
 492                                  * Push each element onto the stack for later processing.
 493                                  * Note: There can be null elements within the package,
 494                                  * these are simply ignored
 495                                  */
 496                                 status =
 497                                     acpi_ut_create_update_state_and_push
 498                                     (object->package.elements[i], action,
 499                                      &state_list);
 500                                 if (ACPI_FAILURE(status)) {
 501                                         goto error_exit;
 502                                 }
 503                         }
 504                         break;
 505
 506                 case ACPI_TYPE_BUFFER_FIELD:
 507
 508                         next_object = object->buffer_field.buffer_obj;
 509                         break;
 510
 511                 case ACPI_TYPE_LOCAL_REGION_FIELD:
 512
 513                         next_object = object->field.region_obj;
 514                         break;
 515
 516                 case ACPI_TYPE_LOCAL_BANK_FIELD:
 517
 518                         next_object = object->bank_field.bank_obj;
 519                         status =
 520                             acpi_ut_create_update_state_and_push(object->
 521                                                                  bank_field.
 522                                                                  region_obj,
 523                                                                  action,
 524                                                                  &state_list);
 525                         if (ACPI_FAILURE(status)) {
 526                                 goto error_exit;
 527                         }
 528                         break;
 529
 530                 case ACPI_TYPE_LOCAL_INDEX_FIELD:
 531
 532                         next_object = object->index_field.index_obj;
 533                         status =
 534                             acpi_ut_create_update_state_and_push(object->
 535                                                                  index_field.
 536                                                                  data_obj,
 537                                                                  action,
 538                                                                  &state_list);
 539                         if (ACPI_FAILURE(status)) {
 540                                 goto error_exit;
 541                         }
 542                         break;
 543
 544                 case ACPI_TYPE_LOCAL_REFERENCE:
 545                         /*
 546                          * The target of an Index (a package, string, or buffer) or a named
 547                          * reference must track changes to the ref count of the index or
 548                          * target object.
 549                          */
 550                         if ((object->reference.class == ACPI_REFCLASS_INDEX) ||
 551                             (object->reference.class == ACPI_REFCLASS_NAME)) {
 552                                 next_object = object->reference.object;
 553                         }
 554                         break;
 555
 556                 case ACPI_TYPE_REGION:
 557                 default:
 558                         break;  /* No subobjects for all other types */
 559                 }
 560
 561                 /*
 562                  * Now we can update the count in the main object. This can only
 563                  * happen after we update the sub-objects in case this causes the
 564                  * main object to be deleted.
 565                  */
 566                 acpi_ut_update_ref_count(object, action);
 567                 object = NULL;
 568
 569                 /* Move on to the next object to be updated */
 570
 571                 if (next_object) {
 572                         object = next_object;
 573                         next_object = NULL;
 574                 } else if (state_list) {
 575                         state = acpi_ut_pop_generic_state(&state_list);
 576                         object = state->update.object;
 577                         acpi_ut_delete_generic_state(state);
 578                 }
 579         }
 580
 581         return_ACPI_STATUS(AE_OK);
 582
 583       error_exit:
 584
 585         ACPI_EXCEPTION((AE_INFO, status,
 586                         "Could not update object reference count"));
 587
 588         /* Free any stacked Update State objects */
 589
 590         while (state_list) {
 591                 state = acpi_ut_pop_generic_state(&state_list);
 592                 acpi_ut_delete_generic_state(state);
 593         }
 594
 595         return_ACPI_STATUS(status);
 596 }
 597
 598 /*******************************************************************************
 599  *
 600  * FUNCTION:    acpi_ut_add_reference
 601  *
 602  * PARAMETERS:  Object          - Object whose reference count is to be
 603  *                                incremented
 604  *
 605  * RETURN:      None
 606  *
 607  * DESCRIPTION: Add one reference to an ACPI object
 608  *
 609  ******************************************************************************/
 610
 611 void acpi_ut_add_reference(union acpi_operand_object *object)
 612 {
 613
 614         ACPI_FUNCTION_TRACE_PTR(ut_add_reference, object);
 615
 616         /* Ensure that we have a valid object */
 617
 618         if (!acpi_ut_valid_internal_object(object)) {
 619                 return_VOID;
 620         }
 621
 622         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 623                           "Obj %p Current Refs=%X [To Be Incremented]\n",
 624                           object, object->common.reference_count));
 625
 626         /* Increment the reference count */
 627
 628         (void)acpi_ut_update_object_reference(object, REF_INCREMENT);
 629         return_VOID;
 630 }
 631
 632 /*******************************************************************************
 633  *
 634  * FUNCTION:    acpi_ut_remove_reference
 635  *
 636  * PARAMETERS:  Object         - Object whose ref count will be decremented
 637  *
 638  * RETURN:      None
 639  *
 640  * DESCRIPTION: Decrement the reference count of an ACPI internal object
 641  *
 642  ******************************************************************************/
 643
 644 void acpi_ut_remove_reference(union acpi_operand_object *object)
 645 {
 646
 647         ACPI_FUNCTION_TRACE_PTR(ut_remove_reference, object);
 648
 649         /*
 650          * Allow a NULL pointer to be passed in, just ignore it. This saves
 651          * each caller from having to check. Also, ignore NS nodes.
 652          *
 653          */
 654         if (!object ||
 655             (ACPI_GET_DESCRIPTOR_TYPE(object) == ACPI_DESC_TYPE_NAMED)) {
 656                 return_VOID;
 657         }
 658
 659         /* Ensure that we have a valid object */
 660
 661         if (!acpi_ut_valid_internal_object(object)) {
 662                 return_VOID;
 663         }
 664
 665         ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
 666                           "Obj %p Current Refs=%X [To Be Decremented]\n",
 667                           object, object->common.reference_count));
 668
 669         /*
 670          * Decrement the reference count, and only actually delete the object
 671          * if the reference count becomes 0. (Must also decrement the ref count
 672          * of all subobjects!)
 673          */
 674         (void)acpi_ut_update_object_reference(object, REF_DECREMENT);
 675         return_VOID;
 676 }